A genome-wide association study identifies susceptibility loci for Wilms tumor

Wilms Tumor

Objective: Genome-wide association studies (GWAS) have identified more than 50 loci for lung cancer risk. However, susceptibility genes and the underlying mechanisms for these risk loci remain largely unknown. We conducted a transcriptome-wide association study (TWAS) to identify susceptibility genes for lung cancer. Methods: Transcriptome data from normal lung tissue and whole-genome sequencing data from 444 participants of European ancestry in the Genotype-Tissue Expression (GTEx, version 8) were used to build lung-tissue models to predict gene expression levels. Lung-tissue prediction models were successfully established for 10,802 genes with a model performance r > 0.1 and P < 0.05. We also built joint-tissue models using the joint-tissue imputation (JTI) framework, which leverages transcriptome data from lung tissue and 48 other tissue types from the 444 participants in GTEx. Joint-tissue models were successfully established for 12,629 genes with a model performance r > 0.1 and P < 0.05. These prediction models were applied to the GWAS data comprised of 29,266 lung cancer cases and 56,450 controls of European ancestry, in order to evaluate genetically predicted gene expression levels in association with lung cancer risk. Results: We found 44 genes whose genetically predicted expression levels were significantly associated with overall lung cancer risk at the Bonferroni correction significance threshold. Among the 44 genes, four were located at least 500kb away from any of the leading variants identified previously in GWAS. Of these four genes, only the CCHCR1 gene has been reported in previous TWAS, and the other three genes, LY6G5B, PRSS16, and C19orf54, have never been reported in previous GWAS or TWAS. For each of these three novel genes, consistent associations were observed in both lung-tissue and joint-tissue models. For the 40 genes located in previously identified GWAS loci, after adjusting for GWAS-identified variants, the associations for the majority of them became non-significant. However, the associations did not change materially for UCKL1 or PRPF6. These results suggest that the associations for these two genes were independent from previous GWSA-identified signals. We also identified 10 genes located at least 500kb away from GWAS-identified loci that were associated with lung cancer histological subtypes, e.g., adenocarcinoma (DCBLD1 and AQP3), squamous cell carcinoma (ZSCAN26, BLOC1S2, ABCF1, and ZSCAN9), and small cell lung cancer (BTN2A2, TMA16, RP11-218F10.3, and FRS3). An additional 7 genes located in GWAS loci were associated with risk of lung cancer histological subtypes but not with overall lung cancer risk, including 4 genes for adenocarcinoma (TP63, STN1, FAM227B, and TPRG1) and 3 genes for squamous cell carcinoma (DDAH2, OR2H2, and NELFE). Conclusion: Our TWAS identified lung cancer susceptibility genes, providing new insight into the genetics of lung cancer etiology. Citation Format: Tianying Zhao, Jiajun Shi, Yaohua Yang, Jie Ping, Xiao Ou Shu, Wei Zheng, Jirong Long, Qiuyin Cai. Transcriptome-wide association study identifies susceptibility loci and genes for lung cancer risk [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB045.

Germline pathogenic variants in AMER1 cause osteopathia striata with cranial sclerosis (OSCS: OMIM 300373), an X-linked sclerosing bone disorder. Female heterozygotes exhibit metaphyseal striations in long bones, macrocephaly, cleft palate, and, occasionally, learning disability. Male hemizygotes typically manifest the condition as fetal or neonatal death. Somatically acquired variants in AMER1 are found in neoplastic tissue in 15-30% of patients with Wilms tumor; however, to date, only one individual with OSCS has been reported with a Wilms tumor. Here we present four cases of Wilms tumor in unrelated individuals with OSCS, including the single previously published case. We also report the first case of bilateral Wilms tumor in a patient with OSCS. Tumor tissue analysis showed no clear pattern of histological subtypes. In Beckwith-Wiedemann syndrome, which has a known predisposition to Wilms tumor development, clinical protocols have been developed for tumor surveillance. In the absence of further evidence, we propose a similar protocol for patients with OSCS to be instituted as an initial precautionary approach to tumor surveillance. Further evidence is needed to refine this protocol and to evaluate the possibility of development of other neoplasms later in life, in patients with OSCS.

Wilms tumor is the most common pediatric renal malignancy, but the parameters that are important to its invasion capacity are poorly understood. The aim of this study was to identify new proteins associated with the invasion capacity of Wilms tumor. Gene expression profiles for 15 primary Wilms tumor samples were determined by Affymetrix Genechip® Human Genome Ul33A microarray analysis. The gene expression profiles for selected genes was further confirmed by quantitative RT-PCR analysis. Immunohistochemical analysis was performed on 25 Wilms tumor cases to confirm expression for Bcl2A1, EphB2, MSX1, and RIN1. Using microarray analysis 14 genes showed differential expression (P < 0.05) comparing stage 1 non-invasive Wilms tumor to stages 2-4 invasive Wilms tumor. The differential expression for Bcl2A1, EphB2, MSX1, and RIN1 was confirmed by quantitative RT-PCR. MSX1 protein was statistically significantly lower in stages 2-4 invasive Wilms tumor cases compared to stage 1 non-invasive cases (P = 0.013). EphB2 protein was higher in stages 2-4 Wilms tumor cases compared to stage 1 cases (P = 0.006). There was no statistically significant difference between stages 1 and 2-4 Wilms tumor for Bcl2A1 (P = 0.230) or RIN1 (P = 0.969) at the protein level. Our results indicate that MSX1 may be associated with the invasion capacity of Wilms tumors. RIN1 is a downstream effector of RAS and Bcl2A1 functions as an anti-apoptotic protein. EphB2 is an ephrin receptor and is up-regulated in invasive tumors but its role needs to be confirmed in further cases of Wilms tumors.

Children with hemihypertrophy are screened for Wilms tumor, because this condition is a risk factor for developing the neoplasm. Patients with Klippel-Trenaunay syndrome (KTS) are often considered potential candidates for Wilms tumor, because they have unilateral overgrowth of the lower limb. In our experience, however, an association between KTS and Wilms tumor has not been observed. To determine whether KTS and Wilms tumor are associated, we reviewed our institutional experience for patients with both diagnoses and searched the Klippel-Trenaunay literature for patients with Wilms tumor. The National Wilms Tumor Study Group database also was studied to identify patients with KTS. Two-sided exact binomial tests were used to evaluate whether patients with 1 condition had an increased risk for the other. Ninety-five percent confidence intervals for these 2 risks were compared with the general population risks of Wilms tumor (1 in 10 000) and KTS (1 in 47 313). None of the 115 patients with KTS followed at our institution developed Wilms tumor. One case of Wilms tumor has been reported in 1363 patients with KTS in the literature, giving a confidence interval of (1/57 377) and (1/267). None of the 8614 patients in the National Wilms Tumor Study Group database had KTS, giving a confidence interval of (0, 1/2336). Because the risks of KTS and Wilms tumor in the population fall within these confidence intervals, one cannot conclude that the risks of KTS among Wilms tumor patients or Wilms tumor among KTS patients are any different from the corresponding risks in the general population. Patients with KTS are not at increased risk for developing Wilms tumor and thus should not undergo routine ultrasonographic screening.

Hypovolemic shock (Dengue shock syndrome (DSS)), is the commonest life-threatening complication of dengue. We conducted a genome-wide association study of 2,008 pediatric cases treated for DSS and 2,018 controls from Vietnam. Replication of the most significantly associated markers was carried out in an independent Vietnamese follow-up sample of 1,737 cases and 2,934 controls. Polymorphisms within two genes showed genome-wide significant association with DSS (Pmeta = 4.41 × 10−11, per-allele odds ratio (OR) = 1.34 for MICB rs3132468 located within the broad MHC region and Pmeta = 3.08 × 10−10, per-allele OR = 0.80 for PLCE1 rs3765524). Our data implicates MICB is an important determinant in early immune control of dengue virus infection and PLCE1 a factor in vascular endothelial dysfunction and circulatory hypovolemia.

Purpose. Clear cell sarcoma of the kidney (CCSK) is an uncommon malignant renal tumor. It is the second most common renal pediatric renal malignancy after Wilms tumor. It exhibits a heterogeneous morphology, with overlapping features with its close differentials, which results in diagnostic challenges. There was no specific immunohistochemical marker in the past, to help in this regard. BCOR antibody has recently been suggested to be helpful in the differential diagnosis. We aim to study the utility of the BCOR antibody in the diagnosis of CCSK. Methods. We selected a total of 27 cases of CCSK (n = 12), Wilms tumor (n = 12), and congenital mesoblastic nephroma (n = 3). All cases were evaluated for the extent and intensity of nuclear labeling for BCOR antibody by immunohistochemistry (IHC). Results. We found that BCOR IHC was positive in 11 out of 12 cases with diffuse and strong staining in 8 of the cases. None of the cases of Wilms tumor and congenital mesoblastic nephroma were positive. Only 2 cases of Wilms tumor showed minimal and weak staining in <5% of cells. Conclusion. Diffuse and strong nuclear staining for the BCOR antibody is highly specific for CCSK among common pediatric renal malignancies. Our study confirms that BCOR IHC is a good IHC marker for the diagnosis of CCSK.

We attempted to determine whether all cases of AWTA (anirida-Wilms tumor association) or any of the following groups of patients show 11p deletion: cases of Wilms tumor with congenital abnormalities other than aniridia, those without any congenital abnormalities, tumor itself in cases of Wilms tumor without constitutional 11p deletion and cases of aniridia or hemihypertrophy without Wilms tumor. We studied a total of 29 index patients including five cases of AWTA, four cases of Wilms tumor with various congenital abnormalities, 16 cases of Wilms tumor without other abnormalities, three cases of aniridia in one of which Wilms tumor developed later and a case of hemihypertrophy. In all five cases of AWTA and in a case of aniridia who later developed Wilms tumor, 11p deletion involving the p13 band was detected. The mother of the latter also showed an identical 11p deletion. The common segment of deletion was the middle part of the p13. Two possible hypotheses on the mechanism through which Wilms tumor might develop were evaluated, based on the distribution of break points. All other cases, including five with tumor culture, showed a normal karyotype.

Identification of KCNJ15 as a Susceptibility Gene in Asian Patients with Type 2 Diabetes Mellitus

A cervical rib (CR), also known as a supernumerary or extra rib, is an additional rib that forms above the first rib, resulting from the overgrowth of the transverse process of a cervical vertebra. Increasingly recognized as a potential marker of developmental disruptions and genetic instability, CRs are believed to arise from mutations in homeobox (Hox) genes that influence axial skeletal development. While often asymptomatic, CRs have been linked to thoracic outlet syndrome and a higher prevalence in individuals with certain childhood cancers. Studies have reported associations between CRs and malignancies such as neuroblastoma, brain tumors, leukemia, sarcomas, Wilms tumor, and germ cell tumors, suggesting possible shared embryological pathways or genetic predispositions. However, conflicting research findings highlight inconsistencies in these associations, underscoring the need for further investigation. This review aims to assess the association between CRs and childhood cancers by examining prevalence rates, exploring genetic and developmental links, evaluating inconsistencies in existing research, and identifying gaps for future study to clarify the clinical significance of CRs in cancer risk assessment. Introduction A Cervical rib (CR), also known as a "neck rib" or "supernumerary rib," is an extra rib that forms above the first rib, near the collarbone. It develops due to an overgrowth of the transverse process of a cervical spine vertebra. It is thought to result from mutations in homeobox (Hox) genes, which play a role in shaping the axial skeleton in humans and vertebrates. This rib can occur on either side and may be unattached (floating) or fused with the first rib. It can range from a fully formed bone to a delicate fibrous strand [1]. The CRs are present in about 2% of the general adult population. The prevalence is higher in women, who are about twice as likely to have CRs as men. Additionally, ethnic differences have been observed, with one study finding that CRs are more common in African Americans than in whites [2]. Typically, CR is discovered incidentally through radiographic imaging unless it causes symptoms [3]. In some cases, CR can contribute to thoracic outlet syndrome by narrowing the interscalene triangle, leading to pain, weakness, numbness, or cold sensitivity in the affected limb [1, 4, 5]. The first documented clinical signs of neurovascular compression associated with CRs were reported by Cooper in 1818 [6]. Studies have demonstrated a higher prevalence of CRs in individuals with childhood cancers. This association may stem from disruptions in embryonic development during critical stages of blastogenesis, which can simultaneously lead to cervical segmentation defects and increase cancer susceptibility [7, 8]. Moreover, CRs are often regarded as markers of adverse developmental events or genetic instability. Their higher prevalence in stillborn fetuses and individuals with chromosomal abnormalities further underscores their potential role as indicators of systemic vulnerabilities that may contribute to malignancy risk. These findings highlight the importance of understanding rib anomalies (RAs) as anatomical curiosities and potential markers for identifying individuals at increased risk for certain cancers [9]. This study aims to review the association between CRs and cancer, with all referenced articles assessed for eligibility [10]. Studies Linking Rib Anomalies to Childhood Cancers Despite growing awareness of a possible connection between RAs and malignancies, research on this topic remains limited. Only four studies have examined this association, each providing valuable insights into the potential link. The earliest study by Schumacher et al. (1995) investigated the relationship between RAs and childhood malignancies by reviewing chest X-rays of 1,000 children with cancer and 200 control patients with non-malignant conditions. They found a significantly higher prevalence of RAs, particularly CRs, in children with certain malignancies compared to controls. This suggested that these skeletal abnormalities might be linked to altered morphogenesis in tumor development [7]. A decade later, Merks et al. (2005) conducted a more extensive study analyzing chest radiographs of 906 children with cancer and 881 healthy Caucasian pediatric controls. Their findings confirmed previous reports, demonstrating a higher occurrence of specific RAs in children with certain malignancies. They emphasized the potential role of genetic predisposition in cancer development and suggested that skeletal anomalies could serve as markers for underlying genetic abnormalities [8]. Loder et al. (2007) expanded on these findings by focusing on rib number variations in 218 children with malignancies and 200 control children who had been admitted for polytrauma or suspected child abuse. Their study highlighted a significant difference in rib counts between children with cancer and healthy controls. They speculated that genes involved in vertebral and rib development might also play a role in cancer predisposition, suggesting the possibility of using skeletal anomalies as a screening tool for early cancer detection [11]. Finally, Zierhut et al. (2011) reinforced the association between RAs and childhood cancers through a hospital-based case-control study of 459 pediatric cancer patients and 1,135 controls who had undergone chest X-rays for non-cancer-related reasons. Their research confirmed that children with cancer were more likely to have RAs, particularly those diagnosed with specific malignancies. They underscored the need for further studies to determine the biological mechanisms linking RAs to cancer development [12]. Cancers Linked to Cervical Ribs Neuroblastoma Neuroblastoma is a highly aggressive tumor that develops from neural crest cells and is the most common cancer in infants under one year old worldwide [13]. It represents about 10% of all pediatric cancers and primarily affects children within their first five years of life [14]. A defining characteristic of neuroblastoma is its highly variable clinical behavior. In approximately 50% of affected infants, the tumor regresses spontaneously, whereas in others, it advances into an aggressive, metastatic disease that is often resistant to standard treatments like chemoradiotherapy, stem cell transplantation, and immunotherapy [15]. This unpredictability complicates treatment, especially for high-risk patients who experience chemo-resistant relapse, with survival rates remaining below 40% [14]. The initiation and progression of neuroblastoma are driven by genetic abnormalities that interfere with cell division, proliferation, and apoptosis [15]. Significant genetic factors include MYCN amplification, TP53 deletions, ALK mutations or amplifications, TERT rearrangements, ATRX deletions or mutations, and segmental chromosomal aberrations. However, whole-genome sequencing studies have identified only a limited number of recurrent somatic mutations, making the development of targeted therapies challenging. Consequently, a precise understanding of the biological complexity and diversity of neuroblastoma is crucial for improving diagnostic and treatment approaches [15]. Schumacher et al. (1992) identified a strong correlation between neuroblastoma and CRs, reporting that 33% of children with neuroblastoma had CRs, a markedly higher prevalence than in the general population. This notable disparity suggests a potential developmental or genetic connection between neuroblastoma and skeletal anomalies. Furthermore, neuroblastoma was the only malignancy in their study to exhibit a significantly increased incidence of rib bifurcation (4.5%), a rate nearly four times higher than expected, reinforcing the possibility of disrupted skeletal development linked to the disease [7]. In contrast, Merks et al. (2005) analyzed 61 neuroblastoma patients and found that 9.8% had CRs, compared to 6.1% in the control group. While this suggests a slightly increased prevalence, the difference was not statistically significant (p = 0.252). This discrepancy with Schumacher et al. (1992) may be due to differences in sample size, diagnostic criteria, or population characteristics [7, 8]. Loder et al. (2007) took a broader approach by grouping neuroblastoma with other neural malignancies. Their findings showed a higher incidence of RAs (35%) in children with neural tumors compared to those with other malignancies. However, they did not specifically find an association between neuroblastoma and CRs. Among the eight neuroblastoma patients in their study, RAs were present, but no cases of CRs were observed. Instead, the most common skeletal abnormality was a reduced rib count, with affected children having 22 or 23 ribs instead of the typical 24. This suggests that while RAs may be linked to neuroblastoma, the specific presence of CRs may not be a defining characteristic [11]. Similarly, Zierhut et al. (2011) analyzed 31 neuroblastoma cases and found that 6.4% had RAs. However, the study did not report how many of these cases involved CRs specifically. The statistical analysis yielded an odds ratio (OR) of 1.46 (95% CI: 0.34–6.30) for any rib anomaly in neuroblastoma patients, indicating a slightly higher occurrence of skeletal abnormalities but without statistical significance. The lack of a significant association between RAs and neuroblastoma may be due to the study’s small sample size, which could have limited its ability to detect a stronger relationship [12]. Overall, while Schumacher et al. (1992) identified a strong association between neuroblastoma and CRs, subsequent studies, including those by Merks et al. (2005), Loder et al. (2007), and Zierhut et al. (2011), reported weaker or non-significant links [7, 8, 11, 12]. The inconsistencies across studies highlight the need for further research with larger sample sizes and more detailed skeletal analyses to determine whether CRs represent a meaningful developmental marker for neuroblastoma or if their observed association is due to broader skeletal anomalies. Brain Tumors A brain tumor forms when cells grow irregularly and multiply uncontrollably. These tumors may arise from brain cells, the meninges (the membranes surrounding the brain), glands, or nerves. They can cause direct damage to brain cells and elevate pressure within the skull, resulting in harmful effects [16]. Due to their severity, brain tumors are classified into different grades. Grade 1 tumors are the least aggressive, typically associated with more prolonged survival. They grow slowly, resemble normal cells under a microscope, and can often be effectively treated with surgical removal. Examples include pilocytic astrocytoma, ganglioglioma, and gangliocytoma. Grade 2 tumors also grow slowly but appear abnormal under a microscope. Some may invade nearby tissues and tend to recur, occasionally progressing to a higher grade [16]. Grade 3 tumors are malignant and share similarities with grade 2 tumors but are more likely to recur as grade 4 tumors. Grade 4 tumors are the most aggressive, growing rapidly and appearing highly abnormal under a microscope. They invade surrounding brain tissue, form new blood vessels, and contain areas of dead cells at their core. Glioblastoma Multiforme is a well-known example of a grade 4 tumor [16]. Brain tumors develop due to a combination of genetic, environmental, and molecular factors. Genetic predisposition plays a key role, with inherited syndromes such as neurofibromatosis and Li-Fraumeni syndrome increasing the risk. Environmental exposures, particularly ionizing radiation, are well-established contributors, while occupational exposure to chemicals and electromagnetic fields remains inconclusive. Viral infections, immune dysfunction, and chronic inflammation may also influence tumor development [17, 18]. The study by Schumacher et al. (1992) found that 27.4% of children with brain tumors had CRs, compared to only 5.5% in the control group (p &lt; 0.001). This substantial difference suggests a potential developmental link between CRs and brain tumors, possibly due to shared embryological pathways affecting both skeletal and neural development. The high prevalence reported in this study indicates that CRs might serve as an anatomical marker for underlying genetic or developmental disruptions associated with brain tumor formation [7]. Merks et al. (2005) further supported this hypothesis by identifying a significant association between CR anomalies and astrocytomas. Their study reported that 18.2% of childhood cancer patients with astrocytomas had CRs, compared to 6.1% in the control group. This finding suggests that certain subtypes of brain tumors, particularly astrocytomas, may have a stronger developmental association with CR anomalies [8]. However, Loder et al. (2007) did not find a strong link between brain tumors and CRs. While RAs were more frequent in children with neural malignancies (35%), none of these anomalies were identified as CRs. Instead, children with neural malignancies were found to be 6.23 times more likely to have an abnormal rib count compared to the control group. This suggests that while skeletal anomalies may be associated with neural tumors in general, CRs specifically may not be a consistent marker [11]. Zierhut et al. (2011) also provided a more tempered perspective. Their study examined 34 pediatric cases of central nervous system tumors, including brain tumors, and found that 8.8% (n = 3) had some form of rib anomaly. However, they did not identify a statistically significant association between CRs and brain tumors. This finding further weakens the case for a direct link and suggests that broader skeletal anomalies may be involved rather than CRs specifically [12]. Overall, while Schumacher et al. (1992) and Merks et al. (2005) suggest a possible association between CRs and brain tumors, the findings from Loder et al. (2007) and Zierhut et al. (2011) cast doubt on the specificity of this relationship [7, 8, 11, 12]. The inconsistencies across studies highlight the need for further research to determine whether CRs are a true marker for brain tumor risk or if their association is due to broader developmental abnormalities affecting multiple organ systems. Leukemia Leukemia is a frequently occurring cancer in both children and adults. It results from disruptions in normal cell regulation that lead to the uncontrolled growth of hematopoietic stem cells in the bone marrow. It is more commonly found in males and individuals of white ethnicity, with its prevalence increasing with age. On average, about one in 70 people will develop leukemia during their lifetime. The four main types of leukemia, each with unique characteristics, are acute lymphoblastic leukemia (ALL), acute myelogenous leukemia (AML), chronic lymphocytic leukemia, and chronic myelogenous leukemia [19]. Leukemia occurs worldwide, with a higher prevalence and overall mortality in more developed countries. However, the mortality rate tends to be greater in developing nations [20]. The development of leukemia results from a complex interaction between genetic predisposition and environmental influences, with neither factor alone provides a complete explanation. While significant strides have been made in identifying risk factors and potential disease mechanisms, the exact causes of most leukemia cases remain uncertain. Known risk factors include genetic syndromes, chromosomal abnormalities, radiation exposure, specific chemicals, certain viral infections, and prior cancer treatments, but these account for only a fraction of cases [20, 21]. The study by Schumacher et al. (1992) found a significant association between CRs and leukemia, with 26.8% (n = 227) of leukemia patients exhibiting CRs compared to only 5.5% (n = 11) in the control group (p &lt; 0.001). This finding suggests a potential developmental or genetic link between skeletal anomalies and leukemia, possibly due to disruptions in early embryonic development affecting both hematopoietic and skeletal systems [7]. Similarly, Merks et al. (2005) identified a significant association between CR anomalies and ALL, with a prevalence of 12.1% in ALL patients compared to 6.1% in controls (p = 0.011). This reinforces the idea that skeletal anomalies may serve as a marker for certain pediatric malignancies, though the underlying mechanisms remain unclear [8]. Loder et al. (2007) further examined RAs in leukemia patients. Among 218 children with malignancies, 75 had leukemia (64 with ALL and 11 with AML) [11]. The incidence of abnormal rib counts in children with lymphoproliferative malignancies (which includes leukemia and lymphoma) was 15%, compared to 8% in the control group. Logistic regression analysis revealed that children with leukemia and other lymphoproliferative malignancies were twice as likely to have an abnormal rib count compared to controls. While this supports a broader association between RAs and leukemia, the study did not specifically focus on CRs, making direct comparisons with Schumacher et al. (1992) and Merks et al. (2005) more challenging [7, 8]. In contrast, Zierhut et al. (2011) provided a more nuanced perspective. While their study confirmed an overall link between RAs and an increased risk of childhood cancers, the specific association between CRs and leukemia did not reach statistical significance. Notably, children with AML had a significantly higher likelihood of RAs, with an adjusted OR of 2.29 (95% CI: 1.02–5.13). However, when CRs were analyzed separately, the association weakened (adjusted OR = 1.63, 95% CI: 0.55–4.80), failing to reach statistical significance. This suggests that while RAs in general may be linked to leukemia, CRs alone may not be a consistent marker for the disease [12]. Overall, the studies by Schumacher et al. (1992) and Merks et al. (2005) suggest a potential association between CRs and leukemia [7, 8, 11]. However, Zierhut et al. (2011) cast doubt on the specificity of this relationship, indicating that while RAs may be more common in leukemia patients, CRs alone may not be a reliable marker [12]. Further research is needed to clarify whether CRs are a developmental indicator of leukemia risk or if their observed association is due to broader skeletal anomalies linked to pediatric malignancies. Sarcomas Sarcomas comprise a diverse group of mesenchymal tumors, with over 100 distinct diagnostic types. This variability is evident through both light microscopy and gene expression analysis. Even within the same histological category, there can be substantial differences in biological behavior [22]. Sarcomas are generally classified into two main types: soft tissue sarcomas and primary bone sarcomas, each requiring unique staging and treatment strategies. Soft tissue sarcomas are typically categorized based on genetic alterations and microscopic examination of hematoxylin-eosin–stained tissue, where morphological features resembling normal tissues are identified. Additionally, sarcomas are further assessed by histologic grade. The three key prognostic factors are the tumor’s grade, size, and primary location [22]. Sarcomas usually arise spontaneously, but certain risk factors have been identified. Exposure to ionizing radiation, often from cancer treatments, increases the likelihood of sarcomas, typically appearing 7-10 years after exposure. Other risk factors include chronic lymphedema, exposure to chemicals like vinyl chloride, and infection with human herpesvirus 8, which is linked to Kaposi sarcoma [22]. Several genetic syndromes also elevate sarcoma risk. Neurofibromatosis type 1 leads to benign and malignant nerve sheath tumors, while neurofibromatosis type 2 is associated with meningiomas and cranial nerve schwannomas. Gardner syndrome increases the risk of desmoid tumors, and hereditary retinoblastoma raises the likelihood of osteosarcoma and soft tissue sarcomas later in life. Li-Fraumeni syndrome, caused by TP53 mutations, also predisposes individuals to sarcomas [22]. Schumacher et al. (1992) found a significant association between CRs and sarcomas, reporting their presence in 24.5% of patients with soft tissue sarcomas (p &lt; 0.001) and 17.1% of those with Ewing sarcoma (p &lt; 0.01), compared to only 5.5% in the control group. These findings suggest a potential developmental or genetic link between CR anomalies and sarcomas, possibly due to early mesodermal development disruptions, which influences skeletal and soft tissue formation [7]. However, later studies did not consistently replicate these findings. Merks et al. (2005) found much lower rates of CRs in sarcoma patients, with 7.4% of rhabdomyosarcoma cases (5/68, p = 0.687), 6.3% of osteosarcoma cases (3/48, p = 0.973), and 7.7% of Ewing sarcoma cases (3/39, p = 0.692). None of these differences were statistically significant, suggesting that the initial association reported by Schumacher et al. (1992) may have been due to sample variation or other confounding factors. The stark contrast between these two studies raises questions about whether the observed link is truly biologically relevant or if it was an artifact of study design or population differences [8]. Loder et al. (2007) examined RAs in solid tumors, including osteosarcoma, rhabdomyosarcoma, and Ewing sarcoma, finding that 13% of cases exhibited RAs. However, this association was not statistically significant (p = 0.15), suggesting that while RAs may be more common in children with cancer, they do not appear to be strongly associated with sarcomas specifically [11]. Similarly, Zierhut et al. (2011) identified a general link between RAs and childhood cancers but did not find a significant correlation between CRs and sarcomas. This further weakens the hypothesis that CRs are a marker for sarcoma risk [12]. Overall, while the Schumacher et al. (1992) study initially suggested a strong association between CRs and sarcomas, more recent studies, including those by Merks et al. (2005), Loder et al. (2007), and Zierhut et al. (2011), have not confirmed this relationship [7, 8, 11, 12]. The inconsistencies in findings suggest that if a link does exist, it may be weaker than initially thought or influenced by confounding factors. Further research with larger sample sizes and refined methodologies is needed to clarify whether CRs have any true predictive value for sarcoma development. Wilms tumor Wilms tumor (WT), or nephroblastoma, is a malignant solid tumor that arises from the primitive renal bud. It is the most common primary renal tumor in the urogenital tract of children and typically occurs unilaterally in 90–95% of cases. However, it can also present bilaterally or multicentrically, particularly in cases associated with genetic factors, occurring either simultaneously (synchronously) or at different times (metachronously). WT accounts for approximately 2% to 6% of all childhood cancers [23]. Both genetic and environmental factors influence the development of WT. Genetic mutations play a crucial role, particularly in the WT1 and WT2 genes, which are vital for kidney development [23]. WT1 mutations are linked to syndromic forms of WT, such as WAGR and Denys-Drash syndromes, while WT2 abnormalities are associated with Beckwith-Wiedemann syndrome. Additionally, mutations in CTNNB1 (β-catenin), TP53, and microRNAs contribute to tumor development. Environmental factors, including parental exposure to pesticides before conception or during pregnancy, may increase the risk, though their precise impact remains unclear. WT is frequently associated with congenital syndromes involving developmental abnormalities [23]. Schumacher et al. (1992) identified a significant association between CRs and WT, reporting that 23.5% of children with WT had CRs, compared to only 5.5% in the control group (p &lt; 0.001). This strong statistical significance suggests a potential developmental link between skeletal anomalies and WT [7]. However, Merks et al. (2005) found that 9.8% of children with WT had CRs, compared to 6.1% in the control group, but the difference was not statistically significant (p = 0.115). This suggests that while CRs may be more common in WT patients, the association is not robust enough to be considered a reliable marker [8]. Similarly, Zierhut et al. (2011) reported a statistically significant increase in overall RAs among children with renal tumors, including WT. However, when analyzing CRs specifically, they did not find a significant association, further casting doubt on their role as a consistent indicator of WT [12]. Loder et al. (2007) provided additional support for a general link between RAs and pediatric malignancies but did not specifically analyze CRs in WT patients. This broader pattern suggests that skeletal anomalies may be associated with childhood cancers but does not confirm a direct link between CRs and WT [11]. These findings indicate that while there is some evidence of a relationship between skeletal anomalies and WT, the inconsistent association with CRs suggests that other factors may be at play. Additional research is needed to explore the genetic and developmental mechanisms underlying these observations, which could provide further insights into the etiology of WT and its potential links to congenital anomalies. Germ Cell Tumors Germ cell tumors (GCTs) are the most diverse childhood neoplasms. The majority are benign teratomas, presenting as heterogeneous masses with cystic and solid components. However, approximately 20% of GCTs are malignant, accounting for 3% of pediatric cancers. Malignant GCTs can occur at any age but follow a bimodal distribution, primarily affecting infants and adolescents [24]. These tumors can develop in various anatomical locations, including the gonads, sacrococcygeal region, mediastinum, retroperitoneum, and other para-axial sites. They are believed to originate from a common progenitor germ cell but exhibit diverse histologies, such as endodermal sinus tumor (yolk sac tumor), germinoma (dysgerminoma or seminoma), embryonal carcinoma, and choriocarcinoma. Different histological types often coexist within a single tumor, with approximately 25% of pediatric GCTs containing multiple histologic components [24]. Malignant GCTs have specific genetic predispositions, and genome-wide association studies (GWAS) have identified single-nucleotide polymorphisms (SNPs) in genes such as KITLG, SPRY4, DMRT1, and TERT, which are linked to the development of testicular GCTs [25]. Schumacher et al. (1992) investigated the relationship between CR anomalies and yolk sac tumors, a type of GCT, but did not find a significant association. The prevalence of RAs in patients with yolk sac tumors was 3.4%, which was not significantly different from the normal population (5.5%). This finding suggests that, unlike other pediatric malignancies, GCTs may not share a strong developmental link with skeletal anomalies [7]. In contrast, Merks et al. (2005) reported a statistically significant association between CR anomalies and GCTs, with 14.7% of GCT patients exhibiting CRs compared to 6.1% in controls (p = 0.046). This suggests a potential genetic or developmental link between GCTs and skeletal anomalies, though the mechanisms underlying this association remain unclear. The higher prevalence observed in this study raises the possibility that certain genetic mutations or disruptions in embryonic development may predispose individuals to both conditions [8]. Loder et al. (2007) did not specifically analyze CRs in relation to GCT. However, their study demonstrated a broader statistically significant association between RAs and childhood malignancies. Children with cancer had a higher prevalence of RAs (18%) compared to the control group (8%), with a p-value of 0.003. While this finding supports a general link between skeletal anomalies and pediatric cancers, it does not establish a direct connection between CRs and GCTs [11]. Similarly, Zierhut et al. (2011) did not specifically report a link between CR and GCTs. The absence of a reported association with GCTs suggests that these tumors may not be as strongly linked to skeletal anomalies as other childhood malignancies [12]. Overall, while some studies indicate a potential link between CR anomalies and GCTs, the evidence remains inconsistent. Merks et al. (2005) provided the most substantial support for an association, but findings from Schumacher et al. (1992) and Zierhut et al. (2011) did not confirm this relationship [7, 8, 12]. Additional research is needed to determine whether CR anomalies can serve as a marker for GCTs or if the observed association is due to other underlying developmental factors. Other Rib Anomalies Associated with Cancer Numerical RAs, such as having fewer than 24 ribs, were also found to be more common in children with malignancies. Loder et al. (2007) reported that 18% of children with malignancies had an abnormal rib number compared to 8% of controls. Among specific cancer types, neural tumors had the highest incidence of abnormal rib counts (35%), followed by lymphoproliferative malignancies (15%) and solid tumors (13%) [11]. Similarly, Zierhut et al. (2011) found that children with AML, renal tumors, and hepatoblastoma had a significantly higher likelihood of having an abnormal rib count (p = 0.008) [12]. Rib bifurcations, which involve rib splitting into two separate structures, have also been linked to certain malignancies. Schumacher et al. (1992) reported that 4.5% of neuroblastoma patients exhibited rib bifurcations, a rate four times higher than that of the normal population (1.07%). This suggests that developmental abnormalities affecting rib segmentation may be related to tumorigenesis in neural crest-derived cancers such as neuroblastoma [7]. Rib synostosis, or rib fusion, has also been observed in childhood malignancies. Though relatively rare, this anomaly was documented in some studies. Schumacher et al. (1992) found that 0.5% of cancer patients had rib synostosis compared to none in the control group, while Merks et al. (2005) identified synostosis in 0.2% of cancer patients. Notably, leukemia and brain tumor patients were more likely to present with this anomaly [7, 8]. Additionally, rib hypoplasia (underdeveloped ribs) and aplasia (missing ribs) have been reported in association with various malignancies. Loder et al. (2007) found that children with malignancies were more likely to have fewer ribs, with 44 cases of 22 ribs and 10 cases of 23 ribs, compared to just 16 cases in the control group (p = 0.003) [11]. Schumacher et al. (1992) also reported that 1.2% of cancer patients had rib aplasia or hypoplasia, compared to 0.5% in controls (Table 1) [7]. Table 1. Association Between Rib Anomalies and Childhood Malignancies. Study Year Sample Size Key Findings Cancer Types Types of Rib Anomalies Conclusion Schumacher et al. [7] 1992 1000 cancer, 200 controls Rib anomalies more common in cancer patients (21.8% vs. 5.5% in controls). Neuroblastoma had the highest rate (33%). Neuroblastoma, Brain tumors, Leukemia, Soft tissue sarcoma, Wilms' tumor, Ewing sarcoma CRs, Bifurcations, Synostoses, Aplasia/Hypoplasia Rib anomalies may be linked to tumor development. Further research needed. Merks et al. [8] 2005 906 cancer, 881 controls CRs were more common in cancer patients (8.6% vs. 6.1% in controls), particularly in leukemia and astrocytoma. ALL, Astrocytoma, Germ Cell Tumors CRs, Bifid ribs, Rib synostosis Rib anomalies could indicate genetic mutations linked to cancer. Loder et al. [11] 2007 218 cancer, 200 controls Rib anomalies were more frequent in cancer patients (18% vs. 8%). Neural tumors had the highest incidence (35%). Neural tumors, Lymphoproliferative malignancies, Solid tumors Fewer than 24 ribs, Rib fusions, Bifurcations Possible link between rib anomalies and homeobox gene mutations. Zierhut et al. [12] 2011 625 cancer, 1499 controls Significant association found between rib anomalies and leukemia, renal tumors, and hepatoblastoma. AML, Renal tumors, Hepatoblastoma Fewer or more than 24 ribs, CRs, Bifurcations Rib anomalies could be a marker for cancer predisposition. More research needed. ALL: Acute Lymphoblastic Leukemia, AML: Acute Myelogenous Leukemia, CR: Cervical rib Future Perspectives Future research should focus on large-scale, multicenter studies to validate these findings and establish whether RAs, particularly numerical variations, bifurcations, synostoses, and hypoplasia, can be predictive markers for specific cancers. Advances in imaging technologies, such as high-resolution computed tomography and magnetic resonance imaging, may enhance the accuracy of rib anomaly detection and contribute to more precise correlations with cancer risk. Genetic and molecular studies are also needed to explore the role of Hox genes and other developmental pathways in skeletal formation and oncogenesis. Identifying genetic mutations contributing to RAs and tumor development could lead to novel insights into cancer predisposition syndromes. Additionally, investigating the role of environmental and epigenetic factors in the occurrence of RAs and malignancies may provide a more comprehensive understanding of their shared etiology. From a clinical perspective, integrating rib anomaly screening into routine pediatric check-ups for high-risk populations could help in early cancer detection. However, before implementing such screening, further studies must determine the predictive value of RAs and whether they can be used as independent risk markers. Ultimately, interdisciplinary collaboration between geneticists, radiologists, oncologists, and developmental biologists will be crucial in advancing understanding of the link between RAs and childhood cancer. As research continues, these efforts may pave the way for novel diagnostic strategies and targeted therapies for pediatric malignancies. Conclusion CRs may serve as valuable indicators of underlying genetic and developmental abnormalities linked to pediatric cancers. Understanding these connections could ultimately contribute to improved cancer screening, early diagnosis, and personalized treatment strategies for children at risk. Declarations Conflicts of interest: The authors have no conflicts of interest to disclose. Ethical approval: Not applicable. Patient consent (participation and publication): Not applicable. Funding: The present study received no financial support. Acknowledgements: None to be declared. Authors' contributions: FHK and BAA were significant contributors to the conception of the study and the literature search for related studies. HAN and MNH involved in the literature review, study design, and manuscript writing. SKA, AKG, WNS, HSN, LJM, ASH, OMH, SOA, AHA, LAS and ADS were involved in the literature review, data collection, the study's design, and the critical revision of the manuscript. FHK and BAA confirm the authenticity of all the raw data. All authors approved the final version of the manuscript. Use of AI: Perplexity (Deep Research) and ChatGPT (GPT-4.5) were used to assist in language editing and improving the clarity of the manuscript. All content was reviewed and verified by the authors. Authors are fully responsible for the entire content of their manuscript. Data availability statement: Not applicable.

THU0002 Fine mapping and expression studies of the 12Q13-14 locus associated with rheumatoid arthritis

Wilms Tumor

BackgroundOverexpression of carbonic anhydrase (CA IX) is associated with poor survival in several adult-type cancers but its expression is undocumented in Wilms tumour (WT), the most common tumour of the paediatric kidney.MethodsCA9 expression was measured using polymerase chain reaction (PCR) in 13 WTs and matched-paired non-neoplastic kidneys (NKs). CA IX and hypoxia-inducible factor-1 α-subunit (HIF-1α) protein were quantified in 15 matched-paired WTs and NKs using enzyme-linked immunosorbent assays. CA IX and HIF-1α were localised by immunostaining tissue sections of 70 WTs (untreated WTs, n = 22; chemotherapy-treated WTs, n = 40; relapsed/metastatic WTs, n = 8). CA IX-positive untreated WTs (n = 14) were immunostained for vascular endothelial growth factor (VEGF), glucose transporter-1 (GLUT1) and CD31. Double staining for CA IX and CD31 was performed in WTs (n = 14).ResultsCA9 full length (FL) was significantly up-regulated in WTs compared to NKs (p = 0.009) by real-time PCR. Conventional PCR showed expression of alternative splice variant in all NKs and WTs but FL in WTs only. WTs showed a 2-fold increase in CA IX protein over NKs (p = 0.01). HIF-1α levels were up-regulated in WTs compared to NKs, although the difference was not statistically significant (p = 0.09). CA IX and HIF-1α immunolocalisation were observed in 63% and 93% of WTs, respectively. The median fraction of cells staining positively for CA IX and HIF-1α was 5% and 22%, respectively. There was no significant association between the expression of either CA IX or HIF-1α and clinicopathological variables in WTs resected following chemotherapy. VEGF and GLUT1 immunoreactivity was seen in 94% and 100% with the median fraction of 10% and 60% respectively. Co-expression and co-localisation of all four hypoxia markers was seen in 7/14 and 6/14 cases respectively. CA IX was seen in well vascularised areas as well as in the peri-necrotic areas.ConclusionsCarbonic anhydrase 9 (mRNA and protein), and HIF-1α protein are overexpressed in a significant portion of WTs. No significant association was detected between the expression of either CA IX or HIF-1α and clinicopathological variables in WTs resected following chemotherapy. Cellular localisation studies in untreated WTs suggest that CA IX and HIF-1α are regulated by hypoxia and non-hypoxia mechanisms.

Nephroblastomatosis is a rare pre-neoplastic lesion defined as the presence of multiple nephrogenic rests. These are abnormal foci of persistent embryonal cells beyond 36 weeks’ gestation that are thought to be precursors for the development of Wilms tumor. Nephrogenic rests are seen in approximately 1% of pediatric autopsy series. Nephrogenic rests and nephroblastomatosis represent a spectrum of the same disease and the distinction between the two is somewhat arbitrary. There are no formal quantitative criteria that determine how many nephrogenic rests constitute nephroblastomatosis. The nephrogenic rests are divided into four categories in the pathology literature: perilobar, intralobar, combined and diffuse, depending on their location within the renal parenchyma. On imaging, nephroblastomatosis is best classified as multifocal or diffuse. Virtually all cases of bilateral Wilms tumor have associated multifocal nephroblastomatosis. Advances in imaging have increased our ability to detect small renal lesions in situ and, therefore, have played an increasingly significant role in the preoperative diagnosis and postoperative management of nephroblastomatosis and Wilms tumor. Imaging studies are essential in the diagnosis of these lesions and their evaluation over time to detect transformation into Wilms tumor. State-ofthe-art imaging with contrast-enhanced CT and MRI routinely detects lesions as small as 5 mm in diameter. Nephroblastomatosis is considered a predisposing condition to Wilms tumor development both in the ipsilateral and contralateral kidney. Identifying and distinguishing between nephroblastomatosis and Wilms tumor is critical because they imply distinct prognoses and treatment decisions. Differentiation between Wilms tumor and nephroblastomatosis is based on histological evaluation of biopsy combined with imaging studies. Fine-needle aspiration cytology is of limited value in the assessment of these lesions, as cytology is not able to distinguish nephroblastomatosis from Wilms tumor. The anatomical location of nephrogenic rests varies as well as the pattern of their distribution. Importantly, multifocal nephroblastomatosis has a stronger association with Wilms tumor than the diffuse type. The diffusely hyperplastic perilobar nephroblastomatosis has a characteristic appearance that is identified as peripheral confluent masses distorting and compressing the kidney with a thick rind of uniform abnormal tissue. On CT and MR imaging, both types appear similar to the renal cortex on nonenhanced scans. After contrast administration, NRs become markedly hypodense on CT and hypointense on MRI in comparison with the intensely enhancing renal parenchyma. Although there are no absolute imaging criteria to differentiate nephrogenic rests and nephroblastomatosis from Wilms tumor, nephrogenic rests and nephroblastomatosis can be differentiated from Wilms tumor in the same kidney, as Wilms tumors tend to be larger and more heterogeneous and demonstrate some contrast enhancement. Gadolinium-enhanced T1-weighted MRI is currently touted as the optimal imaging approach for detecting nephrogenic tissue, although US and CT are commonly Disclaimer Dr. Grattan-Smith has no financial interests, investigational or off-label uses to disclose.

Wilms tumor is the most common embryonal renal malignancy in children. WDR4 is an indispensable noncatalytic subunit of the RNA N7-methylguanosine (m7G) methyltransferase complex and plays an essential role in tumorigenesis. However, the relationship between polymorphisms in the WDR4 gene and susceptibility to Wilms tumor remains to be fully investigated. We performed a large case-control study involving 414 patients and 1199 cancer-free controls to investigate whether single nucleotide polymorphisms (SNPs) in the WDR4 gene are associated with Wilms tumor susceptibility. WDR4 gene polymorphisms (rs2156315 C > T, rs2156316 C > G, rs6586250 C > T, rs15736 G > A, and rs2248490 C > G) were genotyped using the TaqMan assay. In addition, unconditioned logistic regression analysis was performed, odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the association between WDR4 gene SNPs and Wilms tumor susceptibility as well as the strength of the associations. We found that only the rs6586250 C>T polymorphism was significantly associated with an increased risk of Wilms tumor (adjusted OR=2.99, 95% CI = 1.28-6.97, P = 0.011 for the rs6586250 TT genotype; adjusted OR=3.08, 95% CI = 1.33-7.17, P = 0.009 for the rs6586250 CC/CT genotype). Furthermore, the stratification analysis revealed that patients with the rs6586250 TT genotype and carriers with 1-5 risk genotypes exhibited statistically significant associations with increased Wilms tumor risk in specific subgroups. However, the rs2156315 CT/TT genotype was identified as having a protective effect against Wilms tumor in the age >18 months subgroup compared with the rs2156315 CC genotype. In brief, our study demonstrated that the rs6586250 C > T polymorphism of the WDR4 gene was significantly associated with Wilms tumor. This finding may contribute to the understanding of the genetic mechanism of Wilms tumor.