Malignant Cell Tumors Research Articles

Integrative analysis of single-cell and bulk multi-omics data to reveal subtype-specific characteristics and therapeutic strategies in clear cell renal cell carcinoma patients.

Background: Kidney renal clear cell carcinoma (KIRC) is the most prevalent subtype of malignant renal cell carcinoma and is well known as a common genitourinary cancer. Stratifying tumors based on heterogeneity is essential for better treatment options. Methods: In this study, consensus clusters were constructed based on gene expression, DNA methylation, and gene mutation data, which were combined with multiple clustering algorithms. After identifying two heterogeneous subtypes, we analyzed the molecular characteristics, immunotherapy response, and drug sensitivity differences of each subtype. And we further integrated bulk data and single-cell RNA sequencing (scRNA-Seq) data to infer the immune cell composition and malignant tumor cell proportion of subtype-related cell subpopulations. Results: Among the two identified consensus subtypes (CS1 and CS2), CS1 was enriched in more inflammation-related and oncogenic pathways than CS2. Simultaneously, CS1 showed a worse prognosis and we found more copy number variations and BAP1 mutations in CS1. Although CS1 had a high immune infiltration score, it exhibited high expression of suppressive immune features. Based on the prediction of immunotherapy and drug sensitivity, we inferred that CS1 may respond poorly to immunotherapy and be less sensitive to targeted drugs. The analysis of bulk data integrated with single-cell data further reflected the high expression of inhibitory immune features in CS1 and the high proportion of malignant tumor cells. And CS2 contained a large number of plasmacytoid B cells, presenting an activated immune microenvironment. Finally, the robustness of our subtypes was successfully validated in four external datasets. Conclusion: In summary, we conducted a comprehensive analysis of multi-omics data with 10 clustering algorithms to reveal the molecular characteristics of KIRC patients and validated the relevant conclusions by single-cell analysis and external data. Our findings discovered new KIRC subtypes and may further guide personalized and precision treatments.

Unusual Presentation: Nephroblastoma/Wilms tumor in an Adult – A Case Report

Abstract Introduction/Objective Nephroblastoma/Wilms tumor is a common renal tumor primarily observed in children, and its occurrence in adults is exceedingly rare. This rarity contributes to the diagnostic challenges encountered in adults. Here, we present a case of a 32-year-old male diagnosed with biphasic nephroblastoma/Wilms tumor in the kidney, with liver and lung metastases. Methods/Case Report A 32-year-old male, without significant past medical history, presented with the chief complaint of abdominal pain for 2-3 weeks. Imaging studies revealed a substantial 17.5 cm kidney lesion accompanied by numerous lung and liver lesions. A liver biopsy indicated a small blue cell tumor, morphologically and immunophenotypically, (positive WT1) resembling nephroblastoma, with a strong suspicion of metastasis. Subsequent kidney biopsy confirmed a small blue cell malignant tumor demonstrating biphasic features, including blastema and epithelial components forming tubular structures similar to the liver biopsy, predominantly showing the blastemal component. The renal tumor biopsy supported the diagnosis of nephroblastoma. Despite chemotherapy, the patient passed away two months after the initial liver tumor biopsy. Results (if a Case Study enter NA) NA Conclusion Diagnosing nephroblastoma in adults poses significant challenges, particularly when initial presentations involve metastases. The occurrence of pediatric tumors in adulthood, though rare, should be considered in the diagnostic process after exhausting other possibilities. It is also important to note that the clinical presentation of pediatric tumors in adults may deviate from typical patterns. While Wilm’s tumor commonly presents as a painless, palpable abdominal mass in pediatric cases, adults may exhibit abdominal pain as the predominant symptom, as present in our case.

Spitz melanoma with MAP3K8::ABLIM1 rearrangement: a case report with review of the literature

BackgroundSpitz tumors are relatively uncommon melanocytic lesions, typically affecting a relatively younger population but can be encountered at any age. They are characterized by a proliferation of melanocytes with epithelioid and/or spindled cytomorphology features, and interpretation is often challenging. The majority of these tumors are driven by kinase fusions or HRAS mutations. MAP3K8 fusions, although rare, are characteristic genomic events in Spitz tumors, especially in more atypical or malignant lesions.Case presentationHere, we present the case of a 43-year-old woman with a clinically cystic mass in her right groin, histologically characterized as a spindle and epithelioid cell malignant tumor. Immunohistochemistry revealed diffuse expression of S100 protein, tyrosinase and SOX10, patchy weak PRAME, HMB45 and Melan-A reactivity, and negative staining for BRAF V600E. Next-generation sequencing analysis revealed the presence of a MAP3K8::ABLIM1 fusion gene, as well as GRIN2A and TERT promoter mutations. The morphology, immunohistochemistry and molecular analysis confirmed Spitz melanoma with molecular features suggesting a worse prognosis.ConclusionThis case introduces a novel fusion partner of MAP3K8 in the context of Spitz melanoma and expands the morphologic and molecular spectrum of Spitz melanoma.

Low-Dose Treatment with Epirubicin, a Novel Histone Deacetylase 1 Inhibitor, Exerts Anti-leukemic Effects by Inducing Ferroptosis

AimsLeukemia is hematopoietic stem cell malignant tumor with poor outcomes. Histone deacetylase 1 (HDAC1) is highly expressed in leukemia and current HDAC1 inhibitors have clinical limitations in leukemia therapy. Therefore, novel HDAC1 inhibitor is imperative to being found and its mechanism needs to be further explored. Materials and methodsNovel HDAC1 inhibitors were discovered through drug virtual screening. CCK-8, EdU and soft agar assay were used to assess the anti-leukemic effect of the candidate HDAC1 inhibitor. ROS, lipid peroxidation, intracellular Fe2+ and LIP assay were employed to verify cell ferroptosis. Additionally, a xenograft model was performed to explore the efficacy and safety of candidate HDAC1 inhibitor in vivo. ResultsHDAC1 might be a promising therapeutic target for leukemia and Epirubicin (Epi) could be used as a potential HDAC1 inhibitor. Low-dose Epi exhibited good anti-leukemic effects by inhibiting cell proliferation, DNA synthesis and colony formation. Low-dose Epi could induce ferroptosis by triggering lipid peroxidation, which was better than that treated with current HDAC1 inhibitors Chidamide or Vorinostat, ROS generation and Fe2+ overload in leukemia cells. Mechanistically, low-dose Epi induced ferroptosis by targeting amino acid metabolism and iron metabolism. Similar results were found in a xenograft model in NOG mice with a good safety profile. ConclusionOur study demonstrated that Epi might be used as a HDAC1 inhibitor. Low-dose Epi could inhibit tumor progression by inducing cell ferroptosis in vitro and in vivo. Thus, Epi administration with lower concentration may be much more favorable and safer in the treatment with leukemia.

Discovery of new non-covalent reversible BTK inhibitors: Synthesis, in silico studies, and in vitro evaluations

Bruton's Tyrosine Kinase (BTK) played a key role in the B cell antigen receptor (BCR) signaling pathway, and was considered a hotspot in the treatment of B cell malignant tumors and B cell immune diseases. There were 5 covalent irreversible inhibitors launched currently on the market, but C481S mutation was detected in most patients after administration. The approval of Pirtobrutinib (Jaypirca) by FDA in 2023 aroused great interest in the development of non-covalent and reversible BTK inhibitors. In order to solve the resistance of covalent irreversible inhibitors caused by C481S mutation, 11 reversible BTK inhibitors were designed based on screening in this article. The design, synthesis, in silico studies, and in vitro evaluations were performed for further verification. Among them, compound WS-11 showed best activity with IC50 of 3.9 nM for wild type, 2.2 nM for C481S mutation BTK, which was comparable to the positive control Pirtobrutinib. Furthermore, WS-11 would have a good druglikeness properties predicted by pkCSM and SwissADME, which provided a promising lead for further optimization and development.

CRISPR-mediated WNK4 point mutation aggravates tumor progression and weakens chemotherapy sensitivity in gastric cancer.

Gastric cancer (GC) is the fifth most common malignancy, the molecular targets of which have been increasingly explored in recent years. As a serine/threonine protein kinase, the role of WNK lysine deficient protein kinase 4 (WNK4) in GC was clarified in this study. Human GC lines AGS and MKN45 were stably transfected with a WNK4 mutant constructed by the CRISPR/Cas9 method and treated with cis-dichlorodiammine platinum (CDDP, 2 μg/mL) and 5-fluorouracil (5-FU, 5 μg/mL) for 48h. Tumor-bearing mice were established with 5×106 mutant-type AGS cells, and injected with 40 mg/kg WP1066, the inhibitor of signal transducer and activator of transcription 3 (STAT3), for 21 days. Cell malignant potential and tumor growth were assessed. STAT3 activation was identified by western blot and immunohistochemistry. The interaction between WNK4 and STAT3 was determined using co-immunoprecipitation and immunofluorescence co-localization. WNK4 mutation promoted proliferation and invasion, and upregulated the p-STAT3/STAT3 value in GC cells with/without 5-FU and CDDP treatments, while inhibiting apoptosis of GC cells without drug treatment. In tumor-bearing mice, WNK4 mutation accelerated tumor growth, increased levels of p-STAT3, STAT3, and p-STAT3/STAT3, and strengthened the co-immunoprecipitation and co-localizing with STAT3; however, these effects were reversed by WP1066 treatment. Through activating STAT3, WNK4 mutation impacts both the natural and drug-treated growth of GC cells or tumors, suggesting a new avenue for preclinical research.

Testicular Germ Cell Tumours - features and prospects of the novel tumour marker microRNA-371a-3p (M371 test): a narrative review

Testicular germ cell tumours (GCTs) represent a paradigm for the usefulness of serum tumour markers in clinical management of diseases. However, the tumour markers currently in use, beta human chorionic gonadotropin (bHCG), alpha fetoprotein (AFP) and lactate dehydrogenase (LDH) are expressed in less than 50% of GCT cases. In 2011, microRNA-371a-3p (currently named M371) was suggested as a novel marker for the first time. Chemically, microRNAS represent small RNA molecules consisting of 18-24 base pairs. Physiologically, these microRNAs play a prominent role in the epigenetic control of protein biosynthesis. M371 can be measured in serum with PCR-techniques.There is high level evidence for a 90% sensitivity and >90% specificity for GCTs of the marker M371. That high diagnostic accuracy is true for both seminoma and nonseminoma but not for the histologic subgroup of teratoma. Testicular tumours of non-germ cell origin and malignant neoplasms of other organs do not express the marker. M371 involves a very short half-life of <24 hours.The test does likely involve the prospects of providing substantial aid in clinical decision-making with respect to instances where improvement of GCT management is still required. In particular, the following clinical scenarios will probably benefit from the employment of the M371 test: (1) diagnostic work-up of incidentally detected small testicular masses with decision-making in regard to testis sparing surgery or full orchiectomy (2) simplifying the follow-up of GCT patients with sparing of imaging procedures in a number of cases; (3) diagnostic evaluation of retroperitoneal lymphadenopathy upon clinical staging; (4) diagnostic evaluation of false-positive elevations of classical tumour markers (AFP, bHCG); (5) rapid appraisal of therapeutic success or failure by means of the very short half-life of M371; (6) diagnostic evaluation of postchemotherapy residual masses particularly those in seminoma patients.The discovery and development of the novel tumour marker M371 probably represents a milestone progress in the history of the clinical management of testicular GCTs.

Histone lactylation facilitates hepatocellular carcinoma progression by upregulating endothelial cell-specific molecule 1 expression.

Hepatocellular carcinoma (HCC) is a common malignant tumor. Histone lactylation, a novel epigenetic modification, plays a crucial role in various cancers. However, the functional role and underlying mechanism of histone lactylation in HCC progression have not yet been investigated. Histone lactylation levels in HCC tissues and cells were assessed using a densitometric kit and western blot analysis. The role of histone lactylation in cell malignant phenotypes was determined through functional assays in vitro, and a xenograft tumor model was established to verify the function of histone lactylation in vivo. ChIP assay was performed to explore the interaction between histone lactylation and endothelial cell-specific molecule 1 (ESM1). Additionally, gain-and-loss-of-function assays were conducted to investigate the regulatory role of ESM1 in HCC pathogenesis. Histone lactylation levels were increased in HCC tissues and cells, and H3K9 lactylation (H3K9la) and H3K56 lactylation (H3K56la) were identified as the histone modification sites. We observed that H3K9la and H3K56la caused abnormal histone lactylation and were associated with poor prognosis. Functionally, histone lactylation was found to promote HCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in vitro. However, histone lactylation inhibition with 2-deoxy-d-glucose (2-DG) reduced the malignant phenotypes of HCC cells. In vivo, 2-DG treatment reduced tumor growth and metastasis in the HCC mouse model. Mechanistically, it was revealed that histone lactylation activated ESM1 transcription in HCC cells. ESM1 was expressed at a high level in HCC and exerted a carcinogenic role. Histone lactylation facilitates cell malignant phenotypes, tumor growth, and metastasis by upregulating ESM1 expression in HCC, which reveals the downstream molecular mechanism of histone lactylation and might provide a novel therapeutic target for HCC therapy.

Current situation and prospect of diagnosis and therapy of childhood acute leukemia in China

Acute leukemia is the most common hematopoietic stem cell malignant tumor in children, which ranks in the top one of the incidence of tumor in children, it is a major disease that affects the growth and survival of children. With the continuous improvement of medical diagnosis and treatment and the extensive development of immunotherapy, the survival rate and quality of life of children with acute leukemia have been significantly improved. In recent years, three cooperative groups of childhood leukemia have been established in China, and a series of high-level research results have been published. In the future, efforts should be made to promote the process of standardization and homogenization in the diagnosis and treatment of children's acute leukemia, explore the monitoring targets of sensitive residual diseases, and find the best treatment for refractory/recurrent cases. Speeding up the clinical research of new drugs will be an urgent problem and development direction in the field of acute leukemia diagnosis and treatment in children.

EIF4A3-Induced CircDHTKD1 regulates glycolysis in non-small cell lung cancer via stabilizing PFKL.

Lung cancer (LC) is one of the malignancies with the highest incidence and mortality in the world, approximately 85% of which is non-small cell lung cancer (NSCLC). Circular RNAs (circRNAs) exert multiple roles in NSCLC occurrence and development. The sequencing results in previous literature have illustrated that multiple circRNAs exhibit upregulation in NSCLC. We attempted to figure out which circRNA exerts an oncogenic role in NSLCL progression. RT-qPCR evaluated circDHTKD1 level in NSCLC tissue specimens and cells. Reverse transcription as well as RNase R digestion assay evaluated circDHTKD1 circular characterization in NSCLC cells. FISH determined circDHTKD1 subcellular distribution in NSCLC cells. Loss- and gain-of-function assays clarified circDHTKD1 role in NSCLC cell growth, tumour growth and glycolysis. Bioinformatics and RIP and RNA pull-down assessed association of circDHTKD1 with upstream molecule Eukaryotic initiation factor 4A-III (EIF4A3) or downstream molecule phosphofructokinase-1 liver type (PFKL) and insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) in NSCLC cells. Rescue assays assessed regulatory function of PFKL in circDHTKD1-meidated NSCLC cellular phenotypes. CircDHTKD1 exhibited upregulation and stable circular nature in NSCLC cells. EIF4A3 upregulated circDHTKD1 in NSCLC cells. CircDHTKD1 exerted a promoting influence on NSCLC cell malignant phenotypes and tumour growth. CircDHTKD1 exerted a promoting influence on NSCLC glucose metabolism. CircDHTKD1 exerts a promoting influence on NSCLC glucose metabolism through PFKL upregulation. RIP and RNA pull-down showed that circDHTKD1 could bind to IGF2BP, PFKL could bind to IGF2BP2, and circDHTKD1 promoted the binding of PFKL to IGF2BP2. In addition, RT-qPCR showed that IGF2BP2 knockdown promoted PFKL mRNA degradation, suggesting that IGF2BP2 stabilized PFKL in NSCLC cells. CircDHTKD1 exhibits upregulation in NSCLC. We innovatively validate that EIF4A3-triggered circDHTKD1 upregulation facilitates NSCLC glycolysis through recruiting m6A reader IGF2BP2 to stabilize PFKL, which may provide a new direction for seeking targeted therapy plans of NSCLC.

Neurofibromatosis to neoplasia transition: a rare case report of spindle cell malignant peripheral nerve sheath tumor with literature review

Introduction and Importance: Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue malignant tumor. MPNST in the spinal canal are rarely seen except in cases with NF1. But a long segment extradural spinal malignant spindle cell neoplasm has not been reported in current literature. Case Presentation: We present the first reported case of spinal malignant spindle cell neoplasm extended along the spine. The detected lesion is responsible for compressing various segments of the spinal cord, causing thinning of the cord and secondary stenosis of the spinal canal, leading to a condition known as multi-segment compression myelopathy. Clinical Discussion: MPNSTS are typically detected late due to nonspecific symptoms, with a higher incidence in extremities and a notable occurrence in unusual locations. Diagnosis relies on MRI and histopathology, with S_100 positivity as a neural marker. MPNSTs can arise from neurofibromas or Schwann cells, with a significant portion resulting from TP53 mutations or secondary to radiation exposure. Conclusion: This case stands out due to its unique presentation, characterized by a predominantly spindle cell morphology with certain epithelioid features. It is imperative to recognize this condition for an accurate diagnosis, emphasizing the spindle cell-type malignant peripheral nerve sheath tumor (MPNST) and highlighting its exceptionally poor prognosis.

The relationship between metabolite mediated immune regulatory imbalance and the occurrence of malignant tumors of bone and articular cartilage: a Mendelian randomization study.

This study aims to assess the causal relationship between immune cell characteristics and malignant tumors of bone and articular cartilage, focusing on the mediating role of metabolites. Using Mendelian randomization, we evaluated these relationships based on genetic variations to identify potential biomarkers and therapeutic targets. A two-sample Mendelian randomization analysis was conducted using GWAS data for immune cell features and 1,400 metabolites to investigate direct and mediating effects. Effective instrumental variables (IVs) were selected, and statistical analyses-including inverse variance weighting (IVW), weighted median, and mode-based methods-were performed using R software. This approach enabled the assessment of direct causal relationships as well as the potential mediating role of metabolites in the association between immune cell features and malignancies. Significant causal relationships were identified between 26 immune phenotypes and the risk of malignant tumors of bone and articular cartilage. Notably, the HLA DR+ NK cell phenotype SSC-A showed a positive correlation with the risk of these malignancies. Further analysis revealed causal relationships with 67 metabolites, 38 of which were positively correlated and 29 negatively correlated. Mediation analysis highlighted the role of immune surveillance and metabolic dysregulation in tumor development, as evidenced by the association between the immune phenotype SSC-A on HLA DR+ NK cells and the metabolite 5-hydroxyhexanoate. The findings suggest significant causal relationships between immune phenotypes and malignant tumors of bone and articular cartilage, with metabolites potentially mediating these relationships. These insights lay the groundwork for further research and could contribute to the development of new biomarkers and treatment strategies.

Renal CIC-LEUTX rearranged sarcoma with multiple pulmonary metastases: a case report and literature review

BackgroundCIC-rearranged sarcomas (CRS) are a group of heterogeneous tumors which mostly occur in the soft tissues of limbs and trunk, and are highly invasive with poor prognosis. Here, we describe a rare case of CRS that occurred in the left kidney with a CIC-LEUTX rearrangement.Case presentationA 45-year-old male was admitted to hospital with a dry cough for more than two months without obvious cause. Physical examination and laboratory tests revealed no notable abnormality. The CT scan demonstrated a mass in the left kidney and multiple nodules in both lungs. The percutaneous core needle biopsy showed similar histomorphology and immunophenotype of small round cell malignant tumors. Genetic test revealed a CIC-LEUTX gene fusion.ConclusionsWe present a rare primary renal CRS with multiple pulmonary metastases, and LEUTX is confirmed as the fusion partner of CIC gene for the first time in a renal case.

Spindle cell carcinoma of the larynx: a rare entity

Squamous cell carcinoma (SCC) is the commonest malignancy encountered in the larynx in the Indian population. Spindle cell carcinoma is an extremely rare malignant tumor and is a variant of SCC with a mesenchymal like malignant cell component. This is a case report of a 58 years old patient who presented with hoarseness of voice of 7 months duration. He was diagnosed to have a right vocal cord polypoidal growth with mobile vocal cords. He underwent direct laryngoscopy and biopsy of the lesion which was reported as spindle cell neoplasm/inflammatory myofibroblastic tumor (IMT). Immunohistochemistry (IHC) was carried out and confirmed the diagnosis of inflammatory myofibroblastic tumor. He was doing well and the follow up videolaryngoscopic examinations and PET CT were normal. At subsequent follow-up 19 months later, he was found to have a recurrent right vocal cord lesion. Direct laryngoscopy and biopsy was repeated along with laserization of the right vocal cord. Histopathology was reported as spindle cell malignant neoplasm. Immunohistochemistry was reported as spindle cell carcinoma. He was then sent for radiation therapy. The patient responded well to radiation and is tumor free at last follow-up. He has been advised regular follow-ups. Spindle cell carcinoma is an extremely rare laryngeal malignancy. It typically originates in the glottis. The treatment for spindle cell carcinoma includes surgery, radiation or a combination of these modalities. Its prognosis is worse than squamous cell carcinoma and patients require close follow-ups.

Tumor-Promoting Role of GNA14 in Colon Cancer Development.

Recent studies have shown that mutations in members of the G-protein α family contribute to the onset and progression of cancer. However, the role of GNA14 in CRC remains unknown. In this study, we examined the effect of GNA14 on CRC through genetic approaches in vitro and in vivo. We found that GNA14 knockdown by small interfering RNA (siRNA) inhibited the proliferation of CRC cells SW403 and HT29. Gna14 knockout mice developed normally without obvious abnormalities. However, the number of polyps in the small intestine was significantly reduced in Gna14 knockout mice compared to control mice after mating with ApcMin mice, a representative CRC mouse model. In particular, deletion of the Gna14 inhibited polyp growth, especially in the distal end of the small intestine. Histological examination showed that Gna14 knockout mice suppressed malignant tumor progression due to decreased proliferation and increased apoptosis in polyps compared to controls. In addition, GNA14 knockdown in CRC cells resulted in downregulation of ERK phosphorylation and β-catenin and β-catenin phosphorylation at S675. Similarly, ERK phosphorylation and phospho-β-catenin phosphorylation at S675 were decreased in polyps of Gna14 knockout mice. Collectively, these analyses show that GNA14 may accelerate CRC cell proliferation and malignant tumor progression through ERK and β-catenin pathways.

40 Comparison of contemporary management and outcomes of patients with transitional cell carcinomas and malignant Brenner tumors of the ovary

40 Comparison of contemporary management and outcomes of patients with transitional cell carcinomas and malignant Brenner tumors of the ovary

Cytological spectrum of testicular malignancies with histopathological correlation: A retrospective analysis.

Testicular malignancy is the most common solid organ cancer occurring in young men. The most common testicular malignancy is germ cell tumor. Extragonadal malignancies such as lymphomas are rare. Testicular fine-needle aspiration cytology (FNAC) in cancer is a bit controversial amidst fear of tumor seeding along the needle tract. Nevertheless, its largely safe, cost-effective technique providing a quick and fairly reliable diagnosis. A retrospective analysis of testicular malignancies on FNAC over a period of 9 years with cyto-histological correlation wherever possible was carried out. FNAC slides and cell blocks with immunocytochemistry wherever done were retrieved. A total of 74 cases were obtained. The age ranged from 1 year to 65 years. Infiltration by leukemia was the most common malignancy detected in pediatric population, while germ cell tumors were common amongst young adults and middle-aged men. In elderly, metastatic carcinoma, infiltration by lymphoma were identified. On FNAC, 38 cases were of leukemic infiltration, 27 of germ cell tumors (subtyped as mixed germ cell tumors-15 cases, seminoma-11 cases, and yolk sac tumor-1 case) with two cases each of non-Hodgkin lymphoma, Leydig cell tumor, metastatic adenocarcinoma, and one case each of metastatic small cell carcinoma, rhabdomyosarcoma, and malignant neoplasm. Histological correlation was available in 15/74 cases. Only 3 cases were discordant. Seeding of tumor along the needle tract was not seen. The current study deciphers the cytological spectrum of testicular malignancies on FNAC and highlights its importance as a reliable modality for a prompt diagnosis of testicular tumors guiding patient management.

Dysregulation of MiR-199a/IL8 pathway in chronic Cr (VI)-induced tumor growth and angiogenesis

Hexavalent chromium [Cr(VI)] is a well-known environmental carcinogen. Recent studies revealed that chronic exposure of human bronchial epithelial cells (BEAS-2B, B2B) to Cr(VI) activated several signaling pathways and induced cell malignant transformation and tumor growth. However, new mechanisms of Cr(VI) in inducing carcinogenesis remains to be elucidated. This study showed that miR-199a expression levels were significantly lower in Cr(VI)-transformed Cr-T cells. By using the mouse model, the expression levels of miR-199a were significantly decreased in blood samples and lung tissues of mice intranasally exposed to Cr(VI) for 12 weeks compared to the solvent exposure control. Overexpression of miR-199a inhibited tube formation and angiogenesis. C-X-C motif chemokine ligand 8 (CXCL8, IL8) levels were significantly higher in blood samples of Cr (VI)-exposed workers compared to normal workers, and forced expression of miR-199a in the cells suppressed IL8 levels. miR-199a suppression induced expression of hypoxia-inducible factor 1α (HIF-1α) and nuclear factor kappa B (NF-κB) p65 to increase IL8 expression. With animal experiment, the results showed that miR-199a overexpression inhibited tumor growth and angiogenesis through inhibiting IL8, HIF-1α and NF-κB p65 expression in vivo. These results show that miR-199a/IL8 pathway is important in Cr(VI)-induced carcinogenesis and angiogenesis.

EWING'S SARCOMA IN THE PREMAXILLA OF A PEDIATRIC PATIENT: A CASE REPORT

In August 2019, a 5-year-old female pediatric patient was diagnosed with primary non-metastatic Ewing sarcoma. She began chemotherapy treatment in September 2019, ending in November 2019. Subsequently, she was referred to a head and neck specialist, where a tumor was observed in the upper anterior alveolar edge. A biopsy was performed which confirmed Ewing´s sarcoma and showed an infiltrate in the entire premaxilla without posterior or midface involvement. Surgery for tumor resection was performed in March 2020, with a conclusive biopsy of small and round cell malignant neoplasm, consistent with Ewing´s sarcoma, the surgical margins were compromised, thus requiring complementary radiotherapy treatment. The rehabilitation was performed with a polypropylene obturator prosthesis in the premaxilla region. The patient returned for a check-up, without complaints, and was able to express herself in an intelligible manner, with her stomatognathic functions in balance. In August 2019, a 5-year-old female pediatric patient was diagnosed with primary non-metastatic Ewing sarcoma. She began chemotherapy treatment in September 2019, ending in November 2019. Subsequently, she was referred to a head and neck specialist, where a tumor was observed in the upper anterior alveolar edge. A biopsy was performed which confirmed Ewing´s sarcoma and showed an infiltrate in the entire premaxilla without posterior or midface involvement. Surgery for tumor resection was performed in March 2020, with a conclusive biopsy of small and round cell malignant neoplasm, consistent with Ewing´s sarcoma, the surgical margins were compromised, thus requiring complementary radiotherapy treatment. The rehabilitation was performed with a polypropylene obturator prosthesis in the premaxilla region. The patient returned for a check-up, without complaints, and was able to express herself in an intelligible manner, with her stomatognathic functions in balance.

Primary Nodal Merkel Cell Carcinoma: Rare Presentation

Merkel cell carcinoma (MCC) is a very rare high-grade neuroendocrine carcinoma that is frequently located in the skin. Although most cases are associated with Merkel cell polyomavirus, there are also cases in which the virus cannot be detected. The purpose of presenting the case of MCC with primary nodal involvement is due to its rare presentation. &#x0D; A 59-year-old male patient presented to the hospital with painless mass in the neck. Imaging analyses revealed necrotic lymphadenopathies on the neck, measuring up to 4.5 cm in size. After an explorative surgery with preliminary diagnoses of lymphoma and squamous cell carcinoma , samples taken from the excised mass showed high-grade neuroendocrine carcinoma morphology. In addition to neuroendocrine markers, CK7 and CK20 positivity were observed in the immunohistochemical tests performed. As a result, the case was evaluated in favor of MCC with negativity of markers performed to exclude other malignancies. Subsequently, a diagnosis of primary nodal MCC was made due to the absence of a different focus other than lymph node on PET imaging analysis.&#x0D; The differential diagnosis should be kept broad due to the histopathological morphology of small round cell malignant tumors. In addition in high-grade neuroendocrine carcinomas, the possibility of MCC should be ruled out especially if CK20 positivity is present. Although is has been reported that primary nodal MCC cases have a better clinical course compared to nodal metastatic cases with a known primary, there are limited case series studies on this topic. A multisystem approach is recommended for proper clinical management.