Frequent Cancer Research Articles

PSMC2 promotes glioma progression by regulating immune microenvironment and PI3K/AKT/mTOR pathway

BackgroundGlioma, the most frequent and malignant central nervous system (CNS) cancer, has a bad outcome. Proteasome 26S subunit ATPase 2 (PSMC2) is an essential part of the 26S proteasome and promotes the development of several tumors. However, the pathway and function of PSMC2 in glioma have not been unelucidated. MethodsThis study analyzed PSMC2 expression in glioma tissues and its predictive significance for patients. We examined the link between PSMC2 and DNA methylation, immune cell infiltration, tumor immune cycle, immune cell homeostasis, and immune checkpoints. Subsequently, immunohistochemistry and in vitro trials were employed to validate the expression, prognostic potential, and function of PSMC2 in glioma. The mechanisms of PSMC2 in glioma were further explored. ResultsOur study revealed that PSMC2 expression increased in glioma tissues contrasted with healthy tissues, and patients with high PSMC2 glioma exhibited poor overall survival (OS) compared to the low-PSMC2 group. Immune profile analysis revealed that PSMC2 was positively related to immunosuppressive cell infiltration and immune checkpoints and adversely related to the cancer immune cycle and immune cell homeostasis. In cell-based investigations, the inhibition of PSMC2 was found to effectively suppress the aggressiveness and proliferation of glioma cell lines while also enhancing cell cycle arrest and promoting cell death. Gene Set Enrichment Analysis (GSEA), Gene Set Variation Analysis (GSVA), and in vitro experiments showed that PSMC2 promoted glioma development through the PI3K/AKT/mTOR pathway. ConclusionsPSMC2 was upregulated in glioma and promoted cancer progression by modulating the tumor immune microenvironment, cancer cell biological behavior, immune cell homeostasis, and the PI3K/AKT/mTOR pathway, providing a new option to treat glioma.

The haemoglobin levels of patients with prostate cancer treated with radical radiotherapy

Introduction: The worldwide estimate points to prostate cancer as the second most frequent cancer in men worldwide, where radiotherapy has been an important modality of curative treatment in managing this neoplasia. The prevalence and impact of cancer-related anemia are not widely known, and it may be overlooked or considered clinically significant. It is believed that the outcomes and toxicity of radiotherapy in prostate cancer treatment may be influenced by blood hemoglobin levels. Objective: To evaluate hemoglobin levels in patients with prostate cancer before and after radiotherapy treatment. Methods: Retrospective, longitudinal study of patients diagnosed with malignant prostate neoplasms undergoing external radiotherapy. Hemoglobin levels were measured before radiotherapy and after treatment completion (20-40 days). Anemia was defined by the World Health Organization as men with values less than 13 g/dl. Prostate cancer recurrence risk classification was based on the National Comprehensive Cancer Network risk criteria. Results: Forty patients were evaluated with measurement of Hemoglobin levels before and after radiotherapy treatment. The mean age was 67 years. According to the risk group classification, 4 patients were low-risk (10%), 27 patients were intermediate-risk (67.5%), and 9 patients were high-risk (22.5%). The mean pre-radiotherapy Hemoglobin levels were 13.3 g/dL, and the mean post-radiotherapy Hemoglobin levels were 10.4 g/dL, p < 0.0001. Conclusion: In this study, a reduction in serum Hemoglobin levels was observed after radiotherapy, highlighting the need for better monitoring of these patients.

Evaluation of miR-130b-3p and miR-375 levels and telomere length with telomerase activity in prostate cancer

Prostate cancer (PC) is the most frequent cancer in males, as well as the second highest cause of cancer-related deaths in men. Differences in expression levels of miRNAs were linked with prostat cancer pathogenesis. qPCR was used to evaluate the expression of miR-130b-3p and miR-375 in Benign Prostate Hyperplasia (BPH (n = 20) and PC (n = 22, pre- and post-operative) patients plasma. Relative telomere lengths (RLTs) in genomic DNA isolated from plasma were measured with qPCR, and telomerase activity analyzed by the ELISA method. PSA levels of PC patients were greater than of BPH patients (p = 0.0473). miR-130b-3p and miR-375 levels were significantly lower in pre-operative specimens of PC patients according to BPH (p = 0,0362, p = 0.0168, respectively). Similarly, post-operative miR-375 levels were lower in PC patients than in BPH patients (p = 0.1866). BPH patients had shorter RTLs than PC patients in both pre- (p=0.0438) and post-operative (p=0.0297) specimens. Telomerase activity was higher in PC patients than BPH(p = 0.0129). Interestingly, telomerase activity was further increased after surgery (p = 0.0003). We aim to identify the levels of miR-130b-3p and miR-375 expression and their relationship with telomerase activity in PC patients. Our data suggest that miRNAs and telomere length (TL) with telomerase activity may play a role in regulating prostate tumorgenesis and may be used as biomarkers for PC diagnosis.

Abstract 3709: Single cell analysis from CSF of patients with suspected leptomeningeal metastasis

Abstract Introduction: Leptomeningeal metastases (LM) are diagnosed in up to 10% of metastatic cancer patients, the most frequent cancers being carcinomas of breast and lung or melanoma. Due to a dismal prognosis and an overall median survival of only four months new approaches for molecular analysis could help to identify individual treatment options. Material and Methods: In this study, we collected 28 cerebrospinal fluid (CSF) samples from patients with different primary tumors but suspected LM. CSF was divided in two parts for standard neuropathologic cytomorphology and detection of circulating tumor cells (CTCs) by using the CellSearch® CTC Kit, respectively. Subsequently, single Cytokeratin-positive CTCs were isolated for whole genome amplification by Ampli1TM and molecular analysis. Additionally, we were able to isolate cell-free DNA (cfDNA) from CSF in a subset of patients which we amplified by an adapted Ampli1TM library protocol. In a small subset of patients, we collected slices of formalin-fixed paraffin embedded (FFPE) primary tumors and systemic metastases for dissociation and isolation of pure subpopulations by DEPArrayTM technology. Isolated CTCs, cfDNA and subpopulations of tumor and stromal cells were analyzed for copy number variations (CNV) applying the Ampli1TM LowPass protocol on the Illumina MiSeqTM platform. Results: By comparing results from classical cytomorphology and CellSearch® workflow, we could find high concordance (24/28 samples) with a slightly higher tumor cell detection rate by CellSearch® (11 positive cases vs. 9 by cytomorphology). Importantly, we could confirm the malignant origin of isolated cells by CNV analysis in all patients positive in CellSearch® assay. Moreover, by comparing single cell data with cfDNA analysis of a subset of 20 samples, we could also detect a higher sensitivity for tumor detection in CTC-based analysis (8/20 cases positive) in comparison to cfDNA-based analysis (5/20 cases positive). In a comprehensive analysis of multiple samples of an individual patient, including CTCs and cfDNA from CSF at different time points, CTCs from blood and biopsies from multiple visceral metastasis, we could identify divergent genomic evolution between tumor cells from the central nervous syste Conclusion: In this proof-of-concept study we show that a liquid biopsy-based approach for single cell analysis from CSF holds potential for innovative diagnostic assays for patients with suspected LM. Combining CTC quantification with molecular single cell analysis could enable us to define predictive tests to select novel treatment options for patients with LM in the future. Citation Format: Caecilia Koestler, Giancarlo Feliciello, Florian Lueke, Kathrin Weidele, Saida Zoubaa, Peter Hau, Tobias Pukrop, Markus J. Riemenschneider, Christoph A. Klein, Bernhard Polzer. Single cell analysis from CSF of patients with suspected leptomeningeal metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3709.

Abstract 1457: Decoding the molecular mechanisms related to mutations in the GNAQ/11 and BAP1 genes in ocular melanoma

Abstract Uveal melanoma (UM) is the most frequent intraocular cancer in adults and 50% of patients develop liver metastases for which no treatment is effective. According to The Cancer Genome Atlas, 92% of cases are characterized by early mutations in two genes coding for alpha subunits of G protein coupled receptors (GPCR): G protein subunit alpha q (GNAQ) or 11 (GNA11). These mutations are mostly found in the codon Q209 causing a constitutive activation of different signaling pathways linked to cellular proliferation such as MAPK and PKC. Furthermore, a bi-allelic inactivation of the BRCA1 associated protein-1 (BAP1) is found in 83% of metastatic UM and causes a loss of function of this protein. Our hypothesis is that the inactivation of compensatory pathways in the absence of these proteins and the understanding of pathways essential only to mutated cells will pave the way for the identification of better therapeutic candidates specific to UM cancer cells (UMCCs) to prevent metastatic progression and improve treatment options. The research objectives include the identification of compensatory signaling pathways in the absence of GNAQ/11 and BAP1 using classical CRISPR/Cas9, the discovery of essential molecular mechanisms for the survival of mutated UMCCs using Prime Editing, and the identification and characterization of novel therapeutic targets using 3D in vitro and in vivo models. First, the electroporation optimization using an eGFP plasmid demonstrated an efficiency of 40-50% for normal choroidal melanocytes (NCM) and 60-80% for UMCCs Mel285. Subsequent transfection with CRISPR complexes resulted in an average editing efficiency of approximately 20% for GNAQ/11 and 60% for BAP1. Currently, we have successfully established a GNAQ knockout (GNAQ-KO) Mel285 cell line. The characterization and validation of this cell line were performed through sequencing and Western blotting, confirming the creation of stop codons and the absence of GNAQ expression. We observed an overactivation of the ERK1/2 pathway and an upregulation of beta-catenin in the Mel285 GNAQ-KO line. Additionally, we noted a decrease in proliferation, adhesion, and migration on collagen I. For Prime editing, we constructed three plasmids with desired mutations. Preliminary tests in HEK293T cells showed an insertion efficiency of 4%, 20%, and 10% for GNAQ, GNA11, and BAP1, respectively, following a single treatment. Finally, in vitro testing has been started for inhibitors targeting compensatory pathways involving beta-catenin (WIKI4) and ERK1/2 (ASN007), in combination with the GNAQ/11 inhibitor (FR900359). These tests are being conducted on various mutant UMCCs for GNAQ/11.A better understanding of the altered pathways in our GNAQ/11 or BAP1 mutant isogenic cell lines will help to identify new drugs targeting specifically UM cells. Citation Format: Aurelie Fuentes-Rodriguez, Andrew Mitchell, Joël Rousseau, Jacques P. Tremblay, Solange Landreville. Decoding the molecular mechanisms related to mutations in the GNAQ/11 and BAP1 genes in ocular melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1457.

Abstract 235: Application of high-grade serous ovarian cancer organoids in functional precision medicine

Abstract High-grade serous ovarian cancer (HGSC) is the most frequent and lethal ovarian cancer type. Despite responding favorably to first-line therapy, most HGSC patients eventually relapse. HGSC is characterized by high interpatient genomic heterogeneity and few recurrent mutations that could be used as therapeutic biomarkers. Thus, except the introduction of PARP inhibitors for BRCA1/2-mutated patients, there has been little progress with personalizing HGSC treatment. Functional precision medicine - tailoring personalized therapies based on functional assays on patient-derived cells - has been applied in cancer clinical trials to address this issue. Organoids - three-dimensional cell cultures, recapitulating aspects of original tumors’ structure and function - have often been used as models in these efforts. However, inefficient and time-consuming organoid derivation protocols have been hindering the application of HGSC organoids in functional precision medicine clinical trials, due to the short time during which the therapy must be selected. To address this, we here aimed to establish whether we could predict second-line therapy drug sensitivities in relapsed HGSC using organoids from tumor material from first-line therapy. We have previously derived a collection of 23 organoid models from 16 patients, sampled sequentially at different times of their treatment (1). Here, for several organoid primary-relapse pairs, we performed drug screens using a library of 370 compounds (approved, in clinical development or tool compounds). We found that 90% of the hit compounds in the primary organoids also were hits in the matched relapse-derived organoid models. In several patients, we observed a pronounced cytotoxicity of several cyclin-dependent kinase (CDK) inhibitors, all of which potently inhibit CDK9, including two selective inhibitors (AZD4573 and VIP152) in clinical development. Screening of CDK9 inhibitors in an extended panel of organoid models revealed that most organoids are sensitive to CDK9 inhibition in nanomolar range. CDK9 inhibitors also prevented organoid outgrowth in long-term culture (>1.5 month) in drug-free medium. Taken together, we demonstrate that HGSC organoids from material sampled during first-line treatment predict most drug sensitivities of relapse-derived organoids. This suggests a feasibility of functional precision approach for selection of second-line therapy using only primary tumor material, circumventing the problem of limited time available for the therapy choice after tumor sampling. This work also highlights that CDK9 inhibitors, currently in clinical development for hematological malignancies, are worthwhile to be explored in HGSC. 1. Senkowski et al. A platform for efficient establishment and drug-response profiling of high-grade serous ovarian cancer organoids. Developmental Cell (2023) Citation Format: Wojciech Senkowski, Laura Gall-Mas, Matias M. Falco, Yilin Li, Kari Lavikka, Aura Crispino, Jaana Oikkonen, Daria Bulanova, Yan-Jun Chen, Elena M. Doncel, Karolin Voßgröne, Erdogan P. Erkan, Jun Dai, Anastasia Lundgren, Jutta Huvila, Kaisa Huhtinen, Johanna Hynninen, Sampsa Hautaniemi, Anna Vähärautio, Krister Wennerberg. Application of high-grade serous ovarian cancer organoids in functional precision medicine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 235.

Abstract 6346: IgG engineered to target PIGR-mediated transcytosis specifically targets intracellular oncoproteins and abrogated tumor growth

Abstract Despite their long half-life, therapeutic antibodies are considered ineffective against intracellular antigens due to their perceived inability to penetrate epithelial cells. Using recombinant antibodies targeting common mutations in oncogenes, we have demonstrated that dimeric IgA, but not the same antibody on an IgG backbone, penetrates human epithelial cancer cells through PIGR-dependent directional transcytosis, specifically neutralizing mutated oncodrivers and expelling antigens outside the cell, bound to secretory IgA. Accordingly, targeting of KRASG12D abrogated tumor cell proliferation in cell culture assays. In vivo, KRASG12D-specific dIgA1 limited the growth of RASG12D-mutated ovarian and lung carcinomas, including in syngeneic tumor-bearing immunocompetent mice. Moreover, dIgA targeting of KRASG12D restricted tumor growth more effectively than small-molecule KRASG12D inhibitors, supporting the potential of this approach for the treatment of human cancers. Since producing dimeric IgA is more challenging than producing monomeric IgG, and because the half-life of IgA is shorter (4-7 days) than IgG (21 days), we have developed a new approach combining KRASG12D specific IgG with a peptide that could join PIGR and penetrates tumor cells through transcytosis, that showed the same effect than IgA controlling tumor growth. Our results provide a rationale for developing modified IgG cell-penetrating antibodies to effectively target common mutations in intracellular oncogenes that drive many aggressive and frequent human cancers. In addition, further experiments suggest that these antibodies could be effectively used to target tumors that have become resistant to existing KRAS inhibitors. Citation Format: Carmen Maria Anadon Galindo, Luis U. Lopez-Bailon, Ricardo A. Chaurio, Jessica A. Mine, Noah E. Plappert, Jose R. Conejo-Garcia. IgG engineered to target PIGR-mediated transcytosis specifically targets intracellular oncoproteins and abrogated tumor growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6346.

Abstract 2673: Copper chelation overcomes the immunosuppressive neuroblastoma microenvironment to potentiate anti-GD2 antibody therapy

Abstract Neuroblastoma is the most frequent extra-cranial pediatric cancer with high-risk disease possessing a dismal five-year survival rate <50%. Antibody-based therapies targeting the surface disialoganglioside GD2 have shown promising anti-tumor activity in patients however efficacy is strongly hampered by immunosuppressive mechanisms present in the tumor microenvironment. Neuroblastomas typically feature low mutational burdens, limited major histocompatibility complex class I expression, increased immune checkpoint markers, sparse immune infiltration, and soluble mediators which drastically limit anti-tumor immunity. Given the emerging link between elevated copper levels and tumoral immune evasion, we explored copper chelation as a therapeutic strategy using the agents tetraethylenepentamine (TEPA) and the clinically approved analogue triethylenetetramine (TETA). Using the immunocompetent TH-MYCN model, we performed single-cell RNA sequencing supported by OPAL multiplex immunohistochemistry and cytokine profiling of resected tumors to assess cellular and molecular changes occurring after one week of TEPA treatment. Therapy was observed to successfully deplete intratumoral copper and reinvigorate anti-tumor immunity with increased infiltration and activity of pro-inflammatory immune cells, and was specifically found to induce egress and N1-polarisation of neutrophils. Further mechanistic studies in vitro revealed the sequestration of copper by neuroblastoma cells attenuated neutrophil function, which could be successfully reversed upon TEPA treatment. Findings propose a novel mechanism of immune evasion, highlighting copper chelation as a therapeutic strategy to counteract immunosuppression. Using the TH-MYCN model, TEPA was employed as a priming agent to effectively potentiate anti-GD2 antibody therapy and achieve durable tumor control. Importantly, this was associated with increased Fc-receptor-bearing natural killer and myeloid cells, which elicit tumor clearance via antibody-dependent cellular cytotoxicity. Currently indicated for the treatment of copper overload disorder Wilson’s disease, TETA was evaluated for potential repurposing as a novel immunomodulatory agent. Using the syngeneic NXS2 model, TETA exhibited an exceptional safety profile and combination therapy achieved durable tumor control with no relapses occurring after treatment cessation. This result was similarly associated with the infiltration of pro-inflammatory immune cells, including N1 neutrophils. Collectively, this study credentials copper chelation as a non-toxic strategy to disrupt the immunosuppressive tumor microenvironment and reinvigorate anti-tumour immunity. Findings provide crucial translational evidence for repurposing TETA to potentiate anti-GD2 antibody therapy and improve neuroblastoma patient responses. Citation Format: Jourdin R. Rouaen, Antonella Salerno, Fabio Luciani, Jayne Murray, Tyler Shai-Hee, Nicodemus Tedla, Michelle Haber, Toby N. Trahair, Orazio Vittorio. Copper chelation overcomes the immunosuppressive neuroblastoma microenvironment to potentiate anti-GD2 antibody therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2673.

Abstract 320: Development and automation of a streamlined targeted enrichment method for cancer mutation detection

Abstract Next Generation Sequencing (NGS) of DNA is a powerful tool for the detection of genetic variations, including single nucleotide polymorphisms, copy number variation, and small insertions/deletions. Target enrichment technologies enhance DNA sequencing by enabling users to analyze specific regions of interest only, which helps to effectively increase sequencing depth and sample throughput while minimizing cost. However, many targeted DNA library construction workflows are not optimal for routine genetic testing needs due to inconsistent, lengthy workflow. This poses significant challenge to application like cancer mutation profiling that requires detection sensitivity down to 1% or below due to heterogeneous nature of tumor tissue. In addition, high throughput testing with minimal hands on time is desirable with the rapid advance of precision medicine. Magnetic bead separations are commonly used between the individual reactions of targeted DNA library preparation workflows for cleanup and size selection. These bead clean up reactions are not only labor-intensive and tedious procedures but can also greatly contribute to sample-to sample variation especially when employing automated library preparation procedures. With the sophisticated QIAseq Targeted DNA Pro, we developed a novel streamlined targeted DNA workflow that greatly reduces handling variation by replacing the majority of bead clean up steps with enzymatic reactions, which now can be finished in as little as six hours. In combination with the newly developed QIAseq Normalizer kit, the protocol has been successfully implemented on the Hamilton NGS Star liquid handling platform resulting in up to 96 highly uniform, complex and ready-to-sequence libraries that can be effortless generated in one run. This complete automated solution saves researcher up to four hours of hands-on time. When using commercial reference samples, cancer mutations down to 1% were consistently detected with this automated workflow. The presented data demonstrate that this integrated and streamlined workflow does not only provide an automation friendly workflow but also allows to reliably identify low frequent cancer mutations. The applications presented here are for research use only. Not for use in diagnostic procedures. Citation Format: Zhong Wu, Michelle Baird, Cornelia Mechlen, Peter Hahn, Jonathan M. Shaffer. Development and automation of a streamlined targeted enrichment method for cancer mutation detection [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 320.

Abstract 3468: Emerging lessons from patient-reported hospital discharge experiences among hospitalized cancer patients with frequent emergency department use

Abstract Background: While teamwork is essential to providing high-quality patient-centered care, challenges in interprofessional collaboration and decision-making in the hospital settings are common, especially for cancer patients. The purpose of this study was to identify emerging themes related to hospital discharge experiences among patients hospitalized for cancer who became frequent emergency department (ED) users following their hospital discharge. Design & Methods: A cohort of cancer patients discharged from an academic health center in Montreal (Canada) between October 2014 and November 2016 was assembled. Frequent ED (FED) users were identified as patients who had a > 4 ED visits in the year following hospital discharge using health administrative claims from the provincial universal health care program. Qualitative analysis of telephone interviews conducted with patients 30 days’ post-discharge were used for in-depth exploratory analyses to characterize hospital discharge experiences and transition process from the hospital to the community. Results: A cohort of 1253 cancer patients was formed. The mean age was 70.9 (SD=11.8) and the most frequent cancers included 488 (38.9%) respiratory and 309 (24.6%) upper digestive cancer. Overall, 14.5% (n=182) of patients became FED users. Content analyses revealed the most common emerging themes from the FED patients interviews on hospital discharge experiences. These included:1. Early hospital discharge putting patients at high risk of being re-admitted and going back to the ER shortly after that. Some patients mentioned post-discharge complications and emerging of new health issues that could have been avoided if patient was kept in the hospital for longer.2. Lack of communication between different specialists at the hospital. Some patients mentioned the help of a nurse as crucial during inpatient stays in maintaining communication between doctors. 3. Lack of communication of medications prescribed. Some patients mentioned the lack of communication of what doses was modified, what medications were stopped and which ones were newly prescribed.4. The need to schedule follow-up appointments at the time of hospital discharge. This becomes especially important for vulnerable patients who have been on pain medication during the hospital stay, affecting their cognitive abilities and making post-discharge planning more difficult. Conclusions: This study using integrated data from administrative claims and patient interviews provided insights into the challenges related to hospital discharge experiences and transition into community among hospitalized cancer patients with frequent emergency department use. Application of our findings could assist in hospital discharge preparation and improvement in healthcare delivery and health outcomes. Citation Format: Siyana Kurteva, Robyn Tamblyn. Emerging lessons from patient-reported hospital discharge experiences among hospitalized cancer patients with frequent emergency department use [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3468.

Abstract 4344: Comprehensive analysis of LINE-1 transposable elements in colorectal cancer

Abstract Background: Colorectal cancer (CRC) is the third most frequent cancer worldwide, and approximately a third of patients die from the disease. There is therefore an urgent need to better understand CRC biology. A particular feature in (colorectal) cancer is the activation of LINE-1 (L1) retrotransposons: DNA fragments which propagate to other places in the genome through an RNA intermediate. Per genome, about 100-150 genomic L1 copies are still retrotransposition-competent, but repressed in most somatic tissues. Their role in tumor development is currently unknown. Recently, the PCAWG consortium characterized the landscape of somatic L1 retrotranspositions in a series of primary cancers of different origin, and identified 124 recurrently active L1 source regions. However, only a limited number of these concerned CRC. Aim: This study aims to perform a comprehensive analysis of L1 activity in a large cohort of metastatic colorectal cancer. Methods: To this end, we retrieved data from the Hartwig Medical Foundation, comprising deep (106x) whole genome sequencing (WGS) data from metastatic CRC (n=745), to compare to breast (n=888) and lung cancer samples (n=640). We determined L1 activity as the number of somatic L1 insertions reported by the HMF DNA analysis pipeline and used the activity of each of the 124 L1 sources as previously reported by the PCAWG consortium. Results: 99% of mCRC samples (n=741) displayed at least 1 somatic L1 retrotransposition, with at least 10 retrotranspositions in 89% of samples. L1 retrotransposition is more prevalent in mCRC than in metastatic lung and breast cancer, in which only 40% and 20% had at least 10 retrotranspositions per sample, respectively. Each cancer type showed a unique profile of active L1 sources. We did not observe a clear preference of L1 insertions for a single genomic region. However, in CRC, the gene most frequently affected in an exon was APC (n=13), an important tumor-suppressor gene. An analysis of somatic SNVs and SVs confirmed an association of mutations in some known L1 regulators such as TP53 with increased L1 activity, whereas mutations in others showed no change in the number of somatic retrotranspositions. Conclusions: We conclude that somatic L1 retrotranspositions are highly prevalent in metastatic colorectal cancer. Presence of L1 insertions in APC suggests retrotranspositions start very early in CRC development and prompts further investigation into earlier CRC stages. Citation Format: Renske de Wit, Soufyan Lakbir, Caterina Buranelli, Gerrit A. Meijer, Sanne Abeln, Remond J. Fijneman. Comprehensive analysis of LINE-1 transposable elements in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4344.

Abstract 4778: Development of self-amplifying RNA vaccines targeting prostate tissue-restricted and tumor-associated antigens

Abstract Prostate cancer is the most frequent cancer type in men, with increasing incidence at advanced age. As this cancer is frequently slow growing, opportunities for cancer interception exist, particularly among men with low-grade tumors who frequently undergo active surveillance. A well-tolerated vaccine intervention would be ideal for this population. Self-amplifying RNA (saRNA) vaccines built on a replication-deficient alphavirus backbone such as VEEV, offer several advantages for vaccine development. Sequences for relatively large antigens can be encoded and efficiently expressed, at low vaccine doses. Practical and efficient delivery of the saRNA is possible with advanced nanoparticles such as cationic inorganic lipid nanoparticles (LION). Among candidate antigens for a prostate cancer interception vaccine, we selected prostein (SLC45A3), a protein whose natural expression is restricted to the prostate gland and prostate cancer and ERG, a member of the ETS family of transcription factors frequently involved in chromosomal translocations in prostate cancer. We generated saRNA constructs with several design strategies and demonstrated that upon in vitro transfection, both antigens are expressed as assessed by mass spectrometry and Western blot analysis. This was achieved using commercial transfection reagents and LION. Prostein expression was particularly notable in that this eleven-transmembrane protein could be detected in HEK-293 cells using flow-cytometry and cell-surface staining. Nearly 50% of the cell population stained positively. Immunogenicity of the vaccines was tested in mice. Following formulation with LION particles i.m. injection and boosting, saRNAs coding for prostein elicited strong cellular immunity as demonstrated by IFN-γ ELISPOT analysis. Detailed analysis of intracellular cytokine expression indicated a strong CD8 response. saRNAs coding for ERG also showed antigen-specific ELISPOTs. Using commercially available recombinant ERG protein, an ELISA was developed and a strong humoral response to the ERG saRNA vaccine was demonstrated. The saRNA vaccines will be further credentialled with additional preclinical studies including cancer preventive efficacy studies in genetically engineered mouse models of prostate cancer. Citation Format: Robert H. Shoemaker, Jesse H. Erasmus, Peter Berglund, Jason D. Marshall, Yuri Koboziev, Bradley M. Beckman, Brian D. Cholewa, Steven G. Reed. Development of self-amplifying RNA vaccines targeting prostate tissue-restricted and tumor-associated antigens [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4778.

Early Results of a Screening Program for Skin Cancer in Liver Transplant Recipients: A Cohort Study.

(1) Background: Skin cancer is the most common cancer in transplant recipients. Timely and regular screening may reduce advanced disease. The study aimed to determine referral rates to screening, the incidence, and risk factors of skin cancer in a Danish liver transplant recipient cohort. (2) Methods: All first-time liver transplant recipients, >18 years old, attending outpatient care between January 2018 and December 2021 were included. The referral rates and incidence of skin cancer/preneoplastic lesions were calculated. Risk factors were assessed using Cox regression analyses. (3) Results: Of the 246 included recipients, 219 (89.0%) were referred to screening, and 102 skin cancer/preneoplastic lesions were diagnosed in 32 (15.6%) recipients. The IR of any skin cancer/preneoplastic lesion was 103.2 per 1000 person-years. BCC was the most frequent skin cancer followed by SCC, IR: 51.3 vs. 27.1 per 1000 person-years, respectively. No cases of MM were observed. The IR of actinic keratosis and Bowen's Disease were 48.1 vs. 13.2 per 1000 person-years, respectively. Time since transplantation was independently associated with skin cancer/preneoplastic lesions, HR (95%CI) 2.81 (1.64-4.80). (4) Conclusions: The study determined the incidence and risk factors of skin cancer/preneoplastic lesions in liver transplant recipients enrolled in a screening program, while demonstrating a high screening referral rate.

Diagnostic Performance between Colposcopy Findings and Histopathology Reports

Background: Cervical cancer is the most frequent cancer in women worldwide. With appropriate screening, the condition can be prevented and treated. Colposcopy is a useful tool in the diagnosis and management of precancerous cervical lesions following primary screening. The gold standard for identifying precancerous lesions is histopathology. Objective: The aim of this study is to evaluate the diagnostic performance between colposcopy findings and histopathology reports Methods: The cross-sectional observational study was conducted in the Department of Colposcopy Clinic of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, from July 2022 to June 2023. A total of 62 subjects were included in the study. The questionnaire was pretested, corrected and finalized. Data were collected by face-to-face interview and analyzed by appropriate computer based programmed software Statistical Package for the Social Sciences (SPSS), version 24. Results: In this study, the mean age was found to be 36.8±11.9 years, with a range from 20 to >51 years maximum 44 (71.0%) of the patients were within the age group of 20 - 40 years. The majority 37 (59.7%) of patients completed SSC and most of the patients 56 (90.3%) were housewives. Most of the patients 59 (95.2%) were Muslims and about 32 (51.6%) came from middle-income families. About 25 (40.3%) patients were married between the ages of 15-17 years. About 25 (40.3%) were between 16-18 years during their first delivery and about 26 (41.9%) had 3-4 children and 21 (33.9%) had more than 4 children. Most of the patients 43(69.4%) had history of received OCP. Regarding colposcopic diagnosis, 12.9% (n=8) were normal, 69.4% (n=43) were CIN I, 9.7% (n=6) were CIN II and 8.1% (n=5) were CIN III and 30.6% (n=19) chronic cervicitis, 46.8% (n=29) CIN I, 6.5% (n=4) CIN II, 6.5% (n=4) CIN III, 4.8% (n=3) carcinoma in situ and 4.8% (n=3) were invasive squamous cell carcinoma by the histopathological diagnosis. Conclusion: Colposcopy had a rather high diagnostic accuracy for histopathologically verified precancerous cervical lesions. Even if the results of the screening tests are normal, patients who report with postcoital and postmenopausal bleeding should have colposcopies and biopsies. Colposcopy also has a high sensitivity, therefore it is simple to use the "see and treat" approach to lower dropout rates.

Exploring the barriers to Pap smear test compliance: A qualitative study for improving cervical cancer screening in the primary health care.

Cervical cancer in Iran ranks as the fourth most frequent cancer among women. Pap smear (PS) is the best standard for detecting cervical cancer, but many people, even healthcare providers (HCPs), do not maintain it. HCPs play a critical role in promoting PS uptake. The purpose of the study was to explore barriers to cervical cancer PS screening compliance from the HCPs' perspective. The present qualitative content analysis was conducted through semi-structured in-depth interviews. A total of 28 HCPs were interviewed between July and August 2020. A diverse sample of HCPs was selected using purposive sampling. Data analysis was based on the five steps proposed by Graneheim and Lundman. MAXQDA (2020) was used for data analyzing. Ten key sub-categories were identified and organized into three categories: individual, environmental, and socio-cultural factors. The sub-categories included inadequate risk perception, inappropriate attitude, low commitment, emotional factors, low priority over health, requirements and consequences of the test, deficiencies of health centers, organizational factors, traditions and religious believes. HCPs face multiple barriers for PS. Exploring and decreasing barriers of PS in HCPs may increase compliance in them and their clients because they play an influential role in instructing and persuading women to take the PS. There is need to explore these barriers and identify possible interventions to change them. Insights from this study are useful for developing policies around national PS programs, too.

Women’s experiences with breast cancer during diagnosis and therapy, Wolaita, Ethiopia: a qualitative study

BackgroundBreast cancer is the most common cancer in women and the most frequent cancer worldwide. After being diagnosed with breast cancer, women experience unexpected and stressful events. In Ethiopia, specifically in the study area, the experiences of women with breast cancer, the challenges they face during treatment and follow-up have not been thoroughly investigated.ObjectiveThis qualitative study explores the experiences of women diagnosed with breast cancer and undergoing therapy at a University-based hospital in Ethiopia.MethodsA qualitative research design was used, to explore the experiences of women diagnosed with breast cancer and undergoing therapy. A purposively selected sample of ten women who had been diagnosed with breast cancer and were receiving therapy was recruited. Recruitment was conducted from August 1 to September 30, 2022. Semi-structured face-to-face interviews were conducted to collect data on their experiences. The interviews were transcribed verbatim, and a thematic analysis approach was employed utilizing open coding. The coded data were then analysed to reveal important insights and understandings about the participants’ experiences with breast cancer during the diagnosis and therapy journey.ResultThe thematic analysis of the data revealed four prominent themes: women’s mixed emotions, characterized by a sense of high threat and hope upon receiving breast cancer diagnosis results; dealing with the changes, both physical and psychological, that the cancer and its treatment bring about in women’s bodies and emotional well-being; dealing with the challenges associated with accessing therapy, including unfavourable hospital conditions and financial hardship; and experiencing care and supports from health care providers, family and friends, and faith-based communities.ConclusionThese findings underscore the importance of providing comprehensive support and care for women with breast cancer. Enhancing the hospital environment, addressing resource shortages, and prioritising patient well-being are crucial steps towards improving the experiences of breast cancer patients in the study area.

Awareness of lung cancer risk factors and symptoms in Syria: an online cross-sectional study

Background Globally, lung cancer is the leading cause of cancer fatalities and the second most frequent cancer. Population knowledge of the features of lung cancer is a crucial strategy for early diagnosis and decreasing the mortality rate of lung cancer patients. In this study, we aim to assess the Syrian population’s knowledge of lung cancer and its risk factors and to measure awareness of symptoms related to lung cancer. Methods This national cross-sectional study was conducted between October 12 to November 21, 2022, in Syria. We included Syrian people above 18 years from all Syrian governorates. The questionnaire consisted of three categories of questions: sociodemographic information, awareness of lung cancer symptoms, and awareness of lung cancer risk factors. Results Overall, 2251 participants were involved in this research; almost half of them (47.3%) were aged between 21-30 years, and 30.9% indicated they are smoking cigarettes. The overall mean score of knowledge regarding closed questions about risk factors of lung cancer was 4.29; however, the mean score of knowledge regarding open questions about symptoms of lung cancer was 1.52. About half of the study sample (51.3%) indicated that unexplained weight loss is a possible symptom of lung cancer. Our findings showed that cigarette smokers have a lower probability of having adequate knowledge toward lung cancer risk factors than a non-smoker (AOR=0.73, COR=0.68, P-value<0.05). We also defined that females have higher statistically significant odds (AOR=1.3, COR=1.38, P-value<0.05) for being knowledgeable about the symptoms of lung cancer compared to the male sample study. Conclusion According to our findings, there is inadequate knowledge toward lung cancer risk factors and moderate knowledge of lung cancer symptoms. Along with educational programs to raise public knowledge of the dangers of smoking and other LC risk factors, effective tobacco control policy execution is crucial.

The correlation between interleukin-4 (IL-4) and programmed cell death-ligand 2 (PD-L2) expression with clinicopathological characteristics on prostate cancer

Prostate cancer (PCa) is the most frequent cancer diagnosed worldwide and the second most common malignancy in men. IL-4 is one of cytokines related to the inflammation process. An increase level of IL-4 in patients with PCa might be related to progression to castrate-resistance prostate cancer. Programmedcell death-ligand 2 (PD-L2) plays an important role in the anti-tumor immune system, however the exact mechanism is not fully understood. This study aimed to investigate the correlation between IL-4 and PD-L2 expression with the clinicopathological characteristic of PCa. The IL-4 and PD-L2 examinations wereperformed using quantitative real-time polymerase chain reaction (qRT-PCR) while clinicopathological characteristics were described by the Gleason score and International Society of Urological Pathology (ISUP) grade. Data collected were then analyzed using Pearson and Spearman test. In total, 20 patients withPCa tissue were collected between 2015 and 2020. The mean level of IL-4 and PDL2 were higher in metastatic PCa/M-PCa (105.64 and 665.42 ng/mL) compared to non-metastatic PCa/NM-PCa (41.62 and 215.06 ng/mL). A significant difference with medium correlation between IL-4 and PD-L2 with Gleason score and ISUPgrade was observed on all samples (p = 0.035 and 0.045; r = 0.454 and 0.473). However, no significant difference with weak correlation was observed on each group (p = 0.136 and 0.858; r = 0.065 and 0.506). Interestingly, there was a significant difference with very strong correlation observed between IL-4 andPD-L2, both on all samples (p = 0.001; r = 0.955) and on each group (p = 0.001 and 0.001; r = 0.917 and 0.955). In conclusion, there is a correlation between IL-4 and PD-L2 with the clinicopathological characteristics of PCa.

Potential bioactive compound and hub gene identification of endometrial carcinoma using systems biology

Endometrial carcinoma is a frequent cancer of the female genital tract. Endometrial carcinoma accounts for 97% of all uterine malignancies and 3 % of sarcomas that develop from the endometrium’s glands. Endometrial cancer is frequently found in its early stages since most women quickly report postmenopausal vaginal hemorrhage. The need for more advanced medications to improve survival in such situations is still unfulfilled. As a result, there is growing interest in employing an herbal treatment to treat endometriosis, which seems to be an effective strategy. We have discovered a few unintended targets (ligands) in our investigation that are active components of common therapeutic herbs. The differentially expressed genes (DEG - target protein) for endometrial cancer were found using the NCBI and CIViC databases. In our investigation, the protein used for docking and simulation was PDB ID: 3THW. Using the Cytoscape server, the gene-encoding protein network has been identified. It was discovered that the Protein 3THW's binding energy to the bioactive substance (Asarone) was −7.15 Kcal/mol. It was discovered that the crucial interacting amino acid residues were ILE648, PHE650, ILE651, VAL802, TYR815, VAL817. The properties of the pharmaceutical target are further investigated by employing a molecular simulation study for 100 ns with NAMD software. Low RMSD and SASA (Solvent accessible surface area), high RMSF, High hydrogen bonds, between Asarone and MSH2 demonstrated their potency as endometrial cancer inhibitor compounds. Based on these analyses we infer that the bioactive substances originating from medicinal plants may be an effective treatment for endometrial cancer. Communicated by Ramaswamy H. Sarma

Aggressiveness in systemic anticancer therapy at the end of life in an oncology center.

An increasing aggressiveness in cancer treatment at the end of life (EoL) has been reported in several, but not all, countries. This study aimed to see how aggressive cancer treatment is at the EoL in an oncology center. Retrospective study of patients 18 years or older with a solid cancer diagnosis who died in 2017. The focus was systemic anticancer therapy (SACT), excluding hormonotherapy. In 2017, 2024 patients with solid tumors died. Of those patients, 1262 (62%) were male, and the median age was 69 (range 19-97) years. The most frequent primary cancer was lung cancer, followed by colorectal and stomach cancers, and 740 (37%) patients had metastatic disease. The median interval between SACT and death was 61 days. Of the patients undergoing SACT, 216 (27%) did it in the last month of life, 174 (22%) between 8 and 30 days from death, and 42 (5%) in the last week. On multivariable analysis, head and neck, colorectal, breast, and melanoma primaries; age group (older than 65 years); and metastatic disease had statistical significance associated with SACT. Of these variables, only metastatic disease is more likely to undergo SACT. This study confirms the relatively frequent aggressiveness in cancer treatment at the EoL. Taking into consideration previously published data, it can be tentatively concluded that the use of SACT increased in the last month and the last week of life.