bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4767: Changes in the NSE and S100B levels following treatment with peripheral neuropathy-inducing drugs
Authors: Vontikommu Priya R. , Selvakumar Shriya , Natarajan Umamaheshwari , Rathinavelu Appu
Published: March 2024

Neo-adjuvant chemotherapy is considered the standard of care for patients with multiple myeloma (MM). Peripheral neuropathy (PN) is one of the most common chemotherapy-induced side effects that impact 50% of all patients who receive chemotherapy and can lead to discontinuation of drug treatment. Treatment with Bortezomib (BTZ), Cisplatin (CIS), and Vincristine (VIN) has been established as the most common trigger of Chemotherapylnduced Peripheral Neuropathy (CIPN) among cancer patients. Since CIPN can lead to disabling long-term adverse effects, many cancer patients discontinue or limit their treatment regimen once they see signs or symptoms of CIPN. Therefore, it was hypothesized that developing diagnostic/prognostic biomarkers that can accurately predict the onset or progression of CIPN would help to determine the chemotherapy eligibility with the above-mentioned drugs and proactively prepare for protective care. Hence, our initial goal was to elucidate the molecular mechanisms underlying the onset and progression of CIPN that would allow for the identification of suitable biomarkers that can be used for monitoring before or during chemotherapy with BTZ, CIS, and VIN. Initially, we conducted in vitro studies to identify the underlying molecular mechanisms activating CIPN related pathways. We used neuronal Schwann cells (RT4), for testing the neurotoxic effects of BTZ, CIS, and VIN that might precede or coincide with the onset of CIPN in an in vivo condition. Interestingly, the BTZ treatment was able to significantly reduce the intracellular level of NSE and S100B in RT4 cells compared to the untreated controls, when they were measured using an immunofluorescence assay and Western blot. Furthermore, we conducted an in vivo study to determine the CIPN using rats. We used the sciatic nerve (SN) from drug-treated animals to check the S100B level using the ELISA method. Our preliminary results showed that levels of S100B in the SN of Rats were reduced following 8 weeks of treatment with the PN-inducing chemo drugs. We anticipate that this study will enrich our understanding of how chemotherapy medications induce PN in cancer patients and guide us to identify reliable biomarkers (This project was supported by the PFRDG grant of the Nova Southeastern University, Ft. Lauderdale Florida, and the Royal Dames of Cancer Research Inc., Ft. Lauderdale, Florida).

Citation Format: Priya R. Vontikommu, Shriya Selvakumar, Umamaheshwari Natarajan, Appu Rathinavelu. Changes in the NSE and S100B levels following treatment with peripheral neuropathy-inducing drugs [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 4767.
Abstract 4786: Colorectal cancer screening rates among deaf, deafblind, and hard of hearing adults aged 45 to 75 years old
Authors: Wang Regina M. , Rao Sowmya R. , Bergeron Erika J. , Perrodin-Njoku Emmanuel C. , Kushalnagar Poorna
Published: March 2024

Background: Deaf, deafblind, and hard of hearing (DDBHH) individuals who use American Sign Language (ASL), a subpopulation of the disability, experience disparities concerning cancer screening and cancer-related health outcomes. For this study, we explored colorectal cancer screening rates among DDBHH survey respondents in comparison to rates found in the hearing population.

Materials and Methods: Using the National Cancer Institute Health Information National Trends Survey in ASL (Kushalnagar et al., 2015), we surveyed participants 18+ years old using the Center for Deaf Health Equity at Gallaudet University’s database of over 2,500 DDBHH participants from all over the USA, including Hawaii and Puerto Rico. We used the U.S. Preventive Services Task Force (USPSTF) guidelines’ age cutoffs to assess adherence to colorectal cancer screenings.

Results: Survey response rate within three weeks of mail out in July 2023 was 12%. A total of 405 DDBHH adult participants answered screening questions for colorectal cancer in ASL and English. Overall, 43.7% self-reported screening adherence for age-eligible (45-75 years) colorectal cancer screening; 54.7% reported never having a colorectal cancer screening. Similarly-aged hearing adults reported 58.7% adherence in the English version of the National Health Interview Survey (NHIS).

Discussion: With the 43.7% adherence rate, the DDBHH community is lagging behind colorectal cancer screenings compared to the general population of hearing adults. Estimating the colorectal cancer screening rates among the DBHH community and understanding the reasons for these existing disparities is important to achieve screening adherence of 68.3%, the target set by the Healthy People 2030. Such research will aid the Center for Deaf Health Equity to actively work with the community to improve strategies to increase colorectal cancer screening.

Citation Format: Regina M. Wang, Sowmya R. Rao, Erika J. Bergeron, Emmanuel C. Perrodin-Njoku, Poorna Kushalnagar. Colorectal cancer screening rates among deaf, deafblind, and hard of hearing adults aged 45 to 75 years old [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 4786.
Abstract 4808: Small intestinal leiomyosarcoma in a young adult
Authors: Guo Alyssa A. , Bentley Blake H. , Ellington Abigail L. , Lu Haiyan , Lippert William C.
Published: March 2024

Objectives: • Outline the epidemiology of leiomyosarcoma•Identify the immunohistochemistry of a leiomyosarcoma

Introduction: Primary small intestinal malignancies are rare malignancies as compared with other malignancies of the gastrointestinal tract. Here, we present a case of a jejunal leiomyosarcoma in a young adult.

Case Presentation: A 23-year-old Caucasian male with GERD presented with five months of abdominal pain, intermittent nausea with non-bloody emesis, and a 20-pound weight loss. Presenting vital signs were within normal limits. Physical exam revealed conjunctival pallor with epigastric tenderness to palpation. Serology demonstrated iron deficiency anemia, hemoccult positive stool, negative CEA, CA19-9, and AFP tumor markers. HIV antigen antibody and EBV-PCR were non-reactive. CT of the abdomen and pelvis revealed markedly thickened heterogenous jejunal loop in the left hemiabdomen with associated mesenteric adenopathy and small volume pelvic ascites. EGD with push enteroscopy revealed a single, malignant appearing and ulcerated mass in the proximal jejunum. PET-CT showed a hypermetabolic, multilobulated, ill-defined mass involving multiple loops of jejunum. He underwent exploratory laparotomy with resection of a proximal jejunal mass (10x8 x7 cm), mesenteric lymphadenectomy, and a jejunojejunostomy creation. Pathology demonstrated leiomyosarcoma (pT2aN0MoG3), and he was initiated on cyclophosphamide and doxorubicin.

Discussion: Primary small intestinal malignancies are rare malignancies with an incidence of less than 5% of all GI malignancies. 56 cases of GI leiomyosarcoma in adults were identified between 2000-2012 with a peak incidence between 55-59 years of age (Aggarrwal 2012). Leiomyosarcomas are soft tissue sarcomas arising from bones, tendons, blood vessels, or muscles with a spectrum of disease ranging from low-grade cutaneous lesions to aggressive lesions of internal organs with significant potential for metastasis (Pipe 2002). Diagnosis is based on immunohistochemical positivity for SMA, desmin, and h-caldesmon, and negativity for CD117, CD34, and DOG1.1, notably lacking KIT and PDGFRA mutations (Aggarwal 2012). Treatment involves surgical resection and a cost benefit analysis of adjuvant chemotherapy with (Reynolds, 2014). This case of a 23 year old, without significant risk factors, diagnosed with a jejunal leiomyosarcoma presents as one of the youngest cases ever to be reported and emphasizes the importance of recognizing the cancer in a broader range of the adult population.

Citation Format: Alyssa A. Guo, Blake H. Bentley, Abigail L. Ellington, Haiyan Lu, William C. Lippert. Small intestinal leiomyosarcoma in a young adult [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 4808.
Abstract 4816: Racial disparities in adjunctive supportive care medication use in pancreatic cancer patients
Authors: Kweyete Olga M. Trejos , Guo Yi , Rogers Sherise C. , Scarton Lisa , DeRemer David L. , Whitner Chardae L. , Wilkie Diana J. , Allen John M.
Published: March 2024

Background: Beyond its well-known lethality, pancreatic cancer (PC) is associated with a wide variety of physical and psychological complications. These complications collectively lead to an increase in symptom burden experienced by patients with PC, as compared to other cancer types, leading to lower health-related quality of life (HRQoL) and worsened clinical outcomes. Reducing symptom burden is often achieved through the use of supportive care medications (SCM). Racial disparities have been described in the use of pain and psychiatric medications but limited research has explored potential disparities in access to and utilization of other SCM among diverse racial and ethnic groups. The goal of this study was to illustrate the presence of racial/ethnic disparities in the treatment patterns of supportive care medications in end-of-life care of PC patients

Methods: We used data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database from 2005 to 2017. Participants were identified using ICD9 and ICD10 diagnostic codes. Patients diagnosed with PC and have died in 2005-2007 with more than 1 year of Medicare enrollment before death were included. Logistic regression models to assess the association between use of supportive care medications and race, adjusting for covariates (sex, race, age, marital status, education, income, residence, CCI, year of diagnosis of PC, cancer stage).

Results: After the application of the inclusion/exclusion criteria, 74,309 patients were included in the final analysis (White: 72.53%, Black 11.01%, Hispanic 9.60%, Asian/Pacific Islander 6.58%) Racial and ethnic disparities in the use of multiple SCM drug classes were identified. The results are summarized in Table 1.

Conclusion: Disparities in the use of SCM were found in patients with PC. Minorities had significantly less use of sleep aids and headache aids, and increased use of cognitive aids and appetite stimulants. AAs also had lower uses of anti-emetics.

AA Hispanic Asian SCM Drug Class aOR 95% CI aOR 95% CI aOR 95% CI Anti-emetics 0.77 (0.73, 0.81) 0.98 (0.93, 1.03) 1.01 (0.95, 1.08) Appetite stimulants 1.06 (1.01, 1.11) 1.01 (0.96, 1.06) 1.28 (1.20, 1.36) Cognitive aids 1.38 (1.25, 1.53) 1.04 (0.93, 1.17) 1.11 (0.97, 1.26) Headache aids 0.68 (0.63, 0.74) 0.81 (0.74, 0.87) 0.85 (0.77, 0.93) Sleep aids 0.71 (0.67, 0.75) 0.87 (0.82, 0.92) 0.87 (0.81, 0.93)

Citation Format: Olga M. Trejos Kweyete, Yi Guo, Sherise C. Rogers, Lisa Scarton, David L. DeRemer, Chardae L. Whitner, Diana J. Wilkie, John M. Allen. Racial disparities in adjunctive supportive care medication use in pancreatic cancer patients [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 4816.
Abstract 488: Modulation of ENPP1 activity and 2'3'-cGAMP degradation in ovarian cancer cell lines via loadable pre-formed lipid nanoparticles
Authors: Taylor David , Ji Jiajia , Rzeczycki Phillip , Collins Margaret L. , Clements Lauren , Ariosa Aileen R.
Published: March 2024

Ovarian cancer is a complex heterogeneous disease with various subtypes and diverse molecular mechanisms of pathogenesis. Among different forms, epithelial ovarian cancer is the most common, representing up to 90% of total reported cases. Due to the lack of early diagnostic tools, the prognosis is mainly poor, as most cases are typically identified in advanced stages. Thus, a more thorough understanding of the inherent complexities of the disease, in terms of its biochemical etiology, will allow for identification of specific molecular and genetic profiles that could lead to more effective treatment plans. Recent studies have shown that ENPP1 may play a role in cancer cell proliferation, migration, and invasion in ovarian and other types of cancer. ENPP1 is a glycosylated type II transmembrane protein acting as a pyrophosphatase and phosphodiesterase with broad specificity. ENPP1 substrates include mononucleotides and cyclic dinucleotides such as the second messenger, 2'3'-cGAMP, which binds to and activates STING. 2'3'-cGAMP is exported extracellularly by cancerous cells into the tumor microenvironment where uptake into neighboring cells can activate their STING-dependent type 1 interferon pathway and promote antitumoral immune responses. ENPP1 can hydrolyze extracellular 2'3'-cGAMP however, allowing cancer cells to evade such an immune response. In this study, we assessed the activity of ENPP1 in CaOV-3, SK-OV-3, and PA-1 ovarian cancer cell lines using a fluorometric cell-based assay. The effects of ENPP1 inhibition via a chemical inhibitor on extracellular 2'3'-cGAMP levels were characterized and compared with siRNA-mediated knockdown of ENPP1 via loadable pre-formed lipid nanoparticles, which enable small-scale encapsulation and transfection of nucleic acid cargo. In addition, we explored whether uptake of exogenous 2'3'-cGAMP into THP-1 and RAW immune cell lines can be enhanced through delivery via preformed loadable lipid nanoparticles. Corresponding immune cell activation was also assessed using immunoblotting and RT-PCR. Our results demonstrate how modulation of ENPP1 activity and 2'3'-cGAMP levels in ovarian cancer cell lines using unconventional, pre-formed loadable lipid nanoparticle transfection reagent can aid in elucidating mechanisms of immune evasion in cancer cells.

Citation Format: David Taylor, Jiajia Ji, Phillip Rzeczycki, Margaret L. Collins, Lauren Clements, Aileen R. Ariosa. Modulation of ENPP1 activity and 2'3'-cGAMP degradation in ovarian cancer cell lines via loadable pre-formed lipid nanoparticles [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 488.
Abstract 4955: An analytic pipeline of neoantigen selection for both MHC-I and MHC-II pathways
Authors: Lee Ko-Han , Sears Timothy , Castro Andrea , Zanetti Maurizio , Carter Hannah
Published: March 2024

Background: Accurate neoantigen selection is pivotal for assessing mutation burden and optimizing cancer vaccine formulation thereby playing a crucial role in cancer immunotherapy. The concurrent activation of CD4+ and CD8+ T cells engenders a robust immune response, which is key to effective treatment. However, currently analytic tools predominantly focus on the MHC-I pathway, typically relying on metrics such as gene expression level and MHC-binding affinity of mutated peptides. To address this gap, our study presents a comprehensive pipeline that encompasses both MHC-I and MHC-II pathways and integrates three critical dimensions of immune response: neoantigen abundance, presentation, and immunogenicity.

Methods: We estimated mutated peptide abundance by analyzing genomic allelic frequency, transcriptomic allelic frequency, and RNA expression level. Antigen presentation was assessed using the patient harmonic binding rank (PHBR, a composite binding score for all potential MHC-peptide pairs) and MHC diversity (the variety of MHC alleles involved in peptide binding), with additional consideration for the loss of heterozygosity of MHC-I alleles, potentially indicative of immune escape. For immunogenicity, we factored in agretopicity (comparison of MHC-binding affinity between mutated and wild-type peptides), foreignness (similarity to immunogenic foreign antigens), and dissimilarity (sequence disparity with self-peptides, reflecting T cell negative selection process).

Results: Implementing our pipeline on a dataset from Parkhurst et al. (2019), we analyzed immune reactivity in relation to 11,537 somatic mutations from 75 gastrointestinal cancer patients. Key metrics—RNA expression, transcriptomic allelic frequencies, PHBR, and MHC diversity—demonstrated significant correlations with both CD4+ and CD8+ activity (p<0.05). Notably, genomic allelic frequency was a significant factor in CD8+ reactivity, whereas agretopicity was crucial for CD4+ reactivity.

Conclusion: Our pipeline elucidates the necessity for implementing both MHC-I and MHC-II pathway analyses to effectively select neoantigen candidates for CD8+ and CD4+ T cells respectively. The study confirms that abundance and antigen presentation metrics are robust indicators of neoantigen immunogenicity, supporting their use as potential markers in crafting more effective cancer vaccines. The findings highlight the critical role of this dual-pathway selection approach in generating a comprehensive immune response through neoantigen vaccination.

Citation Format: Ko-Han Lee, Timothy Sears, Andrea Castro, Maurizio Zanetti, Hannah Carter. An analytic pipeline of neoantigen selection for both MHC-I and MHC-II pathways [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 4955.
Abstract 4991: Radiotherapy-induced immunological and therapeutic response depends on stem-like TCF-1+PD-1+CD8+ T-cells
Authors: Köksal Hakan , Herbst Michael , Marti Nicola , Broek Maries van den
Published: March 2024

Radiotherapy is a frequently used treatment for cancer. Recent data, including ours, showed that radiotherapy promotes an inflammatory response in the tumor that supports tumor-specific immunity, and in fact, the efficacy of radiotherapy in pre-clinical models depends on CD8+ T-cells. According to our preliminary data, the response to radiotherapy is independent of de novo recruited CD8+ T-cells, suggesting that radiation drives differentiation and proliferation of preexisting intratumoral CD8+ T-cells. Intratumoral CD8+ T-cells are heterogeneous concerning phenotype and function. Under conditions of chronic stimulation by antigen, a subset of CD8+ T-cells expressing PD-1 and the transcription factor TCF-1 was described. These so-called stem-like CD8+ T-cells, which give rise to effector cells, were shown to be essential for the clinical response to PD-1 blockade. How radiotherapy influences the different CD8+ T-cell subsets in the tumor microenvironment has not been comprehensively investigated. We propose that the efficacy of radiotherapy depends on the presence of stem-like CD8+ T-cells, presumably by giving rise to effector cells. To address this, we selectively depleted TCF-1+ cells from tumor-bearing mice immediately before radiotherapy. Subsequently, we correlated tumor regression with the immunological response using single-cell analyses of intratumoral CD8+ T-cells. In the absence of TCF-1+ cells, we found a reduced efficacy and reduced number of intratumoral effector cells after radiotherapy. We currently analyze our single-cell RNA-sequencing data and expect to discover novel radiotherapy-induced pathways in CD8+ T-cells that contribute to therapeutic efficacy.

Citation Format: Hakan Köksal, Michael Herbst, Nicola Marti, Maries van den Broek. Radiotherapy-induced immunological and therapeutic response depends on stem-like TCF-1+PD-1+CD8+ T-cells [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 4991.
Abstract 4998: Pralsetinib induces opportunistic infection in RET fusion-positive NSCLC patients via inhibition of IL-2 production by blocking Jak3-Stat5 activation
Authors: Yoon Shinkyo , Ryu Hyun-Min , Kim Sang-We , Park Kang-Seo , Lee Dae Ho
Published: March 2024

Background: Oncogenic alteration in RET, representing 1-2% of non-small cell lung cancer (NSCLC), is one of the important targets. Pralsetinib is a selective RET inhibitor that targets RET fusions. We present a case series on opportunistic infections and the mechanism of immunosuppression.

Methods: From October 2021 to March 2022, we administered pralsetinib to a total of 15 patients with NSCLC harboring RET fusion. We retrospectively analyzed the clinical efficacy and adverse event related to pralsetinib. To investigate the potential impact of pralsetinib on T-cells, we examined cytokine release from Jurkat T (JT) cells after pralsetinib treatment. To test if Stat5 bind to IL-2 promotor, we conducted Chromatin Immunoprecipitation (ChIP).

Results: Out of a total of 18 patients with measurable disease, 14 patients (93%) achieved a partial response. With the median follow-up duration of 8.7 months, four cases of opportunistic infections were occurred. Notably, three patients (16.6%) experienced invasive pulmonary aspergillosis, and one patient (5.5%) experienced cytomegalovirus pneumonia. To mimic conditions akin to activated T cells, we treated JT cells with PMA and ionomycin, inducing IL-2 release through the binding of NFAT, AP-1, and NF-κB to the IL-2 promoter. Following approximately two weeks of pralsetinib treatment, a decrease of IL-2 releases, the inhibition of Jak3 and the reduced-expression of JunB and c-Jun was observed. Additionally, to investigate the direct correlation between Jak3 and IL-2 release, JT cells were treated with ritlecitinib, the Jak3-selective inhibitor, for approximately two weeks. Like pralsetinib, a reduction in IL-2 release was observed. Furthermore, based on the evidence that Stat5 inhibition leads to reduced IL-2 release, we also showed that the transcription factor Stat5, a direct downstream signaling component of Jak3, binds to the IL-2 promoter during the activation of Jurkat T cells.

Conclusion: Pralsetinib inhibits additional IL-2 production by blocking Jak3/Stat5 activation triggered by IL-2 released during early T cell activation. As a result, the Jak3 inhibition induced by pralsetinib leads to a decrease in JunB/c-Jun expression and blocking Stat5 activation by reducing IL-2 release. Consequently, Pralsetinib-related opportunistic infections may be caused by inhibition of the JAK3 pathway and IL-2 release.

Citation Format: Shinkyo Yoon, Hyun-Min Ryu, Sang-We Kim, Kang-Seo Park, Dae Ho Lee. Pralsetinib induces opportunistic infection in RET fusion-positive NSCLC patients via inhibition of IL-2 production by blocking Jak3-Stat5 activation [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 4998.
Abstract 5039: Preanalytical workflow enabling cfDNA analysis from urine samples
Authors: Mancarella Daniela , Rutsch Julia , Erkelenz Lisa , Meyer Moritz , Witthaus Laura Sofie , Rath Moritz , Voss Thorsten
Published: March 2024

Introduction: Urine has become an important source of information in the liquid biopsy field. In contrast to blood, specifications for the collection, storage, transport and processing of urine intended for molecular examination are not widely established. Preanalytical specifications were published for urine cell-free DNA (cfDNA) only recently (CEN/TS 17811:2022). In this study, we investigated post-collection changes to cfDNA profiles in urine samples and present the performance of an optimized preanalytical workflow for cfDNA analysis.

Methods: Urine from apparently healthy, consented female individuals was spiked with processed cell-free male urine or with a cfDNA standard containing PIK3CA mutations (SensID). The urine was stabilized with a urine collection/stabilization solution under development at PreAnalytiX or was left unstabilized. Urine samples were stored for varying durations at different temperatures in a time course experiment to simulate different urine storage conditions. After storage, urine samples were centrifuged to remove cells and cfDNA was isolated from the supernatant via the QIAsymphony® platform (QIAGEN). Autosomal and male-specific targets were quantified using the Rotor-Gene® Q instrument and the therascreen® PIK3CA qPCR Kit (both QIAGEN) or the QIAcuity® Digital PCR System and a dPCR LNA PIK3CA Mutation Assay (both QIAGEN). Fragment size distribution was determined by TapeStation® Cell-free DNA ScreenTape® (Agilent Technologies).

Results: Analysis of cfDNA profiles in unstabilized urine stored for varying durations and temperatures highlighted changes which create artificial cfDNA profiles. The yield of cfDNA drastically decreased over time. Furthermore, the size distribution of cfDNA isolated from unstabilized urine was impacted by release of gDNA as well as DNA degradation. Urine stabilization minimized cfDNA degradation and gDNA release and allowed isolation of cfDNA that was analyzed with qPCR and dPCR even after urine storage. Analysis of isolated cfDNA revealed positive detection of PIK3CA mutations in spiked urine samples.

Conclusions: Changes in post-collection cfDNA profile can hinder downstream analysis, resulting in artificial or failed outcomes. Urine stabilization with a collection/stabilization solution under development at PreAnalytiX minimized DNA degradation and gDNA release. It enabled urine storage, allowed analysis of urine cfDNA and target detection by qPCR and dPCR.

Citation Format: Daniela Mancarella, Julia Rutsch, Lisa Erkelenz, Moritz Meyer, Laura Sofie Witthaus, Moritz Rath, Thorsten Voss. Preanalytical workflow enabling cfDNA analysis from urine samples [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 5039.
Abstract 5048: NF2 mutations are enriched in FH deficient renal cell cancer
Authors: Satter Khaled Bin , Xi Liqian , Rickets Christopher , Linehan William M. , Merino Maria J.
Published: March 2024

Introduction: NF2 is a tumor suppressor gene in charge of producing a protein called Merlin that controls cell growth and division. Mutations in the NF2 gene affect predominantly the nervous system causing the development of benign tumors. NF2 mutations have been reported in Renal cancers with morphologically specific tumor types and in aggressive tumors. We studied a cohort of 16 cases of RCC in which the NF2 mutation was identified and describe other molecular changes as well as morphology and clinic-pathological correlation.

Materials and Methods: Sixteen patients had been consented and treated for renal masses in protocols of the UOB division of the NCI. Next generation sequencing was performed with tumor DNA from FFPE tissue using the Illumina TruSight Oncology 500 Kit (TSO500) NextSeq 550DX. TSO500 assay was designed to detect single nucleotide variations, small insertions/deletions, copy number variations from 92 genes, TMB and MSI. Morphology and IHC stains were performed.

Results: Nine patients were female and 7 males, ranging in age from 21 to 87 years. Fourteen patients underwent partial or total nephrectomies, one case had a biopsy and in 1 case a metastatic tumor to a lymph node was studied. Morphologically, nine cases were diagnosed as HLRCC, three clear cells, two cases with clear and papillary cell, one medullary and one oncocytoma. Genetic findings revealed mutations in NF2, FH,VHL, SMARCB1, HOBB13, ARID1B, B2M, EP300, BCORL1 and MGA. Concurrent coexistence of NF2 and FH mutations was present in 9 cases. Three patients with concurrent FH and NF2 mutations died of the disease.

Conclusions: NF2 mutations have been identified in a variety of morphologic types of Renal cell cancer. However, we were surprised by the number of cases with NF2 mutation in tumors that also harbor the FH (HLRCC) mutation. NF2 tumors have been reported to have an aggressive behavior, and FH cancers are also known to have poor survival. Genomic studies of renal cancers is recommended since some genetic alterations are targetable and may provide adequate therapies that will lead to longer survivals.

Citation Format: Khaled Bin Satter, Liqian Xi, Christopher Rickets, William M. Linehan, Maria J. Merino. NF2 mutations are enriched in FH deficient renal cell 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 5048.
Abstract 5108: Immunomodulatory and anti-tumor effect of radiation and induced telomere damage to treat pediatric high-grade gliomas
Authors: Banlanjo Umaru , Kumar Shiva Senthil , Gryaznov Sergei , Drissi Rachid
Published: March 2024

Pediatric high-grade gliomas (pHGGs), including diffuse intrinsic pontine glioma (DIPG) are among the most treatment refractory cancers in children. Despite multimodal therapy, prognosis is dismal with survival of <1 year for DIPG and a 5-year overall survival <10% for other pHGGs. Radiotherapy remains the only standard of care for DIPG that extends the survival by few months. In recent years, immunotherapy is emerging as a potential alternative treatment option. However, several factors have hindered the use of immunotherapy for pHGGs including “cold” immune environment with lack of immune cells infiltration, low tumor mutational burden, and lack of neo-antigen expression that prevents tumor recognition by the immune system. Therefore, novel therapies that activate the immune system while evading the tumor immunosuppression are highly needed. Here, we aim to demonstrate the immunomodulatory anti-tumor effects of THIO (6-thio-2’deoxyguanosine), a nucleoside analog and a telomerase-dependent telomere targeting agent, in DIPG mouse models. Our preclinical in vitro and in vivo data have demonstrated the efficacy of THIO in inducing telomeric damage, G2/M cell cycle arrest, and apoptosis in high-risk medulloblastoma and DIPG. Importantly, we have demonstrated that THIO crosses the blood-brain barrier and specifically targets tumor cells in an orthotopic mouse model of DIPG. THIO was shown to induce anti-tumor immunity through micronuclei formation leading to cGAS-STING pathway mediated activation of the innate and adaptive immune response in colon, lung, and hepatocellular carcinoma tumor models. Our preliminary data demonstrate the THIO-dependent induction of micronuclei formation co-localizing with cGAS and leading to STAT1 activation in DIPG cell lines. We have also shown that THIO synergistically sensitizes DIPG cells to ionizing radiation (IR), significantly decreasing cell proliferation. We are currently testing the combination of THIO+IR in an orthotopic mouse model for DIPG. We will present results on the potential of THIO and IR treatments to stimulate anti-tumor immunity through the activation of STING pathway in a syngeneic mouse model of DIPG. These preclinical studies will support the potential use of THIO and IR to treat children with high-risk pediatric brain tumors.

Citation Format: Umaru Banlanjo, Shiva Senthil Kumar, Sergei Gryaznov, Rachid Drissi. Immunomodulatory and anti-tumor effect of radiation and induced telomere damage to treat pediatric high-grade gliomas [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 5108.
Abstract 512: Cell-cycle inhibition may influence differences in 2D vs 3D tumor sensitivity profiles
Authors: Kumar Jahanvi , Maestri Chiara , Nitiyanandan Rajeshwar , Trus Ivan , Parker Ricardo J. , Apfel Brigitte , Apfel Christian
Published: March 2024

Background: Traditional cell culture methods involve growing cells on flat surfaces, which do not fully replicate the human physiological conditions. In contrast, 3D cell cultures accurately reproduce aspects of the in-vitro malignant and non-malignant cell behavior. However, differences in tumor sensitivity platforms between 2D vs. 3D models might be relevant for some, but not for other drugs.

Methods: The colorectal cancer cell line HCT-116 was cultured and plated in flat bottom well plates for the 2D condition and in Ultra Low Attachment round-bottom plates for the 3D condition. After plating, cells were treated with chemotherapies and targeted therapies for four days; cellular sensitivity was assessed through a viability assay. Four-parameter logistic (4PL) dose response curves were generated and IC50s were quantified to understand the differences in responses between 2D and 3D cellular environments.

Results: HCT-116 exhibited similar responses to platinum drugs, taxanes, and several other tested drugs in both platforms, with the exception of gemcitabine (2D IC50 0.04 mcM; 3D IC50 12.8 mcM), lapatinib (2D IC50 23; 3D IC50 418), tucatinib (2D IC50 23.3; 3D IC50 79.3), and palbociclib (2D IC50 7.0; 3D IC50 24.0). Interestingly, these drugs share a common mechanism of action, which is the inhibition of cell cycle progression from G1 to S phase. Hence, we hypothesize that this shared mechanism may account for the observed differences in drug efficacy between the two environments.

Conclusions: Similar dose responses have been observed with various drugs on both platforms, yet drugs that inhibit cell cycle progression from G1 to S phase, revealed higher sensitivity in 2D and more resistance in the 3D platform. Confirmatory cell-cycle results analyses are in progress. Further research is needed to understand if this applies to patient samples.

Citation Format: Jahanvi Kumar, Chiara Maestri, Rajeshwar Nitiyanandan, Ivan Trus, Ricardo J. Parker, Brigitte Apfel, Christian Apfel. Cell-cycle inhibition may influence differences in 2D vs 3D tumor sensitivity profiles [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 512.
Abstract 515: Endocycling cancer cells undergo multiple S phases while repressing myc activity
Authors: Loycano Michael A. , Pienta Kenneth J. , Amend Sarah R.
Published: March 2024

Chemotherapy resistance remains a major challenge when treating patients with metastatic cancer. While intrinsic resistance to therapy has been well studied, phenotypic plasticity that drives entry and exit of resistant cell states is poorly understood. One of these plastic cell states used by cancer cells under chemotherapy treatment is characterized by the reprogramming of the mitotic cell cycle to enter a non-proliferative endocycle. Cells in this endocycling state decouple DNA synthesis from cell division by actively progressing through G1, S, and G2 phases of the cell cycle while repeatedly skipping mitosis. After a dormant period, cells can switch back to a mitotic cell cycle to repopulate a tumor. The underlying mechanisms that drive this cell cycle reprogramming remain unknown. C-myc is an oncogenic transcription factor that is dysregulated in ~70% of human cancers. C-myc is responsible for the activation of several cell cycle drivers, including cyclins and CDKs, and represses cell cycle inhibitors, such as CDK inhibitors. High levels of myc activity allow cells to move through the cell cycle quickly with a rapid doubling time. Documented endocycles in polyploid cells rely on high c-myc activity; however, our data shows that endocycling cancer cells have repressed levels of c-myc protein and transcriptional activity. Transcriptomic data shows that myc target genes are expressed at very low levels compared to the mitotic parental cells, and complementary data shows low protein levels. While myc downregulation is expected in non-proliferative cells, the compensatory mechanisms mediating the G1/S transition in the cancer endocycle remain unknown. Recent data has shown that myc suppression alone is not sufficient to induce a sustained endocycle at a population level, despite premature APCCdh1 activation during G2 in a subset of cells. We hypothesize that restoring myc activity to the levels of mitotic parental cells will drive endocycling cells to resume a proliferative mitotic cell cycle and produce mitotic progeny cells. Understanding the mechanisms that govern this transition is crucial to generate next-generation cancer therapeutics to disrupt endocycling cells, blocking acquired resistance and disease recurrence.

Citation Format: Michael A. Loycano, Kenneth J. Pienta, Sarah R. Amend. Endocycling cancer cells undergo multiple S phases while repressing myc activity [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 515.
Abstract 5155: CD8+ T cells and CD4+central memory T cells as biomarkers of perioperative anti-PD-1 therapy in combination with concurrent chemoradiotherapy for locally advanced G/GEJ adenocarcinoma
Authors: Wang Yue , Chen Yawei , Yang Ju , Zhou Xiaoyu , Wei Yutao , Liu Qin , Yang Yang , Guan Wenxian , Liu Baorui , Wei Jia
Published: March 2024

Background: Gastric or gastroesophageal junction (G/GEJ) adenocarcinoma is one of the most common lethal malignancies in the world. Near half of the G/GEJ adenocarcinoma are locally advanced at diagnosis and with poor prognosis. Several clinical trials including SHARED (ChiCTR1900024428), which conducted in our center, demonstrated that perioperative anti-PD-1 therapy in combination with concurrent chemoradiotherapy for locally advanced G/GEJ cancers, could raise the pCR rate over 30%. However, the biomarkers for patients with pCR are nor clear.

Methods: Baseline tumor biopsies and post-treatment surgical tissues were collected for next-generation sequencing (NGS) and mass cytometry (CyTOF). The overall survival (OS) was measured from the date of surgery to the date of death or the last follow-up visit.

Results: 34 patients with locally advanced G/GEJ cancer received anti-PD-1 therapy (Sintilimab) in combination with concurrent chemoradiotherapy in our center. Our results met the pre-specified primary endpoint, with a pCR rate of 38.2% (13/34) and median DFS of 17.0 months. Tumor mutation burden (TMB) analyzed by NGS was higher in the pCR group than those not achieving pCR (non-pCR). Deletion of cytoband 7q35, where TPK1 locates, was significantly enriched in pCR groups. The RNA sequencing data revealed an enrichment of dendritic cells (DC), CD8+ T cells and cytotoxic cell signatures in the pCR group. Conversely, the signature for CD4+ central memory T cells (TCM) was observed to be lower in the pCR group. On the other hand, CyTOF data also demonstrated that the proportion of CD8+ T cells, CD8+ effector memory T cells (TEM) were both higher in pCR group at baseline, while CD4+ TCM was lower. Moreover, the proportion of specific subtype characterized by CD127+CD27+CD45RO+CXCR5-CD4+ TCM was significantly lower in pCR patients and significantly reduced after treatment. As continuous variable, only CD8+ T cells correlated with OS.

Conclusions: It seemed that CD8+ T cells and CD4+ TCM cells could be predictive biomarkers of perioperative anti-PD-1 therapy in combination with cCRT for locally advanced G/GEJ. Furthermore, we found a new CD4+ TCM subtype defined with CD127+CD27+CD45RO+CXCR5- could be novel biomarkers.

Citation Format: Yue Wang, Yawei Chen, Ju Yang, Xiaoyu Zhou, Yutao Wei, Qin Liu, Yang Yang, Wenxian Guan, Baorui Liu, Jia Wei. CD8+ T cells and CD4+central memory T cells as biomarkers of perioperative anti-PD-1 therapy in combination with concurrent chemoradiotherapy for locally advanced G/GEJ adenocarcinoma [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 5155.
Abstract 516: The role of clathrin-mediated endocytosis of EGFR in glioblastoma cell viability and cell cycle progression
Authors: Deter Aaron , Tsung Andrew J. , Guda Maheedhara R. , Asuthkar Swapna , Velpula Kiran
Published: March 2024

Glioblastoma (GBM) is characterized by poor prognosis and overexpression of epidermal growth factor receptor (EGFR). EGFR signaling is regulated through endocytosis, including clathrin-mediated endocytosis. We hypothesized that clathrin-mediated EGFR endocytosis promotes GBM cell viability and proliferation. Analysis of patient data from the Gliovis database revealed decreased overall survival in GBM patients with above-median clathrin expression (n=262) compared to below-median expression (n=263, p<0.05). Immunocytochemistry and Western blot analysis confirmed increased clathrin levels in GBM patient samples compared to normal brain tissue (n=15, p<0.01). To determine the functional effect of inhibiting clathrin-mediated endocytosis, U87 and U251 GBM cells were treated with 15 μM Pitstop-2, a clathrin inhibitor, for 24 hours. Pitstop-2 significantly reduced clathrin levels and cell viability by 40% compared to control (p<0.001, n=3). Cell cycle analysis by flow cytometry revealed Pitstop-2 treatment led to G2/M arrest in both cell lines versus control (p<0.01, n=3). Together, these findings indicate clathrin-mediated endocytosis of EGFR may promote GBM cell viability and proliferation. Further studies on the effects of clathrin inhibition on EGFR signaling and tumor growth in vivo will elucidate the therapeutic potential of targeting this pathway.

Citation Format: Aaron Deter, Andrew J. Tsung, Maheedhara R. Guda, Swapna Asuthkar, Kiran Velpula. The role of clathrin-mediated endocytosis of EGFR in glioblastoma cell viability and cell cycle progression [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 516.
Abstract 5169: Circulating levels of ANGPTL3, PCSK9, apoCIII and lipoprotein (a) in high-grade serous ovarian cancer
Authors: Chong Emilie Wong , Joncas France-Hélène , Douville Pierre , Bachvarov Dimcho , Calon Frédéric , Seidah Nabil , Diorio Caroline , Gangloff Anne
Published: March 2024

Background: Ovarian cancers require abundant amounts of lipids for their growth. Recent years have highlighted the role of ANGPTL3, PCSK9, ApoCIII and Lp(a) as key players in lipid metabolism. But circulating levels of these factors in ovarian cancers have not been thoroughly investigated to date.

Objective: We assessed the profiles of plasma ANGPTL3, PCSK9, ApoCIII and Lp(a) in ovarian high-grade serous carcinoma (HGSC).

Methods: Plasma samples collected from women diagnosed with an HGSC (n=31) or a benign ovarian lesion (BOL, n=40) were analyzed for plasma lipid profile (ApoB, total cholesterol, HDL, triglycerides, Lp(a) levels) on a clinical modular platform (Roche). ApoCIII, ANGPTL3 and PCSK9 levels were measured with commercially-available ELISA kits. Differences between HGSC and BOL were assessed by two-group comparisons. Pairwise correlation strength between variables was evaluated with Spearman’s rank order tests. Logistic regression modelling was used to further examine the associations between selected variables and HGSC diagnoses.

Results: ANGPTL3 levels increased in HGSC (84.1 ng/ml, SD=29.2ng/ml, n=31) compared to BOL (66.9ng/ml, SD=30.7 ng/ml, n=40; HGSC vs BOL p=0.02). Receiver operating characteristic (ROC) curve suggested that plasma ANGPTL3 levels were moderately associated with HGSC (AUC=67.7%, p=0.005 1) and did not increase predictive performance of ovarian tumor biomarkers CA125 and HE4 in multivariable model. Associations between ANGPTL3 levels and cholesterol (HDL, non-HDL, LDL and total) could be observed in the control group but not in the HGSC group. The same dissociation was observed for the inverse correlation between HDL and triglycerides in HGSC. Furthermore, moderate associations were observed between PCSK9 & CA19-9 in the entire cohort (rho=0.34, n=53, p=0.013) and Lp(a) & CA125 in HGSC cases (rho=0.51, p= 0.017).

Conclusion: In this cohort of 71 women, we report increased levels of ANGPTL3 in HGSC with an effect size (Cohen’s D) of 0.57. Confirmation of this result in larger cohort studies (minimal n>50 in each group) would warrant further investigation into the roles of circulating ANGPTL3. Its inhibition may allow to tackle deregulated lipid metabolic pathways contributing to ovarian cancer progression.

Citation Format: Emilie Wong Chong, France-Hélène Joncas, Pierre Douville, Dimcho Bachvarov, Frédéric Calon, Nabil Seidah, Caroline Diorio, Anne Gangloff. Circulating levels of ANGPTL3, PCSK9, apoCIII and lipoprotein (a) in high-grade serous ovarian 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 5169.