bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 778: CD24 mutant p53 contribute to racial disparities in prostate cancer
Authors: Cui Xuelian , Wang Shuaibin , Wang Lizhong
Published: July 2021

African-American (AA) men have the highest rate of prostate cancer among racial or ethnic groups. CD24, a cell-surface protein anchored by glycosyl-phosphatidyl-inositol (GPI), often is over-expressed in cancers and serves as a marker for poor prognosis of human cancer, including prostate cancer. Using a functional analysis of prostate cancer cells, we found a CD24-dependent inactivation of mutant p53, but the clinical significance of this observation remained uncertain. Here, we validated these results with samples of human prostate cancer and explored the role of a CD24-p53 axis in racial disparities of prostate cancer. Our bioinformatics analysis of public datasets, including TCGA data, confirmed higher levels of CD24 mRNA expression in late-stage and metastatic prostate cancer. In the present study, we addressed the association of CD24 with mutant p53 and their differential expression between AA and European-American (EA) prostate cancers and assessed whether cells with CD24 and mutant p53 contribute to health disparities in prostate cancer. CD24, mutant p53, MDM2, and ARF proteins were expressed in 55%, 24%, 39%, and 68% of prostate cancer samples, respectively. CD24 and mutant p53 were present more frequently in late-stage and metastatic prostate cancer. The presence of CD24 was associated with a > 4-fold risk of metastasis, which included lymph node and distant metastases. H-score analysis showed positive correlations of CD24 expression with mutant p53 and MDM2. A racial disparity was evident for CD24 but not for mutant p53. In 32 CD24+/mutant p53+ cases, a TP53R273H mutation was found in five cases, but no TP53R175H mutation was found. The CD24-p53 axis may contribute to aggressive and metastatic prostate cancers, especially those of AAs.

Citation Format: Xuelian Cui, Shuaibin Wang, Lizhong Wang. CD24 mutant p53 contribute to racial disparities in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 778.
Abstract 809: Neurotensin increases tyrosine phosphorylation of HER3
Authors: Moody Terry W. , Ramosalvarez Irene , Jensen Robert T.
Published: July 2021

Neurotensin (NTS) is an autocrine growth factor for non-small cell lung cancer cells. NTS stimulates and the NTSR1 antagonist SR48692 inhibits NSCLC growth (Moody et al., Life Sci 2014; 100: 25). NSCLC patients, whose tumors have high NTSR1, have significantly lower relapse-free survival than those with low NTSR1 (Younes et al., Oncotarget 2014; 5: 8252). NTS addition to NSCLC cells increases the tyrosine phosphorylation of the EGFR and HER2 (Moody et al., Eur J Pharmacol 2019; 865:172735). Activation of HER3 in NSCLC mediates aggressive growth and drug resistance. Therefore the ability of NTSR1 to regulate transactivation of HER3 was investigated. By RT-PCR, HER3 and NTSR1 but not NTSR2 mRNA was present in NSCLC cells. NTS addition to NCI-H358 or H441 cells increased HER3 and ERK tyrosine phosphorylation by 210% and 240%, respectively and the increase caused by NTS was antagonized by SR48692 or mAb3481 (HER3 mAb). The increase is phosphorylation of Tyr1289-HER3 caused by NTS or neuregulin-1 addition to NSCLC cells was due to the formation of HER2-HER3 and EGFR-HER3 heterodimers. NTSR1 regulation of HER3 or Akt phosphorylation was impaired by PP2 (Src inhibitor) or GM6001 (MMP inhibitor). Because N-acetylcysteine (antioxidant) or Tiron (superoxide scavenger) inhibited the ability of NTS to increase HER3 phosphorylation, reactive oxygen species (ROS) are essential. Using a clonogenic assay, NTS increased NSCLC colony number whereas SR48692 or mAb3481 reduced colony number. The results indicate that NTS increased HER3 tyrosine phosphorylation in a ROS-/Src-/MMP-dependent manner. In summary, NTSR1 transactivates HER3 resulting in ERK and Akt phosphorylation increasing the proliferation and survival of NSCLC cells.

Citation Format: Terry W. Moody, Irene Ramosalvarez, Robert T. Jensen. Neurotensin increases tyrosine phosphorylation of HER3 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 809.
Abstract 825: Genetically determined elevated C-reactive protein levels and chronic inflammation status associated with primary colorectal cancer risk: Mendelian randomization with lifestyle interactions
Authors: Jung Su Yon , Yu Herbert , Pellegrini Matteo , Papp Jeanette C. , Sobel Eric M. , Zhang Zuo-Feng
Published: July 2021

Purpose: Immune-related etiologic pathways in the development of colorectal cancer (CRC) have not been convincingly determined and may be confounded by lifestyle factors or reverse causality. We investigated the genetically predicted C-reactive protein (CRP) phenotype in the potential causal pathway of primary CRC risk in postmenopausal women in a Mendelian randomization (MR) framework.

Methods: We employed individual-level data of the Women's Health Initiative Database for Genotypes and Phenotypes Study, which consists of 5 genome-wide association (GWA) studies, including 10,142 women, 737 of whom developed primary CRC. We examined 61 GWA single-nucleotide polymorphisms (SNPs) associated with CRP by using weighted/penalized MR weighted-medians and MR gene-environment interactions that allow some relaxation of the strict variable requirements and attenuate the heterogeneous estimates of outlying SNPs.

Results: In lifestyle-stratification analyses, genetically determined CRP exhibited its effects on the decreased CRC risk in non-viscerally obese and high-fat diet subgroups. In contrast, genetically driven CRP was associated with an increased risk for CRC in women who smoked 15 or more cigarettes/day, with significant interaction of the gene-smoking relationship. Further, a substantially increased risk of CRC induced by CRP was observed in relatively short-term users (less than 5 years) of estrogen (E)-only and also longer-term users (longer than 5 years) of E plus progestin.

Conclusions: Our findings may provide novel evidence on immune-related etiologic pathways connected to CRC risk and suggest the possible use of CRP as a CRC-predictive biomarker in women with particular behaviors and CRP marker-informed interventions to reduce CRC risk.

Citation Format: Su Yon Jung, Herbert Yu, Matteo Pellegrini, Jeanette C. Papp, Eric M. Sobel, Zuo-Feng Zhang. Genetically determined elevated C-reactive protein levels and chronic inflammation status associated with primary colorectal cancer risk: Mendelian randomization with lifestyle interactions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 825.
Abstract 829: Genetic risk factors for histiocytic sarcoma in a canine disease model
Authors: Evans Jacquelyn M. , Parker Heidi G. , Plassais Jocelyn , Rutteman Gerard R. , Ostrander Elaine A.
Published: July 2021

Histiocytic sarcoma is a rare, aggressive hematopoietic malignancy of mature tissue histiocytes with a poorly understood etiology in humans. A histologically and clinically similar counterpart in dogs affects two breeds at unusually high frequency, with 20-25% of Flatcoated Retrievers and Bernese Mountain Dogs developing histiocytic sarcoma, while the disease is extremely rare in other breeds. In this study, we leveraged the canine model system to investigate genetic risk factors for histiocytic sarcoma in the Flatcoated Retriever. Population bottlenecks and artificial selection during breed formation within last 200 years have created the unique breed structure in dogs, characterized by long linkage disequilibrium and low within-breed genetic diversity. This allows for the identification of disease-associated traits with relatively few markers and individuals. We conducted multiple genome-wide association studies in Flatcoated Retrievers in which we identified two loci conferring risk for histiocytic sarcoma (177 cases and 132 controls, total). The first locus, on canine chromosome (CFA) 5, also colocalizes with previously identified risk for hemangiosarcoma and B-cell lymphoma, two hematopoietic malignancies in the closely related golden retriever breed. The second locus is unique to the Flatcoated Retriever and increases risk for histiocytic sarcoma in combination with CFA5. There have been multiple reports of human histiocytic sarcoma diagnosis concurrent with other hematological cancers, including lymphoma, suggested to be the result of transdifferentiation or a common neoplastic progenitor. Here we link germline predisposition for histiocytic sarcoma and B-cell lymphoma to the same locus in retrievers. Subsequent whole genome, transcriptome, and ChIP sequencing, highlighted candidate genes at each locus with roles in cell migration, as well as candidate regulatory variants with predicted impact on transcription factor binding. This comprehensive, multi-omics approach has been previously largely unexplored in the canine model. Here we advance our knowledge of the biology of histiocytic sarcoma, which will have direct impact on canine health and elucidate the genetic mechanisms underlying a rare human cancer.

Citation Format: Jacquelyn M. Evans, Heidi G. Parker, Jocelyn Plassais, Gerard R. Rutteman, Elaine A. Ostrander. Genetic risk factors for histiocytic sarcoma in a canine disease model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 829.
Abstract 830: Validity and reproducibility of immunohistochemical scoring by trained non-pathologists on Tissue MicroArrays
Authors: Offermans Kelly , Jenniskens Josien C. , Samarska Iryna , Fazzi Gregorio E. , Simons Colinda C. , Smits Kim M. , Schouten Leo J. , Weijenberg Matty P. , van den Brandt Piet A. , Grabsch Heike I.
Published: July 2021

Aims: Scoring of immunohistochemical (IHC) staining is often done by non-pathologists, especially in large-scale Tissue MicroArray (TMA)-based studies. Studies on the validity of scoring results from non-pathologists are very limited. Therefore, our main aim was to assess inter-observer agreement between trained non-pathologists and an experienced histopathologist for three IHC markers with different subcellular localisation (nucleus/membrane/cytoplasm).

Methods and results: Three non-pathologists were trained in recognizing adenocarcinoma and IHC scoring by a senior histopathologist. Kappa statistics were used to analyse inter- and intra-observer agreement for 6249 TMA cores from a colorectal cancer (CRC) series. Inter-observer agreement between non-pathologists (independently scored) and the histopathologist was “substantial” for nuclear and membranous IHC markers (κrange=0.67-0.75 and κrange=0.61-0.69, respectively), and “moderate” for the cytoplasmic IHC marker (κrange=0.43-0.57). Scores of the three non-pathologists were also combined into a combination score (if at least two non-pathologists independently assigned the same score to a core, this was the combination score). This increased agreement with the pathologist (κnuclear=0.74; κmembranous=0.73; κcytopasmic=0.56). Inter-observer agreement between non-pathologists was “substantial” (κnuclear=0.78; κmembranous=0.72; κcytopasmic=0.61). Intra-observer agreement of non-pathologists was “substantial” to “almost perfect” (κnuclear,range=0.83-0.87; κmembranous,range=0.75-0.82; κcytopasmic,range=0.69-0.69). Overall, agreement was lowest for the cytoplasmic IHC marker.

Conclusions: This study shows that adequately trained non-pathologists are able to produce similar IHC scoring results as an experienced histopathologist. Considering the histopathologist's score as the golden standard, we can conclude that trained non-pathologists can produce valid IHC results on TMA sections. A combination score of at least two non-pathologists yielded optimal results.

Citation Format: Kelly Offermans, Josien C. Jenniskens, Iryna Samarska, Gregorio E. Fazzi, Colinda C. Simons, Kim M. Smits, Leo J. Schouten, Matty P. Weijenberg, Piet A. van den Brandt, Heike I. Grabsch. Validity and reproducibility of immunohistochemical scoring by trained non-pathologists on Tissue MicroArrays [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 830.
Abstract 86: O-GlcNAc transferase regulates glioblastoma acetate metabolism via regulation of CDK5-dependent ACSS2 phosphorylation
Authors: Ciraku Lorela , Bacigalupa Zachary , Moeller Rebecca , Ju Jing , Lee Rusia H. , Ferrer Christina , Trefely Sophie , Snyder Nathaniel W. , D'Agostino Luca , Katsetos Christos D. , Shi Wenyin , Reginato Mauricio J.
Published: July 2021

Cancer cells alter their metabolism to increase cell growth. A subset of the glucose taken up is shunted into the hexosamine biosynthetic pathway where it is used to synthesize UDP-GlcNAc, a substrate of O-GlcNAc transferase (OGT), which modifies cytoplasmic and nuclear proteins with O-linked sugar moieties. Here, we show that OGT and O-GlcNAcylation are elevated in glioblastoma (GBM) cancer cells and in GBM patient samples that correlates with disease progression. Reduction of OGT expression in GBM cells led to significant reduction in anchorage-independent growth, acetyl-CoA levels, and decrease in free fatty acids. Conversely, overexpressing OGT in GBM cells had the opposite effect. Reducing OGT expression in GBMcells transplanted in an orthotopic intracranial mouse model reduced tumor growth and extended survival. Mechanistically, we show that OGT overexpression increases carbon-flux of acetate to acetyl-CoA, a reaction carried by the enzyme acetyl-CoA synthetase 2 (ACSS2). Indeed, OGT regulates ACSS2 protein levels and O-GlcNAcylation increases ACSS2phosphorylation on Ser-267 in a cyclin dependent kinase 5 (CDK5)-dependent manner, which regulates its stability by reducing polyubiquitination and degradation. ACSS2 Ser-267 is critical for OGT-mediated GBM growth as overexpression of ACSS2 Ser-267 phospho-mimetic rescues growth in vitro and in vivo. Using an ex vivo GBM brain slice model we show that treatment of GBM-transplanted slices with OGT inhibitor Ac-GlcNAc-5S or pan-cdk inhibitor dinaciclib reduced growth of pre-formed tumors in cultured brain slices. These results suggest a crucial role for O-GlcNAc signaling in transducing nutritional state to regulate acetate metabolism and identify OGT and CDK5 as novel therapeutic targets for treatment of glioblastoma.

Citation Format: Lorela Ciraku, Zachary Bacigalupa, Rebecca Moeller, Jing Ju, Rusia H. Lee, Christina Ferrer, Sophie Trefely, Nathaniel W. Snyder, Luca D'Agostino, Christos D. Katsetos, Wenyin Shi, Mauricio J. Reginato. O-GlcNAc transferase regulates glioblastoma acetate metabolism via regulation of CDK5-dependent ACSS2 phosphorylation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 86.
Abstract 862: Transcriptomics analysis reveals unique immunoinflammatory signatures of nigerian prostate cancer
Authors: Rotimi Solomon Oladapo , Omonisi Abidemi E. , Mohammed Faruk , Jibrin Paul , Duduyemi Babatunde , Olusina Daniel B. , Xu Yili , Jin Yuxin , Liu Xiyu , Xiao Guang Q. , Odedina Folakemi , Carpten John , Reams Renee , Manojlovic Zarko
Published: July 2021

Background: Prostate cancer (PCa) is the leading cause of cancer death among Nigerian men, with most men presenting late and with high grade disease. Furthermore, improved PCa diagnosis and treatment could rely on genomics-driven precision approaches. Mounting evidence supports potential population enriched molecular features of cancer, however the extent of which is hampered due to a dearth of genomic data in diverse cohorts. This study, therefore, aims at utilizing transcriptomics analysis to deduce transcriptional states in PCa from Nigerian men.

Methodology: RNA was extracted from macro-dissected prostate tumor and adjacent normal tissue from 35 archival formalin fixed paraffin-embedded (FFPE) blocks from Gleason 8-9 cancers, of which 25 had cribriform morphologic architecture. High resolution hybrid-capture mRNA-seq libraries were sequenced using Illumina NovaSeq 6000 system and generated an average of 124 million read pairs per sample. Raw reads were processed using a custom pipeline based upon industry standard algorithms along with the deduction of genetic ancestry. Molecular annotation was also performed to investigate tumor and immune cell heterogeneity.

Result: The Nigerian data were compared with high grade PCa data of Caucasian obtained from TCGA. The Nigerian PCa tumors where characterized with uniquely enriched immune-inflammatory microenvironment which include crosstalk between dendritic cells and natural killer cells, and natural killer cell signaling. While the Nigerian tumors share more features of distal metastatic tumor, their enrichment in NKT Cells is a unique feature.

Conclusion: This represents the first report of RNA-seq analysis of PCa in Sub-Saharan Africa and the unique transcriptomics features of Nigerian PCa presents opportunities for precision intervention in addressing its burden in Nigeria.

Citation Format: Solomon Oladapo Rotimi, Abidemi E. Omonisi, Faruk Mohammed, Paul Jibrin, Babatunde Duduyemi, Daniel B. Olusina, Yili Xu, Yuxin Jin, Xiyu Liu, Guang Q. Xiao, Folakemi Odedina, John Carpten, Renee Reams, Zarko Manojlovic. Transcriptomics analysis reveals unique immunoinflammatory signatures of nigerian prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 862.
Abstract 871: KYNU expression is a prognostic factor in KEAP1/STK11 co-mutated lung adenocarcinoma
Authors: Cai Ling , Rogers Thomas J. , Li Huiyu , Kim Jiyeon , Xie Yang , Xiao Guanghua , Minna John , DeBerardinis Ralph J.
Published: July 2021

We searched for gene expression prognostic markers with bimodal distribution in lung adenocarcinoma (LUAD) that might help specify molecular subtypes and identified a highly consistent biomarker KYNU, an enzyme in the pathway that converts tryptophan to nicotinamide adenine dinucleotide (NAD+). KYNU performed better in predicting LUAD outcomes than genes in related pathways. High KYNU expression is particularly observed in tumors with mutations in the tumor suppressor genes KEAP1 and STK11, but not in the oncogene KRAS. From clinical data of LUAD, we found more frequent co-mutation of KEAP1 and STK11 than KRAS with either KEAP1 or STK11. Tumors with mutations in both KEAP1 and STK11 had poorer outcomes than tumors with mutations in neither or only one of these genes, regardless of KRAS status. Importantly, KYNU expression associated with poor outcomes regardless of KEAP1/STK11 status and other covariates. We also assessed clinical features associated with KEAP1/STK11 mutations with AACR GENIE data. By examining co-expression of KYNU with other genes, we determined that high KYNU expression had low expression of gene sets related to macrophages.

Citation Format: Ling Cai, Thomas J. Rogers, Huiyu Li, Jiyeon Kim, Yang Xie, Guanghua Xiao, John Minna, Ralph J. DeBerardinis. KYNU expression is a prognostic factor in KEAP1/STK11 co-mutated lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 871.
Abstract 872: Pathogenesis underlying the bidirectional relationship between non-Hodgkin lymphomas and primary Sjögren's Syndrome
Authors: Ma Kevin Sheng-Kai , Chiang Cho-Han , Wang Li-Tzu
Published: July 2021

Introduction: Bidirectional relationship between non-Hodgkin lymphomas (NHLs) and Sjögren's syndrome (SS) has been recognized in large scale cohort studies. To investigate the underlying pathogenesis of this association, we identified highly expressed genes and altered pathways with RNA-sequencing (RNA-seq) data from SS and NHLs patients.

Methods: Canonical pathway analysis was conducted by comparing RNA-seq data from whole-transcriptome expression profiling to identify underlying pathogenesis among NHL patients with Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL), or marginal zone lymphoma (MZL), and SS patients. Collected biopsies included lymphoma biopsies for NHLs, including BL (n = 59), DLBCL (n = 88), FL (n = 65), MCL (n = 43), and MZL (n = 23), sorted B cells from healthy donors (n=10), as well as parotid gland tissues for SS (n=17). Fold changes and z-scores were derived after normalized by the expression levels among controls. RNA-seq data with P values less than 0.05 or -log10(P) values larger than 1.3 were considered significantly expressed. Positive z-scores indicated up-regulation while negative z-scores indicated down-regulation.

Results: There were 17 identified significantly expressed genes (P < 0.05 for all NHLs and SS), including well-known cancer-associated genes CXCL13, COL1A1, IGFBP7, COL3A1, CXCL9, CXCL12, CCL19, and CLU. Among them, CXCL13 was the most expressed gene involved in NHLs and SS. The fold changes of CXCL13 were 14.09, 465.57, 319.51, 369.70, 817.63, and 4.03 for BL, DLBCL, FL, MCL, MZL, and SS, respectively. Among all identified pathways underlying SS and NHL development, which were ordered based on the sum of z-scores, the endocannabinoid system-driven cancer inhibition pathways were the most significantly altered in both SS and NHLs, followed by interferon-involved antiviral responses, when compared to matched healthy controls. The z-scores of the cancer inhibition pathways were -0.14 for BL (-log10(P) = 4.54), -1.30 for DLBCL (-log10(P) = 3.00), -0.33 for FL (-log10(P) = 4.67), -0.87 for MCL (-log10(P) =3.77), -2.61 for MZL (-log10(P) = 4.31), and -1 for SS (-log10(P) = 1.44).

Conclusion: The underlying pathogenesis for SS-associated NHL development involved 17 highly expressed genes, including CXCL13, and down-regulated cancer inhibition pathways.

Citation Format: Kevin Sheng-Kai Ma, Cho-Han Chiang, Li-Tzu Wang. Pathogenesis underlying the bidirectional relationship between non-Hodgkin lymphomas and primary Sjögren's Syndrome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 872.
Abstract 875: Associations of aspirin and other anti-inflammatory medications with breast cancer risk by the status of COX2 receptor
Authors: Yaghjyan Lusine Na , Eliassen Heather , Colditz Graham , Rosner Bernard , Wijayabahu Akemi , Tamimi Rulla
Published: July 2021

Purpose: We investigated the associations of aspirin and other non-steroid anti-inflammatory drugs (NSAIDs) with breast cancer risk by the status of COX2 receptor expression.

Methods: This study included 421 cases and 3,166 controls from a nested case-control study within the Nurses' Health Study (NHS) and Nurses' Health Study II (NHSII) cohorts. Information on medication use was first collected in 1980 (NHS) and 1989 (NHSII) and was updated biennially. Medication use was defined as none, past or current; average cumulative dose and frequency were calculated for all past or current users using data collected from all bi-annual questionnaires preceding the reference date. Immunochemistry for COX2 expression was performed using commercial antibody (Cayman Chemical and Thermo Fisher Scientific). We used polychotomous logistic regression to quantify associations of aspirin and NSAIDs with the risk of COX2+ and COX2- breast cancer tumors, while adjusting for known breast cancer risk factors. All tests of statistical significance were two-sided.

Results: In multivariate analysis, heterogeneity tests indicated statistically significant differences in associations of most of the aspirin exposures and regular use of NSAIDs with breast cancer risk by COX2 receptor status. However, we observed no distinct differences in the patterns of associations between COX2+ and COX2- tumors for any of the exposure variables. Significant associations of these medications with breast cancer risk were observed for dosage of aspirin among current users in COX2- tumors (OR for >5 tablets per week vs. none 1.71, 95% CI 1.01-2.88, p-trend 0.04) Regular aspirin use was marginally associated with the risk of COX2- tumors (p-trend=0.06) only (p-heterogeneity<0.0001).

Conclusions: Our findings suggested no differences in associations of aspirin and other NSAIDs with COX2+ and COX2- tumors.

Citation Format: Lusine Na Yaghjyan, Heather Eliassen, Graham Colditz, Bernard Rosner, Akemi Wijayabahu, Rulla Tamimi. Associations of aspirin and other anti-inflammatory medications with breast cancer risk by the status of COX2 receptor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 875.
Abstract 911: In vitro and in vivo activity of DHES0815A, an antibody-drug conjugate targeting HER2/neu in uterine serous carcinoma
Authors: Tymon-Rosario Joan Tymon R. , Bonazzoli Elena , Bellone Stefania , Manzano Arancha , Manara Paola , Zammataro Luca , Pelligra Silvia , Guglielmi Adele , Gnutti Barbara , Zeybek Burak , Harold Justin , Mauricio Dennis , Ratner Elena , Schwartz Peter , Santin Alessandro D.
Published: July 2021

Objective: Uterine serous carcinoma (USC) is an aggressive histologic variant of endometrial cancer which portends a poor prognosis. DHES0815A is a novel antibody-drug-conjugate (ADC) which binds specifically to HER2 overexpressing tumors at a distinct epitope from that bound by trastuzumab and pertuzumab after which it delivers the toxic payload, PBD-MA, a DNA mono-alkylating agent. The objective of this study was to evaluate the preclinical activity of DHES0815A against primary USC cell lines and xenografts.

Methods: Twelve primary USC cell lines were assessed by immunohistochemistry (IHC) for HER2 protein expression and for C-erbB2 gene amplification using fluorescent in situ hybridization (FISH) analysis. Cell viability and bystander killing in USC cell lines after exposure to DHES0815A, the non-targeted ADC, and the unconjugated antibody (i.e. MHES0488A) were evaluated using flow cytometry-based-assays. In vivo activity of DHES0815A was tested against HER2/neu overexpressing USC xenografts.

Results: High HER2/neu protein expression was seen in 25% (3/12) of the primary USC cell lines. USC cell lines overexpressing HER2/neu were significantly more sensitive to DHES0815A when compared to the non-targeted control ADC (p<0.001). DHES0815A did not induce significant bystander killing of HER2/neu negative tumors when admixed with HER2/neu positive tumors. DHES0815A caused growth-inhibition and increased survival in USC HER2/neu overexpressing xenografts when compared to controls (p<0.01).

Conclusions: DHES0815A is both highly selective and toxic to USC tumors overexpressing HER2/neu both in vitro and in vivo. HER2-directed ADCs, alone or in combination with other HER2/neu targeted agents may represent a novel treatment option for patients with tumors harboring HER2/neu overexpression refractory to trastuzumab and traditional chemotherapy.

Citation Format: Joan Tymon R. Tymon-Rosario, Elena Bonazzoli, Stefania Bellone, Arancha Manzano, Paola Manara, Luca Zammataro, Silvia Pelligra, Adele Guglielmi, Barbara Gnutti, Burak Zeybek, Justin Harold, Dennis Mauricio, Elena Ratner, Peter Schwartz, Alessandro D. Santin. In vitro and in vivo activity of DHES0815A, an antibody-drug conjugate targeting HER2/neu in uterine serous carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 911.
Abstract 922: End-to-end discovery to support the development of safe and efficacious engineered cell therapies
Authors: Vousden Katherine , Holt Sanne , Vermond Sophie , Hazenoot Monique , Ives Sarah , Youssef Sawsan , Glanville Jake
Published: July 2021

The global market for cell and gene therapies, including T-cell/Natural Killer cell chimeric antigen receptors (CAR-T/NK), is continuing to grow rapidly - with many clinical success stories for B-cell malignancies in particular. However, the path to clinical success has not been smooth - with early reports of organ damage and even deaths following CAR-T therapy highlighting that there are significant risks involved in their development, and a clear requirement to understand and mitigate for the underlying mechanisms that result in unwanted toxicities. Off-target binding and tonic signalling are indicated in many pre-clinical and clinical cell therapy failures, and it is becoming increasingly apparent that CAR design - particularly the selection of the tumor targeting moiety with exquisite specificity, desirable biophysical attributes and appropriate affinity - is key to developing a successful therapy. Distributed Bio's scFv and VHH phage-display libraries (SuperHuman 2.0 and Tungsten) have been designed to be biophysically stable and non-immunogenic. Their size and clonal diversity, coupled with the use of streamlined work-flows, enable the rapid identification of large panels of VH CDR3 sequence-unique binders which can then be assessed for CAR suitability by exploiting the integrated approach offered by DBio's successful partnership with Charles River. Panels of CAR constructs, covering the diversity of sequences and affinities related to the scFv/VHH domains isolated, can be triaged through Charles River efficacy and safety work-streams to identify the best therapeutic candidates. For example, co-culture experiments with target-expressing carcinoma cell lines and non-target expressing cell lines can be utilized to investigate and compare activity, specificity and potency of the various CAR constructs. Ultimately, combining Distributed Bio discovery with Charles River downstream characterization enables identification of the best lead candidate - balancing efficacy and safety of your CAR-T therapy - for optimal therapeutic outcome.

Citation Format: Katherine Vousden, Sanne Holt, Sophie Vermond, Monique Hazenoot, Sarah Ives, Sawsan Youssef, Jake Glanville. End-to-end discovery to support the development of safe and efficacious engineered cell therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 922.
Abstract 994: Investigating inhibition of nuclear export in breast cancer cells
Authors: Gruener Robert F. , Greene Geoffrey L. , Huang R. Stephanie
Published: July 2021

XPO1 (Exportin aka CRM1) is a mediator of nuclear export that is known to be dysregulated in cancers. Selective inhibitors of nuclear export (SINEs) have shown some promise in cancer treatment, but the mechanism is poorly understood in cancer specific subtypes. Here, we investigated XPO1 inhibition in breast cancer by treating a panel of breast cancer cell lines with a SINE (Selinexor) and saw a bimodal response, with most triple-negative cell lines showing sensitivity and some ER+ cell lines showing resistance to the therapy. Changes in the expression of BIRC5 (Survivin) have been previously implicated in XPO1 inhibitor response. Using RT-qPCR experiments we were able to show that after 24 hours of selinexor treatment, the expression of BIRC5 does change in two sensitive cell lines MDA-MB-231 and MCF7, but is not necessarily changed at earlier time points. To more holistically explore the mechanism of XPO1 inhibition induced cell death, we performed RNA-Seq and differential gene expression analysis on these two cell lines at 2, 8, and 24 hours post treatment with Selinexor (compared to vehicle). Our results indicate that several breast cancer and cell cycle associated genes show expression changes as early as 2 hours post-treatment and showed-consistent changes across the time-points. Overall, our analysis sheds light on the mechanism by which XPO1 inhibition induces cell death in breast cancer, which may help elucidate potential biomarkers as well as to nominate rationale combinations to explore with XPO1 inhibition.

Citation Format: Robert F. Gruener, Geoffrey L. Greene, R. Stephanie Huang. Investigating inhibition of nuclear export in breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 994.
Abstract 995: Alpelisib and vorinostat modulate critical genes in basal-2 triple negative breast cancer cells and inhibit cell growth and invasion
Authors: Lyn-Cook Beverly D. , Word Beverly , Hammons George , Emamzadeh Fatemeh Nouri
Published: July 2021

Triple negative breast cancer (TNBC) is a heterogeneous disease that continues to be an unmet medicine need. It has a high mortality rate in younger women, especially African Americans. African American women are not sufficiently involved in clinical trials in which novel drugs are being tested. The aggressive and biology of subtypes of this cancer are being researched; however, no targeted therapy has been successful to date. Alpelisib is a selective inhibitor of PIK3 in the PIK3/ATK pathway and has been approved for treatment of advanced metastatic breast cancer. This study was conducted to investigate the effects of Alpelisib and vorinostat (an HDAC inhibitor), either alone or in combination, in the basal-2, a subtype of TNBC, cell line, HCC1806 from a African American woman. Alpelisib alone decreased protein expression of GSKβ, crk and DDX5. Alpelisib significantly upregulated the expression of AKT1 protein. In combination with vorinostat, a synergistic effect was noted with AKT1 protein expression. Different isoforms of AKT has been shown to exert anti-cancer effects. Also, the combination significantly decreased GSKβ protein expression. GSKβ regulates epithelial-mesenchymal transition and cancer stem cell properties. Decreased expression of DDX5 has been shown to result in decreased cell growth. These drugs also decreased invasion. Results from this study suggest that Alpelisib should be further investigated in basal-2 TNBC, alone or in combination with vorinostat.

Citation Format: Beverly D. Lyn-Cook, Beverly Word, George Hammons, Fatemeh Nouri Emamzadeh. Alpelisib and vorinostat modulate critical genes in basal-2 triple negative breast cancer cells and inhibit cell growth and invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 995.
Abstract CT210: Trial in Process: Phase 1 studies of BI 1701963, a SOS1::KRAS Inhibitor, in combination with MEK inhibitors, irreversible KRASG12C inhibitors or irinotecan.
Authors: Hofmann Marco H. , Lu Hengyu , Duenzinger Ulrich , Gerlach Daniel , Trapani Francesca , Machado Annette A. , Daniele Joseph R. , Waizenegger Irene , Gmachl Michael , Rudolph Dorothea , Vellano Christopher P. , Marotti Marcelo , Vucenovic Vitomir , Heffernan Timothy P. , Marszalek Joseph R. , Petronczki Mark P. , Kraut Norbert
Published: July 2021

The SOS1i::KRAS inhibitor BI 1701963 is the first direct RAS signaling modifier to enter phase I clinical trials both as a monotherapy as well as in combination. SOS1::KRAS inhibitors exhibit activity against a broad spectrum of KRAS alleles, including the major G12D/V/C and G13D oncoproteins, while sparing the interaction of KRAS with SOS2. Here, we present pre-clinical data showing enhanced pathway modulation and synergistic anti-tumor effects following vertical pathway inhibition of BI 1701963 in combination with mitogen-activated protein kinase inhibitors (MEKi; trametinib and BI 3011441) or KRAS G12C inhibitors (MRTX849 and BI 1823911). Furthermore, SOS1::KRAS inhibitor treatment sensitizes tumor cells to increased DNA damage in combination with irinotecan. Our results highlight the suitability of SOS1::KRAS inhibitors as a backbone in combination therapies targeting KRAS-dependent tumors. Pre-clinical combination data supported the start of multiple phase I trials investigating the safety, tolerability, recommended dose and preliminary efficacy of BI 1701963 alone and in combination with other anti-cancer agents. Combination trials of BI 1701963 with MEKi include cohorts of patients with KRAS mutant solid tumors, such as non-small cell lung cancer (NSCLC), colorectal cancer (CRC), cholangiocarcinoma and pancreatic adenocarcinoma. Trials exploring the combination of BI 1701963 with irreversible KRAS G12C inhibitors (MRTX849 and BI 1823911) will include cohorts of patients with KRAS G12C mutant NSCLC and CRC. In a further study, the combination of BI 1701963 with irinotecan is being evaluated in patients with KRAS mutant CRC. Primary endpoints include dose-limiting toxicities, treatment-emergent or -related adverse events. Secondary endpoints include pharmacokinetic and pharmacodynamic properties of combination regimens and preliminary efficacy.

Citation Format: Marco H. Hofmann, Hengyu Lu, Ulrich Duenzinger, Daniel Gerlach, Francesca Trapani, Annette A. Machado, Joseph R. Daniele, Irene Waizenegger, Michael Gmachl, Dorothea Rudolph, Christopher P. Vellano, Marcelo Marotti, Vitomir Vucenovic, Timothy P. Heffernan, Joseph R. Marszalek, Mark P. Petronczki, Norbert Kraut. Trial in Process: Phase 1 studies of BI 1701963, a SOS1::KRAS Inhibitor, in combination with MEK inhibitors, irreversible KRASG12C inhibitors or irinotecan. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT210.
Abstract CT232: A phase II study of toripalimab plus anlotinib as maintenance therapy in extensive-stage small cell lung cancer
Authors: Lv Dongqing , Wu Guixian , Lin Xiaomai , Lin Ling , Pan Weijia
Published: July 2021

A phase II study of toripalimab plus anlotinib as maintenance therapy in extensive-stage small cell lung cancer

Background: Maintenance therapy is a promising therapeutic approach for extensive-stage small cell lung cancer (ES-SCLC), especially in light of the IMpower 133 trial (Horn NEJM 2018). The results of the E3501, SALUTE, and CALGB 30306 trials showed that in first-line treatment of ES-SCLC, bevacizumab combined with chemotherapy improved only progression-free survival (PFS) but not overall survival (OS). However, in the ALTER 1202 study, anlotinib used as a third- or further-line treatment in patients with ES-SCLC improved PFS and OS (Cheng WCLC 2018). Toripalimab is a novel PD-1 inhibitor that, when combined with anlotinib as maintenance therapy for ES-SCLC, may improve disease control.Methods: This is a phase 2, single-arm study of toripalimab plus anlotinib, a vascular endothelial growth factor receptor inhibitor, as maintenance therapy in adult patients with ES-SCLC following their completion of platinum-based first-line chemotherapy. Eligible patients must have measurable (RECIST v1.1) ES-SCLC, an ECOG performance status of 0 or 1, and are required to have shown complete response, partial response, or stable disease as per RECIST 1.1 following 4–6 cycles of platinum-based chemotherapy. Twenty participants will be enrolled to receive toripalimab (240 mg, IV, Q3W) + anlotinib (12 mg, oral, Q3W). Patients will be treated until the disease progresses, unacceptable toxicity occurs, or for up to 2 years. Prophylactic cranial irradiation will be permitted at the investigator's discretion. The primary endpoints are PFS and OS. Secondary endpoints include safety, objective response rate, disease control rate, and time to response. Exploratory endpoints include Tumor Mutational Burden (TMB) and PD-L1 protein expression, immune gene transcript expression (PD-1, PD-L1, CTLA-4, and others) ,and correlation of these endpoints with clinical responses and drug resistance. This study is currently open and accruing patients. Clinical trial information: NCT04363255. Research Sponsor: Shanghai Junshi Biosciences Co.

Citation Format: Dongqing Lv, Guixian Wu, Xiaomai Lin, Ling Lin, Weijia Pan. A phase II study of toripalimab plus anlotinib as maintenance therapy in extensive-stage small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT232.
Abstract LB005: High quality neoantigens are immunoedited in long term survivors of pancreatic cancer
Authors: Luksza Marta , Sethna Zachary , Rojas Luis , Soares Kevin , Elhanati Yuval , Lihm Jayon , Hoyos David , Kappagantula Rajya , Moore Alvin M. , Patterson Erin , Iacobuzio-Donahue Christine , Greenbaum Benjamin , Balachandran Vinod P.
Published: July 2021

Cancer immunoediting, a hallmark of cancer, predicts that lymphocytes recognize tumor-specific mutations (neoantigens) to kill immunogenic tumor cells and select less immunogenic clones to survive in immunocompetent hosts. Yet, though proven in mice, whether immunoediting governs how human tumors evolve naturally, and the principles of how the immune system edits tumors remain unclear. Here, we report that T cell rich tumors of rare long-term survivors of human pancreatic ductal adenocarcinoma longitudinally lose immunogenic features predicted by a fitness model based on immune recognition of high quality neoantigens. We find that compared to T cell poor tumors in short-term survivors, long-term survivors evolve less immunogenic recurrent tumors over 10 years with fewer clones, fewer neoantigens, and new neoantigens of markedly lower quality, to indicate that the immune system edits lower fitness clones with high-quality neoantigens. To explore if the immune system more broadly selects against non-self-like changes in host genomes, we define a minimal amino acid substitution distance sufficient for T cell receptors to discriminate self from non-self mutations. We find that both primary and recurrent tumors in long but not short-term survivors are enriched in self-like mutations, to suggest that the immune system depletes non-self-like mutations. Thus, we submit longitudinal evidence that the immune system edits neoantigens to sculpt recurrent human pancreatic ductal adenocarcinomas, a lethal tumor largely considered resistant to endogenous immune attack. Furthermore, we demonstrate that the neoantigen quality fitness model predicts how immune pressure changes tumor cell populations over time, with significant implications for cancer biology and immunotherapy. More broadly, our results argue that cancer immunoediting is a fundamental principle of how human cancers evolve in immunocompetent hosts.

Citation Format: Marta Luksza, Zachary Sethna, Luis Rojas, Kevin Soares, Yuval Elhanati, Jayon Lihm, David Hoyos, Rajya Kappagantula, Alvin M. Moore, Erin Patterson, Christine Iacobuzio-Donahue, Benjamin Greenbaum, Vinod P. Balachandran. High quality neoantigens are immunoedited in long term survivors of pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB005.
Abstract LB073: The growth inhibitory effect of paclitaxel on gefitinib-resistant non-small cell lung cancer (NSCLC) cells during the COVID-19 pandemic
Authors: Mohiuddin Md , Kimura Hideharu , Sone Takashi , Watanabe Satoshi , Matsuoka Hiroki , Saeki Keigo , Terada Nanao , Abo Miki , Kasahara Kazuo
Published: July 2021

Background: Coronavirus disease 2019 (COVID-19) has posed a great challenge for the treatment of cancer patients. COVID-19 presents as a severe respiratory infection in aging individuals, including lung cancer patients. COVID-19 may be linked to the progression of aggressive lung cancer. Conversely, the side effects of chemotherapy, such as chemotherapy resistance and the acceleration of cellular senescence could worsen COVID-19. Considering the above-mentioned facts, our present work aimed to investigate the role of paclitaxel (a chemotherapy drug) in the cell proliferation, apoptosis, and cellular senescence of gefitinib-resistant NSCLC cells (PC9-MET) and to reveal the underlying mechanisms. Methods: PC9-MET cells were treated with paclitaxel for 72 h and were then evaluated by a cell viability assay, DAPI staining, Giemsa staining, apoptosis assay, ROS assay, SA-β-Gal staining, TUNEL assay and Western blotting.Results: Our results revealed that paclitaxel significantly reduced the viability of PC9-MET cells and induced morphological signs of apoptosis. The apoptotic effects of paclitaxel were observed by increased levels of cleaved caspase-3, cleaved caspase-9 and cleaved PARP. Additionally, paclitaxel increased ROS production, leading to DNA damage. Importantly, paclitaxel eliminated cellular senescence, which was observed by SA-β-Gal staining.Conclusion: In light of these findings, paclitaxel could be a promising anticancer drug and could offer a new therapeutic strategy for gefitinib-resistant NSCLC during the COVID-19 pandemic.

Citation Format: Md Mohiuddin, Hideharu Kimura, Takashi Sone, Satoshi Watanabe, Hiroki Matsuoka, Keigo Saeki, Nanao Terada, Miki Abo, Kazuo Kasahara. The growth inhibitory effect of paclitaxel on gefitinib-resistant non-small cell lung cancer (NSCLC) cells during the COVID-19 pandemic [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB073.