bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 410: Quantification and downstream analysis of circulating tumor cells isolated using CapioCyteTM liquid biopsy
Authors: Poellmann Michael J. , Bu Jiyoon , Moon Dominic , Wagner Kyle , Wang Andrew Z. , Hong Seungpyo
Published: August 2019

Background: Circulating tumor cells (CTCs) have great potential as biomarkers for the diagnosis and prognosis of many cancers. The CapioCyteTM chip isolates live CTCs through a unique combination of biomimetic cell rolling and nanoparticle-mediated multivalent immunorecognition. Recently-published work reported the highly sensitive and specific CTC capture from 24 patients in a pilot study [Myung et al., Clinical Cancer Research 2018, 24(11):2439-2547]. Here, we report results from additional cohorts of patients and demonstrate downstream analysis of captured CTCs.

Methods: Peripheral blood samples were collected from patients undergoing radiotherapy (RT) (n=12; oligometastic n = 5, head and neck cancer n = 1, non small cell lung cancer n = 2, prostate cancer n = 3, cervical cancer n = 1) or immunotherapy (n=4). Samples were processed the next day by CapioCyteTM chips designed for the immunoisolation cells expressing epithelial cell adhesion molecule (EpCAM), human epidermal growth factor-2 (HER-2), and epidermal growth factor receptor (EGFR). Captured CTCs were identified by immunocytochemistry as containing round nuclei, positive expression of cytokeratin, and negative expression of CD45. Select samples were recovered from the capture surface and submitted for single cell gene expression assays (RNASeq) using 10X Genomics Chromium barcoding and Illumina next-generation sequencing.

Results: Immunocytochemical staining identified CTCs in all pre-treatment blood samples from patients undergoing RT (mean 95 CTC/ml whole blood, SE 54, range 4-680) and immunotherapy (mean 70 CTC/ml whole blood, SE 16, range 39-104). CTC counts decreased with time points collected during and post-treatment, consistent with other measures of treatment progress. Single cell RNASeq confirmed the presence of tumor-derived cells in select samples and, importantly, demonstrated the ability to conduct downstream analysis of CTCs isolated on the CapioCyteTM chip.

Conclusions: The CapioCyteTM chip effectively captures CTCs for quantification and downstream analysis requiring viable cells such as RNASeq. The liquid biopsy technology has great potential to contribute to diagnosis and personalized treatment of cancer.

Citation Format: Michael J. Poellmann, Jiyoon Bu, Dominic Moon, Kyle Wagner, Andrew Z. Wang, Seungpyo Hong. Quantification and downstream analysis of circulating tumor cells isolated using CapioCyteTM liquid biopsy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 410.
Abstract 4102: DNA methylation and repressive histones in the promoters of immune checkpoints in tumor tissues and peripheral blood of breast and colorectal cancer patients
Authors: Elkord Eyad , Nair Varun Sasidharan , Toor Salman M.
Published: August 2019

Higher expression of immune checkpoints in tumor microenvironment plays significant roles in inhibiting anti-tumor immunity, which is associated with poor prognosis and progression of cancer patients. Major epigenetic modifications in both DNA and histone could be involved in upregulation of immune checkpoints (ICs) in cancer. We investigated transcriptomic expression of different ICs and some ligands including PD-L1 and galectin-9 in the tumor microenvironment (TME) and in circulation of primary breast cancer (PBC) and colorectal cancer (CRC) patients. We found that transcriptomic expressions of PD-1, CTLA-4, TIM-3 and LAG-3 in PBC and PD-1, CTLA-4, TIM-3, TIGIT, PD-L1 and galectin-9 in CRC were significantly upregulated in tumor tissues (TT), compared with normal tissues (NT). Additionally, expressions of TIM-3, TIGIT, and PD-L1 were significantly upregulated, while LAG-3 was downregulated in peripheral blood of both PBC and CRC patients. We then investigated the epigenetic modifications beyond this upregulation of immune checkpoint genes. Interestingly, we found that CpG islands in the promoters of PD-1, CTLA-4 and TIM-3 in PBC, and CTLA-4 and TIGIT in CRC patients were significantly hypomethylated in tumor compared with normal tissues. Notably, CpGs in PD-L1 promoter were completely hypomethylated in PBC and CRC in both TT and NT. In addition, PD-L1 was hypomethylated in in peripheral blood of both PBC and CRC patients, while TIGIT was hypomethylated only in circulation of CRC patients, compared with healthy donors. Next, we checked the abundance of repressive histones (H3K9me3 and H3K27me3) in the promoter regions of ICs/ligands. We found that in PBC TT, distribution of both H3K9me3 and H3K27me3 was lower in the promoters of PD-1, CTLA-4 and LAG-3, while distribution of only H3K27me3 was lower in TIM-3 promoter, compared with NT. Furthermore, in CRC TT, the distribution of H3K9me3 was lower in PD-1 and TIGIT promoters, and H3K27me3 was lower in CTLA-4 promoter, while both H3K9me3 and H3K27me3 were lower in TIM-3 promoter, compared with NT. Our data demonstrate that both DNA methylation and repressive histones are involved in upregulation of ICs and their ligands in the tumor microenvironment and peripheral blood of breast and colorectal cancer patients. These epigenetic modifications could be useful as diagnostic/prognostic biomarkers and/or therapeutic targets in breast and colorectal cancers.

Citation Format: Eyad Elkord, Varun Sasidharan Nair, Salman M. Toor. DNA methylation and repressive histones in the promoters of immune checkpoints in tumor tissues and peripheral blood of breast and colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4102.
Abstract 4113: Quantitative cell-based bioassays to advance immunotherapy programs targeting immune checkpoint receptors
Authors: Grailer Jamison , Gilden Julia , Stecha Pete , Garvin Denise , Wang Jun , Beck Michael , Hartnett Jim , Krishnan Gopal , Fan Frank , Cong Mei , Cheng Zhi-jie Jey
Published: August 2019

The human immune system is comprised of a complex network of immune checkpoint receptors that are promising new immunotherapy targets for the treatment of a variety of cancers and autoimmune disorders. The Nobel prize for Medicine in 2018 was awarded for seminal studies on the role of immune checkpoint targets in T cell activation and furthermore, combining different strategies to release the brakes on the immune system with the aim of eliminating tumor cells even more efficiently. Immunotherapies designed to block co-inhibitory receptors (e.g. PD-1, CTLA-4, TIGIT) are showing unprecedented efficacy in the treatment of cancer. However, not all patients and tumor types respond to this approach. This has resulted in broadening of immunotherapy research programs to target additional co-inhibitory (e.g. LAG-3, TIM-3) and co-stimulatory (e.g. 4-1BB, GITR, OX40, ICOS) receptors individually and in combination.

A major challenge in the development of antibody-based biologics is access to quantitative and reproducible functional bioassays. Existing methods rely on primary cells and measurement of complex functional endpoints. These assays are cumbersome, highly variable and fail to yield data required for drug development in a quality-controlled environment. To address this need, we have developed a suite of cell-based functional bioassays to interrogate modulation of immune checkpoint receptors individually (e.g. PD-1, LAG-3, TIM-3, GITR, 4-1BB) and in combination (e.g. PD-1+CTLA-4, PD-1+LAG-3). These assays consist of stable cell lines that express luciferase reporters driven by response elements under the precise control of mechanistically relevant intracellular signals. Thus, the bioassays reflect mechanisms of action for the drug candidates designed for each immune checkpoint receptor and demonstrate high specificity, sensitivity and reproducibility. Here we describe the application of MoA-based immune checkpoint receptor bioassays as tools for biologics drug discovery, development, potency and stability studies.

Citation Format: Jamison Grailer, Julia Gilden, Pete Stecha, Denise Garvin, Jun Wang, Michael Beck, Jim Hartnett, Gopal Krishnan, Frank Fan, Mei Cong, Zhi-jie Jey Cheng. Quantitative cell-based bioassays to advance immunotherapy programs targeting immune checkpoint receptors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4113.
Abstract 4116: Immune cell checkpoint profiling of solid tumors by multiplex immunofluorescence
Authors: Finan Amanda , Goulange Nicolas , Motte Manon , Tliba Maroua , Mace Alexandra , Coton Jean-Philippe , Lazzaro Domenico , Burrer Renaud
Published: August 2019

Immune checkpoint proteins are important regulators in self-tolerance. However, these same molecules also allow cancer cells to evade immune destruction. Checkpoint inhibitor (CKI) blockade therapies that aim at restoring antitumoral immunity have resulted in long-lasting remission in patients with cancers that were previously seen as incurable. However, only a fraction of the patients respond to these treatments. Research is currently focusing on identifying biomarkers that can predict a response to CKI therapies and stratify patient populations. As it is likely that several CKI need to be targeted at once to restore immune responses, numerous clinical trials associating more than one CKI are under evaluation. We have developed a multiplex immunohistochemistry panel, validated by in-depth image analysis, for immune cell checkpoint profiling. The base of the panel consists of CD3/CD8/PD-1/PD-L1 with the capability of adding additional targets including other immune checkpoint (e.g. TIGIT, SIRPα, CTLA-4) or tumor markers. Here we present our validation assay which uses the base panel and the ability to interchange the additional targets. Assay conditions for the individual biomarkers, including antigen retrieval, antibody concentration, panel position, and efficiency of stripping, are optimized. Simplex protocols are analyzed to ensure accuracy and specificity of the staining, success of stripping, and a balance of signal intensities. Validation includes the comparison of staining (% positive cells or % positive area) between a reference protocol and the position of interest. Multiplex optimization consists of staining serial, single stained slides of the individual biomarkers and the multiplex slide in parallel. The staining concordance (% positive cells) is evaluated with imaging software. Repeatability and robustness of the panels are validated by image analysis. This technique gives clinicians the potential to determine candidate patients for CKI single or double therapies and their progress during treatment. The established, rigorous workflow that we have developed allows our customers to adapt the panels to their needs and to have the highest confidence in the consequent images and results related to the profiling of immune cell checkpoints in solid tumors.

Citation Format: Amanda Finan, Nicolas Goulange, Manon Motte, Maroua Tliba, Alexandra Mace, Jean-Philippe Coton, Domenico Lazzaro, Renaud Burrer. Immune cell checkpoint profiling of solid tumors by multiplex immunofluorescence [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4116.
Abstract 4122: The regulatory mechanism of PD-L1 level through ER-associated degradation
Authors: Cha Jong-Ho , Yang Wen-Hao , Xia Weiya , Wei Yongkun , Chan Li-Chuan , Li Chia-Wei , Lee Heng-Huan , Hung Mien-Chie
Published: August 2019

Programmed death ligand-1 (PD-L1) is an important immune checkpoint molecule that allows cancer cells to evade immune surveillance. Further, the PD-L1 level is relatively higher in tumor tissues compared to normal tissues. Thus, the PD-L1/PD-1 axis has served as primary target for cancer immunotherapy. However, the regulatory mechanisms of PD-L1 level are not fully understood.

Here, we demonstrated that the ER-associated degradation (ERAD) mechanism of PD-L1 through cross-talking between phosphorylation and glycosylation. We discover that AMP-activated protein kinase (AMPK) activated by metformin directly binds with PD-L1 in the ER lumen and phosphorylates Ser 195 of PD-L1. The Ser 195 phosphorylation induces abnormal mannose-rich glycan structures of PD-L1 through excessive ER trimming process. PD-L1 with abnormal glycan structures is occupied by ER quality check components in the ER and finally degraded through ERAD pathway.

We provide new insights to understand cancer immune checkpoints by identifying a new regulatory mechanism of PD-L1 and these findings can be used to improve the efficacy of previous cancer immunotherapy for the PD-L / PD-1 axis.

Citation Format: Jong-Ho Cha, Wen-Hao Yang, Weiya Xia, Yongkun Wei, Li-Chuan Chan, Chia-Wei Li, Heng-Huan Lee, Mien-Chie Hung. The regulatory mechanism of PD-L1 level through ER-associated degradation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4122.
Abstract 4123: Clinical significance and the difference between programmed death-1 ligand-1 and ligand-2 in patients with esophageal cancer
Authors: Okadome Kazuo , Baba Yoshifumi , Yagi Taisuke , Kiyozumi Yuki , Eto Kojiro , Hiyoshi Yukiharu , Nagai Yohei , Ishimoto Takatsugu , Iwatsuki Masaaki , Iwagami Shiro , Miyamoto Yuji , Yoshida Naoya , Baba Hideo
Published: August 2019

Background: Immunotherapies targeting the PD-1/PD-L1 pathway have emerged as promising therapeutic strategies for many cancers. PD-L1 and PD-L2 are ligands of PD-1 on T-cells and prevent T-cells activation and proliferation. There have been reported that PD-L1 and PD-L2 are expressed on not only antigen-presenting cells but also some types of tumors. Clinical and prognostic features of the PD-L1 have been widely reported for many types of cancers but those of PD-L2 remain unclear in esophageal cancer. The aim of this study was to analyze the clinical significance and the difference between PD-L1 and PD-L2 in esophageal cancer.

Methods: Using a database of 437 curatively resected esophageal cancer from April 2005 to March 2016, we evaluated PD-L1 and PD-L2 expression in tumor cells by immunohistochemical staining and analyzed the association between those with clinicopathological features. Double immunohistochemical staining for PD-L1 and PD-L2 was performed to confirm the localization of each positive cell.

Results: Out of 437 cases of esophageal cancer, 69 cases (15.8%) showed PD-L1 positive and 71 cases (16.2%) showed PD-L2 positive expression. There was no significant relationship between PD-L1 and PD-L2 positive cases (p=0.18). In both PD-L1 and PD-L2 positive cases, double immunohistochemical staining for PD-L1 and PD-L2 showed that there was a heterogeneity for PD-L1 and PD-L2 positive tumor cell. PD-L1 positive cases were significantly associated with tobacco use (p=0.013), pathological stage (p=0.001), and preoperative therapy present cases (p=0.015). In the other hand, PD-L2 positive cases were significantly associated with younger age (p=0.029). Thus PD-L1 and PD-L2 patient characteristics were likely different. Overall survival rates of the patients with PD-L1 or PD-L2 positive were significantly worse than those with PD-L1 or PD-L2 negative (p=0.009 and p=0.013, respectively).

Conclusion: There was no significant relationship between PD-L1 and PD-L2 expression, and patient characteristics of those were different in patients with esophageal cancer. But both PD-L1 and PD-L2 expression were significantly associated with prognosis, supporting their roles as prognostic biomarkers.

Citation Format: Kazuo Okadome, Yoshifumi Baba, Taisuke Yagi, Yuki Kiyozumi, Kojiro Eto, Yukiharu Hiyoshi, Yohei Nagai, Takatsugu Ishimoto, Masaaki Iwatsuki, Shiro Iwagami, Yuji Miyamoto, Naoya Yoshida, Hideo Baba. Clinical significance and the difference between programmed death-1 ligand-1 and ligand-2 in patients with esophageal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4123.
Abstract 4127: RX-5902 exhibits direct and immunomodulatory anti-tumor activities in melanoma PDX models
Authors: Eisen Andrew
Published: August 2019

Background: Nuclear β-catenin promotes deleterious processes in tumors and their microenvironment. Diminishing nuclear β-catenin attenuates these oncogenic processes. RX-5902 is an oral, small molecule inhibitor of β-catenin nuclear translocation mediated by phosphorylated p68 (DDX5). RX-5902 exhibits potent anti-cancer activity in many cancer cell lines, xenograft models in immunodeficient mice and immune competent mice and in patients. This study examines the relative contribution and context of the direct and immunomodulatory effects on the anti-tumor activities of RX-5902.

Methods: Four patient-derived melanoma xenograft models were implanted into either immunodeficient nude mice or NOG mice “humanized” with HLA unmatched CD34+ stem cells with average humanization of 36%. The PDX models were derived from 2 tumors that were clinically unresponsive to an anti-PD-1 agent and 2 tumors obtained prior to any immune treatment. In each category one tumor had BRAF WT and one a V600E mutation. Mice were randomized to receive either vehicle or RX-5902 at 5, 15 or 50 mg/kg po QDx5/Off x2 when implanted tumors reached 100-120 mm3 and began treatment when tumors reached 200mm3. Treatment lasted for 28 days and animals were observed for an additional 14 off therapy.

Results: The tumor growth inhibition data at 50 mg/kg is found in the table below. There was evidence of an immune contribution to the TGI in those tumors derived from subjects who did not benefit from I/O (Nivolumab) therapy. In each category the response was greater in tumors with WT BRAF.

Conclusion: RX-5902 provided greater TGI in the two melanoma PDX models derived from subjects who were resistant to I/O therapy compared to the models from I/O naïve subjects and, regardless, is greater in BRAF WT vs mutant tumors. The RX-5902 immune-mediated anti-tumoral activity may benefit the majority of melanoma subjects with limited response to BRAF-directed and/or I/O therapy.

Citation Format: Andrew Eisen. RX-5902 exhibits direct and immunomodulatory anti-tumor activities in melanoma PDX models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4127.
Abstract 4131: Overcoming aryl hydrocarbon receptor mediated tumor immunosuppression
Authors: Tchaicha Jeremy , Coma Silvia , Walsh Meghan , Cavanaugh Jill , Sanchez-Martin Marta , Zhang X. Michelle , Castro Alfredo , Ecsedy Jeff , Manfredi Mark , McGovern Karen
Published: August 2019

Checkpoint inhibitors (CPIs) have become the cornerstone of immune-based oncology therapy; still many cancer patients do not benefit from these agents. Resistance to checkpoint inhibitors is due in part to the presence of immunosuppressive molecules which prevent immune activation despite T cell checkpoint inhibition. Aryl Hydrocarbon Receptor (AHR) is a transcription factor that mediates the immune response in multiple innate and adaptive immune cells subsequent to binding of a diverse set of endogenous and exogenous ligands. One such AHR agonist is kynurenine. Kynurenine, metabolized from tryptophan by indoleamine-pyrrole 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase 2 (TDO2), binds to AHR and leads to a net immunosuppressive tumor microenvironment.

Given that kynurenine can be synthesized by both IDO1 and TDO2 and that AHR is activated by endogenous ligands other than kynurenine, AHR inhibition provides a novel approach to reverse immunosuppression in a broad range of tumor types. We demonstrated that AHR antagonism affects multiple immune cell types and can lead to pro-inflammatory phenotypes in human T cells and myeloid cells in vitro and in murine tumor models. AHR antagonism inhibits growth in the B16-IDO, CT26 and MC38 models and reverses the immunosuppressive microenvironment as indicated by changes in T cell and myeloid cell populations. Immune signature changes characterized via Nanostring in multiple tumor models treated with AHR antagonists were also assessed.

Oral dosing of AHR antagonists led to tumor growth inhibition as a single agent and increased anti-tumor activity when combined with checkpoint inhibitors. In addition, beneficial anti-tumor activity occurred with AHR antagonists combined with chemotherapy or with radiation therapy in syngeneic mouse tumor models. Our data indicate that reversing AHR-mediated immune suppression in the tumor microenvironment drives anti-tumor activity alone and in combination with other therapeutic modalities.

Overall, our data demonstrates that AHR is an attractive target for reversing immune suppression in tumors. Therefore, we are developing AHR antagonists and translational insights to treat patients most likely to benefit from this approach.

Citation Format: Jeremy Tchaicha, Silvia Coma, Meghan Walsh, Jill Cavanaugh, Marta Sanchez-Martin, X. Michelle Zhang, Alfredo Castro, Jeff Ecsedy, Mark Manfredi, Karen McGovern. Overcoming aryl hydrocarbon receptor mediated tumor immunosuppression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4131.
Abstract 4135: Novel dual A2A A2B adenosine receptor antagonists for cancer immunotherapy: in vitro and in vivo characterization
Authors: Galezowski Michal , Węgrzyn Paulina , Bobowska Aneta , Dziedzic Katarzyna , Szeremeta-Spisak Joanna , Nowogrodzki Marcin , Satala Grzegorz , Obara Alicja , Lozinska-Raj Iwona , Dudek Marcelina , Janiga Anita , Reus Jacek , Wronowski Marek , Zastawna Magdalena , Statkiewicz Grzegorz , Rogacki Maciej , Ziembik Magdalena , Grycuk Karolina , Soukou Foteini , Michalik Kinga , Adamus Agnieszka , Wiatrowska Karolina , Lewandowska Natalia , Golas Aniela , Haberkiewicz Olga , Porter Rod , Brzozka Krzysztof , Nowak Mateusz
Published: August 2019

Adenosine is important messenger molecule that is involved in signal transmission in central nervous, cardiovascular and immunological systems. The immunosuppressive role of adenosine attract attention of many researchers recently and reversal of that effect is addressed by several different approaches i.e.: inhibition of enzymes that are producing the adenosine in tumor microenvironment like CD39 and CD73 but also the antagonization of adenosine receptors mainly A2A and A2B subtypes. Here we present a novel series of unsurmountable, dual A2A/A2B antagonists that retain its nanomolar potency in tumor-like adenosine-rich environment. This advantageous profile comes mainly from long residence time in adenosine receptors which transfers into high receptor occupancy even after full clearance of the compound from plasma. We are demonstrating how our inhibitors restore adenosine depleted immune functionality in the series of functional in vitro assays in primary cells. This includes the cytokine release by activated CD4+ and CD8+ human T-lymphocytes (driven by A2A) and dendritic cells (driven by A2B). Most importantly presented compounds show improved in vivo pharmacological profile in comparison to adenosine inhibitors currently tested in clinical trials manifested by high inhibition of CREB phosphorylation in mouse model.

Citation Format: Michal Galezowski, Paulina Węgrzyn, Aneta Bobowska, Katarzyna Dziedzic, Joanna Szeremeta-Spisak, Marcin Nowogrodzki, Grzegorz Satala, Alicja Obara, Iwona Lozinska-Raj, Marcelina Dudek, Anita Janiga, Jacek Reus, Marek Wronowski, Magdalena Zastawna, Grzegorz Statkiewicz, Maciej Rogacki, Magdalena Ziembik, Karolina Grycuk, Foteini Soukou, Kinga Michalik, Agnieszka Adamus, Karolina Wiatrowska, Natalia Lewandowska, Aniela Golas, Olga Haberkiewicz, Rod Porter, Krzysztof Brzozka, Mateusz Nowak. Novel dual A2A A2B adenosine receptor antagonists for cancer immunotherapy: in vitro and in vivo characterization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4135.
Abstract 4166: Hereditary cancer syndromes in Guatemalan population
Authors: Carranza Claudia L. , Guerra Mariela , Osorio Claudia , Zamora Vanessa , Herrera Vivian , Gil Jose , Alvarez Luis
Published: August 2019

BACKGROUND The majority of cancer are sporadic, only around 5 % are considered hereditary. Although it is a low percentage, the study of these cancers are of vital importance, since they require a special clinical monitoring and management. These kind of cancers are caused by the presence of an inherited gene mutation, which increase the risk of developing a tumor. The mutations associated with these tumors are germline mutations, this means that are present in all the patient's cells, including the egg cell an sperm; this is the reason why this type of cancer can transmit to the future generations. There are many syndromes that increase the risk of hereditary cancer development, the most frequent syndromes are: Familial Breast and Ovarian cancer (BRCA1 and BRCA2 gene mutations), Lynch syndrome (MSH2, MLH1, MSH6 and PMS2 mutations), Li-Fraumeni syndrome (TP53 gene mutations) and Familial adenomatous polyposis (APC gene mutations). The aim of this study is to screen the most common hereditary cancer syndromes in Guatemalan population.

METHODS We analyzed 199 blood samples of patients with different types of tumors. We extracted DNA from the samples and then analyzed the gene mutations by next generation sequencing.

RESULTS AND DISCUSSION We have included in the present study, 93 cases with Familial Breast cancer and 106 with another type of tumors. Of all cases, we have found 17 cases with hereditary cancer syndromes (8%). The most frequent is the Breast and Ovarian hereditary syndrome caused by BRCA1 and BRCA2 (12 patients). The other hereditary cancer syndromes are shown in Table 1. The detection of this germline mutations, have a large impact in the familial cases, because these patients and their families could be monitored and evaluated more frequently. This is the first report of these syndromes in our population.

CONCLUSION We reported 6 different syndromes and 17 cases, related to hereditary cancer risk and predisposition in Guatemalan population.

Frequency of hereditary cancer syndromesSYNDROMENUMBER OF PATIENTSCANCER TYPEAGESEXGENE MUTATIONBreast and ovarian hereditary syndrome7Breast cancer29-48FBRCA1Breast and ovarian hereditary syndrome5Breast cancer29-71FBRCA2Lynch syndrome1Breast cancer80FMSH6Li-Fraumeni syndrome1Breast cancer58FTP53Breast hereditary cancer1Breast cancer57FCDH1Peutz-Jeghers syndrome1Pancreatic cancer15FSTK11Familial adenomatous polyposis1Colorectal cancer13MAPC

Citation Format: Claudia L. Carranza, Mariela Guerra, Claudia Osorio, Vanessa Zamora, Vivian Herrera, Jose Gil, Luis Alvarez. Hereditary cancer syndromes in Guatemalan population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4166.
Abstract 4174: Familiality of ovarian cancer histotypes in the Utah Population Database
Authors: Barnard Mollie E. , Camp Nicola J. , Doherty Jennifer A.
Published: August 2019

Introduction: Ovarian cancer is a heterogeneous disease; each histotype has distinct molecular origins, risk factors and outcomes. While it is well established that ovarian cancer has a familial risk component, the familiality of ovarian cancer histotypes has not been well described. The Utah Population Database (UPDB) captures over 10 million individuals, including more than 5 million with a minimum of three generations of genealogy data. By linking records from the UPDB to the Utah Cancer Registry (UCR) and other statewide data sources, we sought to describe the familiality of ovarian cancer histotypes.

Methods: Our study includes all ovarian cancer cases in the UPDB and leverages clinical data reported to UCR for the case histotypes. Cases were matched to controls on age, birth cohort and at least three generations of UPDB data versus not. We quantified familiality by comparing the odds of ovarian cancer occurrence among family members of cases to the odds of ovarian cancer among family members of matched controls. We calculated odds ratios for first-degree relatives, second-degree relatives, and first cousins.

Results: As of September 2018, the UPDB included 3,989 ovarian cancer cases. We observed an increased risk of epithelial ovarian cancer among first-degree relatives (OR=1.62, 95%CI=1.36-1.93), second-degree relatives (OR=1.53, 95%CI=1.34-1.74), and first cousins (OR=1.38, 95%CI=1.26-1.53) of ovarian cancer cases. When we analyzed epithelial ovarian cancers by histotype, familiality was most evident for high-grade serous, mucinous, and unclassified cancers. For example, we observed a 1.62-fold increased odds (95%CI=1.14-2.29) of high-grade serous ovarian cancer among the first-degree relatives of high-grade serous cases, and a 5.59-fold increased odds (95%CI=2.09-14.92) of mucinous ovarian cancer among first-degree relatives of mucinous ovarian cancer cases. Familiality patterns were less clear among endometrioid and clear cell cases.

Conclusions: The UPDB has the potential to contribute greatly to family-based studies of the genetics of ovarian cancer histotypes. Despite the possible variations in quality of histotype data across generations, preliminary results suggest some histotypes may be particularly familial and good candidates for gene mapping studies. Work is ongoing to refine the histotype assignments for cases by performing pathology review using the 2014 World Health Organization guidelines. Analyses are also in progress to stratify analyses by BRCA mutation status, and to consider the potential for shared familiality across ovarian cancer histotypes and with cancers at other sites.

Citation Format: Mollie E. Barnard, Nicola J. Camp, Jennifer A. Doherty. Familiality of ovarian cancer histotypes in the Utah Population Database [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4174.
Abstract 418: Ex vivoisolation and culture of circulating tumor cells using microfluidics chip
Authors: Zhang Huirong , Zhao Pan , Wu Han , Zou Chang
Published: August 2019

Background: Circulating tumor cells (CTCs) are the tumor cells shed from primary tumor, which enter the bloodstream and travel to distant anatomic sites to form metastasis. CTCs have been identified as blood-based biomarkers to guide cancer diagnosis and prognosis in many reports. The huge challenge which limits the clinical utility of CTCs, especially in early stage cancer patients, is the rarity. Specifically, there are only 1-10 CTCs in one milliliter of whole blood.

Methods: A microfluidic CTC capture device was used for capture and analysis of CTCs from gastric cancer patients. The patients’ samples were referred to the regulation of ethnic commission of Shenzhen People’s Hospital and informed parental consent for the study. CTCs were collected by cells adherent culture using the CCC medium. Immunofluorescence, karyotyping and mude mouse tumorigenesis were used to verify the CTCs.

Results: A epithelial phenotype cell cluster which named S-CTC came out in the 24-well plate after 8 days. S-CTC cells can steadily formed clones and showed stem-cell like properties. Positive rate of CD133 were reached to 4.7% which demonstrated by flow cytometry. Immunofluorescence identification of S-CTC were DAPI-positive, Cytokeratin-positive, and CD45-negative. The karyotyping results indicated that the chromosomes were aneuploidthe, the chromosome number of S-CTC varied from 55 to 63. Also S-CTC presented a larger nuclear/cytoplasmic ratio and limitless replicative potential. Furthermore, the S-CTC had huge sphere formation ability, the tumorigenesis of S-CTC cells can be happened by xenografting in immunodeficient mice.

Conclusion: A cell S-CTC were successfully isolated and cultured by the technology microfluidic chip. S-CTC was identified using a series of analysis and can be confirmed to be the tumor cell, which would be provide more drug sensitivity information of the patient and open up novel avenues towards the understanding of gastric cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Huirong Zhang, Pan Zhao, Han Wu, Chang Zou. Ex vivoisolation and culture of circulating tumor cells using microfluidics chip [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 418.
Abstract 4192: Increasing incidence of EBV-related nasopharyngeal carcinoma in the United States
Authors: Argirion Ilona , Zarins Katie R. , Ruterbusch Julie J. , Vatanasapt Patravoot , Sriplung Hutcha , Seymour Erlene K. , Rozek Laura S.
Published: August 2019

Purpose: Incidence of nasopharyngeal carcinoma (NPC) is highly geographically variable and historically rare in the US. While etiological factors differ by histological subtype, Epstein-Barr virus (EBV) is generally accepted as the primary risk factor for non-keratinizing NPC. In light of the changing epidemiology of HPV-associated oropharyngeal cancer, it is important to evaluate temporal incidence of NPC in the US.

Methods: Incidence and survival data from 1973-2015 were obtained from the Surveillance, Epidemiology and End Results (SEER) Program. Stratified analyses were conducted to assess temporal trends in NPC by histological subtype, sex and race. The data were analyzed using SAS 9.4 and Joinpoint Regression Software to determine age-adjusted incidence rates, trends in annual percent change (APC) as well as calculate 5-year relative survival estimates and Kaplan-Meier curves.

Results: Although overall NPC incidence is decreasing in the US, the non-keratinizing differentiated subtype appears to be starkly increasing with an APC of approximately 4% among white males (95%CI: 2.5, 5.2), white females (95%CI: 1.9, 6.2), and black males (95%CI: 2.0, 5.7), 2.7% among black females (95%CI: 0.8, 4.6) and 1.8% among women of other race (95%CI: 0.4, 3.3). When compared to other histological subtypes, patients with keratinizing squamous cell carcinoma had the worst survival (log rank p<0.001). Additional survival disparities were noted, with black males having consistently poorer survival across all histological subtypes, and those individuals in the “other” race category, particularly females, experiencing the highest 5-year relative survival estimates.

Conclusions: Although NPC remains relatively rare in the overall US population, there is evidence to suggest that the EBV-related differentiated subtype is increasing across all genders and races.

Citation Format: Ilona Argirion, Katie R. Zarins, Julie J. Ruterbusch, Patravoot Vatanasapt, Hutcha Sriplung, Erlene K. Seymour, Laura S. Rozek. Increasing incidence of EBV-related nasopharyngeal carcinoma in the United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4192.
Abstract 4201: Patient-level predictors and hysterectomies among women with autoimmune diseases
Authors: Bahrani-Mostafavi Zahra , Huber Larissa R.
Published: August 2019

Introduction: Hysterectomy is the second most common surgical procedure performed among reproductive aged women. The primary reason for hysterectomy among women 35-54 years is uterine fibroids and for older women is uterine prolapse or gynecologic (GYN) cancer. According to the National Center for Health Statistics, an estimated 600,000 hysterectomies are performed annually in the U.S. with an annual cost of $5 billion, which makes hysterectomy a major public health concern. Autoimmune diseases (AD) are among the top ten leading causes of death among U.S. women age 65 and under. This high mortality rate among women with AD has been linked to cancer and other causes. Considering hysterectomy procedures as are invasive and costly procedures, a comprehensive study to investigate the association between patient-level predictors and hysterectomy procedures among AD patients in the U.S. is imperative.

Methods: 2007-2013 data from Florida State Inpatient samples of the Healthcare Cost and Utilization Project were used. The study population (n=699,280) was restricted to women who had any AD. The outcome variable was performance of hysterectomy, identified by CPT codes. Patient-level factors including race/ethnicity, age, insurance type, income level, and other comorbidities were analyzed as explanatory variables. Logistic regression analyses were used to identify independent predictors of hysterectomy procedures.

Results: Among AD subjects, the highest rate of hysterectomy was in Caucasian women (64.64%) and the lowest rate was in minorities other than Black and Hispanic women (3.0%). The odds of hysterectomies are were increased in older women who were older (0.74, 0.70-0.78), women, black (1.45, 1.36-1.54) women, have had private insurance (2.30, 2.14-2.45), and are fromhad lower income levels (1.10, 1.02-1.19), and had with more comorbid conditions, specifically GYN cancer.

Discussion: GYN complications may lead to hysterectomy, and ADs are major diseases among women. Because of the high prevalence of AD among women, more elucidation on the association between hysterectomy procedures and AD is essential for GYN complications management. Any unique combinations of characteristics that describe patients at risk for hysterectomy among AD patients could be used as a potential risk assessment for better management of GYN complications, and in particular GYN cancer.

Citation Format: Zahra Bahrani-Mostafavi, Larissa R. Huber. Patient-level predictors and hysterectomies among women with autoimmune diseases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4201.
Abstract 4205: Pan-cancer molecular study of disparities among African Americans
Authors: Lara Olivia D. , Wang Ying , Hu Wei , Zhang Lin , Rauh-Hain Alejandro , Sood Anil
Published: August 2019

Objective: Several factors have been proposed to contribute to racial disparities in gynecologic cancers, however there are no comprehensive studies that have investigated inherent molecular features that may be racially unique. Our objective was to perform a pan-cancer clinical and molecular analysis of African-Americans (AA) and European American (EA) patients.

Methods: We performed cross-platform analyses utilizing cancer registry and molecular databases [Surveillance, Epidemiology and End Results (SEER) and The Cancer Genome Atlas (TCGA)] to evaluate differences in AA vs EA patients. To characterize genetic ancestry we utilized the recently established The Cancer Genetic Ancestry Atlas (TCGAA). We further evaluated epigenetic modifications through non-coding RNA expression in these tumors.

Results: A total of 2,045,500 patients (87.5% EA, 12.5% AA) with 64 primary tumor types were evaluated using SEER to evaluate clinical outcome differences. Compared to white race, AA race had higher rate of death in 45 cancer types (HR>1.0, CI 1.00-5.23). 19 cancer types were then identified to have the largest differences in overall survival (HR>1.2). Utilizing TCGA, we analyzed molecular data of 7028 tumors (88.9% EA, 10.9% AA) having miRSeq data and genetic ancestry data. We identified differentially expressed miRNA’s in five cancer types: breast invasive (300 miRs, p<0.068, FDR<0.1), renal cell (408 miRs, p<0.205, FDR<0.1), prostate (102 miRs, p<2.68e-01, FDR<0.1), thyroid (63 miRs, p<1.28e-.02, FDR<0.1), and uterine corpus endometrial (177 miRs, p<8.18e-02, FDR<0.1) carcinomas. Differentially expressed miRs among all cancer types were associated with canonical pathways of cancer drug resistance by drug efflux, altered T- cell function, and regulation of epithelial-mesenchymal transition using Ingenuity Pathway Analysis (IPA) software. We identified miR-130, miR-180, miR-146, and miR-8 as commonly dysregulated miRs in these cancer types which may represent a molecular signature unique to African Americans.

Conclusions: Our results identify molecular and genetic features unique to African Americans that may contribute to worse survival outcomes. While the cause of cancer disparities is multifactorial, a focus on molecular signatures unique to AA may identify actionable molecular abnormalities.

Note: This abstract was not presented at the meeting.

Citation Format: Olivia D. Lara, Ying Wang, Wei Hu, Lin Zhang, Alejandro Rauh-Hain, Anil Sood. Pan-cancer molecular study of disparities among African Americans [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4205.
Abstract 4232: Spatially constrained tumor growth affects the patterns of clonal selection and neutral drift in cancer genomic data
Authors: Chkhaidze Kate , Heide Timon , Werner Benjamin , Williams Marc J. , Huang Weini , Caravagna Giulio , Baker Ann-Marie , Graham Trevor A. , Sottoriva Andrea
Published: August 2019

Quantification of the effect of spatial tumor sampling on the patterns of mutations detected in next-generation sequencing data is largely lacking. Here we use a spatial stochastic cellular automaton model of tumor growth that accounts for somatic mutations, selection, drift and spatial constrains, to simulate multi-region sequencing data derived from spatial sampling of a neoplasm. We show that the spatial structure of a solid cancer has a major impact on the detection of clonal selection and genetic drift from bulk sequencing data and single-cell sequencing data. Our results indicate that spatial constrains can introduce significant sampling biases when performing multi- region bulk sampling and that such bias becomes a major confounding factor for the measurement of the evolutionary dynamics of human tumors. We present a statistical inference framework that takes into account the spatial effects of a growing tumor and allows inferring the evolutionary dynamics from patient genomic data. Our analysis shows that measuring cancer evolution using next-generation sequencing while accounting for the numerous confounding factors requires a mechanistic model-based approach that captures the sources of noise in the data.

Citation Format: Kate Chkhaidze, Timon Heide, Benjamin Werner, Marc J. Williams, Weini Huang, Giulio Caravagna, Ann-Marie Baker, Trevor A. Graham, Andrea Sottoriva. Spatially constrained tumor growth affects the patterns of clonal selection and neutral drift in cancer genomic data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4232.
Abstract 4235: Phosphorylation of Serine 861 in the ECT2 guanine nucleotide exchange factor activates Rho family GTPases and is a biomarker for several tumor types
Authors: Wang Dunrui , Qian Xiaolan , Eng Sarah , Nellore Shivani , Papageorge Alex G. , Lowy Douglas R.
Published: August 2019

The Rho family of GTPases, which cycle between inactive GDP-bound and active GTP-bound states, have high activity in many cancers. One mechanism for their activation is by guanine nucleotide exchange factors (GEFs), which stimulate the replacement of GDP-bound Rho with GTP-bound Rho. In this study, we report phosphorylation of Epithelial Cell Transforming 2 (ECT2), which is a Rho family-specific GEF, is a biomarker in several tumor types, based on bioinformatic analysis and biological assays. Our analysis of the NCI Clinical Proteomic Tumor Analysis Consortium (CPTAC) database found that Serine 861 (S861) in ECT2 is more highly phosphorylated in several tumor types compared to its phosphorylation in the relevant normal tissue. S861 phosphorylation is 2.1-fold and 2.4-fold higher in colon cancer and ovarian cancer, respectively, and high S861 phosphorylation in breast cancer is correlated with a poorer prognosis. Phosphorylation of S861 is especially high in triple-negative breast cancer, as it is 2.3-fold higher in this type compared with the other types of breast cancer. Increased phosphorylation of S861 is associated increased ECT2 mRNA and protein levels in colon cancer and breast cancer. In experimental studies, siRNA knockdown of endogenous ECT2 in two triple-negative breast cancer lines resulted in lower levels of RhoA-GTP, Rac-GTP, and Cdc42-GTP, and led to reduced cell migration, cell proliferation, and anchorage-independent growth, suggesting that ECT2 is a key regulator of cellular signaling and oncogenic growth in the triple-negative lines. Conversely, ectopic expression of wild-type ECT2 induced increased levels of RhoA-GTP, Rac-GTP, and Cdc42-GTP and promoted migration, proliferation, and anchorage-independent growth. Compared with wild type ECT2, ectopic expression of ECT2 carrying a phospho-defective (S861A) or phospho-mimic (S861D) mutation, respectively, reduced or enhanced ECT2 GEF and biological activities. Our results indicate that phosphorylation of S861 enhances the pro-oncogenic activity of ECT2, which is correlated with the increased phosphorylation of S861 in the three cancer types, the increased expression of ECT2 in two of these cancer types, and the prognostic significance of S861 phosphorylation in breast cancer. * Dunrui Wang and Xiaolan Qian are Equal contributors

Citation Format: Dunrui Wang, Xiaolan Qian, Sarah Eng, Shivani Nellore, Alex G. Papageorge, Douglas R. Lowy. Phosphorylation of Serine 861 in the ECT2 guanine nucleotide exchange factor activates Rho family GTPases and is a biomarker for several tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4235.