bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 417: Role of programmed cell death protein-1 (PD-1)-targeted immunotherapy in hepatocellular carcinoma
Authors: Li Shaohua , Mei Jie , Wang Qiaoxuan , Wei Wei , Lu Lianghe , Zou Jingwen , Zhao Rongce , Guo Zhixing , Ling Yihong , Wen Yuhua , Lin Wenping , Zheng Lie , Chen Minshan , Guo Rongping
Published: July 2021

Background: Anti-programmed cell death protein-1 (PD-1) immunotherapy has shown promising outcomes in patients with advanced hepatocellular carcinoma(HCC). In practice anti-PD-1 drugs were mostly a part of combination therapy, especially in the Asia-Pacific region. We aimed to evaluate the effectiveness and safety of PD-1 inhibitors in combination therapies for HCC patients through real-world data.

Methods: Between January 2018 and December 2019, patients with HCC who received anti-PD-1 immunotherapy were screened for eligibility. The primary efficacy endpoints included tumor response rate, overall survival(OS), and progression-free survival(PFS). Safety was assessed by immune-related adverse events (iAEs). Univariate and multivariate analyses were conducted to identified the risk factors of prognosis.

Result: A total of 322 patients were included in our study. Anti-PD-1 immunotherapy was combined with locoregional interventional approaches (62.1%) and tyrosine kinase inhibitors TKIs (66.5%). The 3-, 6-, 12- and 18-month OS rate were 97.1%, 90.5%, 72.9%, and 57.3%, respectively. The 3-, 6-, 12- and 18-month PFS rate were 82.3%, 66.5%, 42.1%, and 30.3%, respectively. Overally, objective response rate (ORR) was 38.5%, and disease control rate (DCR) was 83.9%. The total rate of grade 3-4 treatment-related AEs was 5.9%, and laboratory-related AEs was 8.7%.

Conclusion: PD-1-targeted immunotherapy as a part of a combination therapy, was a safe and effective treatment for intermediate and advanced HCC.

Citation Format: Shaohua Li, Jie Mei, Qiaoxuan Wang, Wei Wei, Lianghe Lu, Jingwen Zou, Rongce Zhao, Zhixing Guo, Yihong Ling, Yuhua Wen, Wenping Lin, Lie Zheng, Minshan Chen, Rongping Guo. Role of programmed cell death protein-1 (PD-1)-targeted immunotherapy in hepatocellular 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 417.
Abstract 460: Novel breast cancer biomarker in liquid biopsies and its immune regulatory role
Authors: Ibrahim Safaa A. , Riehl Valerie , Beaman Kenneth D.
Published: July 2021

The discovery of a feasible and specific biomarkers is required for early detection of breast cancer. Breast cancer secretes microvesicles (MV) in large quantities to blood circulation to communicate with distant cells such as immune cells to support tumor growth and prepare the metastatic niche. Our recent studies detected a specific peptide from the a2 isoform vacuolar ATPase (a2NTD) as a component of the MV of breast cancer cells and not from MV of normal mammary epithelial cells. a2NTD expression positively correlates with the invasiveness of breast cancer cells, modulates immune cells, and promotes tumor growth, and metastasis. Detection of a2NTD in liquid biopsies and determination of its regulatory role will offer a feasible and specific biomarker for breast cancer. We revealed that a2NTD were highly expressed in exosomes isolated from plasma of breast cancer patients (BC-Ex) in comparison to isolated exosomes from normal donors (N-Ex). BC-Ex induces the gene expression and the secretion of cancer promoting factors from PBMCs such as IL-8, MCP-1, TNF-α and MMP-9 relative to vehicle control or N-Ex. Angiogenesis assay showed that secreted factors from BC-Ex treated PBMCs promote tube formation in HUVEC cell line. In addition, treatment of whole blood from healthy volunteers with MDA MB-231 MV or recombinant a2NTD drives the neutrophil transition from high density neutrophils (HDN) to Low density neutrophils (LDN). Flow cytometrical analysis showed that LDN possess the PMN-MDSCs markers CD11b+ CD15+ CD14- CD33- HLA-DR-. In addition, a2NTD treatment was associated with decreased internal staining of Arg-1 in neutrophils and the release of Arg-1 suggesting that a2NTD reprograms neutrophils to have immunosuppressive phenotype. Together, this data shows that a2NTD can be a potential predictor of the growth and metastasis of breast cancer.

Citation Format: Safaa A. Ibrahim, Valerie Riehl, Kenneth D. Beaman. Novel breast cancer biomarker in liquid biopsies and its immune regulatory role [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 460.
Abstract 462: The development of a highly efficient diagnostic marker combined with PSA of prostate cancer (PCa)
Authors: Lee SeungBaek , Kim JungJin
Published: July 2021

Prostate-Specific Antigen (PSA) is a well-known diagnosis maker for detecting prostate cancer (PCa) using a serum test. However, PSA testing remains controversial because it shows a high false-positive rate and lacks the sensitivity of PCa patients with low PSA levels, although patients have metastasis. Recently, we found an E3 ubiquitin ligase, WSB1, highly expressed in PCa patients with low PSA levels. Overexpressed WSB1 is found in various human cancers, such as pancreatic cancer, lung cancer, breast cancer, and PCa. Especially with PCa, WSB1 is highly expressed in metastatic PCa. Using RNA seq. database from PCa patients (65 primaries and 25 metastasis), we found that WSB1 is highly expressed in 90% (9/10) of patients among ten primary patients with normal PSA levels and 100% (6/6) of patients among six metastasis patients with normal PSA levels. WSB1 expression shows a significant correlation with aggressive PCa progression. Furthermore, WSB1 can secrete into cell culture media like PSA. Therefore, we suggest that WSB1 could be a highly efficient marker combined with PSA for PCa diagnosis as well as being developed as a screening test for the early detection of PCa in the high-risk group.

Citation Format: SeungBaek Lee, JungJin Kim. The development of a highly efficient diagnostic marker combined with PSA of prostate cancer (PCa) [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 462.
Abstract 493: A novel humanized B-hPD-1/hPD-L1/hTIGIT mouse model reveals enhanced efficacy of combined TIGIT and PD-L1 blockade against cancer
Authors: Liu Chonghui , Zhou Xiaofei , Guo Yanan , Lin Eugene , Yu Luke (Zhaoxue) , Shen Yuelei
Published: July 2021

Immune checkpoint blockade targeting PD-1/PD-L1 has enjoyed tremendous success in the clinic against various advanced stage cancers, unleashing potent and durable immune-mediated control of tumors while vastly improving patient survival. However, only a portion of patients truly benefit, while other cancers, such as breast, prostate, pancreatic, and colon cancers, are largely resistant to PD-1/PD-L1 therapy alone. Targeting additional immunosuppressive proteins could boost the efficacy of anti-PD-1/PD-L1 therapy and bring the benefits of immunotherapy to more patients. TIGIT is a recently identified immune checkpoint protein mainly expressed by T and NK cells. CD155 (PVR) is a high-affinity receptor of TIGIT, while CD112 and CD113 bind it with weaker affinity. CD155 and CD112 can engage CD226, an NK activating receptor also expressed on some CD8+ T cells, and trigger killing of tumors. Competitive binding of TIGIT to CD155 and CD112 would prevent signaling through CD226. Therefore, anti-TIGIT blocking antibodies may enhance the function of NK cells and T cells. Preclinical studies have shown that inhibition of TIGIT promotes proliferation and function of T cells. Combined blockade of both TIGIT and PD1/PD-L1 has also shown superior efficacy over monotherapy against tumors in early phase clinical trials. Given the intensive interest in combined TIGIT and PD-1/PD-L1 therapies for cancer, Biocytogen has established a novel human PD-1/PD-L1/TIGIT triple knock-in (TKI) mouse as a vital tool to pre-clinically evaluate the in vivo efficacy of combined human TIGIT and PD1/PD-L1 blocking agents against tumors compared to either alone. Exon 2 of the mouse PD-1 gene, exon 3 of mouse PD-L1, and exon 2 of mouse TIGIT were replaced by their human homologs in B-hPD-1/hPD-L1/hTIGIT mice. Human PD-1, PD-L1, and TIGIT proteins were expressed in homozygous B-hPD-1/hPD-L1/hTIGIT but not wildtype mice. Immune profiles of B-hPD-1/hPD-L1/hTIGIT mice were similar to those in wild-type C57BL/6 mice, and abnormalities were not observed. Importantly, we showed that combining anti-human PD-L1 and anti-human TIGIT antibodies significantly inhibited the growth of MC38-hPD-L1 tumor cells implanted into B-hPD-1/hPD-L1/hTIGIT mice. Thus, our novel hPD-1/hPD-L1/hTIGIT TKI mice will be very useful for investigating the in vivo efficacy of TIGIT antibodies currently in company pipelines both alone and combined with PD1/PD-L1 antibody drugs.

Citation Format: Chonghui Liu, Xiaofei Zhou, Yanan Guo, Eugene Lin, Luke (Zhaoxue) Yu, Yuelei Shen. A novel humanized B-hPD-1/hPD-L1/hTIGIT mouse model reveals enhanced efficacy of combined TIGIT and PD-L1 blockade against 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 493.
Abstract 535: Molecular profiling of brainstem gliomas by liquid biopsy
Authors: Pan Changcun , Li Tian , Jiang Liping , Yan Hai , Zhang Liwei
Published: July 2021

Background: Brainstem gliomas are heterogeneous diseases, many of which are difficult to safely resect and have limited treatment options due to their location. These constraints pose challenges to biopsy, which limits the use of routine molecular profiling and identification of personalized therapies. Here, we explored the potential of sequencing of circulating tumor DNA (ctDNA) isolated from the cerebrospinal fluid (CSF) of brainstem glioma patients as a less invasive approach for tumor molecular profiling.

Cohorts and Methods:A retrospective analysis of brainstem glioma patients with CSF and tumor tissue available was completed. CSF was obtained from patients either intraoperatively (91.2%, 52/57), from ventricular-peritoneal shunt (3.5%, 2/57), or by lumbar puncture (5.3%, 3/57), all prior to surgical manipulation of the tumor. Deep panel sequencing of glioma-associated genes was performed on CSF-derived ctDNA and, where available, matched blood and tumor DNA from 57 patients, including nine medullary and 23 diffuse intrinsic pontine gliomas (DIPG). In addition, we have now completed a prospective study, in which 12 preoperative CSF samples were obtained from lumbar puncture and used to isolate and characterize ctDNA.

Results: In the retrospective analysis, at least one tumor-specific mutation was detected in over 82.5% of CSF ctDNA samples (47/57). In cases with primary tumors harboring at least one mutation, alterations were identified in the CSF ctDNA of 97.3% of cases (36/37). In over 83% (31/37) of cases, all primary tumor alterations were detected in the CSF, and in 91.9% (34/37) of cases, at least half of the alterations were identified. Among ten patients found to have primary tumors negative for mutations, 30% (3/10) had detectable somatic alterations in the CSF. Finally, mutation detection using plasma ctDNA was less sensitive than sequencing the CSF ctDNA (38% vs. 100%, respectively). In the prospective study, at least one tumor-specific mutation was detected in over 83.3% of CSF ctDNA samples (10/12), which is consistent with the data from the retrospective cohort.

Conclusion: Our study indicates that deep sequencing of CSF ctDNA is a reliable technique for detecting tumor-specific alterations in brainstem tumors. This approach may offer an alternative approach to stereotactic biopsy for molecular profiling of brainstem tumors.

Citation Format: Changcun Pan, Tian Li, Liping Jiang, Hai Yan, Liwei Zhang. Molecular profiling of brainstem gliomas by liquid biopsy [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 535.
Abstract 565: A single institutional experience with droplet digital polymerase chain reaction (ddPCR) liquid biopsy for therapeutic decision in avanced solid tumors
Authors: Murad Andre Marcio
Published: July 2021

Droplet digital polymerase chain reaction (ddPCR) is a promising method for analyzing minor amounts of cell-free circulating free nucleic acid (DNA and RNA) due to its high sensitivity, low cost, and fast reading, since it dispenses bioinformatics, making it an appropriate alternative to new generation sequencing (NGS) for the detection of biomarkers to guide molecularly targeted cancer therapy. The assay covers main actionable hotspot alterations across many actionable genes: EGFR(mutations), ALK (fusion, mutations), ROS1(fusion), BRAF(mutations), KRAS (mutations), NRAS(mutations), PIK3CA (mutations), ERBB2(CNV- copy number variation), ESR1(mutations), KIT(CNV) and PDGFRA(CNV). Therefore, our genes can be used in panels, both in therapeutically applied genotyping and in detecting molecular responses as well as in secondary resistance to tumors such as NSCLC, breast, cervix. rectal, GIST, melanoma and pancreas. METHODS: dd-PCR was performed using the QX200 system (BIO-RAD®, Hercules). The extraction of DNA and RNA was done using the magnetic beads technique of Thermofisher's MagMAX Kit. All samples were tested in duplicate. Up to now, 108 metastatic cancer patients were tested: NSCLC - 28 (26%), breast - 22 (20%), colorectal - 22(20%), melanoma - 18(17%), pancreas - 8(7%), ovarian - 6(6%), salivary glands - 2 (4%) and GIST 2(4%). RESULTS: Significant genomic alterations were detected in 38(35%) patients: 10 (9%) mutations in the KRAS G12V gene (all in colorectal cancer), 10 (9%) ERBB2 amplification (breast cancer), 4 (3.65%) EGFR L858R mutations (NSCLC), 4 (3.5%) EGFR del19 mutations (NSLC), 4 (3.5%) EGFR T790M mutations (NSCLC), 4 (3.5%) BRAF-V600E mutations (colon and melanoma), 2 (1.8%) ALK-EML4 fusion (NSCLC). The MAF (Mutant Allele Fraction) ranged from 0.9% to 24%. In all cases, the results were decisive for the indication or change of a targeted therapy. Median turnaround time was 36 hours and the average cost of the panels was around 500 USD (median of 4 genes per panel). CONCLUSION: Our results suggest that dd-PCR is a highly sensitive method and could be used for a routine laboratory detection of the important genomic variations to determine the targeted therapy in patients with varied advanced solid tumors.

Citation Format: Andre Marcio Murad. A single institutional experience with droplet digital polymerase chain reaction (ddPCR) liquid biopsy for therapeutic decision in avanced solid tumors [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 565.
Abstract 570: Detecting cancer using genome-wide cfDNA nucleosomal fragmentation in a prospective multi cancer cohort
Authors: Carey Jacob , Leal Alessandro , Chesnick Bryan , Butler Denise , Rongione Michael , Jones Sian , Scharpf Rob , Villadsen Mette , Bojesen Stig E. , Johansen Julia S. , Feltoft Claus L. , Velculescu Victor E. , Dracopoli Nicholas C.
Published: July 2021

Genome-wide cfDNA fragmentation patterns have previously been demonstrated to distinguish with high sensitivity and specificity between plasma samples from individuals with and without cancer. To further evaluate cfDNA fragmentation as a blood-based screening test for cancer, we have used low coverage whole genome sequencing to analyze plasma samples from 280 patients referred to an advanced diagnostic center due to non-organ specific signs and symptoms of cancer. Within three months of inclusion, 74 of these patients were diagnosed with one of 16 different solid cancers while 206 patients did not have cancer. Using an improved version of our genome-wide cfDNA fragmentation analyses, we observed high performance in distinguishing cancer and non-cancer samples (AUC=0.92, 95% CI 0.88-0.96), including lung cancer (n=12, AUC=0.91, 95% CI 0.80-1.00) and colorectal cancer (n=12, AUC=0.94, 95% CI 0.89-0.99). Although many of the patients in this cohort had other common illnesses including cardiovascular, autoimmune, and inflammatory diseases, the machine learning models of cfDNA fragmentation were able to detect cancer with high sensitivity and specificity. These data support the development of genome-wide cfDNA fragmentation analyses as a non-invasive detection screening approach for both single and multiple cancers.

Citation Format: Jacob Carey, Alessandro Leal, Bryan Chesnick, Denise Butler, Michael Rongione, Sian Jones, Rob Scharpf, Mette Villadsen, Stig E. Bojesen, Julia S. Johansen, Claus L. Feltoft, Victor E. Velculescu, Nicholas C. Dracopoli. Detecting cancer using genome-wide cfDNA nucleosomal fragmentation in a prospective multi cancer cohort [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 570.
Abstract 585: A robust method for expanding patient-derived circulating tumor cells ex vivo
Authors: Xiao Jerry , Kassner Joshua D. , Stanton Kelly , Schlegel Richard , Pohlmann Paula R. , Agarwal Seema
Published: July 2021

In the United States, an estimated 280,000 people will be diagnosed with invasive breast cancer, which has a 5-year survival rate of 27% and 22% in females and males, respectively. Despite the clinical burden of metastasis, the underlying machinery of metastasis remains unclear. This is largely due to a lack of available technologies that can robustly expand patient-derived metastatic cell populations for study ex vivo. One such population is circulating tumor cells (CTCs), which are cells that escape from the primary tumor, intravasate through blood vessel endothelium, and circulate throughout the body. Eventually, CTCs will extravasate at the metastatic site and become the seeds for metastatic colonization. Based on their role in metastasis, CTCs yield great promise for identifying key mechanistic drivers of metastasis. Unfortunately, CTCs exist in low levels within the blood (typically < 100 cells/10mL of blood). Previous methods for culturing CTCs ex vivo have reported low success rates (~ 20%), and often depend on the presence of a high number of CTCs for success. To better interrogate the mechanisms of metastasis, robust methods to propagate CTCs for study are needed. Recently, our lab developed a method using an unbiased selection criterion for isolating and propagating CTCs derived from metastatic breast cancer, yielding 100% success in twelve distinct individuals. This method, based on a density gradient centrifugation, extracts not only CTCs from blood plasma, but also includes potential cancer-associated neutrophils and macrophages. All cultures under our conditions demonstrated growth for > 30 days and were confirmed to have an epithelial and breast phenotype. Notably, 6/12 samples grew longer and were associated with increased CD45 expression using qRT-PCR. We have also recently demonstrated further success in culturing CTCs derived from a variety of other cancers, including colorectal, lung, and pancreatic cancers. This study therefore not only defines a novel technology for expanding CTCs, but also suggests a deficiency in modern isolation methods, which rely on CD45 exclusion, that is limiting culture success in previous methods.

Citation Format: Jerry Xiao, Joshua D. Kassner, Kelly Stanton, Richard Schlegel, Paula R. Pohlmann, Seema Agarwal. A robust method for expanding patient-derived circulating tumor cells ex vivo [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 585.
Abstract 629: Flavonoids are NR4A1 antagonists and target PAX3-FOXO1 and G9a in alveolar rhabdomyosarcoma cells
Authors: Shrestha Rupesh , Mohankumar Kumaravel , Martin Gregory , Safe Stephen
Published: July 2021

Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma that is primarily observed in children and adolescent, and accounts for 50% of soft tissue sarcomas in children. There are two major forms of RMS, namely embryonal RMS (ERMS) and alveolar RMS (ARMS) and these tumors are readily distinguished by their histological and genomic characteristics. ERMS patients have a better prognosis than ARMS patients and both groups undergo radiation, surgical and chemotherapeutic regiments. Many ARMS patients express different oncogenes including the histone methyltransferase G9a and the PAX3-FOXO1 fusion gene that contribute to ARMS cell growth, survival and migration/invasion. Studies in this laboratory have demonstrated that both G9a and PAX3-FOXO1 are regulated by the orphan nuclear receptor 4A1 (NR4A1) and can be targeted by bis-indole derived (CDIMs) NR4A1 antagonists. A recent study showed that the flavonoid kaempferol decreased G9a expression in gastric cancer cells and we hypothesized that kaempferol may be an NR4A1 ligand. Kamepferol and quercetin were used as models and both compounds bound NR4A1 at low μM concentrations and decreased NR4A1-dependent transactivation in ARMS cells. Functional studies showed that like CDIM/NR4A1 ligands, kaempferol and quercetin decrease ARMS cell growth, survival and migration/invasion, consistent with their activity as antagonists and inhibitors of NR4A1 regulated pro-oncogenic functions. In addition, kaempferol and quercetin also decreased expression of G9a, PAX3-FOXO1 and downstream genes regulated by them in ARMS cells further demonstrating their activity as NR4A1 antagonists. These results suggest that NR4A1-active flavonoids could be readily incorporated into chemotherapies used for treatment of ARMS patients to improve their efficacy and decrease the toxic side-effects of currently used cytotoxic drugs.

Citation Format: Rupesh Shrestha, Kumaravel Mohankumar, Gregory Martin, Stephen Safe. Flavonoids are NR4A1 antagonists and target PAX3-FOXO1 and G9a in alveolar rhabdomyosarcoma 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 629.
Abstract 649: Classics to diagnostics: Assessing EMT biomarkers in colorectal cancer prognosis
Authors: Patel Rohin , Robertson Angelique , Saxena Anjana , Patel Mintoo
Published: July 2021

Colorectal cancer (CRC) is a second most common cause of cancer death in the United States and exhibits disparities among racial and ethnic minorities. Colon polyps are abnormal growth in the epithelium that can rapidly invade surrounding mesenchyme and metastasize to form multiple secondary tumor sites. Such Epithelial-Mesenchymal Transition (EMT) is the fundamental event that results in lower survival rate for CRC patients. Altered EMT processes are also indicative of health disparity as observed for aggressive nature of prostate cancer in African Americans. In search of potential diagnostic markers that enable us to capture this transition in situ in CRC, we focused on two major biomarkers, E-Cadherin, an epithelial specific surface protein, and Vimentin, a mesenchymal specific cellular filament component. We obtained de-identified biopsy tissues samples of different stages in CRC, classified as precancerous and cancerous, along with the normal tissues, that were collected during colonoscopies for routine histopathological evaluation. In parallel, these formalin fixed paraffin embedded tissues were immunostained for the expression of E-Cadherin and Vimentin. As expected, normal tissue specimens expressed E-Cadherin exclusively in the mucosal epithelial cells while mesenchymal cells in the stroma specifically stained for vimentin expression. Interestingly, in some precancerous and cancerous specimens, we observed vimentin-positive foci within epithelial cells that lack E-Cadherin expression. This suggests a proof-of principal that an initiation of epithelial to mesenchymal transition can be detected at the clinics by performing selective immunofluorescence staining of these markers. More importantly, such detection can be correlated with the stage of the CRC that can be very insightful for the progression of the disease. Early detection in CRC through these biomarkers to supplement histopathological evaluation is promising and would provide more predictive and detailed analysis of cancer progression in tissue samples to aid in the choice of appropriate treatment plan. The accurate pre-treatment patient evaluation is pivotal to the modern push for personalized therapy. The array of early detection biomarkers will also enhance our understanding in health disparity in CRC when a large set of samples are analyzed for these markers.

Citation Format: Rohin Patel, Angelique Robertson, Anjana Saxena, Mintoo Patel. Classics to diagnostics: Assessing EMT biomarkers in colorectal cancer prognosis [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 649.
Abstract 66: BCG can subvert patients antitumor immune response by downregulating HLA-I expression on cancer cells
Authors: Rouanne Mathieu , Adam Julien , Radulescu Camélia , Mouraud Séverine , Bredel Delphine , Letourneur Diane , Tan Tuan Zea , Signolle Nicolas , Bigorgne Amélie , Dussiot Michael , Susini Sandrine , Tselikas Lambros , Danlos François-Xavier , Chabanon Roman , Schneider Anna K. , Vacher Sophie , Lebret Thierry , Bièche Ivan , Allory Yves , Soria Jean-Charles , Thiery Jean Paul , Zitvogel Laurence , Marabelle Aurélien
Published: July 2021

Patients with high-risk non muscle-invasive bladder cancer (NMIBC) frequently relapse after standard BCG immunotherapy and have a dismal outcome after progression to muscle-invasive bladder cancer (MIBC). The mechanisms of tumor resistance to such immunotherapy remain elusive. We performed functional assays of fresh bladder tumors mixed with BCG, reinforced with in vitro experiments and in situ immune profiling of a cohort of MIBC pre- and post BCG therapy. Here, we demonstrate two distinct patterns of BCG-induced immune subversion. In the first pattern, intracellular BCG infection was associated with HLA-I loss and epithelial-to- mesenchymal transition (EMT) characteristics. HLA-I deficient tumors displayed a myeloid immunosuppressive microenvironment and dismal outcomes. Conversely, HLA-I+ BCG-treated tumors generated a Th1 type of immune response associated with an upregulation of exhaustion markers. Such patients had a very favorable outcome upon radical surgery. We surmise that HLA-I expression in bladder cancers does not result from immunoediting but rather from a BCG-induced EMT process that predicts dismal prognosis. Cancer cells HLA-I scoring by immunohistochemistry (IHC) staining can be easily implemented by pathologists in routine practice in order to stratify future urothelial cancer patient treatment strategies.

Citation Format: Mathieu Rouanne, Julien Adam, Camélia Radulescu, Séverine Mouraud, Delphine Bredel, Diane Letourneur, Tuan Zea Tan, Nicolas Signolle, Amélie Bigorgne, Michael Dussiot, Sandrine Susini, Lambros Tselikas, François-Xavier Danlos, Roman Chabanon, Anna K. Schneider, Sophie Vacher, Thierry Lebret, Ivan Bièche, Yves Allory, Jean-Charles Soria, Jean Paul Thiery, Laurence Zitvogel, Aurélien Marabelle. BCG can subvert patients antitumor immune response by downregulating HLA-I expression on 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 66.
Abstract 7: Modeling cell-cell crosstalk in TNBC brain metastasis
Authors: Zhao Hong , Wang Xin , Liu Nikola , Sheng Jianting , Wong Stephen
Published: July 2021

Brain metastasis (BrM) is a difficult clinical problem in triple-negative breast cancer (TNBC) patients: it occurs in 25% to 40% of metastatic patients while two-year survival rate stubbornly remains a single digit. TNBC usually spreads to the brain rapidly at earlier stages or before the diagnosis of primary cancer. The shorter development time of BrM in TNBC and shorter survival time after BrM diagnosis may indicate a unique innate ability of TNBC tumor cells in adapting to the brain. Indeed, emerging data including ours indicates that TNBC tumor cells have intrinsic brain-like traits resulting in brain-tropism metastasis. Our preliminary studies identified enriched and diverse expressions of receptors and transporters of various neuro-active substances in brain metastatic TNBC cells, including neurotransmitters, gliotransmitters, neurotrophic factors and neural cytokines. By immunopanning astrocytes and microglia/macrophages from mouse brains bearing TNBC brain metastatic tumors at day 3 post tumor cell injection through left cardiac ventricle, and use the CCCExplorer software in modeling the interactions among tumor cells, astrocytes, and microglia/macrophage with cell-type specific RNAseq data, we identified several novel crosstalk signaling, including tumor autocrine TPH1-HTR2, astrocyte→tumor PCDH7-EGFR, IL6-IL6R, CCL5-CCR5 and VGF-C3AR1, and microglia/macrophage→tumor ARTN-GFAR3. Functional experiments demonstrated that cell type-specific depletion of the secreted neuro-active substances deactivated the activities of corresponding receptor and downstream signaling in co-cultured BrM tumor cells. Given that more complex paracrine/autocrine signaling network may dynamically evolve during BrM development, we are characterizing the spatiotemporal cell-cell crosstalk in the BrM metastatic niche that will have important implications for novel therapeutics development.

Citation Format: Hong Zhao, Xin Wang, Nikola Liu, Jianting Sheng, Stephen Wong. Modeling cell-cell crosstalk in TNBC brain metastasis [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 7.
Abstract 70: Obesity-induced impairment of antitumor immunity is associated with an immunosuppressive tumor immune landscape
Authors: Pazdrak Barbara , Mak Duncan , Damsky William , Bosenberg Marcus , Lochmann Brooklyn , Gubin Matthew , McQuade Jennifer
Published: July 2021

Obesity is associated with an increased risk and progression in a variety of cancers. In melanoma, obesity is associated with an increased risk of recurrence following surgical resection which may reflect immune escape of cancer surveillance. We sought to examine the impact of obesity on antitumor immunity in an immunogenic preclinical melanoma model.Male C57/Bl6 mice were fed a 45% fat diet or 10% fat diet for 12 months resulting in obese (body weight 52.8g ±1.3) vs control mice (body weight 38.8g ±2.2). For these studies, we utilized the YUMMER cell line, a C57BL/6J syngeneic melanoma cell line with three driver mutation/deletions (BrafV600E, Pten-/-, Cdkn2a-/-), irradiated to mimic the high mutation burden of human melanoma. 0.5x106 YUMMER cells were subcutaneously injected into the flank of aged (13 month old) control and obese mice. After 14 days post injection, tumors in control mice either had growth arrest or regression. In contrast, all obese mice exhibited progressively growing tumors with 6-fold greater tumor weights after 21 days as compared to control (1.3g ±0.4 vs 0.23g ±0.06). CyTOF analysis of tumor-infiltrating immune cells at day 21 showed 2-fold decrease in the percentage of CD4 T cells in tumors from obese mice (9.8% vs 21.1% of CD45). In addition, obesity resulted in 4-fold increase in the frequency of intratumoral Treg (26.1% vs 8.3% of CD3CD4 cells) and CD8/Treg ratio was 2-fold reduced in obese mice. In contrast to prior findings in obese mice bearing B16 melanomas, the percentage of CD8 T cells expressing PD1 was similar (80.4% vs 74.3%), but we found 2-fold higher frequency of CD8PD1 T cells co-expressing TIM3 and LAG3 in tumors from obese mice (43.3% vs 23.0%). Moreover, obesity also attenuated the frequency of tumor-infiltrating cDC2 (1.4% vs 3.5% of CD45) but did not affect NK cells or B cell proportions. Furthermore, the ratio of tumor infiltrating myeloid cells to T cells was higher in obese mice (1.94:1 vs 0.82:1). Moreover, myeloid cells from obese mouse tumors had higher expression of PDL1, CD206, and CD38 markers.Our findings provide evidence that obesity impairs antitumor immunity by modulating the relative abundance of intratumoral immune cell populations and their phenotypes to promote immunosuppressive microenvironment. These findings will be validated in subsequent studies and examined in human specimens.

Citation Format: Barbara Pazdrak, Duncan Mak, William Damsky, Marcus Bosenberg, Brooklyn Lochmann, Matthew Gubin, Jennifer McQuade. Obesity-induced impairment of antitumor immunity is associated with an immunosuppressive tumor immune landscape [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 70.
Abstract 700: CellSig: A data-driven model of cytokine activity identifies therapeutic targets for severe COVID-19 and cancer immunotherapy-induced colitis
Authors: Jiang Peng , Zhang Yu , Ru Beibei , Ruppin Eytan , Wucherpfennig Kai
Published: July 2021

Studies of cytokine activity are foundational to immunology research. However, the complexity and redundancy of cytokine functions have prevented systematic profiling of signaling activities in biological samples. To address these issues, we developed Cell Signaling Analyzer (CellSig, https://cellsig.ccr.cancer.gov), a data-driven infrastructure to model how cytokines cooperate with and antagonize each other in inflammation processes. We manually curated 20,591 transcriptomic profiles related to human cytokine, chemokine, and growth-factor response. CellSig revealed two main cytokine groups typified by NFKB and interferon-associated signals, respectively. The primary pro-inflammatory members of each group induce a distinct set of secondary signals and are repressed by different anti-inflammatory cytokines. CellSig can reliably predict target activities of 43 cytokines using the transcriptomic data from severe COVID-19 cases, cancer immunotherapy-induced colitis, and immune checkpoint blockade response. Among these clinical applications, the differential activities of the NFKB and interferon cytokine groups revealed potential therapeutic targets for alleviating adverse inflammation without compromising viral clearance or cancer treatment.

Citation Format: Peng Jiang, Yu Zhang, Beibei Ru, Eytan Ruppin, Kai Wucherpfennig. CellSig: A data-driven model of cytokine activity identifies therapeutic targets for severe COVID-19 and cancer immunotherapy-induced colitis [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 700.
Abstract 713: Inhibition of pseudo SARS-CoV-2 binding activity of a anti-cancer polypharmacological agent analogs
Authors: Papineni Rao V. , Adhikary Amitava , Tandon Ritesh , Mitra Dipanwita
Published: July 2021

Severe acute respiratory syndrome coronavirus (SARS-CoV-2), a single-stranded RNA virus with largest genomes (∼ 29,800 bases) of all viruses, causes the infectious disease, COVID-19. SARS-CoV-2 is a zoonotic betacoronavirus transmitted through airborne and fecal-oral routes infecting nasal, lung, and intestinal tissues causing over 26 million confirmed coronavirus disease 2019 (COVID-19) cases and nearly 900,000 associated deaths worldwide as of September 2020. The surface of SARS-CoV-2 is covered with copies of spike glycoprotein (SGP) that plays a pivotal role in virus entry in host cells utilizing angiotensin-converting enzyme 2 (ACE2) as an attachment and entry receptor. We have successfully made a high titer replication-incompetent third-generation lentiviral vector pseudotyped with SARS-2-CoV SGP (pLV-S). Upon successful attachment and entry, the lentiviral vector causes enhanced green fluorescent protein (eGFP) to be expressed in the infected cell. Here, we show how the polypharmacological agent, 2-Deoxy-D-glucose (2-DG), a glucose mimic, and well characterized anti-cancer drug, and its analogs inhibit spike protein binding to the ACE2 receptors. This is as suggested from the 2DG and two analogs inhibition, with a low micromolar affinity, the pLV-S attachment and entry resulting in reduced cell fluorescence of infected HEK293 cells. In addition, we describe 2DG and analogs has the potential to deliver polypharmacological effects on the COVID-through inhibition of glycolysis (at energy status), modulation of inflammatory responses (cytokine storm) and alterations in glycosylation of viral proteins. A unique class of adjuvants and mitigants in the anti-SARS-CoV-2 activity is presented here.

Citation Format: Rao V. Papineni, Amitava Adhikary, Ritesh Tandon, Dipanwita Mitra. Inhibition of pseudo SARS-CoV-2 binding activity of a anti-cancer polypharmacological agent analogs [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 713.
Abstract 739: Preclinical and clinical activity of SAR439859, Amcenestrant, a next generation SERD
Authors: Shomali Maysoun , Sun Fangxian , Besret Laurent , Caron Anne , Lee Joon Sang , El-Ahmed Youssef , Schio Laurent , Pollard Jack , Pelekanou Vasiliki , Cohen Patrick , Celanovic Marina , Herold Christina , Soria Chris , Debussche Laurent , Bouaboula Monsif
Published: July 2021

Primary treatment for estrogen receptor-positive (ER+) breast cancer is endocrine therapy. Selective estrogen receptor degraders (SERDs), such as fulvestrant, induce effective ER signaling inhibition, although clinical studies with fulvestrant report insufficient blockade of ER signaling, possibly due to suboptimal pharmaceutical properties. Here we describe the discovery of SAR439859 (Amcenestrant), a novel, orally bioavailable SERD with potent antagonist and degradation activities against both wild-type and mutant Y537S ER. Driven by its fluoropropyl pyrrolidinyl side chain, SAR439859 has demonstrated broader and superior ER antagonist and degrader activities across a large panel of ER+ cells, compared with other SERDs including improved inhibition of ER signaling and tumor cell growth. Similarly, in vivo treatment with SAR439859 demonstrated significant tumor regression in ER+ breast cancer models including MCF7-ESR1 mutant-Y537S mouse tumors and HCI013, a patient-derived tamoxifen-resistant xenograft tumor. Importantly, in these mutant ESR1 models, we demonstrate that the efficacy of SAR439859 was increased when coadministered with palbociclib, an inhibitor of cyclin-dependent kinase 4 and 6. In the clinical setting, SAR439859 also demonstrated a high level of target engagement, ER degradation and inhibition of ER signaling as well as encouraging anti-tumor activity in heavily pretreated patients with advanced or metastatic ER-positive breast cancer. These findings indicate that SAR439859 would provide therapeutic benefit to patients with ER+ breast cancer, including those who are resistant to endocrine therapy with both wild-type and mutant ER.

Citation Format: Maysoun Shomali, Fangxian Sun, Laurent Besret, Anne Caron, Joon Sang Lee, Youssef El-Ahmed, Laurent Schio, Jack Pollard, Vasiliki Pelekanou, Patrick Cohen, Marina Celanovic, Christina Herold, Chris Soria, Laurent Debussche, Monsif Bouaboula. Preclinical and clinical activity of SAR439859, Amcenestrant, a next generation SERD [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 739.
Abstract 766: Expression of HER-2 statue and PD-L1 is associated with prognosis in gastric cancer
Authors: Lv Huifang , Sun Keran , Nie Caiyun , Chen Beibei , Wang Jianzheng , Xu Weifeng , Wang Saiqi , Liu Yingjun , Zhang Junling , Chen Shiqing , Chen Xiaobing
Published: July 2021

Background PD-L1 and HER-2 as routine biomarkers in gastric cancer (GC). However, little research has been done to investigate the correlation among PD-L1, HER-2, and clinical features in GC.

Methods Between Jan. 2013 and May 2020, a total of 120 GC patients treated with chemotherapy were admitted to Henan Tumor Hospital. We retrospectively identified PD-L1, HER-2 level before chemotherapy and abstracted clinicopathologic features and treatment outcomes. Univariate and multivariate survival analyses were performed to assess the relationship between PD-L1/HER-2 levels and progression-free survival (PFS).

Results We retrospectively analyzed 120 patients with gastric cancer, including 17 patients with HER-2 positive and 103 patients with HER-2 negative GC. The results showed that the expression of PD-L1 was closely correlated with HER-2 gene status, with statistical significance (P =0.015). Patients with PD-L1/HER-2 positive obtained lower PFS compared to PD-L1/HER-2 negative (mPFS: 6.4 vs. 11.1 months, P=0.014, mPFS: 5.3 vs. 11.1 months, P=0.002). And the PD-L1 negative and HER-2 negative had the best PFS than other groups (P=0.0008). In a multivariate model, PD-L1 statue, HER-2 statue, tumor location and tumor differentiation remained independent prognostic indicators for PFS (P<0.05).

Conclusion HER-2 status could predict the efficacy of immune checkpoint inhibitors, and HER-2 status combined with PD-L1 level could predict the prognosis of GC patients.

Citation Format: Huifang Lv, Keran Sun, Caiyun Nie, Beibei Chen, Jianzheng Wang, Weifeng Xu, Saiqi Wang, Yingjun Liu, Junling Zhang, Shiqing Chen, Xiaobing Chen. Expression of HER-2 statue and PD-L1 is associated with prognosis in gastric 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 766.
Abstract 77: MSC loaded oncolytic virus and expressing immunomodulators have therapeutic efficacy in advanced melanomas
Authors: Kanaya Nobuhiko , Vazquez Maria Lopez , Torres Arnaldo J. Franco , Kitamura Yohei , Boland Genevieve M. , Shah Khalid
Published: July 2021

Patients with advanced melanoma have a high propensity to metastasize to the brain and numerous investigational treatments with targeted agents have shown modest response in melanoma brain metastatic patients. Therefore, there is an urgent need to develop innovative therapies for such tumors. Oncolytic herpes simplex virus (oHSV) that selectively replicate in tumor cells and illicit an antitumor effect via oncolysis and production of neoantigens is among the recently approved promising therapies for primary melanoma patients. However, virus neutralization, and inefficient extravasation are the major barriers to the effective systemic delivery of oHSV to target metastatic tumor lesions in the brain. We have previously shown that mesenchymal stem cells (MSC) armed with different oHSV variants (MSC-oHSV) home to metastatic tumor lesions and have therapeutic benefits in melanoma brain metastases (MBM) models. To enhance therapeutic efficacy for metastasis melanoma, we investigated the novel combined therapy using MSC loaded with oHSV and simultaneously MSC releasing GM-CSF. Based on our TCGA data indicating significant loss of PTEN expression in late-stage metastatic melanoma, we tested MSC based therapeutics in PTEN mutant mouse melanomas. We show that MSC loaded oHSV effectively kills PTEN mutant syngeneic tumor cells in vitro. Next, we established MSC secreting GM-CSF and tested the abscopal effects as well as the antitumor efficacy in combination with MSC-oHSV in PTEN mutant syngeneic bilateral subcutaneous tumor model. The combined MSC based therapy showed significant therapeutic effects at both the treated and untreated site compared to control therapies. Interestingly, when these mice after combination therapy were re-challenged with mouse melanoma cells injected into brain, all mice remained tumor free. The combined MSC therapy induced effector memory CD8 and central memory CD8 cells in spleen and there was no toxicity in major organs post-therapy. In conclusion, our data indicate that combined MSC-oHSV/GM-CSF therapy is a promising novel therapy for advanced melanomas.

Citation Format: Nobuhiko Kanaya, Maria Lopez Vazquez, Arnaldo J. Franco Torres, Yohei Kitamura, Genevieve M. Boland, Khalid Shah. MSC loaded oncolytic virus and expressing immunomodulators have therapeutic efficacy in advanced melanomas [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 77.
Abstract 771: Cytokine expression and levels in plasma-derived exosomes are underestimated as contributors to cytokine profiles in cancer patients and healthy donors
Authors: Hong Chang- Sook , Diergaarde Brenda , Whiteside Theresa L.
Published: July 2021

Exosomes play a key role in cell-to-cell signaling. Emerging evidence suggests that biologically active cytokines may be present on the surface or in the lumen of exosomes. We evaluated cytokines in exosomes isolated by size-exclusion chromatography from pre-cleared plasma of 13 patients with head and neck cancer and three healthy donors (HDs). Paired untreated plasma and detergent-treated exosomes were studied by Luminex and cytokine microarrays. On-bead flow cytometry was used to assess relative levels of cytokines on the surface or in the vesicle lumen. Measured by Luminex, for the majority of cytokines (10 of 12), the level observed in plasma was concordant with the level in exosomes. MCP-1 and MIF were the exceptions. They were highly elevated in untreated plasma. Cytokine levels in exosomes determined in parallel by Luminex and the microarray were concordant, except for IL-1β and GM-CSF, which were elevated in Luminex assays. Our data show that only a fraction of most cytokines in untreated plasma is soluble and detectable by Luminex, while the rest is associated with exosomes and can only be detected after exosome permeabilization. Exosome cytokine profiles and levels measured by either method discriminated cancer patients from healthy donors as did levels of soluble cytokines in plasma. By on bead flow cytometry, the relative levels of cytokines in the lumen and on the exosome surface were confirmed for IFN-γ, IL-17, TNF-α and TGF-β, while IL-8 was only detected in the exosome lumen. Thus, cytokines are packaged into exosomes, which carry cytokines on the surface and in the vesicle lumen and contribute to inaccurate, largely underestimated, levels of plasma cytokines reported by laboratories.

Citation Format: Chang- Sook Hong, Brenda Diergaarde, Theresa L. Whiteside. Cytokine expression and levels in plasma-derived exosomes are underestimated as contributors to cytokine profiles in cancer patients and healthy donors [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 771.