Browsing by Subject "Gastric cancer"
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Item Augmentation of Nab-Paclitaxel Chemotherapy Response by Mechanistically Diverse Antiangiogenic Agents in Preclinical Gastric Cancer Models(American Association for Cancer Research, 2018-11) Awasthi, Niranjan; Schwarz, Margaret A.; Zhang, Changhua; Schwarz, Roderich E.; Surgery, School of MedicineGastric adenocarcinoma (GAC) remains the third most common cause of cancer-related deaths worldwide. Systemic chemotherapy is commonly recommended as a fundamental treatment for metastatic GAC; however, standard treatment has not been established yet. Angiogenesis plays a crucial role in the progression and metastasis of GAC. We evaluated therapeutic benefits of mechanistically diverse antiangiogenic agents in combination with nab-paclitaxel, a next-generation taxane, in preclinical models of GAC. Murine survival studies were performed in peritoneal dissemination models, whereas tumor growth studies were performed in subcutaneous GAC cell-derived or patient-derived xenografts. The mechanistic evaluation involved IHC and Immunoblot analysis in tumor samples. Nab-paclitaxel increased animal survival that was further improved by the addition of antiangiogenic agents ramucirumab (or its murine version DC101), cabozantinib and nintedanib. Nab-paclitaxel combination with nintedanib was most effective in improving animal survival, always greater than 300% over control. In cell-derived subcutaneous xenografts, nab-paclitaxel reduced tumor growth while all three antiangiogenic agents enhanced this effect, with nintedanib demonstrating the greatest inhibition. Furthermore, in GAC patient-derived xenografts the combination of nab-paclitaxel and nintedanib reduced tumor growth over single agents alone. Tumor tissue analysis revealed that ramucirumab and cabozantinib only reduced tumor vasculature, whereas nintedanib in addition significantly reduced tumor cell proliferation and increased apoptosis. Effects of nab-paclitaxel, a promising chemotherapeutic agent for GAC, can be enhanced by new-generation antiangiogenic agents, especially nintedanib. The data suggest that nab-paclitaxel combinations with multitargeted antiangiogenic agents carry promising potential for improving clinical GAC therapy.Item Cancer-associated fibroblasts influence Wnt/PCP signaling in gastric cancer cells by cytoneme-based dissemination of ROR2(National Academy of Science, 2023) Rogers, Sally; Zhang, Chengting; Anagnostidis, Vasilis; Liddle, Corin; Fishel, Melissa L.; Gielen, Fabrice; Scholpp, Steffen; Pediatrics, School of MedicineCancer-associated fibroblasts (CAFs) are a crucial component in the tumor microenvironment influencing cancer progression. Besides shaping the extracellular matrix, these fibroblasts provide signaling factors to facilitate tumor survival and alter tumor behavior. In gastric cancer, one crucial signaling pathway influencing invasion and metastasis is the Wnt/Planar Cell Polarity (PCP) signaling. The crucial PCP ligand in this context is WNT5A, which is produced by the CAFs, and gastric cancer cells react upon this signal by enhanced polarized migration. Why gastric cancer cells respond to this signal is still unclear, as their expression level for the central WNT5A receptor, ROR2, is very low. Here, we show that CAFs display long and branched filopodia that form an extensive, complex network engulfing gastric cancer cells, such as the gastric cancer cell line AGS. CAFs have a significantly higher expression level of ROR2 than normal gastric fibroblasts and AGS cells. By high-resolution imaging, we observe a direct transfer of fluorescently tagged ROR2 from CAF to AGS cells by signaling filopodia, known as cytonemes. Surprisingly, we find that the transferred ROR2 complexes can activate Wnt/JNK signaling in AGS cells. Consistently, blockage of ROR2 function in the CAFs leads to reduced paracrine Wnt/JNK signaling, cell polarization, and migration of the receiving AGS cells. Complementary, enhanced migration via paracrine ROR2 transfer was observed in a zebrafish in vivo model. These findings demonstrate a fresh role for cytoneme-mediated signaling in the tumor microenvironment. Cytonemes convey Wnt receptors from CAFs to gastric cancer cells, allowing them to respond to Wnt/PCP signals.Item Computational Image Analysis Identifies Histopathological Image Features Associated With Somatic Mutations and Patient Survival in Gastric Adenocarcinoma(Frontiers Media, 2021-03-31) Cheng, Jun; Liu, Yuting; Huang, Wei; Hong, Wenhui; Wang, Lingling; Zhan, Xiaohui; Han, Zhi; Ni, Dong; Huang, Kun; Zhang, Jie; Medicine, School of MedicineComputational analysis of histopathological images can identify sub-visual objective image features that may not be visually distinguishable by human eyes, and hence provides better modeling of disease phenotypes. This study aims to investigate whether specific image features are associated with somatic mutations and patient survival in gastric adenocarcinoma (sample size = 310). An automated image analysis pipeline was developed to extract quantitative morphological features from H&E stained whole-slide images. We found that four frequently somatically mutated genes (TP53, ARID1A, OBSCN, and PIK3CA) were significantly associated with tumor morphological changes. A prognostic model built on the image features significantly stratified patients into low-risk and high-risk groups (log-rank test p-value = 2.6e-4). Multivariable Cox regression showed the model predicted risk index was an additional prognostic factor besides tumor grade and stage. Gene ontology enrichment analysis showed that the genes whose expressions mostly correlated with the contributing features in the prognostic model were enriched on biological processes such as cell cycle and muscle contraction. These results demonstrate that histopathological image features can reflect underlying somatic mutations and identify high-risk patients that may benefit from more precise treatment regimens. Both the image features and pipeline are highly interpretable to enable translational applications.Item Enhancing gastric cancer conventional chemotherapy effects by triple angiokinase inhibitor nintedanib in preclinical models(Frontiers Media, 2023-05-10) Awasthi, Niranjan; Schwarz, Margaret A.; Kaurich, Quinn; Zhang, Changhua; Hilberg, Frank; Schwarz, Roderich E.; Surgery, School of MedicineBackground: Gastric adenocarcinoma (GAC) is the fourth leading cause of cancer death worldwide. Systemic chemotherapy is a preferred treatment option for advanced and recurrent GAC, but response rates and survival prolongation remain limited. Tumor angiogenesis plays a critical role in GAC growth, invasion and metastasis. We investigated the antitumor efficacy of nintedanib, a potent triple angiokinase inhibitor for VEGFR-1/2/3, PDGFR-α/β and FGFR-1/2/3, alone or in combination with chemotherapy, in preclinical models of GAC. Methods: Animal survival studies were performed in peritoneal dissemination xenografts in NOD/SCID mice using human GAC cell lines MKN-45 and KATO-III. Tumor growth inhibition studies were performed in subcutaneous xenografts in NOD/SCID mice using human GAC cell lines MKN-45 and SNU-5. The mechanistic evaluation involved Immunohistochemistry analyses in tumor tissues obtained from subcutaneous xenografts. In vitro cell viability assays were performed using a colorimetric WST-1 reagent. Results: In MKN-45 GAC cell-derived peritoneal dissemination xenografts, animal survival was improved by nintedanib (33%), docetaxel (100%) and irinotecan (181%), while oxaliplatin, 5-FU and epirubicin had no effect. The addition of nintedanib to docetaxel (157%) or irinotecan (214%) led to a further extension in animal survival. In KATO-III GAC cell-derived xenografts carrying FGFR2 gene amplification, nintedanib extended survival by 209%. Again, the addition of nintedanib further enhanced the animal survival benefits of docetaxel (273%) and irinotecan (332%). In MKN-45 subcutaneous xenografts, nintedanib, epirubicin, docetaxel and irinotecan reduced tumor growth (range: 68-87%), while 5-FU and oxaliplatin had a smaller effect (40%). Nintedanib addition to all chemotherapeutics demonstrated a further reduction in tumor growth. Subcutaneous tumor analysis revealed that nintedanib attenuated tumor cell proliferation, reduced tumor vasculature and increased tumor cell death. Conclusion: Nintedanib showed notable antitumor efficacy and significantly improved taxane or irinotecan chemotherapy responses. These findings indicate that nintedanib, alone and in combination with a taxane or irinotecan, has the potential for improving clinical GAC therapy.Item Gastric cancer immunosuppressive microenvironment heterogeneity: implications for therapy development(Elsevier, 2024) Yasuda, Tadahito; Wang, Y. Alan; Medicine, School of MedicineAlthough immunotherapy has revolutionized solid tumor treatment, durable responses in gastric cancer (GC) remain limited. The heterogeneous tumor microenvironment (TME) facilitates immune evasion, contributing to resistance to conventional and immune therapies. Recent studies have highlighted how specific TME components in GC acquire immune escape capabilities through cancer-specific factors. Understanding the underlying molecular mechanisms and targeting the immunosuppressive TME will enhance immunotherapy efficacy and patient outcomes. This review summarizes recent advances in GC TME research and explores the role of the immune-suppressive system as a context-specific determinant. We also provide insights into potential treatments beyond checkpoint inhibition.Item GLI1-mediated regulation of side population is responsible for drug resistance in gastric cancer(Impact Journals, 2017-04-18) Yu, Beiqin; Gu, Dongsheng; Zhang, Xiaoli; Li, Jianfang; Liu, Bingya; Xie, Jingwu; Pediatrics, School of MedicineGastric cancer is the third leading cause of cancer-related mortality worldwide. Chemotherapy is frequently used for gastric cancer treatment. Most patients with advanced gastric cancer eventually succumb to the disease despite some patients responded initially to chemotherapy. Thus, identifying molecular mechanisms responsible for cancer relapse following chemotherapy will help design new ways to treat gastric cancer. In this study, we revealed that the residual cancer cells following treatment with chemotherapeutic reagent cisplatin have elevated expression of hedgehog target genes GLI1, GLI2 and PTCH1, suggestive of hedgehog signaling activation. We showed that GLI1 knockdown sensitized gastric cancer cells to CDDP whereas ectopic GLI1 expression decreased the sensitivity. Further analyses indicate elevated GLI1 expression is associated with an increase in tumor sphere formation, side population and cell surface markers for putative cancer stem cells. We have evidence to support that GLI1 is critical for maintenance of putative cancer stem cells through direct regulation of ABCG2. In fact, GLI1 protein was shown to be associated with the promoter fragment of ABCG2 through a Gli-binding consensus site in gastric cancer cells. Disruption of ABCG2 function, through ectopic expression of an ABCG2 dominant negative construct or a specific ABCG2 inhibitor, increased drug sensitivity of cancer cells both in culture and in mice. The relevance of our studies to gastric cancer patient care is reflected by our discovery that high ABCG2 expression was associated with poor survival in the gastric cancer patients who underwent chemotherapy. Taken together, we have identified a molecular mechanism by which gastric cancer cells gain chemotherapy resistance.Item Identifying therapeutic targets in gastric cancer: the current status and future direction(Oxford University Press, 2016-01) Yu, Beiqin; Xie, Jingwu; Department of Pediatrics, IU School of MedicineGastric cancer is the third leading cause of cancer-related death worldwide. Our basic understanding of gastric cancer biology falls behind that of many other cancer types. Current standard treatment options for gastric cancer have not changed for the last 20 years. Thus, there is an urgent need to establish novel strategies to treat this deadly cancer. Successful clinical trials with Gleevec in CML and gastrointestinal stromal tumors have set up an example for targeted therapy of cancer. In this review, we will summarize major progress in classification, therapeutic options of gastric cancer. We will also discuss molecular mechanisms for drug resistance in gastric cancer. In addition, we will attempt to propose potential future directions in gastric cancer biology and drug targets.Item Low Expression of Programmed Death 1 (PD-1), PD-1 Ligand 1 (PD-L1), and Low CD8+ T Lymphocyte Infiltration Identify a Subgroup of Patients With Gastric and Esophageal Adenocarcinoma With Severe Prognosis(Frontiers Media, 2020-04-28) Däste, Silvio; Eppenberger-Castori, Serenella; Mele, Valentina; Schäfer, Hannah M.; Schmid, Lukas; Weixler, Benjamin; Soysal, Savas D.; Droeser, Raoul A.; Spagnoli, Giulio C.; Kettelhack, Christoph; Oertli, Daniel; Terracciano, Luigi; Tornillo, Luigi; von Holzen, Urs; Medicine, School of MedicinePrognosis of gastric and esophageal cancer is poor and treatment improvements are needed. Programmed cell death 1 receptor (PD-1) interaction with its ligand PD-L1 in tumor micro-environment promotes immune tolerance and blocking monoclonal antibodies have entered clinical practice. However, clinical significance of PD-1 and PD-L1 expression in gastric and esophageal adenocarcinomas, particularly in non-Asian patients, is still unclear. Three tissue microarrays including 190 clinically annotated esophageal (n = 31) and gastric (n = 159) adenocarcinomas and 58 paired mucosa specimens, were stained with PD-1, PD-L1, and CD8-specific reagents in indirect immunohistochemistry assays. PD-L1 expression was detectable in 23.2% of cancer specimens. High PD-1 expression was detectable in 37.3% of cases and high CD8+ infiltration in 76%. PD-L1 and high PD1 expression significantly correlated with each other (rs = 0.404, P < 0.0001) and both significantly correlated with CD8+ infiltration (rs = 0.435, P = 0.0003, and rs = 0.444; P = 0.0004, respectively). CD8+ lymphocyte infiltration correlated with improved survival in univariate (P = 0.009), but not multivariate analysis. Most interestingly, multivariate analysis and Kaplan-Meier curves indicate that combined low PD-1/PD-L1 expression and low CD8+ lymphocyte infiltration significantly correlate with poor prognosis. Our data document the clinical significance of a microenvironmental signature including PD-1/PD-L1 expression and CD8+ lymphocyte infiltration in gastric and esophageal adenocarcinomas and contribute to identify a patients' subset requiring more aggressive peri-operative treatments.Item Pembrolizumab alone or in combination with chemotherapy as first-line therapy for patients with advanced gastric or gastroesophageal junction adenocarcinoma: results from the phase II nonrandomized KEYNOTE-059 study(Springer Nature, 2019-07) Bang, Yung-Jue; Kang, Yoon-Koo; Catenacci, Daniel V.; Muro, Kei; Fuchs, Charles S.; Geva, Ravit; Hara, Hiroki; Golan, Talia; Garrido, Marcelo; Jalal, Shadia I.; Borg, Christophe; Doi, Toshihiko; Yoon, Harry H.; Savage, Mary J.; Wang, Jiangdian; Dalal, Rita P.; Shah, Sukrut; Wainberg, Zev A.; Chung, Hyun Cheol; Medicine, School of MedicineBACKGROUND: The multicohort, phase II, nonrandomized KEYNOTE-059 study evaluated pembrolizumab ± chemotherapy in advanced gastric/gastroesophageal junction cancer. Results from cohorts 2 and 3, evaluating first-line therapy, are presented. METHODS: Patients ≥ 18 years old had previously untreated recurrent or metastatic gastric/gastroesophageal junction adenocarcinoma. Cohort 3 (monotherapy) had programmed death receptor 1 combined positive score ≥ 1. Cohort 2 (combination therapy) received pembrolizumab 200 mg on day 1, cisplatin 80 mg/m2 on day 1 (up to 6 cycles), and 5-fluorouracil 800 mg/m2 on days 1-5 of each 3-week cycle (or capecitabine 1000 mg/m2 twice daily in Japan). Primary end points were safety (combination therapy) and objective response rate per Response Evaluation Criteria in Solid Tumors version 1.1 by central review, and safety (monotherapy). RESULTS: In the combination therapy and monotherapy cohorts, 25 and 31 patients were enrolled; median follow-up was 13.8 months (range 1.8-24.1) and 17.5 months (range 1.7-20.7), respectively. In the combination therapy cohort, grade 3/4 treatment-related adverse events occurred in 19 patients (76.0%); none were fatal. In the monotherapy cohort, grade 3-5 treatment-related adverse events occurred in seven patients (22.6%); one death was attributed to a treatment-related adverse event (pneumonitis). The objective response rate was 60.0% [95% confidence interval (CI), 38.7-78.9] (combination therapy) and 25.8% (95% CI 11.9-44.6) (monotherapy). CONCLUSIONS: Pembrolizumab demonstrated antitumor activity and was well tolerated as monotherapy and in combination with chemotherapy in patients with previously untreated advanced gastric/gastroesophageal junction adenocarcinoma.Item The role of GLI2-ABCG2 signaling axis for 5Fu resistance in gastric cancer(Elsevier, 2017-08-20) Yu, Beiqin; Gu, Dongsheng; Zhang, Xiaoli; Liu, Bingya; Xie, Jingwu; Pediatrics, School of MedicineGastric cancer is a leading cause of cancer-related mortality worldwide, and options to treat gastric cancer are limited. Fluorouracil (5Fu)-based chemotherapy is frequently used as a neoadjuvant or an adjuvant agent for gastric cancer therapy. Most patients with advanced gastric cancer eventually succumb to the disease despite the fact that some patients respond initially to chemotherapy. Thus, identifying molecular mechanisms responsible for chemotherapy resistance will help design novel strategies to treat gastric cancer. In this study, we discovered that residual cancer cells following 5Fu treatment have elevated expression of hedgehog (Hg) target genes GLI1 and GLI2, suggestive of Hh signaling activation. Hh signaling, a pathway essential for embryonic development, is an important regulator for putative cancer stem cells/residual cancer cells. We found that high GLI1/GLI2 expression is associated with some features of putative cancer stem cells, such as increased side population. We demonstrated that GLI2 knockdown sensitized gastric cancer cells to 5Fu treatment, decreased ABCG2 expression, and reduced side population. Elevated GLI2 expression is also associated with an increase in tumor sphere size, another marker for putative cancer stem cells. We believe that GLI2 regulates putative cancer stem cells through direct regulation of ABCG2. ABCG2 can rescue the GLI2 shRNA effects in 5Fu response, tumor sphere formation and side population changes, suggesting that ABCG2 is an important mediator for GLI2-associated 5Fu resistance. The relevance of our studies to gastric cancer patient care is reflected by our discovery that high GLI1/GLI2/ABCG2 expression is associated with a high incidence of cancer relapse in two cohorts of gastric cancer patients who underwent chemotherapy (containing 5Fu). Taken together, we have identified a molecular mechanism by which gastric cancer cells gain 5Fu resistance.