Gastric Cancer Cell Line Model Research Articles

Abstract LB227: Leveraging novel Dato-DXd resistance models to inform biomarker discovery and rational combinations to combat drug resistance

Abstract Datopotamab deruxtecan (Dato-DXd) is an antibody-drug conjugate (ADC) consisting of a humanized anti-TROP2 IgG1 monoclonal antibody covalently linked to a highly potent topoisomerase I (TOP1) inhibitor payload via a stable, tumor-selective, tetrapeptide-based cleavable linker. Despite its promising early clinical signals, drug resistance is a challenge that may emerge with time. The mechanisms of Dato-DXd resistance are currently unknown. Herein, we created and investigated novel models of Dato-DXd resistance to characterize resistance mechanisms and identify novel combinations to overcome Dato-DXd resistance. We used a cyclical dosing method to develop two Dato-DXd acquired resistant NCI-N87 gastric cancer cell line models from in vitro cells (N87-IVR) and in vivo tumors (N87-EVR). The N87-IVR and N87-EVR cells were found to be more than 40-fold resistant to Dato-DXd compared to the parental N87 cells. First, we assessed TROP2 levels, Dato-DXd binding and expression of drug efflux pumps known to have TOP1-inhibitor substrates between the parental and resistant cell populations. Minor changes in each of these were not sufficient to drive Dato-DXd resistance in the drug-tolerant models. Subsequently, we performed a proteogenomic analysis to identify which proteins and pathways were modulated in the resistant phenotype. Both the N87-IVR and N87-EVR cells were divergent from the parental N87 cells and, interestingly, they showed similar yet distinct profiles. Among other changes, our analysis revealed a dramatic loss of SLFN11, a putative DNA/RNA helicase, in both resistant models. Previously published data has shown that a combination with an ATR inhibitor (ATRi) can re-sensitize TOP1 inhibitor-resistant cells in SLFN11-low settings. Consistent with these data, we observed that the ATRi ceralasertib (AZD6738) in combination with Dato-DXd re-sensitizes the resistant NCI-N87 cells in vitro and in vivo. In addition to SLFN11 loss, we also identified a number of other modulations with the potential to drive resistance, e.g. downregulation of the caveolin internalization machinery and interferon response genes. These findings help us refine the mechanism of action of Dato-DXd and shed light on the potential mechanisms of Dato-DXd resistance that may emerge clinically. These data have been used to uncover new biomarkers of Dato-DXd sensitivity and can lead to the development of new clinical strategies to combat Dato-DXd resistance, e.g. the combination with ATRi. Citation Format: Anna Przybyla, Chetan Rane, Gopi Patel, Deepa Bhavsar, Shenghua Wen, David Clark, Yeoun Jin Kim, Alan Lau, Yann Wallez, Jay Mettetal, Wenyan Zhong, Matthew Sung. Leveraging novel Dato-DXd resistance models to inform biomarker discovery and rational combinations to combat drug resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB227.

Novel zinc oxide nanoparticles of Teucrium polium suppress the malignant progression of gastric cancer cells through modulating apoptotic signaling pathways and epithelial to mesenchymal transition

Management of gastric cancer is still challenging due to resistance to current chemotherapeutics and recurrent disease. Moreover, green- synthesized zinc oxide nanoparticles (ZnO-NPs) using natural resources are one of the most promising therapeutic agents for anticancer therapy. Here we report the facile green synthesis and characterization of ZnO-NPs from Teucrium polium (TP-ZnO-NP) herb extract and the anticancer activities of these nanoparticles on gastric cancer cells. Facile green synthesis of TP-ZnO-NP was achieved using zinc acetate dihydrate. For the characterization of TP-ZnO-NP, UV–vis spectroscopy, FTIR, SEM, XRD and EDX analyses were performed. Antiproliferative and anticancer activities of TP-ZnO-NP were explored using the HGC-27 gastric cancer cell line model. MTT cell viability and colony formation assays were used for the analysis of cell proliferation and migration. Wound healing assay was used to analyze the migration capacities of cells. Annexin V/PI double staining, DNA ladder assay, and Acridine orange/Ethidium bromide staining were performed to analyze the induction of apoptosis. qPCR was used to determine gene expression levels of apoptotic and epithelial to mesenchymal transition marker genes. The aqueous extract of TP served as both a reducing and capping agent for the successful biosynthesis of zinc oxide nanoparticles. Remarkably, synthesized TP-ZnO-NPs were found to have significant antiproliferative and anticancer activities on HGC-27 gastric cancer cells. Collectively, current data suggest that TP-ZnO-NP is a novel and promising anticancer agent for future therapeutic interventions in gastric cancer.

Synergistic effects of metformin and curcumin on cytotoxicity of chemotherapy drugs using a gastric cancer cell line model.

Gastric cancer has a weak prognosis and its usual treatments depend on surgery and chemotherapy. These treatments suffer from some drawbacks such as high rates of local recurrence and metastasis, low survival rates, and significantly decreased life quality. Therefore, new therapeutic methods for improved gastric cancer care with minimal side effects seem necessary. Currently, combinatorial treatments for cancer are preferred and recently, metformin (Met) and curcumin (Cur) have been interesting options for this type of therapy. The aim of the present study was to investigate anticancer effects of metformin and curcumin in both single and combinatorial treatment forms on AGS gastric cancer cell line. In comparison to single treatments with each substance, the results of co-treatments with metformin and curcumin indicated synergistic inhibitory effects on cell viability, wound healing, cell migration and invasion, and primary tumor formation. To determine the selective effect of combination of “Met + Cur” on cancerous cells, very low doses of 8 anticancer drugs (cisplatin, carboplatin, oxaliplatin, epirubicin, doxorubicin, docetaxel, paclitaxel, and methotrexate) used in MTT assay were comparatively tested on AGS cancer cells and normal HDF cells for 48 and 72 hours. The results indicated that the combination of “Met + Cur” significantly increased cytotoxic effects of all anticancer drugs of AGS cells. It is while in normal HDF cells, combination of “Met + Cur” along with anticancer drugs had no effect. This can be inferred as selectively additive effect.

Noggin is associated with a poor prognosis of gastric cancer by promoting the proliferation of gastric cancer cells via the upregulation of EGFR.

Noggin is an antagonist of bone morphogenetic proteins(BMP), being indispensable for certain developmental events. The present study aimed to examine the role of Noggin in the development and prognosis of gastric cancer(GC) and to elucidate the underlying mechanisms. The expression of Noggin in GC was evaluated by RT‑qPCR, immunohistochemistry and by the analyses of publicly available databases. The effects of Noggin on proliferation, cell cycle, adhesion, invasion, colony formation and tumour spheroid were examined following both the knockdown and overexpression of Noggin in GC cell lines. The involvement of epidermal growth factor receptor(EGFR) signalling was examined by western blot analysis and by using small molecule inhibitors. As a result, a higher expression of Noggin in GC was found to be associated with a poorer overall survival. Noggin overexpression promoted the proliferation and colony formation of GC cells by promoting cell cycle progression. The knockdown of Noggin in HGC27 cells exerted an opposite effect on proliferation, colony formation and cell cycle progression. Noggin expression positively correlated with EGFR expression in both GC cell line models and The Cancer Genome Atlas human GC cohort. Targeting EGFR and its downstream pathways diminished cell proliferation which was promoted by Noggin. Furthermore, Noggin overexpression resulted in an enhanced nuclear translocation of β‑catenin, leading to an upregulation of EGFR. Thus, the findings of the present study demonstrate that Noggin promotes the proliferation of GC cells by upregulating EGFR and enhancing a vicious circle formed by β‑catenin, EGFR, ERK and Akt.

VEGF-C induced by TGF- \u03b21 signaling in gastric cancer enhances tumor-induced lymphangiogenesis

BackgroundThe role of TGF-β1 in lymph node metastasis and lymphangiogenesis, one of the most important steps of gastric cancer dissemination, is largely unknown. The goal of this study was to investigate the role of TGF-β1 signaling and its molecular mechanisms involved in lymphangiogenesis of gastric cancer.MethodsTwo gastric cell line models, MKN45 and KATOIII, were selected for this study. The protein expression of TGF-β1 pathway molecules and VEGF-C were examined with western blot, or ELISA according to TGF-β1 treatment. To explore whether Smad3 binds to the specific DNA sequences in the VEGFC promoter, we performed an electrophoretic mobility shift assay. Lymphatic tube forming assay and gastric cancer xenograft mouse models were also used to elucidate the effect of TGF-β1 on lymphangiogenesis.ResultsTGF-β1 induced the activation of Smad2/3 and Smad pathway-modulated VEGF-C expression in gastric cancer cell line models. Phosphorylated and activated Smad3 in the nucleus bound to the promoter of VEGFC in KATO III cells. Of note, in MKN45 cells, the Smad-independent AKT pathway was also activated in response to TGF-β1 and induced VEGF-C expression. Inhibition of TGF-β1 signaling down-regulated the expression of VEGF-C. We also confirmed, through tube forming assay and tumor xenograft mouse model, that TGF-β1 increased lymphatic formation, while TGF-β1 inhibition blocked lymphangiogenesis.ConclusionSmad-dependent and -independent TGF-β1 pathways induce VEGF-C, which make lymphangiogenesis around tumor. These findings suggest that TGF-β might be a potential therapeutic target for preventing gastric cancer progression and dissemination.

Small benzothiazole molecule induces apoptosis and prevents metastasis through DNA interaction and c-MYC gene supression in diffuse-type gastric adenocarcinoma cell line

Chemo-resistance has been reported as a relevant barrier for the efficiency of gastric cancer treatment. Therefore, the development of effective and safe drugs for cancer chemotherapy is still a challenge. The purpose of this study was to evaluate the anticancer potential of (E)-2-(((2-(benzo[d]thiazo-2-yl)hydrazono)methyl)-4-nitrophenol) (AFN01) against gastric cancer cell lines. Our results showed promising anticancer activity against gastric cancer cells ACP-02 (IC50 = 1.0 μM) and mild activity against other cell lines including non-malignant gastric cell MNP-01 (IC50 = 3.4 μM). This compound significantly induced S phase cell cycle arrest, prevented cell migration and triggered apoptosis in a concentration-dependent manner. Moreover, AFN01 was significantly more genotoxic against tumoral cell ACP-02, when compared to non-malignant cells, such as MNP-01 and healthy peripheral mononuclear blood cells. AFN01 also synergistically interacts with doxorubicin suppressing cell proliferation and c-MYC gene expression in gastric cancer cell line model, with remarkable c-MYC overexpression. Although further pre-clinical and clinical studies are required to explore its safety and efficiency, AFN01 may represent a promising lead anticancer agent for the treatment of gastric cancer.

Resveratrol inhibits Interleukin-6 induced invasion of human gastric cancer cells

Previous studies show that migration and invasion are the primary causes of death in patients with gastric carcinoma. Increasing evidences have been shown Interleukin-6 could stimulate cancer cells invasion and be associated with cancer development. However, its role in gastric cancer has never been investigated. As an anticancer drug isolated from Chinese medicine, resveratrol was reported to inhibit cancer cells growth and induce apoptosis, but its roles in gastric cancer have not been well understood. In this study, we found that Interleukin-6 was upregulated in blood of gastric cancer patients by enzyme-linked immunosorbent assay. In gastric cancer cell line model, we found that non-cytotoxic concentration of resveratrol inhibited the Interleukin-6 induced SGC7901 cell invasion and matrix metalloproteinases activation. Our studies showed that IL-6 induced SGC7901 cell invasion depends on the Raf/MAPK pathway activation, resveratrol could inhibit this pathway activation. We further showed that resveratrol inhibits the IL-6 induced metastasis by vein injection of luciferase-labeled cancer cells. In conclusion, these results indicate that Interleukin-6 promotes tumor growth and metastasis in gastric cancer, resveratrol has the potential to prevent the Interleukin-6 induced gastric cancer metastasis by blocking the Raf/MAPK signaling activation.

Establishment and characterization of an expanding-type gastric cancer cell line by Ming's classification.

According to Ming's classification, gastric cancer (GC) can be divided into two types: expanding and infiltrative. The two types are readily recognizable by histology: expanding carcinomas grow en masse and by expansion, resulting in the formation of discrete tumour nodules, whereas in infiltrative carcinoma, tumour cells invade individually. Both types show varying degrees of cell maturation. The two types of carcinomas have vastly different pathological and clinical features. However, little is known concerning the mechanisms underlying these differences since no GC cell line models are available. For comprehensive and insightful analyses of mechanisms and treatment methods, new cell lines derived from expanding-and infiltrative-type gastric tumours are urgently needed. In the present study, we established an expanding-type GC cell line from a 72-year-old male patient. Different invitro and invivo methods were used to characterize the phenotypes of this cell line. This GC cell line was named XGC-2 and had an ~60h doubling time. The cell line displayed strong colony formation and tumourigenicity in nude mice and had complicated chromosomal abnormalities. XGC-2 cells showed some markers of epithelial-to-mesenchymal transition (EMT), with decreased E-cadherin expression levels and increased vimentin expression levels. The XGC-2 cell line may be useful for future studies of GC development, progression, metastasis and therapy.

Abstract 3373: TGF-β1 signaling mediated lymphangiogenesis in gastric cancer

Abstract Background Recent evidence showed that Transforming growth factor (TGF)-β1 could have important role for gastric cancer progression and metastasis. However, the role of TGF- β1 for lymph node metastasis and lymphangiogenesis, the important steps of gastric cancer progression, is largely unknown. To investigate the role of TGF-β1 on lymphangiogenesis and its molecular mechanisms is the main purpose of this study. Methods We selected two gastric cancer cell-line models, MKN45 and KATOIII, which hold appropriate characteristics for the current study. We checked the possibility of the autocrine function of TGF-β1 for lymphangiogenesis in these gastric cancer cell-lines. We investigated the changes of TGF-β1 signaling molecules and VEGF-C expression in responding to TGF-β1 and its inhibitor. To examine the binding of Smad3 to the promoter region of VEGF-C, we performed electrophoretic mobility shift assay (EMSA). Both Smad-dependent and Smad-independent pathways were also examined to elucidate which pathways were involved in lymphangiogenesis. Finally, tube forming assay was performed to validate phenotypical effect of TGF-β1 on lymphangiogenesis. Results Two gastric cancer cell-line models, MKN45 and KATOIII, showed autocrine regulation of TGF-β1. TGF-β1 signaling was transduced to VEGF-C, mediated by Smad3. Smad3 was bound to the promoter of VEGF-C which was confirmed with EMSA. Based on EMSA results, KATOIII showed stronger reaction between Smad3 and VEGF-C promoter than MKN45 did. In MKN45, TGF-β1 also transduced its signal to VEGF-C through PI3k-Akt pathway, one of the Smad-independent pathway. Lymphatic endothelial cells cultured in the condition media of MKN45 and KATOIII underwent tubule structure formation. The growth of HLEC was accelerated with TGF-β1 mixed conditioned media, while failed to induce tubular structure in the presence of TGF-β1 inhibitor. The expression level of secreted VEGF-C was as same in responding to TGF-β1 and its inhibitor as the lymphatic tube forming results in gastric cancer cells. Conclusion TGF-β1 could promote lymphangiogenesis through VEGF-C expression in gastric cancer cell line models. TGF-β1 signaling could be transduced through either Smad-mediated or non- Smad-mediated depending on gastric cancer cell-line characteristics. Citation Format: Kyung Ho Pak, Jae-Ho Cheong, Ki Chung Park. TGF-β1 signaling mediated lymphangiogenesis in gastric cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3373.

Establishment and characterization of metastatic gastric cancer cell lines from murine gastric adenocarcinoma lacking Smad4, p53, and E-cadherin.

There is a strong need for murine gastric cancer cell line models recapitulating human gastric cancers. Here, we describe two murine gastric cancer cell lines designated as NCC-S1 and NCC-S3. They were generated from gastric adenocarcinomas that formed in a Villin-cre, Smad4(F/F) , Trp53(F/F) , Cdh1(F/wt) mouse and a Pdx1-cre, Trp53(F/F) , Cdh1(F/F) mouse, respectively. Molecular profiles of both cell lines were very similar to human gastric cancer. NCC-S1M and NCC-S3M subpopulation clones were isolated from pulmonary metastasis of heterotopic allografts of NCC-S1 and NCC-S3 cells, respectively. NCC-S1M and NCC-S3M showed enhanced in vivo growth rates and metastatic potentials and exhibited epithelial-to-mesenchymal transition features. NCC-S1M cells developed orthotopic and heterotopic tumors in immunocompetent mice in predictable manner, and were useful for testing the efficacy of an immunotherapeutic agent, anti-4-1BB antibody. NCC-S1M and NCC-S3M cells demonstrated Wnt/β-catenin pathway activation, and knockdown of Ctnnb1 reversed the metastatic phenotype of NCC-S1M. These results underscore the role of Wnt/β-catenin pathway in metastatic phenotype of gastric cancer. Taken together, our novel metastatic gastric cancer cell lines are useful resources for drug development and metastasis research.

FRZB knockdown upregulates β-catenin activity and enhances cell aggressiveness in gastric cancer

Studies have shown that FRZB correlates with gastric tumorigenicity and may play role in regulating the Wnt/β‑catenin signaling pathway. In the present study, we investigated the correlation between FRZB and the Wnt/β‑catenin signaling pathway using gastric cancer tissues and an FRZB‑knockdown gastric cancer cell line model. The protein levels of FRZB and β‑catenin were examined using immunohistochemical staining. FRZB-specific shRNAs were used to generate FRZB‑knockdown MKN45 gastric cancer cells. Cell proliferation assay, suspending culture and Annexin V/PI double staining analysis were used to investigate the role of FRZB knockdown in cell growth. In vitro migration/invasion assays were performed. The expression of Wnt/β‑catenin downstream targets was analyzed by RT-PCR. FRZB mRNA levels showed negative correlation with β‑catenin levels in paired non-tumor and tumor tissues. FRZB protein levels were negatively correlated with β‑catenin levels analyzed by IHC staining. Furthermore, high FRZB protein levels were correlated with membrane localization of β‑catenin. FRZB knockdown increased gastric cancer cell growth in monolayer and soft agar culture; it increased cell aggregates in suspending culture and rendered less apoptosis which indicated increased anti-anoikis growth. FRZB knockdown increased cell migration and invasion and increased the expression of Wnt/β‑catenin downstream targets such as MMP7 and cyclin D1. Our studies revealed that FRZB levels were correlated with β‑catenin subcellular localization. Knockdown of FRZB in gastric cancer cells increased cell growth and migration/invasion which was also accompanied by activation of Wnt/β‑catenin downstream targets. FRZB knockdown may upregulate the Wnt/β‑catenin pathway and promote aggressiveness in gastric cancer.