FGFR4 Gly388Arg Polymorphism Affects the Progression of Gastric Cancer by Activating STAT3 Pathway to Induce Epithelial to Mesenchymal Transition

Exosomes Mediate the Production of Oxaliplatin Resistance and Affect Biological Behaviors of Colon Cancer Cell Lines

BACKGROUND

Colon cancer has high mortality rate which making it one of the leading causes of cancer deaths. Oxaliplatin is a common chemotherapeutic drug, but it has disadvantages such as drug resistance.

OBJECTIVE

The purpose of this study is to explore the mechanism of exosomes in the resistance of oxaliplatin and verify whether elemene and STAT3 inhibitors reverse the resistance to oxaliplatin.

METHODS

Related cell line models were constructed and the proliferation, migration, invasion, apoptosis and resistance to oxaliplatin were evaluated for all three cells of HCT116/L, sensitive cell HCT116 and HCT116+HCT116/L-exosomes (HCT116-exo). It was to explore probable signaling pathways and mechanisms by Western blotting.

RESULTS

HCT116-exo drug-resistant chimeric cells showed greater capacity for proliferation, migration and invasion than HCT116 sensitive cells. After the above cells were treated with oxaliplatin, the apoptosis rate of chimeric drug-resistant cells HCT116-exo and its IC50 increased compared with the sensitive cells HCT116. The proliferation, invasion and migration of cells treated with STAT3 inhibitor or β-elemene combined with oxaliplatin reduced compared with those treated with oxaliplatin or β-elemene alone. The STAT3 inhibitor or β-elemene in combination with oxaliplatin increased the rate of apoptosis relative to oxaliplatin or β-elemene alone. Drug-resistant cell exosomes could promote the EMT process, related to the participation of FGFR4, SHMT2 and STAT3 inhibitors.

CONCLUSION

Drug-resistant cell exosomes could induce resistance, and improve the capacity of colon cancer towards proliferate, invade, migrate and promote the EMT process. The β-elemene combined with oxaliplatin could reverse the above results which might be related to the STAT3 pathway and EMT pathway in colon cancer.

Induction, growth, drug resistance, and metastasis: A comprehensive summary of the relationship between STAT3 and gastric cancer

Gastric cancer is a prevalent and highly lethal malignancy that poses substantial challenges to healthcare systems globally. Owing to its often asymptomatic nature in early stages, diagnosis frequently occurs at advanced stages when surgical intervention is no longer a viable option, forcing most patients to rely on nonsurgical treatments such as chemotherapy, targeted therapies, and emerging immunotherapies. Unfortunately, the therapeutic response rates for these treatments are suboptimal, and even among responders, the eventual development of drug resistance remains a significant clinical hurdle. Signal transducer and activator of transcription 3 (STAT3) is a widely expressed cellular protein that plays crucial roles in regulating cellular processes such as growth, metabolism, and immune function. Aberrant activation of the STAT3 pathway has been implicated in the initiation, progression, and therapeutic resistance of several cancers, with gastric cancer being particularly affected. Dysregulated STAT3 signaling not only drives tumorigenesis but also facilitates the development of resistance to chemotherapy and targeted therapies, as well as promotes metastatic dissemination. In this study, we explored the critical role of the STAT3 signaling cascade in the pathogenesis of gastric cancer, its contribution to drug resistance, and its involvement in the metastatic process. Furthermore, we assess recent advances in the development of STAT3 inhibitors and their potential application as therapeutic agents in the treatment of gastric cancer. This work provides a comprehensive overview of the current understanding of STAT3 in gastric cancer and offers a foundation for future research aimed at improving therapeutic outcomes in this challenging disease.

The leukemia inhibitory factor regulates fibroblast growth factor receptor 4 transcription in gastric cancer

PURPOSE

The gastric adenocarcinoma (GC) represents the third cause of cancer-related mortality worldwide, and available therapeutic options remain sub-optimal. The Fibroblast growth factor receptors (FGFRs) are oncogenic transmembrane tyrosine kinase receptors. FGFR inhibitors have been approved for the treatment of various cancers and a STAT3-dependent regulation of FGFR4 has been documented in the H.pylori infected intestinal GC. Therefore, the modulation of FGFR4 might be useful for the treatment of GC.

METHODS

To investigate wich factors could modulate FGFR4 signalling in GC, we employed RNA-seq analysis on GC patients biopsies, human patients derived organoids (PDOs) and cancer cell lines.

RESULTS

We report that FGFR4 expression/function is regulated by the leukemia inhibitory factor (LIF) an IL-6 related oncogenic cytokine, in JAK1/STAT3 dependent manner. The transcriptomic analysis revealed a direct correlation between the expression of LIFR and FGFR4 in the tissue of an exploratory cohort of 31 GC and confirmed these findings by two external validation cohorts of GC. A LIFR inhibitor (LIR-201) abrogates STAT3 phosphorylation induced by LIF as well as recruitment of pSTAT3 to the promoter of FGFR4. Furthermore, inhibition of FGFR4 by roblitinib or siRNA abrogates STAT3 phosphorylation and oncogentic effects of LIF in GC cells, indicating that FGFR4 is a downstream target of LIF/LIFR complex. Treating cells with LIR-201 abrogates oncogenic potential of FGF19, the physiological ligand of FGFR4.

CONCLUSIONS

Together these data unreveal a previously unregnized regulatory mechanism of FGFR4 by LIF/LIFR and demonstrate that LIF and FGF19 converge on the regulation of oncogenic STAT3 in GC cells.

FGF/FGFR-Dependent Molecular Mechanisms Underlying Anti-Cancer Drug Resistance

Simple Summary

Deregulation of the FGF/FGFR axis is associated with many types of cancer and contributes to the development of chemoresistance, limiting the effectiveness of current treatment strategies. There are several mechanisms involved in this phenomenon, including cross-talks with other signaling pathways, avoidance of apoptosis, stimulation of angiogenesis, and initiation of EMT. Here, we provide an overview of current research and approaches focusing on targeting components of the FGFR/FGF signaling module to overcome drug resistance during anti-cancer therapy.

Abstract

Increased expression of both FGF proteins and their receptors observed in many cancers is often associated with the development of chemoresistance, limiting the effectiveness of currently used anti-cancer therapies. Malfunctioning of the FGF/FGFR axis in cancer cells generates a number of molecular mechanisms that may affect the sensitivity of tumors to the applied drugs. Of key importance is the deregulation of cell signaling, which can lead to increased cell proliferation, survival, and motility, and ultimately to malignancy. Signaling pathways activated by FGFRs inhibit apoptosis, reducing the cytotoxic effect of some anti-cancer drugs. FGFRs-dependent signaling may also initiate angiogenesis and EMT, which facilitates metastasis and also correlates with drug resistance. Therefore, treatment strategies based on FGF/FGFR inhibition (using receptor inhibitors, ligand traps, monoclonal antibodies, or microRNAs) appear to be extremely promising. However, this approach may lead to further development of resistance through acquisition of specific mutations, metabolism switching, and molecular cross-talks. This review brings together information on the mechanisms underlying the involvement of the FGF/FGFR axis in the generation of drug resistance in cancer and highlights the need for further research to overcome this serious problem with novel therapeutic strategies.

FGFR4 Gly388Arg Polymorphism Reveals a Poor Prognosis, Especially in Asian Cancer Patients: A Meta-Analysis

The fibroblast growth factor-4 receptor (FGFR4) is a member of receptor tyrosine kinase. The FGFR4 Gly388Arg polymorphism in the transmembrane domain of the receptor has been shown to increase genetic susceptibility to cancers. However, its prognostic impact in cancer patients still remains controversial. Herein, we performed this meta-analysis to evaluate the clinicopathological and prognostic impacts of the FGFR4 Gly388Arg polymorphism in patients with cancer. We carried out a computerized extensive search using PubMed, Medline, and Ovid Medline databases up to July 2021. From 44 studies, 11,574 patients were included in the current meta-analysis. Regardless of the genetic models, there was no significant correlation of the FGFR4 Gly388Arg polymorphism with disease stage 3/4. In the homozygous model (Arg/Arg vs. Gly/Gly), the Arg/Arg genotype tended to show higher rate of lymph node metastasis compared with the Gly/Gly genotype (odds ratio = 1.21, 95% confidence interval (CI): 0.99-1.49, p = 0.06). Compared to patients with the Arg/Gly or Arg/Arg genotype, those with the Gly/Gly genotype had significantly better overall survival (hazard ratios (HR) = 1.19, 95% CI: 1.05-1.35, p = 0.006) and disease-free survival (HR = 1.25, 95% CI: 1.03-1.53, p = 0.02). In conclusion, this meta-analysis showed that the FGFR4 Gly388Arg polymorphism was significantly associated with worse prognosis in cancer patients. Our results suggest that this polymorphism may be a valuable genetic marker to identify patients at higher risk of recurrence or mortality.

Schlafen 11 predicts response to platinum-based chemotherapy in gastric cancers

BACKGROUND

Although unresectable or recurrent gastric cancers (GC) are frequently treated with platinum-based chemotherapy, response to treatment remains unpredictable. Because Schlafen 11 (SLFN11) is recently identified as a critical determinant of platinum sensitivity, we investigated the potential clinical utility of SLFN11 in the treatment of GC.

METHODS

We analysed the correlation between SLFN11 expression and overall survival in 169 GC patients by our established immunohistochemical approach. The impact of SLFN11 expression on the response to platinum and transition of SLFN11 expression upon long-term treatment with platinum were examined using GC cell lines and organoids.

RESULTS

GC patients with high-SLFN11 expression exhibited significantly better survival than those with low-SLFN11 expression, and the significance increased when we selected patients treated with platinum-based chemotherapy. Knockout of SLFN11 and reactivation of SLFN11 in GC cells conferred resistance and sensitivity to platinum, respectively. In GC cells and organoids, long-term treatment with oxaliplatin suppressed SLFN11 expression while imparting drug resistance. The acquired resistance to oxaliplatin was reversed by reactivation of SLFN11 with epigenetic modifying drugs.

CONCLUSIONS

This is the first report revealing definitive clinical implications of SLFN11 in the treatment of GC patients and providing novel strategies for the drug selection based on SLFN11 expression.