Peptidomimetic suppresses proliferation and invasion of gastric cancer cells by fibroblast growth factor 2 signaling cascade blockage

Role of Basic Fibroblast Growth Factor in Cancer: Biological Activity, Targeted Therapies, and Prognostic Value

Cancer is the leading cause of death worldwide; thus, it is necessary to find successful strategies. Several growth factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF, FGF2), and transforming growth factor beta (TGF-β), are involved in the main processes that fuel tumor growth, i.e., cell proliferation, angiogenesis, and metastasis, by activating important signaling pathways, including PLC-γ/PI3/Ca2+ signaling, leading to PKC activation. Here, we focused on bFGF, which, when secreted by tumor cells, mediates several signal transductions and plays an influential role in tumor cells and in the development of chemoresistance. The biological mechanism of bFGF is shown by its interaction with its four receptor subtypes: fibroblast growth factor receptor (FGFR) 1, FGFR2, FGFR3, and FGFR4. The bFGF–FGFR interaction stimulates tumor cell proliferation and invasion, resulting in an upregulation of pro-inflammatory and anti-apoptotic tumor cell proteins. Considering the involvement of the bFGF/FGFR axis in oncogenesis, preclinical and clinical studies have been conducted to develop new therapeutic strategies, alone and/or in combination, aimed at intervening on the bFGF/FGFR axis. Therefore, this review aimed to comprehensively examine the biological mechanisms underlying bFGF in the tumor microenvironment, the different anticancer therapies currently available that target the FGFRs, and the prognostic value of bFGF.

Combining of immunotherapeutic approaches with chemotherapy for treatment of gastric cancer: Achievements and limitations

Evidence reveals that gastric cancer (GC) is the fifth most common malignancy in humans, and about 770,000 people die from this cancer yearly. It has been reported that new cases and deaths from GC are more common in men than women. Therapeutic approaches, such as surgery, chemotherapy, and radiotherapy, have been common for treating GC. Nevertheless, due to the complications and limitations of these methods, researchers use novel approaches, such as immunotherapeutic or target therapies, to evaluate the effectiveness of treatment in patients with metastatic GC. Studies have shown that monotherapy is usually associated with unpromising outcomes, and combination therapy can be a more practical option for treating metastatic GC. Therefore, to clarify different aspects of chemotherapy and immunotherapy in patients with metastatic GC, this review discussed the achievements and challenges of combining immunotherapeutic methods with chemotherapeutic agents.

Peptidomimetics in cancer targeting

The low efficiency of treatment strategies is one of the main obstacles to developing cancer inhibitors. Up to now, various classes of therapeutics have been developed to inhibit cancer progression. Peptides due to their small size and easy production compared to proteins are highly regarded in designing cancer vaccines and oncogenic pathway inhibitors. Although peptides seem to be a suitable therapeutic option, their short lifespan, instability, and low binding affinity for their target have not been widely applicable against malignant tumors. Given the peptides' disadvantages, a new class of agents called peptidomimetic has been introduced. With advances in physical chemistry and biochemistry, as well as increased knowledge about biomolecule structures, it is now possible to chemically modify peptides to develop efficient peptidomimetics. In recent years, numerous studies have been performed to the evaluation of the effectiveness of peptidomimetics in inhibiting metastasis, angiogenesis, and cancerous cell growth. Here, we offer a comprehensive review of designed peptidomimetics to diagnose and treat cancer.

MicroRNA-936 targets FGF2 to inhibit epithelial ovarian cancer aggressiveness by deactivating the PI3K/Akt pathway

Purpose

MicroRNA-936 (miR-936) was previously reported to be dysregulated and involved in the development of non-small cell lung cancer and glioma. However, the functional roles of miR-936 in epithelial ovarian cancer (EOC) remain unclear. In this study, we aimed to evaluate miR-936 expression in EOC and investigate its regulatory role in EOC cell behavior.

Methods

The expression of miR-936 in EOC was measured by RT-qPCR. Cell proliferation, apoptosis, migration, and invasion in vitro, as well as tumor growth in vivo, were determined by CCK-8, flow cytometry, migration and invasion assays, and xenograft models in nude mice, respectively. Bioinformatics analysis, luciferase reporter assays, RT-qPCR, and Western blot analysis were performed to investigate the relationship between miR-936 and fibroblast growth factor 2 (FGF2).

Results

miR-936 expression was significantly downregulated in EOC tissues and cell lines. Low miR-936 expression was found to be correlated with the tumor size, FIGO stage, and lymphatic metastasis in EOC patients. Functional experiments indicated that ectopic miR-936 expression suppressed EOC cell proliferation, migration, and invasion; promoted cell apoptosis; and decreased tumor growth in vivo. In addition, the FGF2 gene was verified to be a direct target of miR-936 in EOC cells. FGF2 expression levels were upregulated in EOC tissues and were inversely correlated with miR-936 expression. Furthermore, effects of FGF2 silencing were similar to those of miR-936 overexpression in EOC cells. Recovered FGF2 expression rescued the miR-936-induced inhibitory effects in EOC cells. Notably, miR-936 was able to deactivate the PI3K/Akt signaling pathway in EOC cells by regulating FGF2 both in vitro and in vivo.

Conclusion

Altogether, our findings provided initial evidence that miR-936 inhibits the aggressiveness of EOC cells in vitro and in vivo, at least partially, by targeting FGF2-mediated suppression of the PI3K/Akt pathway. Therefore, the miR-936/FGF2/PI3K/Akt pathway is a promising therapeutic target for the treatment of EOC patients.