A novel angiogenesis inhibitor, Ki23057, is useful for preventing the progression of colon cancer and the spreading of cancer cells to the liver

2,3-Difunctionalized Benzo[b]thiophene Scaffolds Possessing Potent Antiangiogenic Properties

A new class of 2-anilino-3-cyanobenzo[b]thiophenes (2,3-ACBTs) was studied for its antiangiogenic activity for the first time. One of the 2,3-ACBTs inhibited tubulogenesis in a dose-dependent manner without any toxicity. The 2,3-ACBTs significantly reduced neovascularization in both ex vivo and in vivo angiogenic assays without affecting the proliferation of endothelial cells. Neovascularization was limited through reduced phosphorylation of Akt/Src and depolymerization of f-actin and β-tubulin filaments, resulting in reduced migration of cells. In addition, the 2,3-ACBT compound disrupted the preformed angiogenic tubules, and docking/competitive binding studies showed that it binds to VEGFR2. Compound 2,3-ACBT had good stability and intramuscular profile, translating in suppressing the tumor angiogenesis induced in a xenograft model. Overall, the present study suggests that 2,3-ACBT arrests angiogenesis by regulating the Akt/Src signaling pathway and deranging cytoskeletal filaments of endothelial cells.

Fibroblast growth factor receptor 2 overexpression is predictive of poor prognosis in rectal cancer patients receiving neoadjuvant chemoradiotherapy

AIMS

Neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery is an increasingly used therapeutic strategy for advanced rectal cancer, but risk stratification and final outcomes remain suboptimal. Recently, the oncogenic role of the fibroblast growth factor/fibroblast growth factor receptor (FGFR) signalling pathway has been recognised; however, its clinical significance in rectal cancer has not been elucidated. In this study, we identify and validate targetable drivers associated with the FGFR signalling pathway in rectal cancer patients treated with CCRT.

METHODS

Using a published transcriptome of rectal cancers, we found FGFR2 gene significantly predicted response to CCRT. The expression levels of FGFR2, using immunohistochemistry assays, were further evaluated in 172 rectal cancer specimens that had not received any treatment. Expression levels of FGFR2 were statistically correlated with major clinicopathological features and clinical survival in this valid cohort.

RESULTS

High expression of FGFR2 was significantly related to advanced pretreatment tumour (p=0.022) and nodal status (p=0.026), post-treatment tumour (p<0.001) and nodal status (p=0.004), and inferior tumour regression grade (p<0.001). In survival analyses, high expression of FGFR2 was significantly associated with shorter local recurrence-free survival (p=0.0001), metastasis-free survival (MeFS; p=0.0003) and disease-specific survival (DSS; p<0.0001). Notably, high expression of FGFR2 was independently predictive of worse outcomes for MeFS (p=0.002, HR=5.387) and DSS (p=0.004, HR=4.997).

CONCLUSIONS

High expression of FGFR2 is correlated with advanced tumour stage, poor therapeutic response and worse survival in rectal cancer patients receiving neoadjuvant CCRT. These findings indicate that FGFR2 is a prognostic factor for treating rectal cancer.

Inhibition of both focal adhesion kinase and fibroblast growth factor receptor 2 pathways induces anti-tumor and anti-angiogenic activities

FAK and FGFR2 signaling pathways play important roles in cancer development, progression and tumor angiogenesis. PHM16 is a novel ATP competitive inhibitor of FAK and FGFR2. To evaluate the therapeutic efficacy of this agent, we examined its anti-angiogenic effect in HUVEC and its anti-tumor effect in different cancer cell lines. We showed PHM16 inhibited endothelial cell viability, adherence and tube formation along with the added ability to induce endothelial cell apoptosis. This compound significantly delayed tumor cell growth. Together, these data showed that inhibition of both FAK and FGFR2 signaling pathways can enhance anti-tumor and anti-angiogenic activities.

Vascular endothelial growth factor (VEGF) receptors: drugs and new inhibitors

The recent launch onto the market of five VEGFR inhibitors indicates the therapeutic value of these agents and the importance of the research in the field of angiogenesis inhibitors for future oncologic therapy. In this Perspective we briefly report the inhibitors that are in clinical use, while we dedicate two wider sections to the compounds that are in clinical trials and to the new derivatives appearing in the literature. We especially consider the medicinal chemistry aspect of the topic and report the structure-activity relationship studies and the binding mode of some inhibitors as well as the biological data of the compounds discovered in the past 5 years.

Fibroblast growth factor receptor 2: expression, roles, and potential as a novel molecular target for colorectal cancer

The fibroblast growth factor receptor (FGFR) family consists of four members, named FGFR1, 2, 3, and 4. All 4 FGFRs and their ligands, fibroblast growth factors (FGFs), are expressed in colorectal cancer (CRC). Recent studies have shown that FGFR2 plays important roles in cancer progression; therefore, it is of great interest as a novel target for cancers. Expression of FGFR2 regulates migration, invasion, and growth in CRC. Expression of the FGFR2 isoform FGFR2 IIIb was associated with well-differentiated histological types, and its specific ligand, FGF7, enhanced angiogenesis and adhesion to type-IV collagen via FGFR2 IIIb in CRC. FGFR2 IIIc is detected in CRC, but its roles have not been well elucidated. Interactions between FGFR2 IIIb and IIIc and FGFs may play important roles in CRC via autocrine and/or paracrine signaling. Several kinds of molecular-targeting agents against FGFR2 have been developed; however, it is not clear how a cancer treatment can most effectively inhibit FGFR2 IIIb or FGFR2 IIIc, or both isoforms. The aim of this paper is to summarize the roles of FGFR2 and its isoforms in CRC and clarify whether they are potent therapeutic targets for CRC.

Potential dual role of KGF/KGFR as a target option in novel therapeutic strategies for the treatment of cancers and mucosal damages

INTRODUCTION

Keratinocyte growth factor (KGF) and its receptor KGFR play a pivotal role in regulating cell proliferation, migration, differentiation and survival, in response to injury and tissue repair. Altered expression of this pathway in cancer opened the way to the development of targeted therapy to achieve KGFR inhibition. Nevertheless, KGF administration has been demonstrated to ameliorate oral mucositis resulting from chemoradiotherapy, besides protecting epithelial cells against radiation-induced damage.

AREAS COVERED

This review focuses on the potential therapeutic interest of KGF/KGFR in two different areas: selective inhibition of KGFR signaling for the treatment of cancers characterized by upregulation of this pathway and administration of KGF to protect epithelial cells from induced damage. The review presents an overview of therapeutic strategies in both directions.

EXPERT OPINION

KGF/KGFR signaling can contribute to enhancing the malignant potential of epithelial cells and to promoting tumorigenesis. On the other hand, the therapeutic use of KGF in cancer patients provides epithelial protection, reducing chemotherapy side effects. FGFRs have become attractive antitumor targets and various inhibitors have been used to contrast tumor cell growth. The identification of KGFR-specific molecules might represent a promising therapeutic strategy that could increase the window of available agents and treatment methods.

A FGFR2 inhibitor, Ki23057, enhances the chemosensitivity of drug-resistant gastric cancer cells

AIM

The aim of this study was to clarify the ability of a FGFR2 inhibitor, Ki23057, to enhance the chemosensitivity of drug-resistant gastric cancer cell lines when used in combination with chemotherapeutic drugs.

MATERIALS AND METHODS

Five cancer cell lines resistant to irinotecan (SN38), paclitaxel (PTX), etoposide (VP16), oxaliplatin (OXA), and gemcitabine (GEM) were respectively established from a parent gastric cancer cell line, OCUM-2M, and were named OCUM-2M/SN38, OCUM-2M/PTX, OCUM-2M/VP16, OCUM-2M/OXA, and OCUM-2M/GEM. The effects of the combination of Ki23057 with anticancer drugs on proliferation, apoptosis, and mRNA expression were examined.

RESULTS

Ki23057 significantly decreased the IC(50) values of OCUM-2M/SN38, OCUM-2M/PTX, and OCUM-2M/VP16, but not those of OCUM-2M/OXA and OCUM-2M/GEM. Ki23057 significantly enhanced the apoptosis rates induced by chemotherapeutic drugs in both the drug-resistant cell lines and the parental cell line. Ki23057 decreased the ERCC1 expression level in OCUM-2M/SN38, OCUM-2M/PTX, and OCUM-2M/VP16. Ki23057 increased the p53 expression level in OCUM-2M/SN38 and OCUM-2M/PTX, but not in OCUM-2M/VP16.

CONCLUSION

The FGFR2 inhibitor Ki23057 might be therapeutically promising for treating drug-resistant gastric cancer cells, especially when used in combination with SN38, PTX, or VP16. The apoptosis process might be the main mechanism underlying the synergistic effect of these combinations. The ERCC1 and p53 genes may play an integral role in the synergism between Ki23057 and chemotherapeutic agents in drug-resistant cell lines.