Anti-angiogenic agents in second-line treatment for metastatic colorectal cancer: the optimization of pharmacological costs

Safety and efficacy review of aflibercept for the treatment of metastatic colorectal cancer

INTRODUCTION

Anti-angiogenic drugs are an efficacious class of therapy in the treatment of patients with metastatic colorectal cancer (mCRC). Aflibercept, a vascular endothelial growth factor (VEGF) trap which binds the angiogenic factors VEGF-A, VEGF-B, and placental growth factor (PIGF) is approved in combination with FOLFIRI chemotherapy following progression after an oxaliplatin-containing regimen.

AREAS COVERED

This report provides a review of the practice-changing clinical studies which have established the use of anti-angiogenic therapy as second-line therapy in mCRC including aflibercept with FOLFIRI (5FU, leucovorin, irinotecan). This review also evaluates aflibercept with other chemotherapy regimens as well as efficacy and safety data from real-world studies.

EXPERT OPINION

Aflibercept in combination with FOLFIRI chemotherapy is an established safe and efficacious regimen for the treatment of mCRC as second-line chemotherapy. Although several toxicities have been described, the majority are either low grade or manageable by drug cessation and supportive therapies. For optimal outcomes, patient selection and close observation of toxicities is essential.

Up-to-date role of aflibercept in the treatment of colorectal cancer

Introduction: Colorectal cancer (CRC) is a major public health problem. Despite major progress understanding the biological basis of this tumor added to the incorporation of optimized diagnostic and therapeutic strategies, prognosis after progression on first-line standard treatment remains poor. Several antiangiogenic treatments have demonstrated improvement in overall survival (OS) in the second-line treatment being aflibercept, a fully humanized recombinant protein, one of them. The results of the VELOUR study showed that the addition of aflibercept to second-line FOLFIRI improved OS and progression-free survival.Areas covered: A literature review of published clinical studies was performed in order to discuss the clinical data on aflibercept in mCRC from early drug development to real-world data.Expert opinion: The combination of aflibercept with FOLFIRI provides a statistical improvement in OS and in all the efficacy endpoints analyzed in the VELOUR trial, showing efficacy independently on time to progression, molecular status, prior biological treatment, or age. Further studies are needed to find new biomarkers and molecular characterization in order to better select patients that could benefit from this treatment.

Nitric oxide synthase inhibitors 1400W and L-NIO inhibit angiogenesis pathway of colorectal cancer

BACKGROUND

It has been widely accepted that angiogenesis plays fundamental roles in colorectal cancer development, and therapeutic targeting of this pathway has achieved promising outcome. Recent reports have highlighted the involvement of nitric oxide synthases (NOS) in the development of angiogenesis in cancer; however, the mechanism and therapeutic value of NOS inhibitors in colon cancer are largely unknown.

OBJECTIVE

In this study, we investigated the effects and mechanism of the NOS inhibitors 1400W and L-NIO on the angiogenesis pathway in colorectal cancer cells.

METHODS

Two colorectal cancer cell lines, HT 29 and HCT 116, were used for in vitro study. The expression of iNOS and eNOS in cells was knocked down via shRNA transfection. MTS assays and wound healing assays were performed to assess cell proliferation and migration after shRNA transfection or treatment with 1400W, L-NIO, and 5-fluorouracil. Human angiogenesis PCR arrays and proteome profiler human angiogenesis arrays were used to detect changes in key genes/proteins involved in modulating angiogenesis after 1400W and L-NIO treatment.

RESULTS

Knockdown of iNOS and eNOS significantly inhibited colorectal cancer cell growth. Treatment with NOS inhibitors inhibited colorectal cancer cell growth and migration, and was associated with suppression of the expression of key genes/proteins involved in the angiogenesis pathway. In addition, the combined use of NOS inhibitors with 5-fluorouracil showed enhanced inhibition of cell proliferation and migration.

CONCLUSION

NOS inhibitors could suppress colorectal cancer cell growth and migration, likely via suppressing the angiogenesis pathway.