Finding a New Prognostic Biomarker for Metastatic Colorectal Cancer

cer progression. However, for these results to be adopted in the clinical filed, it is very important that a large-sample-size study be brought conducted in a validation setting. The findings of this research finding suggest that PlGF may constitute a novel approach to colorectal cancer treatment. Several agents against PlGF have already developed or are currently under development. Among these agents, two novel agents against PlGF will be briefly discussed. Firstly, aflibercept (ZALTRAP) is a recombinant fusion protein that acts as a soluble receptor that binds to VEGF-A, VEGF-B and PIGF. In April 2011, Van Cutsem et al. [3] reported that aflibercept improved the primary endpoint of overall survival in the Velour phase III clinical trial for second-line treatment for metastatic colorectal cancer. Secondly, the humanized anti-PlGF mAb (TB-403) is directed against PlGF. A trial with TB-403 has only completed its first phase. Antitumor activity has been demonstrated with TB-403 in human tumor xenograft models of renal cell carcinomas and hepatocellular carcinomas. The mechanism of action for TB-403 is currently under investigation; preclinical studies suggest its effects may include blocking tumor angiogenesis and primary tumor growth, as well as inhibition of metastasis. In addition, PIGF inhibition may complement and potentiate the antitumor effects of VEGF inhibition, in part by inhibiting macrophage recruitment [4].