The Antineoplastic Effect of Heparin on Colorectal Cancer: A Review of the Literature

Abstract

Heparin and derivatives are commonly used for thrombophylaxis in surgical colorectal cancer (CRC) patients. Recent studies have suggested that, besides its protective effect on the incidence of venous thromboembolism, heparin has an anti-cancer effect. The aim of this review was to explore the literature and report the antineoplastic effect of heparin and derivatives on CRC. MEDLINE and EMBASE databases were searched for relevant articles. Nineteen studies were included (n = 19). Fifteen were lab studies conducted in vivo or in vitro on CRC cell lines and/or mice (n = 15). Four were in vivo clinical studies (n = 4). CRC tumor growth was reduced by 78% in one study, (p < 0.01), while tumorigenesis was suppressed in heparin-treated mice in seven studies. A high dose of low molecular weight heparin for extended duration significantly reduced post-operative VEGF, suggesting that such a regime may inhibit tumor angiogenesis and distant metastasis. A randomized trial demonstrated the antineoplastic effect of nadroparin as the 6 month survival in palliative patients increased. Another study has reported that disease-free survival of CRC patients was not affected by a similar tinzaparin regime. The anti-cancer properties of heparin and derivatives are promising, especially in lab studies. Further clinical trials are needed to investigate the anti-cancer benefit of heparin on CRC.