A 2017 meta-analysis reported that NSAIDs are associated with lower risk of distant metastasis in patients with breast, prostate, lung, and colorectal cancer.¹

The mechanism accounting for this observation is not fully understood. However, since inflammation has been implicated as a driving force for tumor metastasis ², blunting the inflammatory microenvironment that surrounds tumors may explain NSAIDs’ reported beneficial effect.

NSAIDs may also have a direct effect on cancer cells. In-vitro studies demonstrate that NSAIDs induce the expression of a protein (p75 neurotrophic receptor, p75NTR) associated with suppression of tumor growth and metastasis in prostate cancer; this protein also suppresses growth of bladder cancer cells.^3,4

Ibuprofen and indomethacin are among the commonly available NSAIDS shown to exhibit such anti-tumor effect. Interestingly, non-COX-inhibiting NSAIDS (eg, [R] flurbiprofen, an enantiomer of ibuprofen) may also be effective suggesting that inhibition of cell survival may not be COX-mediated.

Although these findings and observations are promising, randomized-controlled trials are clearly needed to better define the role of NSAIDs in the clinical management of cancer.

 

References: 

1. Zhao X, Xu Z, Li H. NSAIDs use and reduced metastasis in cancer patients: Results from a meta-analysis. Sci Rep 2017; 7:1875. https://www.ncbi.nlm.nih.gov/pubmed/28500305
2. Qian BZ. Inflammation fires up cancer metastasis. Semin Cancer Biol 2017; 47:170-176. https://www.ncbi.nlm.nih.gov/pubmed/28838845
3. Khwaja F, Allen J, Lynch J, Andrews P, Djakiew D. Ibuprofen inhibits survival of bladder cancer cells by induced expression of the p75NTR tumor suppressor protein. Cancer Res 2004; 64:6207-6213. https://www.ncbi.nlm.nih.gov/pubmed/15342406
4. Krygier S, Djakiew D. Neurotrophin receptor p75NTR suppresses growth and nerve growth factor-mediated metastasis of human prostate cancer cells. Int J Cancer 2002; 98:1-7. https://www.ncbi.nlm.nih.gov/pubmed/11857376

Contributed by Camilo Campo, Medical Student, Harvard Medical School, Boston, MA.