New Research: French Grape Seed Oligomeric Proanthocyanidins Suppress Tumor Formation


Mechanistic insights into anticancer properties of oligomeric proanthocyanidins from grape seeds in colorectal cancer.
Ravindranathan P, Pasham D, Balaji U, Cardenas J, Gu J, Toden S, Goel A. Carcinogenesis. 2018 May 28;39(6):767-777.


Although the anticancer properties of oligomeric proanthocyanidins (OPCs) from grape seeds have been well recognized, the molecular mechanisms by which they exert anticancer effects are poorly understood. In this study, through comprehensive RNA-sequencing-based gene expression profiling in multiple colorectal cancer cell lines, we for the first time illuminate the genome-wide effects of OPCs from grape seeds (VX1®) in colorectal cancer.

Our data revealed that OPCs affect several key cancer associated genes. In particular, genes involved in cell cycle and DNA replication were most significantly and consistently altered by OPCs across multiple cell lines. Intriguingly, our in vivo experiments showed that OPCs were significantly more potent at decreasing xenograft tumor growth compared with the unfractionated grape seed extract (GSE) that includes the larger polymers of proanthocyanidins.

These findings were further confirmed in colorectal cancer patient-derived organoids, wherein OPCs more potently inhibited the formation of organoids compared with GSE. Furthermore, we validated alteration of cell cycle and DNA replication-associated genes in cancer cell lines, mice xenografts, as well as patient-derived organoids. Overall, this study provides an unbiased and comprehensive look at the mechanisms by which OPCs exert anticancer properties in colorectal cancer.

What It Means to You:
OPC’s from French Grape Seed Extract show great promise in the fight against cancer. Additionally, this study demonstrates that a specific grape seed OPC extract with small, absorbable compounds outperforms standard grape seed extract that contains large tannins that cannot be absorbed. This is why researchers will be focusing on extracts proven to contain only small, absorbable OPC’s.

Colorectal cancer has the second highest mortality rate in the United States, so finding an effective way to fight it is critical. While lifestyle and diet can prevent or modify the risk, there is an urgent need for effective therapies that don’t come with terrible side effects. Grape seed extract, especially one rich in tannin-free, fully absorbable OPCs can help prevent colon cancers from forming and help stop them from recurring. The French grape seed extract used in the most successful studies outperforms standard grape seed extract, so it is important to choose wisely.