Resveratrol suppresses growth and VCAN expression in a Cancer-associated fibroblast-breast Cancer hybrid organoid

Cancer-associated fibroblast (CAF) is a major component of the tumor microenvironment (TME) and promotes breast cancer (BC) progression and drug resistance. Two-dimensional cell culture is insufficient to simulate the protective effects of CAFs on tumors, resulting in experimental bias in drug efficacy assays. CAF-organoid co-culture model applied in this study may help solve this problem. Resveratrol (Res) has been found to suppresses BC growth, yet its effects on CAF-protected BC remain unknown.

Surgical resected BC tissues were harvested and established for BC organoids (BCOs, identified with pathological examination) and isolated for CAFs (identified with immunofluorescence) respectively. BCO-CAF co-culture system was established and was measured for the protection effects of CAFs on BCOs. The system was then treated with Res and tested for EdU proliferation assay and calcein-AM/PI viable/non-viable cell labeling. Biogenic analysis was performed and showed that VCAN from CAFs may be important in this process. Versican (VCAN) expression levels in CAFs with or without Res treatment were evaluated by immunohistochemistry, qRT-PCR, and Western blotting.

19 BCO cases were successfully cultured and confirmed with pathological examination. Res showed inhibitory effects on 15 of the 19 BCO cases (78.95 %). Although CAFs facilitated organoid growth of BCOs by 69.75 ± 14.78 %, Res treatment eliminated this effect and caused extensive cell death (84.97 % ±5.06 %) in CAF-coated BCOs, accompanied by a decrease in VCAN and TGF-β expression in CAFs.

The anti-BC value of Res was further proved by showing its promising suppressive effects on BCOs with or without the presence of CAFs.