Chloroform fraction of Scutellaria barbata D. Don inhibits the growth of colorectal cancer cells by activating miR‑34a.

Scutellaria barbata D. Don (SB) is a well known formula in traditional Chinese medicine, which exhibits potent anticancer effects on various cancers. Many miRNAs play crucial roles in the regulation of cancer, for instance, miR‑34a functions as a tumor suppressor, and is often downregulated during cancer. In this study, we investigated the role of ECSB in suppressing the growth of human colon cancer HCT‑8 cells, and whether this is mediated by regulation of miR‑34a and its downstream target genes, using real-time PCR and western blot analysis. ECSB treatment significantly inhibited the proliferation of HCT‑8 cells and promoted apoptosis in a dose-dependent manner. In addition, ECSB treatment significantly increased the level of miR‑34a expression and decreased the levels of Bcl-2, Notch1/2 and Jagged1 expression. Furthermore, knockdown of miR‑34a expression through transfection of anti-miR‑34a oligonucleotide was significantly reversed by ECSB treatment. Likewise, knockdown of miR‑34a resulted in significant upregulation of Bcl-2, Notch1/2 and Jagged1 expression, which was reversed following ECSB treatment. Therefore, this study reveals that ECSB inhibited cancer cell growth via promoting apoptosis and inhibiting proliferation, through regulation of miR‑34a. These findings further support the use of ECSB as an effective therapeutic agent against colon cancer.