A novel compound, ferulic acid-bound resveratrol, induces the tumor suppressor gene p15 and inhibits the three-dimensional proliferation of colorectal cancer cells.

Resveratrol, a phytoalexin present in grapes and other edible foods, has been reported to have beneficial effects against various diseases including cancer. We previously reported that resveratrol and its derivative, caffeic acid-adducted resveratrol, selectively inhibit the three-dimensional (3D) proliferation of a human colorectal cancer cell line, HCT116 with activating KRAS mutation. Herein, we demonstrated that a novel compound, ferulic acid-bound resveratrol, also represses the 3D proliferation of HCT116 cells. We observed that resveratrol conjugated to two ferulic acids represses the 3D proliferation of HCT116 cells more strongly than resveratrol and resveratrol conjugated to one ferulic acid. Resveratrol conjugated to two ferulic acids also inhibited the 3D proliferation of MCF7 human breast cancer cells. We further uncovered that the resveratrol derivative increases the mRNA level of the tumor suppressor p15, a CDK inhibitor that functions as a brake of cell proliferation in HCT116 cells. These results imply that the resveratrol derivative represses 3D proliferation via increasing p15 expression in HCT116 cells.

A novel resveratrol derivative selectively inhibits the proliferation of colorectal cancer cells with KRAS mutation.

Resveratrol is a polyphenolic compound in many edible foods including grapes, peanuts, and berries. Several studies have revealed the beneficial effects of resveratrol against various diseases such as heart disease, diabetes, obesity, neurological disorders, and cancer. A recent study showed that resveratrol inhibits the proliferation of HCT116 human colorectal cancer cells in three-dimensional culture (3DC) via induction of luminal apoptosis in HCT116 cell spheroids. In this study, we showed that a novel compound, caffeic acid-adducted resveratrol, has a stronger inhibitory effect on the growth of HCT116 cell spheroids in 3DC than resveratrol. It showed almost the same inhibitory efficacy as 5-fluorouracil, a conventional anticancer drug. We further showed that the resveratrol derivative did not affect the growth of HKe3 cell spheroids derived from HCT116 cells by disruption of the activating mutant KRAS gene. These results suggest that the resveratrol derivative inhibits the growth of HCT116 cell spheroids via inhibition of an oncogenic KRAS-mediated signaling pathway.

The Long Noncoding RNA OIP5-AS1 Is Involved in the Regulation of Cell Proliferation.

BACKGROUND/AIM: OPA-interacting protein 5 antisense transcript 1 (OIP5-AS1) is a long noncoding RNA located on human chromosome 15q15.1 and transcribed in the opposite direction to OIP5. Here, we report that OIP5-AS1 is involved in regulating cell proliferation. MATERIALS AND METHODS: HeLa cells were transfected with OIP5-AS1-targeting siRNA oligonucleotides and anti-sense oligonucleotides. The cells were harvested 72 h after transfection and subjected to quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and cell-cycle and apoptosis analysis. RESULTS: OIP5-AS1 was expressed at a lower level in cells harbouring an oncogenic kirsten rat sarcoma viral oncogene homolog (K-RAS) mutation than in cells expressing wild-type K-RAS. Silencing OIP5-AS1 with siRNA oligonucleotides or anti-sense oligonucleotides reduced HeLa cell proliferation. Apoptosis and cell-cycle analysis showed that silencing OIP5-AS1 did not cause apoptosis, but did cause G2/M phase cell-cycle arrest. CONCLUSION: These results suggest that OIP5-AS1 positively regulates cell proliferation by promoting G2/M phase progression.