Antiproliferative Activities Through Accelerating Autophagic Flux by Basidalin and its Analogs in Human Cancer Cells

Abstract

Basidalin, isolated from the basidiomycete Leucoagaricus naucina, has previously demonstrated antibacterial and antitumor properties against murine cancer cells in vivo, but its effects on human cancer cells remain unknown. In this study, we found that basidalin possesses antiproliferative activity against human cancer cell lines. To elucidate the antiproliferative mechanism of basidalin, we focused on autophagy. Treatment with basidalin led to an increase in LC3-II expression level, and accelerated autophagic flux through an mTOR-independent pathway. Moreover, according to the structure-activity relationship analysis—including newly synthesized basidalin analogs—the formyl group, not the amino group, contributes to the antiproliferative activities of basidalin against human cancer cells. Additionally, the antiproliferative activity of basidalin analogs was strongly correlated with autophagy-inducing activity, indicating that basidalin exhibits antiproliferative activity through autophagy induction. These data suggest that basidalin, characterized by its ability to upregulate autophagic flux, emerges as a novel anticancer drug.

Note:
Funding declaration: This work was supported by the Molecular Profiling Committee and a Grant-in-Aid for Transformative Research Areas (Platforms for Advanced Technologies and Research Resources) from the Ministry of Education, Culture, Sports, Science and Technology, Japan (JSPS KAKENHI Grant Number JP 22H04922).

Conflict of Interests: None.

Keywords: Antibiotic, basidalin, Antiproliferative activity, autophagy inducer, mTOR signal, Structure-activity relationship.