Department of Pathology, School of Medicine, University of Phayao, Phayao, Thailand 56000.
School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand 80160.
Exp Oncol. 2023 Oct 11;45(2):220-230. doi: 10.15407/exp-oncology.2023.02.220.
Red rice bran extract (RRBE) contains many biologically active substances exerting antioxidant and anti-inflammatory effects.
To evaluate the anticancer potential of RRBE in human colon cancer cells and its mutagenic/antimutagenic effects on nonmalignant cells.
The cytotoxic effect of RRBE was determined by trypan blue exclusion in HCT116, HT29 cell lines and a non-cancerous HEK293 cell line, and its antiproliferative effect using MTS and colony formation assay. The apoptosis induction was evaluated using ELISA, and the apoptotic rate and cell cycle progression were assessed by flow cytometry. The mutagenic/ antimutagenic potential of RRBE was analyzed by micronucleus assay in the V79 cell line.
RRBE caused a dose-dependent reduction of cell viability in colon cancer cells and showed a limited cytotoxicity against HEK293 cells. The treatment with RRBE suppressed proliferation of HCT116 and HT29 cells and induced apoptosis as evidenced by the increased DNA fragmentation and the apoptotic cell counts. Furthermore, RRBE treatment significantly increased the number of cells at the G2/M phase triggering the arrest of the cell cycle in colon cancer cells. Interestingly, RRBE did not increase the micronucleus frequency in V79 cells but reduced the micronucleus formation caused by mitomycin C.
RRBE effectively suppressed proliferation, induced apoptosis, and caused a cell cycle arrest in human colon cancer cells while being non-mutagenic and exerting antimutagenic effects in vitro.
红米糠提取物（RRBE）含有许多具有抗氧化和抗炎作用的生物活性物质。
评估 RRBE 在人结肠癌细胞中的抗癌潜力及其对非恶性细胞的致突变/抗突变作用。
通过台盼蓝排除法在 HCT116、HT29 细胞系和非癌细胞系 HEK293 中测定 RRBE 的细胞毒性作用，并使用 MTS 和集落形成测定法测定其抗增殖作用。通过 ELISA 评估细胞凋亡诱导，通过流式细胞术评估细胞凋亡率和细胞周期进程。通过 V79 细胞系中的微核试验分析 RRBE 的致突变/抗突变潜力。
RRBE 导致结肠癌细胞的细胞活力呈剂量依赖性降低，对 HEK293 细胞的细胞毒性有限。RRBE 处理抑制了 HCT116 和 HT29 细胞的增殖，并诱导了细胞凋亡，这表现为 DNA 片段化和凋亡细胞计数增加。此外，RRBE 处理显著增加了处于 G2/M 期的细胞数量，从而引发了结肠癌细胞的细胞周期停滞。有趣的是，RRBE 不会增加 V79 细胞中的微核频率，但会减少丝裂霉素 C 引起的微核形成。
RRBE 能有效抑制人结肠癌细胞的增殖、诱导凋亡，并导致细胞周期停滞，同时在体外具有非致突变性和抗突变作用。
