• Postbiotics derived from Enterococcus faecium KCH-1 exhibited significant cytotoxic effects against HT-29 colorectal cancer cells. • The prepared postbiotics induced apoptosis through upregulation of BAX and downregulation of BCL2 genes. • Flow cytometry confirmed cell cycle arrest, increased early/late apoptosis, and elevated ROS generation in treated cells. • Postbiotics markedly suppressed metastatic markers including lncRNA H19, IGF2BP1, and TGF2, while increasing CDH1 expression. • These findings support E. faecium–derived postbiotics as promising, safe bioactive candidates for colorectal cancer therapy. Cancer has a high rate of incidence and mortality worldwide. Among malignancies, colorectal cancer is mentioned as the second leading cause of death. Therefore, novel safe approaches should be developed and applied against colorectal cancer. To achieve this, postbiotics were prepared from the E. faecium strain KCH-1 and applied against HT-29 human colorectal cancer cell lines. After cultivating E. faecium strain KCH-1 (MRS agar and MRS broth), probiotics were prepared. Thereafter, various biomedical analyses, including MTT test, scratch assay, RT-PCR test, cell cycle arrest analysis, apoptosis analysis, and ROS assay, were carried out to investigate the potential ability of the prepared postbiotics in the suppression of HT-29 cells. The MTT assay indicated that prepared postbiotics resulted in 50% cytotoxicity after 48 h incubation at 1000 μg/mL and the IC 50 was attained at 1000 μg/mL (48 h incubation). RT-PCR technique demonstrated the enhanced expression levels of BAX apoptotic gene (nearly 2-fold), reduction of BCL2 antiapoptotic gene (above 2-fold), and induction of mTORC1 autophagy pathway in HT-29 cells after 24 h of incubation with IC 50 . The relative expression levels of metastatic genes were exponentially reduced as well (lncRNA H19: 3-fold; IGF2BP1: 2-fold; and IGF2: 4-fold) whereas the CDH1 gene did increase. Flowcytometry indicated the cell cycle arrest (4.19%), apoptosis-inducing (23.0%), and ROS-inducing (1.3-fold) capability for the prepared postbiotics in HT-29 cells. These data have approved the potential performance of E. faecium strain KCH-1 postbiotics against colorectal cancer cells.
Shafiei et al. (Sun,) studied this question.