Antiproliferative Effects of Bacillus coagulans Unique IS2 in Colon Cancer Cells

• Published in: Nutrition and cancer 2017-10, Vol.69 (7), p.1062-1068
• Main Authors: Madempudi, Ratna Sudha, Kalle, Arunasree M.
• Format: Article
• Language: English
• Subjects: Adenosine diphosphate; Anticancer properties; Apoptosis; Bacillus; Bacillus coagulans - physiology; Bax protein; bcl-2-Associated X Protein - metabolism; Cancer; Caspase; Caspase-3; Cell culture; Cell cycle; Cell death; Cell Proliferation; Cervical cancer; Cervix; Chronic myeloid leukemia; Colon; Colon cancer; Colonic Neoplasms - diet therapy; Colonic Neoplasms - pathology; Colorectal cancer; Cytochrome; Cytochrome c; Cytotoxicity; DNA Fragmentation; HeLa Cells; Humans; Image contrast; K562 Cells; Leukemia; Membrane potential; Membrane Potential, Mitochondrial; Mitochondria; Myeloid leukemia; Poly(ADP-ribose); Poly(ADP-ribose) polymerase; Poly(ADP-ribose) Polymerases - metabolism; Probiotics - pharmacology; Proto-Oncogene Proteins c-bcl-2 - metabolism; Ribose; Toxicity; Tumor cell lines
• ISSN: 0163-5581; 1532-7914
• DOI: 10.1080/01635581.2017.1359317

In the present study, the in vitro anticancer (antiproliferative) effects of Bacillus coagulans Unique IS2 were evaluated on human colon cancer (COLO 205), cervical cancer (HeLa), and chronic myeloid leukemia (K562) cell lines with a human embryonic kidney cell line (HEK 293T) as noncancerous control cells. The Cytotoxicity assay (MTT) clearly demonstrated a 22%, 31.7%, and 19.5% decrease in cell proliferation of COLO 205, HeLa, and K562 cells, respectively, when compared to the noncancerous HEK 293T cells. Normal phase-contrast microscopic images clearly suggested that the mechanism of cell death is by apoptosis. To further confirm the induction of apoptosis by Unique IS2, the sub-G0-G1 peak of the cell cycle was quantified using a flow cytometer and the data indicated 40% of the apoptotic cells in Unique IS2-treated COLO cells when compared with their untreated control cells. The Western blot analysis showed an increase in pro-apoptotic protein BAX, decrease in antiapoptotic protein, Bcl2, decrease in mitochondrial membrane potential, increase in cytochrome c release, increase in Caspase 3 activity, and cleavage of poly(ADP-ribose) polymerase. The present study suggests that the heat-killed culture supernatant of B. coagulans can be more effective in inducing apoptosis of colon cancer cells and that can be considered for adjuvant therapy in the treatment of colon carcinoma.