TITLE:
Bioprocessed Black Rice Bran Potentiates the Growth Inhibitory Activity of an Immune Checkpoint Inhibitor against Murine Colon Carcinoma
AUTHORS:
Kyung Hee Lee, Ki Sun Kwon, Woon Sang Hwang, Wha Young Lee, Jeanman Kim, Sang Jong Lee, Sung Phil Kim, Mendel Friedman
KEYWORDS:
Black Rice Bran, Mushroom Mycelia, Bioprocessing, Immune Checkpoint Inhibitor, Mice, Tumor Regression, Cancer Prevention, Biomarkers, Mechanism, Research Needs
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.14 No.12,
December
13,
2023
ABSTRACT: This study determined the effect of orally fed polysaccharide-rich
bioprocessed (fermented) black rice bran produced by culturing with shiitake (Lentinus
edodes) mushroom mycelium on CT-26 colon cancer cells in vivo in an
intracutaneously transplanted mouse tumor alone and in combination with
intraperitoneally administered anti-PD-1 immune checkpoint inhibitor. Analysis
of the isolated tumor weights at the end of the study shows that the average
tumor size in control mice is 3.78 grams, and the average tumor size in mice
treated with anti-PD-1 antibody is 2.16 grams. The average tumor size in mice
treated with BRB-F alone is 2.25 grams, and the average tumor size in mice
treated with anti-PD-1 antibody BRB-F combination is 1.38 grams. Thus, BRB-F or
anti-PD-1 antibody alone each reduce tumor size by 40.5% or 42.9%, whereas the
combination of BRB-F and anti-PD-1 antibody reduces tumor size by 63.5%, with
their cooperative effect being statistically significant. The observed
anti-tumor effects were accompanied by a series of biomarkers associated with
cancer formation and inhibition. These results indicate that the reported
potentiation of cancer therapy using drug-based medical chemotherapies with
added checkpoint inhibitors in human patients are mechanistically similar with
the functional food evaluated in the present study. These beneficial effects in
mice challenge clinicians to investigate if the black rice bran food product
can also protect against human cancer.