Tongxie Yaofang Regulates T Lymphocyte Subsets to Improve Immune Microenvironment of Colorectal Cancer Under Chronic Stress / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the effect of Tongxie Yaofang on the immune microenvironment of colorectal cancer in mice under chronic stress and the underlying mechanism. MethodA total of 40 male SPF BABL/C mice were randomized into normal group， stress group， Tongxie Yaofang group （13.65 g·kg-1）， and Tongxie Yaofang-stress group （13.65 g·kg-1）， with 10 in each group. Chronic restraint stress was induced in mice and administration （ig） of Tongxie Yaofang began after 7 days of stress. On the 14th day， forced swim and tail suspension tests were used to examine the behavioral changes of mice after stress and the subcutaneous colorectal tumor was implanted in each group of mice. The effect of this prescription on the body mass and tumor volume of mice was observed. After the last administration， mouse serum and tumor samples were collected. The content of T lymphocytes （CD3+， CD4+， CD8+， and CD4+/CD8+） in tumor was detected by immunohistochemistry and flow cytometry and levels of corticosterone （CORT） in peripheral blood， and interleukin （IL）-2， interferon-γ （IFN-γ）， IL-6， and IL-10 in the serum were determined by enzyme-linked immunosorbent assay （ELISA）. The protein expression of inhibitor of nuclear factor-κB（IκB） kinase α/β （IKKα/β）， nuclear factor-κB （NF-κB）α （IκBα）， NF-κB p65， and phosphorylated （p）-NF-κB p65 was measured by Western blot. ResultCompared with the normal group， the stress group had large tumor volume （P<0.05）， low content of CD3+， CD4+， and CD4+/CD8+ （P<0.05， P<0.01）， high content of CD8+， low content of T helper 1 （Th1）-secreted IFN-γ （P<0.05）， high content of T helper 2 （Th2）-secreted IL-10 （P<0.05） and CORT （P<0.05）， high protein expression of p-NF-κB p65， NF-κB p65， and IKKα/β （P<0.05）， and low protein expression of IκBα （P<0.05）. Compared with the normal group， the Tongxie Yaofang group showed slow tumor growth， high content of CD3+， CD4+， and CD4+/CD8+ （P<0.01）， low content of CD8+ （P<0.05）， high content of Th1-secreted IL-2 and IFN-γ （P<0.05）， low content of Th2-secreted IL-6 and IL-10 （P<0.05）， low content of CORT， low protein expression of p-NF-κB p65， NF-κB p65， and IKKα/β （P<0.05）， and high protein expression of IκBα （P<0.01）. Tongxie Yaofang-stress group demonstrated slower tumor growth， higher content of CD3+， CD4+， and CD4+/CD8+ （P<0.01）， smaller content of CD8+ （P<0.05）， higher content of IL-2 and IFN-γ （P<0.05）， lower content of IL-6， IL-10 （P<0.05）， and CORT （P<0.05）， lower protein expression of p-NF-κB p65， NF-κB p65， and IKKα/β （P<0.05，P<0.01）， and higher protein expression of IκBα （P<0.01） than the stress group. ConclusionTongxie Yaofang can delay the growth of colorectal cancer under chronic stress and alleviate the deterioration of the immune microenvironment， possibly by inhibiting NF-κB signaling pathway， regulating the function of T lymphocyte subsets， and thus suppressing the secretion of pro-inflammatory factors.