Study Of The Efeect Of Interleukin-22 On The Regulation Of Aerobic Glycolysis In Colon Cancer Cells

Part ?Correlation analysis between IL-22 gene and glycolysis-related genes in colon cancer tissuesObjective:To study the expressions of interleukin-22(IL-22)and glycolysis-related genes and the correlation analysis between them in colon cancer tissues.Material and methods:The distribution of high metabolism was detected by PET-CT in colon cancer patients.The colon cancer tissues were grinded and centrifuged at 4?,and the levels of lactic acid were detected in the supernatant.mRNA was extracted from sediments and RT-PCR was used to measure the expression levels of IL-22 and glycolysis-related genes in colon cancer tissues.The colon cancer tissues were cut into single cell suspension,and the phenotype and cytokine expression were analyzed by flow cytometry.The levels of IL-22 in peripheral blood of patients with colon cancer and healthy volunteers were tested by ELISA.Correlation analysis of IL-22 gene and glycolysis-related genes in colon cancer was conducted by Pearson correlation analysis.Results:The results of PET-CT showed that the metabolic activity of tumor location was significantly higher than that in non-tumor tissues in patients with colon cancer.The level of lactic acid in tumor tissue was significantly higher than that in non-tumor tissues(1 vs.1.3,p=0.005).The results of RT-PCR showed that the expressions of inflammatory factor IL-22 gene and glycolysis-related genes in tumor tissue were significantly higher than that in non-tumor tissue of patient with colon cancer.The results of flow cytometry showed that IL-22 in colon cancer tissue was higher than that in non-tumor tissue.ELISA detection showed that the level of IL-22 in peripheral blood of patients with colon cancer was higher than that in normal people(8.8pg/ml vs.10.3pg/ml,p=0.058).Pearson correlation analysis showed that the gene expression of IL-22 and hexokinase-2 in colon cancer tissue was positively correlated(R=0.768,p<0.001).Conclusions:The level of glycolysis in colon cancer cells was higher than that in non-tumor tissues,with increased expression levels of IL-22 gene and glycolysis-related genes in tumor tissue.The gene expression of IL-22 and hexokinase-2 in colon cancer tissue was positively correlated.Part ?Interleukin-22 promotes aerobic glycolysis via targeting hexokinase-2 in colon cancer cellsObjective:To study the effect of interleukin-22(IL-22)on aerobic glycolysis and the underlying mechanism in colon cancer cells.Material and methods:Glucose consumption and lactate production were detected in the culture supernatant of colon cancer cell by using a glucose assay kit or a lactate assay kit.The mRNA expression of IL-10R2,IL-22R1,c-Myc and hexokinase-2(HK2)were measured by RT-PCR in colon cancer cells.Qualitative analysis of protein expression of IL-22R1,c-Myc and HK2 was conducted by immunofluorescence.The protein expressions of STAT3,c-Myc,HIF-1 and glycolysis-related genes were detected by Western Blot in colon cancer cells.Small interfering RNA(siRNA)and small molecule inhibitor Stattic were used to inhibit the expression of c-Myc,HIF-1 and STAT3 phosphorylation,respectively.Results:The mRNA expressions of IL-10R2 and IL-22R1 gene were detected in all colon cancer cell lines,but there was no expression of IL-22R1 in the T cell line Jurkat.The glucose consumption and lactate production in the supernatant of colon cancer cells administrated with IL-22 were significantly higher than those in the control group.IL-22 promoted the mRNA and protein expression of HK2 in colon cancer cells,and there was no effect on the protein expressions of other metabolic enzymes.At the same time,IL-22 promoted the activation of STAT3 and overexpression of c-Myc.Silencing of HK2 gene by siRNA could significantly inhibit the enhanced aerobic glycolysis induced by IL-22 in colon cancer cells.Knockdown of c-Myc gene decreased IL-22-induced overexpression of HK2.Small molecule inhibitor Stattic can significantly inhibit the phosphorylation of STAT3 and decrease the overexpression of c-Myc and HK2 induced by IL-22 in colon cancer cells.Conclusions:IL-22 promotes aerobic glycolysis by targeting HK2 via STAT3/c-Myc signaling pathway in the colon cancer cells.Part ?The increased aerobic glycolysis induced by interleukin-22 is involved in proliferation in colon cancer cells Objective:To study the effect of interleukin-22 on proliferation and the underlying mechanism in colon cancer cells.Material and methods:Cell proliferation was tested by CCK-8 Assay Kit.The expression of Bcl-2 protein in IL-22-treated group and control group was detected by Western Blot.Small interfering RNA(siRNA)was used to silence hexokinase-2(HK2)gene to verify the effect of IL-22 on proliferation in colon cancer cells.The effect of exogenous IL-22 on the growth of colon cancer was performed in nude mice.The protein expressions of c-Myc and HK2 were detected by immunohistochemistry in colon tumor.Results:Cell proliferation assay showed that IL-22 could significantly promote the proliferation of colon cancer cells.The results of Western Blot showed that the expression of Bcl-2 protein in colon cancer cells treated with IL-22 was significantly higher than that in control group.Knockdown of HK2 protein can inhibit the proliferation of colon cancer cells and the increased protein expression of Bcl-2.IL-22 promoted tumor growth and protein expression of c-Myc and HK2 in tumor in nude mice.Conclusions:The increased aerobic glycolysis induced by interleukin-22 may be involved in proliferation in colon cancer cells.