Intervention Effect Of Euphorbia Humifusa On Colitis-associated Colon Cancer And Its Possible Mechanism

Background Colorectal cancer is one of the malignant tumors of the digestive system,and the incidence of colorectal cancer in China has been increasing in recent years.The incidence of colon cancer is closely related to People’s Daily life and its risk factors.Therefore,it is very important to actively conduct early intervention treatment for high risk factors or precancerous lesions of the colorectum.Objective to explore the intervention effect of Euphorbia humifusa on colitis-associated colorectal cancer induced by AOM/DSS in mice and its possible molecular mechanism.Methods(1)Establishment of colitis-associated colorectal cancer model: first,through a single intraperitoneal injection of azoxymethane(AOM)12.5mg/kg,after 6 days of normal diet and drinking water,the normal drinking water was changed into 2% dextran sodiumsulfate(DSS)drinking water for 6 days,and then 14 days of normal drinking water was given after the end of DSS drinking water,and a round of DSS drinking water was completed.The cycle was repeated for 3 rounds,and the mice in each group continued to feed normal diet and drinking water until the establishment of entire colitis-associated colorectal cancer was completed on the 91 st day.During the modeling period,the active degree,stool condition,body weight,food intake and drinking water of mice were observed.(2)Intervention effect of Euphorbia humifusa(Eu H)colitis-associated Colorectal Cancer induced by AOM/DSS:forty mice were randomly divided into 4 groups,Normal control group,AOM/DSS group,low dose of Euphorbia-humifusa 50mg/kg(L-Eu H)group and high dose of Euphorbia-humifusa150mg/kg(H-Eu H).Except for the normal control group,AOM/DSS group,L-Eu H group,H-Eu H group were chemically induced by AOM/DSS.After the first DSS drinking water,the drug was given by intragastric administration until the end of the experiment.The normal group and AOM/DSS group were given normal saline intragastric administration.(3)Methods:The length of colon and rectum of mice in each group was measured and the number of tumors visible to the naked eye was calculated,Hematoxylin-eosin(HE)was used to stain the colorectal epithelium of mice in each group,and the histopathology was observed under microscope;Reverse transcription quantitative polymerase chain reaction(q RT-PCR)was used to detect the expression of colitis-related genes such as IL-1b,IL-17,IL-6 and TLR4 in colorectal tissues of mice in each group;q RT-PCR was used to detect the expression of endoplasmic reticulum stress related genes CHOP,ATF4,Xbp1 s and MYC in colorectal tissues of mice in each group;q RT-PCR was used to detect the expression of tumor-related genes VEGF,BCL2,PDGF-b and MYC in colorectal tissues of mice in each group;q RT-PCR was used to detect the expression level of miR-17-5p and STAT3 in colorectal tissues of mice in each group;Western blotting(WB)was used to detect the expression of p-STAT3 in colorectal tissues of mice in each group.Results(1)An animal model of colitis-related colorectal cancer was successfully established by AOM/DSS.The weight loss of AOM/DSS group was obvious,soft stool,thin stool and even bloody stool,and anal prolapse of some mice in the later stage.The colon shortened obviously,and the formation of tumor was visible to the naked eye;HE showed the formation of a large number of heteromorphic cells,hyperchromatic nuclei,increased nucleo-cytoplasm ratio,and disordered colonic gland structure.(2)Compared with the normal control group,the expression of inflammatory factors IL-1b,IL-17,IL-6 and TLR4 increased in AOM/DSS group,and the expression level of inflammatory factors in Eu H group was significantly lower than that in AOM/DSS group.(3)Compared with the normal control group,the expression level of endoplasmic reticulum stress-related genes ATF4,CHOP and Xbp1 s in AOM/DSS group was significantly increased,and the expression level of endoplasmic reticulum stress-related genes in Eu H group was significantly lower than that in AOM/DSS group.(4)Compared with the normal control group,the expression of tumor-related genes VEGF,PDGF-b,BCL2 and MYC in colorectal tissue of AOM/DSS group showed an upward trend,and the expression level of tumor-related genes in Eu H group was significantly lower than that in AOM/DSS group.(5)Compared with the normal control group,the expression of miR-17-5p in colorectal tissue of AOM/DSS group decreased and increased in Eu H group,while the expression of STAT3 in colon tissue of AOM/DSS group was higher than that of Eu H group,while the expression of STAT3 was significantly lower in Eu H group.(6)The expression of p-STAT3 protein was high in AOM/DSS group and low in Eu H intervention group.Conclusion(1)The animal model of colitis-related colorectal cancer was successfully established.Eu H has a positive intervention effect on colitis-related colon cancer.The possible mechanism is that Eu H exerts its anti-tumor effect by regulating the STAT3 signal pathway mediated by miR-17-5p.It is mainly manifested in that Eu H plays a role by inhibiting the expression of colitis-related genes,endoplasmic reticulum stress-related genes and tumor-related genes.