The Correlation Of TIPE3 Expression In Colorectal Cancer With Tumor Immune Infiltration And The Prognosis Of Patients

BackgroundColorectal cancer（CRC）is the most common digestive malignancy and one of the leading causes of death in all tumor-related cases.In 2020,there will be 19.3 million new cancer cases worldwide and nearly 10 million cancer deaths,of which there were more than 1.9 million new cases of CRC and 935,000 deaths,accounting for about 1 in 10 new cases and deaths from cancer rank third and second in morbidity and mortality.CRC is one of the most common malignant tumors in my country.In 2020,there were 555,000 new cases,ranking third among all tumors,and 286,000 deaths ranked fifth,an increase of 43%and 53%,respectively,compared with 2015.In general,the incidence is higher in men than in women.TIPE3 belongs to the Tumor necrosis factor α-induced protein 8（TIPE）family.TIPE3 was first reported in 2008 and is the least studied of the four members of the TIPE family.It is induced by TNF-α and is closely related to immune regulation and tumorigenesis.TIPE3 is expressed in most human organs,such as the stomach,lung,prostate,kidney,brain,etc.;it is preferentially expressed in epithelial-derived cells with secretory function and is significantly expressed in lung cancer,esophageal cancer,cervical cancer,and colon cancer.At present,there are few studies on TIPE3,and only some studies have found that TIPE3 can promote the proliferation,migration,and invasion of cancer cells by activating AKT and NF-κB pathways.ObjectiveDue to the lack of specific tumor markers,CRC patients often miss the optimal treatment period when they are diagnosed and have a high recurrence and metastasis rates.Therefore,the early diagnosis of CRC and the discovery of prognostic indicators are crucial for improving the patient’s living environment.This project mainly uses clinical specimens to study the relationship between TIPE3 expression and tumor immune infiltration and prognosis of patients with CRC.To provide ideas for the early diagnosis and prevention of CRC.Methods（1）In the early stage,we used molecular biology methods such as RT-qPCR and Western blot to identify the expression pattern of TIPE3 in cancer tissues and adjacent tissues in CRC patients.（2）Immunohistochemical techniques were used to detect the expression characteristics of TIPE3 in cancer tissues and adjacent tissues of 110 cases of CRC patients;the relationship between the expression of TIPE3 and the clinicopathological factors of patients was analyzed.（3）According to the expression characteristics of TIPE3 and the prognosis data of the patients,the Kaplan-Meier survival curve of the expression level of TIPE3 and the prognosis of the patients was drawn,and the correlation between the expression level of TIPE3 and the prognosis of the patients was analyzed.（4）The correlation between TIPE3 and CD8+T lymphocytes,CD20+B lymphocytes,and CD66b+neutrophils was investigated by immunohistochemistry.（5）Finally,combined with single-cell transcriptome sequencing technology,the immune cells in CRC tissue were subdivided,which further proved the relationship between TIPE3 and tumor immune infiltration.Result（1）RT-qPCR and Western Blot results showed that the expression of TIPE3 was upregulated in CRC tissues,and was significantly higher than that in adjacent tissues.（2）Immunohistochemical results showed no significant correlation with clinicopathological factors.（3）The Kaplan-Meier survival curve of TIPE3 expression level associated with patient prognosis showed that the overall survival time of patients with low expression of CRC with high TIPE3 expression was significantly shortened and the prognosis was poor.（4）The immune infiltration correlation showed that the expression of TIPE3 was negatively correlated with the number of CD8+T cells and CD20+B cells;it was positively correlated with the number of CD66b+neutrophils,especially CD66b+neutrophils.significantly higher than other cases.（5）The results of single-cell RNA sequencing showed that samples with low expression of TIPE3 had an up-regulated number of CD8+T cells and a better prognosis,which was consistent with the results of immunohistochemistry.ConclusionThe expression of TIPE3 in CRC tissues is correlated with tumor immune cell infiltration:For the patients,which TIPE3 high expression with less CD8+T cells and CD20+B cells,more CD66b+neutrophils;TIPE3 low expression with more CD8+T cells and CD20+B cells,more CD66b+neutrophils.CRC patients with high TIPE3 expression have a poor prognosis.TIPE3 is expected to be used as a target for the treatment and prevention of CRC and has a significant prompting effect on the prognosis of patients.