Effect Of NK Cells On Immune Escape Mechanism In Cervical Cancer

Objectives:In the background of HR-HPV infection,the expression level of NKp30 and NKp46 in local cervical tissues of patients with continuous HR-HPV infection and different levels of cervical lesions was studied,and its significance was further explored to understand the changes of immune function in the occurrence and development of cervical cancer.Methods and materials:A total of 110 cases of cervical tissue from patients who visited the outpatient department of gynaecology of The Second Hospital of Tianjin Medical University and further were treated with colposcope cervical biopsy or inpatient surgery from January 1,2018 to December 30,2018 were selected.Among them,there were 20 cases in the normal group(both TCT and HPV tests were negative),20 cases in the transient HR-HPV infection group(HR-HPV infection was cleared at 6-12 months),20 cases in the continuous HR-HPV infection group(HR-HPV remained uncleared after 6-12 months of infection),20 cases in the LSIL group,20 cases in the HSIL group,and 10 cases of SCC group.No special treatment such as chemotherapy or radiotherapy was performed before the specimens were collected.All pathological specimens were confirmed by 2 senior pathologists,and the expression of NK cells and NKp30,NKp46 in local cervical tissues were detected by immunohistochemical continuous section.Results:1.With the progress of the disease,the number of NK cells in cervical tissues of patients in each group showed a gradually decreasing trend,among which the difference between normal group,persistent HR-HPV infection group and the lesion group was statistically significant,while that between the transient HR-HPV infection group and the lesion group was statistically significant.At the same time,the difference between the lesion group and the cervical cancer group was statistically significant.2.With the progression of the disease,the expression of Natural cytotoxicity receptor NKp30 in cervical tissues of each group showed a downward trend.The expression of NKp30 in the HSIL group and cervical cancer group showed a significant decline.The difference between the normal group and the lesion group was statistically significant.At the same time,the difference between the transient HR-HPV infection group and the lesion group also was significant.The difference between the lesion group and the cervical cancer group was statistically significant.3.With the progression of the disease,the expression of NK cell surface-activated receptor NKp46 in cervical tissues of patients in each group also showed a gradually decreasing trend,and the difference between the normal group,transient HR-HPV infection,persistent HR-HPV infection group and the lesion group was statistically significant.There was no significant difference in pairwise comparison between the lesion groups.Conclusions:The number of NK cells infiltrating into local cervical tissues and the expression level of NKp30,NKp46 in lesion group were significantly lower than those in the normal group which suggested that patients of lesion group were under immunosuppression.NK cells may be involved in the immune escape during the development of cervical cancer,which is mediated by the decline of the surface active receptor NKp30 NKp46,but the specific mechanism remains to be further studied.The number of NK cells in the persistent HR-HPV infection group was significantly different from that in the normal group,and the expressions of NKp30 and NKp46 showed a downward trend.It suggests that NK cells may be involved in the immune escape process of the body when the body is infected with the virus but has not yet caused cervical lesions,and the local cervical tissue of the body has immune deficiency.