Objective To review the mechanisms of breast cancer escaping from host immune surveillance. Methods The current literatures on the mechanisms of breast cancer cells escaping from host immune surveillance were reviewed in the following aspects: alterations of MHC-Ⅰmolecule phenotype, deficiency of costimulatory molecules, apoptosis of T-lymphocytes induced by breast cancer cells presenting Fas ligand (FasL) and TNF-related apoptosis-inducing ligand (TRAIL) and host immune tolerance induced by tumor cells. Results Loss of classical antigen-presenting human leukocyte antigen (HLA) class-Ⅰmolecules, expression of non-classical HLA class-ⅠmoleculesHLA-G, loss of costimulatory molecule B7, apoptosis of T-lymphocytes induced by tumor cells presenting FasL and TRAIL and antigen-inducing host immune tolerance were related to breast cancer escaping from immune surveillance. Conclusion Breast cancer cells escape from host immune surveillance by altering MHC-Ⅰmolecules, lacking of costimulatory molecules, inducing of apoptosis of T cells and host immune tolerance. But the factors resulting in breast cancer escaping from host immune surveillance are not yet clear and should be further studied.

Objective To investigate the expression of Epstein-Barr virus(EBV)-latent membrane protein 1 (LMP1) in chronic atrophic gastritis (CAG) with intestinal metaplasia and discuss its effect on gastric cancer.Methods Immunohistochemistry was used to examine the expression of EBV-LMP1 in 45 cases of chronic superficial gastritis(CSG),63 cases of CAG with intestinal metaplasia and 36 cases of gastric cancer.Results There was no expression of EBV-LMP1 in CSG and gastric cancer,while the positive rate of EBV-LMP1 in CAG with intestinal metaplasia was 36.5％ (23/63) and EBV-LMP1 was mainly stained in the cell nucleus.The expression of EBV-LMP1 in CAG with intestinal metaplasia was significantly higher than that in CSG and gastric cancer,and there was significant difference (P =0.000).Conclusions EBV-LMP1 is expressed in CAG with intestinal metaplasia.The expression of EBV-LMP1 is significantly higher than that in CSG and gastric cancer indicating that EBV infection in gastric carcinogenesis may play an important role in the early stages.

Objective To investigate whether TG2 promotes drug resistance to epirubicin through AKT signal pathway in breast cancer. Methods MCF-7 cells with constant expression of TGM2 gene(TGM2-LV)were established via the lentiviral vector. The breast cancer cells were divided into five groups,including the NC group, TG2 group and MK2206 group. The MCF-7/adr cells were divided into ADR group and MKadr group. The expres-sion of TG2 ,AKT ,Bcl-2 and P53 was detected by Western blot assay. Cells were treated with epirubicin. MTT assay was performed to assess cell proliferation. The inhibition ratio of cancer cell proliferation was evaluated. TUNEL analysis was performed to identify the apoptosis of the breast cancer cells. Results Lvels of TG2,p-AKT and Bcl-2 in NC group were significantly lower than those in TG2 group,while the expression of P53 in NC group was much higher. In MK2206(or MK/adr )group,p-AKT and Bcl-2 were down-regulated,while P53 was markedly up-regulated compared with TG2(or ADR)group(P<0.05). The results of the MTT assay showed a strong inhibi-tion in cell proliferation rate in MK2206(or MKadr )group. Compared with the NC group,TG2 promoted prolifera-tion of MCF-7 cells in TG2 group. The cell apoptosis rate in MK2206(or MKadr )group was significantly higher than that in TG2(or ADR)group(P<0.05). TG2 significantly inhibit the apoptosis of breast cancer cells ,com-pared to the control group. Conclusion TG2 might promote drug resistance to epirubicin through AKT signal path-way in breast cancer

Objective:To investigate whether prophylactic use of metal clips is necessary after cold snare polypectomy (CSP) of colorectal polyps of 6-10 mm.Methods:A total of 200 patients with 6-10 mm polyps that met the criteria of cold snare resection in Chengdu Third People's Hospital from 15 February 2022 to 30 May 2022 were randomly divided into two groups: a group that received preventive metal clip treatment and an observation group. Age, gender, body mass index (BMI), Boston score, endoscopy entry time, wound size, operation time, intraoperative bleeding time, postoperative delayed bleeding rate and cost between the two groups were compared and analyzed.Results:Ninety-eight patients in the metal clip group had 122 polyps removed, and 97 patients in the observation group had 119 polyps removed. There was no significant difference in the age, gender, BMI, Boston score, endoscopy entry time or wound size between the two groups. There were significant differences in the operation time (171.03±90.78 s VS 69.81±43.26 s, t=2.266， P=0.010), intraoperative bleeding time (19.98±17.37 s VS 29.16±17.56 s, t=-2.875， P=0.006) and surgery cost (571.63±110.92 yuan VS 366.32±13.2 yuan, t=18.102， P<0.001) between the metal clip group and the observation group. There was no significant difference in the delayed bleeding incidence［0.0%（0/98）VS 1.0%（1/97）， P=0.497］between the two groups. Conclusion:For patients with continuous bleeding time <60 seconds after CSP of 6-10 mm colonic polyps, the prophylactic use of metal clips may reduce the bleeding time, but may increase the operation time and cost. Metal clips have little effect on preventing postoperative complications.