Objective To study the clinical,pathological features and treatment of metastatic breast cancer with triple negative breast cancer(TNBC) and its relationship with disease free survival.Methods One hundred and fifty-eight cases of TNBC patients who were treated in the First Affiliated Hospital of Zhengzhou University and the Chinese Medicine Hospital of Changge from January 2004 to January 2009 were selected as the research objects.All patients received operation and radiotherapy,the relationship between the clinical characteristics,pathological features and treatment with 5,3 year survival rate,and the recurrence and metastasis of patient were analyzed.Results In clinical stage Ⅲ period,the 3 years survival rate was 46.51％ (20/43),5years survival rate was 37.21％ (16/43),all significantly lower than in the phase Ⅰ and Ⅱ (91.53％ (54/59) and 76.27 ％ (45/59);87.50％ (49/56) and 71.43 ％ (40/56)),and the differences were statistically significant (x2=25.306,15.787,19.348,11.592;P＜0.001).With lymph node metastasis,the 3 years survival rate was 66.00％ (33/50),5 years survival rate was 50.00％ (25/50),significantly lower than that without lymph node metastasis(83.33％ (90/108),70.37％ (76/108)),the difference was statistically significant (x2=5.954,6.150;P＜0.05).In pathological grade Ⅲ,the 3 years survival rate was 65.67％(44/67),5 years survival rate was 43.28％ (29/67),significantly lower than that of grade Ⅰ (92.86％ (26/28),85.71％ (24/28)) and grade Ⅱ (84.13％ (53/63),76.19％ (48/63)),the difference was statistically significant(x2=7.527,14.414,5.839,14.560;P＜0.05).The 3 year survival rate of radiotherapy group was significantly higher than that in non radiotherapy group,the difference was statistically significant (81.58％ (31/38) vs.57.69％ (15/26);x2=4.357,P＜0.05).Patients with metastatic sites were lung,liver,brain,bone and supraclavicular lymph nodes,the median survival time after the transfer all more than 2 years.Conclusion TNBC is a special type of breast cancer that is difficult to treat,no consensus has been reached on the clinical treatment plan.Breast conserving surgery also has certain application value,radiotherapy only can increase the 3 year survival rate.The clinical stage and pathological grade are the influence factors of prognosis.

Objective:To investigate the effect of miR-503 targeting CBX2 on drug resistance of breast cancer MDA-MB-231 cells and its potential mechanism.Methods:miR-con group, miR-503 group, si-con group, two groups of si-chromosome homologues (CBX), anti-miR-con group, anti-miR-503 group, miR-503+pcDNA group, miR-503+pcDNA-CBx2 group were set up. Real-time quantitative fluorescence polymerase chain reaction (qRT-PCR) was used to detect the expression levels of miR-503 and CBX2 mRNA. Western blot was used to detect protein expression. Cell activity was detected by MTT assay. The targeted regulatory relationship was detected by double luciferase assay.Results:Compared with normal breast cells HBL-100 (1.02±0.09), the expression level of miR-503 in breast cancer cells MCF-7 (0.41±0.05), MDA-MB-231 (0.25±0.03) and BT474 (0.35±0.04) was significantly decreased. The expression levels of CBX2 mRNA in MCF-7, MDA-MB-231 and BT474 cells were (4.02±0.35), (4.62±0.36) and (3.47±0.33), respectively. The expression levels of CBX2 protein in MCF-7, MDA-MB-231 and BT474 cells were (0.64±0.07), (0.74±0.05) and (0.68±0.06), respectively. The mRNA and protein contents of CBX2 in normal breast cells HPL-100 were (1.01±0.08) and (0.40±0.04), respectively, and the expression of CBX2 in breast cancer cells was significantly higher than that in normal breast cells ( P<0.05). Overexpression of miR-503 (3.64± 0.30) and silting of CBX2 inhibited proliferation, migration and invasion of MDA-MB-231 cells, and inhibited CBX2 (0.26±0.03), cyclin-dependent kinases, CDK) 4 (0.32± 0.03), Cyclin (CCN) D1 (0.58±0.03), matrix metalloproteinases (matrix metalloproteinases), MMP-2 (0.32±0.03) and MMP-9 (0.32±0.04) ( P<0.05). miR-503 targeted the expression of CBX2, and overexpression of CBX2 (0.75±0.03) could reverse the proliferation and drug resistance of miR-503 to MDA-MB-231 breast cancer cells. Conclusion:miR-503 may inhibit the proliferation, migration and invasion of breast cancer cells by down-regulating the expression of CBX2.

Objective:To investigate the current situation of satisfaction with graduate education among recent medical graduates in China, and analyze the differences between different populations, and to propose countermeasures and suggestions.Methods:From June to July 2023, a self-made questionnaire was used to survey 16 903 medical graduates who had recently earned a post-graduate degree from 78 institutions about their satisfaction with curriculum sessions, practical sessions, research training, tutoring, and institutional management. The degrees of satisfaction with education among different populations were compared through the t test and analysis of variance with the use of SPSS 26.0. Results:The scores of satisfaction of the graduates with tutoring, curriculum sessions, practical sessions, institutional management, and research training were 4.44, 4.03, 4.02, 3.90, and 3.82, respectively. Satisfaction scores for individual dimensions were significantly higher for males, doctors, non-transfers, comprehensive universities, non-agricultural household registration, moderate-to-high annual household income per capita, parents with high educational levels, and parents with mid- or senior-level occupations ( P<0.05). Conclusions:There is room for improvement in students' satisfaction with medical graduate education. To improve the quality of medical graduate education, attention should be paid to key populations, education policies, school management, and tutoring to provide appropriate education for different students.