Expression of superoxide dismutase 2 in breast cancer and its clinical significance / 南方医科大学学报

OBJECTIVE@#To evaluate the expression and prognostic value of superoxide dismutase 2 (SOD2) in breast cancer and explore its possible role in the occurrence and progression of breast cancer.@*METHODS@#We performed bioinformatics analysis of the TCGA data for the expression and clinical relevance of SOD2 in patients with breast cancer. Gene enrichment analysis (GSEA) was performed using the KEGG gene set, the protein interaction network was constructed using the STRING database, and the key genes were screened using Cytoscape software. We also collected 60 pairs of primary breast cancer tissue samples and adjacent samples for detecting SOD2 expressions using immunohistochemistry and RT-qPCR and analyzed the correlation of SOD2 expression with the clinicopathological parameters of the patients.@*RESULTS@#The expression of SOD2 was significantly lower in breast cancer tissue than in adjacent tissues with significant correlation with TNM stage and axillary lymph node metastasis ( < 0.05). Kaplan-Meier survival analysis showed that the recurrence-free survival, distant metastasis-free survival (RFS) and post-progressive survival were significantly shorted in patients with high SOD2 expression than in those with low SOD2 expression ( < 0.05). GSEA enrichment analysis indicated that SOD2 played an important role in the JAK-STAT signaling pathway. IL10 and STAT4 were identified as the key genes in the PPI network, and they were both positively correlated with SOD2. In the 60 pairs of clinical samples, SOD2 was highly expressed in breast cancer tissues with close correlation with axillary lymph node metastasis and the expressions of estrogen receptor and androgen receptor ( < 0.05).@*CONCLUSIONS@#The expression of SOD2 in breast cancer is significantly correlated with TNM stage and axillary lymph node metastasis. SOD2 may affect the proliferation, invasion and metastasis of breast cancer cells possibly by regulating IL10 and/or STAT4 to affect the JAK/STAT signaling pathway.

The correlation and significance of gene polymorphisms of C1236T, G2677T/A and C3435T with molecular subtypes of breast cancer / 天津医药

Objective To investigate the distribution of the MDR1 exon12 (C1236T), exon21 (G2677T/A) and exon 26 (C3435T) gene polymorphisms in breast cancer patients, and to analyse their relationship with molecular subtypes of breast cancer. Methods The genotyping of C1236T, G2677T/A and C3435T were detected by polymerase chain reaction (PCR)-high resolution melting (HRM) method in 400 cases of breast cancer. The Hardy-Weinberg equilibrium test was used for ge?netic equilibrium distribution of genotype. The molecular subtypes of breast cancer were classified based on St.Gallen Con?sensus 2013. The genotype distributions of C1236T, G2677T/A and C3435T in breast cancer were analyzed. Their relation?ship with molecular subtypes in breast cancer was analyzed as well. Results ①In 400 cases of breast cancer, there were 2, 3 and 2 specimens did not get genotyping results in C1236T, G2677T/A and C3435T genotype detection. The CC, CT and TT genotypes of C1236T accounted for 16.08% (64/398), 44.22% (176/398) and 39.70% (176/398). GG, GT, GA, TT and AT genotypes of G2677T/A accounted for 16.62%(66/397), 44.33%(176/397), 7.05%(28/397), 27.46%(109/397) and 4.54%(18/397). CC, CT and TT genotypes of C3435T accounted for 21.11%(84/398), 56.03%(223/398) and 22.86%(91/398) re?spectively. Hardy-Weinberg genetic equilibrium testing showed that polymorphisms of C1236T, G2677T/A and C3435T had group representation (P0.05). Conclusion C3435T gene polymor?phism can explain more accurately heterogeneity of breast cancer. CT/TT genotype in different molecular subtypes of breast cancer may be more sensitive to drug treatment.