Objective:To study the clinicopathologic characteristics and the prognostic factors of triple negative breast cancer,and to study the correlation between clinicopathologic features and EGFR expression.Methods:Clinical characteristics and prognosis of 200 breast cancer patients diagnosed between 1997 and 2004 were reviewed.The paraffin embedded tissues were selected and tissue microarray blocks were made.Immunohistochemical staining was used to evaluate the expression of ER,PR and HER2 for breast cancer molecular type.EGFR expression was evaluated to analyze its correlation with the clinical characteristics and prognosis.Results:Fourty-two cases(21%)of 200 were triple negative breast cancer(TNBC).There was no significant difference between TNBC and non-TNBC in clinicopathologic parameters such as age,tumor size,clinical stage,and lymph node status.However,there was significant difference in histological category and menostasis status between the two groups(P<0.05).Among TNBC,17 0f 42 died during the follow-up(the overall suivival rate was 59.52%),while 26 0f 158 non-TNBC died(the overall survival rate was 83.54%).EGFR was significantly overexpressed in TNBC(69.05%)and it was associated with lymph node status and histological category.Conclusion:Although the incidence of TNBC is low,it has a poorer prognosis than other subtypes.EGFR is highly expressed in TNBC and may serve as a prognostic index and an important therapatic target for breast cancer.

Objective:To investigate the mechanism of cyclic AMP receptor protein (CRP) in regulating the siderophore enterobactin-related gene entC of carbapenem-resistant Klebsiella pneumoniae (CRKP). Methods:A mutant strain with crp gene deletion strain (Δ crp) and a complementary strain (c-Δ crp) were constructed using CRKP-27 as the wild-type strain. The influence of CRP on the secretion of siderophore by CRKP was analyzed by chrome azurol sulfonate (CAS) quantitative assay. RT-qPCR and lacZ reporter gene fusion assay were used to detect the regulatory effect of CRP on entC gene expression and its promoter. Electric mobility shift assay (EMSA) was performed to detect the binding of CRP to the entC promoter region and the binding sequence was analyzed by DNase Ⅰ footprinting assay. Results:The Δ crp and c-Δ crp strains were successfully constructed. Compared with the wild-type and c-Δ crp strains, the Δ crp strain could secrete more siderophore under both normal and iron-deficient conditions, but the difference was statistically significant only under normal condition ( P<0.05). The relative expression of entC gene at mRNA level was significantly lower in the Δ crp strain than that in the wild-type and c-Δ crp strains under both normal and iron-deficient conditions (both P<0.05). The promoter of entC gene in the Δ crp strain was less active than that in the wild-type and c-Δ crp strains under both normal and iron-deficient conditions (both P<0.05). EMSA showed that with the increase of CRP protein, the distance of entC probe from the positive pole was shortened and blocked. DNase Ⅰ footprinting assay further identified the specific binding site of the entC promoter region to CRP as 5′-AAGGTGATAAATGCGTCTCATTTTCAA-3′. Conclusions:The CRP protein in CRKP could specifically bind to the entC promoter region and directly promote its expression at transcriptional level.

Objective:To investigate the mechanism by which Fusobacterium nucleatum ( Fn) infection promotes TNF-α-induced inflammatory changes in colorectal cancer HCT116 cells. Methods:Fn-infected cells and TNF-α inflammation induction models were established and divided into 4 groups, namely uninfected control group, Fn-infected group, TNF-α induction group, and Fn+ TNF-α group. First, Fn was used to infect normal colonic epithelial cells hcoEPIC, colorectal cancer HCT116 and LoVo cells, the cell adhesion was detected 4 h later. Subsequently, HCT116 cells were induced with TNF-α for 3 h and then infected with Fn. After 24 h, the cell survival rate and cell damage were detected by CCK8 experiment and lactate dehydrogenase (LDH) viability assay. The ELISA method was further used to detect the expression of nuclear transcription factor NF-κB and cytokines IL-6, IL-8, and IL-1β in the cell and cell culture supernatant. Results:Fn has strong adhesion to colorectal cancer cells HCT116 and LoVo ( P<0.05), but basically does not show invasion. On the contrary, it has a higher invasion rate to normal colonic epithelial cells hcoEPIC after 24 h. Compared with the uninfected Fn group, the cell survival rate of the Fn-infected group was significantly reduced and the cell damage increased ( P<0.001). Three hours after TNF-α induction, Fn infection further promoted cell death and damage ( P<0.001). The expression of NF-κB in the Fn infection and TNF-α alone treatment group was significantly higher than that of the uninfected group ( P<0.001, P<0.05), and the NF-κB expression in the Fn+ TNF-α group was significantly higher than that of the control group and the single treatment group ( P<0.001). In the Fn infection and TNF-α treatment groups, the expressions of IL-6 and IL-8 were significantly higher than those in the uninfected group ( P<0.001), and IL-1β did not change significantly ( P>0.05). The expressions of IL-6, IL-8 and IL-1β in the Fn+ TNF-α group were significantly higher than those in the normal control group and the single treatment group ( P<0.05). Conclusions:Fusobacterium nucleatum can preferentially adhere to colorectal cancer cell HCT116, further promote TNF-α-induced cell damage and death, the expression and release of NF-κB and its downstream pro-inflammatory cytokines IL-6, IL-8, IL-1β.