[Effects of ubiquitin-specific proteases 2-69 on proliferation of breast cancer cells]

Objective: To investigate the expression and significance of ubiquitin-specific proteases 2-69(USP2-69) in invasive ductal carcinoma of breast. Methods: Twenty-four cases of human breast tissue with invasive ductal carcinoma diagnosed at Huanshan Hospital, Fudan University from 2013 to 2015 were collected, and the expression of USP2-69 mRNA and protein was detected by molecular hybridization, Western blot and immunohistochemistry. USP2-69 was over-expressed in cultured human breast cancer cell line MCF-7 by USP2-69 plasmid transfection. The cellular proliferative activity was investigated in vitro. Results: The USP2-69 mRNA and protein were highly expressed in breast invasive ductal carcinoma, compared to adjacent normal tissues (P<0.01). Ki-67 protein expression was also increased in cases with high USP2-69 protein level. Western blot showed significantly higher USP2-69 protein level in cancer tissue compared to the adjacent normal tissue. In the cultured tumor cells, there was increased S phase fraction, cellular proliferation rate, flat positive clones, cyclin D1 expression and decreased p27 expression in USP2-69-transfected MCF-7 cells. Conclusions: USP2-69 is over-expressed in breast invasive ductal carcinoma, and is closely related to proliferation promoting effects. The data provide an important experimental basis for further study on the molecular mechanism of breast cancer cell proliferation.

[Ki-67 expression and its effect on response to neo-adjuvant chemotherapy in invasive breast cancer]

Objective: To investigate the response to neoadjuvant chemotherapy (NAC) among different molecular subtypes of breast cancers using molecular classification with Ki-67 (ER+ PR+ HER2+ Ki-67) or without Ki-67 (ER+ PR+ HER2). Methods: One hundred and twenty-seven cases of invasive breast cancer confirmed by core needle biopsy before NAC were collected from January 2007 to December 2009 and diagnosed at West China Hospital, Sichuan University. The cases were classified into different molecular subtypes using molecular classifications with or without Ki-67. Their clinical and pathological response to NAC was evaluated and compared. Results: The different subtypes using both molecular classifications showed significant difference in clinical response(with Ki-67: χ(2)=22.40, P<0.01; without Ki-67: χ(2)=9.202, P=0.027)but not pathological(P>0.05) response to NAC. By multivariate analysis, Ki-67 was predictive for a clinical complete response (P=0.041) and clinical overall response (P<0.01); also Ki-67 was the only clinicopathological factor predictive of pathological response(P=0.041). Conclusion: The molecular classification with Ki-67 is better to predict breast cancers responsiveness to NAC than the molecular classification without Ki-67.

HDAC1 Expression in Invasive Ductal Carcinoma of the Breast and Its Value as a Good Prognostic Factor

Background

Histone deacetylase 1 (HDAC1) is associated with the expression and function of estrogen receptors and the proliferation of tumor cells, and has been considered a very important factor in breast tumor progression and prognosis. Several studies have reported an association between HDAC1 expression and poorer prognosis in cancers including breast cancer, with a few exceptions. However, because of the dearth of studies on HDAC1 expression in breast cancer, its significance for breast cancer prognosis has not been well defined. Therefore, we examined HDAC1 expression in invasive ductal carcinoma (IDC), the most common breast cancer, and investigated its potential prognostic significance.

Methods

We used 203 IDC tissue samples. Immunohistochemical stains for HDAC1 and real-time polymerase chain reaction for HDAC1 mRNA were performed and the results were compared to generally well-established prognostic factors in breast cancer and patient survival rates.

Results

HDAC1 expression was significantly reduced in proportion to higher histologic grade, higher nuclear pleomorphism score, and higher mitotic counts, and with lower estrogen receptor expression. Furthermore, it was significantly associated with the survival rate.

Conclusions

HDAC1 expression is a good prognostic indicator in IDC.