Interleukin-12 activated CD8+ T cells induces apoptosis in breast cancer cells and reduces tumor growth.

During the past two decades, cytokines have emerged as key molecules to modulate innate and adaptive immunity and mediate anti-tumor activity. Although multiple cytokine types are implicated for such anti-tumor activity in several cancer types, it remains largely unknown in breast cancer. In this study, cytokines that are prior known for antitumor activity in different cancer types were examined against breast cancer using a 4T1 cells based xenograft-model. Our results showed Interleukin-12 (IL-12) (500ng/mouse) significantly suppressed the growth of tumors, while other cytokines showed minimal suppression. Subsequent molecular analysis by flow cytometry and immunohistochemistry confirmed the CD8+ cells infiltration and Interferon-γ (IFN-γ) production by them in tumor environment. In addition, we observed that IFN-γ production by activated CD8+ cells directly induced apoptosis in tumor cells, which together indicate that IL-12 causes CD8+ cells to infiltrate and secrete IFN-γ in tumor environment, which induce apoptosis in them and causes tumor growth suppression. Furthermore, we showed that lower dosage of IL-12 and chemotherapy drug tamoxifen combinations enhanced the tumor suppression as opposed to single treatments, and thereby propose an alternate option for high dosage associated effects for both drug and cytokine treatments.

[Correlation between Tau expression and clinicopathological characteristics of breast invasive ductal carcinomas].

OBJECTIVE: To explore the expression of Tau protein in breast invasive ductal carcinomas and examine the correlation between its expression and clinicopathological characteristics of breast cancer. METHODS: The clinicopathological data of 150 breast cancer patients at Third Municipal Hospital from October 2007 to June 2011 were collected and analyzed. Immunohistochemical method was used to detect the expressions of estrogen receptor (ER), progesterone receptor (PR), HER-2 and Tau protein. RESULTS: No correlations existed between the expression of Tau protein and age, tumor size or node metastasis of breast cancer patients (χ(2) = 0.02, P = 0.88; χ(2) = 0.55, P = 0.46; χ(2) = 1.02, P = 0.31). The expressions of Tau in ER positive patients were significantly higher than ER negative patients. And this trend extended to PR positive and HER-2 negative patients (χ(2) = 15.77, P = 0.00; χ(2) = 5.03, P = 0.03; χ(2) = 8.00, P = 0.01). The expression of Tau protein in Luminal A subtype was significantly higher than in Luminal B subtype, HER-2 over-expression subtype and basal like subtype (χ(2) = 7.26, P = 0.01). CONCLUSIONS: Over-expressed in breast cancer, Tau protein is associated with ER, PR and HER-2. However, the relation between Tau protein and prognosis of breast cancer requires further researches.