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LDH-A, as the critical enzyme accounting for the transformation from pyruvate into lactate, has been demonstrated to be highly expressed in various cancer cells and its silencing has also been approved relating to increased apoptosis in lymphoma cells. In this study, we intend to investigate the correlation between LDH-A and other clinicopathological factors of breast cancer and whether LDH-A silencing could suppress breast cancer growth, and if so the potential mechanisms. 46 breast cancer specimens were collected to study the relation between LDH-A expression and clinicopathological characteristics including menopause, tumor size, node involvement, differentiation, and pathological subtypes classified by ER, PR, and Her-2. shRNAs were designed and applied to silence LDH-A expression in breast cancer cell lines MCF-7 and MDA-MB-231. The effects of LDH-A reduction on cancer cells were studied by a series of in vitro and in vivo experiments, including cell growth assay, apoptosis evaluation, oxidative stress detection, transmission electron microscopy observation, and tumor formation assay on nude mice. LDH-A expression was found to correlate significantly with tumor size and to be independent for other clinicopathological factors. LDH-A reduction resulted in an inhibited cancer cell proliferation, elevated intracellular oxidative stress, and induction of mitochondrial pathway apoptosis. Meanwhile, the tumorigenic ability of LDH-A deficient cancer cells was significantly limited in both breast cancer xenografts. The Ki67 positive cancer cells were significantly reduced in LDH-A deficiency tumor samples, while the apoptosis ratio was enhanced. Our results suggested that LDH-A inhibition might offer a promising therapeutic strategy for breast cancer.

Rapid IκBα turnover has been implicated in the high basal NF-κB activity in WEHI 231 B immature IgM+ B cells. Here we show that treatment of WEHI 231 cells with apigenin, a selective inhibitor of the protein kinase CK2, decreased the rate of IκBα turnover and nuclear levels of NF-κB. Turnover of IκBα in these cells is mediated in part by the protease calpain. Since both CK2 and calpain target the proline-glutamic acid-serine-threonine (PEST) domain, we investigated the role of CK2 in the degradation of IκBα by calpain using an in vitro phosphorylation/degradation assay. CK2 phosphorylation enhanced μ-calpain-mediated degradation of wild-type IκBα, but not of mutant 3CIκBα, with S283A, T291A, and T299A mutations in phosphorylation sites within the PEST domain. Roles for CK2 and calpain in IκBα turnover were similarly shown in CH31 immature and CH12 mature IgM+ B cells, but not in A20 and M12 IgG+ B cells. These findings demonstrate for the first time that CK2 phosphorylation of serine/threonine residues in the PEST domain promotes calpain-mediated degradation of IκBα and thereby increases basal NF-κB levels in IgM+ B cells.

BackgroundInterprofessional learning is gaining momentum in revolutionizing healthcare education. During the academic year 2015/16, seven undergraduate-entry health and social care programs from two universities in Hong Kong took part in an interprofessional education program. Based on considerations such as the large number of students involved and the need to incorporate adult learning principles, team-based learning was adopted as the pedagogy for the program, which was therefore called the interprofessional team-based learning program (IPTBL). The authors describe the development and implementation of the IPTBL program and evaluate the effectiveness of the program implementation.MethodsEight hundred and one students, who are predominantly Chinese, participated in the IPTBL. The quantitative design (a pretest-posttest experimental design) was utilized to examine the students’ gains on their readiness to engage in interprofessional education (IPE).ResultsThree instructional units (IUs) were implemented, each around a clinical area which could engage students from complementary health and social care disciplines. Each IU followed a team-based learning (TBL) process: pre-class study, individual readiness assurance test, team readiness assurance test, appeal, feedback, and application exercise. An electronic platform was developed and was progressively introduced in the three IUs. The students’ self-perceived attainment of the IPE learning outcomes was high. Across all four subscales of RIPLS, there was significant improvement in student’s readiness to engage in interprofessional learning after the IPTBL. A number of challenges were identified: significant time involvement of the teachers, difficulty in matching students from different programs, difficulty in making IPTBL count towards a summative assessment score, difficulty in developing the LAMS platform, logistics difficulty in managing paper TBL, and inappropriateness of the venue.ConclusionsDespite some challenges in developing and implementing the IPTBL program, our experience showed that TBL is a viable pedagogy to be used in interprofessional education involving hundreds of students. The significant improvement in all four subscales of RIPLS showed the effects of the IPTBL program in preparing students for collaborative practice. Factors that contributed to the success of the use of TBL for IPE are discussed.Electronic supplementary materialThe online version of this article (10.1186/s12909-017-1046-5) contains supplementary material, which is available to authorized users.