BackgroundIn 2014, breast cancer remains a major cause of mortality worldwide mostly due to tumor relapse and metastasis. There is currently a great interest in identifying cancer biomarkers and signalling pathways mechanistically related to breast cancer progression. Matrix metalloproteinase-9 (MMP-9) is a member of matrix degrading enzymes involved in cancer development, invasion and metastasis. Our objective was to investigate MMP-9 expression in normal human breast tissue and to compare it to that of breast cancer of various histological grades and molecular subtypes. We also sought to correlate MMP-9 expression with the incidence of metastasis, survival rates and relapse in breast cancer patients.MethodsMMP-9 was first studied using in silico analysis on available DNA microarray and RNA sequencing data of human breast cancer tissues and human breast cancer cell lines. We next ascertained MMP-9 expression in both normal breast tissue and in human breast carcinoma tissue microarrays.ResultsSignificant increase in MMP-9 expression was found in breast cancer cells where compared to normal breast tissue. A positive correlation could also be established between elevated levels of MMP-9 and breast cancer of high histological grade. Furthermore, our results indicate that not only MMP-9 is differentially expressed between each molecular subset but also, more importantly MMP-9 overexpression revealed itself as a startling feature of triple-negative and HER2-positive breast cancers. Lastly, the clinical relevance of MMP-9 overexpression is strongly supported by its significant association with a higher incidence of metastasis and relapse.ConclusionsDifferential expression of MMP-9 reflects the extent of cellular differentiation in breast cancer cells and is closely related to the most aggressive subtypes of breast cancer. Hence, MMP-9 is a promising prognostic biomarker of high-grade breast cancer. In our opinion, MMP-9 expression could help segregate subsets of aggressive breast cancer into clinically meaningful subtypes.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2407-14-609) contains supplementary material, which is available to authorized users.

Breast cancer is a heterogeneous disease comprising the estrogen receptor (ER)–positive luminal subtype which is subdivided into luminal A and luminal B and ER-negative breast cancer which includes the triple-negative subtype. This study has four aims: 1) to examine whether Minichromosome Maintenance (MCM)2, MCM4, and MCM6 can be used as markers to differentiate between luminal A and luminal B subtypes; 2) to study whether MCM2, MCM4, and MCM6 are highly expressed in triple-negative breast cancer, as there is an urgent need to search for surrogate markers in this aggressive subtype, for drug development purposes; 3) to compare the prognostic values of these markers in predicting relapse-free survival; and 4) to compare the three approaches used for scoring the protein expression of these markers by immunohistochemistry (IHC). MCM2, MCM4, MCM6, and MKI67 mRNA expression was first studied using in silico analysis of available breast cancer datasets. We next used IHC to evaluate their protein expression on tissue microarrays using three scoring methods. MCM2, MCM4, and MCM6 can help in distinction between luminal A and luminal B whose therapeutic management and clinical outcomes are different. MCM2, MCM4, MCM6, and Ki-67 are highly expressed in breast cancer of high histological grades that comprise clinically aggressive tumors such as luminal B, HER2-positive, and triple-negative subtypes. Low transcript expression of these markers is associated with increased probability of relapse-free survival. A positive relationship exists among the three scoring methods of each of the four markers. An independent validation cohort is needed to confirm their clinical utility.

Breast cancer is a heterogeneous disease comprising a diversity of tumor subtypes that manifest themselves in a wide variety of clinical, pathological, and molecular features. One important subset, luminal breast cancers, comprises two clinically distinct subtypes luminal A and B each of them endowed with its own genetic program of differentiation and proliferation. Luminal breast cancers were operationally defined as follows: Luminal A: ER+, PR+, HER2-, Ki-67<14% and Luminal B: ER+ and/or PR+, HER2-,Ki-67≥14% or, alternatively ER+ and/or PR+, HER2+, any Ki-67. There is currently a need for a clinically robust and validated immunohistochemical assay that can help distinguish between luminal A and B breast cancer. MCM2 is a family member of the minichromosome maintenance protein complex whose role in DNA replication and cell proliferation is firmly established. As MCM2 appears to be an attractive alternative to Ki-67, we sought to study the expression of MCM2 and Ki-67 in different histological grades and molecular subtypes of breast cancer focusing primarily on ER-positive tumors. MCM2 and Ki-67 mRNA expression were studied using in silico analysis of available DNA microarray and RNA-sequencing data of human breast cancer. We next used immunohistochemistry to evaluate protein expression of MCM2 and Ki-67 on tissue microarrays of invasive breast carcinoma. We found that MCM2 and Ki-67 are highly expressed in breast tumors of high histological grades, comprising clinically aggressive tumors such as triple-negative, HER2-positive and luminal B subtypes. MCM2 expression was detected at higher levels than that of Ki-67 in normal breast tissues and in breast cancers. The bimodal distribution of MCM2 scores in ER+/HER2- breast tumors led to the identification of two distinct subgroups with different relapse-free survival rates. In conclusion, MCM2 expression can help sorting out two clinically important subsets of luminal breast cancer whose treatment and clinical outcomes are likely to diverge.

The aim of this study was to examine the impact of maternal education on child immunization uptake in Pakistan, both at individual and community levels. Pakistan Demographic and Health Survey data were used for analysis. Multilevel logistic regression was used to access the individual- and community-level factors associated with childhood immunization coverage. Out of 6765 children 2659 (39.3%) were fully immunized. Parents education, access to media, and wealth status have positive while ethnicity and working status of mother have a negative impact on the immunization uptake. In the community with a high percentage of educated mothers, the odds of immunized children were high (odds ratio = 1.43, 95% confidence interval = 1.14-1.80) as compared with communities with lower percentage of educated mothers. Moreover, significant variation was found in the likelihood of full immunization across communities. Both community- and individual-level factors have substantial impact on children immunization status. There is a need of improvement in maternal education, poverty alleviation, and removal of rural-urban disparities.

Ephrin B2 (EFNB2) is a ligand for erythropoietin-producing hepatocellular kinases (EPH), the largest family of receptor tyrosine kinases. It has critical functions in many biological systems, but is not known to regulate blood pressure. We generated mice with a smooth muscle cell (SMC)-specific deletion of EFNB2 and investigated its roles in blood pressure regulation and vascular SMC (VSMC) contractility. Male Efnb2 knockout (KO) mice presented reduced blood pressure, whereas female KO mice had no such reduction. Both forward signaling from EFNB2 to EPHs and reverse signaling from EPHs to EFNB2 were involved in regulating VSMC contractility, with EPHB4 serving as a critical molecule for forward signaling, based on crosslinking studies. We also found that a region from aa 313 to aa 331 in the intracellular tail of EFNB2 was essential for reverse signaling regulating VSMC contractility, based on deletion mutation studies. In a human genetic study, we identified five SNPs in the 3′ region of the EFNB2 gene, which were in linkage disequilibrium and were significantly associated with hypertension for male but not female subjects, consistent with our findings in mice. The coding (minor) alleles of these five SNPs were protective in males. We have thus discovered a previously unknown blood pressure-lowering mechanism mediated by EFNB2 and identified EFNB2 as a gene associated with hypertension risk in humans. European Journal of Human Genetics (2016) 24, 1817-1825; doi:10.1038/ejhg.2016.105; published online 17 August 2016 INTRODUCTION Erythropoietin-producing hepatocellular kinases (EPH) are the largest family of receptor tyrosine kinases. In the basis of sequence homology, they are divided into A and B subfamilies. 1 Their ligands, called ephrins (EFNs), are also cell surface molecules. 2 EFNs are also divided into A and B subfamilies, based on the way they anchor on the cell surface: the A subfamily anchors on the cell surface through glycophosphatidylinositol, and the B subfamily, through a transmembrane domain. 2 The interactions between EPH kinases and EFNs are promiscuous, but EPHA kinases preferably interact with EFNA ligands, and EPHB kinases with EFNB ligands, which have three members, EFNB1, EFNB2 and EFNB3. 2 Although EPH members and EFN members share homology with their respective members, each member has its distinct function in different cellular processes. [3][4][5][6][7] In general, the EPH kinases interact with their EFN ligands on neighboring cells, because EPHs and EFNs are all cell surface molecules. 2 These molecules could be cleaved from the cell surface by enzymes such as ADAM10, 8,9 an unspecified matrix metalloproteinase, 10 or γ-secretase; 11 therefore, it is possible that the shed soluble fragments of EPH and EFN might be able to influence cells and tissues at a distance by blocking the interaction of EPHs and EFNs there.