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The deletion of exons 9 to 12 of BRCA1 (9–12 del BRCA1) is considered a founder mutation in the Mexican population. We evaluate the usefulness of the target detection of 9–12 del BRCA1 as the first molecular diagnostic strategy in patients with Hereditary Breast and Ovarian Cancer (HBOC). We performed the genetic assessment of 637 patients with suspected HBOC. The region corresponding to the breakpoints for the 9–12 del BRCA1 was amplified by polymerase chain reaction (PCR). An analysis of the clinical data of the carriers and non-carriers was done, searching for characteristics that correlated with the deletion. The 9–12 del BRCA1 was detected in 5% of patients with suspected HBOC (30/637). In patients diagnosed with ovarian cancer, 13 of 30 were 9–12 del BRCA1 carriers, which represents 43%. We found a significant association between the 9–12 del BRCA1 carriers with triple negative breast cancer and high-grade papillary serous ovarian cancer. We concluded that the detection of the 9–12 del BRCA1 is useful as a first molecular diagnostic strategy in the Mexican population. In particular, it shortens the gap in genetic assessment in patients with triple negative breast cancer and ovarian cancer. [ABSTRACT FROM AUTHOR]

The article explores the impact of fluoroquinolone (FQ) antibiotics on tendon healing in a rat rotator cuff healing. Topics discussed include the therapeutic properties of FQ, as well as known side effects including its contribution to FQ-induced tendon damage, results of various analysis conducted by the authors including reverse-transcriptase quantitative polymerase chain reaction analysis and the healing outcomes of those treated with FQ.

Objective To investigate whether the changes in collagen gene expression in osteoarthritic (OA) human chondrocytes are associated with changes in the DNA methylation status in the COL2A1 enhancer and COL9A1 promoter. Methods Expression levels were determined using quantitative reverse transcription-polymerase chain reaction, and the percentage of DNA methylation was quantified by pyrosequencing. The effect of CpG methylation on COL9A1 promoter activity was determined using a CpG-free vector; cotransfections with expression vectors encoding SOX9, hypoxia-inducible factor 1α (HIF-1α), and HIF-2α were carried out to analyze COL9A1 promoter activities in response to changes in the methylation status. Chromatin immunoprecipitation assays were carried out to validate SOX9 binding to the COL9A1 promoter and the influence of DNA methylation. Results Although COL2A1 messenger RNA (mRNA) levels in OA chondrocytes were 19-fold higher than those in the controls, all of the CpG sites in the COL2A1 enhancer were totally demethylated in both samples. The levels of COL9A1 mRNA in OA chondrocytes were 6,000-fold lower than those in controls; 6 CpG sites of the COL9A1 promoter were significantly hypermethylated in OA patients as compared with controls. Treatment with 5-azadeoxycitidine enhanced COL9A1 gene expression and prevented culture-induced hypermethylation. In vitro methylation decreased COL9A1 promoter activity. Mutations in the 5 CpG sites proximal to the transcription start site decreased COL9A1 promoter activity. Cotransfection with SOX9 enhanced COL9A1 promoter activity; CpG methylation attenuated SOX9 binding to the COL9A1 promoter. Conclusion This first demonstration that hypermethylation is associated with down-regulation of COL9A1 expression in OA cartilage highlights the pivotal role of epigenetics in OA, involving not only hypomethylation, but also hypermethylation, with important therapeutic implications for OA treatment. [ABSTRACT FROM AUTHOR]

Background: The non-canonical NF-κB activating kinase IKKα, encoded by CHUK (conserved-helix-loop-helix-ubiquitous-kinase), has been reported to modulate pro- or anti- inflammatory responses, cellular survival and cellular differentiation. Here, we have investigated the mechanism of action of IKKα as a novel effector of human and murine chondrocyte extracellular matrix (ECM) homeostasis and differentiation towards hypertrophy. Methodology/Principal Findings: IKKα expression was ablated in primary human osteoarthritic (OA) chondrocytes and in immature murine articular chondrocytes (iMACs) derived from IKKαf/f:CreERT2 mice by retroviral-mediated stable shRNA transduction and Cre recombinase-dependent Lox P site recombination, respectively. MMP-10 was identified as a major target of IKKα in chondrocytes by mRNA profiling, quantitative RT-PCR analysis, immunohistochemistry and immunoblotting. ECM integrity, as assessed by type II collagen (COL2) deposition and the lack of MMP-dependent COL2 degradation products, was enhanced by IKKα ablation in mice. MMP-13 and total collagenase activities were significantly reduced, while TIMP-3 (tissue inhibitor of metalloproteinase-3) protein levels were enhanced in IKKα-deficient chondrocytes. IKKα deficiency suppressed chondrocyte differentiation, as shown by the quantitative inhibition of.Alizarin red staining and the reduced expression of multiple chondrocyte differentiation effectors, including Runx2, Col10a1 and Vegfa,. Importantly, the differentiation of IKKα-deficient chondrocytes was rescued by a kinase-dead IKKα protein mutant. Conclusions/Significance: IKKα acts independent of its kinase activity to help drive chondrocyte differentiation towards a hypertrophic-like state. IKKα positively modulates ECM remodeling via multiple downstream targets (including MMP-10 and TIMP-3 at the mRNA and post-transcriptional levels, respectively) to maintain maximal MMP-13 activity, which is required for ECM remodeling leading to chondrocyte differentiation. Chondrocytes are the unique cell component in articular cartilage, which are quiescent and maintain ECM integrity during tissue homeostasis. In OA, chondrocytes reacquire the capacity to proliferate and differentiate and their activation results in pronounced cartilage degeneration. Τηυσ, our findings are also of potential relevance for defining the onset and/or progression of OA disease. [ABSTRACT FROM AUTHOR]

Objective Wnt-1-inducible signaling pathway protein 3 (WISP-3)/CCN6 is mutated in progressive pseudorheumatoid dysplasia and may have effects on cartilage homeostasis. The aim of this study was to ascertain additional roles for WISP-3/CCN6 by determining its expression in osteoarthritic (OA) cartilage and by investigating its effects on cartilage-relevant metalloproteinase expression in immortalized (C-28/I2) and primary chondrocytes. Methods Cartilage steady-state levels of WISP-3/CCN6 messenger RNA and protein production were determined by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. WISP-3/CCN6 was overexpressed in C-28/I2 cells, and the resultant clones were analyzed by quantitative RT-PCR. The stable clones were analyzed by RT-PCR for metalloproteinase expression, and the signaling pathways involved were investigated using pharmacologic inhibition. The effects of WISP-3/CCN6 on metalloproteinase expression in primary chondrocytes were investigated using a small interfering RNA approach. Results WISP-3/CCN6 was highly expressed in OA cartilage compared with undamaged cartilage, at both the RNA and protein levels. WISP-3/CCN6 overexpression in C-28/I2 cells resulted in unexpected dual regulation of metalloproteinases; expression of the potent aggrecanase ADAMTS-5 was down-regulated 9-fold, while expression of MMP-10 was up-regulated 14-fold, and these responses were accentuated in the WISP-3/CCN6 clones grown in suspension. MMP-10 up-regulation was dependent on several MAPKs, but WISP-3/CCN6-mediated ADAMTS-5 repression was independent of these pathways and was partially relieved by activation of β-catenin signaling. WISP-3/CCN6 also suppressed ADAMTS-5 expression in C-28/I2 cells treated with cytokines. In cytokine-treated primary chondrocytes, gene silencing of WISP-3/CCN6 resulted in enhanced ADAMTS-5 expression, while MMP-10 expression was suppressed. Conclusion WISP-3/CCN6 was highly expressed in end-stage OA cartilage, suggesting a role for this growth factor in cartilage homeostasis. WISP-3/CCN6-induced repression of ADAMTS-5 expression and regulation of MMP-10 expression suggest complex and context-dependent roles for WISP-3/CCN6 in cartilage biology. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Caesalpinia sappan is a common remedy in Traditional Chinese Medicine and possesses diverse biological activities including anti-inflammatory properties. Osteoarthritis (OA) is a degenerative joint disease with an inflammatory component that drives the degradation of cartilage extracellular matrix. In order to provide a scientific basis for the applicability of Caesalpinia sappan in arthritic diseases, the present study aimed to assess the effects of an ethanolic Caesalpinia sappan extract (CSE) on human chondrocytes and macrophages. Materials and methods: Primary human chondrocytes were isolated from cartilage specimens of OA patients. Primary cells, SW1353 chondrocytes and THP-1 macrophages were serum-starved and pretreated with different concentrations of CSE prior to stimulation with 10ng/ml of interleukin-1beta (IL-1β) or lipopolysaccharide (LPS). Following viability tests, nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) were evaluated by Griess assay and ELISA, respectively. Using validated real-time PCR assays, mRNA levels of IL-1β, TNF-α, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were quantified. SW1353 cells were cotransfected with a COX-2 luciferase reporter plasmid and nuclear factor-kappa-B (NF-κB) p50 and p65 expression vectors in the presence or absence of CSE. Results: CSE dose-dependently inhibited the expression of pro-inflammatory cytokines IL-1β and TNF-α in IL-1β-stimulated chondrocytes and LPS-stimulated THP-1 macrophages. CSE further suppressed the synthesis of NO in primary OA chondrocytes by blocking iNOS mRNA expression. The inhibition of COX-2 transcription was found to be related with the CSE inhibition of the p65/p50-driven transactivation of the COX-2 promoter. Conclusions: The present report is first to demonstrate the anti-inflammatory activity of CSE in an in vitro cell model of joint inflammation. CSE can effectively abrogate the IL-1β-induced over-expression of inflammatory mediators at the transcriptional level in human chondrocytes and macrophages, most likely by inhibiting NF-κB (p65/p50) signaling. Blockade of IL-1β-induced NF-κB signaling and its downstream pro-inflammatory targets by CSE may be beneficial for reducing cartilage breakdown in arthritis. [Copyright &y& Elsevier]