Current Molecular Medicine - Volume 18, Issue 2, 2018

Background and Objective: Multiple signaling pathways coordinately promote epithelial-mesenchymal transition (EMT) in lens epithelial cells (LECs), where transforming growth factor beta (TGFβ)-mediated signaling plays a central role. But the mechanism of crosstalk among these pathways remains obscure. The objective of this study is to investigate the regulatory effect of the high mobility group protein A2 (HMGA2) on the signaling pathways in lens fibrosis. Methods: The human anterior capsulorhexis specimens were collected. The human SRA01/04 LEC line was cultured and treated with recombinant human TGFβ2 (5ng/ml). For inhibition of signaling pathways, a selective inhibitor SB431542, U0126 or DAPT was added to LECs respectively. The specific small interfering RNA (siRNA) were transfected to LECs for gene silence. The mRNAs expressions were measured by realtime PCR and the proteins expressions were determined by western blot and immunofluorescent staining. Results: HMGA2 and EMT markers α-smooth muscle actin (SMA), fibronectin (FN) and collagen type I (Col I) were overexpressed in human ASC specimens and TGFβ2 stimulated EMT in LECs. While blockage of EMT by a selective inhibitor of TGFβ/Smad, TGFβ/extracellular signal-regulated kinase (ERK) or Notch signaling pathway could significantly inhibited HMGA2 protein expression. And silence of HMGA2 by siRNA could significantly inhibit TGFβ2 induced expression of EMT markers including FN, Col I, collagen type IV (Col IV), key transcription factors Snail and Slug, and remarkably upregulate the epithelial markers E-cadherin and tight junction protein (ZO-1). In addition, silence of HMGA2 gene could abrogate TGFβ2 induced phosphorylation of Smad2, Smad3 as well as ERK1/2. Blockage of HMGA2 could also inhibit the upregulation of Jagged1, Notch2, and Notch3 induced by TGFβ2. Conclusion: This study indicated that HMGA2 functions as a shared effector in TGFβ2- induced lens fibrosis, modulating the signaling network necessary for EMT in a positive feedback loop.

Purpose: Thyroid-associated Ophthalmopathy (TAO) is one of the most common orbital immunological diseases in adults. CD4+ helper T (Th) cells play important roles in the pathogenesis of TAO. But the mechanisms regulating CD4+ T cell activity is unclear. This study examines T cell immunoglobulin domain and mucin domain 3 (TIM-3) expression in helper T cell type 1 (Th1), Th17, and regulatory T cells in sufferers of TAO. Methods: Participants were divided into 3 groups: patients with TAO, patients with Graves' disease but without orbitopathy (GD), and healthy control patients (HC). Peripheral blood samples were collected for each patient in the designated group. Flow cytometry methods assessed the frequency of Th1 (CD4+IFN-γ+), Th17 (CD4+IL-17+), regulatory T cells (CD4+CD25hiCD127lo), and TIM-3 protein expression. Mean fluorescence intensity (MFI) measured the magnitude of TIM-3 expression and the percentage of TIM-3+ cells for each patient. Results: Compared to the GD group, TAO patients possessed higher frequencies of Th1 and Th17 cells in peripheral blood samples. The percentage of TIM-3+ Th1 and Th17 cells was significantly lower in the TAO patients than the GD group. Across all patients sampled, TIM-3+ cell percentage negatively correlated with Th1 cell frequency. Th1 and Th17 cells exhibited significantly decreased expression of TIM-3 in TAO patients compared to healthy controls. Regulatory T cells showed little TIM-3 expression and we observed no significant differences in frequency between groups. Conclusion: These results suggest a role for TIM-3 in the regulation of Th1 and Th17 cells and the pathogenesis of Graves' ophthalmopathy.

Background: Leptin and insulin resistance have been pointed out to play a role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Increasing genes were shown to be associated with the risk of NAFLD. Objective: The study aimed to investigate the genetic association between two leptin receptor (LEPR) polymorphisms (Q223R and K109R) and the NAFLD risk. Methods: Studies were retrieved and included by using PubMed, Web of Science, the Cochrane Library databases, Chinese National Knowledge Infrastructure (CNKI) and EMBASE database. Genetic associations were assessed with pooled odds ratios (ORs) with 95% confidence intervals (CIs). Results: Five case-control studies with 1711 NAFLD patients and 1732 healthy controls were included in this meta-analysis. The K109R was significantly associated with NAFLD in allelic model in Southeast Asian subgroup (p=0.01, OR=0.59, 95% CI [0.39- 0.90]), but not in Chinese subgroup (p=0.24, OR=1.10, 95% CI [0.94-1.29]). The Q223R was significantly associated with NAFLD in both allelic and recessive models (allelic model: p<0.001, OR=0.57, 95% CI [0.50-0.65]; recessive model: p=0.001, OR=0.67, 95% CI [0.52-0.85]). However, subgroup analysis showed that the significant association between Q223R and NAFLD in allelic model cannot be found in Southeast Asians subgroup (p=0.07, OR=0.67, 95% CI [0.52-0.85]). Conclusion: LEPR K109R might be a susceptible factor for NAFLD in Southeast Asian population. And LEPR Q223R might be a susceptible factor for NAFLD in Chinese population.

Background: Our previous study demonstrated that Myosin Phosphatase Targeting subunit 1 (MYPT1) may function as a direct target of microRNA-30d, which promotes tumor angiogenesis and tumor growth of prostate cancer (PCa). Here, we aimed to investigate the clinical significance of MYPT1 expression and its functions in PCa. Methods: Roles of MYPT1 deregulation in tumor angiogenesis of PCa was determined in vitro and in vivo experiments. Expression patterns of MYPT1 and CD31 proteins were examined by immunohistochemistry and immunofluorescence, respectively. Associations of MYPT1/CD31 combination with various clinicopathological features and patients' prognosis of PCa were also statistically evaluated. Results: Through gain- and loss-of-function experiments, MYPT1 inhibited capillary tube formation of endothelial cells and in vivo tumor angiogenesis in a mouse model with the downregulation of VEGF and CD31 expression. In addition, MYPT1 expression was significantly decreased, while CD31 expression was dramatically increased in PCa tissues compared to benign prostate tissues. Notably, MYPT1 expression levels in PCa tissues were negatively correlated with that of CD31. Statistically, MYPT1-low/CD31- high expression was distinctly associated with high Gleason score, positive biochemical recurrence, and reduced overall survival of PCa patients. Moreover, PCa patients with MYPT1-low/CD31-high expression more frequently had shorter overall, biochemical recurrence-free and metastasis-free survivals. MYPT1/CD31 combination was identified as an independent factor to predict biochemical recurrence-free and metastasis-free survivals of PCa patients. Conclusions: Our findings indicate that MYPT1 may inhibit angiogenesis and contribute favorable prognosis in PCa patients, implying that MYPT1 might be a potential drug candidate in anticancer therapy.

Background: Previously, we showed that the Zinc finger-containing transcription factor ZNF424 inhibits p21 transcription, which has been widely associated with various cancers. However, because the roles of ZNF424 in tumorigenesis have not been characterized, we correlated ZNF424 expression with tumorigenesis in lung cancer. Results: The present immunohistochemical analyses show significantly lower ZNF424 expression levels in 43 of 60 lung cancer tissues compared with adjacent tissues. Moreover, flow cytometry assays indicated that overexpression of ZNF424 induces apoptosis in A549 human lung carcinoma cells, and overexpression of ZNF424 significantly increases numbers of G1 phase cells and decreases numbers of S phase cells, suggesting that ZNF424 inhibits proliferation. Western Blot analyses show that overexpression of ZNF424 decreases protein expression levels of the mitogen-activated protein kinase (MAPK) signaling proteins P-P38 and P-ERK in A549 cells. Conclusion: These are the first data to associate ZNF424 with tumorigenesis and demonstrate an inhibitory role in lung cancer, indicating the potential of ZNF424 expression as a diagnostic marker of lung tumorigenesis.

Visfatin is one of the prominent adipokines secreted by adipose tissue. The level of visfatin increases significantly in persons with obesity owing to increased body mass index (BMI). During obesity, the adipocytes, which populate adipose tissue, undergo hypertrophy and hyperplasia and secrete a number of adipocytokines including visfatin. Visfatin, which also acts as an enzyme nicotinamide phosphoribosyl transferase, is one of the prominent adipokines that influence metabolic homeostasis in the body. Visfatin exists in two forms, extracellular and intracellular, and enacts a multitude of actions. The direct and indirect evidence gathered from in-vitro, in-vivo and clinical studies indicate that visfatin modulates obesity and metabolic syndrome-related pathophysiological activities including enhanced inflammation, angiogenesis, synthesis of NAD mononucleotide, and upregulation of antiapoptotic proteins in a number of cell types. It has been implicated in a number of obesity-related alterations and metabolic derangement such as diabetes, cardiovascular complications and some forms of cancers. In this review, the novel hypothesis about the role of visfatin in diabesity has been proposed which implies recent advances in studies about the pathophysiological roles of visfatin during obesity and chronic high glucose in the circulation. Visfatin at high concentration attracts immune cells and produces chronic inflammation in adipocytes. Additionally, it induces insulin resistance in many tissues and causes pancreatic beta cells dysfunction at later stages. Further, its potential as an important target to develop molecular medicine in diabesity and related metabolic syndrome has been highlighted.

In order to combat the vast array of infectious agents it may encounter, the adaptive immune system develops a tremendously diversified antibody repertoire. B cells expressing polyreactive or autoreactive antibodies are eliminated through multiple checkpoints during early B cell development. Defects in any of these checkpoints may lead to the production of polyreactive or autoreactive antibodies, and cause autoimmune diseases. However, recent studies on a panel of established HIV-1-neutralizing antibodies and a large collection of recombinant anti-gp160 antibodies derived from HIV- 1-infected individuals showed that many of these antibodies are polyreactive or autoreactive. Whether these antibodies play important roles in combating HIV-1 infection or if they are merely by-products of chronic HIV-1 infection remains to be determined. In this review, we discuss the abnormalities in adaptive immune responses against HIV-1 infection with a focus on neutralizing antibodies against different antigenic epitopes of HIV-1 proteins. We also provide insight into the functional attributes of polyreactivity and autoreactivity as common and conserved features of HIV-1-specific antibodies. Furthermore, we summarize the autoantibodies isolated from HIV-infected individuals and their associations with clinical autoimmune diseases. Finally, we consider the opportunities and drawbacks of utilizing polyreactive antibodies from HIV-infected individuals to guide strategies aimed at developing effective antibody-based vaccine and therapeutic interventions for HIV. Understanding how polyreactive and autoreactive anti- HIV-1 antibodies are generated during the course of HIV-1 infection may provide new insights that will inform future vaccine design.