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The purpose of this study was to clarify the role of human beta defensin-1 (hBD-1) in predicting PAC in morphologically normal prostate glands. In total, 25 patients with a negative initial biopsy for PAC and diagnosed as PAC positive in subsequent biopsies performed within 1 year of the initial biopsy were included. As a control group, 22 patients negative for PAC in at least three consecutive histologic examinations were selected. Expression of hBD-1 was analyzed separately via immunohistochemistry in paired cores of non-neoplastic gland and PAC in the false-negative group and control group. Loss of hBD-1 expression was observed in 95.6% and 90.0% PAC cases with Gleason Patterns 3 and 4 in repeat biopsies, respectively. hBD-1 loss of basal cells in 40 (85.1%) previous non-neoplastic biopsy cores in the false-negative group was observed, in contrast to preserved basal cell expression of hBD-1 in 64 (72.7%) biopsy cores in the control group (p = 0.001). Multivariate logistic regression analysis showed that hBD-1 basal cell loss (≥20% of prostatic glands in total cores) is an independent factor for predicting PAC (odds ratio: 4.739, confidence interval: 1.093-20.554, p = 0.038). hBD-1 loss of basal cells is a useful indicator to identify extremely high-risk patients with initially negative biopsy., (© 2017 APMIS. Published by John Wiley & Sons Ltd.)

Vaginal commensal lactobacilli are considered to contribute significantly to the control of vaginal microbiota by competing with other microflora for adherence to the vaginal epithelium and by producing antimicrobial compounds. However, the molecular mechanisms of symbiotic prokaryotic-eukaryotic communication in the vaginal ecosystem remain poorly understood. Here, we showed that both DNA methylation and histone modifications were associated with expression of the DEFB1 gene, which encodes the antimicrobial peptide human β-defensin-1, in vaginal keratinocyte VK2/E6E7 cells. We investigated whether exposure to Lactobacillus gasseri and Lactobacillus reuteri would trigger the epigenetic modulation of DEFB1 expression in VK2/E6E7 cells in a bacterial species-dependent manner. While enhanced expression of DEFB1 was observed when VK2/E6E7 cells were exposed to L. gasseri, treatment with L. reuteri resulted in reduced DEFB1 expression. Moreover, L. gasseri stimulated the recruitment of active histone marks and, in contrast, L. reuteri led to the decrease of active histone marks at the DEFB1 promoter. It was remarkable that distinct histone modifications within the same promoter region of DEFB1 were mediated by L. gasseri and L. reuteri. Therefore, our study suggested that one of the underlying mechanisms of DEFB1 expression in the vaginal ecosystem might be associated with the epigenetic crosstalk between individual Lactobacillus spp. and vaginal keratinocytes.

Epigenetic aberrations play crucial roles in prostate cancer (PCa) development and progression. The DEFB1 gene, which encodes human ß-defensin-1 (HBD-1), contributes to innate immune responses and functions as a potential tumor suppressor in urological cancers. We investigated whether differential DNA methylation at the low CpG-content promoter (LCP) of DEFB1 was associated with transcriptional regulation of DEFB1 in PCa cells. To identify distinct CpG loci within the DEFB1 LCP related to the epigenetic regulation of DEFB1, we performed an in vitro methylated reporter assay followed by bisulfite sequencing of the DEFB1 promoter fragment. The methylation status of two adjacent CpG loci in the DEFB1 LCP was found to be important for DEFB1 expression in PCa cells. Paired epithelial specimens of PCa patients (n = 60), which were distinguished as non-tumor and tumor tissues by microdissection, were analyzed by bisulfite pyrosequencing of site-specific CpG dinucleotide units in the DEFB1 LCP. CpG methylation frequencies in the DEFB1 LCP were significantly higher in malignant tissues than in adjacent benign tissues across almost all PCa patients. These results suggested that methylation status of each CpG site in the DEFB1 promoter could mediate downregulation of DEFB1 in PCa cells., Competing Interests: The authors have declared that no competing interests exist.

Previously, using the Illumina HumanHT-12 microarray we found that β-defensin 131 (DEFB131), an antimicrobial peptide, is upregulated in the human prostate epithelial cell line RWPE-1 upon stimulation with lipoteichoic acid (LTA; a gram-positive bacterial component), than that in the untreated RWPE-1 cells. In the current study, we aimed to investigate the role of DEFB131 in RWPE-1 cells during bacterial infection. We examined the intracellular signaling pathways and nuclear responses in RWPE-1 cells that contribute to DEFB131 gene induction upon stimulation with LTA. Chromatin immunoprecipitation was performed to determine whether NF-κB directly binds to the DEFB131 promoter after LTA stimulation in RWPE-1 cells. We found that DEFB131 expression was induced by LTA stimulation through TLR2 and p38MAPK/NF-κB activation, which was evident in the phosphorylation of both p38MAPK and IκBα. We also found that SB203580 and Bay11-7082, inhibitors of p38MAPK and NF-κB, respectively, suppressed LTA-induced DEFB131 expression. The chromatin immunoprecipitation assay showed that NF-κB directly binds to the DEFB131 promoter, suggesting that NF-κB is a direct regulator, and is necessary for LTA-induced DEFB131 expression in RWPE-1 cells. Interestingly, with DEFB131 overexpression in RWPE-1 cells, the accumulation of mRNA and protein secretion of cytokines (IL-1α, IL-1β, IL-6, and IL-12α) and chemokines (CCL20, CCL22, and CXCL8) were significantly enhanced. In addition, DEFB131-transfected RWPE-1 cells markedly induced chemotactic activity in THP-1 monocytes. We concluded that DEFB131 induces cytokine and chemokine upregulation through the TLR2/NF-κB signaling pathway in RWPE-1 cells during bacterial infection and promotes an innate immune response.

Objective: To investigate the expression and regulation of human β-defensin-2 (HBD-2) in the prostate., Patients and Methods: Normal human prostate epithelial cell line (RWPE-1), human prostate cancer cell lines (DU-145, PC-3), and paraffin-embedded prostate tissue from patients with benign prostatic hyperplasia (BPH) were analysed by RT-PCR and immunohistochemical staining. HBD-2 expression was also analysed by RT-PCR and ELISA in RWPE-1 cells treated with lipopolysaccharide (LPS). Nuclear factor-κB (NF-κB) activation was assessed by IκBα immunoblotting and electrophoretic mobility shift assay (EMSA)., Results: BPH tissue and all of the tested prostate cell lines other than PC-3 constitutively express HBD-2 mRNA. HBD-2 protein was strongly detected in prostate gland tissue surrounded by inflammatory cells including macrophages. Exposure to LPS induced HBD-2 upregulation and NF-κB activation, as assessed by IκBα phosphorylation and degradation in RWPE-1 cells. Bay11-7082, an NF-κB inhibitor prevented LPS-induced HBD-2 production in RWPE-1 cells., Conclusions: Prostate epithelial cells may constitutively express HBD-2, and its expression was upregulated by LPS. Our data indicate that HBD-2 may be an important immunomodulatory factor in prostate function. Expression of HBD-2 in normal prostates and the potential role of HBD-2 in prostatitis and BPH should be addressed in the future., (© 2010 THE AUTHORS. JOURNAL COMPILATION © 2010 BJU INTERNATIONAL.)

We investigated the expression of HBD-1 and -2 in vaginal epithelial cells treated with lipopolysaccharide (LPS) and the effects on HBD-2 expressions by 17beta-estradiol and progesterone. Primary vaginal epithelial cells were isolated from a segment of normal anterior vaginal wall obtained during vaginoplasty and were cultured in keratinocyte growth medium and were allowed to undergo their 3rd passage. Expression of HBD-1 and -2 by different stimuli using LPS 0.5 microg/ml, 17beta-estradiol 2 nM and progesterone 1 microM was measured by RT-PCR, ELISA and real-time RT-PCR, respectively. HBD-1 was produced constitutively in vaginal epithelial cells and the production of HBD-1 was not influenced by LPS, 17beta-estradiol and progesterone, but the production of HBD-2 was increased inducibly by LPS. 17beta-Estradiol and progesterone did not change the production of HBD-2 in normal state, but 17beta-estradiol increased the production of HBD-2 and progesterone suppressed the production of HBD-2 under the circumstances with infection. The HBD-2 plays an important role at innate host defense on genitourinary tract. The lacks of estrogen during menopause or uses of a progesterone-based oral contraceptive in sexually active women may influence production of HBD-2 in vaginal epithelium and may increase susceptibility to bacterial vaginitis or recurrent UTI., (Copyright 2009 Elsevier Ltd. All rights reserved.)