Expression Patterns of Grainyhead-Like 2 and Ovo-Like 2 in Mouse Mammary Gland Development During Pregnancy, Lactation, and Weaning.

Grainyhead-like 2 (Grhl2) is a transcription factor that regulates cell adhesion genes in mammary ductal development and serves as a repressor of the epithelial-mesenchymal transition. Conversely, Ovo-like2 (Ovol2) is a target gene of Grhl2 but functions as a substitute in Grhl2-deficient mice, facilitating successful epithelial barrier formation and lumen expansion in kidney-collecting ductal epithelial cells. Our objective was to examine the expression patterns of Grhl2, Ovol2, and their associated genes during the intricate phases of mouse mammary gland development. The mRNA expression of Grhl2 and Ovol2 increased after pregnancy. We observed Grhl2 protein presence in the epithelial cell's region, coinciding with acini formation, and its signal significantly correlated with E-cadherin (Cdh1) expression. However, Ovol2 was present in the epithelial region without a correlation with Cdh1. Similarly, Zeb1, a mesenchymal transcription factor, showed Cdh1-independent expression. Subsequently, we explored the interaction between Rab25, a small G protein, and Grhl2/Ovol2. The expressions of Grhl2 and Ovol2 exhibited a strong correlation with Rab25 and claudin-4, a tight junction protein. These findings suggest that Grhl2 and Ovol2 may collaborate to regulate genes associated with cell adhesion and are crucial for maintaining epithelial integrity during the different phases of mammary gland development.

LncRNA XIST sponges microRNA-448 to promote malignant behaviors of colorectal cancer cells via regulating GRHL2.

Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are essential regulators in human cancers, while the role of lncRNA X-inactive-specific transcript (XIST) in colorectal cancer (CRC) via regulating miR-448 remains largely unknown. Herein, we aimed to elucidate the effect of the XIST/miR-448/grainyhead-like 2 (GRHL2) axis on CRC development. XIST, miR-448, and GRHL2 expression in CRC tissues from patients and in human CRC cell lines was assessed. Loss- and gain-function assays were implemented to unveil the roles of XIST, miR-448, and GRHL2 in screened CRC cells. The tumor growth in vivo was observed in nude mice. Binding relations among XIST, miR-448, and GRHL2 were evaluated. XIST and GRHL2 expressed highly whereas miR-448 expressed lowly in CRC tissues and cells. XIST or GRHL2 downregulation, or miR-448 elevation suppressed the malignant behaviors of CRC cells in vitro, and downregulated XIST or upregulated miR-448 also inhibited the tumor growth in vivo. miR-448 upregulation reversed the role of XIST elevation in CRC cells. XIST particularly bound to miR-448, and miR-448 targeted GRHL2. Knockdown of XIST upregulates miR-448 to impede malignant behaviors of CRC cells via inhibiting GRHL2. This study may provide novel biomarkers for CRC diagnosis and treatment.

GRHL2 induces liver fibrosis and intestinal mucosal barrier dysfunction in non-alcoholic fatty liver disease via microRNA-200 and the MAPK pathway.

Non-alcoholic fatty liver disease (NAFLD) serves as the most common subtype of liver diseases and cause of liver dysfunction, which is closely related to obesity and insulin resistance. In our study, we sought to investigate effect of transcription factor grainyhead-like 2 (GRHL2) on NAFLD and the relevant mechanism. NAFLD mouse model was established with a high-fat feed. Then, serum was extracted from NAFLD patients and mice, followed by ectopic expression and depletion experiments in NAFLD mice and L02 cells. Next, the correlation between GRHL2 and microRNA (miR)-200 and between miR-200 and sirtuin-1 (SIRT1) was evaluated. The observations demonstrated that miR-200 and GRHL2 were overexpressed in the serum of NAFLD patients and mice, while SIRT1 was poorly expressed. GRHL2 positively regulated miR-200 by binding to miR-200 promoter region, which negatively targeted SIRT1. The inhibition of miR-200 and GRHL2 or SIRT1 overexpression lowered HA and LN in mouse liver tissue, occludin and ZO-1 in mouse small intestine tissue, TNF-α and IL-6 in mouse serum, glucose, total cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mouse serum, and also inhibited liver fibrosis and intestinal mucosal barrier dysfunction. Meanwhile, GRHL2 induced activation of MAPK signalling pathway in NAFLD mice. Collectively, GRHL2 played a contributory role in NAFLD by exacerbating liver fibrosis and intestinal mucosal barrier dysfunction with the involvement of miR-200-dependent SIRT1 and the MAPK signalling pathway.

GRHL2 Is Required for Collecting Duct Epithelial Barrier Function and Renal Osmoregulation.

Collecting ducts make up the distal-most tubular segments of the kidney, extending from the cortex, where they connect to the nephron proper, into the medulla, where they release urine into the renal pelvis. During water deprivation, body water preservation is ensured by the selective transepithelial reabsorption of water into the hypertonic medullary interstitium mediated by collecting ducts. The collecting duct epithelium forms tight junctions composed of barrier-enforcing claudins and exhibits a higher transepithelial resistance than other segments of the renal tubule exhibit. However, the functional relevance of this strong collecting duct epithelial barrier is unresolved. Here, we report that collecting duct-specific deletion of an epithelial transcription factor, grainyhead-like 2 (GRHL2), in mice led to reduced expression of tight junction-associated barrier components, reduced collecting duct transepithelial resistance, and defective renal medullary accumulation of sodium and other osmolytes. In vitro, Grhl2-deficient collecting duct cells displayed increased paracellular flux of sodium, chloride, and urea. Consistent with these effects, Grhl2-deficient mice had diabetes insipidus, produced dilute urine, and failed to adequately concentrate their urine after water restriction, resulting in susceptibility to prerenal azotemia. These data indicate a direct functional link between collecting duct epithelial barrier characteristics, which appear to prevent leakage of interstitial osmolytes into urine, and body water homeostasis.

The basal chorionic trophoblast cell layer: An emerging coordinator of placenta development.

During gestation, fetomaternal exchange occurs in the villous tree (labyrinth) of the placenta. Development of this structure depends on tightly coordinated cellular processes of branching morphogenesis and differentiation of specialized trophoblast cells. The basal chorionic trophoblast (BCT) cell layer that localizes next to the chorioallantoic interface is of critical importance for labyrinth morphogenesis in rodents. Gcm1-positive cell clusters within this layer initiate branching morphogenesis thereby guiding allantoic fetal blood vessels towards maternal blood sinuses. Later these cells differentiate and contribute to the syncytiotrophoblast of the fetomaternal barrier. Additional cells within the BCT layer sustain continued morphogenesis, possibly through a repopulating progenitor population. Several mouse mutants highlight the importance of a structurally intact BCT epithelium, and a growing number of studies addresses its patterning and epithelial architecture. Here, we review and discuss emerging concepts in labyrinth development focussing on the biology of the BCT cell layer.

A Grainyhead-Like 2/Ovo-Like 2 Pathway Regulates Renal Epithelial Barrier Function and Lumen Expansion.

Grainyhead transcription factors control epithelial barriers, tissue morphogenesis, and differentiation, but their role in the kidney is poorly understood. Here, we report that nephric duct, ureteric bud, and collecting duct epithelia express high levels of grainyhead-like homolog 2 (Grhl2) and that nephric duct lumen expansion is defective in Grhl2-deficient mice. In collecting duct epithelial cells, Grhl2 inactivation impaired epithelial barrier formation and inhibited lumen expansion. Molecular analyses showed that GRHL2 acts as a transcriptional activator and strongly associates with histone H3 lysine 4 trimethylation. Integrating genome-wide GRHL2 binding as well as H3 lysine 4 trimethylation chromatin immunoprecipitation sequencing and gene expression data allowed us to derive a high-confidence GRHL2 target set. GRHL2 transactivated a group of genes including Ovol2, encoding the ovo-like 2 zinc finger transcription factor, as well as E-cadherin, claudin 4 (Cldn4), and the small GTPase Rab25. Ovol2 induction alone was sufficient to bypass the requirement of Grhl2 for E-cadherin, Cldn4, and Rab25 expression. Re-expression of either Ovol2 or a combination of Cldn4 and Rab25 was sufficient to rescue lumen expansion and barrier formation in Grhl2-deficient collecting duct cells. Hence, we identified a Grhl2/Ovol2 network controlling Cldn4 and Rab25 expression that facilitates lumen expansion and barrier formation in subtypes of renal epithelia.

Grainyhead-like-2, an epithelial master programmer, promotes interferon induction and suppresses breast cancer recurrence.

Type-I and -III interferons play a central role in immune rejection of pathogens and tumors, thus promoting immunogenicity and suppressing tumor recurrence. Double strand RNA is an important ligand that stimulates tumor immunity via interferon responses. Differentiation of embryonic stem cells to pluripotent epithelial cells activates the interferon response during development, raising the question of whether epithelial vs. mesenchymal gene signatures in cancer potentially regulate the interferon pathway as well. Here, using genomics and signaling approaches, we show that Grainyhead-like-2 (GRHL2), a master programmer of epithelial cell identity, promotes type-I and -III interferon responses to double-strand RNA. GRHL2 enhanced the activation of IRF3 and relA/NF-kB and the expression of IRF1; a functional GRHL2 binding site in the IFNL1 promoter was also identified. Moreover, time to recurrence in breast cancer correlated positively with GRHL2 protein expression, indicating that GRHL2 is a tumor recurrence suppressor, consistent with its enhancement of interferon responses. These observations demonstrate that epithelial cell identity supports interferon responses in the context of cancer.

Regulation of S100A10 Gene Expression.

S100A10, a member of the S100 family of Ca2+-binding proteins, is a widely distributed protein involved in many cellular and extracellular processes. The best recognized role of S100A10 is the regulation, via interaction with annexin A2, of plasminogen conversion to plasmin. Plasmin, together with other proteases, induces degradation of the extracellular matrix (ECM), which is an important step in tumor progression. Additionally, S100A10 interacts with 5-hydroxytryptamine 1B (5-HT1B) receptor, which influences neurotransmitter binding and, through that, depressive symptoms. Taking this into account, it is evident that S100A10 expression in the cell should be under strict control. In this work, we summarize available literature data concerning the physiological stimuli and transcription factors that influence S100A10 expression. We also present our original results showing for the first time regulation of S100A10 expression by grainyhead-like 2 transcription factor (GRHL2). By applying in silico analysis, we have found two highly conserved GRHL2 binding sites in the 1st intron of the gene encoding S100A10 protein. Using chromatin immunoprecipitation (ChIP) and luciferase assays, we have shown that GRHL2 directly binds to these sites and that this DNA region can affect transcription of S100A10.

Expression of Grainyhead-like 2 in the Process of Ductal Development of Mouse Mammary Gland.

Grainyhead-like 2 (Grhl2) is a transcription factor regulating cell adhesion genes. Grhl2 acts as an epithelial-mesenchymal transition suppressor, and it is a proto-oncogene involved in estrogen-stimulated breast cancer proliferation. However, its expression during ovarian hormone-dependent mammary ductal development remains obscure. We here examined Grhl2 expression in the mammary gland of normal and steroid-replaced ovariectomized mice. Grhl2 protein signals were detected in both the mammary luminal epithelial and myoepithelial nuclei. The ratio and density of Grhl2-positive nuclei increased after the onset of puberty and progressed with age, whereas Grhl2-negative epithelial cells were detected in mature ducts. Claudin 3, claudin 4, claudin 7, and E-cadherin gene expression in the mammary gland was upregulated, and their expression was highly correlated with Grhl2 gene expression. Furthermore, Grhl2 mRNA expression and ductal lumen width were significantly increased by the combined treatment of estrogen and progesterone compared with estrogen alone. These results suggest that Grhl2 expressed in the luminal epithelial and myoepithelial cells from the early phase of ductal development, controlling the expression of cell adhesion molecules to establish functional ducts.

Whole blood GRHL2 expression as a prognostic biomarker in metastatic hormone-sensitive and castration-resistant prostate cancer.

BACKGROUND: As potent systemic therapies transition earlier in the prostate cancer disease course, molecular biomarkers are needed to guide optimal treatment selection for metastatic hormone-sensitive prostate cancer (mHSPC). The value of whole blood RNA to detect candidate biomarkers in mHSPC remains largely undefined. METHODS: In this cohort study, we used a previously optimised whole blood reverse transcription polymerase chain reaction assay to assess the prognostic utility [measured by seven-month undetectable prostate-specific antigen (PSA) and time to castration-resistance (TTCR)] of eight prostate cancer-associated gene transcripts in 43 mHSPC patients. Transcripts with statistically significant associations (P<0.05) were further investigated in a metastatic castration-resistant prostate cancer (mCRPC) cohort (n=119) receiving contemporary systemic therapy, exploring associations with PSA >50% response (PSA50), progression-free survival (PFS) and overall survival (OS). Clinical outcomes were prospectively collected in a protected digital database. Kaplan-Meier estimates and multivariable Cox proportional-hazards models assessed associations between gene transcripts and clinical outcomes (mHSPC covariates: disease volume, docetaxel use and haemoglobin level; mCRPC covariates: prior exposure to chemotherapy or ARPIs, haemoglobin, performance status and presence of visceral disease). Follow-up was performed monthly during ARPI treatment, three-weekly during taxane chemotherapy, and three-monthly during androgen deprivation therapy (ADT) monotherapy. Serial PSA measurements were performed before each follow-up visit and repeat imaging was at the discretion of the investigator. RESULTS: Detection of circulating Grainyhead-like 2 (GRHL2) transcript was associated with poor outcomes in mHSPC and mCRPC patients. Detectable GRHL2 expression in mHSPC was associated with a lower rate of seven-month undetectable PSA levels (25% vs. 65%, P=0.059), and independently associated with shorter TTCR (HR 7.3, 95% CI: 1.5-36, P=0.01). In the mCRPC cohort, GRHL2 expression predicted significantly lower PSA50 response rates (46% vs. 69%, P=0.01), and was independently associated with shorter PFS (HR 3.1, 95% CI: 1.8-5.2, P<0.001) and OS (HR 2.9, 95% CI: 1.6-5.1, P<0.001). Associations were most apparent in patients receiving ARPIs. CONCLUSIONS: Detectable circulating GRHL2 was a negative prognostic biomarker in our mHSPC and mCRPC cohorts. These data support further investigation of GRHL2 as a candidate prognostic biomarker in metastatic prostate cancer, in addition to expanding efforts to better understand a putative role in therapeutic resistance to AR targeted therapies.

Grainyhead-like 2 as a double-edged sword in development and cancer.

Grainyhead-like 2 (GRHL2), one of the three homologs of Drosophila grainyhead, contributes to epithelial morphogenesis and differentiation. Dysregulation of GRHL2 has been shown to be involved in hearing loss and neural tube defects during embryogenesis. Moreover, it is well-recognized that GRHL2 suppresses epithelial-to-mesenchymal transition (EMT) that is required for migration and invasion of carcinoma, implicating, GRHL2 in carcinogenesis. Diverse mechanisms, as well as the varied roles of GRHL2 in different tumor tissues, have been elucidated. However, the functions of GRHL2 appear to be more complicated than initially thought. GRHL2, acting as either a tumor enhancer or a tumor inhibitor, depends on the type of cancer. In this review, we summarize research progress about normal physiological functions of GRHL2 including epithelial morphogenesis, neural tube closure, and hearing loss. Moreover, the mechanisms of GRHL2 in tumorigenesis, containing EMT suppression, forming a negative feedback loop with ZEB1 and miR200 family, interactions with estrogen receptor (ER)-dependent signaling pathway, regulation of telomerase reverse transcriptase and relationships with TGF-beta signaling pathway are discussed in this review in an effort to better understand the roles of GRHL2 in a variety of cancers toward the goal of GRHL2-targeted treatment in the near future.

Spotlight on the Granules (Grainyhead-Like Proteins) - From an Evolutionary Conserved Controller of Epithelial Trait to Pioneering the Chromatin Landscape.

Among the transcription factors that are conserved across phylogeny, the grainyhead family holds vital roles in driving the epithelial cell fate. In Drosophila, the function of grainyhead (grh) gene is essential during developmental processes such as epithelial differentiation, tracheal tube formation, maintenance of wing and hair polarity, and epidermal barrier wound repair. Three main mammalian orthologs of grh: Grainyhead-like 1-3 (GRHL1, GRHL2, and GRHL3) are highly conserved in terms of their gene structures and functions. GRHL proteins are essentially associated with the development and maintenance of the epithelial phenotype across diverse physiological conditions such as epidermal differentiation and craniofacial development as well as pathological functions including hearing impairment and neural tube defects. More importantly, through direct chromatin binding and induction of epigenetic alterations, GRHL factors function as potent suppressors of oncogenic cellular dedifferentiation program - epithelial-mesenchymal transition and its associated tumor-promoting phenotypes such as tumor cell migration and invasion. On the contrary, GRHL factors also induce pro-tumorigenic effects such as increased migration and anchorage-independent growth in certain tumor types. Furthermore, investigations focusing on the epithelial-specific activation of grh and GRHL factors have revealed that these factors potentially act as a pioneer factor in establishing a cell-type/cell-state specific accessible chromatin landscape that is exclusive for epithelial gene transcription. In this review, we highlight the essential roles of grh and GRHL factors during embryogenesis and pathogenesis, with a special focus on its emerging pioneering function.

Polymorphism in GRHL2 gene may contribute to noise-induced hearing loss susceptibility: a meta-analysis.

INSTRUCTION: Noise-induced hearing loss is a leading occupational disease caused by gene-environment interaction. The Grainy Like 2, GRHL2, is a candidate gene. In this regard, many studies have evaluated the association between GRHL2 and noise-induced hearing loss, although the results are ambiguous and conflicting. OBJECTIVE: The purpose of this study was to identify a precise estimation of the association between rs3735715 polymorphism in GRHL2 gene and susceptibility of noise-induced hearing loss. METHODS: A comprehensive search was performed to collect data up to July 8, 2018. Finally, 4 eligible articles were included in this meta-analysis comprising 2410 subjects. The pooled odds ratios with 95% confidence intervals were used to evaluate the strength of the association. RESULTS: Significant association was found in the overall population in the dominant model (GA/AA vs. GG, odds ratio=0.707, 95% confidence interval=0.594-0.841) and allele model (G allele vs. A allele, odds ratio=1.189, 95% confidence interval=1.062-1.333). When stratified by source of the subjects, we also found association between rs3735715 and noise-induced hearing loss risk in the dominant model (GA/AA vs. GG, odds ratio=0.634, 95% confidence interval=0.514-0.783) and allele model (G allele vs. A allele, odds ratio=1.206, 95% confidence interval=1.054-1.379). CONCLUSION: Rs3735715 polymorphism in GRHL2 gene may influence the susceptibility of noise-induced hearing loss. Additional large, well-designed and functional studies are needed to confirm this association in different populations.

GRHL2 inhibits colorectal cancer progression and metastasis via oppressing epithelial-mesenchymal transition.

Our previous study has demonstrated that knockdown of Grainyhead-like 2(GRHL2) in colorectal cancer (CRC) cells inhibited cell proliferation by targeting ZEB1. This study aimed at researching whether knockdown of GRHL2 promoted CRC progression and metastasis via inducing epithelial-mesenchymal transition (EMT). GRHL2-upregulated SW-620/GRHL2+ and GRHL2-knockdown HCT116/GRHL2-KD, HT29/GRHL2-KD cells and their control cells were generated. The morphological changes after overexpression and knockdown GRHL2 were observed. qRT-PCR, Western blotting, and Immunofluorescence were used to detect EMT markers: E-cadherin, Vimentin, p-catein, ZO-1 and ZEB1 expression. Then, sh-ZEB1 was transfected to GRHL2 knockdown cells to research the relationship between GRHL2 and ZEB1. Transwell and wound healing assays were further performed to detect the impact of GRHL2 on invasion and migration in vitro. CRC cells were injected into mice tail vein to verify the impact of GRHL2 on CRC metastasis. Morphological change of mesenchymal-epithelial transition (MET) could be observed in SW620/GRHL2+ cell. The expression of epithelial markers: E-cadherin, ß-catenin, ZO-1 were up-regulated, while mesenchymal markers: Vimentin was decreased. Meanwhile, opposite EMT morphological change could be observed in HCT116/GRHL2-KD cell, accompanied by reverse change of E-cadherin, ß-catenin, ZO-1, and Vimentin. The expression level of GRHL2 and ZEB1 was found negative in both SW620/GRHL2+ and HCT116/GRHL2-KD cells. Knockdown of ZEB1 by siRNA in HCT116/GRHL2-KD and HT29/GRHL2-KD could upregulate expression of E-cadherin and GRHL2. GRHL2 knockdown also promoted migration, invasion in vitro and CRC metastasis in mice model. In conclusion, GRHL2/ZEB1 axis inhibits CRC progression and metastasis via oppressing EMT.

Knockdown of GRHL2 inhibited proliferation and induced apoptosis of colorectal cancer by suppressing the PI3K/Akt pathway.

Grainyhead-like 2 (GRHL2) transcription factor is implicated in many types of cancers. However, the role of GRHL2 in colorectal cancer (CRC) has not been fully understood. The present study aimed to evaluate the expression and functional roles of GRHL2 in CRC. The expression of GRHL2 in normal human intestinal epithelial cells and colorectal cancer cells was measured by qRT-PCR and western blot. For knockdown of GRHL2, two small interfere RNAs (siRNAs) targeting GRHL2 or control siRNA was transfected into CRC cell lines (HCT116 and HT29). For GRHL2 overexpression, the GRHL2-overexpressing vector or empty lentiviral vector was infected into HCT116 and HT29 cells. Cell proliferation was measured by MTT assay. Cell apoptosis rate was analyzed by flow cytometry. The expression of proliferating cell nuclear antigen (PCNA), Bax, and Bcl-2 was detected by western blot. We found that GRHL2 was upregulated in CRC cells compared to normal human intestinal epithelial cells. Knockdown of GRHL2 inactivated the PI3K/Akt pathway in HCT116 and HT29 cells. Knockdown of GRHL2 inhibited cell viability, elevated the apoptosis rates, suppressed the expression of PCNA and Bcl-2, and induced the expression of Bax in HCT116 and HT29 cells, and these effects were reversed by activation of the PI3K/Akt pathway. Inhibition of PI3K/Akt pathway blocked the effects of GRHL2 overexpression on cell proliferation and apoptosis. In conclusion, GRHL2 acted as an oncoprotein through regulating cell proliferation and apoptosis in CRC cells. The PI3K/Akt pathway was closely involved in the effects of GRHL2. Therefore, GRHL2 might be a therapeutic target for the CRC treatment.

Grainyhead-like-2 confers NK-sensitivity through interactions with epigenetic modifiers.

Natural Killer (NK) cells suppress tumor initiation and metastasis. Most carcinomas are heterogeneous mixtures of epithelial, mesenchymal and hybrid tumor cells, but the relationships of these phenotypes to NK susceptibility are understood incompletely. Grainyhead-like-2 (GRHL2) is a master programmer of the epithelial phenotype, that is obligatorily down-regulated during experimentally induced Epithelial-Mesenchymal Transition (EMT). Here, we utilize GRHL2 re-expression to discover unifying molecular mechanisms that link the epithelial phenotype with NK-sensitivity. GRHL2 enhanced the expression of ICAM-1, augmenting NK-target cell synaptogenesis and NK killing of target cells. The expression of multiple interferon response genes, including ICAM1, anti-correlated with EMT. We identified two novel GRHL2-interacting proteins, the histone methyltransferases KMT2C and KMT2D. Mesenchymal-epithelial transition, NK-sensitization and ICAM-1 expression were promoted by GRHL2-KMT2C/D interactions and by GRHL2 inhibition of p300, revealing novel and potentially targetable epigenetic mechanisms connecting the epithelial phenotype with target cell susceptibility to NK killing.

Polymorphism in GRHL2 gene may contribute to noise-induced hearing loss susceptibility: a meta-analysis / Polimorfismo no gene GRHL2 pode contribuir para a suscetibilidade à perda auditivainduzida por ruído: uma metanálise

Abstract Instruction: Noise-induced hearing loss is a leading occupational disease caused by gene-environment interaction. The Grainy Like 2, GRHL2, is a candidate gene. In this regard, many studies have evaluated the association between GRHL2 and noise-induced hearing loss, although the results are ambiguous and conflicting. Objective: The purpose of this study was to identify a precise estimation of the association between rs3735715 polymorphism in GRHL2 gene and susceptibility of noise-induced hearing loss. Methods: A comprehensive search was performed to collect data up to July 8, 2018. Finally, 4 eligible articles were included in this meta-analysis comprising 2410 subjects. The pooled odds ratios with 95% confidence intervals were used to evaluate the strength of the association. Results: Significant association was found in the overall population in the dominant model (GA/AA vs. GG, odds ratio = 0.707, 95% confidence interval = 0.594-0.841) and allele model (G allele vs. A allele, odds ratio = 1.189, 95% confidence interval = 1.062-1.333). When stratified by source of the subjects, we also found association between rs3735715 and noise-induced hearing loss risk in the dominant model (GA/AA vs. GG, odds ratio = 0.634, 95% confidence interval = 0.514-0.783) and allele model (G allele vs. A allele, odds ratio = 1.206, 95% confidence interval = 1.054-1.379). Conclusion: Rs3735715 polymorphism in GRHL2 gene may influence the susceptibility of noise-induced hearing loss. Additional large, well-designed and functional studies are needed to confirm this association in different populations.

Resumo Introdução: Perda auditiva induzida por ruído é uma das principais doenças ocupacionais causadas pela interação gene-ambiente. O Grainy Like 2, ou GRHL2 é um gene que tem sido considerado como candidato. Nesse sentido, muitos estudos avaliaram a associação entre o GRHL2 e perda auditiva induzida por ruído, embora os resultados sejam ambíguos e conflitantes. Objetivo: Identificar uma estimativa precisa da associação entre o polimorfismo rs3735715 no gene GRHL2 e a suscetibilidade à perda auditiva induzida por ruído. Método: Uma pesquisa abrangente foi feita para coletar dados até 8 de julho de 2018. No fim, quatro artigos elegíveis foram incluídos nesta metanálise, abrangeram 2.410 indivíduos. As odds ratios agrupadas com intervalos de confiança de 95% foram usadas para avaliar a força da associação. Resultados: Uma associação significante foi encontrada na população geral no modelo de dominância (GA/AA vs. GG, odds ratio = 0,707, intervalo de confiança 95% = 0,594-0,841) e modelo de alelo (alelo G vs. alelo A; odds ratio = 1,189, intervalo de confiança 95% = 1,062 a 1,333). Quando estratificados pelo local de trabalho dos indivíduos, também encontramos associação entre rs3735715 e risco de perda auditiva induzida por ruído no modelo de dominância (GA/AA vs. GG, odds ratio = 0,634, intervalo de confiança 95% = 0,514 ± 0,783) e modelo de alelo (alelo G vs. alelo A; odds ratio = 1,206, intervalo de confiança 95% = 1,054- 1,379). Conclusão: O polimorfismo Rs3735715 no gene GRHL2 pode influenciar a suscetibilidade à perda auditiva induzida por ruído. Estudos adicionais, amplos, bem desenhados e funcionais são necessários para confirmar essa associação em diferentes populações.

Expression of transcription factor grainyhead-like 2 is diminished in cervical cancer.

The transcription factor grainyhead-like 2 (GRHL2) is evolutionarily conserved in many different species, and is involved in morphogenesis, epithelial differentiation, and the control of the epithelial-mesenchymal transition. It has also recently been implicated in carcinogenesis, but its role in this remains controversial. Expression of GRHL2 has not previously been reported in cervical cancer, so the present study aimed to characterize GRHL2 expression in cervical cancer-derived cell lines (CCCLs) and cervical tissues with different grades of lesions. Microarray analysis found that the expression of 58 genes was down-regulated in CCCLs compared to HaCaT cells (non-tumorigenic human epithelial cell line). The expression of eight of these genes was validated by quantitative real-time PCR (qPCR), and GRHL2 was found to be the most down-regulated. Western blot assays corroborated that GRHL2 protein levels were strongly down-regulated in CCCLs. Cervical cells from women without cervical lesions were shown to express GRHL2, while immunohistochemistry found that positivity to GRHL2 decreased in cervical cancer tissues. In conclusion, a loss or strong reduction in GRHL2 expression appears to be a characteristic of cervical cancer, suggesting that GRHL2 down-regulation is a necessary step during cervical carcinogenesis. However, further studies are needed to delineate the role of GRHL2 in cervical cancer and during malignant progression.