The role of Axin2+ cells in periodontal tissue development and regeneration / 口腔疾病防治

@#As a highly conserved signal pathway in evolution, the WNT signaling pathway plays an essential role in periodontium growth, development and injury repair. The Axin-associated protein Axin2 is a direct effector molecule of the WNT signaling pathway and labels WNT-responsive cells well. Studies have shown that Axin2-positive (Axin2+) cells in the periodontium have the potential for self-renewal, replication and multidirectional differentiation. This article reviews the temporal and spatial distribution of Axin2+ cells in periodontal tissue development and the role and regulatory mechanism of Axin2+ cells in periodontal tissue development, regeneration and tissue remodeling to provide new ideas for periodontal tissue regeneration. The literature review showed that Axin2+ cells were the main cell source of periodontium development, and Axin2+ cells played essential roles in tooth extraction socket healing, implant osseointegration, periodontal tissue remodeling and junctional epithelium regeneration. The function of Axin2+ cells was positively regulated by the canonical WNT signaling pathway. However, the regulatory mechanisms of other signaling pathways on Axin2+ cells remain to be elucidated.

AXIN2-associated adenomatous colorectal polyposis

Abstract: Introduction Most cases of colorectal cancer (CRC) occur sporadically; however, ~3% to 6% of all CRCs are related to inherited syndromes, such as Lynch syndrome and familial adenomatous polyposis (FAP). The adenomatous polyposis coli (APC) andmutY DNA glycosylase (MUTYH) germline mutations are the main genetic causes related to colorectal polyposis. Nevertheless, in many cases mutations in these genes have not been identified. The aim of the present case report is to describe a rare case of genetic colorectal polyposis associated with the axis inhibition protein 2 (AXIN2) gene. Case Report: The first colonoscopy screening of a 61-year-old male patient with no known family history of CRC revealed ~ 50 colorectal polyps. A histological evaluation of the resected polyps showed low-grade tubular adenomas. Germline genetic testing through a multigene panel for cancer predisposition syndromes revealed a pathogenic variant in the AXIN2 gene. In addition to colorectal polyposis, the patient had mild features of ectodermal dysplasia: hypodontia, scant body hair, and onychodystrophy. Discussion: The AXIN2 gene acts as a negative regulator of the Wnt/β -catenin signaling pathway, which participates in development processes and cellular homeostasis. Further studies are needed to support the surveillance recommendations for carriers of the AXIN2 pathogenic variant. (AU)

Garlic-derived compound -allylmercaptocysteine inhibits hepatocarcinogenesis through targeting LRP6/Wnt pathway

Whether and how garlic-derived -allylmercaptocysteine (SAMC) inhibits hepatocellular carcinoma (HCC) is largely unknown. In the current study, the role of low-density lipoprotein receptor (LDLR)-related protein 6 (LRP6) in HCC progression and the anti-HCC mechanism of SAMC was examined in clinical sample, cell model and xenograft/orthotopic mouse models. We demonstrated that SAMC inhibited cell proliferation and tumorigenesis, while induced apoptosis of human HCC cells without influencing normal hepatocytes. SAMC directly interacted with Wnt-pathway co-receptor LRP6 on the cell membrane. LRP6 was frequently over-expressed in the tumor tissue of human HCC patients (66.7% of 48 patients) and its over-expression only correlated with the over-expression of -catenin, but not with age, gender, tumor size, stage and metastasis. Deficiency or over-expression of LRP6 in hepatoma cells could partly mimic or counteract the anti-tumor properties of SAMC, respectively. administration of SAMC significantly suppressed the growth of Huh-7 xenograft/orthotopic HCC tumor without causing undesirable side effects. In addition, stable down-regulation of LRP6 in Huh-7 facilitated the anti-HCC effects of SAMC. In conclusion, LRP6 can be a potential therapeutic target of HCC. SAMC is a promising specific anti-tumor agent for treating HCC subtypes with Wnt activation at the hepatoma cell surface.

Association of single nucleotide polymorphisms in AXIN2, BMP4, and IRF6 with Non-Syndromic Cleft Lip with or without Cleft Palate in a sample of the southeast Iranian population

Abstract Non-syndromic cleft lip with or without palate (NSCL/P) is a common congenital malformation worldwide, with complex etiology. It has been proposed that interaction of genes and environmental factors play a role in the predisposition to this disease. Objectives: The aim of this study was to examine the association between AXIN2 (axis inhibition protein 2) rs7224837, BMP4 (bone morphogenetic protein 4) rs17563, and IRF6 (interferon regulatory factor 6) rs861019 and 2235371 polymorphisms and NSCL/P in an Iranian population. Material and Methods: This case-control study was carried out on 132 unrelated NSCL/P patients and 156 healthy subjects. The variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The findings suggest that BMP4 rs17563 polymorphism significantly decreased the risk of NSCL/P in codominant (OR=0.36, 95%CI=0.17-0.79, p=0.012, CT vs CC and OR=0.11, 95%CI=0.01-0.88, p = 0.019, TT vs CC), dominant (OR=0.30, 95%CI=0.15-0.62, p = 0.0007, CT+TT vs CC), recessive (OR=0.12, 95%CI=0.02-0.99, p = 0.023, TT vs CC+CT), overdominant (OR=0.39, 95%CI = 0.18-0.84, p=0.021, CT vs CC+TT), and allele (OR=0.28, 95%CI=0.15-0.55, p<0.0001, T vs C) inheritance models. Our findings did not support an association between AXIN2 rs7224837 and IRF6 rs861019 polymorphism and risk/protection of NSCL/P. The IRF6 2235371 variant was not polymorphic in our population. Conclusion: The results indicate that the BMP4 rs17563 variant is likely to confer a protective effect against the occurrence of NSCL/P in a sample of the southeast Iranian population.

The destruction complex of beta-catenin in colorectal carcinoma and colonic adenoma / O complexo destruidor de betacatenina no carcinoma colorretal e no adenoma cólico

ABSTRACT Objective To evaluate the destruction complex of beta-catenin by the expression of the proteins beta-catetenin, adenomatous polyposis coli, GSK3β, axin and ubiquitin in colorectal carcinoma and colonic adenoma. Methods Tissue samples from 64 patients with colorectal carcinoma and 53 patients with colonic adenoma were analyzed. Tissue microarray blocks and slides were prepared and subjected to immunohistochemistry with polyclonal antibodies in carcinoma, adjacent non-neoplastic mucosa, and adenoma tissues. The immunoreactivity was evaluated by the percentage of positive stained cells and by the intensity assessed through of the stained grade of proteins in the cytoplasm and nucleus of cells. In the statistical analysis, the Spearman correlation coefficient, Student’s t, χ2, Mann-Whitney, and McNemar tests, and univariate logistic regression analysis were used. Results In colorectal carcinoma, the expressions of beta-catenin and adenomatous polyposis coli proteins were significantly higher than in colonic adenomas (p<0.001 and p<0.0001, respectively). The immunoreactivity of GSK3β, axin 1 and ubiquitin proteins was significantly higher (p=0.03, p=0.039 and p=0.03, respectively) in colorectal carcinoma than in the colonic adenoma and adjacent non-neoplastic mucosa. The immunohistochemistry staining of these proteins did not show significant differences with the clinical and pathological characteristics of colorectal cancer and colonic adenoma. Conclusions These results suggest that, in adenomas, the lower expression of the beta-catenin, axin 1 and GSK3β proteins indicated that the destruction complex of beta-catenin was maintained, while in colorectal carcinoma, the increased expression of beta-catenin, GSK3β, axin 1, and ubiquitin proteins indicated that the destruction complex of beta-catenin was disrupted.

RESUMO Objetivo Avaliar o complexo de destruição da betacatenina no carcinoma colorretal e no adenoma do colo pela expressão das proteínas betacatenina, adenomatous polyposis coli, GSK3β, axina e ubiquitina. Métodos Amostras de tecidos de 64 doentes com carcinoma colorretal e de 53 pacientes com adenoma do colo foram analisadas. Blocos de tecidos foram submetidos ao estudo imuno-histoquímico com anticorpos policlonais nos tecidos do carcinoma, mucosa não neoplásica adjacente e adenoma. A imunorreatividade foi avaliada pela porcentagem de positividade de células coradas e pela intensidade do grau de coloração das proteínas no citoplasma e no núcleo das células. Na análise estatística, foram utilizados o coeficiente de correlação de Spearman, os testes t de Student, χ2, Mann-Whitney e de McNemar, e a análise de regressão logística univariada. Resultados No carcinoma colorretal, as expressões da betacatenina e da adenomatous polyposis coli foram significativamente maiores do que em adenomas do colo (p<0,001 e p<0,0001, respectivamente). A imunorreatividade das proteínas GSK3β, axina 1 e ubiquitina foi significativamente maior (p=0,03, p=0,039 e p=0,03, respectivamente) no carcinoma colorretal do que no adenoma e na mucosa não neoplásica adjacente. A coloração imuno-histoquímica dessas proteínas não apresentou diferenças significantes em relação às características clinicopatológicas do câncer colorretal e do adenoma. Conclusões Em adenomas, as menores expressões de betacatenina, axina 1 e GSK3β indicaram que o complexo de destruição da betacatenina estava conservado, enquanto que, no carcinoma colorretal, o aumento das expressões da betacatenina, GSK3β, 1 axina, e ubiquitina indicaram que o complexo de destruição de betacatenina estava alterado.

Expression and significance of Axin2 in pancreatic cancer cells / 临床肝胆病杂志

ObjectiveTo investigate the expression of Axin2 in pancreatic cancer cells, and to observe the influence of Axin2 on the proliferation, invasion, and migration of human pancreatic cancer cells (PANC-1). MethodsQuantitative real-time PCR was used to measure the expression of Axin2 in pancreatic cancer cell lines with different invasive abilities (PANC-1, Mia PaCa-2, and BxPC-3) and immortalized normal pancreatic cells (H6C7). PANC-1 cells with low expression were transfected with over-expressed Axin2 plasmid by transient transfection. MTT assay, Transwell assay, and scratch assay were used to determine the proliferation, invasion, and migration of cells transfected with over-expressed Axin2. One-way analysis of variance was used for comparison between multiple groups, and SNK-q test was used for comparison between any two groups. ResultsThe relative expression levels of Axin2 in PANC-1, BxPC-3, Mia PaCa-2, and H6C7 cells were 0.13±0.01, 0.42±0.05, 0.24±0.011, and 1.00±0.00, respectively, and PANC-1 cells had the lowest expression level of Axin2, with significant differences compared with the other cells (all P＜0.05). When PANC-1 cells were transfected with over-expressed Axin2 plasmid, the cells in the over-expression group had a significant increase in the expression level of Axin2 compared with those in the blank group and the negative control group (both P＜0.05). Compared with those in the non-transfection group and the blank group, PANC-1 cells in the over-expression group showed significant reductions in the proliferation, invasion, and migration abilities. ConclusionThe expression of Axin2 is down-regulated in pancreatic cancer cell lines and decreases with the increasing invasion ability, suggesting the role of tumor suppressor gene. High expression of Axin2 can reduce the proliferation, invasion, and migration abilities of PANC-1 cells.

Immunohistochemical study of the canonical and non-canonical Wnt signaling pathway in colorectal carcinoma and non-neoplastic mucosa / Estudo imunoistoquímico da via de sinalização canônica e não canônica da proteína Wnt em carcinoma colorretal e em mucosa não neoplásica

Colorectal cancer is linked to several signaling pathways such as Wnt pathway. Our objective is to detect and verify the integrity of protein members of Wnt signaling pathway in colorectal carcinoma and non-neoplastic colorectal tissue. Sixty-four patients with colorectal carcinoma provided samples of colorectal neoplasia and non-neoplastic tissues, which were prepared in tissue microarray blocks and subjected to immunohistochemical analysis. The primary antibodies used were Wnt-1, Wnt-2, Wnt-5a Frizzled-1, Frizzled-5 and axin. Immunoexpression of Wnt-2 protein was significantly lower in colorectal tumor tissue and axin protein immunoexpression was significantly higher in tumor tissue. There was no significant difference in the expression of Wnt-1, Wnt-5a, Frizzled-1 and Frizzled-5 proteins in both tissues. The higher expression of Wnt-2 protein in non-neoplastic colorectal tis- sue suggests the participation during the hyperproliferative stage of colorectal mucosa. The increased axin protein immunoexpression in colorectal tumor suggests a decrease in the formation of the beta-catenin destructor complex. (AU)

O câncer colorretal está ligado a várias vias de sinalização, como a via Wnt. Nosso objetivo é detectar e verificar a integridade das proteínas da via de sinalização Wnt no carcinoma colorretal e no tecido colorretal não neoplásico. Sessenta e quatro pacientes com carcinoma colorretal forneceram amostras de neoplasia e tecidos não neoplásicos, que foram colocadas em blocos de tissue microarray e submetidas à análise imuno-histoquímica. Os anticorpos primários utilizados foram Wnt-1, Wnt-2, Wnt-5a Frizzled-1, Frizzled-5 e axina. A imunoexpressão da proteína Wnt-2 foi significativamente menor no tecido tumoral e a imunoexpressão da proteína axina foi significativamente superior no tecido do tumor. Não houve diferença significativa na expressão de Wnt-1, Wnt-5a, frizzled-1 e nas proteínas Frizzled 1 e 5 em ambos os tecidos. A maior expressão de Wnt-2 da proteína no tecido colorretal não neoplásico sugere a participação desta proteína durante o estágio de hiperproliferação da mucosa colorretal. O aumento da imunoexpressão da proteína axina no tumor colorretal sugere uma diminuição na formação do complexo de destruição da proteína beta-catenina. (AU)

Expression of Axin, β-catenin and p53 and their significance in pleural fluid of lung adeno-carinoma patients / 临床与实验病理学杂志

Purpose To investigate the expression of Axin, β-catenin and p53 in the pleural fluid and to discuss their relationships and significances. Methods The expression of Axin, β-catenin and p53 was detected using immunocytochemistry in adenocarinoma cells of the pleural fluid from 40 patients with primary lung adenocarcinomas or reactive mesothelial cells of the pleural fluid from 40 pa-tients with benign lung diseases. Results Axin positive expression rate was 30% (12/40) in cases with primary lung adenocarcino-mas. The positive expression rate of β-catenin was 15% (6/40) on cell membrane and 60%(24/40) in cytoplasm. The expression rate of p53 was 57. 5% (23/40) in cases of primary lung adenocarcinomas. The expression of Axin was positively correlated with the membranous expression of β-catenin, and negatively correlated with p53 in cancer cells of the pleural fluids. The positive expression rate of Axin was 77. 5% (31/40), but the expression rate of p53 was 1. 25% (5/40). There was no expression ofβ-catenin in reac-tive mesothelial cells from benign lung diseases. Conclusions The expression of Axin is significantly reduced in adenocarcinoma cells. The expression rate ofβ-catenin in cytoplasm is higher than that in membrane of cancer cells. It has a certain value to detect the expression of Axin,β-catenin and p53 for diagnosis and differential diagnosis of lung adenocaicinomas from benign lung diseases.

The expression and methylation of AXIN2 gene in hepatocellular carcinoma / 中华消化杂志

Objective To investigate AXIN2 mRNA expression level in hepatocellular carcinoma (HCC) , and to analyze the effect of AXIN2 gene methylation status on its mRNA expression and HCC genesis and development. Methods Fifty-three surgical excised HCC specimens and paired adjacent non-cancerous specimens, seven normal liver specimens and five HCC cell lines were collected. The expression of AXIN2 at mRNA level and the methylation status of AXIN2 gene promoter were determined by quantitative PCR. Results The expression of AXIN2 mRNA was lower in HCC tissues (0.1629 + 0.0679) than that in adjacent non-cancerous tissues (0. 4155 + 0. 2330), and there was significant difference (Z= -2. 567, P = 0. 010). The methylation level of AXIN2 gene in HCC and adjacent non-cancerous tissues (39. 77% ±3. 89%, and 36. 92% ±2. 81%) was significantly higher than that in normal liver tissues (7. 38% ±2. 40% , t=-3. 663 ,P = 0. 009;t= -4. 591 ,P = 0. 007).AXIN2 gene was hypermethylated in all five HCC cell lines. There was a negative correlation between AXIN2 mRNA expression level and the degree of methylation ( r = -0. 458, P = 0. 032). The methylation level was higher in TNM Ⅲ patients of HCC than that in TNM Ⅰ and Ⅱ patients (P =0.008). Conclusion The down-regulation of AXIN2 gene mRNA expression is correlated with its hypermethylation status. The low expression of AXIN2 mRNA and the abnormal methylation of promoter may be one of the important mechanism of HCC genesis and development.

Akt is involved in the inhibition of cell proliferation by EGF

Axin is a negative regulator of the Wnt/beta-catenin pathway and is involved in the regulation of axis formation and proliferation. Involvement of Axin in the regulation of other signaling pathways is poorly understood. In this study, we investigated the involvement of Akt in growth regulation by Axin in L929 fibroblasts stimulated by EGF. Akt activity was increased by EGF treatment and Ras activation, respectively. Both the EGF- and Ras-induced Akt activations were abolished by Axin induction, as revealed by both Western blot and immunocytochemical analyses. The proliferation and Akt activation induced by EGF were decreased by Axin induction, and the effects of EGF were abolished by treatment of an Akt-specific inhibitor. Therefore, Axin inhibits EGF-induced proliferation of L929 fibroblasts by blocking Akt activation.

Expression of Axin in Peutz-Jeghers syndrome / 解放军医学杂志

Objective To study Axin expression in colorectal adenocarcinoma, colorectal adenoma, Peutz-Jeghers syndrome (PJS) polyp, and normal intestinal mucosa at mRNA and protein levels, and to explore the role of Axin in the pathogenesis of PJS. Methods The experiment samples, which were from the exsected normal mucosa, PJS polyps, adenomatous polyps and colorectal adenocarcinoma between Jan, 2001 and Mar, 2008 in Nanfang Hospital, each includes 32 sapamples. Immunohistochemistry was adopted to detect the Axin protein expression in each sample distinctively. Results transcriptase -polymerse chain reaction (RT-PCR) was used to detected and compare the Axin mRNA expression in 16 samples of each group. Results Of the tissues in each group, the positive Axin protein expression was located in the endochylema. The nomal mucosa group showed the most intensive expressive intensity, the olorectalc adenocarcinoma group was the least intensive, with significant difference in each group(P