Association of Single Nucleotide Polymorphisms in the MD-2 Gene Promoter Region With Der p 2 Allergy

Purpose

Sensitization to house dust mite (Dermatophagoides pteronyssinus) is a considerable risk factor for the progression of allergic disease. The group 2 allergen from Dermatophagoides pteronyssinus, Der p 2, is considered a major one in patients with specific immunoglobulin E (IgE) to Der p 2. Der p 2 has structural homology with myeloid differentiation 2 (MD-2), which is involved in the lipopolysaccharide-binding component of the Toll-like receptor 4 signaling pathway and the development of inflammation. The aim of this study was to examine the genetic association of single nucleotide polymorphisms (SNPs) in the promoter region of MD-2 with Der p 2-sensitive allergy.

Methods

We investigated associations between cohort''s characteristics, including 280 allergic and 80 healthy subjects by examining total IgE, eosinophils, D. pteronyssinus-specific IgE, Der p 2-specific IgE, the number of IgE-producing B cells induced by Der p 2, and the odds ratio of allergic symptoms.

Results

Based on the 1,000 genome project data, the minor allele frequencies of the rs1809441 and rs1809442 are 0.467 and 0.474, respectively. However, the correlation of linkage disequilibrium (LD) between these 2 SNPs is D''=1, the genotype frequencies of the 2 MD-2 (LY96) SNPs (rs1809441 and rs1809442) that are located nearby were significantly different between allergic and health subjects: the TT genotype of rs1809441 and the GG genotype of rs1809442 were more frequent in allergic subjects than in healthy subjects (16.1% vs 2.5% in both genotypes). The allergic patients with these genotypes exhibited significantly higher levels of D. pteronyssinus-specific IgE and Der p 2-specific Ig E, and a larger number of Der p 2-activated B cells. In addition, these 2 SNPs in the MD-2 promoter region were significantly associated with the prevalence of nasal, skin, and asthmatic allergic symptoms.

Conclusions

Our results indicated that 2 SNPs in the MD-2 promoter region were significantly associated with Der p 2-specific Ig E, and thereby suggest that these SNPs may play a major role in susceptibility to Der p 2-triggered immune responses in a Taiwanese population.     

Aberrant LRP16 protein expression in primary neuroendocrine lung tumors

Background: The Leukemia related protein 16 gene (LRP16) localized on chromosome 11q12.1, is an important estrogen-responsive gene and a crucial regulator for NF-kB activation. LRP16 is frequently expressed in human cancers; however, the LRP16 gene remains unexplored in lung neuroendocrine tumors. The aim of this study was to investigate the role of LRP16 expression in primary lung neuroendocrine tumors. Methods: lung neuroendocrine tumors were analyzed for LRP16 gene expression by two-step non-biotin immunohistochemical method. Results: Fifty of ninety (55.6%) cases of neuroendocrine lung tumors tested were positive for LRP16 protein by immunohistochemistry. The expression of LRP16 was mainly located in cytoplasm and nucleus of tumor cells. LRP16 protein was corresponding to tumor type and clinical stage, as well as survival time. Conclusions: The results indicate that abnormal LRP16 expression is noted in neuroendocrine lung tumors and the expression can give insight into the pathogenesis of the disease. The LRP16 protein may serve as a potential marker in predicting prognosis of neuroendocrine lung tumors.     

Immunohistochemistry of p53 and Ki-67 and p53 mutation analysis in renal epithelioid angiomyolipoma

Backgound: Renal epithelioid angiomyolipoma (EAML) is a rare variant of AML (angiomyolipoma) and is often associated with aggressive behaviors. The pathogenesis of EAML has been poorly understood. We analyzed the expression of p53 and Ki-67 by immunohistochemistry (IHC) and investigated p53 mutation analysis in 11 cases of EAML in comparison to classical AML. Methods: P53 and Ki-67 expression status were determined by IHC staining. P53 mutation analysis was performed using bi-directional sequencing. Results: Renal EAML tumors were significantly associated with more severe to moderate nuclear atypia (100% vs. 36.4%, P = 0.004) and mitotic activity (90.9% vs. 27.3%, P = 0.008) compared with AML tumors. Out of 11 cases of EAML, 8 were positive for p53. There was only 1 case with positive p53 expression in AML cases and expression of p53 protein showed significant difference between EAML and AML tumors (72.7% vs. 9.1%, P = 0.008). In addition, there were 7 AML and 6 EAML cases harbored P72R mutation (SNP) in exon 4 of p53. Compared with AML cases, 2 out of 11 cases of EMAL showed more than 10% positivity for ki-67. The finding of stronger p53 expression in renal EAML might have contributed to their malignant behavior. However, the abnormal p53 expression cannot be entirely explained by p53 mutations in the exons examined. Conclusions: Thus, the combination of immunohistochemical assessment of tumor antigens might improve our ability to predict the malignant outcome in EAML.     

Beclin 1 and p62 expression in non-small cell lung cancer: relation with malignant behaviors and clinical outcome

Autophagy plays a complicated role in tumorigenesis in a variety of cancers. Recently, many studies report that some autophagy-related markers could be detected in several types of human tumors. However, fewer studies have been conducted to evaluate the relationship between autophagy and lung cancer, especially in non-small cell lung cancer (NSCLC). In this study, the expression levels of autophagy-related markers Beclin 1 and p62 were detected by Western blot analysis and cell immunofluorescence staining in three human NSCLC cell lines A549, H1299 and HCC827. Then, tissue microarray and immunohistochemical staining were used to determine Beclin 1 and p62 expression in 104 NSCLC specimens collected from patients. Beclin 1 and p62 were observed to primarily distribute in the cytoplasm of the cells. Beclin 1 was expressed more predominantly in male and heavy-smoker and its expression was significantly correlated with the differentiation and lymph node metastasis. p62 expression was negatively correlated with TNM stage and lymph node metastasis. Univariate Cox regression analysis revealed that low expression of Beclin 1 and high expression of p62 were significantly associated with shorter survival. Meanwhile, multivariate Cox regression analysis indicated that Beclin 1 and p62 were independent risk factors related to overall survival for patients with NSCLC. Collectively, our study suggests that Beclin 1 and p62 could serve as potential indicators for the prognosis of patients with NSCLC.     

miR-34c-3p inhibits cell proliferation,migration and invasion of hepatocellular carcinoma by targeting MARCKS

Recent studies have shown that microRNA-34c-3p (miR-34c-3p) is down-regulated in various types of cancers and involved in tumor growth, invasion and metastasis. However, the roles of miR-34c-3p in hepatocellular carcinoma (HCC) are poorly understood. In this study, the expression profile of miR-34c-3pin HCC tissues and cell lines were examined by quantitative real-time polymerase chain reaction (qRT-PCR). The correlations of miR-34c-3p expression and clinicopathological characteristics were analyzed. The biological role of MiR-34c-3pin cell proliferation, migration and invasion was examined. In addition, the targets of miR-34c-3p were identified. The results showed that miR-34c-3p expression was significantly down-regulated in HCC tissues and cell lines; low expression level of miR-34c-3p was correlated with vascular invasion and advanced TNM stage. In vitro functional assays showed that overexpression of miR-34c-3pin HepG2 and Huh7 cells significantly reduced cell proliferation, migration and invasion. Furthermore, target analysis and luciferase assay identified myristoylated alanine-rich protein kinase c substrate (MARCKS) as a specific target of miR-34c-3p. Knockdown of MARCKS in HepG2 cells reduced cell migration and invasion, but not cell proliferation. Taken together, our findings implicate the potential application of miR-34c-3p as a tumor suppressor in cancer therapy.     

Expression of p27 and PTEN and clinical characteristics in early laryngeal squamous cell carcinoma and their correlation with recurrence

Laryngeal squamous cell carcinoma is a common malignant tumor of otolaryngeal region. At present, effective treatment of laryngeal squamous cell carcinoma still depends on surgery and radiotherapy. In recent years, application of CO₂ laser resection in the treatment of stage T1 glottic carcinoma can remove the tumor completely and reduce the injury of laryngeal tissues. But recurrence still happened in some postoperative patients. Here, we selected 131 patients to compare the therapeutic effects of CO₂ laser resection and traditional split laryngeal surgery on the early laryngeal cancer, examined the expression of p27 and PTEN by immunohistochemistry in early laryngeal squamous cell carcinoma tissues in correlation to clinical outcome. After two years follow-up 14/85 (16.5%) of CO₂ laser treatment group presented with local recurrence (recurrent group), while that of split laryngeal surgery group was 6/46 (13.0%). There was no statistical significance in recurrence rate between the two groups (P > 0.05). 10 of all the 111 (9.0%) non-recurrent patients did not follow the doctor’s advice to quit smoking after the operation, while 12 in the 20 (60.0%) recurrent patients did not; the difference between the two groups was statistically significant (P < 0.01). The positive rates of p27 were 80.2% (105/131) and 43.5% (57/131), and that of PTEN were 83.2% (109/131) and 48.9% (64/131) in the cancer adjacent tissues (negative surgical margin tissues) and in laryngeal carcinoma tissues, respectively (P < 0.001). The expression rates of p27 and PTEN in laryngeal carcinoma tissues of the recurrent group were 20.0% (4/20), 10.0% (2/20) and that in non recurrent group were 47.7% (53/111) and 55.9% (62/111), respectively, with a significant difference (P < 0.001). In addition, the expression of p27 and PTEN in tumor resected marginal tissues of the recurrence group was 50.0% (10/20), 40.0% (8/20) and that in non recurrence group was 85.6% (95/111) and 91.0% (101/111), respectively; the difference was also statistically significant between both groups (P < 0.001). In conclusion, there is no statistically significant difference in tumor recurrence rate between CO₂ laser surgery and traditional split laryngeal surgery. Postoperative recurrence is closely related to resume smoking. The recurrence rate of p27 and/or PTEN-negative patients was higher than that of the positive ones,that should be followed up closely after treatment.