[Expression and prognosis effect of methylation-regulated SLIT3 and SPARCL1 genes in smoking-related lung adenocarcinoma].

Objective: To investigate the expression and prognosis effect of methylation-regulated SLIT3 and SPRCL1 genes in smoking-related lung adenocarcinoma. Methods: The expression levels of SLIT3 and SPARCL1 in cigarette smoke-induced malignant transformed cell (S30) and lung adenocarcinoma (LUAD) cell lines were measured by real-time fluorescence quantitative PCR (qPCR). Datasets of mRNA expression, DNA methylation and patient information data were obtained from The Cancer Genome Altas (TCGA) database. The mRNA expression levels of SLIT3 and SPARCL1 were validated in LUAD tissues. The 10-year survival curve of LUAD patients with different smoking history was plotted, and the correlation between mRNA expression level and DNA methylation level of LUAD patients was further analyzed. S30 cells were treated with 5-azacytidine (5-aza), an inhibitor of DNA methyltransferase, to analyze the methylation regulatory mechanism of SLIT3 and SPRCL1. Results: The qPCR results showed the significant down-regulation of SLIT3 and SPARCL1 in S30 cell and four LUAD cell lines (SLIT3: 0.493±0.134 and 0.041±0.014, 0.161±0.023, 0.277±0.055, 0.035±0.005; SPARCL1: 0.507±0.131 and 0.453±0.045, 0.420±0.040, 0.153±0.035, 0.430±0.050; all P<0.01). Bioinformatics analysis showed that SLIT3 and SPARCL1 were low expressed in LUAD tissue (8.12±1.58 vs 10.84±0.69 and 11.46±1.06 vs 13.57±0.67; both P<0.001) compared with adjacent peritumoral tissues, and expression levels of SLIT3 and SPARCL1 were significantly correlated with smoking history (both P<0.001). Non-smoker with high expression of SLIT3 and SPARCL1 was associated with better prognosis among LUAD patients. There was a significant negative correlation between promoter methylation and mRNA expression level of the two genes (r=-0.208, -0.574; both P<0.001). 5-aza treatment significantly up-regulated the expression levels of SLIT3 and SPARCL1 genes in S30 cells (2.137±0.281, 3.657±0.882; both P<0.01). Conclusion: SLIT3 and SPARCL1 can be regulated by DNA methylation and down-regulated in LUAD tissue, which has important prognostic significance on the smoking-induced LUAD patients.

The adhesion of putative probiotic lactobacilli to cultured epithelial cells and porcine intestinal mucus.

AIMS: To investigate the adhesion of lactobacilli and their subsequent competitive exclusion ability against pathogens. METHODS AND RESULTS: Four species of putative probiotic lactobacilli were studied for their adhesion abilities. First, the adhesion to Caco-2 cells was examined by light and electron microscopy. The four species were then labelled by [methyl-(3)H] thymidine and their adhesion to porcine intestinal mucus was determined by radioactivity. The tested lactobacilli showed best adhesion on ileal mucus compared with duodenal and jejunal mucus. Oxidative compound pre-treatment (NaIO(3) and NaIO(4)) dramatically decreased the adhesion of the lactobacilli to mucus. Pre-treating mucus with proteolytic enzymes (proteinase K and trypsin) resulted in the increase of adhesion in Lactobacillus serotype Reuteri I2021, but the results in the other species were variable. Lactobacillus serotype Fermentum I5007 showed greatest adhesion potential and exerted the best competitive exclusion against Salmonella and Escherichia. CONCLUSIONS: Adhesion ability in lactobacilli is species-specific. Lactobacilli with higher adhesion index have better competitive exclusion ability. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that there is a positive correlation between adhesion and competitive exclusion ability of lactobacilli. Additionally, the in vitro adhesion assay is a feasible way to screen unknown lactobacilli, potentially for future industrial applications.

Selection of adenoid cystic carcinoma cell clone highly metastatic to the lung: an experimental study.

Lung metastasis is very common in patients with adenoid cystic carcinoma (ACC). The purpose of the present study is to establish a model for an experimental study of ACC metastatic mechanisms and antimetastatic procedures. After five repeated selection in vivo, combined with an in vitro cloning technique and analysis of platelet aggregation activity, a clone (Acc-M) highly metastatic to the lung was selected from an ACC cell line (Acc-2). The metastatic rate was 96% vs 18% for Acc-M and the Acc-2 cell line. The metastatic rate and the weight of the lung with metastases correlated positively with platelet aggregation activity. The present study might be important for research into mechanisms of ACC metastases.

[The clinical analysis of oral squamous cell carcinoma under age of 40 years old]

44 cases of oral squamous cell carcinoma under 40 years old were analyzed retrospectively.The ratio of male to female was 1.93:1,the youngest was 3,and the majority were within 30-40 years old.The predict site was on the tongue,21 cases shown and accounting for 66.90%.Histologically,the most cases were highly differentiated,accounting for 81092%.About one half cases were present in the terminal clinical stage,and for tongue cancer,terminal stage cases were as high as 61.90%.The patients did not cooperate with treatment very well,only minority could fulfill combined therapy in strict meaning.The recurrence was high and might affected the prognosis.The results were discussed and literatures were reviewed.