Relationship between let-7a and gastric mucosa cancerization and its significance.
OBJECTIVE
To investigate let-7a expression and analyze the correlation between let-7a and progression of gastric mucosa cancerization.


METHODS
The tissue microarray was constructed previously in 52 cases of human gastric carcinoma, 17 cases of chronic atrophic gastritis (atypical hyperplasia) and 11 cases of normal gastric tissue, and tissue microarrays combined with in situ hybridization were used to detect the expression of let-7a.


RESULTS
The positive rates of let-7a in normal gastric tissue, chronic atrophic gastritis and gastric carcinoma were 90.9%, 88.2% and 86.5%, respectively, without significant differences among the groups (P > 0.05). However, an intense signal of let-7a was observed in gastric epithelial cells, whereas a less intense signal was found in gastric atypical hyperplasia epithelial cells and a weak signal in gastric carcinoma epithelial cells. The expression of let-7a decreased along with the progression of gastric mucosa cancerization (P < 0.05). In the group of gastric carcinoma, the expression of let-7a was even significantly lower in gastric carcinomas with lymph node metastasis than in those without metastasis (P < 0.05).


CONCLUSIONS
Gastric carcinoma has relatively lower expression of let-7a. Reduced let-7a may be a fundamental factor in the formation and lymph node metastasis of gastric carcinoma.
Zhu
Yi-Min
YM
Department of General Surgery, The Second Hospital of Jiaxing, Jiaxing 314000, Zhejiang Province, China.
Zhong
Zheng-Xiang
ZX
Liu
Zhi-Ming
ZM
D016022:Case-Control Studies; D005753:Gastric Mucosa / Q000378:metabolism; D005757:Gastritis, Atrophic / Q000235:genetics / Q000378:metabolism; D006801:Humans; D017403:In Situ Hybridization; D008207:Lymphatic Metastasis / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism*; D012334:RNA, Neoplasm / Q000235:genetics* / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism*; D046888:Tissue Array Analysis
D035683:MicroRNAs; D012334:RNA, Neoplasm; C487931:mirnlet7 microRNA, human