Abstract: OBJECTIVE: To investigate the effect of Skp2 in gastric carcinoma induced by Helicobacter pylori L-form(Hp-L) infection. METHODS ：The BGC-823 cells were co-incubated with different amount of Hp-L， and the expressions of Skp2 mRNA and protein were detected by in situ hybridization (ISH) and immunohistochemistry (IHC). Forty cases each of chronic atrophic gastritis(CAG)，gastric intestinal metaplasia(GIM)， gastric epithelial dysplasia(GED) and gastric carcinoma(GCa) were collected，and 40 mild chronic superficial gastritis (CSG) were also collected as control group. Hp-L was examined in each group by Gram’s staining. The expressions of Skp2 mRNA and protein were also evaluated. RESULTS ：By inversion microscope，infected BGC-823 cells showed increased division indicating growth acceleration. Expressions of Skp2 showed that the positive cells gradually increased，became more obvious with increasing concentration of Hp-L and the duration of treatment in a concentration-and-time-dependent manner . The positive rate of mRNA and protein of Skp2 in CAG，GIM，GED and GCa of the positive Hp-L groups were higher than the negative groups，but only the GCa group was significant (P<0.05). CONCLSION：Skp2 showed an obvious increase in gastric pre-cancerous lesions and gastric carcinoma induced by Hp-L infection，which indicated it may play an important role in the development of gastric carcinoma.

Key words: Helicobacter pylori, L-form, Skp2, gastric carcinoma