BACKGROUND: Transcribed ultraconserved regions (T-UCRs) are a subset of long 
noncoding RNAs. It has been reported that T-UCRs are dysregulated in cancers and 
play an important role in the development and progression of malignancies. 
uc.160 was found to be a suppressive factor of cancer development, but its role 
has not been fully elucidated.
METHODS: The uc.160 expression was examined in gastric cancer tissues and 
established cell lines by quantitative reverse transcription polymerase chain 
reaction (qRT-PCR). The biological function of gastric cancer cells with uc.160 
over-expression were investigated, and the interaction between uc.160 and 
microRNA miR-155 was examined by dual-luciferase reporter assay. PTEN levels 
were detected by Western blotting. Anti-tumor effects of uc.160 were further 
explored in tumor transplantation models.
RESULTS: uc.160 expression was significantly down-regulated in gastric cancer 
tissues and gastric cell lines as compared to adjacent normal tissues and 
immortalized gastric epithelial cell line (GES-1), respectively. Over-expression 
of uc.160 in SGC-7901 and AGS gastric cancer cells significantly suppressed 
their proliferation in vitro and in vivo. Moreover, uc.160 positively regulated 
the tumor suppressor protein PTEN. Interestingly, uc.160 was inhibited by 
microRNA miR-155 that is also a negative regulator of gastric cancer.
CONCLUSION: uc.160 is significantly down-regulated in gastric carcinomas and can 
inhibit the tumor growth both in vitro and in vivo, suggesting that uc.160 may 
be used as a diagnostic marker and therapeutic target of gastric malignancies.