Decreased expression of SPRR3 in Chinese human oesophageal cancer.

cDNA fragments that were differentially expressed between human oesophageal carcinomas and matched normal adjacent mucosa were isolated using an improved mRNA differential display technique. One of them was identified as the 3'-untranslated region of SPRR3 and was homologous to the esophagin cDNA. Northern blot, dot blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that SPRR3 expression was lost in three cell lines of oesophageal carcinoma and was dramatically decreased in 54 out of 57 primary oesophageal carcinomas compared with adjacent normal mucosa. Esophagin has been shown to be down-regulated in western oesophageal carcinomas. The data suggest that esophagin is probably the protein product of the gene SPRR3 and that altered mRNA expression of SPRR3/esophagin is a frequent event in the development of Chinese oesophageal cancer.