Objective： LRIG1 gene is a newly found human gene that displays homologies to the Drosophila Kek-1 gene. Previous researches have shown that the LRIG1 gene almost expressed in all human tissues. However, its functions, particularly its functions in human tumors, are still unknown. The goals of the present study are to magnify the expression spectrum of the LRIG1 gene and determine their roles in the oncogenesis. Methods： A triphasic oligonucleotide probe was designed and used to detect the expression level of the LRIG1 gene in 16 astrocytomas and the corresponding tissues around the tumors by in situ hybridization. 11 primary astrocytoma cells were cultured. Among these, the expression level of the LRIG1 gene was checked by in situ hybridization and the expression of the Proliferating Cell Nuclear Antigen （PCNA） protein was detected by immunohistochemistry. Results： The expression of LRIG1 protein was detected in different degree in all the tumors and the surrounding tissues. Compared to the surrounding tissues, the expression of the tumors was lower. The decrease extends from the surrounding tissues to the tumors were correlation to the tumors＇ grades. The primary cultured cells also expressed LRIG1 to various extent and the expression of LRIG1 in the cultures was negatively correlated with the intensity of the PCNA staining. Conclusion： The LRIG1 protein may inhibit the growth of tumors of glial cells and the down-regulation of the LRIG1 gene may be involved in the development and progression of the tumor.
