Expression of LRRC4 has the potential to decrease the growth rate and tumorigenesis of glioblastoma cell line U251.

Abstract

BACKGROUND & OBJECTIVE: LRRC4 is a novel gene that the author has identified recently, which displayed significant downregulation in primary brain tumor biopsies. This study was designed to investigate if LRRC4 has the potential of suppressing brain tumor growth. METHODS: The full-length coding region of LRRC4 gene was subcloned into the expression vector pcDNA3.1, the recombinant was introduced into the glioblastoma cell line U251 by liposome transfection, and the U251 cells stably expressing LRRC4 gene were established by G418 selection. Furthermore, cell proliferation assay, soft agar assay, tumorigenesis assay were taken to examine the effect of LRRC4 expression on cell growth and tumor formation. RESULTS: U251 cells stably expressing full-length coding region of LRRC4 were established by lipofection-mediated transfection and selected for further study. Compared with the nontransfected and vector-transfected cells, the cells transfected with LRRC4 cDNA exhibited a significant increase of expression of LRRC4 mRNA by Northern blot analysis. Further, when cell proliferation was followed over several days, the cells expressing the transfected LRRC4 cDNA grew more slowly than nontransfected cells. Consistently, the cells transfected with LRRC4 exhibited markedly lower colony formation rate. These clones were injected into athymic nude mice who was killed after 40 days and the tumor sizes were evaluated. Tumor volume in mice was significantly smaller in the group of cells stably transfected with LRRC4 cDNA than in the control. CONCLUSION: LRRC4 gene may be transfected into the human glioblastoma cell line U251. The expression of LRRC4 in U251 cells may have the potential to suppress tumor cell growth and the tumorigenesis of U251 cell transplanted in nude mice.