Purpose: Glioma is the most common malignant brain tumor. The molecular mechanisms underlying its malignancy are not fully understood. LAMC1, which encodes extracellular matrix protein laminin γ1, has been implicated in some malignant tumors but has not been systematically evaluated in glioma. The aim of this study was to evaluate the expression of LAMC1 and its clinical significance.
Patients and methods: LAMC1 protein expression in 52 fresh-frozen specimens of different pathological grade gliomas and 5 normal brain tissues was detected by Western blotting. Immunohistochemistry was used to detect LAMC1 protein expression in another set of 76 glioma tissues and 8 normal brain tissues. The associations between clinicopathological factors and LAMC1 expression were analyzed. A log-rank test and a multivariate Cox proportional hazards model were used to determine the relationship between LAMC1 expression and patient prognosis. The expression of LAMC1 at the mRNA level was analyzed in the TCGA database.
Results: LAMC1 was highly expressed in high-grade glioma tissues, with moderate expression in low-grade gliomas, and weak or no expression in normal brain tissues, as detected by Western blotting and immunohistochemistry. A chi-square test indicated that LAMC1 expression was associated with pathological grade but not with other clinicopathological factors, such as age, sex, and tumor size. LAMC1 expression at the mRNA level was upregulated in high-grade gliomas compared with low-grade gliomas and normal brain tissue in the TCGA database. The Kaplan–Meier plot and log-rank test in our patient series showed that high LAMC1 expression was significantly associated with shorter survival, which was consistent with the TCGA database analysis. A multivariate Cox proportional hazards model revealed that LAMC1 expression, WHO grade, and surgery procedure were significantly correlated with overall survival and progression-free survival.
Conclusion: These results demonstrated that LAMC1 may play an important role in glioma progression and may be used in the diagnosis, prognosis, and targeted therapy of glioma patients.
Keywords: glioblastoma, LAMC1, laminins, basement membranes, prognosis