Preferential Association of Lissencephaly-1 Gene Expression with CD133+ Glioblastoma Cells

Abstract

Lissencephaly-1 (Lis1) protein is a dynein-binding protein involved in neural stem cell division, morphogenesis and motility. To determine whether Lis1 is a key factor in glioblastoma, we evaluated its expression and function in CD133+ glioblastoma cells. Global, Lis1 gene expression is similar in glioblastoma and normal samples. Interestingly, immunohistochemistry data indicate increased Lis1 expression colocalized with CD133 in a subset of glioma cells, including the tumor cells with perivascular localization. Lis1 gene expression is increased up to 60-fold in CD133 positive cells isolated from primary cultures of glioblastoma and U87 glioblastoma cell line as compared to CD133 negative cells. To investigate the potential role of Lis1 in CD133+ glioblastoma cells, we silenced Lis1 gene in U87 cell line obtaining shLis1-U87 cells. In shLis1-U87 cell culture we noticed a significant decrease of CD133+ cells fraction as compared with control cells and also, CD133+ cells isolated from shLis1-U87 were two times less adhesive, migratory and proliferative, as compared with control transfected U87 CD133+ cells. Moreover, Lis1 silencing decreased the proliferative capacity of irradiated U87 cells, an effect attributable to the lower percentage of CD133+ cells. This is the first report showing a preferential expression of Lis1 gene in CD133+ glioblastoma cells. Our data suggest a role of Lis1 in regulating CD133+ glioblastoma cells function.

Fighting Cancer Stem Cell Fate by Targeting LIS1 a WD40 Repeat Protein

“…Some authors report that LIS1 is down-regulated in hepatocellular carcinoma and that lis1 knock-out in mice models promotes tumorigenesis (20, 21). Our previous results show that the levels of LIS1 are low in the whole population of glioblastoma cells, the difference residing in the levels of LIS1 in glioblastoma CSC, which are upregulated (14). Therefore, the levels of LIS1 in hepatocellular carcinoma CSC should be measured since this subpopulation might be responsible for the tumor progression.…”

“…This protein, which interacts with dynein, influences the orientation of the division plane relative to the cell determinants segregation and thus it has an essential role in controlling the stem cell fate (10–12). Our recent studies demonstrate by using qRT-PCR that although no statistically significant difference exists between the mRNA expression level of LIS1 gene in glioblastoma compared with normal brain tissue, a spectacular difference (expression of up to 60-fold higher) was found between LIS1 mRNA expression in CD133+ compared to CD133- primary glioblastoma cells (13, 14). Also, previous work proved the important role of LIS1 in maintaining CD133+ cell populations in glioblastoma, as well as the involvement of LIS1 in adhesion, migration and proliferation of CD133+ U87 glioblastoma cell line.…”

“…Another study demonstrated that LIS1 plays an essential role in maintaining both normal and malignant hematopoietic stem cells (4). A more recent report has shown that LIS1 gene is preferentially expressed in CD133+ glioblastoma cells and may play an essential role in regulating CD133+ glioblastoma cells function (14). Therefore, in light of these previously published studies, we suggest that LIS1 may play a universal role in regulating the CD133+ cancer cell population in solid cancer.…”

“…Also, previous work proved the important role of LIS1 in maintaining CD133+ cell populations in glioblastoma, as well as the involvement of LIS1 in adhesion, migration and proliferation of CD133+ U87 glioblastoma cell line. Silencing LIS1 gene in U87 demonstrated a decrease of up to 6-folds of the percentage of CD133+ glioblastoma cells and a reduction of cell proliferation, migration and adhesion (13, 14). The shLIS1-U87 cells were significantly more sensitive to radiation (due to decreased radio-resistant CD133+ cell population) as compared to control U87 (14).…”

“…Silencing LIS1 gene in U87 demonstrated a decrease of up to 6-folds of the percentage of CD133+ glioblastoma cells and a reduction of cell proliferation, migration and adhesion (13, 14). The shLIS1-U87 cells were significantly more sensitive to radiation (due to decreased radio-resistant CD133+ cell population) as compared to control U87 (14). Also, recent results showed that shLIS1 U87 cells treated with temozolomide and radiotherapy have a significant lower proliferation rate than control U87 cells (15).…”