Abstract A25: Role of ABCB5 in progression and therapeutic resistance of glioblastoma

Glioblastoma multiforme (GBM), one of the most lethal human cancers, is the most common and aggressive primary malignant brain tumor. Poor prognosis and high lethality result from tumor recurrence and extreme resistance to chemotherapeutic treatment. Compelling evidence suggests that GBM is a heterogeneous tumor composed of bulk tumor cells as well as of subpopulations of slow-proliferating cancer stem cells with tumor-initiating potential, which evade cell killing and are responsible for tumor recurrence. Current therapeutic strategies are thus aimed at eliminating these refractory tumor subpopulations to alleviate chemoresistance and recurrence of GBM. ATP-binding cassette member B5 (ABCB5) has been identified as a molecular marker for distinct subsets of chemoresistant tumor-initiating cell populations in diverse human malignancies, including malignant melanoma, hepatocellular carcinoma and colorectal cancer. Moreover, ABCB5 has been shown to functionally contribute to tumor progression and therapeutic resistance of human cancers. In the current study, we examined the potential role of ABCB5 in malignant growth and chemoresistance of GBM. We found ABCB5 to be co-expressed with GBM stem cell marker CD133 in all of three human GBM cell lines tested thus far, i.e. U87 MG, LN18 and LN229. Functional blockade of ABCB5 using an anti-ABCB5 monoclonal antibody (mAb) (clone 3C2-1D12) inhibited proliferation and survival of human GBM cells, and sensitized GBM cultures to Temozolomid...
Source: Molecular Cancer Research - Category: Cancer & Oncology Authors: Tags: Pediatric Cancers and Development: Poster Presentations - Proffered Abstracts Source Type: research