Combination therapy of 2-5A antisense against telomerase RNA and cisplatin for malignant gliomas

Area of Science:

• Oncology
• Molecular Biology
• Cancer Therapeutics

Background:

• Telomerase plays a crucial role in maintaining chromosome integrity in cancer cells.
• Malignant gliomas often exhibit telomerase activity, making them a target for novel therapies.
• 2',5'-Oligoadenylate (2-5A) linked to an antisense oligonucleotide against human telomerase RNA (2-5A-anti-hTR) is a newly developed therapeutic modality.

Purpose of the Study:

• To investigate the efficacy of 2-5A-anti-hTR in combination with cisplatin for treating malignant glioma.
• To evaluate the synergistic or additive effects of combined 2-5A-anti-hTR and cisplatin therapy.
• To assess the impact of combination therapy on apoptosis and tumor growth in vivo.

Main Methods:

• Six human malignant glioma cell lines with telomerase activity were treated with 0.5 microM 2-5A-anti-hTR and varying concentrations of cisplatin (0-20 microg/ml) for three days.
• Cell viability was measured using the MTT colorimetric assay.
• Apoptosis was assessed using TUNEL staining, and tumor growth was evaluated in subcutaneous xenografts in nude mice.

Main Results:

• The combination therapy demonstrated a synergistic effect at 1 microg/ml cisplatin and an additive effect at 5 microg/ml cisplatin.
• Significantly increased apoptotic cells were observed after combination therapy.
• Tumor growth in xenograft models was effectively reduced by the combination treatment.

Conclusions:

• The combination of 2-5A-anti-hTR and cisplatin exhibits synergistic anti-cancer effects against malignant glioma.
• The tumor-killing effects are, at least in part, mediated by the induction of apoptosis.
• 2-5A-anti-hTR represents a promising therapeutic agent, both as a standalone treatment and in combination with cisplatin for malignant glioma.