Overexpression of IL-7 enhances cisplatin resistance in glioma.

Cisplatin is one of the most commonly used chemotherapeutic agents for glioma patients. In this study, array comparative genomic hybridization (aCGH) was used to identify genes associated with cisplatin resistance in a human glioma cell line. The cisplatin-resistant U251/CP2 cell line was derived by stepwise selection using cisplatin.

Glioblastoma stem cells resistant to temozolomide-induced autophagy.

Background: Recent studies have demonstrated the existence of a small fraction of cells with features of primitive neural progenitor cells and tumor-initiating function in brain tumors. These cells might represent primary therapeutic target for complete eradication of the tumors. This study aimed to determine the resistant phenotype of glioblastoma stem cells (GSCs) to temozolomide (TMZ) and to explore the possible molecular mechanisms underlying TMZ resistance.

Activities of DNA-PK and Ku86, but not Ku70, may predict sensitivity to cisplatin in human gliomas.

Objective: This study was designed to investigate the relationship between activities of DNA-dependent protein kinase (DNA-PK), its subunits Ku86/Ku70, and sensitivities to cisplatin in human glioma samples.

Methods: Thirty-six glioma samples from patients without prior treatment before neurosurgery were included in this study. The sensitivities to cisplatin as indicated by IC(50) (the inhibitory concentration leading to 50% cell death) were assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenytetrazolium (MTT) assay; activities of DNA-PK and Ku70/Ku86 were analyzed by SigmaTECT DNA-Dependent Protein Kinase Assay System and Ku70/Ku86 DNA Repair Kit, respectively.

DNA-dependent protein kinase activity and radiosensitivity of nasopharyngeal carcinoma cell lines CNE1/CNE2.

The present study investigated the relationship between DNA-dependent protein kinase (DNA-PK) and radiosensitivity of nasopharyngeal carcinoma (NPC) cell lines. The dose-survival relationship for NPC cell lines, CNE1 and CNE2, was analyzed using clonogenic formation assay, the activity of DNA-PK of the two cell lines was measured using the Signa TECT DNA-PK assay kit, and the localization and expression of Kus (a heterodimer) and DNA-PKcs protein in CNE1 and CNE2 before irradiation and 15 min, 1 h, 6 h, 12 h, 24 h after 4 Gy irradiation were analyzed by immunofluorescence, laser scanning confocal microscope (LSCM) and Western blot. The results showed that the surviving fraction of CNE1 was higher than that of CNE2 at each dose.

[Predictive value of in vitro MTT assay chemosensitivity test of cytotoxic drug activity in cervical cancer].

Background & Objective: In recent years, the neoadjuvant chemotherapy for cervical cancer has evoked more and more attention and has been used widely. But the chemosensitivity of individuals to various antitumor drugs is different. This study was to investigate the chemosensitivity of cervical cancer cells to antitumor drugs using in vitro MTT assay chemosensitivity test.

[Individualized chemotherapy based on drug sensitivity and resistance assay and MGMT protein expression for patients with malignant glioma--analysis of 42 cases].

Background & Objective: Malignant glioma cells are resistant to most chemotherapeutic agents. Nitrosourea and temozolomide (TMZ) are main agents for treating malignant glioma. Resistance of malignant glioma to these agents is frequently associated with high levels of DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT).

[Correlation of DNA-PK activity with anti-cancer drug-sensitivity in human gliomas].

Objective: To investigate the relationship between DNA-dependent protein kinase (DNA-PK) activity and anti-cancer drug sensitivity in human glioma tissues.

Methods: Human glioma specimens were primarily cultured and its sensitivity to several anti-cancer drugs were evaluated by MTT assay. Nuclear protein was extracted from the glioma sample of the same patient and its DNA-PK activity was determined by a biotinylated DNA-PK assay with p53-derived peptide as a specific substrate.