Combination treatment of TRAIL, DFMO and radiation for malignant glioma cells.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has shown potent and cancer-selective killing activity and drawn considerable attention as a promising therapy for cancer. Another promising cancer therapy is difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, which is oraly administered and well tolerated. Nevertheless, many types of cancer, including gliomas, have exhibited resistance to TRAIL-induced apoptosis and similarly the potency of DFMO should be enhanced to optimize therapeutic efficacy. In this study we sought to determine whether DFMO, in combination with TRAIL and radiation, could result in an enhanced anti-glioma effect in vitro. We investigated the effect of DFMO, TRAIL and radiation in various combinations on a panel of glioblastoma cell lines (A172, T98G, D54, U251MG). Viability and proliferation of the cells were examined with trypan blue exclusion assay, crystal violet and xCELLigence system. Apoptosis (Annexin-PI), cell cycle and activation of caspase-8 were tested with flow cytometry. BAD protein levels were determined by Western blot analysis. DFMO induced BAD overexpression. Combination treatment with DFMO, TRAIL and radiation significantly reduced cell viability in all cell lines tested. Increased induction of cell death and cell cycle arrest was confirmed with flow cytometry in A172 and D54 cell lines, while enhanced activation of annexin and caspase-8 was revealed in U251MG and T98G cells. The treatment of glioblastoma cell lines with combination of DFMO, TRAIL and radiation showed an enhanced effect. This combination treatment may represent a novel strategy for targeting glioblastoma.

3D conformal radiotherapy in primary nasopharyngeal cancer: effectiveness and prognostic factors.

PURPOSE: To assess the efficacy and safety of using 3D conformal radiation therapy (3DCRT) to treat nasopharyngeal cancer (NPC) in a Caucasian cohort and evaluate factors with prognostic value. METHODS: Between September 2001 and November 2012, 44 NPC patients with a mean age of 57 years underwent 3DCRT at the University Hospital of Ioannina. Nineteen patients (43%) presented with WHO type 1 and 2 histology. Thirty two patients (73%) had advanced-stage disease (stage III/IV). Thirty-one patients (70%) received chemotherapy. The mean total radiotherapy dose prescribed to the planning target volume (PTV) was 67.2 Gy. The daily dose was 1.8 Gy. RESULTS: With a median follow up of 43 months (range 8.4-125), the 4-year local relapse-free (LRFS), nodal relapse-free (NRFS), distant metastases-free survival (DMFS), disease-free survival (DFS) and overall survival (OS) were 90, 87, 91, 80 and 82%, respectively. Histology was a significant prognostic factor concerning overall survival, with worst prognosis in patients with WHO type 1/2 compared to type 3. Age <70 years, absence of retropharyngeal lymph node metastasis, complete response after treatment and the completion of ≥4 cycles of concurrent weekly cisplatin favored overall survival. Fifteen patients (34%) developed grade 3 late side effects (xerostomia: 6, soft tissue fibrosis: 6, hearing loss: 2, brachial plexus neuralgia: 1). CONCLUSION: 3DCRT in our Caucasian cohort, characterized by predominantly advanced-stage disease, combined with chemotherapy, is an effective treatment modality approach in patients with NPC with excellent tolerance.

Prognostic factors in glioblastoma patients managed with radiotherapy combined with temozolomide.

PURPOSE: No consensus on clinicopathologic prognostic factors that predict the outcome of patients with newly diagnosed glioblastoma multiforme (GBM) managed with resection, postoperative radiotherapy (RT) and adjuvant temozolomide (TMZ) exists today. The purpose of this study was to assess the outcome, compliance and toxicity in GBM patients treated with TMZ at our Center, as well as to evaluate factors with prognostic significance. METHODS: 91 GBM patients were enrolled in this retrospective study (2004-2012). 3D-conformal RT was given to a median total dose of 60Gy (daily dose 2Gy). Eighty nine (98%) of the patients received concurrent TMZ (75mg/m²) and 74 (81%) received adjuvant TMZ (150-200mg/m² for 5 days every 28 days) up to 12 cycles. RESULTS: At a mean follow up of 18.6 months, the median overall survival (OS) was 15.1 months. Grade 3/4 haematologic toxicity was observed in 19.8% of the patients while 4 patients (4.4%) experienced grade 3/4 non haematologic toxicity. In univariate analysis, significant correlation was found between OS and no/minor neurologic deficit at diagnosis (p=0.02), acute onset of symptoms (p=0.04) and 6 cycles of adjuvant TMZ (p<0.001). The addition of more than 6 cycles of TMZ did not offer any statistically significant survival benefit. In multivariate analysis, only the absence of major neurologic deficit remained associated with overall survival (p=0.016). CONCLUSION: 3D conformal RT with TMZ achieved acceptable disease control with satisfactory compliance and toxicity. Intact neurologic function was associated with superior outcome, as a surrogate of low tumor burden, early treatment start and/or indolent tumor biology.

Combination treatment for glioblastoma with temozolomide, DFMO and radiation.

PURPOSE: Glioblastoma multiforme (GBM) is the most malignant primary brain tumor with dismal prognosis. This tumor is characterized by extensive heterogeneity, thus is difficult to treat and every established or new treatment faces significant hazard of resistance. Temozolomide (TMZ), an oral alkylating agent, is the first-line treatment for GBM, but resistance to TMZ is a major problem. Herewith, we investigated the combined effect of TMZ, difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, and radiation in GBM cell lines. METHODS: We used the U87G, U251MG and T98G GBM cell lines. A linac 6MV accelerator (Varian Medical Systems) was used for cell irradiation. Viability and proliferation of the cells were examined with trypan blue exclusion assay, crystal violet and xCELLigence system. Cell cycle and activation of caspase-8 were evaluated with flow cytometry. RESULTS: The combination treatment resulted in a consistent higher suppression of proliferation in all cell lines treated and induced a significant higher cell cycle arrest in G2/M phase in U251MG and T98G cell lines. In U251MG cells caspase-8 was increased with each treatment alone, however the combination treatment had lower level of caspase-8 induction, suggesting a co-existence of another mechanism of cell death apart from apoptosis. In T98G cells the combination treatment increased the activation of caspase-8. CONCLUSION: Combination treatment with DFMO, TMZ and radiation significantly reduced cell viability in all cell lines tested. Given that both TMZ and DFMO can be administered orally and are related to minimal toxicities, this combination treatment may be a novel treatment strategy for GBM that deserves further investigation.