ABSTRACT
BACKGROUND: KRAS mutations in NSCLC are associated with a lack of response to epidermal growth factor receptor inhibitors. Selumetinib (AZD6244; ARRY-142886) is an oral selective MEK kinase inhibitor of the Ras/Raf/MEK/ERK pathway. PATIENTS AND METHODS: Advanced nonsmall-cell lung cancer (NSCLC) patients failing one to two prior regimens underwent KRAS profiling. KRAS wild-type patients were randomized to erlotinib (150 mg daily) or a combination of selumetinib (150 mg daily) with erlotinib (100 mg daily). KRAS mutant patients were randomized to selumetinib (75 mg b.i.d.) or the combination. The primary end points were progression-free survival (PFS) for the KRAS wild-type cohort and objective response rate (ORR) for the KRAS mutant cohort. Biomarker studies of ERK phosphorylation and immune subsets were carried out. RESULTS: From March 2010 to May 2013, 89 patients were screened; 41 KRAS mutant and 38 KRAS wild-type patients were enrolled. Median PFS in the KRAS wild-type arm was 2.4 months [95% confidence interval (CI) 1.3-3.7] for erlotinib alone and 2.1 months (95% CI 1.8-5.1) for the combination. The ORR in the KRAS mutant group was 0% (95% CI 0.0% to 33.6%) for selumetinib alone and 10% (95% CI 2.1% to 26.3%) for the combination. Combination therapy resulted in increased toxicities, requiring dose reductions (56%) and discontinuation (8%). Programmed cell death-1 expression on regulatory T cells (Tregs), Tim-3 on CD8+ T cells and Th17 levels were associated with PFS and overall survival in patients receiving selumetinib. CONCLUSIONS: This study failed to show improvement in ORR or PFS with combination therapy of selumetinib and erlotinib over monotherapy in KRAS mutant and KRAS wild-type advanced NSCLC. The association of immune subsets and immune checkpoint receptor expression with selumetinib may warrant further studies.
Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Erlotinib Hydrochloride/administration & dosage , Proto-Oncogene Proteins p21(ras)/genetics , Adult , Aged , Aged, 80 and over , Benzimidazoles/administration & dosage , Carcinoma, Non-Small-Cell Lung/pathology , Disease-Free Survival , Female , Humans , MAP Kinase Kinase Kinase 1/genetics , Male , Middle Aged , Mutation , Protein Kinase Inhibitors/administration & dosageABSTRACT
BACKGROUND: This phase I/II study examined the safety and efficacy of Sepantronium Bromide (S), a small-molecule selective survivin suppressant, administered in combination with carboplatin (C) and paclitaxel (P). PATIENTS AND METHODS: Forty-one patients were treated on study. Twenty-two patients received escalating doses of S (3.6-12 mg/m(2)) and 19 with untreated stage IV non-small-cell lung cancer (NSCLC) were treated with the maximum tolerated dose of 10 mg/m(2) in combination with standard doses of C (AUC6) and P (200 mg/m(2)) for six cycles. S was administered as a continuous intravenous infusion (CIVI) over 72 h in 21-day treatment cycles. Study end points included safety and toxic effect, response rate, progression-free and overall survival (PFS and OS), as well as exploratory pharmacodynamic correlates. RESULTS: Treatment with S was well tolerated, and toxic effects were mostly hematological in the phase II study. Two (11%) partial responses were observed with a median PFS of 5.7 months and median OS 16.1 months. Pharmacodynamic analysis did not demonstrate an association with response. CONCLUSION: The combination of S (10 mg/m(2)/day 72-h CIVI) administered with C and P every 3 weeks exhibited a favorable safety profile but failed to demonstrate an improvement in response rate in advanced NSCLC. CLINICAL TRIAL NUMBER: NCT01100931.
Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Imidazoles/therapeutic use , Inhibitor of Apoptosis Proteins/antagonists & inhibitors , Lung Neoplasms/drug therapy , Naphthoquinones/therapeutic use , Adult , Aged , Antineoplastic Agents, Phytogenic/adverse effects , Antineoplastic Agents, Phytogenic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Apoptosis/drug effects , Carboplatin/adverse effects , Carboplatin/therapeutic use , Disease-Free Survival , Female , Humans , Imidazoles/adverse effects , Imidazoles/blood , Male , Middle Aged , Naphthoquinones/adverse effects , Naphthoquinones/blood , Paclitaxel/adverse effects , Paclitaxel/therapeutic use , Survival , Survivin , Treatment OutcomeABSTRACT
Atm, the gene mutated in ataxia-telangiectasia (AT) patients, is an essential component of the signal transduction pathway that responds to DNA damage due to ionizing radiation (IR). We attenuated ATM protein expression in human glioblastoma cells by expressing antisense RNA to a functional domain of the atm gene. While ATM expression decreased, constitutive expression of p53 and p21 increased. Irradiated ATM-attenuated cells failed to induce p53, demonstrated radioresistant DNA synthesis, and increased radiosensitivity. Antisense-ATM gene therapy in conjunction with radiation therapy may provide a novel strategy for the treatment of cancer.
