gdc-0449 and Carcinoma--Non-Small-Cell-Lung

Tyrosine kinase inhibitors (TKIs) of the EGF receptor (EGFR) have provided a significant improvement in the disease outcome of nonsmall cell lung cancer (NSCLC). Unfortunately, resistance to these agents frequently occurs, and it is often related to the activation of the Hedgehog (Hh) and MET signaling cascades driving the epithelial-to-mesenchymal transition (EMT). Because the concomitant inhibition of both Hh and MET pathways restores the sensitivity to anti-EGFR drugs, here we aimed at discovering the first compounds that block simultaneously MET and SMO. By using an "in silico drug repurposing" approach and by validating our predictions both in vitro and in vivo, we identified a set of compounds with the desired dual inhibitory activity and enhanced antiproliferative activity on EGFR TKI-resistant NSCLC. The identification of the known MET TKIs, glesatinib and foretinib, as negative modulators of the Hh pathway, widens their application in the context of NSCLC.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Drug Repositioning; Drug Resistance, Neoplasm; ErbB Receptors; Female; HEK293 Cells; Humans; Lung; Lung Neoplasms; Mice, Inbred BALB C; Mice, Nude; Molecular Docking Simulation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-met; Smoothened Receptor

Chemoresistance is a major challenge in the treatment of advanced non-small-cell lung cancer (NSCLC). Because the Sonic hedgehog (Shh) pathway is reactivated in NSCLC, we investigated an association between chemoresistance and Shh activation.. From a cohort of 178 patients with advanced NSCLC treated with platinum-based chemotherapy as first-line treatment, we selected all surgical tumor samples at diagnosis (n = 36). Shh activation was evaluated through Gli1 and Gli2 expression using immunohistochemistry (quantitative score). In vitro treatment studies with cisplatin or vismodegib (Shh pathway inhibitor), or both, were performed on NSCLC cell lines (H322 and A549) and primary cultures from patients with sarcomatoid carcinoma (n = 4).. Of the 36 patients, 12 had NSCLC refractory to chemotherapy (R-patients, 33.3%) and 24 had controlled disease (C-patients). Gli1 expression did not differ between the R- and C-patients (P = .35). Gli2 expression was more often positive in the R-patients (41.7% vs. 8.3%; P = .02). Progression-free survival (PFS) and overall survival (OS) in patients with a Gli2-positive score was 2.1 and 8.0 months, respectively, compared with 6.7 and 18.0 months for patients with a Gli2-negative score (P = .03 and P = .002, respectively). On multivariate analysis, the Gli2 score correlated independently with PFS (hazard ratio [HR], 2.64; 95% confidence interval [CI], 1.05-6.63; P = .04) and OS (HR, 4.36; 95% CI, 1.67-11.36; P = .003). The sarcomatoid carcinoma cell lines were more resistant to cisplatin than were the H838 and A549 cell lines. The cisplatin-vismodegib combination displayed a synergistic cytotoxic effect in the most chemoresistant cells in vitro.. The Shh pathway is associated with resistance to platinum-based chemotherapy in NSCLC.

Topics: Adult; Anilides; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cohort Studies; Drug Resistance, Neoplasm; Female; Hedgehog Proteins; Humans; Kruppel-Like Transcription Factors; Male; Middle Aged; Neoplasm Staging; Nuclear Proteins; Platinum Compounds; Pyridines; Signal Transduction; Survival Analysis; Transcriptional Activation; Zinc Finger Protein GLI1; Zinc Finger Protein Gli2

Epidermal growth factor receptor- tyrosine kinase inhibitors (EGFR-TKIs) benefit Non-small cell lung cancer (NSCLC) patients, and an EGFR-TKIi erlotinib, is approved for patients with recurrent NSCLC. However, resistance to erlotinib is a major clinical problem. Earlier we have demonstrated the role of Hedgehog (Hh) signaling in Epithelial-to-Mesenchymal transition (EMT) of NSCLC cells, leading to increased proliferation and invasion. Here, we investigated the role of Hh signaling in erlotinib resistance of TGF-β1-induced NSCLC cells that are reminiscent of EMT cells.. Hh signaling was inhibited by specific siRNA and by GDC-0449, a small molecule antagonist of G protein coupled receptor smoothened in the Hh pathway. Not all NSCLC patients are likely to benefit from EGFR-TKIs and, therefore, cisplatin was used to further demonstrate a role of inhibition of Hh signaling in sensitization of resistant EMT cells. Specific pre- and anti-miRNA preparations were used to study the mechanistic involvement of miRNAs in drug resistance mechanism.. siRNA-mediated inhibition as well as pharmacological inhibition of Hh signaling abrogated resistance of NSCLC cells to erlotinib and cisplatin. It also resulted in re-sensitization of TGF-β1-induced A549 (A549M) cells as well the mesenchymal phenotypic H1299 cells to erlotinib and cisplatin treatment with concomitant up-regulation of cancer stem cell (CSC) markers (Sox2, Nanog and EpCAM) and down-regulation of miR-200 and let-7 family miRNAs. Ectopic up-regulation of miRNAs, especially miR-200b and let-7c, significantly diminished the erlotinib resistance of A549M cells. Inhibition of Hh signaling by GDC-0449 in EMT cells resulted in the attenuation of CSC markers and up-regulation of miR-200b and let-7c, leading to sensitization of EMT cells to drug treatment, thus, confirming a connection between Hh signaling, miRNAs and drug resistance.. We demonstrate that Hh pathway, through EMT-induction, leads to reduced sensitivity to EGFR-TKIs in NSCLCs. Therefore, targeting Hh pathway may lead to the reversal of EMT phenotype and improve the therapeutic efficacy of EGFR-TKIs in NSCLC patients.

Topics: Anilides; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cisplatin; Drug Resistance, Neoplasm; Epithelial-Mesenchymal Transition; ErbB Receptors; Erlotinib Hydrochloride; Gene Knockdown Techniques; Hedgehog Proteins; Humans; Lung Neoplasms; MicroRNAs; Pyridines; Quinazolines; RNA, Small Interfering; Signal Transduction; Transfection

Despite improvements in chemoradiation, local control remains a major clinical problem in locally advanced non-small cell lung cancer. The Hedgehog pathway has been implicated in tumor recurrence by promoting survival of tumorigenic precursors and through effects on tumor-associated stroma. Whether Hedgehog inhibition can affect radiation efficacy in vivo has not been reported.. We evaluated the effects of a targeted Hedgehog inhibitor (HhAntag) and radiation on clonogenic survival of human non-small cell lung cancer lines in vitro. Using an A549 cell line xenograft model, we examined tumor growth, proliferation, apoptosis, and gene expression changes after concomitant HhAntag and radiation. In a transgenic mouse model of Kras(G12D)-induced and Twist1-induced lung adenocarcinoma, we assessed tumor response to radiation and HhAntag by serial micro-computed tomography (CT) scanning.. In 4 human lung cancer lines in vitro, HhAntag showed little or no effect on radiosensitivity. By contrast, in both the human tumor xenograft and murine inducible transgenic models, HhAntag enhanced radiation efficacy and delayed tumor growth. By use of the human xenograft model to differentiate tumor and stromal effects, mouse stromal cells, but not human tumor cells, showed significant and consistent downregulation of Hedgehog pathway gene expression. This was associated with increased tumor cell apoptosis.. Targeted Hedgehog pathway inhibition can increase in vivo radiation efficacy in lung cancer preclinical models. This effect is associated with pathway suppression in tumor-associated stroma. These data support clinical testing of Hedgehog inhibitors as a component of multimodality therapy for locally advanced non-small cell lung cancer.

Topics: Adenocarcinoma; Anilides; Animals; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Survival; Female; Hedgehog Proteins; Humans; Lung Neoplasms; Mice; Mice, Nude; Mice, Transgenic; Neoplasm Proteins; Pyridines; Radiation Tolerance; Transplantation, Heterologous

HhAntag691 (GDC-0449), a low-molecular weight inhibitor of the tumor-promoting hedgehog (Hh) signaling pathway, has been used to treat medulloblastoma in animal models and has recently entered clinical trials for a variety of solid tumors. Here, we show that HhAntag691 inhibits multiple ATP-binding cassette (ABC) transporters. ATP-binding cassette transporters are within a family of membrane proteins, the overexpression of which is associated with multidrug resistance, a major impediment to successful cancer treatment. HhAntag691 is a potent inhibitor of two ABC transporters, ABCG2/BCRP and ABCB1/Pgp, and is a mild inhibitor of ABCC1/MRP1. In ABCG2-overexpressing HEK293 cells, HhAntag691 increased retention of the fluorescent ABCG2 substrate BODIPY-prazosin and resensitized these cells to mitoxantrone, an antineoplastic ABCG2 substrate. In Madin-Darby canine kidney II cells engineered to overexpress Pgp or MRP1, HhAntag691 increased the retention of calcein-AM and resensitized them to colchicine. HhAntag691 also resensitized human non-small cell lung carcinoma cells NCI-H460/par and NCI-H460/MX20, which overexpress ABCG2 in response to mitoxantrone, to mitoxantrone, and to topotecan or SN-38. The IC(50) values of HhAntag691 for inhibition of ABCG2 and Pgp were approximately 1.4 and approximately 3.0 microM, respectively. Because ABC transporters are highly expressed at the blood-brain barrier and on many tumor cells, they contribute significantly to treatment failure of many types of cancer, particularly of those within the neuraxis. In addition to its effect on Hh signaling, the ability of HhAntag691 and related compounds to inhibit two key ABC transporters could contribute to their effectiveness in treating malignancies.

Topics: Anilides; Animals; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; ATP Binding Cassette Transporter, Subfamily G, Member 2; ATP-Binding Cassette Transporters; Benzimidazoles; Carcinoma, Non-Small-Cell Lung; Cells, Cultured; Colchicine; Dogs; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Drug Resistance, Neoplasm; Hedgehog Proteins; Humans; Lung Neoplasms; Multidrug Resistance-Associated Proteins; Neoplasm Proteins; Pyridines; Signal Transduction