Orthotopic Model Of Human Lung Cancer Research Articles

Abstract 1042: Maintenance or switch maintenance therapy with selumetinib or cediranib after chemoradiation prolongs survival in an orthotopic human lung cancer model.

Abstract Background The outcome of lung cancer is poor and new therapies are needed. Selumetinib (AZD6244, ARRY-142886) and cediranib are potent MEK 1/2 and VEGFR tyrosine kinase inhibitors, respectively. In the current study, we evaluated the therapeutic efficacy of each with chemoradiation followed by maintenance therapy in a KRAS mutant orthotopic human non-small cell lung cancer model. Methods NCI-H460 lung cancer cells were injected into the lungs of mice. Mice were randomized (32/group) to therapy with radiation (20 Gy in 5 fractions) + paclitaxel (200 μg/week), radiation, paclitaxel, and selumetinib (25 mg/kg/day) or cediranib (3 mg/kg/day), or vehicle control (n=8). When controls became moribund, 8 mice from each group were sacrificed and assessed for tumor burden. The remaining mice were re-randomized to switch or continuation maintenance with selumetinib or cediranib or vehicle (8/group). Mice were sacrificed when they became moribund and tumor tissues were subjected to immunohistologic analyses. Results After the initiation phase, chemoradiation reduced tumor volume by 78% (p = 0.0002 vs control) with modest effects on regional metastases. The anti-tumor and anti-metastatic effects of chemoradiation were markedly enhanced by selumetinib or cediranib with a reduced total tumor volume of 96% and 99% (p = 0.002 or 0.0002) and primary lung tumor volume of 88% or 98% (p = 0.002 and 0.0002) compared to control. Trimodality therapy inhibited angiogenesis and tumor proliferation and increased tumor and endothelial cell apoptosis. In the maintenance phase, selumetinib or cediranib after chemoradiation prolonged survival compared to vehicle with a median survival of 41 or 43 vs 33 days (p = 0.008 or 0.005, respectively). Maintenance selumetinib or cediranib after chemoradiation + selumetinib resulted in a median survival of 46.5 or 53 vs 36.5 days for control (p = 0.001 or 0.0004, respectively). Maintenance selumetinib or cediranib after chemoradiation + cediranib improved survival by 52 or 67 vs 39 days for control (p = 0.0002). There was no significant survival difference for switch or continuation maintenance. The longest survival (105 days) was observed for selumetinib maintenance after chemoradiation + cediranib. Failure patterns with maintenance therapy included regional and distant metastases with brain, bone, and adrenal metastases observed. Conclusions Selumetinib or cediranib substantially enhanced the effects of chemoradiation in an orthotopic human lung cancer model. Maintenance therapy with selumetinib or cediranib after trimodality therapy significantly prolonged survival. Mice developed regional and distant metastatic disease in patterns similar to those observed clinically. These data provide a basis for clinical trials and our model allows for the study of failure and resistance patterns with maintenance therapy in lung cancer. Citation Format: Osamu Takahashi, Ritsuko U. Komaki, Juliane M. Jürgensmeier, Paul D. Smith, Ignacio I. Wistuba, Ramesh C. Tailor, Joerg J. Jacoby, Maria V. Korshunova, Yong Bae Kim, Baruch Erez, Roy S. Herbst, Michael S. O'Reilly. Maintenance or switch maintenance therapy with selumetinib or cediranib after chemoradiation prolongs survival in an orthotopic human lung cancer model. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1042. doi:10.1158/1538-7445.AM2013-1042

Abstract 5123: In vitro culture for characterization of circulating GFP-expressing tumor cells in orthotopic lung cancer models .

Abstract In the present study circulating tumor cells (CTCs) were isolated from H460-RFP orthotopic human lung cancer model in mice. In vitro culture of CTCs has enabled us comparison of the chemosensitivity of tumor cells from primary H460 culture and of CTCs solated from blood grown in vitro. Cell line H460-RFP human lung cancer cells were grown to 70-80% confluence. Primary tumor were grown after subcutaneous injection of cultured cells. Fragments of tumor tissue (1 mm × 1 mm) were implanted into the lungs of nude mice. At 14 days, the mice were sacrificied and blood was taken by cardiac puncture for CTC-analysis. The blood (0.5 ml), obtained by cardiac puncture, was put into an EDTA tube (BD) and the CTC cells were enriched by immunomagnetic separation targeted to eptihelial antigens. The enriched fraction or whole blood was put into culture. Cell growth was then monitored by fluorescence microscopy. The isolation and culture of the fluorescent CTC will enable their further characterization. Citation Format: Katarína Kološtová, Marián Liberko, Eva Hroncová, Robert M. Hoffman, Vladimír Bobek. In vitro culture for characterization of circulating GFP-expressing tumor cells in orthotopic lung cancer models . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5123. doi:10.1158/1538-7445.AM2013-5123

In vitro culturing of circulating tumor cells in lung cancer management

Introduction: In the present study circulating tumor cells (CTCs) have been isolated from H460-RFP orthotopic human lung cancer model in mice. In vitro culture of CTCs has enabled us to introduce additional testing describing the CTC-character.

Abstract 1397: VEGFR signaling inhibition by cediranib enhances the antitumor and anti-metastatic effects of chemotherapy and radiation in an orthotopic human lung cancer model

Abstract Introduction: Cediranib (AZD2171, RECENTIN™) is a potent and orally available VEGF receptor signaling inhibitor in clinical development. This study evaluated the therapeutic efficacy and radiosensitizing effects of cediranib and paclitaxel in an orthotopic human lung cancer model that closely mimics clinical patterns of lung cancer progression. Methods: PC14PE6 human lung adenocarcinoma cells were injected into the left lungs of nude mice. Lung tumors were observed in all 5 mice sacrificed 14 days after tumor implant. The remaining mice were randomized (8/group) to receive vehicle (control), cediranib (3 mg/kg/day po), paclitaxel (200 µg/week ip), radiation to the left lung and mediastinum (20 Gy in 5 fractions over 2 weeks), or radiation with cediranib and/or paclitaxel. After 21 days, when control mice showed signs of becoming moribund, all mice were sacrificed and assessed for lung tumor burden and locoregional metastasis. Lung tumors and adjacent tissues were excised and analyzed by immunohistochemistry. Results: Radiation or cediranib monotherapy reduced median lung tumor volume by 80% (P=0.0016 vs control) and 82% (P=0.0011 vs control), respectively, significantly reduced mediastinal metastasis, and prevented pleural effusion. Paclitaxel reduced median tumor volume by 33% with a modest effect on lymphatic metastasis and pleural effusion. Cediranib substantially enhanced the antitumor and anti-metastatic effects of radiation therapy with a reduction in median primary tumor volume of 99.8% (P=0.0006) and left lung weight of 93% (P=0.0007) compared with control, with no evidence of mediastinal metastasis (P=0.0098). The effects of radiation therapy were only marginally improved by paclitaxel. Trimodality therapy with cediranib, paclitaxel and radiation resulted in the near complete prevention of lung tumor growth and metastasis. All treatments were well tolerated. Immunohistochemical analyses of lung tumors revealed that radiation or cediranib significantly reduced microvessel density and increased tumor and endothelial cell apoptosis and the antiangiogenic and apoptotic effects were substantially enhanced when these treatments were combined. Conclusions: In an orthotopic lung cancer model, targeted therapy against VEGFR by cediranib inhibits tumor growth and metastasis and enhances the effects of radiation therapy. The radiosensitizing effects of cediranib on lung tumors and their vasculature were superior to paclitaxel. Trimodality therapy with cediranib, paclitaxel, and radiation resulted in the near complete suppression of lung tumor growth and metastasis with markedly enhanced antiangiogenic and apoptotic effects. The combination of cediranib with radiation and chemotherapy is a potentially promising therapy for lung cancer and our data provide the basis for clinical trials in lung cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1397.

Targeted Therapy Against VEGFR and EGFR With ZD6474 Enhances the Therapeutic Efficacy of Irradiation in an Orthotopic Model of Human Non–Small-Cell Lung Cancer

Conventional therapies for patients with lung cancer have reached a therapeutic plateau. We therefore evaluated the feasibility of combined vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and epidermal growth factor (EGF) receptor (EGFR) targeting with radiation therapy in an orthotopic model that closely recapitulates the clinical presentation of human lung cancer. Effects of irradiation and/or ZD6474, a small-molecule inhibitor of VEGFR2 and EGFR tyrosine kinases, were studied in vitro for human lung adenocarcinoma cells by using proliferation and clonogenic assays. The feasibility of combining ZD6474 with radiation therapy was then evaluated in an orthotopic model of human lung adenocarcinoma. Lung tumor burden and spread within the thorax were assessed, and tumor and adjacent tissues were analyzed by means of immunohistochemical staining for multiple parameters, including CD31, VEGF, VEGFR2, EGF, EGFR, matrix metalloproteinase-2 and -9, and basic fibroblast growth factor. ZD6474 enhanced the radioresponse of NCI-H441 human lung adenocarcinoma cells by a factor of 1.37 and markedly inhibited sublethal damage repair. In vivo, the combined blockade of VEGFR2 and EGFR by ZD6474 blocked pleural effusion formation and angiogenesis and enhanced the antivascular and antitumor effects of radiation therapy in the orthotopic human lung cancer model and was superior to chemoradiotherapy. When radiation therapy is combined with VEGFR2 and EGFR blockade, significant enhancement of antiangiogenic, antivascular, and antitumor effects are seen in an orthotopic model of lung cancer. These data provide support for clinical trials of biologically targeted and conventional therapies for human lung cancer.

1106 ORAL Tumour anti-vascular effects of radiotherapy (RT) in lung cancer measured using quantitative whole tumour perfusion CT (p-CT)

Conventional therapies for patients with lung cancer have reached a therapeutic plateau. We therefore evaluated the feasibility of combined vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and epidermal growth factor (EGF) receptor (EGFR) targeting with radiation therapy in an orthotopic model that closely recapitulates the clinical presentation of human lung cancer.Effects of irradiation and/or ZD6474, a small-molecule inhibitor of VEGFR2 and EGFR tyrosine kinases, were studied in vitro for human lung adenocarcinoma cells by using proliferation and clonogenic assays. The feasibility of combining ZD6474 with radiation therapy was then evaluated in an orthotopic model of human lung adenocarcinoma. Lung tumor burden and spread within the thorax were assessed, and tumor and adjacent tissues were analyzed by means of immunohistochemical staining for multiple parameters, including CD31, VEGF, VEGFR2, EGF, EGFR, matrix metalloproteinase-2 and -9, and basic fibroblast growth factor.ZD6474 enhanced the radioresponse of NCI-H441 human lung adenocarcinoma cells by a factor of 1.37 and markedly inhibited sublethal damage repair. In vivo, the combined blockade of VEGFR2 and EGFR by ZD6474 blocked pleural effusion formation and angiogenesis and enhanced the antivascular and antitumor effects of radiation therapy in the orthotopic human lung cancer model and was superior to chemoradiotherapy.When radiation therapy is combined with VEGFR2 and EGFR blockade, significant enhancement of antiangiogenic, antivascular, and antitumor effects are seen in an orthotopic model of lung cancer. These data provide support for clinical trials of biologically targeted and conventional therapies for human lung cancer.

Therapeutic effect of a retroviral wild-type p53 expression vector in an orthotopic lung cancer model.

Mutations in the p53 tumor suppressor gene (also known as TP53) are common in human lung cancers. The wild-type form of p53 is dominant over the mutant; thus, restoration of wild-type p53 function in lung cancer cells may suppress their growth as tumors. We investigated the therapeutic efficacy of direct administration of a retroviral wild-type p53 (wt-p53) expression vector (LNp53B) in an orthotopic human lung cancer model in nu/nu mice. Proliferation of H226Br cells was determined by cell counting after infection with LNp53B in vitro. Irradiated (350 cGy) female BALB/c nu/nu mice were inoculated intratracheally with 2 x 10(6) H226Br cells (whose p53 gene has a homozygous mutation at codon 254) and treated beginning 3 days later with an intratracheal instillation of LNp53B retroviral supernatant for 3 days. Infection with LNp53B inhibited proliferation of H226Br cells in vitro. Thirty days after tumor cell inoculation, 62%-80% of the control mice showed macroscopic tumors of the right main stem bronchus. LNp53B suppressed H226Br tumor formation in 62%-100% of mice, and the effect was abrogated by dilution of the retroviral supernatant with inactive vector. Direct administration of a retroviral vector expressing wt-p53 may inhibit local growth in vivo of human lung cancer cells with abnormal p53 expression. Development of gene-replacement treatment strategies based on the type of mutations found in target cancers is warranted and may lead to the development of new adjunctive therapies and gene-specific prevention strategies for lung cancer.