Project description:Insulin-like growth factor receptor-1 (IGF-1R) inhibition could be a relevant therapeutic approach in small cell lung cancer (SCLC) given the importance of an IGF-1R autocrine loop and its role in DNA damage repair processes. We assessed IGF-1R and pAkt protein expression in 83 SCLC human specimens. The efficacy of R1507 (a monoclonal antibody directed against IGF-1R) alone or combined with cisplatin or ionizing radiation (IR) was evaluated in H69, H146 and H526 cells in vitro and in vivo. Innovative genomic and functional approaches were conducted to analyze the molecular behavior under the different treatment conditions. A total of 53% and 37% of human specimens expressed IGF-1R and pAkt, respectively. R1507 demonstrated single agent activity in H146 and H526 cells but not in H69 cells. R1507 exhibited synergistic effects with both Cisplatin and IR in vitro. The triple combination R1507-Cisplatin-IR led to a dramatic delay in tumor growth compared to Cisplatin-IR in H526 cells. Analyzing the apparent absence of antitumoral effect of R1507 alone in vivo, we observed a transient reduction of IGF-1R staining intensity in vivo, concomitant to the activation of multiple cell surface receptors and intracellular proteins involved in proliferation, angiogenesis and survival. Finally, we identified that the nucleotide excision repair pathway (NER) was mediated after exposure to R1507-CDDP and R1507-IR in vitro and in vivo. In conclusion, adding R1507 to the current standard Cisplatin-IR doublet reveals remarkable chemo- and radiosensitizing effects in selected SCLC models and warrants to be investigated in the clinical setting. We used microarrays to investigate the effect of IGF-1R targetting on the global gene expression. Gene expression data from H526 xenografts under various treatment and time conditions Total mRNA from 33 NCI-H526 SCLC (small-cell lung cancer) xenografts was hybridized to Affymetrix HGU133 Plus 2.0 expression arrays. Log2 gene expression values were calculated using RMA. (A) To identify the molecular mechanisms involved in the response to R1507 alone along the treatment time, we performed global gene expression profiling in H526 xenografts at the following time points: baseline (vehicle), R1507 day 1 and R1507 day 7. (B) To identify the molecular mechanisms involved in the response to CDDP- and IR-R1507 combinations, we performed global gene expression profiling on mice bearing H526 xenografts treated with the following treatment conditions: vehicle, R1507 CDDP, IR, CDDP-R1507 and IR-R1507.
Project description:Lung cancer is the leading cause of cancer death in the United States. Among the various subtypes of lung cancers, pulmonary neuroendocrine (NE) cancer, including small cell lung cancer (SCLC) and NE-non-small cell lung cancer (NE-NSCLC), is a particularly aggressive malignancy that is distinct from classic non–small cell lung cancer (NSCLC) in its metastatic potential and treatment response. Recently, the lineage-specific transcription factors Achaete-scute homolog 1 (ASCL1), NEUROD1, and POU2F3 have been reported to identify heterogeneity in pulmonary NE cancers. These transcription factors bind different genomic loci to regulate distinct gene programs in pulmonary NE cancers. However, the signaling pathways downstream of these transcription factors that distinguish these pulmonary NE cancer subtypes are not well characterized. Regulated protein secretion is critically involved in cell signaling and cell-cell communication events, and is known to be a hallmark associated with pulmonary NE tumors. Using a large-scale mass spectrometric approach, we performed quantitative secretomic analysis 13 cell lines including a pair of isogenic cell lines, i.e., an immortalized human bronchial epithelial cell and an ASCL1high NE NSCLC line. This panel also contained 6 additional ASCL1High and 5 NEUROD1High NE-lung cancer cell lines. From the conditioned media of the 13 cell lines, we identified and quantified 1,626 proteins. The NE-specific secretome is associated with a number of biological processes related to neurodevelopment. Further analysis of the upregulated proteins in ASCL1High subtype NE-lung cancer cells leads to the identification of IGFBP5 being a specific secreted marker for ASCL1High pulmonary NE cancer cells. Furthermore, IGFBP5 is also upregulated in the serum of a genetically modified mouse model of ASCL1High SCLC, as well as in human ASCL1High SCLC tumors. Mechanistically, ASCL1 binds to E-box elements in the IGFBP5 gene and directly regulates its transcription. Knockdown of ASCL1 in SCLC decreases IGFBP5 expression, which, in turn, leads to hyperactivation of the IGF-1R pathway. Pharmacological co-targeting of ASCL1 and IGF-1R signaling results in markedly synergistic, growth inhibitory effects in ASCL1High SCLC both in vitro and in vivo. Together, our quantitative proteomic analysis identifies a novel secreted marker and a new combination therapy for ASCL1High pulmonary NE cancer cells. In addition, we expect that the data sets will serve as an invaluable resource, providing the foundation for future mechanistic studies and biomarker discovery that helps delineate the molecular underpinnings of pulmonary NE tumors.
Project description:Lung cancer is the leading cause of cancer death in the United States. Among the various subtypes of lung cancers, pulmonary neuroendocrine (NE) cancer, including small cell lung cancer (SCLC) and NE-non-small cell lung cancer (NE-NSCLC), is a particularly aggressive malignancy that is distinct from classic non–small cell lung cancer (NSCLC) in its metastatic potential and treatment response. Recently, the lineage-specific transcription factors Achaete-scute homolog 1 (ASCL1), NEUROD1, and POU2F3 have been reported to identify heterogeneity in pulmonary NE cancers. These transcription factors bind different genomic loci to regulate distinct gene programs in pulmonary NE cancers. However, the signaling pathways downstream of these transcription factors that distinguish these pulmonary NE cancer subtypes are not well characterized. Regulated protein secretion is critically involved in cell signaling and cell-cell communication events, and is known to be a hallmark associated with pulmonary NE tumors. Using a large-scale mass spectrometric approach, we performed quantitative secretomic analysis 13 cell lines including a pair of isogenic cell lines, i.e., an immortalized human bronchial epithelial cell and an ASCL1high NE NSCLC line. This panel also contained 6 additional ASCL1High and 5 NEUROD1High NE-lung cancer cell lines. From the conditioned media of the 13 cell lines, we identified and quantified 1,626 proteins. The NE-specific secretome is associated with a number of biological processes related to neurodevelopment. Further analysis of the upregulated proteins in ASCL1High subtype NE-lung cancer cells leads to the identification of IGFBP5 being a specific secreted marker for ASCL1High pulmonary NE cancer cells. Furthermore, IGFBP5 is also upregulated in the serum of a genetically modified mouse model of ASCL1High SCLC, as well as in human ASCL1High SCLC tumors. Mechanistically, ASCL1 binds to E-box elements in the IGFBP5 gene and directly regulates its transcription. Knockdown of ASCL1 in SCLC decreases IGFBP5 expression, which, in turn, leads to hyperactivation of the IGF-1R pathway. Pharmacological co-targeting of ASCL1 and IGF-1R signaling results in markedly synergistic, growth inhibitory effects in ASCL1High SCLC both in vitro and in vivo. Together, our quantitative proteomic analysis identifies a novel secreted marker and a new combination therapy for ASCL1High pulmonary NE cancer cells. In addition, we expect that the data sets will serve as an invaluable resource, providing the foundation for future mechanistic studies and biomarker discovery that helps delineate the molecular underpinnings of pulmonary NE tumors.
Project description:Insulin-like growth factor receptor-1 (IGF-1R) inhibition could be a relevant therapeutic approach in small cell lung cancer (SCLC) given the importance of an IGF-1R autocrine loop and its role in DNA damage repair processes. We assessed IGF-1R and pAkt protein expression in 83 SCLC human specimens. The efficacy of R1507 (a monoclonal antibody directed against IGF-1R) alone or combined with cisplatin or ionizing radiation (IR) was evaluated in H69, H146 and H526 cells in vitro and in vivo. Innovative genomic and functional approaches were conducted to analyze the molecular behavior under the different treatment conditions. A total of 53% and 37% of human specimens expressed IGF-1R and pAkt, respectively. R1507 demonstrated single agent activity in H146 and H526 cells but not in H69 cells. R1507 exhibited synergistic effects with both Cisplatin and IR in vitro. The triple combination R1507-Cisplatin-IR led to a dramatic delay in tumor growth compared to Cisplatin-IR in H526 cells. Analyzing the apparent absence of antitumoral effect of R1507 alone in vivo, we observed a transient reduction of IGF-1R staining intensity in vivo, concomitant to the activation of multiple cell surface receptors and intracellular proteins involved in proliferation, angiogenesis and survival. Finally, we identified that the nucleotide excision repair pathway (NER) was mediated after exposure to R1507-CDDP and R1507-IR in vitro and in vivo. In conclusion, adding R1507 to the current standard Cisplatin-IR doublet reveals remarkable chemo- and radiosensitizing effects in selected SCLC models and warrants to be investigated in the clinical setting. We used microarrays to investigate the effect of IGF-1R targetting on the global gene expression.
Project description:Gene expression was measured on the Affymetrix platform in primary xenografts, xenograft-derived cell lines, secondary xenografts, normal lung, and primary tumors obtained from chemotherapy naive Small Cell Lung Cancer (SCLC). The SCLC primary xenografts were serially propagated in vivo in immunodeficient mice. Cell lines were derived from each xenograft and grown for 6 months using conventional tissue culture conditions. Secondary xenografts were obtained from cell cultures by re-implantation in immunodeficient mice. Such SCLC laboratory models were analyzed along with conventional SCLC cell lines and the derivative secondary xenografts, with normal lung and primary tumors, to assess irreversible gene expression changes induced by culturing conditions. Experiment Overall Design: SCLC primary xenografts were compared to the corresponding xenograft-derived cell lines, and to the secondary xenografts established from the cell lines using the Affymetrix GeneChip Human Genome U133 Plus 2.0 Array. Gene expression from SCLC primary tumors was measured using the Affymetrix GeneChip Human Genome U133A 2.0 Array. 3 datasets: GSM380476-GSM380512, GSM380513-GSM380516, and GSM380517-GSM380520
Project description:The important role of IGF-1R in cancers has been well established. Classical model involves IGF-1/2 binding to IGF-1R, following activation of the PI3K/Akt pathway, thereby promoting cell proliferation, apoptosis inhibition and treatment resistance. While IGF-1R has become a promising target for cancer therapy, clinical disclosures subsequently have been less encouraging. The question is whether targeting IGF/IGF-1R still holds therapeutic potential. Here we show a novel mechanism that knockdown IGF-1R surprisingly triggers cytoplasmic viral RNA sensors MDA5 and RIG-1, leading to mitochondrial apoptosis in cancer. We analyzed MDA5 and RIG-1 in the intestinal epithelium of IGF-1R knockdown mice. Igf1r+/- mice demonstrated higher MDA5 and RIG-1 than WT mice. IGF-1R knockdown-triggered MDA5 and RIG-1 was further analyzed in human cancer and normal cells. Increased MDA5 and RIG-1 were clearly seen in the cytoplasm identified by immunofluoresce in the cells silenced IGF-1R. Block off IGF-1R downstream PI3K/Akt did not impact on MDA5 and RIG-1 expression. IGF-1R knockdown-triggered MDA5 and RIG-1 and their signaling pathways were similar to those of viral RNA mimetic poly(I:C) had. IGF-1R knockdown-triggered MDA5 and RIG-1 led to cancer apoptosis through activation of the mitochondrial pathway. In vivo assay, Igf1r+/- mice strongly resisted AOM-induced colonic tumorigenesis through triggering MDA¬5- and RIG-1-mediated apoptosis. Notably, RIG-I and MDA5-mediated proapoptotic signaling pathway is preferential active in cancer cells. These data suggest that targeting IGF-1R-triggered MDA5 and RIG-1 might have therapeutic potential for cancer treatment.
Project description:Gene expression was measured on the Affymetrix platform in primary xenografts, xenograft-derived cell lines, secondary xenografts, normal lung, and primary tumors obtained from chemotherapy naive Small Cell Lung Cancer (SCLC). The SCLC primary xenografts were serially propagated in vivo in immunodeficient mice. Cell lines were derived from each xenograft and grown for 6 months using conventional tissue culture conditions. Secondary xenografts were obtained from cell cultures by re-implantation in immunodeficient mice. Such SCLC laboratory models were analyzed along with conventional SCLC cell lines and the derivative secondary xenografts, with normal lung and primary tumors, to assess irreversible gene expression changes induced by culturing conditions.
Project description:The goal of this study was to characterize and classify pulmonary neuroendocrine tumors based on Array Comparative Genomic Hybridization (aCGH). Using aCGH, we performed karyotype analysis of 33 small cell lung cancer (SCLC) tumors, 13 SCLC cell lines, 19 bronchial carcinoids, and 9 gastrointestinal (GI) carcinoids. In contrast to the relatively stable karyotypes of carcinoid tumors, the karyotypes of SCLC tumors and cell lines were highly aberrant. High copy number (CN) gains were detected in SCLC tumors and cell lines in cytogenetic bands encoding JAK2, FGFR1, and MYC family members. In some of those samples, the CN of these genes exceeded 100, suggesting that they could represent driver alterations and potential drug targets in subgroups of SCLC patients. Recurrent CN alterations of a total of 203 genes, including the RB1 gene, and 59 microRNAs, most of which locate in the DLK1-DIO3 domain, were observed in SCLC tumors, bronchial carcinoids and carcinoids of GI origin; in contrast, CN alterations of the TP53 gene and the MYC family members were observed more frequently in SCLC. These findings suggest the existence of partially shared tumor-specific CN alterations in these tumors. Furthermore, we demonstrated that the aCGH profile of SCLC cell lines highly resemble that of clinical SCLC specimens. Finally, by analyzing potential drug targets, we provide a genomics based rationale for targeting the AKT-mTOR and apoptosis pathways in SCLC. Carcinoids, including 19 bronchial carcinoids and 9 carcinoid of gastrointestinal origin, and small cell lung cancer, including 33 patients' tumor samples and 13 cell line samples, were compared.
Project description:Characterization of 63 small cell lung cancer (SCLC) cell lines and a comparator set of non-small cell lung cancer and normal counterpart cells, including drug sensitivity testing, gene expression profiling and microRNA expression profiling have been completed. Data and tools for searching these data will be made publicly available through the NCI Developmental Therapeutics Program at http://SCLC.cancer.gov. SCLC is an aggressive, recalcitrant cancer and have seen limited treatment advances in the last 30 years. Drug sensitivity data coupled with the transcription and microRNA profiles of a cohort of SCLC cell lines may help define novel treatment paradigms.
Project description:The insulin-like growth factor 1 receptor (IGF-1R) plays crucial roles in developmental and cancer biology. Most of its biological effects have been ascribed to its tyrosine kinase activity. We report that IGF-1 promotes the modification of IGF-1R by small ubiquitin-like modifier protein-1 (SUMO-1) and its translocation to the nucleus. Nuclear IGF-1R associated with enhancer-like elements and increased transcription in reporter assays. We used ChIP-seq to examine the interaction of IGF-1R with DNA on a genome-wide scale. Analysis of the data set resulted in 568 candidate peaks, that is, statistically significant IGF-1R-enriched regions. The IGF-1R-enriched regions were divided into five classes on the basis of their location relative to known genes. Most of the IGF-1R-interacting sites (80%) were located distal from any annotated gene (intergenic), 6.3% were located in introns, 6.3% in exons, 3.4% were <20 kb upstream of an annotated transcript start site (5'UTR + 20 kb upstream), and 3.6% were <20 kb downstream of an annotated transcript end site (3'UTR + 20 kb downstream).