Seiji Kosaihira

Gefitinib (IRESSA) sensitive lung cancer cell lines show phosphorylation of Akt without ligand stimulation

BackgroundPhase III trials evaluating the efficacy of gefitinib (IRESSA) in non-small cell lung cancer (NSCLC) lend support to the need for improved patient selection in terms of gefitinib use. Mutation of the epidermal growth factor receptor (EGFR) gene is reported to be associated with clinical responsiveness to gefitinib. However, gefitinib-sensitive and prolonged stable-disease-defined tumors without EGFR gene mutation have also been reported.MethodsTo identify other key factors involved in gefitinib sensitivity, we analyzed the protein expression of molecules within the EGFR family, PI3K-Akt and Ras/MEK/Erk pathways and examined the sensitivity to gefitinib using the MTT cell proliferation assay in 23 lung cancer cell lines.ResultsWe identified one highly sensitive cell line (PC9), eight cell lines displaying intermediate-sensitivity, and 14 resistant cell lines. Only PC9 and PC14 (intermediate-sensitivity) displayed an EGFR gene mutation including amplification. Eight out of the nine cell lines showing sensitivity had Akt phosphorylation without ligand stimulation, while only three out of the 14 resistant lines displayed this characteristic (P = 0.0059). Furthermore, the ratio of phosphor-Akt/total Akt in sensitive cells was higher than that observed in resistant cells (P = 0.0016). Akt phosphorylation was partially inhibited by gefitinib in all sensitive cell lines.ConclusionThese results suggest that Akt phosphorylation without ligand stimulation may play a key signaling role in gefitinib sensitivity, especially intermediate-sensitivity. In addition, expression analyses of the EGFR family, EGFR gene mutation, and FISH (fluorescence in situ hybridization) analyses showed that the phosphorylated state of EGFR and Akt might be a useful clinical marker of Akt activation without ligand stimulation, in addition to EGFR gene mutation and amplification, particularly in adenocarcinomas.

Anticancer drug clustering in lung cancer based on gene expression profiles and sensitivity database

AbstractbackgroundThe effect of current therapies in improving the survival of lung cancer patients remains far from satisfactory. It is consequently desirable to find more appropriate therapeutic opportunities based on informed insights. A molecular pharmacological analysis was undertaken to design an improved chemotherapeutic strategy for advanced lung cancer.MethodsWe related the cytotoxic activity of each of commonly used anti-cancer agents (docetaxel, paclitaxel, gemcitabine, vinorelbine, 5-FU, SN38, cisplatin (CDDP), and carboplatin (CBDCA)) to corresponding expression pattern in each of the cell lines using a modified NCI program.ResultsWe performed gene expression analysis in lung cancer cell lines using cDNA filter and high-density oligonucleotide arrays. We also examined the sensitivity of these cell lines to these drugs via MTT assay. To obtain our reproducible gene-drug sensitivity correlation data, we separately analyzed two sets of lung cancer cell lines, namely 10 and 19. In our gene-drug correlation analyses, gemcitabine consistently belonged to an isolated cluster in a reproducible fashion. On the other hand, docetaxel, paclitaxel, 5-FU, SN-38, CBDCA and CDDP were gathered together into one large cluster.ConclusionThese results suggest that chemotherapy regimens including gemcitabine should be evaluated in second-line chemotherapy in cases where the first-line chemotherapy did not include this drug. Gene expression-drug sensitivity correlations, as provided by the NCI program, may yield improved therapeutic options for treatment of specific tumor types.

Activity of EGFR-tyrosine kinase and ALK inhibitors for EML4-ALK-rearranged non-small-cell lung cancer harbored coexisting EGFR mutation.

BackgroundThe EML4–ALK (echinoderm microtubule-associated protein-like 4 gene and the anaplastic lymphoma kinase gene) fusion oncogene represents a novel molecular target in a small subset of non–small–cell lung cancers (NSCLCs). The EML4–ALK fusion gene occurs generally in NSCLC without mutations in epidermal growth factor receptor (EGFR) and KRAS.Case presentationWe report that a case of EML4–ALK-positive NSCLC with EGFR mutation had a response of stable disease to both an EGFR tyrosine kinase inhibitor (EGFR-TKI) and ALK inhibitor.ConclusionsWe described the first clinical report of a patient with EML4–ALK-positive NSCLC with EGFR mutation that had a response of stable disease to both single-agent EGFR-TKI and ALK inhibitor. EML4–ALK translocation may be associated with resistance to EGFR-TKI, and EGFR signaling may contribute to resistance to ALK inhibitor in EML4–ALK-positive NSCLC.

The feasibility study of Carboplatin plus Etoposide for advanced small cell lung cancer with idiopathic interstitial pneumonias.

Background: Idiopathic interstitial pneumonias (IIPs) are among the most common complications in patients with lung cancer. In such patients with cancer, the most serious expression of toxicity in Japan is acute exacerbation of IIPs caused by anticancer treatment. Nevertheless, there has been no consensus and no evidence presented, regarding optimal treatment for advanced lung cancer with IIP. Patients and Methods: Chemotherapy-naive patients with advanced small cell lung cancer (SCLC) with IIP who were ineligible for curative radiotherapy were enrolled. Patients received carboplatin every 21 days at a dose of area under the curve 6.0 on day 1 and etoposide at a dose of 100 mg/m2 on days 1 to 3. Results: Between July 2002 and October 2008, 17 patients with SCLC with IIP, including 14 men, eight of whom were diagnosed with idiopathic pulmonary fibrosis, were enrolled and treated for a mean of 3.5 cycles of carboplatin plus etoposide. One patient (5.9%; 95% confidence interval, 0–18.4%) with clinically confirmed idiopathic pulmonary fibrosis had acute exacerbation of IIPs associated with the treatment. The overall response rate was 88.2%. The median progression-free survival, median survival time, and 1-year survival rate were 5.5 months, 8.7 months, and 29.4%, respectively. Conclusion: This is the first report indicating that patients with advanced SCLC with IIPs may benefit from chemotherapy. Patients with advanced SCLC with IIP treated with etoposide and carboplatin combination chemotherapy gain benefits, with safety equivalent to that seen in patients without IIP. The results from this study would support, on ethical grounds, the conduct of a large-scale study to evaluate this regimen.

Phase II study of nimustine hydrochloride (ACNU) plus paclitaxel for refractory small cell lung cancer.

PURPOSE Bi-weekly administrations of nimustine hydrochloride (ACNU) plus paclitaxel were evaluated in this phase II study in patients with refractory small cell lung cancer (SCLC). METHODS Patients who had disease progression within 3 months after treatment with irinotecan (CPT-11)-containing regimens were entered. They were treated with every other week administrations of ACNU 50 mg/m(2) plus paclitaxel 110 mg/m(2) on day 1 over 2 weeks. RESULTS Twenty-four patients (20 males and 4 females, median age of 64 years, 17 patients with Eastern Cooperative Oncology Group [ECOG] performance status [PS] 0-1 and 7 patients with PS 2) participated in the trial. Of the 24 refractory patients after CPT-11 containing regimens, 17 patients had been given etoposide plus platinum. There were six partial responses, and an overall response rate of 25% (95% confidence interval, 10-46%) was obtained. The median time to progression and the median survival time after enrollment into this study were 2.8 and 5.8 months, respectively. The median overall survival from the first-line treatment was 19.5 months. The major toxicity was myelosuppression. Grade 4 neutropenia occurred in 13% of patients, and Grade 4 thrombocytopenia was observed in 13% of patients. There was one treatment-related death, attributed to pneumonitis. CONCLUSION Bi-weekly administrations of ACNU plus paclitaxel provided a practical and well-tolerated regimen that was active for CPT-11-refractory SCLC.

Abstract 5548: High copy number of the MET gene predicts resistance to EGFR-TKI in non-small cell lung cancer patients.

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Background Non-small cell lung cancer (NSCLC) patients with EGFR gene mutations have shown a dramatic responses to EGFR tyrosine kinase inhibitor (EGFR-TKI). However, it is recognized that, clinically, drug resistance eventually emerges and this limits the mean duration of response. Although mechanisms of acquired resistance to EGFR-TKI, such as T790M secondary mutation and MET amplification, have recently been described, other mechanisms of resistant to EGFR-TKI should be identified to broaden the therapeutic strategy for NSCLC in patients with EGFR gene mutations. Patients and Methods We evaluated 26 lung tumor samples from NSCLC patients who had received EGFR-TKI treatment from 2009 to 2011 at Nippon Medical School Hospital. Status of copy numbers and amplification of the MET gene were examined by fluorescence in situ hybridization (FISH) and estimated by high throughout automated image analysis. Results High copy number (>4 copies/cell) was observed in 6 patients (27%) and amplification (MET/CEP7 ≥2.0) was seen in 0 of 26 NSCLC patients. MET gene copy number status was not correlated with EGFR gene mutation, gender, histology, or smoking history. In 2 of the 6 cases with high copy number, high copy numbers were found at both the pre- and post-treatment stages. Among the 6 patients with high copy number, 5 patients achieved partial response (PR) and one patient showed stable disease (SD) with EGFR-TKI therapy. However, the 6 patients with high copy number had statistically significantly shorter progression-free survival (PFS) than the 20 patients with low copy numbers. (p=0.048, log-rank test). The median PFS of patients with High copy number and low copy numbers was 9.5 months and 24.4 months, respectively. Conclusion Detection of high copy number of the MET gene by FISH may be useful for predicting response to EGFR-TKI. The correlation between MET gene copy number and response to EGFR-TKI should be further evaluated using larger sample sizes. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5548. doi:1538-7445.AM2012-5548