Actinin-4 protein overexpression as a predictive biomarker in adjuvant chemotherapy for resected lung adenocarcinoma

Aim: Although several clinical trials demonstrated the benefits of platinum-combination adjuvant chemotherapy for stage II–IIIA lung adenocarcinoma, predictive biomarkers for the efficacy of such therapy have not yet been identified. We evaluated protein overexpression of actinin-4 as a predictive biomarker of the efficacy of adjuvant chemotherapy in resected lung adenocarcinoma. Materials & methods: We measured actinin-4 protein levels in patients with completely resected stage II–IIIA lung adenocarcinoma using immunohistochemistry and then retrospectively compared survival between adjuvant chemotherapy and observation groups. Results: A total of 148 eligible patients were classified into actinin-4 positive or negative cases by immunohistochemistry. In the former, patients with adjuvant chemotherapy survived significantly longer than those with observation (hazard ratio [HR]: 0.307; p = 0.028). But, no significant survival benefit was noted with adjuvant chemotherapy (HR: 0.926; p = 0.876) in the latter. Conclusion: This marker could predict the efficacy of adjuvant chemotherapy for resected lung adenocarcinoma patients.

Phase II study of efficacy of bevacizumab plus chemotherapy in management of malignant pleural effusion (MPE) in non-squamous non-small cell lung cancer (NSCLC) patients with MPE unsuccessfully controlled by tube drainage or pleurodesis (North East Japan Study Group Trial NEJ-013B-2)

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Background: Prospective and retrospective studies on intrapleural therapy of malignant pleural effusion (MPE) have reported that the success rate for controlling pleural effusion was 50–70% at 2.5 months, and that the median post-pleurodesis survival time was 6-9 months. When pleurodesis is unsuccessful, and the lung is not fully expanded after drainage, the patients cannot receive effective chemotherapy. Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of MPE. Here, a multicenter phase II trial was conducted to evaluate bevacizumab therapy in non-squamous non-small cell lung carcinoma patients with unsuccessful management of MPE. Methods: Non-squamous NSCLC patients with MPE who had received unsuccessful tube drainage or pleurodesis received chemotherapy with bevacizumab (15 mg/kg) every 3 weeks. The primary endpoint was Pleural effusion control rate (PECR), defined as the percentage of patients without reaccumulation of MPE for 8 weeks. The secondary endpoint was pleural Progression-free survival (PPFS), defined as PFS without reaccumulation of MPE. Results: Fifteen of 20 patients entered received a median of 4 cycles of carboplatin plus paclitaxel or pemetrexed including maintenance therapy with bevacizumab. The PECR was 80% of treated patients (95% CI: 78-82%). PPFS was 16.6 months (95% CI: 11.46-21.80 months). The response rate (RR) and disease control rate (DCR) were 45% (95% CI: 39.6-50.4%), and 80% (95% CI: 78.0-82.0 %), respectively, and the median PFS and overall survival (OS) were 9.8 months (95% CI: 4.38-15.28 months) and 19.6 months (95% CI: 4.38-15.28 months), respectively. Toxicities of grade ≥3 included neutropenia (50.0%), thrombocytopenia (10.0%), proteinuria (10.0%), hypertension (2.0%), pulmonary embolism (5%). Conclusions: The combination of bevacizumab with chemotherapy demonstrated efficacy with acceptable toxicities in controlling MPE in patients with non-squamous NSCLC whose MPE was unsuccessfully controlled by tube drainage or pleurodesis.

Prognostic significance of ABCB1 in stage I lung adenocarcinoma

Cancer stem cell (CSC) properties have been recently proposed to explain tumor carcinogenesis and multidrug resistance in several human cancers, including non-small cell lung cancer (NSCLC). The present study examined the protein expression of three CSC-associated markers, namely ATP binding cassette subfamily B member 1 (ABCB1), aldehyde dehydrogenase 1 family member A1 (ALDH1A1) and cluster of differentiation (CD) 44, by immunohistochemistry in 194 NSCLC patients who underwent complete resection of NSCLC tumors. The association between the expression of these proteins and patient prognosis was evaluated to clarify the prognostic significance of CSC-associated markers in NSCLC patients. Positive staining for ABCB1 demonstrated a trend toward worse survival compared with negative staining in stage I-III NSCLC. Negative staining for ALDH1 or CD44 exhibited a trend toward worse survival compared with positive staining in stage I-III NSCLC. It was observed that patients with stage I lung adenocarcinoma (ADC) showing positivity for ABCB1 expression had significantly poorer survival than those with negative ABCB1 staining (P=0.03). Furthermore, stage I ADC patients with wild-type epidermal growth factor receptor (EGFR) who exhibited positive staining for ABCB1 had significantly shorter disease-free survival (DFS) compared with patients with negative staining for ABCB1 (P<0.01). Analyses by univariate and multivariate Cox proportional hazards models revealed that ABCB1-positive staining was significantly associated with DFS and was an independent prognostic factor (hazard ratio, 3.49; P<0.05) in these patients. These results suggest that ABCB1 protein expression is useful for predicting prognosis and selecting patients for post-operative therapy in stage I lung ADC patients, particularly those harboring wild-type EGFR.

A Two-Gene Prognostic Classifier for Early-Stage Lung Squamous Cell Carcinoma in Multiple Large-Scale and Geographically Diverse Cohorts

INTRODUCTION

There are no validated molecular methods that prospectively identify patients with surgically resected lung squamous cell carcinoma (SCC) at high risk for recurrence. By focusing on the expression of genes with known functions in development of lung SCC and prognosis, we sought to develop a robust prognostic classifier of early-stage lung SCC.

METHODS

The expression of 253 genes selected by literature search was evaluated in microarrays from 107 stage I/II tumors. Associations with survival were evaluated by Cox regression and Kaplan-Meier survival analyses in two independent cohorts of 121 and 91 patients with SCC, respectively. A classifier score based on multivariable Cox regression was derived and examined in six additional publicly available data sets of stage I/II lung SCC expression profiles (n = 358). The prognostic value of this classifier was evaluated in meta-analysis of patients with stage I/II (n = 479) and stage I (n = 326) lung SCC.

RESULTS

Dual specificity phosphatase 6 gene (DUSP6) and actinin alpha 4 gene (ACTN4) were associated with prognostic outcome in two independent patient cohorts. Their expression values were utilized to develop a classifier that identified patients with stage I/II lung SCC at high risk for recurrence (hazard ratio [HR] = 4.7, p = 0.018) or cancer-specific mortality (HR = 3.5, p = 0.016). This classifier also identified patients at high risk for recurrence (HR = 2.7, p = 0.008) or death (HR = 2.2, p = 0.001) in publicly available data sets of stage I/II and in meta-analysis of stage I patients.

CONCLUSIONS

We have established and validated a prognostic classifier to inform clinical management of patients with lung SCC after surgical resection.

Urinary Metabolite Risk Biomarkers of Lung Cancer: A Prospective Cohort Study

BACKGROUND

Lung cancer is a major health burden causing 160,000 and 1.6 million deaths annually in the United States and worldwide, respectively.

METHODS

While seeking to identify stable and reproducible biomarkers in noninvasively collected biofluids, we assessed whether previously identified metabolite urinary lung cancer biomarkers, creatine riboside (CR), N-acetylneuraminic acid (NANA), cortisol sulfate, and indeterminate metabolite 561+, were elevated in the urines of subjects prior to lung cancer diagnosis in a well-characterized prospective Southern Community Cohort Study (SCCS). Urine was examined from 178 patients and 351 nondiseased controls, confirming that one of four metabolites was associated with lung cancer risk in the overall case-control set, whereas two metabolites were associated with lung cancer risk in European-Americans.

RESULTS

OR of lung cancer associated with elevated CR levels, and adjusted for smoking and other potential confounders, was 2.0 [95% confidence interval (CI), 1.2-3.4; P= 0.01]. In European-Americans, both CR and NANA were significantly associated with lung cancer risk (OR = 5.3; 95% CI, 1.6-17.6; P= 0.006 and OR=3.5; 95% CI, 1.5-8.4; P= 0.004, respectively). However, race itself did not significantly modify the associations. ROC analysis showed that adding CR and NANA to a model containing previously established lung cancer risk factors led to a significantly improved classifier (P= 0.01). Increasing urinary levels of CR and NANA displayed a positive association with increasing tumor size, strengthening a previously established link to altered tumor metabolism.

CONCLUSION AND IMPACT

These replicated results provide evidence that identified urinary metabolite biomarkers have a potential utility as noninvasive, clinical screening tools for early diagnosis of lung cancer. Cancer Epidemiol Biomarkers Prev; 25(6); 978-86. ©2016 AACR.

miR-200/ZEB axis regulates sensitivity to nintedanib in non-small cell lung cancer cells

Nintedanib (BIBF1120) is a multi-targeted angiokinase inhibitor and has been evaluated in idiopathic pulmonary fibrosis and advanced non-small cell lung cancer (NSCLC) patients in clinical studies. In the present study, we evaluated the antitumor effects of nintedanib in 16 NSCLC cell lines and tried to identify microRNA (miRNA) associated with sensitivity to nintedanib. No correlations between FGFR, PDGFR and VEGFR family activation and sensitivity to nintedanib were found. The difference in miRNA expression profiles between 5 nintedanib-sensitive and 5 nintedanib-resistant cell lines was evaluated by miRNA array and quantitative RT-PCR analysis (qRT-PCR). Expression of miR-200b, miR-200a and miR-141 belonging to the miR-200 family which contributes to epithelial-mesenchymal transition (EMT), was significantly lower in 5 nintedanib-resistant than in 5 nintedanib-sensitive cell lines. We examined the protein expression of EMT markers in these 10 NSCLC cell lines. E-cadherin expression was lower, and vimentin and ZEB1 expression were higher in 5 nintedanib-resistant cell lines. PC-1 was the most sensitive of the NSCLC cell lines to nintedanib. We established nintedanib-resistant PC-1 cells (PC-1R) by the stepwise method. PC-1R cells also showed decreased expression of miR-200b, miR-141 and miR-429 and increased expression of ZEB1 and ZEB2. We confirmed that induction of miR-200b or miR-141 enhanced sensitivity to nintedanib in nintedanib-resistant A549 and PC1-R cells. In addition, we evaluated the response to gefitinib in combination with nintedanib after TGF-β1 exposure of A549 cells. Nintedanib was able to reverse TGF-β1-induced EMT and resistance to gefitinib caused by miR-200b and miR-141 upregulation and ZEB1 downregulation. These results suggested that the miR-200/ZEB axis might be predictive biomarkers for sensitivity to nintedanib in NSCLC cells. Furthermore, nintedanib combined with gefitinib might be a novel therapeutic strategy for NSCLC cells with EMT phenotype and resistance to gefitinib.

Inhibition of ABCB1 Overcomes Cancer Stem Cell-like Properties and Acquired Resistance to MET Inhibitors in Non-Small Cell Lung Cancer

Patients with non-small cell lung cancer (NSCLC) EGFR mutations have shown a dramatic response to EGFR inhibitors (EGFR-TKI). EGFR T790M mutation and MET amplification have been recognized as major mechanisms of acquired resistance to EGFR-TKI. Therefore, MET inhibitors have recently been used in NSCLC patients in clinical trials. In this study, we tried to identify the mechanism of acquired resistance to MET inhibitors. We analyzed the antitumor effects of two MET inhibitors, PHA-665752 and crizotinib, in 10 NSCLC cell lines. EBC-1 cells with MET amplification were the only cells that were sensitive to both MET inhibitors. We established PHA-665752-resistant EBC-1 cells, namely EBC-1R cells. Activation of KRAS, EGFR, and FGFR2 signaling was observed in EBC-1R cells by FISH and receptor tyrosine kinase phosphorylation antibody arrays. EBC-1R cells also showed overexpression of ATP-binding cassette subfamily B member 1 (ABCB1) as well as phosphorylation of MET. EBC-1R cells grew as cell spheres that exhibited cancer stem cell-like (CSC) properties and epithelial-mesenchymal transition (EMT). The level of miR-138 that targeted ABCB1 was decreased in EBC-1R cells. ABCB1 siRNA and the ABCB1 inhibitor elacridar could reduce sphere numbers and suppress EMT. Elacridar could also reverse resistance to PHA-665752 in EBC-1R cells. Our study demonstrated that ABCB1 overexpression, which was associated with CSC properties and EMT, was involved in the acquired resistance to MET inhibitors. Inhibition of ABCB1 might be a novel therapeutic strategy for NSCLC patients with acquired resistance to MET inhibitors.

Abstract 756: Inhibition of ABCB1 overcomes cancer stem cell-like properties and acquired resistance to MET inhibitor in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) patients with EGFR mutations have shown a dramatic response to EGFR inhibitors (EGFR-TKI). EGFR T790M mutation and MET amplification have been recognized as mechanisms of acquired resistance to EGFR-TKI. Recently, MET inhibitors have been used in NSCLC patients for clinical trials. In this study, we tried to identify the mechanisms of acquired resistant to MET inhibitor. We analyzed the antitumor effects of two MET inhibitors; PHA-665752 and crizotinib, in 10 NSCLC cell lines. EBC1 cells with MET amplification were only sensitive cells to both of MET inhibitors. We have established PHA-665752 resistant cells; namely EBC1-R cells. EBC1-R cells showed high expression levels of ATP-binding Cassette Sub-family B Member 1 (ABCB1) as wells as phosphorylation MET (p-MET). EBC1-R cells grew as cell sphere that exhibited cancer stem cell-like (CSC) properties and epithelial mesenchymal transition (EMT) feature. Two miRNAs, miR-374a and miR-138 which targeted ABCB1, were decreased in EBC1-R cells. ABCB1 inhibitor elacridar could suppress sphere numbers and EMT phenomenon and restore to the resistance to PHA-665752 in EBC1-R cells. Our study demonstrated that ABCB1 overexpression associated with CSC properties and EMT may be critical for acquire resistance for MET inhibitor. ABCB1 inhibition might be a novel therapeutic strategy for resistance to MET inhibitor in NSCLC cells.

Citation Format: Teppei Sugano, Masahiro Seike, Rintaro Noro, Chie Soeno, Shinji Nakamichi, Nobuhiko Nishijima, Masaru Matsumoto, Susumu Takeuchi, Akihiko Miyanaga, Kaoru Kubota, Akihiko Gemma. Inhibition of ABCB1 overcomes cancer stem cell-like properties and acquired resistance to MET inhibitor in non-small cell lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 756. doi:10.1158/1538-7445.AM2015-756

Abstract 184: miR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rapidly fatal malignancy that is increasing in incidence in Japan. In this study, we performed gene and microRNA (miRNA) expres¬sion profiling to identify novel therapeutic targets in MPM cells. Based on relative sensitivities to pemetrexed (PEM) and the histone deacetylase (HDAC) inhibitor, vorinostat (SAHA), 211H cells were determined to be the only sensitive MPM cell line out of the 6 tested. On the same series of cell lines, we performed whole genome transcriptomic profiling via DNA microarrays and pathway analysis of the derived data. Of particular note, IL-18 gene expression levels were signifi¬cantly higher in the cell lines that were either drug resistant or displayed intermediate sensitivity, compared to the sensitive 211H cell line. Pathway analysis revealed IL-18 as an impor¬tant gene associated with drug sensitivity of MPM cells. A relationship between IL-18 overexpression and drug resistance was also observed following targeted assessment of 10 cyto¬kine genes using quantitative RT-PCR. miRNA expression profiles were evaluated in the MPM cell line panel in order to discern the mechanism of IL-18 induction in the drug-resistant lines. We found that miR-379 and miR-411 belonged to the same cluster of miRNAs located on chromosome 14q32 that commonly target the IL-18 gene. Luciferase reporter assays revealed that miR-379 and miR-411 directly target the IL-18 gene. Introduction of miR-379 plus miR-411, as well as IL-18 silencing, significantly suppressed the invasive capacity of MESO1 cells in vitro. Furthermore, the use of either PEM or SAHA together with miR-379 plus miR-411 mimics mediated increased sensitivity to these drugs in MESO1 cells. These results suggest that the miR-379/411 cluster may provide new therapeutic opportunities for advanced MPM patients, depending on the nature of IL-18 gene expression.

Citation Format: Akihiko Miyanaga, Masahiro Seike, Kazuo Yamamoto, Susumu Takeuchi, Rintaro Noro, Yuji Minegishi, Kaoru Kubota, Akihiko Gemma. miR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 184. doi:10.1158/1538-7445.AM2015-184

Effective Crizotinib schedule for an elderly patient with ALK rearranged non-small-cell lung cancer: a case report

Background

Non-small-cell lung cancers (NSCLCs) harboring translocations in anaplastic lymphoma kinase (ALK) are highly sensitive to small-molecule ALK kinase inhibitors, such as crizotinib.

Case presentation

We describe a case of post-operative local recurrence of lung adenocarcinoma in an 81 year-old male. He underwent radiation and received chemotherapy with docetaxel, but neither treatment regimen was effective. Following identification of ALK rearrangements, crizotinib treatment was initiated. After treatment with crizotinib for 5 days, adverse events including acute renal failure (grade 2/CTCAE ver4.0) and congestive heart failure (grade 3) occurred. Crizotinib modified treatment was required. Half dose of crizotinib treatment could not control tumor progression. Ultimately, crizotinib was administrated at a dose of 250 mg twice daily every 3 day dosing for 13 months with maintenance of the anti-tumor effect.

Conclusion

This is the first case report that skip schedule was more effective than dose reduction daily in crizotinib administration for ALK rearranged NSCLC patient with severe adverse events.

Control of the MYC-eIF4E axis plus mTOR inhibitor treatment in small cell lung cancer

Background

Mammalian target of rapamycin (mTOR) inhibitors have anti-tumor effects against renal cell carcinoma, pancreatic neuroendocrine cancer and breast cancer. In this study, we analyzed the antitumor effects of mTOR inhibitors in small cell lung cancer (SCLC) cells and sought to clarify the mechanism of resistance to mTOR inhibitors.

Methods

We analyzed the antitumor effects of three mTOR inhibitors including everolimus in 7 SCLC cell lines by MTS assay. Gene-chip analysis, receptor tyrosine kinases (RTK) array and Western blotting analysis were performed to identify molecules associated with resistance to everolimus.

Results

Only SBC5 cells showed sensitivity to everolimus by MTS assay. We established two everolimus resistant-SBC5 cell lines (SBC5 R1 and SBC5 R10) by continuous exposure to increasing concentrations of everolimus stepwise. SPP1 and MYC were overexpressed in both SBC5 R1 and SBC5 R10 by gene-chip analysis. High expression levels of eukaryotic translation initiation factor 4E (eIF4E) were observed in 5 everolimus-resistant SCLC cells and SBC5 R10 cells by Western blotting. MYC siRNA reduced eIF4E phosphorylation in SBC5 cells, suggesting that MYC directly activates eIF4E by an mTOR-independent bypass pathway. Importantly, after reduction of MYC or eIF4E by siRNAs, the SBC5 parent and two SBC5-resistant cells displayed increased sensitivity to everolimus relative to the siRNA controls.

Conclusion

These findings suggest that eIF4E has been shown to be an important factor in the resistance to everolimus in SCLC cells. Furthermore, a link between MYC and mTOR-independent eIF4E contribute to the resistance to everolimus in SCLC cells. Control of the MYC-eIF4E axis may be a novel therapeutic strategy for everolimus action in SCLC.

MET FISH-positive status predicts short progression-free survival and overall survival after gefitinib treatment in lung adenocarcinoma with EGFR mutation

BACKGROUND

Lung adenocarcinoma patients with EGFR gene mutations have shown a dramatic response to gefitinib. However, drug resistance eventually emerges which limits the mean duration of response. With that in view, we examined the correlations between MET gene status as assessed by fluorescence in situ hybridization (FISH) with overall survival (OS) and progression-free survival (PFS) in adenocarcinoma patients with EGFR gene mutations who had received gefitinib therapy.

METHODS

We evaluated 35 lung cancer samples with EGFR mutation from adenocarcinoma patients who had received gefitinib. Gene copy numbers (GCNs) and amplification of MET gene before gefitinib therapy was examined by FISH. MET protein expression was also evaluated by immunohistochemistry (IHC).

RESULTS

FISH assessment showed that of the 35 adenocarcinoma samples, 10 patients (29%) exhibited high polysomy (5 copies≦mean MET per cell) and 1 patient (3%) exhibited amplification (2≦MET gene (red)/CEP7q (green) per cell). IHC evaluation of MET protein expression could not confirm MET high polysomy status. The Eleven patients with MET FISH positivity had significantly shorter progression-free survival (PFS) and overall survival (OS) than the 24 patients who were MET FISH-negative (PFS: p = 0.001 and OS: p = 0.03). Median PFS and OS with MET FISH-positivity were 7.6 months and 16.8 months, respectively, whereas PFS and OS with MET FISH-negativity were 15.9 months and 33.0 months, respectively. Univariate analysis revealed that MET FISH-positivity was the most significant independent factor associated with a high risk of progression and death (hazard ratio, 3.83 (p = 0.0008) and 2.25 (p = 0.03), respectively).

CONCLUSIONS

Using FISH analysis to detect high polysomy and amplification of MET gene may be useful in predicting shortened PFS and OS after Gefitinib treatment in lung adenocarcinoma. The correlation between MET gene status and clinical outcomes for EGFR-TKI should be further evaluated using large scale samples.

Prognostic significance of PIK3CA and SOX2 in Asian patients with lung squamous cell carcinoma

The recent development of human genome studies has demonstrated the possibility of alteration of several genes as oncogenic driver mutations of lung squamous cell carcinoma (SQCC). FGFR1, PIK3CA and SOX2 genes have been recognized as candidate driver genes of SQCC. The aim of the present study was to evaluate FGFR1, PIK3CA and SOX2 protein expression in SQCC and determine whether the expression of these can be used as prognostic biomarkers. We evaluated the relationships between FGFR1, PIK3CA and SOX2 expression by immunohistochemical analysis and overall survival in lung SQCC patients with stage I-III that originated from China, United States and Japan. FGFR1-positive, PIK3CA-negative and SOX2-positive staining each showed trends toward better survival, although the differences were not statistically significant in a Chinese cohort of 57 patients. Patients with PIK3CA-negative and SOX2-positive staining (PIK3CA(-)/SOX2(+)) showed better prognosis compared with those with PIK3CA-positive or SOX2-negative staining in the Chinese cohort (p=0.04). The robustness of PIK3CA(-)/SOX2(+) classification as having prognostic significance was validated in an independent set of 66 Japanese cohort patients (p=0.007). Japanese SQCC patients with stage I were evaluated separately and PIK3CA(-)/SOX2(+) cases had significantly better survival than the group with PIK3CA-positive or SOX2-negative status (p=0.03). In univariate and multivariable Cox proportional hazards models of Asian stage I patients, the PIK3CA(-)/SOX2(+) classification was statistically significantly associated with survival and was an independent prognostic factor. Classification by PIK3CA and SOX2 protein expression is useful for predicting the prognosis of Asian patients with lung SQCC with stage I.

Abstract 784: Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed

Background: Pemetrexed (PEM) is currently recommended as one of the standard anticancer drugs for malignant pleural mesothelioma (MPM). However, the mechanism of the sensitivity of MPM to PEM remains unclear.

Materials and Methods: We analyzed the antitumor effects of PEM in six MPM cell lines by MTS assay. To identify genes associated with drug sensitivity, we conducted gene expression profiling on the same set of cell lines using GeneChips and pathway analysis.

Results: Three cell lines were sensitive to PEM. Eighteen transcripts and fourteen genes identified by Gene-chips were significantly correlated with sensitivity to PEM. Pathway analysis revealed that osteopontin (SPP1/OPN) was an important target in PEM sensitivity. Overexpression of SPP1/OPN was observed in the sensitive cells by quantitative RT-PCR analysis and Western blotting. Introduction of SPP1/OPN by lentiviral vector significantly enhanced the invasion activities of MPM cells. PEM treatment with SPP1/OPN knockdown inhibited the PEM-induced cell growth-inhibitory effect in PEM-sensitive cells. Expression of SPP1/OPN and AKT phosphorylation significantly decreased after PEM treatment of the PEM sensitive cells. High immunohistochemical expression of SPP1/OPN was observed in two of three MPM patients who had a partial response to PEM-based chemotherapy.

Conclusion: PEM has anti-tumor effects in MPM cells dependent on SPP1/OPN overexpression resulting in AKT activation. Our results suggest that SPP1 may be used as a single predictive biomarker of the effectiveness of PEM treatment in MPM.

Citation Format: Susumu Takeuchi, Masahiro Seike, Rintaro Noro, Chie Soeno, Teppei Sugano, Fenfei Zou, Masaru Matsumoto, Akihiko Miyanaga, Yuji Minegishi, Kaoru Kubota, Akihiko Gemma. Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 784. doi:10.1158/1538-7445.AM2014-784

MiR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rapidly fatal malignancy that is increasing in incidence in Japan. In this study, we performed gene and microRNA (miRNA) expression profiling to identify novel therapeutic targets in MPM cells. Based on relative sensitivities to pemetrexed (PEM) and the histone deacetylase (HDAC) inhibitor, vorinostat (SAHA), 211H cells were determined to be the only sensitive MPM cell line out of the 6 tested. On the same series of cell lines, we performed whole genome transcriptomic profiling via DNA microarrays and pathway analysis of the derived data. Of particular note, IL-18 gene expression levels were significantly higher in the cell lines that were either drug resistant or displayed intermediate sensitivity, compared to the sensitive 211H cell line. Pathway analysis revealed IL-18 as an important gene associated with drug sensitivity of MPM cells. A relationship between IL-18 overexpression and drug resistance was also observed following targeted assessment of 10 cytokine genes using quantitative RT-PCR. miRNA expression profiles were evaluated in the MPM cell line panel in order to discern the mechanism of IL-18 induction in the drug-resistant lines. We found that miR-379 and miR-411 belonged to the same cluster of miRNAs located on chromosome 14q32 that commonly target the IL-18 gene. Luciferase reporter assays revealed that miR-379 and miR-411 directly target the IL-18 gene. Introduction of miR-379 plus miR-411, as well as IL-18 silencing, significantly suppressed the invasive capacity of MESO1 cells in vitro. Furthermore, the use of either PEM or SAHA together with miR-379 plus miR-411 mimics mediated increased sensitivity to these drugs in MESO1 cells. These results suggest that the miR-379/411 cluster may provide new therapeutic opportunities for advanced MPM patients, depending on the nature of IL-18 gene expression.

Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed

Pemetrexed (PEM) is currently recommended as one of the standard anticancer drugs for malignant pleural mesothelioma (MPM). However, the mechanism of the sensitivity of MPM to PEM remains unclear. We analyzed the antitumor effects of PEM in six MPM cell lines by MTS assay. To identify genes associated with drug sensitivity, we conducted gene expression profiling on the same set of cell lines using GeneChips and pathway analysis. Three cell lines were sensitive to PEM. A total fo 18 transcripts and 14 genes identified by GeneChips were significantly correlated with sensitivity to PEM. Pathway analysis revealed that osteopontin (SPP1/OPN) was an important target in PEM sensitivity. Overexpression of SPP1/OPN was observed in the sensitive cells by quantitative PCR and western blot analysis. Introduction of SPP1/OPN by lentiviral vector significantly enhanced the invasion activities of MPM cells. PEM treatment with SPP1/OPN knockdown inhibited the PEM-induced cell growth-inhibitory effect in PEM-sensitive cells. Expression of SPP1/OPN and AKT phosphorylation significantly decreased after PEM treatment of the PEM-sensitive cells. High immunohistochemical expression of SPP1/OPN was observed in two of three MPM patients who had a partial response to PEM-based chemotherapy. PEM has antitumor effects in MPM cells dependent on SPP1/OPN overexpression resulting in AKT activation. Our results suggest that SPP1 may be used as a single predictive biomarker of the effectiveness of PEM treatment in MPM.

MiR-134/487b/655 cluster regulates TGF-β-induced epithelial-mesenchymal transition and drug resistance to gefitinib by targeting MAGI2 in lung adenocarcinoma cells

Epithelial-mesenchymal transition (EMT) has recently been recognized as a key element of cell invasion, migration, metastasis, and drug resistance in several types of cancer, including non-small cell lung cancer (NSCLC). Our aim was to clarify microRNA (miRNA)-related mechanisms underlying EMT followed by acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) in NSCLC. miRNA expression profiles were examined before and after transforming growth factor β1 (TGF-β1) exposure in four human adenocarcinoma cell lines with or without EMT. Correlation between expressions of EMT-related miRNAs and resistance to EGFR-TKI gefitinib was evaluated. miRNA array and real-time quantitative reverse transcription PCR (qRT-PCR) revealed that TGF-β1 significantly induced overexpression of miR-134, miR-487b, and miR-655, which belong to the same cluster located on chromosome 14q32, in lung adenocarcinoma cells with EMT. MAGI2 (membrane-associated guanylate kinase, WW, and PDZ domain-containing protein 2), a predicted target of these miRNAs and a scaffold protein required for PTEN, was diminished in A549 cells with EMT after the TGF-β1 stimulation. Overexpression of miR-134 and miR-487b promoted the EMT phenomenon and affected the drug resistance to gefitinib, whereas knockdown of these miRNAs inhibited the EMT process and reversed TGF-β1-induced resistance to gefitinib. Our study demonstrated that the miR-134/487b/655 cluster contributed to the TGF-β1-induced EMT phenomenon and affected the resistance to gefitinib by directly targeting MAGI2, in which suppression subsequently caused loss of PTEN stability in lung cancer cells. The miR-134/miR-487b/miR-655 cluster may be a new therapeutic target in patients with advanced lung adenocarcinoma, depending on the EMT phenomenon.

Distinct outcome of stage I lung adenocarcinoma with ACTN4 cell motility gene amplification

BACKGROUND

Even if detected at an early stage, a substantial number of lung cancers relapse after curative surgery. However, no method for distinguishing such tumors has yet been established.

PATIENTS AND METHODS

The copy number of the actinin-4 (ACTN4) gene was determined by fluorescence in situ hybridization on tissue microarrays comprising 543 surgically resected adenocarcinomas of the lung.

RESULTS

Amplification (an increase in the copy number by ≥ 2.0 fold) of the ACTN4 gene was detected in two of seven lung adenocarcinoma cell lines and 79 (15%) of 543 cases of pathological stage I-IV lung adenocarcinoma. Multivariate analysis revealed that ACTN4 gene amplification was the most significant independent factor associated with an extremely high risk of death (hazard ratio, 6.78; P = 9.48 × 10(-5), Cox regression analysis) among 290 patients with stage I lung adenocarcinoma. The prognostic significance of ACTN gene amplification was further validated in three independent cohorts totaling 1033 patients.

CONCLUSIONS

Amplification of the ACTN4 gene defines a small but substantial subset of patients with stage I lung adenocarcinoma showing a distinct outcome. Such patients require intensive medical attention and might benefit from postoperative adjuvant chemotherapy.

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

Background

The 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 presentation

We 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.

Conclusions

We 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.

Abstract 3541: Significance of osteopontin in the sensitivity of malignant pleural mesothelioma cells to pemetrexed

Introduction: Malignant pleural mesothelioma (MPM) is one of the fatal cancers associated with asbestos exposure.Pemetrexed (PEM) is currently recommended as one of the antitumor drugs consisted of standard therapies for MPM.However, the mechanism of the sensitivity of MPM to PEM remains unclear. Methods: We analyzed the antitumor effects of PEM in six MPM cell lines by MTS assay. To identify genes associated with drug sensitivity,we conducted gene expression profiling on the same set of cell lines using Affymetrix HG-U133A GeneChips. Pathway analysis was performed to provide a viewpoint of the biological function of the genes. Results: Three cell lines were sensitive to PEM. Eighteen transcripts and fourteen genes identified by Gene-chips were significantly correlated with sensitivity to PEM. Pathway analysis revealed that SPP1/OPN was an important target in PEM sensitivity. Overexpression of SPP1 was observed in the sensitive cells by Western blotting. Introduction of SPP1 by lentiviral vector significantly enhanced the invasion activities of MPM cells. Expression of SPP1/OPN and AKT phosphorylation were significantly decreased after PEM treatment of the PEM-sensitive cells. PEM treatment with SPP1/OPN knockdown inhibited the PEM-induced cell growth inhibitory effect in PEM-sensitive cells. Conclusions: Our results suggest that SPP1 may be used as a single predictive biomarker of the effectiveness of PEM treatment in MPM. Patient selection based on SPP1/OPN expression may be useful for future clinical development of PEM therapy for MPM.

Citation Format: Masahiro Seike, Susumu Takeuchi, Chie Soeno, Rintaro Noro, Yuji Minegishi, Akihiko Gemma. Significance of osteopontin in the sensitivity of malignant pleural mesothelioma cells to pemetrexed. [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 3541. doi:10.1158/1538-7445.AM2013-3541

Alternating chemotherapy with amrubicin plus cisplatin and weekly administration of irinotecan plus cisplatin for extensive-stage small cell lung cancer

BACKGROUND

A phase II study was conducted in order to determine the tumor efficacy and tolerance of alternating chemotherapy for extensive-stage small cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

Twenty patients with previously-untreated ED-SCLC were enrolled in the study. At least four courses of chemotherapy consisting of alternation of two drug combinations were given: alternating cycles of amrubicin and cisplatin with weekly administration of irinotecan and cisplatin at 3- or 4-week intervals.

RESULTS

The overall response rate was 85.0% (17/20). The median duration of overall survival and progression-free survival were 359 days and 227 days, respectively. Hematological toxicity was the main adverse event. Grade 3 or 4 neutropenia, thrombocytopenia and anemia were observed in 20 (100%), 4 (20%) and 6 (30%) patients, respectively. With regard to non-hematological adverse events, grade 3 or 4 anorexia, diarrhea, febrile neutropenia and infection were observed in 5 (25%), 2 (10%), 2 (10%) and 2 (10%) patients, respectively. No treatment-related death occurred during either regimen.

CONCLUSION

The novel alternating non-cross-resistant chemotherapy was probably active against ED-SCLC and had acceptable toxicities. Further evaluation of this treatment for ED-SCLC in randomized phase III trials is warranted.

Successful treatment of histiocytic sarcoma and concurrent HIV infection using a combination of CHOP and antiretroviral therapy

Histiocytic sarcoma (HS) is a rare malignancy of soft tissues with an unknown etiology. The CHOP (cyclophosphamide, vincristine sulfate, doxorubicin hydrochloride and prednisolone) regimen is often adopted as first-line chemotherapy; however, its therapeutic efficacy against HS is usually low. We herein first present the case of a patient with HS who was infected with human immunodeficiency virus-1 (HIV) in whom treatment with a combination of CHOP and antiretroviral therapy (ART) was successful. The patient has been in complete remission for 12 months following the discontinuation of chemotherapy under continuous ART. This case report may help to promote further investigation of both HS and HIV-related malignancy.

Combination chemotherapy of alternating etoposide and carboplatin with weekly administration of irinotecan and cisplatin in extensive-stage small-cell lung cancer

BACKGROUND

A phase II study was conducted to determine the tumor efficacy and tolerance of alternating chemotherapy in extensive-stage small-cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

Thirty-six patients with previously untreated ED-SCLC were enrolled in the study. At least four courses of chemotherapy consisting of alternation of two drug combinations were given: alternating cycles of etoposide and carboplatin (EC) with weekly administration of irinotecan and cisplatin (IP) at 3- or 4-week intervals.

RESULTS

The overall response rate was 81.8%. The median duration of survival and progression-free survival were 314 days and 144 days, respectively. Hematological toxicity was the main adverse event. Grade 3 or 4 neutropenia, thrombocytopenia and anemia were observed in 69.2, 25.6 and 23.1% of the patients, respectively. Severe diarrhea (10.8%) was remarkable during the IP regimen.

CONCLUSION

This novel alternating chemotherapy for patients with ED-SCLC showed moderate tumor efficacy and an acceptable safety profile.

MiR-23a regulates TGF-β-induced epithelial-mesenchymal transition by targeting E-cadherin in lung cancer cells

Transforming growth factor-β (TGF-β)-induced epithelial-mesenchymal transition (EMT) has been shown to be related to the pathogenesis of various diseases including lung cancer. Recently, microRNAs (miRNA) have been recognized as a new class of genes involved in human tumorigenesis. MiR-23a/24/27a is a miRNA cluster located in chromosome 19p13.12, which can function as an oncogene in several human cancers. In this study, we analyzed miR-23a/24/27a expression in 10 non-small cell cancer (NSCLC) cell lines by real-time PCR analysis. Correlation between expression of these miRNAs and TGF-β/Smad signaling was evaluated. We found that miR-23a could be regulated by TGF-β1 in a Smad-dependent manner in A549 lung adenocarcinoma cells showing the EMT phenomenon. Knockdown of miR-23a partially restored E-cadherin expression under conditions of TGF-β1 stimulation. In contrast, overexpression of miR-23a could suppress E-cadherin expression and stimulate EMT. Furthermore, A549 cells with overexpressed miR-23a were more resistant to gefitinib compared to the parental cells. These findings suggest that miR-23a regulates TGF-β-induced EMT by targeting E-cadherin in lung cancer cells and may be useful as a new therapeutic target in NSCLC.

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

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 (&gt;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

Enzastaurin has anti-tumour effects in lung cancers with overexpressed JAK pathway molecules

BACKGROUND

Enzastaurin, an oral serine-threonine kinase inhibitor, was initially developed as an ATP-competitive selective inhibitor against protein kinase Cβ. However, the mechanism by which enzastaurin contributes to tumourigenesis remains unclear.

METHODS

We analysed the anti-tumour effects of enzastaurin in 22 lung cancer cell lines to ascertain the potential for enzastaurin-based treatment of lung cancer. To identify molecules or signalling pathways associated with this sensitivity, we conducted a gene, receptor tyrosine kinases phosphorylation and microRNA expression profiling study on the same set of cell lines.

RESULTS

We identified eight genes by pathway analysis of molecules having gene-drug sensitivity correlation, and used them to build a support vector machine algorithm model by which sensitive cell lines were distinguished from resistant cell lines. Pathway analysis revealed that the JAK/STAT signalling pathway was one of the main ones involved in sensitivity to enzastaurin. Overexpression of JAK1 was observed in the sensitive cells by western blotting. Simultaneous administration of enzastaurin and JAK inhibitor inhibited enzastaurin-induced cell growth-inhibitory effect. Furthermore, lentiviral-mediated JAK1-overexpressing cells were more sensitive to enzastaurin than control cells.

CONCLUSION

Our results suggested that the JAK1 pathway may be used as a single predictive biomarker for enzastaurin treatment. The anti-tumour effect of enzastaurin should be evaluated in lung cancer with overexpressed JAK pathway molecules.

Randomized phase II study of two schedules of carboplatin and gemcitabine for stage IIIB and IV advanced non-small cell lung cancer (JACCRO LC-01 study)

BACKGROUND

Gemcitabine combined with carboplatin (CG) is one of the regimens used widely for advanced non-small cell lung cancer. Improvement in its toxicity may result in good clinical outcomes.

METHODS

A new schedule of gemcitabine and carboplatin (CG8) was compared with the standard one (CG1). Both are 3-weekly regimens, but carboplatin is administered on day 1 in CG1 and on day 8 in CG8.

RESULTS

The response rate of CG1 was 29.2%, which was higher than that of CG8 (22.2%). Median survival times in CG1 and CG8 were 348 and 455.5 days, respectively. Grade ≥3 leukopenia, thrombocytopenia and anemia were observed in 56.0, 72.0 and 36.0% of patients with CG1 and in 33.3, 25.9 and 14.8% of patients with CG8, respectively. Whereas grade ≥3 elevation of asparatate aminotransferase, alanine aminotransferase and alkaline phosphatase was seen mainly in CG8, grade ≥3 non-hematologic toxicities such as febrile neutropenia, infection, appetite loss, diarrhea and eruption were observed only in CG1.

CONCLUSION

CG1 is superior in response rate, but CG8 shows improved toxicities and a tendency of prolonged survival.

HSP27 modulates epithelial to mesenchymal transition of lung cancer cells in a Smad-independent manner

Epithelial to mesenchymal transition (EMT) is induced by transforming growth factor-β1 (TGF-β1) and is a crucial event for cancer cells to acquire invasive and metastatic phenotypes. However, the signals that induce EMT in cancer cells have yet to be adequately defined. In this study, a proteomic investigation was performed to understand the signaling pathway of the EMT of lung cancer using two-dimensional difference gel electrophoresis (2D-DIGE) and mass spectrometry. The protein expression profiles of A549 were compared to those of A549 cells treated with TGF-β1. Of more than 2,000 protein spots shown by 2D-DIGE, 53 were found to be up- or down-regulated upon induction with TGF-β1. In the 53 protein spots, the protein level of heat shock protein (HSP) 27 was found to increase significantly. HSP27 protein was higher in two different lung cancer cell lines, demonstrating the EMT phenomenon with TGF-β1. Notably, the silencing of HSP27 enhanced spindle integration, resulting in an additive effect with TGF-β1-induced EMT. Furthermore, the TGF-β1-induced HSP27 increase was not affected by the suppression of Smad2 and Smad3 in A549 cells. These results suggest that HSP27 was involved in TGF-β1-induced EMT in a Smad-independent manner in lung cancer cells and may provide an effective clinical strategy in lung cancer patients whose tumors are dependent on TGF-β1-induced EMT.

Histone deacetylase inhibitor enhances sensitivity of non-small-cell lung cancer cells to 5-FU/S-1 via down-regulation of thymidylate synthase expression and up-regulation of p21(waf1/cip1) expression

It is desirable to find more appropriate therapeutic opportunities in non-small-cell lung cancer (NSCLC) due to the current poor prognosis of affected patients. Recently, several histone deacetylase (HDAC) inhibitors, including suberoylanilide hydroxamic acid (SAHA), have been reported to exhibit antitumor activities against NSCLC. S-1, a novel oral fluorouracil anticancer drug, has been developed for clinical use in the treatment of NSCLC in Japan. Using an MTT assay, we analyzed the growth-inhibitory effect of 5-fluorouracil (5-FU), S-1, and SAHA against three NSCLC cell lines, as well as the breast cancer cell line MCF7 which is known to be highly sensitive to 5-FU. Combined treatment with low-dose SAHA enhanced 5-FU- and S-1-mediated cytotoxicity and resulted in synergistic effects, especially in 5-FU-resistant cells. Both the mRNA and protein expression levels of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and orotate phosphoribosyltransferase (OPRT), which are associated with 5-FU sensitivity/response, were analyzed in the cells undergoing treatment. 5-Fluorouracil-resistant lung cancer cells displayed high expression of TS mRNA and protein. Suberoylanilide hydroxamic acid down-regulated TS mRNA and protein expression, as well as repressed the rapid induction of this factor during 5-FU treatment, in all examined cell types. We also examined the status of the Rb-E2F1 pathway, with SAHA up-regulating p21(waf1/cip1) expression via promoter histone acetylation; this, in turn, blocked the Rb-E2F1 pathway. We conclude that combination therapy with SAHA and S-1 in lung cancer may be promising due to its potential to overcome S-1 resistance via modulation of 5-FU/S-1 sensitivity-associated biomarker (TS) by HDAC inhibitor.

Anticancer drug clustering based on proteomic profiles and a sensitivity database in a lung cancer cell line panel

Previously, we performed a molecular pharmacological study that applied a combination of DNA microarray-based gene expression profiling and drug sensitivity tests in vitro with a view to designing an improved chemotherapeutic strategy for advanced lung cancer. Utilizing recent key technological advances in proteomics, particularly antibody array-based methodologies, the current study aimed to examine the benefit of protein expression profiling in an analogous molecular pharmacological context. We performed protein expression analysis in a panel of lung cancer cell lines via an antibody array approach. Using a modified NCI program, we related cell line-specific proteomic profiles to the previously determined cytotoxic activity of a selection of commonly used anticancer agents, namely docetaxel, paclitaxel, gemcitabine, vinorelbine, 5-fluorouracil (5-FU), SN38, cisplatin (CDDP) and carboplatin (CBDCA). In addition, we compared these results with those obtained from our prior DNA microarray-based transcriptomic study. In our expression-drug correlation analysis using antibody array, gemcitabine consistently belonged to an isolated cluster. Docetaxel, paclitaxel, 5-FU, SN38, CBDCA and CDDP were gathered together into one large cluster. These results coincided with those generated by the prior transcriptomic study. Various genes were commonly listed that differentiated gemcitabine from the others. The identified factors associated with drug sensitivities were different between both analyses. Our proteomic profiling data provided confirmation of the previous transcript expression-drug sensitivity correlation analysis. These results suggest that chemotherapy regimens that include gemcitabine should be evaluated in second-line chemotherapy in cases where the first-line chemotherapy did not include this drug. Protein expression-drug sensitivity correlations in lung cancer cells in vitro may provide useful information in determining the most appropriate therapeutic options for lung cancer patients.

Exacerbation of idiopathic interstitial pneumonias associated with lung cancer therapy

OBJECTIVE AND METHODS

Idiopathic interstitial pneumonias (IIPs) frequently occur in association with lung cancer. However, there is no consensus on the best treatment of acute exacerbation of IIP in lung cancer patients (LC with IIP), including those with iatrogenic acute lung injury resulting from cancer treatments. We aimed to identify an appropriate strategy for treatment of this condition. We analyzed clinical features of 120 LC with IIP, retrospectively.

RESULTS

The incidence of acute exacerbation related to anticancer treatment was 22.7%; when the incidence was examined separately for patients receiving chemotherapy or the best supportive care, the incidence was 20.0% and 31.3%, respectively. Additional investigations should be directed to finding suitable regimens for treatment of LC with IIP and the selection of appropriate patients with LC with IIP for chemotherapy. The incidence of acute exacerbation caused by combination regimens of carboplatin + paclitaxel or a platinum agent + etoposide was significantly lower than that of other regimens (0% vs. 18%, respectively; p=0.025, Fisher's Exact Test). Patients with high levels of C-reactive protein before chemotherapy had a significantly higher risk of developing acute exacerbation (odds ratio 5.60, p=0.028).

CONCLUSION

There was no evidence that anticancer treatment, including chemotherapy, should be avoided in LC with IIP. To establish an appropriate cancer treatment for LC with IIP, a prospective clinical study should be performed to evaluate various treatment modalities in a larger patient population.

[EGFR and gefitinib (Iressa)]

We summarized the relationship between EGFR gene polymorphisms/mutations and gefitinib(Iressa). The SNPs of CA-simple sequence repeat of EGFR intron 1 and promoter sequence were reported to be related to the sensitivity and/ or toxicity of gefitinib(Iressa). Many reports have shown that there are differences between gefitinib responders and non-responders in the frequency of activating mutations and/or amplification in the EGFR gene, which suggests that such mutations might be predictive markers for sensitivity to gefitinib. However, there are known to be gefitinib-sensitive and intermediate-sensitive tumors that have no activating mutations in the EGFR gene, including gene amplification. SNPs in EGFR gene may be one of candidates for predictors of sensitivity. On the other hand, the incidence of gefitinib-induced lung injury was 3.98% in Japan(case-control study, AstraZeneca), which is higher than the correspondence rate, 0.3%, in the USA(FDA Approval Letter). Further studies about the prediction of drug-induced interstitial lung disease including SNPs analyses of the EGFR gene and other related molecules.

E-cadherin expression and epidermal growth factor receptor mutation status predict outcome in non-small cell lung cancer patients treated with gefitinib

It is known that an epidermal growth factor receptor (EGFR) gene mutation(s) is present in a percentage of non-small cell lung cancers (NSCLCs). Gefitinib, an inhibitor of the tyrosine kinase activity of EGFR, is effective on most of them. The EGFR mutation status alone cannot fully predict the response to gefitinib and the prognosis for the patients. We hypothesized that information on the expression levels of phosphorylated-EGFR and -Akt, and E-cadherin, alone or in combination with information on the EGFR mutation, may refine our ability of prediction. We investigated 24 NSCLCs that had recurred after surgery and were treated with gefitinib. Specimens resected by surgery were subjected to the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp reaction to determine the EGFR mutation status, and to immunohistochemical staining of phosphorylated-EGFR and -Akt, and E-cadherin to determine their expression levels. The EGFR mutation status was predictive of responsive disease (complete response: CR + partial response: PR) and controlled disease (CR + PR + stable disease: SD). Positive E-cadherin staining was predictive of longer time to progression (12.4 vs. 5.9 months, p<0.05) and overall survival (OS) (18.4 vs. 13.0 months, p<0.05). Together the patients with an EGFR mutation and the patients with positive E-cadherin staining defined a patient group with a median OS of 18.4 months and excluded the patient group with the median OS of 3.7 months. Neither p-Akt nor p-EGFR staining was associated with the response and survival. In patients with surgically resected NSCLC tumors, the EGFR mutation status and E-cadherin staining can select patients who will benefit from gefitinib therapy.

PTEN inactivation in lung cancer cells and the effect of its recovery on treatment with epidermal growth factor receptor tyrosine kinase inhibitors

To understand the mechanisms of PTEN inactivation, which is reported to be involved in tumor progression and drug resistance in lung cancer, we analyzed the expression levels of PTEN at mRNA and protein levels, along with the genetic and epigenetic status of the PTEN gene, in a panel of lung cancer cell lines. Western blot analysis showed that six out of 25 (24%) cell lines displayed low expression of PTEN protein. The level of PTEN mRNA correlated well with corresponding protein expression in each of these six cell lines. In two of the six cell lines genomic analysis revealed homozygous deletions of the PTEN gene. Another two of the six cell lines displayed hypermethylation of the PTEN gene promoter assessed by methylation-specific PCR. The levels of PTEN mRNA and protein expression in PC9/f9 and PC9/f14 cells, which are gefitinib-resistant derivatives of the gefitinib-sensitive cell line, PC9, were reduced compared to the parental line. After treatment with the demethylating agent 5-aza-2'deoxycytidine (5-AZA) and the histone deacetyltransferase (HDAC) inhibitor Trichostatin A (TSA), the expression levels of PTEN mRNA and protein in these four cell lines (PC9/f9, PC9/f14, PC10 and PC14) were actually restored. In summary, reduction in PTEN protein expression was regulated by histone deacetylation and hypermethylation of the gene promoter, as well as homozygous deletion. In addition, we demonstrated that the combination treatment of gefitinib and TSA induced significant growth inhibition in gefitinib-resistant PC9/f9 and PC9/f14 cells. These findings suggest that the combination of the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib with the demethylating agent 5-AZA and the HDAC inhibitor TSA may be a useful strategy for the treatment of some lung cancers.