Meng-Feng Tsai

Curcumin inhibits lung cancer cell invasion and metastasis through the tumor suppressor HLJ1.

Curcumin (diferuloylmethane) is an active component of the spice turmeric and has a diversity of antitumor activities. In this study, we found that curcumin can inhibit cancer cell invasion and metastasis through activation of the tumor suppressor DnaJ-like heat shock protein 40 (HLJ1). Human lung adenocarcinoma cells (CL1-5) treated with curcumin (1-20 mumol/L) showed a concentration-dependent reduction in cell migration, invasion, and metastatic ability, and this was associated with increased HLJ1 expression. Knockdown of HLJ1 expression by siRNA was able to reverse the curcumin-induced anti-invasive and antimetastasis effects in vitro and in vivo. The HLJ1 promoter and enhancer in a luciferase reporter assay revealed that curcumin transcriptionally up-regulates HLJ1 expression through an activator protein (AP-1) site within the HLJ1 enhancer. JunD, one of the AP-1 components, was significantly up-regulated by curcumin (1-20 mumol/L) in a concentration- and time-dependent manner. Knockdown of JunD expression could partially reduce the curcumin-induced HLJ1 activation and diminish the anti-invasive effect of curcumin, indicating that JunD would seem to be involved in curcumin-induced HLJ1 expression. Curcumin was able to induce c-Jun NH(2)-kinase (JNK) phosphorylation, whereas the JNK inhibitor (SP-600125) could attenuate curcumin-induced JunD and HLJ1 expression. Activation of HLJ1 by curcumin further leads to up-regulation of E-cadherin and a suppression of cancer cell invasion. Our results show that curcumin induces HLJ1, through activation of the JNK/JunD pathway, and inhibits lung cancer cell invasion and metastasis by modulating E-cadherin expression. This is a novel mechanism and supports the application of curcumin in anti-cancer metastasis therapy.

ALDH-positive lung cancer stem cells confer resistance to epidermal growth factor receptor tyrosine kinase inhibitors

Molecular targeting therapeutics, such as EGFR tyrosine kinase inhibitors (TKIs), are important treatment strategies for lung cancer. Currently, the major challenge confronting targeted cancer therapies is the development of resistance. Cancer stem cells (CSCs) represent a rare population of undifferentiated tumorigenic cells responsible for tumor initiation, maintenance and spreading. Resistance to conventional chemotherapeutic drugs is a common characteristic of CSCs. However, the issue of whether CSCs contribute to EGFR TKI resistance in lung cancer is yet to be established. In the current study, we explored the association of ALDH1A1 expression with EGFR TKI resistance in lung cancer stem cells. ALDH1A1-positive lung cancer cells displayed resistance to gefitinib, compared to ALDH1A1-negative lung cancer cells. Moreover, PC9/gef cells (gefitinib-resistant lung cancer cells) presented a higher proportion of ALDH1A1-positive cells, compared to PC9 cells (gefitinib-sensitive lung cancer cells). Clinical sample studies were consistent with results from cell culture model systems showing that lung cancer cells with resistance to EGFR TKI and chemotherapy drugs contain significantly increased proportions of ALDH1A1-positive cells. These findings collectively suggest that ALDH1A1 positivity in cancer stem cells confers resistance to EGFR TKI in lung cancer.

EML4-ALK Translocation Predicts Better Outcome in Lung Adenocarcinoma Patients with Wild-Type EGFR

Introduction: The echinoderm microtubule-associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) fusion represents a novel target in a subset of non-small cell lung cancer, especially adenocarcinoma. EML4-ALK fusion is mutually exclusive with epidermal growth factor receptor (EGFR) mutations. To understand the impact of EML4-ALK on the prognosis of non-small cell lung cancer, we examined EML4-ALK fusion in lung adenocarcinoma from patients with wild-type EGFR and analyzed their clinical treatment outcomes. Methods: Lung adenocarcinoma patients with malignant pleural effusions having wild-type EGFR and measurable target lesions were enrolled for EML4-ALK analysis by reverse transcription-polymerase chain reaction and direct sequencing. Demographic data, EML4-ALK status, and survival data were analyzed. We also performed fluorescence in situ hybridization on some available tumor samples to validate the PCR result. In addition, K-ras mutation was analyzed for patients without EML4-ALK fusion genes. Results: A total of 116 patients with wild-type EGFR sequencing results had complete clinical data for analysis. No patients received ALK inhibitor therapy. There were 39 patients (34%) with the EML4-ALK fusion gene. The concordance rate between reverse transcription-polymerase chain reaction and fluorescence in situ hybridization was 85%. The K-ras mutation rate for patients without EML4-ALK fusion gene was 6.5%. By multivariate analysis, patients who had better performance status (p < 0.001) and EML4-ALK translocation (p = 0.017) had longer overall survival. Comparing patients with tumors harboring variant 1 with those harboring nonvariant 1 EML4-ALK fusion genes, there were no significant differences in clinical factors and survival outcome. Conclusion: For lung adenocarcinoma patients with wild-type EGFR, EML4-ALK translocation is associated with longer overall survival.

The mechanism of acquired resistance to irreversible EGFR tyrosine kinase inhibitor-afatinib in lung adenocarcinoma patients

Introduction Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are associated with favorable response in EGFR mutant lung cancer. Acquired resistance to reversible EGFR TKIs remains a significant barrier, and acquired EGFR T790M-mutation is the major mechanism. Second-generation irreversible EGFR TKI, afatinib, had also been approved for treating EGFR mutant lung cancer patients, but the mechanism of acquired resistance to afatinib has not been well studied. Results Forty-two patients had tissue specimens taken after acquiring resistance to afatinib. The sensitizing EGFR mutation were all consistent between pre- and post-afatinib tissues. Twenty patients (47.6%) had acquired T790M mutation. T790M rate was not different between first-generation EGFR TKI-naïve patients (50%) and first-generation EGFR TKI-treated patients (46.4%) (p = 0.827). No clinical characteristics or EGFR mutation types were associated with the development of acquired T790M. No other second-site EGFR mutations were detected. There were no small cell or squamous cell lung cancer transformation. Other genetic mutations were not identified in PIK3CA, BRAF, HER2, KRAS, NRAS, MEK1, AKT2, LKB1 and JAK2. Methods Afatinib-prescription record of our department of pharmacy from January 2007 and December 2014 was retrieved. We investigated patients with tissue specimens available after acquiring resistance to afatinib. Enrolled patients should have partial response or durable stable disease of treatment response to afatinib. Various mechanisms of acquired resistance to first-generation EGFR TKIs were evaluated. Histology and cytology were reviewed. EGFR, PIK3CA, BRAF, HER2, KRAS, NRAS, MEK1, AKT2, LKB1 and JAK2 genetic alterations were evaluated by sequencing. Statistical analysis was performed using Chi-square test and Kaplan-Meier method. Conclusions T790M was detected in half of the lung adenocarcinoma after acquiring resistance to afatinib. T790M is still the major acquired resistance mechanism. First-generation EGFR TKI exposure did not influence the prevalence of T790M in lung cancer acquired resistance to afatinib.

Good response to gefitinib in lung adenocarcinoma of complex epidermal growth factor receptor (EGFR) mutations with the classical mutation pattern.

BACKGROUND Epidermal growth factor receptor (EGFR) mutations are usually detected in lung adenocarcinoma and are associated with a response to EGFR tyrosine kinase inhibitors (TKIs). However, not all EGFR mutations have similarly high clinical response rates. This study aimed to investigate the clinical characteristics and response to gefitinib in lung adenocarcinoma patients with complex EGFR mutations. MATERIALS AND METHODS Three hundred thirty-nine specimens of lung adenocarcinoma from patients treated with gefitinib were collected for EGFR sequencing. Nineteen patients with complex EGFR mutations were enrolled for the study after excluding three patients with the EGFR T790M mutation, which confers resistance to gefitinib. RESULTS Among the 19 patients, 12 had complex mutations with the classical mutation pattern (L858R or deletion in exon 19). When compared with those without the classical mutation pattern, patients with this mutation pattern had a higher response rate (83% versus 29%), longer progression-free survival duration (median, 12.7 months versus 4.9 months), and longer overall survival time (median, 24.7 months versus 12.3 months) after gefitinib treatment. Comparing patients harboring complex EGFR mutations with a classical mutation pattern with those harboring single classical mutations, there were no statistical differences in the response rate (83% versus 73%), progression-free survival time (median, 12.7 months versus 8.1 months,) or overall survival time (median, 24.7 months versus 16.4 months). CONCLUSION Patients with complex EGFR mutations with the classical mutation pattern had the same response rate, progression-free survival duration, and overall survival time as those with single classical mutations. EGFR TKIs may be the choice of treatment for this type of lung adenocarcinoma.

Survival of lung adenocarcinoma patients with malignant pleural effusion

In the era of targeted therapy, the association between lung adenocarcinoma patient survival and malignant pleural effusions (MPEs) remains unclear. This study investigated the clinical characteristics, survival and epidermal growth factor receptor (EGFR) gene (EGFR) mutation status of lung adenocarcinoma patients with MPE. From June 2005 to December 2010, consecutive pleural effusions were collected prospectively. Patient clinical characteristics, EGFR mutation status, and overall survival were analysed. We collected MPEs from 448 patients in stage IV lung adenocarcinoma at initial diagnosis. Median overall survival for patients with MPEs at initial diagnosis and following disease progression were 14.3 months and 21.4 months, respectively (p=0.001). There were 296 (66.1%) patients harbouring EGFR mutations, the mutation rates among patients with an MPE at initial diagnosis and one following disease progression were 68.2% and 56.6%, respectively (p=0.044); the L858R mutation rate was also higher among the former (32.6% versus 18.1%; p=0.009). Multivariate analysis revealed that patients who: developed MPEs following disease progression, harboured EGFR mutations, and received EGFR-tyrosine kinase inhibitor therapy, had longer overall survival. Patients in stage IV lung adenocarcinoma with MPEs at initial diagnosis have shorter overall survival and higher EGFR mutation rate, especially for L858R, than patients who develop MPEs following disease progression.

Including Total EGFR Staining in Scoring Improves EGFR Mutations Detection by Mutation-Specific Antibodies and EGFR TKIs Response Prediction

Epidermal growth factor receptor (EGFR) is a novel target for therapy in subsets of non-small cell lung cancer, especially adenocarcinoma. Tumors with EGFR mutations showed good response to EGFR tyrosine kinase inhibitors (TKIs). We aimed to identify the discriminating capacity of immunohistochemical (IHC) scoring to detect L858R and E746-A750 deletion mutation in lung adenocarcinoma patients and predict EGFR TKIs response. Patients with surgically resected lung adenocarcinoma were enrolled. EGFR mutation status was genotyped by PCR and direct sequencing. Mutation-specific antibodies for L858R and E746-A750 deletion were used for IHC staining. Receiver operating characteristic (ROC) curves were used to determine the capacity of IHC, including intensity and/or quickscore (Q score), in differentiating L858R and E746-A750 deletion. We enrolled 143 patients during September 2000 to May 2009. Logistic-regression-model-based scoring containing both L858R Q score and total EGFR expression Q score was able to obtain a maximal area under the curve (AUC: 0.891) to differentiate the patients with L858R. Predictive model based on IHC Q score of E746-A750 deletion and IHC intensity of total EGFR expression reached an AUC of 0.969. The predictive model of L858R had a significantly higher AUC than L858R intensity only (p = 0.036). Of the six patients harboring complex EGFR mutations with classical mutation patterns, five had positive IHC staining. For EGFR TKI treated cancer recurrence patients, those with positive mutation-specific antibody IHC staining had better EGFR TKI response (p = 0.008) and longer progression-free survival (p = 0.012) than those without. In conclusion, total EGFR expression should be included in the IHC interpretation of L858R. After adjusting for total EGFR expression, the scoring method decreased the false positive rate and increased diagnostic power. According to the scoring method, the IHC method is useful to predict the clinical outcome and refine personalized therapy.

Clinical and the Prognostic Characteristics of Lung Adenocarcinoma Patients with ROS1 Fusion in Comparison with Other Driver Mutations in East Asian Populations

Introduction: The prevalence, demographic features, and clinical outcomes of lung adenocarcinoma patients with novel ROS1 oncogenic rearrangement in East Asian populations are not clear. This study aimed to investigate the clinical and prognostic characteristics of lung adenocarcinoma in patients with ROS1 fusion compared with other driver mutations. Methods: Multiplex reverse transcription-polymerase chain reaction was used to detect the ROS1 fusion gene in lung adenocarcinoma cases. Immunohistochemistry was used to confirm the expression of ROS1. The demographic data and clinical outcomes of patients with the ROS1 fusion gene were compared with those of patients without the ROS1 fusion gene, including those with the EGFR mutation, EML4-ALK fusion, KRAS mutation, and quadruple-negative patients. Results: Of 492 patients with lung adenocarcinoma, 12 (2.4%) had the ROS1 fusion gene. Their median age was 45.0 years, significantly younger than that of the ROS1 fusion-negative cohorts (p < 0.001). Acinar (including cribriform) and solid patterns were the two most common histologic subtypes in the ROS1 fusion tumors (7 of 12, 58.3%) and were predominantly seen in CD74-ROS1 fusion tumors (66.7%). There was no significant survival difference between the ROS1 fusion-positive and ROS1 fusion-negative cohorts in surgical group, but ROS1 fusion-positive patients might have worse outcomes than EGFR-mutant patients in the stage IV group. Conclusions: The ROS1 fusion gene can be successfully detected in East Asian patients with lung adenocarcinoma using multiplex reverse transcription-polymerase chain reaction. These patients tend to be younger and have characteristic histologic subtypes. Due to the small number of ROS1 fusion patients, the prognostic value of ROS1 fusion need further studies to confirm.

Effusion Immunocytochemistry as an Alternative Approach for the Selection of First-Line Targeted Therapy in Advanced Lung Adenocarcinoma

Introduction: Tumor tissue is often not obtainable or suitable for molecular-based epidermal growth factor receptor (EGFR) mutational analysis in advanced non–small-cell lung cancer (NSCLC). This retrospective and single-institution study was conducted to evaluate the role of effusion immunocytochemistry using two EGFR mutant-specific antibodies for the detection of relevant EGFR mutations in NSCLC, along with the selection of candidates for first-line therapy with EGFR tyrosine kinase inhibitors (TKIs). Methods: Immunocytochemistry using two antibodies binding specifically to the major forms of mutant EGFR, L858R, and E746-A750 deletion (delE746-A750), was performed on cell blocks of malignant pleural effusion (MPE) from 78 patients with lung adenocarcinoma, who received first-line EGFR TKIs. The yield of EGFR-mutation detection and prediction of response rate and progression-free survival to TKI treatment by immunocytochemistry were compared with those by clinical characteristics and EGFR sequencing using cell-derived RNA from MPEs. Results: Of the 78 MPE samples, direct sequencing using cell-derived RNA identified L858R mutation in 42 cases, deletions in exon 19 in 12 cases (delE746-A750 in eight cases), other types of mutations in three cases, and wild-type EGFR in 21 cases. Effusion immunocytochemistry with these two mutant-specific antibodies exhibited a sensitivity of 71% and 88% and a specificity of 86% and 96% for identifying predefined L858R and delE746-A750 mutations, respectively. Effusion immunocytochemistry provided a superior prediction of tumor response and progression-free survival to first-line EGFR TKIs than did clinical characteristics like sex and smoking status. Patients whose effusion immunocytochemistry showed a reaction to either of the two antibodies had a comparable TKI response rate (67% versus 72%) to those with EGFR mutations assessed by direct sequencing from cell-derived RNA. Conclusions: Effusion immunocytochemistry could be introduced into clinical practice to identify more NSCLC patients likely to have benefit from first-line TKI treatment, especially for those without adequate tissue for molecular-based EGFR analysis.

Global expression profiling of theophylline response genes in macrophages: evidence of airway anti-inflammatory regulation

BackgroundTheophylline has been used widely as a bronchodilator for the treatment of bronchial asthma and has been suggested to modulate immune response. While the importance of macrophages in asthma has been reappraised and emphasized, their significance has not been well investigated. We conducted a genome-wide profiling of the gene expressions of macrophages in response to theophylline.MethodsMicroarray technology was used to profile the gene expression patterns of macrophages modulated by theophylline. Northern blot and real-time quantitative RT-PCR were also used to validate the microarray data, while Western blot and ELISA were used to measure the levels of IL-13 and LTC4.ResultsWe identified dozens of genes in macrophages that were dose-dependently down- or up-regulated by theophylline. These included genes related to inflammation, cytokines, signaling transduction, cell adhesion and motility, cell cycle regulators, and metabolism. We observed that IL-13, a central mediator of airway inflammation, was dramatically suppressed by theophylline. Real-time quantitative RT-PCR and ELISA analyses also confirmed these results, without respect to PMA-treated THP-1 cells or isolated human alveolar macrophages. Theophylline, rolipram, etazolate, db-cAMP and forskolin suppressed both IL-13 mRNA expression (~25%, 2.73%, 8.12%, 5.28%, and 18.41%, respectively) and protein secretion (<10% production) in macrophages. These agents also effectively suppressed LTC4 expression.ConclusionOur results suggest that the suppression of IL-13 by theophylline may be through cAMP mediation and may decrease LTC4 production. This study supports the role of theophylline as a signal regulator of inflammation, and that down regulation of IL-13 by theophylline may have beneficial effects in inflammatory airway diseases.