Teh-Ying Chou

Identification of α-enolase as an autoantigen in lung cancer: Its overexpression is associated with clinical outcomes

Purpose: Although existence of humoral immunity has been previously shown in malignant pleural effusions, only a limited number of immunogenic tumor-associated antigens (TAA) have been identified and associated with lung cancer. In this study, we intended to identify more TAAs in pleural effusion–derived tumor cells. Experimental Design: Using morphologically normal lung tissues as a control lysate in Western blotting analyses, 54 tumor samples were screened with autologous effusion antibodies. Biochemical purification and mass spectrometric identification of TAAs were done using established effusion tumor cell lines as antigen sources. We identified a p48 antigen as α-enolase (ENO1). Semiquantitative immunohistochemistry was used to evaluate expression status of ENO1 in the tissue samples of 80 patients with non–small cell lung cancer (NSCLC) and then correlated with clinical variables. Results: Using ENO1-specifc antiserum, up-regulation of ENO1 expression in effusion tumor cells from 11 of 17 patients was clearly observed compared with human normal lung primary epithelial and non-cancer-associated effusion cells. Immunohistochemical studies consistently showed high level of ENO1 expression in all the tumors we have examined thus far. Log-rank and Coxs analyses of ENO1 expression status revealed that its expression level in primary tumors was a key factor contributing to overall- and progression-free survivals of patients (P < 0.05). The same result was also obtained in the early stage of NSCLC patients, showing that tumors expressing relatively higher ENO1 level were tightly correlated with poorer survival outcomes. Conclusions: Our data strongly support a prognostic role of ENO1 in determining tumor malignancy of patients with NSCLC.

Prognostic value of the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society lung adenocarcinoma classification on death and recurrence in completely resected stage I lung adenocarcinoma.

Objective: This study investigated the prognostic value of the new International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) lung adenocarcinoma classification in resected stage I lung adenocarcinoma. Methods: Histological classification of 283 patients undergoing surgical resection for stage I lung adenocarcinoma was determined according to the IASLC/ATS/ERS classification after comprehensive histological subtyping with recording of the percentage of each histological component (lepidic, acinar, papillary, micropapillary, and solid) in 5% increments. Their impact on overall survival, recurrence, and postrecurrence survival was investigated. Results: The 5-year overall survival and recurrence-free rates were 81.6% and 76.9%, respectively. During follow-up, 57 (20.1%) patients developed recurrence. The 2-year postrecurrence survival rate was 72.3%. The solid predominant group is associated with significant more male sex, higher smoking exposure, larger tumor size, and more poorly differentiated histological grade. Lepidic predominant group had significantly better overall survival (P = 0.002). Micropapillary and solid predominant groups had significantly lower probability of freedom from recurrence (P = 0.004). Older age (P = 0.039), visceral pleural invasion to the surface (PL2) (P = 0.009), and high grade (micropapillary/solid predominant) of the new classification (P = 0.028) were predictors of recurrence in multivariate analysis. The solid predominant group tends to have significantly worse postrecurrence survival (P = 0.074). Conclusions: The new adenocarcinoma classification has significant impact on death and recurrence in stage I lung adenocarcinoma. Patients with PL2 and micropapillary/solid predominant pattern have significant higher risk for recurrence. This information is important for patient stratification for aggressive adjuvant chemoradiation therapy.

Predictive Value of the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society Classification of Lung Adenocarcinoma in Tumor Recurrence and Patient Survival

PURPOSE This study investigated the pattern of recurrence of lung adenocarcinoma and the predictive value of histologic classification in resected lung adenocarcinoma using the new International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification system. PATIENTS AND METHODS Histologic classification of 573 patients undergoing resection for lung adenocarcinoma was determined according to the IASLC/ATS/ERS classification system, and the percentage of each histologic component (lepidic, acinar, papillary, micropapillary, and solid) was recorded. The pattern of recurrence of those components and their predictive value were investigated. RESULTS The predominant histologic pattern was significantly associated with sex (P < .01), invasive tumor size (P < .01), T status (P < .01), N status (P < .01), TNM stage (P < .01), and visceral pleural invasion (P < .01). The percentage of recurrence was significantly higher in micropapillary- and solid-predominant adenocarcinomas (P < .01). Micropapillary- and solid-predominant adenocarcinomas had a significantly higher possibility of developing initial extrathoracic-only recurrence than other types (P < .01). The predominant pattern group (micropapillary or solid v lepidic, acinar, or papillary) was a significant prognostic factor in overall survival (OS; P < .01), probability of freedom from recurrence (P < .01), and disease-specific survival (P < .01) in multivariable analysis. For patients receiving adjuvant chemotherapy, solid-predominant adenocarcinoma was a significant predictor for poor OS (P = .04). CONCLUSION In lung adenocarcinoma, the IASLC/ATS/ERS classification system has significant prognostic and predictive value regarding death and recurrence. Solid-predominant adenocarcinoma was also a significant predictor in patients undergoing adjuvant chemotherapy. Prognostic and predictive information is important for stratifying patients for aggressive adjuvant chemoradiotherapy.

Increased NBS1 Expression Is a Marker of Aggressive Head and Neck Cancer and Overexpression of NBS1 Contributes to Transformation

Purpose: Head and neck squamous cell carcinoma (HNSCC) represents the sixth most frequent type of cancer worldwide. However, the molecular genetic alterations underlying its malignant behavior and progression are little known. We showed previously that c-MYC directly activates the expression of the DNA double-strand break repair gene NBS1, and NBS1 overexpression contributes to transformation. Here, we investigate the role of NBS1 overexpression in HNSCC. Experimental Design: Immunohistochemistry analysis of NBS1 expression was done in 81 locally advanced HNSCC patients. Real-time PCR and Western blot analysis were used to confirm immunohistochemistry results. Human hypopharyngeal cancer cell lines (FADU) with overexpressing NBS1 (FADUNBS) or inducible short interference RNA to repress endogenous NBS1 (FADUNBSi) were generated by stable transfection. Soft agar clonogenicity assay was used to determine the transformation activity. Western blot analysis and phosphatidylinositol 3-kinase (PI3K) assay were done to evaluate the signaling pathways that were involved. Results: NBS1 overexpression was identified in 45% of advanced HNSCC patients. It was an independent marker of poor prognosis. NBS1 expression levels correlated with the transformation activity of FADU clones and also correlated with the phosphorylation levels of Akt and its downstream target mammalian target of rapamycin (mTOR). PI3K activity was increased in NBS1-overexpressing FADU clones. NBS1 overexpression also correlated with increased Akt phosphorylation levels in tumor samples. Conclusions: Increased NBS1 expression is a significant prognostic marker of advanced HNSCC, and the underlying mechanism may involve the activation of the PI3K/Akt pathway.

The role of mitochondrial DNA alterations in esophageal squamous cell carcinomas

OBJECTIVE The study objective was to evaluate the roles of mitochondrial DNA alterations in esophageal squamous cell carcinoma, with emphasis on the changes in the copy number and D310 variants of mitochondrial DNA. METHODS Paired samples microdissected from esophageal muscles, noncancerous esophageal mucosa, cancerous esophageal squamous cell carcinoma nests, and metastatic lymph nodes of 72 patients with esophageal squamous cell carcinoma were subjected to DNA extraction. The copy number and D310 variants of mitochondrial DNA were determined by quantitative real-time polymerase chain reaction and direct sequencing, respectively. RESULTS Fifty-six patients (77.8%) with somatic D310 mutations had lower survival probability (P = .027). From noncancerous esophageal mucosa to cancerous esophageal squamous cell carcinoma nests and metastatic lymph nodes, the D310 variants were decreased from 2.2 to 1.7 and 1.5, respectively, with a trend to homoplasmy (P = .0009). Concurrently, the mitochondrial DNA copy number was increased from 0.159 to 0.192 and 0.206, respectively, (P = .024), especially in cigarette smokers (P = .014) and heavy wine drinkers (P = .005). Notably, a decrease in D310 variants (1.5, P < .001) and an increase in the incidence of the homoplasmic D310 pattern (P = .005) were observed in the matched esophageal muscle tissues. Among the 56 esophageal squamous cell carcinoma cancer nests with somatic D310 mutations, 51 (91.1%) had D310 variants in association with their corresponding noncancerous esophageal mucosa, including 36 (64.3%) fully related and 15 (26.8%) partially related pairs. CONCLUSION We demonstrated that somatic D310 mutations and increase in the copy number of mitochondrial DNA are of clinical importance in esophageal squamous cell carcinoma. We also propose a model of DNA instability and clonal expansion during the carcinogenesis and progression of esophageal squamous cell carcinoma from the viewpoint of mitochondrial DNA transmission.

Prognostic Variables in Thoracic Esophageal Squamous Cell Carcinoma

BACKGROUND Thoracic esophageal squamous cell carcinoma (TESCC) is an aggressive malignancy with a poor prognosis. The current American Joint Committee on Cancer (AJCC) TNM cancer staging system focusing on the effect of regional (N1) and nonregional lymph node (M1a and M1b) metastasis may need reappraisal. We investigated the role of the number of dissected and positive nodes in TESCC patients. METHODS A total of 109 TESCC patients (97 men; mean age of 62.3 years) who underwent surgical resection were retrospectively analyzed. The current AJCC TNM system and other lymph node classifications were used to subgroup these patients and analyze survival differences. Previously reported prognostic factors were evaluated. RESULTS Patients with positive lymph node metastasis had a poor prognosis (p < 0.001). There was a significant difference in survival among the 67 node-positive patients subdivided into subgroups with 1 to 3 and 4 or more positive nodes (p = 0.004). Multivariable Cox proportional hazard regression analysis identified four independent prognostic factors: difficulty in swallowing (p = 0.024), cigarette smoking (p = 0.003), number of positive lymph nodes (0, 1 to 3, and > or = 4; p < 0.001), and gastric cardia invasion (p = 0.012). Total dissection of at least 20 lymph nodes was the minimal requirement to achieve accurate nodal staging. CONCLUSIONS Dissection of more than 20 lymph nodes is mandatory in TESCC patients to achieve accurate staging. Positive lymph node metastasis of 4 or higher is a significant independent prognostic factor.

Phase II randomized trial of erlotinib or vinorelbine in chemonaive, advanced, non-small cell lung cancer patients aged 70 years or older

Introduction: The primary objective of this study was to compare the response rates of elderly, chemonaive patients with advanced non-small cell lung cancer (NSCLC) treated with daily oral erlotinib versus oral vinorelbine. Methods: Chemonaive Taiwanese patients aged 70 years or older who had advanced NSCLC were randomized to receive either oral erlotinib 150 mg (E) daily or oral vinorelbine 60 mg/m2 (V) on days 1 and 8 every 3 weeks. Results: From February 2007 to July 2008, 116 patients were enrolled and 113 were included in the intent-to-treat population: 57 patients in the E group and 56 patients in the V group. Objective response rates were 22.8% (13 of 57) in E and 8.9% (5 of 56) in V (p = 0.0388). Median progression-free survival (PFS) was 4.57 months in E and 2.53 months in V (p = 0.0287), with an 80.6% increase in median PFS for E compared with V. Median survival time was 11.67 months in E and 9.3 months in V (p = 0.6975). Toxicities were generally mild in both groups. Median PFS was longest for epidermal growth factor receptor gene (EGFR)-mutated patients in the E group, followed by EGFR-mutated patients in V, EGFR wild type in E, and EGFR wild type in V (p = 0.0034). Overall survival was longer for EGFR-mutated patients than for EGFR wild-type patients (p < 0.0001). Conclusions: Erlotinib is highly effective compared with oral vinorelbine in elderly, chemonaive, Taiwanese patients with NSCLC. EGFR-mutated patients had better survival than those with EGFR wild-type disease, regardless of the treatment received.

EGFR Mutation Testing Practices within the Asia Pacific Region: Results of a Multicenter Diagnostic Survey

Introduction: The efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in EGFR mutation-positive non–small-cell lung cancer (NSCLC) patients necessitates accurate, timely testing. Although EGFR mutation testing has been adopted by many laboratories in Asia, data are lacking on the proportion of NSCLC patients tested in each country, and the most commonly used testing methods. Methods: A retrospective survey of records from NSCLC patients tested for EGFR mutations during 2011 was conducted in 11 Asian Pacific countries at 40 sites that routinely performed EGFR mutation testing during that period. Patient records were used to complete an online questionnaire at each site. Results: Of the 22,193 NSCLC patient records surveyed, 31.8% (95% confidence interval: 31.2%–32.5%) were tested for EGFR mutations. The rate of EGFR mutation positivity was 39.6% among the 10,687 cases tested. The majority of samples were biopsy and/or cytology samples (71.4%). DNA sequencing was the most commonly used testing method accounting for 40% and 32.5% of tissue and cytology samples, respectively. A pathology report was available only to 60.0% of the sites, and 47.5% were not members of a Quality Assurance Scheme. Conclusions: In 2011, EGFR mutation testing practices varied widely across Asia. These data provide a reference platform from which to improve the molecular diagnosis of NSCLC, and EGFR mutation testing in particular, in Asia.

Predictors of Death, Local Recurrence, and Distant Metastasis in Completely Resected Pathological Stage-I Non–Small-Cell Lung Cancer

Objective: This study investigated the factors predicting recurrence and death in patients with resected stage-I non–small-cell lung cancers according to the 7th edition of tumor, node, metastasis (TNM) classification for lung cancer. Methods: All patients undergoing surgical resection for pathological stage-I non–small-cell lung cancers at Taipei Veterans General Hospital between 1980 and 2000 were retrospectively reviewed. Those undergoing sublobar resection were excluded. The factors predicting overall survival (OS), overall recurrence, local recurrence, and distant metastasis were investigated. Results: A total of 756 patients were eligible. The 5-year OS rate and probability of freedom from recurrence were 57.3% and 70.2%, respectively. The 2-year local-recurrence–free and distant-metastasis–free rates were 90.7% and 82.1%, respectively. In multivariable analysis, the new T descriptor (T1a, T1b, and T2a) was the common factor that significantly affected OS (p = 0.003), overall recurrence (p = 0.004), and distant metastasis (p < 0.001). Smoking index more than 20, and number of mediastinal lymph nodes dissected/sampled of 15 or fewer were common factors that significantly predicted worse OS (p < 0.001, p < 0.001, respectively), lower probability of freedom from overall recurrence (p = 0.025, p = 0.009, respectively), and higher risk of local recurrence (p < 0.001, p = 0.030, respectively). Non–squamous-cell histology predicted higher risk of distant metastasis (p = 0.006). Conclusions: Risks of death and recurrence increase as the T descriptor upgrades in the new TNM system. The combination of risk factors can be used to identify high-risk subgroups of local recurrence and distant metastasis.

Clinical and testing protocols for the analysis of epidermal growth factor receptor mutations in East Asian patients with non-small cell lung cancer: a combined clinical-molecular pathological approach

Background: Several randomized phase III studies in advanced stage non-small cell lung cancer (NSCLC) confirmed the superior response rate and progression-free survival of using epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor as first-line therapy compared with chemotherapy in patients with activating EGFR mutations. Despite the need for EGFR mutation tests to guide first-line therapy in East Asian NSCLC, there are no current standard clinical and testing protocols. Methods: A consensus meeting was held involving expert oncologists, pulmonologists, and pathologists to discuss the current status and variations in EGFR mutation testing of NSCLC across Asia and to recommend a standard clinical and laboratory testing approach for future use. Results: Currently, EGFR mutation tests are only routinely performed in some East Asian countries and medical centers. The consensus recommendation was to perform the test in all newly diagnosed patients with advanced stage nonsquamous lung cancer and some squamous patients with clinical features associated with higher prevalence of EGFR mutations. To increase the sensitivity and specificity of the EGFR mutation tests, tissue acquisition and pretest sample evaluation are important steps in addition to standardization of the EGFR mutation test methodology. Conclusion: A standardized EGFR mutation testing protocol is an essential step toward realization of personalized medicine in East Asian NSCLC treatment.