ABSTRACT
Alterations of the epidermal growth factor receptor (EGFR), including overexpression or gene mutations, contribute to the malignant transformation of human epithelial cells. The aim of this study was to assess EGFR overexpression or gene amplification in esophageal squamous cell carcinoma (ESCC) tissue samples and investigate their correlations with biological behaviors. Tissue specimens from 56 patients with surgically resected ESCC were obtained for immunohistochemical analysis of EGFR expression and fluorescence in situ hybridization analysis of EGFR amplification. The data were statistically analyzed to determine the associations with patient clinicopathological and survival data. EGFR was overexpressed in 30 of the 56 (53.6%) ESCC samples and was associated with poor tumor differentiation (P=0.047). EGFR amplification was detected in 13 cases (23.2%) and was associated with advanced pathological stage (P=0.042) and tumor lymph node metastasis (P=0.002). The univariate analysis identified no association between EGFR overexpression and the overall survival (OS) of the patients. By contrast, EGFR amplification predicted ESCC prognosis (P=0.031), while the multivariate analysis revealed a marginal statistical significance for the association between EGFR amplification and OS (P=0.056). EGFR overexpression and increased EGFR copy number were common events in ESCC and contributed to malignant biological behaviors, including tumor dedifferentiation and lymph node metastasis. EGFR amplification may therefore be useful in predicting OS in patients with ESCC.
ABSTRACT
Non-small cell lung cancer is a subtype of adenocarcinoma, which has previously shown positive responses to gefitinib. The aim of the current study was to determine a clinical profile of gefitinib-induced disease controls for patients with lung adenocarcinoma. Retrospective evaluation of the clinical characteristics of 52 lung adenocarcinoma patients, enrolled at the Zhejiang Cancer Hospital (Hangzhou, China) between October 2004 and August 2008, was undertaken. All patients received gefitinib (250 mg/day orally) until disease progression or until an unacceptable toxicity was observed. Of the 52 patients, complete response (CR) and partial response (PR) rates were 23.1% (12/52) and 57.7% (30/52), respectively. An additional 19.2% (10/52) of patients demonstrated stable disease (SD) after three months of treatment with gefitinib. Disease control was observed in the primary lesion, and tumor metastasis to the lungs, brain, adrenal glands, pleura, peritoneum, pericardium, bone and lymph nodes was identified. The one-year progression-free survival (PFS) and overall survival (OS) rates were 74.8 and 78.0%, respectively. Multivariate analysis revealed that female patients were associated with significantly longer survival times when compared with males (hazard ratio, 0.077; 95% confidence interval [CI], 0.007-0.083; P=0.035). One-year PFS and OS rates in CR, PR and SD patients were 77.8, 73.9 and 33.3%, and 89.2, 79.8 and 33.7%, respectively, although neither difference was identified to be statistically significant. In addition, the median OS of SD patients was 12 months (95% CI, 7.2-16.8 months). Brain metastasis was the major site of disease progression (23.1%). Gefitinib treatment for patients with lung adenocarcinoma showed a marked long-term survival benefit, even in SD patients. However, further studies are required to analyze the efficacy of gefitinib in penetrating the blood-brain barrier in order to prolong PFS in patients with lung adenocarcinoma.
ABSTRACT
DNA repair capacity is correlated with the sensitivity of cancer cells toward platinum-based chemotherapy. The aim of this study was to investigate whether single-nucleotide polymorphisms (SNPs) in DNA repair genes NBS1, LIG4, and RAD51 were correlated with tumor response in advanced non-small cell lung cancer (NSCLC) patients in a Chinese population who received platinum-based chemotherapy. The treatment outcomes of 146 advanced NSCLC patients who were treated with platinum-based chemotherapy were evaluated. The polymorphic status of three SNPs was determined by genotyping via the polymerase chain reaction-restriction fragment length polymorphism method. Forty-five patients in the group with the CC genotype (45/90) showed a good response to treatment, while only 18 patients in the CT+TT group (18/55) showed a good response, indicating a substantial differences in the chemotherapy response rate based on the LIG4 Thr9Ile polymorphism (P = 0.042). Patients with the GG genotype for the NSB1 Glu185Gln polymorphism were more sensitive to platinum-based chemotherapy compared with patients with either the CG or CC genotype (P = 0.001). Kaplan-Meier analysis of all patients showed a significant association between the LIG4 Thr9Ile CC polymorphism and superior progression-free survival and overall survival (log-rank P = 0.045 and 0.031, respectively). However, there were no significant differences in survival based on the LIG4 Thr9Ile or the RAD51 135G>C polymorphisms. Polymorphisms in the NSB1 and LIG4 genes may be a predictive marker for treatment response and for advanced NSCLC patients in stage IIIB + IV. The CC genotype of the LIG4 Thr9Ile polymorphism may also serve as an independent prognosis factor.
