EGFR Thr790Leu as a Potential Resistance Mechanism to First-Generation EGFR Tyrosine Kinase Inhibitor May Respond to Osimertinib in Patients With Lung Adenocarcinoma.

INTRODUCTION: It has been well established that EGFR Thr790Met is one of the major resistance mechanisms to first- and second-generation EGFR tyrosine kinase inhibitors (TKIs). Nevertheless, whether EGFR Thr790Leu (T790L), which shares the mutation site of Thr790 with EGFR Thr790Met, mediates resistance to EGFR TKIs remains elusive. The treatment options for patients harboring this rare mutation have not been reported. METHODS: Capture-based targeted ultradeep sequencing was performed on tumor and plasma samples collected at various treatment milestones from three patients with advanced lung adenocarcinoma undergoing targeted therapy. RESULTS: Needle biopsy of lymph node metastasis from patient 1 revealed EGFR T790L at disease progression on first-line treatment of gefitinib. Patient 2 had EGFR T790L identified from needle biopsy of lung tissue at disease progression on icotinib treatment. This patient was subsequently treated with osimertinib and achieved stable disease with a progression-free survival of 9 months. For patient 3, at disease recurrence after surgery, resected lung tumor tissue was retrieved for molecular profiling and revealed EGFR exon 19 deletion and EGFR T790L. The patient subsequently received osimertinib treatment and continued to benefit for 16 months and counting. She has maintained stable disease at the time of submission of this manuscript. CONCLUSIONS: We revealed for the first time that EGFR T790L may serve as a potential resistance mechanism to first-generation EGFR TKIs. We also report the first clinical evidence of efficacy generated by osimertinib in patients with lung adenocarcinoma harboring primary or acquired EGFR T790L, shedding light on treatment options for this subset of patients.

Lack of association between XRCC3 rs861539 (C > T) polymorphism and lung cancer risks: an update meta-analysis.

X-ray repair cross-complementing protein 3 (XRCC3) belongs to DNA double-strand break repair pathway and XRCC3 rs861539 (C > T) polymorphism has been suspected with lung cancer risk. However, results from previous studies are inconclusive and affected by bias. Electronic databases of PubMed, EMBASE, China National Knowledge Infrastructure, and SinoMed were searched. References of relative reviews were also screened. Pooled odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated to estimate the association strength. A number of 18 eligible studies with 6 studies of Asians, 11 of Caucasians, and 1 of African were extracted and analyzed, including 4,896 lung cancer cases and 6,360 controls. No significant correlation between XRCC3 polymorphism and lung cancer risk was observed in homozygote comparison (CC vs. TT; OR=0.877; 95 % CI, 0.659, 1.168), heterozygote comparison (CT vs. TT; OR=0.857; 95 % CI, 0.675, 1.089), dominant model (CC/CT vs. TT; OR=0.862; 95 % CI, 0.663, 1.123), or recessive model (CC vs. CT/TT; OR=1.047; 95 % CI, 0.956, 1.145). Subgroup analyses of ethnicity and controls did not reveal any significant association with lung cancer risk. No publication bias was detected. In this update meta-analysis of 18 studies and 11,256 participants, we find that XRCC3 rs861539 polymorphism does not contribute to lung cancer risk and there is no difference between Asians and Caucasians.

A classification method based on principal components of SELDI spectra to diagnose of lung adenocarcinoma.

PURPOSE: Lung cancer is the leading cause of cancer death worldwide, but techniques for effective early diagnosis are still lacking. Proteomics technology has been applied extensively to the study of the proteins involved in carcinogenesis. In this paper, a classification method was developed based on principal components of surface-enhanced laser desorption/ionization (SELDI) spectral data. This method was applied to SELDI spectral data from 71 lung adenocarcinoma patients and 24 healthy individuals. Unlike other peak-selection-based methods, this method takes each spectrum as a unity. The aim of this paper was to demonstrate that this unity-based classification method is more robust and powerful as a method of diagnosis than peak-selection-based methods. RESULTS: The results showed that this classification method, which is based on principal components, has outstanding performance with respect to distinguishing lung adenocarcinoma patients from normal individuals. Through leaving-one-out, 19-fold, 5-fold and 2-fold cross-validation studies, we found that this classification method based on principal components completely outperforms peak-selection-based methods, such as decision tree, classification and regression tree, support vector machine, and linear discriminant analysis. CONCLUSIONS AND CLINICAL RELEVANCE: The classification method based on principal components of SELDI spectral data is a robust and powerful means of diagnosing lung adenocarcinoma. We assert that the high efficiency of this classification method renders it feasible for large-scale clinical use.

Expression of GPC3 protein and its significance in lung squamous cell carcinoma.

The purpose of this study was to investigate GPC3 gene expression in lung squamous cell carcinoma tissue and its correlation with clinical and tumor characteristics. Using RT-PCR, the presence of GPC3 gene expression was detected in cancer tissue and adjacent normal tissue in 66 cases of lung squamous cell carcinoma and positive rates were calculated. Using Western blot, changes in GPC3 protein expression were detected in lung squamous cell carcinoma and adjacent normal tissues. The percentage of tissue samples expressing GPC3 mRNA was significantly higher in lung squamous cell carcinoma than in adjacent normal tissue (P < 0.05). This percentage was also significantly higher for cases with lymph node metastasis than for those without lymph node metastasis (P < 0.05). Further, the percentage of samples expressing GPC3 mRNA was higher with lowering degrees of tumor differentiation (P < 0.05). Rates of GPC3 expression were, however, independent of patient gender, age, and tumor size (P > 0.05). The expression of GPC3 protein in lung squamous cell carcinoma was significantly higher than that in adjacent normal tissues (P < 0.05). The expression in cases with lymph node metastasis was significantly higher than in those without lymph node metastasis (P < 0.05), and GPC3 protein expression increased with lowering degrees of tumor differentiation (P < 0.05). Further investigation is warranted for the association of initiation, development, invasion, and metastasis of disease.

Prognostic impact of vascular endothelial growth factor-A and E-cadherin expression in completely resected pathologic stage I non-small cell lung cancer.

OBJECTIVE: The purpose of this study was to evaluate the value of vascular endothelial growth factor-A and E-cadherin expression as well as other confirmed prognostic factors in predicting the clinical outcome after definitive surgery of pathologic stage I non-small cell lung cancer. METHODS: One hundred and eighty-five consecutive and non-selected patients who underwent definitive surgery for stage I non-small cell lung cancer in our institute were included in this study. Formalin-fixed paraffin-embedded specimens were stained for vascular endothelial growth factor-A and E-cadherin and the correlation between the staining, its clinicopathological parameters and its prognostic power were analyzed statistically. RESULTS: Of the 185 patients studied, 92 cases (49.7%) were strongly positive for vascular endothelial growth factor-A. Vascular endothelial growth factor-A expression was only related to visceral pleural involvement (P < 0.001). A total of 95 carcinomas (51.4%) were E-cadherin-negative tumors. E-cadherin expression correlated with histology (P < 0.001), tumor size (P = 0.001) and visceral pleural involvement (P < 0.001). In univariate analysis by log-rank test, gender, tumor size, lymphovascular invasion, visceral pleural involvement, vascular endothelial growth factor-A expression and E-cadherin expression were significant prognostic factors (P = 0.003, 0.042, 0.026, 0.035, 0.008 and 0.006, respectively). In multivariate analysis, gender, vascular endothelial growth factor-A and E-cadherin expression maintained its independent prognostic influence on overall survival (P = 0.013, <0.001 and 0.036, respectively). CONCLUSIONS: Expression of vascular endothelial growth factor-A is related to visceral pleural involvement, and E-cadherin expression correlates with histology, tumor size and visceral pleural involvement. Multivariate analysis confirmed gender, vascular endothelial growth factor-A and E-cadherin expression were significant predictive factors for overall survival in completely resected pathologic stage I non-small cell lung cancer.

[Clinical observation of gefitinib for the treatment of 125 cases with advanced non-small cell lung cancer].

OBJECTIVE: To evaluate the efficacy and safety of gefitinib for the treatment of advanced non-small cell lung cancer (NSCLC). METHODS: 125 patients with advanced NSCLC who had failed or not tolerated or refused chemotherapy received 250 mg oral doses of gefitinib once daily until the disease progression or intolerable toxicity. RESULTS: A total of 125 NSCLC patients were studied, the overall response rate (RR) and the disease control rate (DCR) after administration of gefitinib were 35.2% (44/125) and 77.6% (97/125), respectively. The median progression-free survival and the median survival time were 5.8 and 11.2 months, respectively. The one-year survival rate was 40.5%. The response rate was significantly higher in females, adenocarcinoma and nonsmokers than that in males, non-adenocarcinoma and smokers (P < 0.05). The response rate did not show significant differences regarding ECOG score or previous treatment. The median progression-free survival was significantly longer in ECOG PS 0-1 and gefitinib effective patients than that in ECOG PS >or= 2 and gefitinib ineffective patients (P < 0.01). The median survival time was significantly longer in adenocarcinoma, nonsmokers and gefitinib effective patients than that in non-adenocarcinoma, smokers and gefitinib ineffective patients (P < 0.05). The most common side effects were rash (51.2%) and diarrhea (34.4%), but usually were mild. CONCLUSION: Gefitinib is effective and safe in the treatment of advanced NSCLC patients.

[Randomized study of thalidomide combined with vinorelbine and cisplatin chemotherapy for the treatment of advanced non-small cell lung cancer].

OBJECTIVE: To evaluate the efficacy, median time to progression (TTP), quality of life and toxicity in the patients with advanced non-small cell lung cancer (NSCLC), treated with thalidomide plus vinorelbine and cisplatin (NP) or NP alone. METHODS: Sixty six patients with advanced NSCLC were divided randomly into two groups, the trial and control groups. The trial group was treated with vinorelbine 25 approximately 30 mg/m(2) i.v. on D1 and D8, cisplatin 70 approximately 80 mg/m(2) i.v. on D1 (NP regimen), and thalidomide 200 mg orally and daily from D1. The control group received vinorelbine and cisplatin as above described. RESULTS: Of 66 assessable patients, the overall response rate was 51.5% in the trial group and 36.4% in the control group (P = 0.22). The median TTP was 6.0 months for the trial group, and 3.6 months for the control group (P < 0.001). The score of quality of life in trial group was higher than that in the control group, but no significant difference was observed between the two groups (P > 0.05). There were no significant differences in toxicities between the two groups (P > 0.05). CONCLUSION: NP regimen combined with thalidomide can significantly prolong the median time to tumor progression in patients with advanced NSCLC. Thalidomide may have a synergic activity with NP regimen without increased toxicities.