Guanghui Gao

Epidermal growth factor receptor-tyrosine kinase inhibitor therapy is effective as first-line treatment of advanced non-small-cell lung cancer with mutated EGFR: A meta-analysis from six phase III randomized controlled trials.

Gefiinib and erlotinib are two similar small molecules of selective and reversible epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKIs), which have been approved for second‐line or third‐line indication in previously treated advanced Non‐small‐cell lung cancer (NSCLC) patients. The results of comparing the EGFR‐TKI with standard platinum‐based doublet chemotherapy as the first‐line treatment in advanced NSCLC patients with activated EGFR mutation were still controversial. A meta‐analysis was performed to derive a more precise estimation of these regimens. Finally, six eligible trials involved 1,021 patients were identified. The patients receiving EGFR‐TKI as front‐line therapy had a significantly longer progression‐free survival (PFS) than patients treated with chemotherapy [median PFS was 9.5 versus 5.9 months; hazard ratio (HR) = 0.37; 95% confidence intervals (CI) = 0.27–0.52; p < 0.001]. The overall response rate (ORR) of EGFR‐TKI was 66.60%, whereas the ORR of chemotherapy regimen was 30.62%, which was also a statistically significant favor for EGFR‐TKI [relative risk (RR) = 5.68; 95% CI = 3.17–10.18; p < 0.001]. The overall survival (OS) was numerically longer in the patients received EGFR‐TKI than patients treated by chemotherapy, although the difference did not reach a statistical significance (median OS was 30.5 vs. 23.6 months; HR = 0.94; 95% CI = 0.77–1.15; p = 0.57). Comparing with first‐line chemotherapy, treatment of EGFR‐TKI achieved a statistical significantly longer PFS, higher ORR and numerically longer OS in the advanced NSCLC patients harboring activated EGFR mutations, thus, it should be the first choice in the previously untreated NSCLC patients with activated EGFR mutation.

MiR-21 overexpression is associated with acquired resistance of EGFR-TKI in non-small cell lung cancer

BACKGROUND AND PURPOSE With the increasing use of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) in patients with advanced non-small cell lung cancer (NSCLC), its acquired resistance has become a major clinical problem. Recent studies revealed that miR-21 was involved into the resistance of cytotoxic agents. The aim of this study was to investigate its role in the acquired resistance of NSCLC to EGFR-TKI. METHODS EGFR-TKI-sensitive human lung adenocarcinoma cell line PC9 and the acquired resistant cell line, PC9R, were used. Lentiviral vectors were used to infect PC9 or PC9R to regulate the miR-21 expression. The expression of targeted proteins PTEN and PDCD4 was controlled by RNA interference. MicroRNA array, RT-PCR and TaqMan MicroRNA Assays were used to detect miR-21 expression. The MTT and Annexin V assays were used to determine proliferation and apoptosis. Western Blot and immunohistochemistry were used to analyze target protein expression (PTEN, PDCD4, Akt, p-Akt). We also constructed PC9R xenograft tumor model to observe the relationship between miR-21 and EGFR-TKI resistance in vivo and validated it in the clinical serum specimens of NSCLC patients treated with EGFR-TKI. RESULT MiR-21 was overexpressed in the EGFR-TKI resistant cell line PC9R relative to PC9. The level of miR-21 was reversely correlated with the expression of PTEN and PDCD4 and positive correlated with PI3K/Akt pathway. Inhibiting miR-21 with lentivirus vector induces apoptosis in PC9R cell line and inhibiting miR-21with ASO suppressed tumor growth in nude mice treated with EGFR-TKI. Furthermore, serum miR-21 expression in NSCLC patients treated with EGFR-TKI was significantly higher at the time of acquiring resistance than at baseline (p<0.01). CONCLUSION miR-21 is involved in acquired resistance of EGFR-TKI in NSCLC, which is mediated by down-regulating PTEN and PDCD4 and activating PI3K/Akt pathway.

High Discrepancy of Driver Mutations in Patients with NSCLC and Synchronous Multiple Lung Ground-Glass Nodules

Background: The aim of this study was to investigate the discordance rates of eight known driver mutations among multiple matched intrapulmonary ground-glass nodules (GGNs) in non–small-cell lung cancer (NSCLC) patients. Methods: Tumors from 35 patients with multiple lesions resected, including confirmed NSCLC and at least one GGN, were analyzed for mutations in EGFR, KRAS, HER2, BRAF, and PIK3CA together with fusions in ALK, ROS1, and RET. Results: From 35 patients, a total of 72 lesions (60 were GGNs) were analyzed. These included nine adenocarcinoma in situ, nine minimal invasive adenocarcinoma, and 54 invasive adenocarcinoma. Among them, 33 tumor lesions (45.8 %) were found harboring EGFR mutations: 13 tumors with exon 19 deletion, 18 with L858R on exon 21, and two with both exon 19 del and L858R mutation. There were 5 tumors (6.9 %) harboring EML4-ALK fusion, four HER2 mutations (5.6%), three KRAS mutations (4.2%), one ROS1 fusion and one BRAF mutation. When we used the matched tumors to determine the intertumor discrepancy, only six out of 30 patients harbored identical mutations. The discordance rate of driver mutations was 80% (24 of 30) in those patients harboring at least one of the detected driver mutations. The median disease-free survival was 41.2 months (95% confidence interval: 35.8–52.6 months) and the median overall survival was “still not reached” in this cohort. Conclusions: We found a high discrepancy of driver mutations among NSCLC patients with GGNs and a favorable prognosis after multiple lesions resection, which support surgical resection in this situation as a reasonable approach.

FGFR1 amplification in lung squamous cell carcinoma: A systematic review with meta-analysis

INTRODUCTION Current targeted therapy proves no effective outcomes in lung squamous cell carcinoma (SQCC). Recent studies suggested that FGFR1 would be promising. This systematic review elaborated FGFR1 amplification in lung SQCC. METHODS An electronic search was conducted on PubMed, EMBASE, Web of SCI, Google Scholar and Cochrane Library. Eligible studies regarding incidence of FGFR1 amplification in lung SQCC and correlation between FGFR1 amplification and clinicopathological features or survival were extracted and analyzed. RESULTS We identified 13 eligible studies with a total of 1798 patients. The results showed about 19% of FGFR1 amplification (95% CI: 0.15-0.24; I(2)=84.5%; p=0.000). Using the same test method: FISH, definition and ethnicity, the rates were 17% (95% CI: 0.14-0.20; I(2)=53.1%; p=0.037), 21% (95% CI: 0.18-0.24; I(2)=0; p=0.615), and 16% (95% CI: 0.13-0.19; I(2)=72.1%; p=0.028), respectively. Pearsons correlation analysis suggested that smoking status was highly correlated with FGFR1 amplification (coefficient=0.961, p<0.001). FGFR1 amplification was significantly correlated with lymph node metastasis (OR: 2.27; 95% CI: 1.62-3.20; p=0.000), but not correlated with gender (OR: 1.12; 95% CI: 0.90-1.38; p=0.91), differentiation (OR: 1.02; 95% CI: 0.76-1.38; p=0.959) and stage (OR: 0.93; 95% CI: 0.73-1.19; p=0.877) in lung SQCC patients. With respect to survival, FGFR1 amplification had no influence on PFS (HR: 1.57; 95% CI: 0.85-2.30; p=0.259) and OS (HR: 1.40; 95% CI: 0.90-1.89; p=0.416) for SQCC patients. CONCLUSION FGFR1 amplification is about 19%. Gender, stage, differentiation, ethnicities and test methods have no influence on FGFR1 amplification. FGFR1 amplification trends to correlate with lymph node metastasis and smoking. Whether FGFR1 amplification has effect on survival remains controversial.

T790M mutation is associated with better efficacy of treatment beyond progression with EGFR-TKI in advanced NSCLC patients

BACKGROUND AND PURPOSE Continuous EGFR-TKI treatment beyond progression has shown promising benefit for some patients with acquired resistance to EGFR-TKIs. The aim of this study was to investigate the association of secondary T790M mutation at the time of progression with the efficacy of EGFR-TKI treatment beyond progression. METHODS From March 2011 to March 2013, patients with advanced NSCLC who developed acquired resistance to EGFR-TKI and where a re-biopsy was performed at Tongji University Cancer Institute were included into this study. Scorpion ARMS was used to detect EGFR mutation status. RESULTS A total of 54 patients were enrolled in this study with a median progression-free survival time (PFS1) of 10.9 months according to RECIST criteria. In all, 53.7% (29/54) had T790M mutation after the failure of EGFR-TKIs; PFS1 was not statistically significantly different between patients with T790M mutation and without (13.0 vs. 10.5 months, p = 0.894). In all, 41 patients received TKI treatment beyond progression, including 22 with local progression to receive additional local therapy and 19 with gradual progression to receive additional chemotherapy. The median progression-free survival time (PFS2) of patients who received EGFR-TKI beyond progression treatment was 3.5 months (95% CI, 2.689-4.311). Patients with T790M mutation had significantly longer PFS2 (6.3 vs. 2.6 months, p = 0.002) and overall survival (39.8 vs. 23.2 months, p = 0.044) than those without. CONCLUSION Patients with secondary T790M mutation at the time of progression having gradual or local progression after acquired resistance to EGFR-TKI benefit more from EGFR-TKI treatment beyond progression compared to those without T790M mutation.

Association between Single Nucleotide Polymorphisms (SNPs) and Toxicity of Advanced Non-Small-Cell Lung Cancer Patients Treated with Chemotherapy

New therapeutic approaches are being developed based on the findings that several genetic abnormalities underlying non-small-cell lung cancer (NSCLC) could influence chemosensitivity. In this study, we assessed whether polymorphisms in genes of nucleotide excision repair (NER) pathway, including ERCC5, ERCC6, MMS19L, CCNH, XPC, RRM1, can affect the tolerability of platinum-based chemotherapy in NSCLC patients. We used AllGloTM probe to assess genotyping and polymorphisms in 388 stage IIIB and IV NSCLC patients treated with platinum-based chemotherapy. MMS19L might be associated with the adverse events of chemotherapy in NSCLC, especially for all grade leucopenia (P = 0.020), all grade jaundice (P = 0.037) and all grade creatinine increasing (P = 0.013). In terms of grade 3/4 adverse events, MMS19L was related with total grade 3/4 adverse events (P = 0.024) and grade 3/4 thrombocytopenia (P = 0.035), while RRM1 was related with total grade 3/4 adverse events (P = 0.047) and grade 3/4 vomiting (P = 0.046). ERCC5 was related with more infection (P = 0.017). We found that some SNPs in NER pathway genes were correlated with toxicity treated with double chemotherapy in advanced NSCLC patients, especially for SNPs of MMS19L, RRM1 and ERCC5.

The impact of clinical characteristics on outcomes from maintenance therapy in non-small cell lung cancer: A systematic review with meta-analysis.

OBJECTIVES Although maintenance therapy has been a routine treatment paradigm for advanced non-small cell lung cancer (NSCLC), there is currently lack of direct evidence to identify patients most likely to benefit from maintenance therapy for advanced NSCLC. MATERIALS AND METHODS Trials comparing maintenance therapy with placebo or observation in NSCLC were identified. The primary endpoint was overall survival (OS) in trial population and predefined subgroups. Other endpoints included progression-free survival (PFS) in trial population and predefined subgroups, toxicities and health-related quality of life (QoL). RESULTS 13 trials with 4960 patients were identified. Maintenance therapy yielded a statistically significant but clinically modest improvement in OS (hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.78-0.89, P<0.001), without significant difference between switch and continuation strategy (HR, 0.83 vs. 0.86; Pinteraction=0.631). Patients with performance status (PS) of 0 derived more PFS benefit (HR, 0.52; 95% CI, 0.45-0.61) than those with PS of 1 (HR, 0.69; 95% CI, 0.63-0.76; Pinteraction=0.002). Patients with adenocarcinoma derived more PFS benefit (HR, 0.54; 95% CI, 0.46-0.64) than those with squamous cell carcinoma (HR, 0.85; 95% CI, 0.68-1.06; Pinteraction=0.001). Patients with activating epidermal growth factor receptor (EGFR) mutations derived more survival benefit than those with wild-type EGFR tumors in terms of OS (HR, 0.53 vs. 0.85, Pinteraction=0.086) and PFS (HR, 0.20 vs. 0.80, Pinteraction=0.003). Response to first-line therapy did not significantly predict additional benefit from maintenance therapy. Toxicities occurred more frequently in patients treated with maintenance therapy but health-related QoL was not adversely affected by maintenance therapy. CONCLUSION Maintenance therapy with either a continuation or a switch strategy yields a statistically significant but clinically modest improvement in OS for patients with advanced NSCLC. Factors that may predict benefit from maintenance therapy (tumor histology, PS, or EGFR mutation status), as well as economic considerations should be taken into account before initiating maintenance therapy.

Epithelial phenotype as a predictive marker for response to EGFR-TKIs in non-small cell lung cancer patients with wild-type EGFR.

Epithelial‐to‐mesenchymal transition (EMT) has profound impacts on cancer progression and also on drug resistance, including epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‐TKIs). Nowadays, there is still no predictive biomarker identified for the use of EGFR‐TKIs in non‐small cell lung cancer (NSCLC) patients with wild‐type EGFR. To clarify the role of EMT phenotype as a predictive marker for EGFR‐TKI, we performed a retrospective study in 202 stage IV or recurrent NSCLC patients receiving gefitinib or erlotinib therapy from June 2008 to September 2012 in our institute. Clinical data and EGFR mutational status were collected, while epithelial, epithelial to mesenchymal, not specified or mesenchymal phenotype were classified according to EMT markers such as E‐cadherin, fibronectin, N‐cadherin and vimentin by immunohistochemistry. Epithelial phenotype was more frequently found in patients with EGFR mutation (p = 0.044). Epithelial phenotype was associated with a significantly higher objective response rate (23.5 vs. 11.1 vs. 0.0 vs. 2.4%, p = 0.011), longer progression‐free survival (4.4 vs. 1.9 vs. 1.7 vs. 1.0 months, p < 0.001) and longer overall survival (11.5 vs. 8.9 vs. 4.5 vs. 4.9 months, p < 0.001) compared to epithelial to mesenchymal, not specified and mesenchymal phenotype in the wild‐type EGFR subgroup. In the subgroup with EGFR mutation, the trend remained but without a statistically significant difference. In conclusion, epithelial phenotype was more likely expressed in patients with EGFR mutation and was associated with a better outcome in advanced NSCLC patients with wild‐type EGFR, which indicates that the EMT phenotype might be a potential marker to guide EGFR‐TKI therapy in this population.

Prognostic value of high EZH2 expression in patients with different types of cancer: a systematic review with meta-analysis

Enhancer of zeste homologue 2 (EZH2) is a potential independent mechanism for epigenetic silencing of tumor suppressor genes in cancer. We conducted an electronic search on PubMed, EMBASE, Web of Science, and Cochrane library to perform this up-to-date meta-analysis. Fifty-one studies with a total of 9444 patients were included. The prevalence of high EZH2 expression was 0.54 (95% CI: 0.47-0.61). High EZH2 expression was significantly associated with poorer prognosis [overall survival: HR 1.54 (95% CI: 1.30-1.78), P < 0.000; disease free survival: HR 1.35 (95% CI: 1.00-1.71), P < 0.000]. In breast cancer, high EZH2 expression correlated with histological types [OR: 1.53 (95CI: 1.13-2.06); P < 0.006], histological grade [OR: 1.62 (95CI: 1.35-1.95); P < 0.000], estrogen receptor (ER) negativity [OR: 2.05 (95CI: 1.67-2.52); P < 0.000], progesterone receptor (PgR) negativity [OR: 1.42 (95CI: 1.03-1.96); P = 0.034], HER-2 positivity [OR: 1.35 (95CI: 1.08-1.69); P = 0.009], and high p53 expression [OR: 1.66 (95CI: 1.07-2.59); P = 0.024]. These results suggest that high EZH2 expression may be a promising prognostic factor to different cancers. High EZH2 expression tends to correlate with pathological types, histological grade, ER negativity, PgR negativity, HER-2 positivity and p53 high expression in breast cancer.

Folate Receptor-Positive Circulating Tumor Cell Detected by LT-PCR-Based Method as a Diagnostic Biomarker for Non-Small-Cell Lung Cancer.

Introduction: To investigate the diagnostic performance of folate receptor–positive circulating tumor cells in distinguishing non–small-cell lung cancer (NSCLC) from lung benign disease by using a novel ligand-targeted polymerase chain reaction (PCR) detection technique. Methods: Circulating tumor cells were enriched from 3-ml peripheral blood by immunomagnetic depletion of leukocytes and then labeled with a conjugate of a tumor-specific ligand folic acid and a synthesized oligonucleotide. After washing off free conjugates, the stripped bound conjugates were analyzed by quantitative PCR. Results: Seven hundred fifty-six participants (473 patients with NSCLC, 227 patients with lung benign disease, and 56 healthy donors) were randomly assigned to a training set and a test set. The circulating tumor cell (CTC) levels in patients with NSCLC were significant higher than those with lung benign disease (p < 0.001) and healthy donors (p < 0.001). Compared with carcinoembryonic antigen, neuron-specific enolase, and Cyfra21-1, CTCs displayed the highest area under the receiver operating characteristic curve (training set, 0.815; validation set, 0.813) in the diagnosis of NSCLC, with a markedly sensitivity (training set, 72.46%; validation set, 76.37%) and specificity (training set, 88.65%; validation set, 82.39%). The model combining CTCs with carcinoembryonic antigen, neuron-specific enolase, and Cyfra21-1 was more effective for the diagnosis of NSCLC than tumor makers alone (sensitivity and specificity in the training set, 84.21% and 83.91%; validation set, 88.78% and 87.36%, respectively). In addition, the CTC levels were higher in patients with stage III/IV NSCLC compared with those with stage I/II disease. Conclusion: Ligand-targeted PCR technique was feasible and reliable for detecting folate receptor–positive CTCs in patients with NSCLC, and CTC levels could be used as a useful biomarker for the diagnosis of NSCLC.