Xiaomin Niu

GPC5 rs2352028 Polymorphism and Risk of Lung Cancer in Han Chinese

rs2352028 in GPC5 has been reported to be associated with the risk of lung cancer in never-smokers. We performed a replication study in 1,045 lung cancer patients and 1,094 controls of Han Chinese origin. We found no association between rs2352028 and lung cancer/adenocarcinoma in never-smokers, but a p value of .04 (under the recessive model) was obtained between this SNP and overall lung cancer/adenocarcinoma. Our data and a recent meta-analysis suspected the possibility of rs2352028 being a risk variant of lung cancer risk in never-smokers. Our findings suggested that rs2352028 might confer a slight risk to lung cancer/adenocarcinoma.

The Hippo/YAP1 pathway interacts with FGFR1 signaling to maintain stemness in lung cancer

The Hippo pathway plays a critical role in organ size control, tissue homeostasis and tumor genesis through its key transcription regulator Yes-associated protein1 (YAP1), but the mechanism underlying its role in lung cancer is unclear. We hypothesized that YAP1 influences FGFR1 signaling to maintain cancer stem-like cell (CSC) properties in FGFR1-amplified lung cancer. In support of this, our data confirms that expression levels of YAP1 are positively associated with those of FGFR1 in clinical lung carcinoma samples as measured by real-time PCR, western blot, and immunohistochemistry (IHC) staining. Mechanistically, YAP1 up-regulates FGFR1 expression at the level of promoter through the TEAD binding site while bFGF/FGFR1 induces YAP1 expression via large tumor suppressors 1(LATS1). In addition, the absence of YAP1 abolishes self-renewal ability in lung cancer. Furthermore, an orthotropic mouse model highlights the function of YAP1 in the initiation and metastasis of lung cancer. Verteporfin, a YAP1 inhibitor, effectively inhibits both YAP1 and FGFR1 expression in lung cancer. Thus, we conclude that YAP1 is a potential therapeutic target for lung cancer. Combined targeting of YAP1 and FGFR1 may provide benefits to patients with FGFR1-amplified lung cancer.

FGFR1-ERK1/2-SOX2 axis promotes cell proliferation, epithelial–mesenchymal transition, and metastasis in FGFR1-amplified lung cancer

Epithelial–mesenchymal transition (EMT) is an important process for cancer metastasis, drug resistance, and cancer stem cells. Activation of fibroblast growth factor receptor 1 (FGFR1) was found to promote EMT and metastasis in prostate and breast cancers, but the effects and mechanisms in lung cancer was unclear. In this study, we aimed to explore whether and how activation of FGFR1 promotes EMT and metastasis in FGFR1-amplified lung cancer. We show that activation of FGFR1 by its ligand fibroblast growth factor 2 (FGF2) promoted proliferation, EMT, migration, and invasion in FGFR1-amplified lung cancer cell lines H1581 and DMS114, whereas inhibition of FGFR1 suppressed these processes. FGFR1 activation upregulated expression of Sry-related HMG box 2 (SOX2) by downstream phosphorylated ERK1/2; moreover, the upregulation of SOX2 by autophosphorylation variant ERK2_R67S plasmid transfection was not suppressed by FGFR1 inhibitor AZD4547 or MEK/ERK inhibitor AZD6244 in vitro. And SOX2 expression was also significantly upregulated in ERK2_R67S lentivirus-transfected stable cell lines in vivo. Overexpression of SOX2 promoted cell proliferation, EMT, migration, and invasion. Importantly, activation of FGFR1 could not promote these processes in SOX2-silenced stable cell lines. In orthotopic and subcutaneous lung cancer xenograft models, inhibition of FGFR1 suppressed tumor growth, SOX2 expression, EMT, and metastasis in vivo; however, these processes caused by SOX2-overexpressing stable cell lines were not suppressed by FGFR1 inhibition. Higher expression of FGFR1 and SOX2 were positively correlated, and both were associated with shorter survival in lung cancer patients. In conclusion, our findings reveal that activation of FGFR1 promotes cell proliferation, EMT, and metastasis by the newly defined FGFR1-ERK1/2-SOX2 axis in FGFR1-amplified lung cancer.

Genome-wide DNA Methylation Analysis Reveals GABBR2 as a Novel Epigenetic Target for EGFR 19 Deletion Lung Adenocarcinoma with Induction Erlotinib Treatment.

Purpose: The past decade has witnessed the rapid development of personalized targeted therapies in lung cancer. It is still unclear whether epigenetic changes are involved in the response to tyrosine kinase inhibitor (TKI) treatment in epidermal growth factor receptor (EGFR)-mutated lung cancer. Experimental Design: Methyl-sensitive cut counting sequencing (MSCC) was applied to investigate the methylation changes in paired tissues before and after erlotinib treatment for 42 days with partial response (PR) from stage IIIa (N2) lung adenocarcinoma patients (N = 2) with EGFR 19 deletion. The Sequenom EpiTYPER assay was used to validate the changed methylated candidate genes. Up- or downregulation of the candidate gene was performed to elucidate the potential mechanism in the regulation of erlotinib treatment response. Results: Sixty aberrant methylated genes were screened using MSCC sequencing. Two aberrant methylated genes, CBFA2T3 and GABBR2, were clearly validated. A same differential methylated region (DMR) between exon 2 and exon 3 of GABBR2 gene was confirmed consistently in both patients. GABBR2 was significantly downregulated in EGFR 19 deletion cells, HCC4006 and HCC827, but remained conserved in EGFR wild-type A549 cells after erlotinib treatment. Upregulation of GABBR2 expression significantly rescued erlotinib-induced apoptosis in HCC827 cells. GABBR2 was significantly downregulated, along with the reduction of S6, p-p70 S6, and p-ERK1/2, demonstrating that GABBR2 may play an important role in EGFR signaling through the ERK1/2 pathway. Conclusions: We demonstrated that GABBR2 gene might be a novel potential epigenetic treatment target with induction erlotinib treatment for stage IIIa (N2) EGFR 19 deletion lung adenocarcinoma. Clin Cancer Res; 23(17); 5003–14. ©2017 AACR.

Next generation sequencing reveals a novel ALK G1128A mutation resistant to crizotinib in an ALK-Rearranged NSCLC patient

OBJECTIVE Acquired secondary mutations in the anaplastic lymphoma kinase (ALK) gene have been identified in ALK-rearranged non-small cell lung cancer (NSCLC) patients who are resistant to treatment with the ALK inhibitor crizotinib. We sought to uncover novel mutations that contribute to resistance in these patients. MATERIALS AND METHODS Following clinical diagnosis and development of crizotinib treatment resistance, tissue and ctDNA samples were obtained from the 60-year-old patient and subjected to next-generation sequencing for identification of mutations contributing to drug resistance. RESULTS We identified a novel acquired NSCLC ALK G1128A mutation in the ALK + NSCLC patient who progressed on crizotinib after a short partial response to the drug. This mutation, ALK G1128A, is located at the glycine loop (the P-loop) of the ALK tyrosine kinase domain. As a gain-of-function mutation, ALK G1128A increases kinase activity and transformation ability, perhaps conferring resistance to crizotinib. CONCLUSIONS This case further illustrates the importance of comprehensive genomic profiling of resistant tumors for tailoring treatment decisions after disease progression on crizotinib in ALK + NSCLC in the era of rapidly developing new-generation ALK inhibitors and other therapeutic strategies.

TGFβ1 gene polymorphisms with the risk of radiation pneumonitis in non-small cell lung cancer in different ethnic study.

10606 Background: To investigate whether non-small-cell lung cancer (NSCLC) patients in Chinese with risk of radiation pneumonitis (RP) (grade≥3) by radiotherapy display reliable single nucleotide polymorphisms (SNPs) marker(s) located in transforming growth factor 1 (TGFβ1) gene. METHODS DNA was isolated from blood samples obtained from NSCLC patients (n=167) treated with definitive radiotherapy alone (n=125) or concurrent chemoradiation (n=42). Eight SNPs of the TGFβ1 gene (rs1800469, rs1800471, rs1982073, rs4803455, rs11466345, rs12983047, rs10417924, and rs10980942) were genotyped by direct DNA sequencing method. Kaplan-Meier cumulative probability was used to assess the risk of grade≥3 RP and Cox proportional hazards analysis to evaluate the effect of TGFβ1 genotypes on such risk. RESULTS There were 125 men and 42 women in the study with median age of 58 years. 53 (31.7%) patients developed grade 2 RP, 46 (27.5%) developed grade≥3 RP, respectively, based on CTCAEv3.0. SNP rs1982073 with RP risk in Caucasians was failed to validate to associate with the risk of grade≥3 RP in Chinese NSCLC patients. Multivariate analysis found AG/GG genotypes of novel TGFβ1 rs11466345 to be associated with a statistically significantly higher risk of RP grades≥3 (HR=2.295; 95% CI, 1.101 to 4.783; P=0.027), compared with the AA genotype, after adjustment for age, smoking status, and dosimetric parameters. CONCLUSIONS Our results showed that AG/GG genotypes of novel TGFβ1 rs11466345 were associated with higher risk of RP in Chinese NSCLC patients treated with radiotherapy. Further studies are warranted to confirm these findings in different ethnic populations.