Purpose: The resistance to the EGFR tyrosine kinase inhibitors (TKI) is a major concern in non-small cell lung cancer (NSCLC) treatment. T790M mutation in EGFR accounts for nearly 50% of the acquired resistance to EGFR-TKIs. Earlier studies suggested that T790M mutation was also detected in TKI-na€ ve NSCLCs in a small cohort. Here, we use an ultra-sensitive droplet digital PCR (ddPCR) technique to address the incidence and clinical significance of pretreatment T790M in a larger cohort.Experimental Design: ddPCR was established as follows: wildtype or T790M mutation-containing DNA fragments were cloned into plasmids. Candidate threshold was identified using wild-type plasmid, normal human genomic DNA, and human A549 cell line DNA, which expresses wild type. Surgically resected tumor tissues from 373 NSCLC patients with EGFR-activating mutations were then examined for the presence of T790M using ddPCR.Results: Our data revealed a linear performance for this ddPCR method (R 2 ¼ 0.998) with an analytical sensitivity of approximately 0.001%. The overall incidence of the pretreatment T790M mutation was 79.9% (298/373), and the frequency ranged from 0.009% to 26.9%. The T790M mutation was detected more frequently in patients with a larger tumor size (P ¼ 0.019) and those with common EGFRactivating mutations (P ¼ 0.022), as compared with the others.Conclusions: The ultra-sensitive ddPCR assay revealed that pretreatment T790M was found in the majority of NSCLC patients with EGFR-activating mutations. ddPCR should be utilized for detailed assessment of the impact of the low frequency pretreatment T790M mutation on treatment with EGFR-TKIs. Clin Cancer Res; 21(15); 3552-60. Ó2015 AACR.

Collectively, STXBP1 aberrations can account for about one-third individuals with EIEE (14 of 43). These genetic and biologic data clearly showed that haploinsufficiency of STXBP1 is the important cause for cryptogenic EIEE.

Our data suggest that expression of PD-L1 protein is upregulated by the simultaneous amplification of the PD-L1 and JAK2 genes through JAK-STAT signaling in NCSLC.

No abstract

Cancer immunotherapy has shown promising results when combined with chemotherapy. Blocking CTLA-4 signaling by monoclonal antibody between cycles of chemotherapy may inhibit cancer cell repopulation and enhance the antitumoral immune reaction, thus improve the efficacy of chemotherapy in mesothelioma. The impact of CTLA-4 blockade on the early stage of tumor development was evaluated in a subcutaneous murine mesothelioma model. CTLA-4 blocking antibody was administered following each cycle of chemotherapy, and monotherapy was included as controls. Antitumor effect was evaluated by tumor growth delay and survival of the animals. Tumor cell repopulation was quantified by bromodeoxyuridine incorporation and Ki67 by immunohistochemistry and/or flow cytometry. In vitro cell killing was determined by classic chromium-released assay, and reverse transcription PCR (RT-PCR) was carried out to determine the gene expression of associated cytokines. Anti-CTLA-4 monoclonal antibody was able to inhibit tumor growth at early stage of tumor development. Antitumor effect was achieved by administration of CTLA-4 blockade between cycles of chemotherapy. Tumor cell repopulation during the intervals of cisplatin was inhibited by CTLA-4 blockade. Anti-CTLA-4 therapy gave rise to an increased number of CD4 and CD8 T cells infiltrating the tumor. RT-PCR showed that the gene expression of interleukin IL-2, IFN-g, granzyme B, and perforin increased in the tumor milieu. Blockade of CTLA-4 signaling showed effective anticancer effect, correlating with inhibiting cancer cell repopulation between cycles of chemotherapy and upregulating tumor-infiltrating T lymphocytes, cytokines, and cytolytic enzymes in a murine mesothelioma model.

Background: Elastography is a relatively new technology that can generate images reflective of tissue stiffness (elasticity). Neoplastic tissue is usually stiffer than normal structures. Objectives: The aim of this study was to evaluate the feasibility and utility of elastography when combined with convex-probe endobronchial ultrasound (CP-EBUS) for predicting and localizing metastatic lymph nodes during endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA). Methods: Consecutive results of endobronchial elastography of lymph nodes performed using EBUS- TBNA were prospectively collected and retrospectively analyzed. Elastography images were acquired as JPEG images and also recorded as video clips. Stiff area ratios [(stiff areas as blue pixels) / (lymph node areas as region of interest pixels)] for each lymph node determined by elastography were collated with the results of pathological diagnosis. We also performed elastography of surgically resected lymph nodes and compared image findings with pathological sections. Results: We evaluated 49 lymph nodes in 21 patients by CP-EBUS. There were 16 metastatic nodes (10 lung cancer metastases and 6 metastases from extrathoracic malignancies). Mean stiff area ratios were significantly greater for metastatic lymph nodes (0.478) than for benign nodes (0.216; p = 0.0002). Using a cutoff value of 0.311 for stiff area ratios, the sensitivity and specificity for predicting metastatic disease were 0.81 and 0.85, respectively. The stiff area was histologically compatible with metastatic distribution in surgically resected lymph nodes. Conclusions: Endobronchial elastography is feasible for lymph nodes when combined with CP-EBUS. Stiff area ratios are useful for predicting metastatic lymph nodes, which may be an efficient guide for TBNA.

The mutational spectrum is associated with smoking, body mass index, and other environmental factors, as well as with ERβ expression. Little association was observed between HPV and NSCLC.

No abstract