Patrick Dorn

miR-29b Mediates NF-κB Signaling in KRAS-Induced Non–Small Cell Lung Cancers

A global understanding of miRNA function in EGFR signaling pathways may provide insights into improving the management of KRAS-mutant lung cancers, which remain relatively recalcitrant to treatment. To identify miRNAs implicated in EGFR signaling, we transduced bronchial epithelial BEAS-2B cells with retroviral vectors expressing KRAS(G12V) and monitored miRNA expression patterns by microarray analysis. Through this approach, we defined miR-29b as an important target for upregulation by mutant KRAS in non-small cell lung cancers. Cell biologic analyses showed that pharmacologic inhibition of EGFR or MEK was sufficient to reduce levels of miR-29b, while PI3K inhibition had no effect. In KRAS(G12V)-transduced BEAS-2B cells, introduction of anti-miR-29b constructs increased the sensitivity to apoptosis, arguing that miR-29b mediated apoptotic resistance conferred by mutant KRAS. Mechanistic investigations traced this effect to the ability of miR-29b to target TNFAIP3/A20, a negative regulator of NF-κB signaling. Accordingly, overexpression of an miR-29b-refractory isoform of TNFAIP3 restored NF-κB and extrinsic apoptosis, confirming that TNFAIP3 is a functionally relevant target of miR-29b. We also noted that miR-29b could confer sensitivity to intrinsic apoptosis triggered by exposure to cisplatin, a drug used widely in lung cancer treatment. Thus, miR-29b expression may tilt cells from extrinsic to intrinsic mechanisms of apoptosis. Overall, our results reveal a complexity in cancer for miR-29b, which can act as either an oncogene or tumor suppressor gene depending on signaling context. Cancer Res; 76(14); 4160-9. ©2016 AACR.

Blocking the epithelial-to-mesenchymal transition pathway abrogates resistance to anti-folate chemotherapy in lung cancer

Anticancer therapies currently used in the clinic often can neither eradicate the tumor nor prevent disease recurrence due to tumor resistance. In this study, we showed that chemoresistance to pemetrexed, a multi-target anti-folate (MTA) chemotherapeutic agent for non-small cell lung cancer (NSCLC), is associated with a stem cell-like phenotype characterized by an enriched stem cell gene signature, augmented aldehyde dehydrogenase activity and greater clonogenic potential. Mechanistically, chemoresistance to MTA requires activation of epithelial-to-mesenchymal transition (EMT) pathway in that an experimentally induced EMT per se promotes chemoresistance in NSCLC and inhibition of EMT signaling by kaempferol renders the otherwise chemoresistant cancer cells susceptible to MTA. Relevant to the clinical setting, human primary NSCLC cells with an elevated EMT signaling feature a significantly enhanced potential to resist MTA, whereas concomitant administration of kaempferol abrogates MTA chemoresistance, regardless of whether it is due to an intrinsic or induced activation of the EMT pathway. Collectively, our findings reveal that a bona fide activation of EMT pathway is required and sufficient for chemoresistance to MTA and that kaempferol potently regresses this chemotherapy refractory phenotype, highlighting the potential of EMT pathway inhibition to enhance chemotherapeutic response of lung cancer.

Influence of Comorbidity on Outcome after Pulmonary Resection in the Elderly

The aim of this study was to determine the influence of comorbidity on outcome after pulmonary resection in patients over 75 years old. Three hundred and thirty-three patients with non-small-cell lung cancer operated on between 1998 and 2002 were divided into 3 age groups: < 60 years (group 1), 60–75 years (group 2), > 75 years (group 3). Overall operative mortality was 0.3%; 30-day mortality was 1%. There were more major complications with re-operation in groups 1 and 2, but minor complications occurred significantly more frequently in group 3 (36% vs 16%). Overall mean hospital stay was 12 days, with no significant difference among groups. Three-year survival rates were: 80%, 70%, and 65% in groups 1, 2, and 3, respectively, with no significant difference among groups. Age or the presence of comorbidity should not be considered contraindications for lung resection. With proper patient selection and careful preoperative evaluation, many major complications after pneumonectomy are avoidable.

Increased PD-L1 expression and IL-6 secretion characterize human lung tumor-derived perivascular-like cells that promote vascular leakage in a perfusable microvasculature model.

Pericytes represent important support cells surrounding microvessels found in solid organs. Emerging evidence points to their involvement in tumor progression and metastasis. Although reported to be present in the human lung, their specific presence and functional orientation within the tumor microenvironment in non-small cell lung cancer (NSCLC) has not yet been adequately studied. Using a multiparameter approach, we prospectively identified, sorted and expanded mesenchymal cells from human primary NSCLC samples based on co-expression of CD73 and CD90 while lacking hematopoietic and endothelial lineage markers (CD45, CD31, CD14 and Gly-A) and the epithelial marker EpCAM. Compared to their normal counterpart, tumor-derived Lineage-EpCAM-CD73+CD90+ cells showed enhanced expression of the immunosuppressive ligand PD-L1, a higher constitutive secretion of IL-6 and increased basal αSMA levels. In an in vitro model of 3D microvessels, both tumor-derived and matched normal Lineage-EpCAM-CD73+CD90+ cells supported the assembly of perfusable vessels. However, tumor-derived Lineage-EpCAM-CD73+CD90+ cells led to the formation of vessels with significantly increased permeability. Together, our data show that perivascular-like cells present in NSCLC retain functional abnormalities in vitro. Perivascular-like cells as an eventual target in NSCLC warrants further investigation.

Video thoracoscopic surgery used to manage tuberculosis in thoracic surgery

BackgroundThe aim of this study was to evaluate the indications and results of video-assisted thoracic surgery (VATS) for the management of tuberculosis in 10 patients with unusual clinical and radiologic presentation for the disease.MethodsFrom March 2000 to March 2002, 96 diagnostic VATS operations for unclear thoracic lesions were performed at the authors’ institution. Their final diagnosis for 10 (10.4%) of these patients was tuberculosis. The suspected preoperative diagnoses were pancoast tumour (n = 1), pericardial effusion (n = 1), pleural mesothelioma (n = 1), pleural empyema (n = 2), mediastinal lymphoma (n = l), and lung cancer (n = 4).ResultsFor all the patients, the diagnosis of tuberculosis was achieved by VATS. The duration of drainage was 2.5 days. There have been neither morbidity nor mortality since surgery. The hospital stay was 3 to 5 days.ConclusionThoracoscopy is a safe and effective procedure for the management of tuberculosis. Tuberculosis should be kept in mind during the differential diagnosis of unknown thoracic lesions, and also for patients who live in economically well developed countries and are not immune compromised.

Inflammatory Myofibroblastic Tumor of the Trachea with Concomitant Granulomatous Lymph Node Lesions

We report herein the case of a 57-year-old lady who had two concomittant lesions, an inflammatory myofibroblastic tumor in the trachea, and severe granulomatous lesions in the adjacent hilar lymph nodes. While these two lesions shared histological and some immunohistochemical features lesions. They differed in terms of ALK-1 expression, which was positive in the tracheal tumor and negative in the lymph nodes. The discussion of the case circles around putative pathophysiological links between the lesions. The authors favor the idea that the lymph nodes present a sarcoid-like granulomatous reaction to the inflammatory myofibroblastic tumor in the trachea over a coexistence of two independent entities. However, no conclusive evidence for this interpretation can be presented based on the existing literature.

18P Epithelial-to-mesenchymal transition (EMT) is required for resistance to anti-folate chemotherapy in lung cancer.

cells. Prognoscan assessment identified decrease SASH1 mRNA expression lead to a prognostic reduction in patient survival. The depletion of SASH1 in lung cells resulted in a significant increase in cellular proliferation in cancer lung cells. Connectivity mapping predicted the drug Chloropyramine would lead to an increase in SASH1 expression. We demonstrated that Chloropyramine upregulates SASH1 in malignant cell lines. In keeping with this we have demonstrated that Chloropyramine inhibited lung cancer proliferation in vitro. These novel observations support the tumour suppressive role of SASH1 in lung tumourgenesis. Further work is ongoing to understand the function of SASH1 in lung cancer growth. Conclusions: The upregulation of SASH1, either by chemical agents or gene therapy, is a potential novel approach to the management of lung cancer and other solid tumours. Legal entity responsible for the study: Queensland University of Technology Funding: Queensland Health Disclosure: All authors have declared no conflicts of interest.

Upper lobe anterior segment (S3): technique of fissureless uniportal VATS segmentectomy

There is a growing interest for minimally invasive sublobar anatomic resections. Whereas some segmentectomies like lingulectomy or S6-resection appear trivial for experienced surgeons, other sublobar anatomic resections with large parenchymal surface remain challenging. In our video, we demonstrate our technique to separate a fused interlobar fissure between upper and middle lobe, safely allowing to proceed to S3-segmentectomy.

Outcomes from the Delphi process of the Thoracic Robotic Curriculum Development Committee.

OBJECTIVES As the adoption of robotic procedures becomes more widespread, additional risk related to the learning curve can be expected. This article reports the results of a Delphi process to define procedures to optimize robotic training of thoracic surgeons and to promote safe performance of established robotic interventions as, for example, lung cancer and thymoma surgery. METHODS In June 2016, a working panel was spontaneously created by members of the European Society of Thoracic Surgeons (ESTS) and European Association for Cardio-Thoracic Surgery (EACTS) with a specialist interest in robotic thoracic surgery and/or surgical training. An e-consensus-finding exercise using the Delphi methodology was applied requiring 80% agreement to reach consensus on each question. Repeated iterations of anonymous voting continued over 3 rounds. RESULTS Agreement was reached on many points: a standardized robotic training curriculum for robotic thoracic surgery should be divided into clearly defined sections as a staged learning pathway; the basic robotic curriculum should include a baseline evaluation, an e-learning module, a simulation-based training (including virtual reality simulation, Dry lab and Wet lab) and a robotic theatre (bedside) observation. Advanced robotic training should include e-learning on index procedures (right upper lobe) with video demonstration, access to video library of robotic procedures, simulation training, modular console training to index procedure, transition to full-procedure training with a proctor and final evaluation of the submitted video to certified independent examiners. CONCLUSIONS Agreement was reached on a large number of questions to optimize and standardize training and education of thoracic surgeons in robotic activity. The production of the content of the learning material is ongoing.

Minimally invasive resection and reconstruction of the intrathoracic trachea and carina

In their publication “Video-assisted thoracic surgery resection and reconstruction of carina and trachea for malignant or benign disease in 12 patients: three centers’ experience in China”, Li and co-authors very nicely presented their know-how and techniques of performing these complex procedures by video-assisted thoracoscopic surgery (VATS) (1). They clearly showed the feasibility and safety of VATS in the treatment of benign as well as malignant diseases of the carina and trachea.