A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer.

BACKGROUND: MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC). METHODS: Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs. RESULTS: Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues. CONCLUSION: The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.

Clinicopathologic and prognostic significance of c-MYC copy number gain in lung adenocarcinomas.

BACKGROUND: c-MYC copy number gain (c-MYC gain) has been associated with aggressive behaviour in several cancers. However, the role of c-MYC gain has not yet been determined in lung adenocarcinomas classified by genetic alterations in epidermal growth factor receptor (EGFR), KRAS, and anaplastic lymphoma kinase (ALK) genes. We investigated the clinicopathologic and prognostic significance of c-MYC gain for disease-free survival (DFS) and overall survival (OS) according to EGFR, KRAS, and ALK gene status and stages in lung adenocarcinomas. METHODS: In 255 adenocarcinomas resected in Seoul National University Bundang Hospital from 2003 to 2009, fluorescence in situ hybridisation (FISH) with c-MYC probe and centromeric enumeration probe 8 (CEP8) was analysed using tissue microarray containing single representative core per each case. EGFR (codon 18 to 21) and KRAS (codon 12, 13, and 61) mutations were analysed by polymerase chain reaction and direct sequencing method from formalin-fixed, paraffin-embedded tissue sections. ALK rearrangement was determined by FISH method. c-MYC gain was defined as >2 copies per nucleus, chromosome 8 gain as ⩾3 copies per nucleus, and gain of c-MYC:CEP8 ratio (hereafter, c-MYC amplification) as ⩾2. RESULTS: We observed c-MYC gain in 20% (51 out of 255), chromosome 8 gain in 5.5% (14 out of 255), c-MYC amplification in 2.4% (6 out of 255), EGFR mutation in 49.4% (118 out of 239), KRAS mutation in 5.7% (7 out of 123), and ALK rearrangement in 4.9% (10 out of 205) of lung adenocarcinomas. c-MYC gain was observed in 19% (22 out of 118) of patients with lung adenocarcinomas with an EGFR mutation, but not in any patients with a KRAS mutation, or an ALK rearrangement. c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor in the full cohort of lung adenocarcinoma (P=0.022, hazard ratio (HR)=1.71, 95% confidence interval (CI), 1.08-2.69 for DFS; P=0.032, HR=2.04, 95% CI, 1.06-3.91 for OS), as well as in stage I subgroup (P=0.023, HR=4.70, 95% CI, 1.24-17.78 for DFS; P=0.031, HR=4.65, 95% CI, 1.15-18.81 for OS), and in EGFR-mutant subgroup (P=0.022; HR=2.14; 95% CI, 1.11-4.10 for DFS). CONCLUSIONS: c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor for DFS and OS in lung adenocarcinomas, both in full cohort and stage I cancer, and possibly for DFS in EGFR-mutant adenocarcinomas. Additional studies are required to determine if patients with lung adenocarcinoma with c-MYC gain are candidates for additional first-line treatment to mitigate their increased risk for disease progression and death.

The fate of patients on the waiting list for lung transplantation in Korea.

Lung transplantation for end-stage lung disease results in prolonged actuarial survival and improved pulmonary function. However, the shortage of donor lungs has been a major limiting factor in transplantation. The purpose of this study was to analyze the waiting time and mortality rate for each disease entity. The medical records of all patients listed in The Korean Network for Organ Sharing (KONOS) from May 1996 to May 2011 were analyzed to identify waiting times and causes of death. During the study period, 146 patients (86 males and 60 females) of mean age of 46.6 years (range; 5 to 73 years) showed idiopathic pulmonary fibrosis (IPF; n = 61), chronic obstructive pulmonary disease (COPD; n = 19) or bronchiectasis (n = 15). Sixty-five patients (44.5%) underwent lung or heart-lung transplantation. Sixty-two patients (42.5%) expired during the waiting period, and 19 patients are still on the waiting list. The mortality rate while waiting was highest among patients with primary pulmonary hypertension (62.5%) followed by IPF (57.4%), and acute respiratory distress syndrome (ARDS) (55.6%). The mean time from diagnosis to registration in KONOS was 15.5 months among the expired and 13.2 months in the transplanted group (P = .455). The mean time on waiting list was 8.2 months in the expired group and 3.7 months in the transplanted group (P = .012). In the expired group, the mean survival time was significantly shorter among patients with ARDS (2.2 months, P = .004) compared to IPF (7.9 months), COPD (10.7 months), and primary pulmonary hypertension (PPH) (30.0 months). The high mortality rate (42.5%) during the waiting period in Korea may result from the lack of donors and the delay in registration.

Donor evaluation for lung transplantation in Korea.

Lung transplantation for end-stage lung disease results in prolonged survival and improved pulmonary function. However, the shortage of donor lungs has been a major limiting factor in Korea. We sought to investigate the number and utilization of donor lungs by the five institutions performing LTx in Korea, retrospectively reviewing outcomes of organs registered in the Korean Network for Organ Sharing from January to December, 2010. Lungs were offered from 270 brain-dead patients (189 males and 81 females) of mean age of 45.2 ± 14.2 years (range, 12 to 77 years). The most common cause of brain death was hemorrhage (n = 219, 81%). Only 18 (6.7%) donor lungs were used, which was low compared with kidney (93.3%), liver (86.3%), heart (26.7%), and pancreas (11.1%) use. The mean age of donors of transplanted lungs was 35.7 years (range, 14 to 51 years) compared with 45.9 years for other organs (P = .003). The characteristics of utilized donor lungs were: mean partial pressure of oxygen (PaO(2)), 300.9 mm Hg; mean smoking history, as 2.7 pack-years; and mean body mass index, 21.2 kg/m(2). The causes of refusal were medical ineligibility (n = 129) including poor PaO(2), abnormal chest x-ray, long smoking history, older age (n = 46), no properly matched recipient (n = 46), unknown (n = 17), and family withdrawal (n = 14). Only 8 (33.3%) were transplanted from standard criteria and 10 from the lungs that did not satisfy these criteria. An efficient utilization system is needed to improve lung transplantations.

Staple line covering procedure after thoracoscopic bullectomy for the management of primary spontaneous pneumothorax.

BACKGROUND: Thoracoscopic bullectomy together with a pleural adhesive procedure is generally accepted as the standard for the definitive treatment of primary spontaneous pneumothorax (PSP). The purpose of this study was to evaluate whether the results of a thoracoscopic bullectomy followed by coverage of the staple line with cellulose mesh and fibrin glue could be comparable with those of adhesive procedures described in the literature. METHODS: Between May 2000 and February 2003, we performed 227 thoracoscopic surgeries on 219 patients with PSP using a single technique. After the bullectomy, the staple line was covered with cellulose mesh and fibrin glue. The postoperative status was evaluated with a mean follow-up of 46 months. RESULTS: The mean patient age was 24.3 years and 90.9 % of the 219 patients were male. Recurrent pneumothorax (37.4 %) was the most common operative indication, followed by persistent air leakage of more than 5 days (28.2 %). The mean duration of postoperative chest tube drainage was 1.6 days and the mean postoperative hospital stay was 3.8 days. Six patients experienced surgical complications (2.2 %); there was air leakage of more than 3 days in two cases, a small apical dead space in one case, a fever-associated wound problem in one case, and a reoperation due to air leakage of more than 7 days in two cases. Eleven patients (4.8 %) suffered a recurrence of pneumothorax during the follow-up period. Of these, nine cases required readmission and three (1.3 %) of these cases required a reoperation. CONCLUSIONS: Given the nature of a meticulous thoracoscopic bullectomy followed by coverage with cellulose mesh and fibrin glue, good surgical results can be expected without the need for a pleural adhesive procedure.

Pulmonary preservation effect of nitroglycerine in isolated rat lung reperfusion model.

PURPOSE: Though nitric oxide has many favorable protective effects on donor lungs, it may also have cytotoxic side effects. In this regard, we investigated whether administration of nitroglycerine, a nitric oxide donor, could minimize ischemia-reperfusion injury in an isolated rat lung reperfusion model. MATERIALS AND METHODS: Thirty-five Sprague-Dawley rats were used for this experiment. The nitroglycerine (NTG) group (n = 18) received the drug intravenously and the 17 control group hosts were treated with the same amount of normal saline. The heart-lung block was retrieved, weighed, and maintained in University of Wisconsin solution for 24 hours at 10 degrees C. Reperfusion was performed using human blood diluted in Krebs-Hensleit solution for 60 minutes. Peak inspiratory pressure, pulmonary artery pressure, and blood gas analysis were performed. After 60 minutes of reperfusion, the amount of protein in bronchoalveolar lavage (BAL) fluid and the myeloperoxidase (MPO) activity in the lung were measured. RESULTS: There were no major statistical differences between the two groups in peak inspiratory pressure and pulmonary artery pressure, but the NTG group maintained lower pulmonary artery pressure during the whole period of reperfusion. Oxygen tension in the NTG group was significantly higher, whereas there were no differences in carbon dioxide tension, BAL fluid, protein, or MPO activity. CONCLUSION: Administration of NTG before donor lung preservation resulted in better lung protection, a possible strategy for clinical application.

Ultrastructural evaluation of the protective effect of nitroglycerin in preservation-reperfusion injury of rat lungs.

AIM OF STUDY: Nitric oxide (NO) has been reported as a favorable protective supplement in donor lung preservation, but related ultrastructural studies are rare in the literature. This study was performed to assess the ultrastructural changes and to evaluate the protective effect of NO as donor nitroglycerin (NTG) treatment of ischemia-reperfusion injury in rat lungs. MATERIALS AND METHODS: Fifteen Sprague-Dawley rats weighing 300 to 350 g were used in this study. The NTG group (n = 5) used intravenous administration followed by mixture in the University of Wisconsin (UW) solution. For the non-NTG group (n = 5), we injected the same amount of normal saline intravenously followed by admixture in the UW solution. The heart-lung blocks were removed, weighed, and kept in UW solution for 24 hours at 10 degrees C. Reperfusion using human blood diluted in Krebs-Hensleit solution was done for 60 minutes. For the control group (n = 5), we injected the same amount of normal saline intravenously, and removed the lungs with no preservation and reperfusion procedures. RESULTS: The non-NTG group showed multiple patchy areas of alveolar collapse with marked swelling and destruction of type I epithelial cells, loss of type II cell surfactant granules, endothelial swelling and papillary projection, interstitial edema, and alveolar macrophages with active phagocytosis of the destroyed materials. The NTG group showed similar ultrastructural changes, but in a lesser severity compared with the non-NTG group. CONCLUSION: Administration of the NTG reduced the ischemia-reperfusion injury in the rat donor lungs. Ultrastructural examination was an effective tool to evaluate the protective effect of NTG in ischemia-reperfusion procedures of donor lungs.