Targeting lactate dehydrogenase B-dependent mitochondrial metabolism affects tumor initiating cells and inhibits tumorigenesis of non-small cell lung cancer by inducing mtDNA damage.

Once considered a waste product of anaerobic cellular metabolism, lactate has been identified as a critical regulator of tumorigenesis, maintenance, and progression. The putative primary function of lactate dehydrogenase B (LDHB) is to catalyze the conversion of lactate to pyruvate; however, its role in regulating metabolism during tumorigenesis is largely unknown. To determine whether LDHB plays a pivotal role in tumorigenesis, we performed 2D and 3D in vitro experiments, utilized a conventional xenograft tumor model, and developed a novel genetically engineered mouse model (GEMM) of non-small cell lung cancer (NSCLC), in which we combined an LDHB deletion allele with an inducible model of lung adenocarcinoma driven by the concomitant loss of p53 (also known as Trp53) and expression of oncogenic KRAS (G12D) (KP). Here, we show that epithelial-like, tumor-initiating NSCLC cells feature oxidative phosphorylation (OXPHOS) phenotype that is regulated by LDHB-mediated lactate metabolism. We show that silencing of LDHB induces persistent mitochondrial DNA damage, decreases mitochondrial respiratory complex activity and OXPHOS, resulting in reduced levels of mitochondria-dependent metabolites, e.g., TCA intermediates, amino acids, and nucleotides. Inhibition of LDHB dramatically reduced the survival of tumor-initiating cells and sphere formation in vitro, which can be partially restored by nucleotide supplementation. In addition, LDHB silencing reduced tumor initiation and growth of xenograft tumors. Furthermore, we report for the first time that homozygous deletion of LDHB significantly reduced lung tumorigenesis upon the concomitant loss of Tp53 and expression of oncogenic KRAS without considerably affecting the animal's health status, thereby identifying LDHB as a potential target for NSCLC therapy. In conclusion, our study shows for the first time that LDHB is essential for the maintenance of mitochondrial metabolism, especially nucleotide metabolism, demonstrating that LDHB is crucial for the survival and proliferation of NSCLC tumor-initiating cells and tumorigenesis.

Schedule-Dependent Treatment Increases Chemotherapy Efficacy in Malignant Pleural Mesothelioma.

Malignant pleural mesothelioma (MPM) is a rare but aggressive thoracic malignancy with limited treatment options. One of the standard treatments for MPM is chemotherapy, which consists of concurrent treatment with pemetrexed and cisplatin. Pemetrexed limits tumor growth by inhibiting critical metabolic enzymes involved in nucleotide synthesis. Cisplatin causes direct DNA damage, such as intra-strand and inter-strand cross-links, which are repaired by the nucleotide excision repair pathway, which depends on relatively high nucleotide levels. We hypothesized that prolonged pretreatment with pemetrexed might deplete nucleotide pools, thereby sensitizing cancer cells to subsequent cisplatin treatment. The MPM cell lines ACC-MESO-1 and NCI-H28 were treated for 72 h with pemetrexed. Three treatment schedules were evaluated by initiating 24 h of cisplatin treatment at 0 h (concomitant), 24 h, and 48 h relative to pemetrexed treatment, resulting in either concomitant administration or pemetrexed pretreatment for 24 h or 48 h, respectively. Multicolor flow cytometry was performed to detect γH2AX (phosphorylation of histone H2AX), a surrogate marker for the activation of the DNA damage response pathway. DAPI staining of DNA was used to analyze cell cycle distribution. Forward and side scatter intensity was used to distinguish subpopulations based on cellular size and granularity, respectively. Our study revealed that prolonged pemetrexed pretreatment for 48 h prior to cisplatin significantly reduced long-term cell growth. Specifically, pretreatment for 48 h with pemetrexed induced a cell cycle arrest, mainly in the G2/M phase, accumulation of persistent DNA damage, and induction of a senescence phenotype. The present study demonstrates that optimizing the treatment schedule by pretreatment with pemetrexed increases the efficacy of the pemetrexed-cisplatin combination therapy in MPM. We show that the observed benefits are associated with the persistence of treatment-induced DNA damage. Our study suggests that an adjustment of the treatment schedule could improve the efficacy of the standard chemotherapy regimen for MPM and might improve patient outcomes.

CD44 and its ligand hyaluronan as potential biomarkers in malignant pleural mesothelioma: evidence and perspectives.

Malignant pleural mesothelioma (MPM) is a rare and highly drug resistant tumor arising from the mesothelial surfaces of the lung pleura. The standard method to confirm MPM is the tedious, time-consuming cytological examination of cancer biopsy. Biomarkers that are detectable in pleural effusion or patient serum are reasonable options to provide a faster and noninvasive diagnostic approach. As yet, the current biomarkers for MPM lack specificity and sensitivity to discriminate this neoplasm from other lung tumors. CD44, a multifunctional surface receptor has been implicated in tumor progression in different cancers including MPM. The interaction of CD44 with its ligand, hyaluronan (HA) has demonstrated an important role in modulating cell proliferation and invasiveness in MPM. In particular, the high expression levels of these molecules have shown diagnostic relevance in MPM. This review will summarize the biology and diagnostic implication of CD44 and HA as well as the interaction of both molecules in MPM that will demonstrate their potential as biomarkers. Augmentation of the current markers in MPM may lead to an earlier diagnosis and management of this disease.

Schedule-dependent increased efficiency of pemetrexed-ionizing radiation combination therapy elicits a differential DNA damage response in lung cancer cells.

BACKGROUND: Lung cancer causes the most cancer deaths worldwide, thus there is a urgent need to develop new treatment options. Concurrent chemoradiotherapy has become a common strategy for the treatment of non-resectable solid tumors including non-small cell lung cancer. Pemetrexed is a folic acid antagonist that inhibits the synthesis of precursor nucleotides, whereas ionizing radiation induces DNA damage, the repair of which is dependent on sufficiently high nucleotide levels. In the clinical setting, the pemetrexed-ionizing radiation combination therapy is administered concomitantly. We hypothesized that prolonged pretreatment with pemetrexed could be beneficial, as prior depletion of nucleotide pools could sensitize cancer cells to subsequent irradiation. METHODS: Non-small cell lung cancer A549 cells were treated with 1 µM pemetrexed for 72 h. In addition, cells were exposed to five gray ionizing radiation either 1, 48 or 71 h after the initiation of the pemetrexed treatment. Cell growth, senescence induction, cell cycle distribution and DNA damage marker accumulation were analysed at different time points during the treatment and the recovery phase. RESULTS: Stand-alone treatments of five gray ionizing radiation and 1 µM pemetrexed resulted in an intermediate cell growth inhibition of A549 cells and were therefore applied as the combination regimen. Prolonged pemetrexed pretreatment for 71 h resulted in a significant S-phase accumulation. Irradiation and prolonged pemetrexed pretreatment maximally delayed long term cell growth. Additionally, senescence was augmented and recovery from treatment-induced DNA damage was most prominently delayed by prolonged pemetrexed pretreatment. CONCLUSIONS: Pretreatment with pemetrexed increases anticancer efficiency of pemetrexed-ionizing radiation combination therapy, which correlates with a persistence of treatment-induced DNA damage. Therefore, this study warrants further investigations to elucidate whether a similar adaptation to the standard treatment regimen could enhance the effectiveness of the non-small cell lung cancer clinical treatment regimen.

Prolonged pemetrexed pretreatment augments persistence of cisplatin-induced DNA damage and eliminates resistant lung cancer stem-like cells associated with EMT.

BACKGROUND: Lung cancer is the leading cause of cancer-related mortality, and new therapeutic options are urgently needed. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers, with the current standard regimen of care for NSCLC including chemotherapy with pemetrexed as a single agent or in combination with platinum-based agents, e.g. cisplatin. Pemetrexed is a folic acid antagonist that inhibits the synthesis of precursor nucleotides, whereas cisplatin directly induces DNA adducts, the repair of which is dependent on sufficiently high nucleotide levels. In the clinical setting, the pemetrexed-cisplatin combination therapy is administered concomitantly. We hypothesized that prolonged pretreatment with pemetrexed could be beneficial, as prior depletion of nucleotide pools could sensitize cancer cells to subsequent treatment with cisplatin. METHODS: NSCLC A549 and H460 cells were treated with pemetrexed for 72 h. In addition, 24 h of cisplatin treatment was initiated at day 1, 2 or 3 resulting in either simultaneous pemetrexed application or pemetrexed pretreatment for 24 or 48 h, respectively. Cell growth and colony formation as well as senescence induction were quantified after treatment. Cell cycle distribution and phosphorylation of histone variant H2AX as a surrogate marker for DNA damage was quantified by flow cytometry. Relative changes in gene expression were determined by quantitative real time PCR. RESULTS: Prolonged pemetrexed pretreatment for 48 h prior to cisplatin treatment maximally delayed long-term cell growth and significantly reduced the number of recovering clones. Moreover, apoptosis and senescence were augmented and recovery from treatment-induced DNA damage was delayed. Interestingly, a cell population was identified that displayed an epithelial-to-mesenchymal transition (EMT) and which had a stem cell phenotype. This population was highly resistant to concomitant pemetrexed-cisplatin treatment but was sensitized by pemetrexed pretreatment. CONCLUSIONS: Adaptation of the standard treatment schedule to include pretreatment with pemetrexed optimizes the anticancer efficiency of pemetrexed-cisplatin combination therapy, which correlates with a persistence of treatment-induced DNA damage. Therefore, this study warrants further investigations to elucidate whether such an adaptation could enhance the effectiveness of the standard clinical treatment regimen. In addition, a subpopulation of therapy resistant cells with EMT and cancer stem cell features was identified that was resistant to the standard treatment regimen but sensitive to pemetrexed pretreatment combined with cisplatin.

Influence of natural killer cells and perforin­mediated cytolysis on the development of chemically induced lung cancer in A/J mice.

One alternative approach for the treatment of lung cancer might be the activation of the immune system using vaccination strategies. However, most of clinical vaccination trials for lung cancer did not reach their primary end points, suggesting that lung cancer is of low immunogenicity. To provide additional experimental information about this important issue, we investigated which type of immune cells contributes to the protection from lung cancer development. Therefore, A/J mice induced for lung adenomas/ adenocarcinomas by the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) were depleted of CD4+ or CD8+ T cells, CD11b+ macrophages, Gr-1+ neutrophils and asialo GM1+ natural killer (NK) cells. Subsequent analysis of tumour growth showed an increase in tumour number only in mice depleted of NK cells. Further asking by which mechanism NK cells suppressed tumour development, we neutralized several death ligands of the tumour necrosis factor (TNF) family known to be involved in NK cell-mediated cytotoxicity. However neither depletion of TNF-α, TNF-related apoptosis-inducing ligand, TNF-like weak inducer of apoptosis or FasL alone nor in combination induced an augmentation of tumour burden. To show whether an alternative cell death pathway is involved, we next generated A/J mice deficient for perforin. After challenging with NNK, mice deficient for perforin showed an increase in tumour number and volume compared to wild-type A/J mice. In summary, our data suggest that NK cells and perforin-mediated cytolysis are critically involved in the protection from lung cancer giving promise for further immunotherapeutic strategies for this disease.

Cisplatin-resistant cells in malignant pleural mesothelioma cell lines show ALDH(high)CD44(+) phenotype and sphere-forming capacity.

BACKGROUND: Conventional chemotherapy in malignant pleural mesothelioma (MPM) has minimal impact on patient survival due to the supposed chemoresistance of cancer stem cells (CSCs). We sought to identify a sub-population of chemoresistant cells by using putative CSC markers, aldehyde dehydrogenase (ALDH) and CD44 in three MPM cell lines; H28, H2052 and Meso4. METHODS: The Aldefluor assay was used to measure ALDH activity and sort ALDH(high) and ALDH(low) cells. Drug-resistance was evaluated by cell viability, anchorage-independent sphere formation, flow-cytometry and qRT-PCR analyses. RESULTS: The ALDH(high) - and ALDH(low) -sorted fractions were able to demonstrate phenotypic heterogeneity and generate spheres, the latter being less efficient, and both showed an association with CD44. Cis- diamminedichloroplatinum (II) (cisplatin) treatment failed to reduce ALDH activity and conferred only a short-term inhibition of sphere generation in both ALDH(high) and ALDH(low) fractions of the three MPM cell lines. Induction of drug sensitivity by an ALDH inhibitor, diethylaminobenzaldehyde (DEAB) resulted in significant reductions in cell viability but not a complete elimination of the sphere-forming cells, suggestive of the presence of a drug-resistant subpopulation. At the transcript level, the cisplatin + DEAB-resistant cells showed upregulated mRNA expression levels for ALDH1A2, ALDH1A3 isozymes and CD44 indicating the involvement of these markers in conferring chemoresistance in both ALDH(high) and ALDH(low) fractions of the three MPM cell lines. CONCLUSIONS: Our study shows that ALDH(high) CD44(+) cells are implicated in conveying tolerance to cisplatin in the three MPM cell lines. The combined use of CD44 and ALDH widens the window for identification and targeting of a drug-resistant population which may improve the current treatment modalities in mesothelioma.

Prolonged amelioration of acute lung allograft rejection by sequential overexpression of human interleukin-10 and hepatocyte growth factor in rats.

The effect of prolonged electroporation-mediated human interleukin-10 (hIL-10) overexpression 24 hours before transplantation, combined with sequential human hepatocyte growth factor (HGF) overexpression into skeletal muscle on day 5, on rat lung allograft rejection was evaluated. Left lung allotransplantation was performed from Brown-Norway to Fischer-F344 rats. Gene transfer into skeletal muscle was enhanced by electroporation. Three groups were studied: group I animals (n = 5) received 2.5 µg pCIK-hIL-10 (hIL-10/CMV [cytomegalovirus] early promoter enhancer) on day -1 and 80 µg pCIK-HGF (HGF/CMV early promoter enhancer) on day 5. Group II animals (n = 4) received 2.5 µg pCIK-hIL-10 and pUbC-hIL-10 (hIL-10/pUbC promoter) on day -1. Control group III animals (n = 4) were treated by sham electroporation on days -1 and 5. All animals received daily nontherapeutic intraperitoneal dose of cyclosporin A (2.5 mg/kg) and were sacrificed on day 15. Graft oxygenation and allograft rejection were evaluated. Significant differences were found between study groups in graft oxygenation (Pao(2)) (P = .0028; group I vs. groups II and III, P < .01 each). Pao(2) was low in group II (31 ± 1 mm Hg) and in group III controls (34 ± 10 mm Hg), without statistically significant difference between these 2 groups (P = .54). In contrast, in group I, Pao(2) of recipients sequentially transduced with IL-10 and HGF plasmids was much improved, with 112 ± 39 mm Hg (vs. groups II and III; P < .01 each), paralleled by reduced vascular and bronchial rejection (group I vs. groups II and III, P < .021 each). Sequential overexpression of anti-inflammatory cytokine IL-10, followed by sequential and overlapping HGF overexpression on day 5, preserves lung function and reduces acute lung allograft rejection up to day 15 post transplant as compared to prolonged IL-10 overexpression alone.

A prognostic and predictive computational pathology image signature for added benefit of adjuvant chemotherapy in early stage non-small-cell lung cancer.

BACKGROUND: We developed and validated a prognostic and predictive computational pathology risk score (CoRiS) using H&E stained tissue images from patients with early-stage non-small cell lung cancer (ES-NSCLC). METHODS: 1330 patients with ES-NSCLC were acquired from 3 independent sources and divided into four cohorts D1-4. D1 comprised 100 surgery treated patients and was used to identify prognostic features via an elastic-net Cox model to predict overall and disease-free survival. CoRiS was constructed using the Cox model coefficients for the top features. The prognostic performance of CoRiS was evaluated on D2 (N=331), D3 (N=657) and D4 (N=242). Patients from D2 and D3 which comprised surgery + chemotherapy were used to validate CoRiS as predictive of added benefit to adjuvant chemotherapy (ACT) by comparing survival between different CoRiS defined risk groups. FINDINGS: CoRiS was found to be prognostic on univariable analysis, D2 (hazard ratio (HR) = 1.41, adjusted (adj.) P = .01) and D3 (HR = 1.35, adj. P < .001). Multivariable analysis showed CoRiS was independently prognostic, D2 (HR = 1.41, adj. P < .001) and D3 (HR = 1.35, adj. P < .001), after adjusting for clinico-pathologic factors. CoRiS was also able to identify high-risk patients who derived survival benefit from ACT D2 (HR = 0.42, adj. P = .006) and D3 (HR = 0.46, adj. P = .08). INTERPRETATION: CoRiS is a tissue non-destructive, quantitative and low-cost tool that could potentially help guide management of ES-NSCLC patients. FUNDING: Data collection, anlaysis, and computation resources of the research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health under award numbers: 1U24CA199374-01, R01CA202752-01A1, R01CA208236-01A1, R01 CA216579-01A1, R01 CA220581-01A1, 1U01 CA239055-01. National Center for Research Resources under award number 1 C06 RR12463-01. VA Merit Review Award IBX004121A from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service, the DOD Prostate Cancer Idea Development Award (W81XWH-15-1-0558), the DOD Lung Cancer Investigator-Initiated Translational Research Award (W81XWH-18-1-0440), the DOD Peer Reviewed Cancer Research Program (W81XWH-16-1-0329), the Ohio Third Frontier Technology Validation Fund, the Wallace H. Coulter Foundation Program in the Department of Biomedical Engineering and the Clinical and Translational Science Award Program (CTSA) at Case Western Reserve University.

Chemotherapy-induced CDA expression renders resistant non-small cell lung cancer cells sensitive to 5'-deoxy-5-fluorocytidine (5'-DFCR).

BACKGROUND: Pemetrexed (MTA) plus cisplatin combination therapy is considered the standard of care for patients with advanced non-small-cell lung cancer (NSCLC). However, in advanced NSCLC, the 5-year survival rate is below 10%, mainly due to resistance to therapy. We have previously shown that the fraction of mesenchymal-like, chemotherapy-resistant paraclone cells increased after MTA and cisplatin combination therapy in the NSCLC cell line A549. Cytidine deaminase (CDA) and thymidine phosphorylase (TYMP) are key enzymes of the pyrimidine salvage pathway. 5'-deoxy-5-fluorocytidine (5'-DFCR) is a cytidine analogue (metabolite of capecitabine), which is converted by CDA and subsequently by TYMP into 5-fluorouracil, a chemotherapeutic agent frequently used to treat solid tumors. The aim of this study was to identify and exploit chemotherapy-induced metabolic adaptations to target resistant cancer cells. METHODS: Cell viability and colony formation assays were used to quantify the efficacy of MTA and cisplatin treatment in combination with schedule-dependent addition of 5'-DFCR on growth and survival of A549 paraclone cells and NSCLC cell lines. CDA and TYMP protein expression were monitored by Western blot. Finally, flow cytometry was used to analyze the EMT phenotype, DNA damage response activation and cell cycle distribution over time after treatment. CDA expression was measured by immunohistochemistry in tumor tissues of patients before and after neoadjuvant chemotherapy. RESULTS: We performed a small-scale screen of mitochondrial metabolism inhibitors, which revealed that 5'-DFCR selectively targets chemotherapy-resistant A549 paraclone cells characterized by high CDA and TYMP expression. In the cell line A549, CDA and TYMP expression was further increased by chemotherapy in a time-dependent manner, which was also observed in the KRAS-addicted NSCLC cell lines H358 and H411. The addition of 5'-DFCR on the second day after MTA and cisplatin combination therapy was the most efficient treatment to eradicate chemotherapy-resistant NSCLC cells. Moreover, recovery from treatment-induced DNA damage was delayed and accompanied by senescence induction and acquisition of a hybrid-EMT phenotype. In a subset of patient tumors, CDA expression was also increased after treatment with neoadjuvant chemotherapy. CONCLUSIONS: Chemotherapy increases CDA and TYMP expression thereby rendering resistant lung cancer cells susceptible to subsequent 5'-DFCR treatment.

Analysis of risk factors in thoracic trauma patients with a comparison of a modern trauma centre: a mono-centre study.

OBJECTIVES: Thoracic trauma (TT) is the third most common cause of death after abdominal injury and head trauma in polytrauma patients. Its management is still a very challenging task. The purpose of this study was to analyse the risk factors affecting the outcome in a high-volume trauma centre and the efficacy of a specialised trauma team in level 1 trauma centres. PATIENTS AND METHODS: Between January 2003 and December 2012, data of all patients admitted to the accident and emergency (A&E) department were prospectively collected at the German Trauma Registry (GTR) and thereafter retrospectively analysed. Patients with chest trauma, an Injury Severity Score (ISS) ≥ 18 and an Abbreviated Injury Scale (AIS) > 2 in more than one body region were included. Patients were divided into two groups: group I included patients presenting with thoracic trauma between January 2003 and December 2007. The results of this group were compared with the results of another group (group II) in a later 5-year period (Jan. 2008-Dec. 2012). Univariate and multivariate analyses were performed, and differences with p < 0.05 were considered statistically significant. RESULTS: There were 630 patients (56%) with thoracic trauma. A total of 540 patients (48%) had associated extrathoracic injuries. Group I consisted of 285 patients (197 male, mean age 46 years). Group II consisted of 345 patients (251 male, mean age 49 years). Overall 90-day mortality was 17% (n = 48) in group I vs. 9% (n = 31) in group II (p = 0.024). Complication rates were higher in group I (p = 0.019). Higher Injury Severity Scores (ISSs) and higher Abbreviated Injury Acale (AIS) scores in the thoracic region yielded a higher rate of mortality (p < 0.0001). Young patients (< 40 years) were frequently exposed to severe thoracic injury but showed lower mortality rates (p = 0.014). Patients with severe lung contusions (n = 94) (15%) had higher morbidity and mortality (p < 0.001). Twenty-three (8%) patients underwent emergency thoracotomy in group I vs. 14 patients (4%) in group II (p = 0.041). Organ replacement procedures were needed in 18% of patients in group I vs. 31% of patients in group II (p = 0.038). CONCLUSIONS: The presence of severe lung contusion, a higher ISS and AISthoracic score and advanced age are independent risk factors that are directly related to a higher mortality rate. Management of blunt chest trauma with corrective chest tube insertion, optimal pain control and chest physiotherapy results in good outcomes in the majority of patients. Optimal management with better survival rates is achievable in specialised centres with multidisciplinary teamwork and the presence of thoracic surgical experience.

Tumor Initiation Capacity and Therapy Resistance Are Differential Features of EMT-Related Subpopulations in the NSCLC Cell Line A549.

Cell lines are essential tools to standardize and compare experimental findings in basic and translational cancer research. The current dogma states that cancer stem cells feature an increased tumor initiation capacity and are also chemoresistant. Here, we identified and comprehensively characterized three morphologically distinct cellular subtypes in the non-small cell lung cancer cell line A549 and challenge the current cancer stem cell dogma. Subtype-specific cellular morphology is maintained during short-term culturing, resulting in the formation of holoclonal, meroclonal, and paraclonal colonies. A549 holoclone cells were characterized by an epithelial and stem-like phenotype, paraclone cells featured a mesenchymal phenotype, whereas meroclone cells were phenotypically intermediate. Cell-surface marker expression of subpopulations changed over time, indicating an active epithelial-to-mesenchymal transition (EMT), in vitro and in vivo. EMT has been associated with the overexpression of the immunomodulators PD-L1 and PD-L2, which were 37- and 235-fold overexpressed in para- versus holoclone cells, respectively. We found that DNA methylation is involved in epigenetic regulation of marker expression. Holoclone cells were extremely sensitive to cisplatin and radiotherapy in vitro, whereas paraclone cells were highly resistant. However, inhibition of the receptor tyrosine kinase AXL, whose expression is associated with an EMT, specifically targeted the otherwise highly resistant paraclone cells. Xenograft tumor formation capacity was 24- and 269-fold higher in holo- than mero- and paraclone cells, respectively. Our results show that A549 subpopulations might serve as a unique system to explore the network of stemness, cellular plasticity, tumor initiation capacity, invasive and metastatic potential, and chemo/radiotherapy resistance.

Langerhans cell histiocytosis as differential diagnosis of a mediastinal tumor.

We describe the case of a 55-year-old man who presented with parasternal swelling. The chest CT scan showed a large tumor of the chest wall infiltrating the subcutaneous tissue. To assume histologic diagnosis an open biopsy was performed. Between the myofibrils a coarse, white tumor with infiltrative growth was noted. Histopathologic examination revealed expanded atrophic skeletal muscle that was infiltrated by histiocytic cells. Numerous eosinophilic granulocytes and lymphocytes CD20 and CD3 positive could be detected and immunohistochemical staining was also positive for S-100 proteins and CD1a. Histologic findings were characteristic of Langerhans cell histiocytosis (LCH). To the best of our knowledge a LCH originating from the mediastinum in an adult as presented has not been previously described.

Comparison of procalcitonin and CrP in the postoperative course after lung decortication.

OBJECTIVE: The objective of this prospective study was to compare the clinical value of procalcitonin (PCT) and C-reactive protein (CrP) plasma concentrations in their postoperative course after decortication. METHODS: Twenty-two patients requiring surgery for pleural empyema were chosen for this prospective study. Routine blood samples including CrP and PCT plasma concentrations were taken before the operation and on the 1st, 2nd, 3rd, and 7th postoperative day. RESULTS: Due to infection PCT and CrP were elevated preoperatively. In the postoperative course both PCT and CrP reached peak-levels on day 2 with values up to 43.55 ng/ml and 384.00 mg/l, respectively. In PCT the rise was followed by a clear decrease in 20 (90.9 %) patients until day 7. In contrast the CrP levels decreased slowly and only seven (54.5%) patients had values of 100 mg/l or below on day 7. PCT showed a better correlation with the clinic in case of septic course than CrP does. CONCLUSIONS: PCT reflects postoperative clinical course more accurately than CrP. Therefore, PCT is a more appropriate laboratory parameter to monitor patients after surgery for pleural empyema.

Effect of pregnancy and birth on the course of myasthenia gravis before or after transsternal radical thymectomy.

OBJECTIVE: Myasthenia gravis (MG) affects women at childbearing age. Therefore, the question arises if these patients should become pregnant and if thymectomy has a positive effect on the course of MG in pregnant patients. METHODS: Fifteen pregnancies had been followed retrospectively. All patients underwent transsternal radical thymectomy for MG. The course of MG in the period before, during, and after the pregnancy was scored according to Ossermann's classification. The effect of thymectomy on delivery and on the newborns was evaluated. RESULTS: Patients were divided in two groups: pregnancies before (group I, n=8) and after (group II, n=7) thymectomy. During pregnancy, in group I, one deterioration was observed and in seven patients the disease was unchanged. In group II, one deterioration, five unchanged courses, and one improvement were observed. In the postpartum period, in group I, seven patients did not change and one improved. In group II, two deteriorations, three unchanged courses, and two improvements were observed. Before pregnancy, group II patients were in a better Ossermann stage in comparison with those in group I. Eight of the 12 deliveries were spontaneous (three abortus). Myasthenic symptoms were observed in two newborns in group I. CONCLUSION: Our data suggest that MG is not prohibitive to have children. The course of MG after transsternal radical thymectomy is often ameliorated. A better MG-stage, reached after thymectomy, before pregnancy seems to be correlated with a better course during pregnancy.

Nuss procedure for pectus excavatum in adults: long-term results in a prospective observational study.

OBJECTIVES: Since the end of the 1990s, the management of pectus excavatum has undergone major changes. The Nuss procedure (pectus bar) has been the method of choice for patients with pectus excavatum at Bern University Hospital for over a decade. The current study will describe our experiences, with a particular focus on long-term results in adults. METHODS: The prospective observational study began in autumn 2002. The Haller index was used to quantify pectus excavatum severity. Pulmonary function tests and cardiac examinations were performed preoperatively, and a standardized management for surgical techniques and for the pre- and postoperative treatments including long-term follow-up at 3, 12 and 36 months after surgery was developed. Quality of life and satisfaction with the cosmetic result after the Nuss procedure were evaluated. RESULTS: Better or much better quality of life after the Nuss procedure was observed: n = 108 (88.4%) at 3 months, n = 97 (89.0%) at 12 months and n = 87 (92.5%) at 36 months. Pain intensity decreased in the follow-up [pain score visual analogue scale (VAS) at 3 months: median 1 (0-7), 12 months: median 1 (0-4), 36 months: median 0.8 (0-5)]. After long-term observation, over 90% of patients described their quality of life after the operation as being better or much better. Satisfaction with the cosmetic results of the operation was also very high, with >90% of patients being satisfied. Only a very small group of patients suffered from pain in the long-term follow-up. Complications were rare (14.7%) and could be treated in most cases without reoperation. CONCLUSION: Our results demonstrate that the Nuss procedure is safe and can be performed with excellent results in adults, both in the short term and in the long term. The improved quality of life and patients' satisfaction with cosmetic results remained high in the long-term follow-up, 10 years after the surgical procedure.

Strong additive effect of 1,25-dihydroxycholecalciferol and cyclosporine A but not tacrolimus in rat lung allotransplantation.

OBJECTIVES: 1,25-Dihydroxycholecalciferol (calcitriol, vitamin D3) has immunosuppressive properties. This study evaluates the effect of calcitriol in combination with either cyclosporine A or tacrolimus on acute lung allograft rejection in a rat model of unilateral left lung allotransplantation. METHODS: Unilateral left lung transplantation was performed in male rats (Brown-Norway to Fischer F344, 200-250 g body weight). For immunosuppression, the following subtherapeutic doses were used: calcitriol 0.5 microg/kg/day, cyclosporine A 2.5 mg/kg/day i.p., and tacrolimus 40 microg/kg i.m. Five groups (n = 5) were analyzed: cyclosporine A; cyclosporine A and calcitriol; calcitriol; tacrolimus and calcitriol; and tacrolimus. The injections were performed for 5 days starting from the day of transplantation. Recipients were sacrificed on day 5 post-transplant. The contralateral right main bronchus and pulmonary artery were occluded for 5 min and blood was drawn for blood gas analysis. The grafts were excised, fixed in formaline and embedded in paraffin. Histological evaluation was done in blinded fashion (ISHLT 1999/rank scale). The mean and standard error of the mean (PaO2) or the median and range (rejection grading) are given. ANOVA followed by planned comparison for the PaO2 and Kruskal-Wallis ANOVA for rejection grading were applied, p < 0.05 considered significant. RESULTS: Arterial PaO2 on day 5 was very low in animals treated with subtherapeutic dosages of either cyclosporine A (48 +/- 10 mmHg), calcitriol (51 +/- 3) or tacrolimus (86 +/- 22). Combined treatment with cyclosporine A and calcitriol revealed a significant improvement (248 +/- 78; p < 0.05 vs. other groups), whereas the combination of tacrolimus with calcitriol did not reveal any benefit (65 +/- 9). Rejection grading with these subtherapeutic doses did not show any significant difference between groups. CONCLUSIONS: Our data indicate that cyclosporine A, but not tacrolimus, has a strong additive effect with calcitriol on acute rat lung allograft rejection.

High expression of octamer-binding transcription factor 4A, prominin-1 and aldehyde dehydrogenase strongly indicates involvement in the initiation of lung adenocarcinoma resulting in shorter disease-free intervals.

OBJECTIVES: The increasing relevance of the cancer stem cell (CSC) hypothesis and the impact of CSC-associated markers in the carcinogenesis of solid tumours may provide potential prognostic implications in lung cancer. We propose that a collective genetic analysis of established CSC-related markers will generate data to better define the role of putative CSCs in lung adenocarcinoma (LAC). METHODS: Sixty-four paired tumour and non-tumour biopsies from LAC patients were included in this study. Using the quantitative reverse transcriptase-polymerase chain reaction, we assessed the expression profiles of established CSC-related biomarkers: octamer-binding transcription factor 4 (OCT4A), CD133, aldehyde dehydrogenase (ALDH), BMI-1, ATP-binding cassette subfamily G, member 2 (ABCG2), SRY (sex-determining region Y)-box 2 (SOX2) and uPAR, and evaluated their relation to clinicopathological parameters and disease prognosis. RESULTS: All of the above-mentioned CSC-related markers were detectable in both tumour and corresponding normal tissues. Importantly, expression levels of OCT4A, CD133, BMI-1, SOX2 and uPAR were significantly higher (OCT4A, P = 0.0003; CD133, P = 0.002; BMI-1, P = 0.04; SOX2, P = 0.0003; uPAR, P = 0.03) in the tumour compared with those in the non-tumour tissues. By contrast, the quantities of ACBG2 and ALDH were markedly reduced (ACBG2, P = 0.0006; ALDH, P = 0.007) in the tumour relative to those in the normal biopsies. Using multivariate analysis, elevated ALDH and CD133 revealed significant associations in tumour stage (ALDH, P = 0.03; CD133, P = 0.007) and differentiation (ALDH, P = 0.03; CD133, P = 0.018). We observed that ALDH and OCT4A were associated with nodal status (ALDH, P = 0.05; OCT4A, P = 0.03) having lower mRNA levels in tumours with lymph node metastasis, N+, compared with that in N0. High OCT4A levels were significantly correlated with tumour size of <3 cm, decrease in tumours >3 cm (P = 0.03). Kaplan-Meier correlation analyses, showed that OCT4A and CD133 were correlated to short disease-free intervals (OCT4A, P = 0.047; CD133, P = 0.033) over a period of 29 months. CONCLUSIONS: Our study reveals that CSC-associated markers: OCT4A, CD133 and ALDH are involved in the initial phase of carcinogenesis of LAC, and can be used as predictors of early stage LAC and poor disease-free intervals. In addition, this work validates the relevance of the CSC hypothesis in LAC.

1,25-Dihydroxycholecalciferol with low-calcium diet reduces acute rejection in rat lung allotransplantation.

OBJECTIVES: The effect of 1,25-dihydroxycholecalciferol (calcitriol, vitamin D3) with a low-calcium diet on the acute lung allograft rejection in a rat unilateral left lung transplantation model was evaluated. METHODS: Three transplantation groups were studied (n = 5, male Brown-Norway to Fischer F344, 235 ± 15 g body weight): calcitriol and low-calcium diet, low-calcium diet and normal diet. Calcitriol (4 µg/kg/day) was injected intraperitoneally for 5 days, starting from the day of transplantation. In addition, two non-transplantation groups were compared: (n = 3, Brown-Norway) to measure the level of cytokines, and Fischer F344 receiving calcitriol and a low-calcium diet to measure the serum calcium level. The recipients of transplantation were killed on Day 5 post-transplant. The contralateral right main bronchus and the pulmonary artery were occluded for 5 min and blood was drawn for the blood gas analysis, and the grafts were assessed for histology (International Society for Heart and Lung Transplantation 1996/rank scale). Lung levels of interleukin (IL)-2, IL-6, IL-12 and tumour necrosis factor-α (TNF-α) were assessed within the calcitriol and low-calcium diet, low-calcium diet and Brown-Norway groups. The serum calcium level was assessed in the Fischer F344 group. An analysis of variance with Tukey's post hoc test was used to compare the arterial blood oxygen pressure and the lung cytokine expression between groups. A non-parametric Kruskal-Wallis test followed by the Siegel and Castellan post hoc test was used to assess the differences between the groups according to the lung graft rejection grading. Student's paired t-test was used to compare the serum calcium level. RESULTS: The arterial PaO(2) was significantly higher in the calcitriol and the low-calcium diet groups when compared with low-calcium diet or normal diet groups (356 ± 72 mmHg; P < 0.05 vs other groups). The arterial and bronchial rejection observed in calcitriol and low-calcium diet group was significantly milder than in the low-calcium diet or normal diet groups (A1-2, B1-2; P < 0.05 vs other groups). IL-2 and IL-6 levels were significantly higher in low-calcium diet vs calcitriol and low-calcium diet and Brown-Norway groups. IL-12 and TNF-α did not differ among the groups. There was no significant difference in serum calcium level before and after the treatment in the Fischer F344 group. CONCLUSIONS: Calcitriol with a low-calcium diet treatment improves lung function, reduces lung allograft acute rejection, decreases IL-2 and IL-6 allograft expression and does not change the serum calcium level significantly.

Four-arm robotic lobectomy for the treatment of early-stage lung cancer.

OBJECTIVES: We investigated the feasibility and safety of four-arm robotic lung lobectomy in patients with lung cancer and described the robotic lobectomy technique with mediastinal lymph node dissection. METHODS: Over 21 months, 54 patients underwent robotic lobectomy for early-stage lung cancer at our institute. We used a da Vinci Robotic System (Intuitive Surgical, Inc, Mountain View, Calif) with three ports plus one utility incision to isolate hilum elements and perform vascular and bronchial resection using standard endoscopic staplers. Standard mediastinal lymph node dissection was performed subsequently. Surgical outcomes were compared with those in 54 patients who underwent open surgery over the same period and were matched to the robotic group using propensity scores for a series of preoperative variables. RESULTS: Conversion to open surgery was necessary in 7 (13%) cases. Postoperative complications (11/54, 20%, in each group) and median number of lymph nodes removed (17.5 robotic vs 17 open) were similar in the 2 groups. Median robotic operating time decreased by 43 minutes (P = .02) from first tertile (18 patients) to the second-plus-third tertile (36 patients). Median postoperative hospitalization was significantly shorter after robotic (excluding first tertile) than after open operations (4.5 days vs 6 days; P = .002). CONCLUSIONS: Robotic lobectomy with lymph node dissection is practicable, safe, and associated with shorter postoperative hospitalization than open surgery. From the number of lymph nodes removed it also appears oncologically acceptable for early lung cancer. Benefits in terms of postoperative pain, respiratory function, and quality of life still require evaluation. We expect that technologic developments will further simplify the robotic procedure.