Tomoshi Tsuchiya

Life span extension by reduction of the growth hormone-insulin-like growth factor-1 axis: relation to caloric restriction.

A reduced growth hormone (GH)‐insulin‐like growth factor (IGF)‐1 axis is associated with an extension of lifespan in laboratory rodents. Several phenotypes of such animal models resemble those induced by caloric restriction (CR). Using a transgenic male Wistar rat model whose GH‐IGF‐1 axis was moderately suppressed by overexpression of the antisense GH transgene (tg), we elucidated a relationship between the effects of a reduced GH‐IGF‐1 axis and CR for some biomarkers of aging, lifespan, and pathologies. Heterozygous (tg/−) rats fed ad libitum (AL) had a dwarf phenotype similar to that of control nontransgenic (−/−) rats subjected to 30% CR from 6 wk of age. Both the reduced GH‐IGF‐1 axis and CR extended lifespan to a similar extent, although the effect of CR seemed to be greater. There was an additive effect of CR to lifespan extension when tg/− rats were subjected to CR. Pathologic analyses indicated that the preventive effect of CR on selected diseases was greater than that of the reduced GH‐IGF‐1 axis. The present study suggests that CR affects aging and longevity by mechanisms other than suppression of the GH‐IGF‐1 axis, although CR might exhibit its effects partly through the reduced GH‐IGF‐1 axis.

KrasG12D and Nkx2-1 haploinsufficiency induce mucinous adenocarcinoma of the lung

Mucinous adenocarcinoma of the lung is a subtype of highly invasive pulmonary tumors and is associated with decreased or absent expression of the transcription factor NK2 homeobox 1 (NKX2-1; also known as TTF-1). Here, we show that haploinsufficiency of Nkx2-1 in combination with oncogenic Kras(G12D), but not with oncogenic EGFR(L858R), caused pulmonary tumors in transgenic mice that were phenotypically similar to human mucinous adenocarcinomas. Gene expression patterns distinguished tumor goblet (mucous) cells from nontumorigenic airway and intestinal goblet cells. Expression of NKX2-1 inhibited urethane and oncogenic Kras(G12D)-induced tumorigenesis in vivo. Haploinsufficiency of Nkx2-1 enhanced Kras(G12D)-mediated tumor progression, but reduced EGFR(L858R)-mediated progression. Genome-wide analysis of gene expression demonstrated that a set of genes induced in mucinous tumors was shared with genes induced in a nontumorigenic chronic lung disease, while a distinct subset of genes was specific to mucinous tumors. ChIP with massively parallel DNA sequencing identified a direct association of NKX2-1 with the genes induced in mucinous tumors. NKX2-1 associated with the AP-1 binding element as well as the canonical NKX2-1 binding element. NKX2-1 inhibited both AP-1 activity and tumor colony formation in vitro. These data demonstrate that NKX2-1 functions in a context-dependent manner in lung tumorigenesis and inhibits Kras(G12D)-driven mucinous pulmonary adenocarcinoma.

Clinical and molecular analysis of synchronous double lung cancers

BACKGROUND Since multiple lung cancer treatment strategies differ, it is essential for clinicians to be able to distinguish between separate primary lesions and metastasis. In the present study, we used array comparative genomic hybridization (aCGH) and somatic mutation (epidermal growth factor receptor: EGFR) to analyze genomic alteration profiles in lung cancer patients. To validate the consistency among the pathological assessments and clarify the clinical differences between double primary lesions and metastasis, we also examined synchronous double lung cancer clinical data. METHODS Between January 1970 and March 2010, 2215 patients with lung cancer underwent surgical resection at Nagasaki University Hospital. We performed molecular analysis of 12 synchronous double lung cancer patients without lymph node metastasis (intrapulmonary metastasis in the same lobe (pm1): n=6, primary: n=6). We then evaluated the clinical outcomes of patients with pathologically diagnosed synchronous double lung cancers (intrapulmonary metastasis (pm): n=80, primary: n=39) and other T3 tumors (n=230). RESULTS Examination of the concordance rate (CR) of the copy number changes (CNCs) for paired tumors showed that the metastasis group was larger than the primary group (55.5% vs. 19.6%, p=0.04). Pathological diagnosis and molecular classification were the same in 10 out of 12 cases (83%). As compared to the primary group, there tended to be an inferior 5-year survival curve for the pm group. However, in N0 patients, the survival curve for the pm group overlapped the primary group, while the survival rate of the pm1 group was much higher than that of other T3 group (p<0.01). CONCLUSIONS Both pathological and molecular assessment using aCGH adapted in the current study appeared to have a consistency. Pathological pm1(T3)N0 patients may have a better prognosis than other T3N0 patients.

Assessment and follow-up of intercostal nerve damage after video-assisted thoracic surgery.

OBJECTIVE Chronic pain is a common complication after thoracic surgery. The most important factor appears to be intercostal nerve damage. The purpose of this prospective study was to objectively evaluate intercostal nerve damage associated with post-thoracotomy pain after three surgical procedures using current perception threshold testing. METHODS The 32 patients were classified into three groups: the video-assisted thoracic surgery group (n=7), the video-assisted minithoracotomy with metal retractors group (n=15), and the conventional thoracotomy group (n=10). Intercostal nerve function was assessed by a series of 2000-Hz (Aβ fiber), 250-Hz (Aδ fiber), and 5-Hz (C fiber) stimuli using current perception threshold testing (Neurometer CPT/C). The current perception threshold values were measured before and 1, 2, 4, 12, and 24 weeks after surgery. The intensities of ongoing pain were also assessed using a numeric rating scale (0-10). RESULTS The video-assisted thoracic surgery group showed no changes in any current perception threshold values and no residual pain more than 12 weeks after surgery. The video-assisted minithoracotomy with metal retractors group and the conventional thoracotomy group showed significantly higher current perception threshold values at 2000 Hz 1 week after surgery (p=0.0013, p=0.0012, respectively), with pain in approximately 70% of patients 12 weeks after surgery. The correlation between current perception threshold values at 2000 Hz and the intensities of ongoing pain 4 and 12 weeks after surgery was significant (p=0.03, p=0.04, respectively). CONCLUSIONS This is the first study that objectively evaluated pain after video-assisted thoracic surgery. The results suggest that the Aβ and Aδ fibers play a significant role in the development of intercostal nerve damage. The current perception threshold values clearly demonstrated that video-assisted thoracic surgery is a less-invasive procedure resulting in less post-thoracotomy pain and, they have some possibilities to objectively evaluate the ongoing pain after surgery.

Future prospects for tissue engineered lung transplantation: decellularization and recellularization-based whole lung regeneration.

The shortage of donor lungs for transplantation causes a significant number of patient deaths. The availability of laboratory engineered, functional organs would be a major advance in meeting the demand for organs for transplantation. The accumulation of information on biological scaffolds and an increased understanding of stem/progenitor cell behavior has led to the idea of generating transplantable organs by decellularizing an organ and recellularizing using appropriate cells. Recellularized solid organs can perform organ-specific functions for short periods of time, which indicates the potential for the clinical use of engineered solid organs in the future. The present review provides an overview of progress and recent knowledge about decellularization and recellularization-based approaches for generating tissue engineered lungs. Methods to improve decellularization, maturation of recellularized lung, candidate species for transplantation and future prospects of lung bioengineering are also discussed.

Dietary restriction reduces hepatocyte proliferation and enhances p53 expression but does not increase apoptosis in normal rats during development.

Abstract. Dietary restriction (DR) retards physical growth, resulting in small body size, reduced liver weight and reduced number of hepatocytes in rats. We examined the effects of DR on proliferation and apoptosis of hepatocytes during development and explained these changes subcellularly using immunohistochemistry for bromodeoxyuridine (BrdU) incorporation, proliferating cell nuclear antigen (PCNA) and p53, terminal dUTP nick end labeling (TUNEL) and quantitative reverse transcription-polymerase chain reaction (RT-PCR) for TGFα, TGFβ1, p53, Fas and TNF receptor (TNFr). Tissue samples included the livers of 3-month-old male Fischer 344 rats fed ad libitum (AL) or on 70% DR. DR significantly reduced the proportions of BrdU-positive and PCNA-strongly-positive hepatocytes compared with AL rats but not the proportions of PCNA-positive hepatocytes and TUNEL-positive hepatocytes. On the other hand, DR enhanced the expression of p53 and Fas mRNAs but failed to influence the expression of TGFα, TGFβ1 and TNFr mRNAs. Moreover, DR significantly increased the proportion of p53-positive hepatocytes. Our findings suggest that DR suppresses the proliferation of hepatocytes, resulting in a reduced number of hepatocytes during development. This process may be mediated by overexpression of p53 suppressor gene. While DR accelerates the expression of Fas antigen, this result does not influence the rate of apoptosis of hepatocytes under physiological conditions.

Inflammation-based scoring is a useful prognostic predictor of pulmonary resection for elderly patients with clinical stage I non-small-cell lung cancer

OBJECTIVES The number of elderly lung cancer patients requiring surgery has been increasing due to the ageing society and less invasive perioperative procedures. Elderly people usually have various comorbidities, but there are few simple and objective tools that can be used to determine prognostic factors for elderly patients with clinical stage I non-small-cell lung cancer (NSCLC). The aim of this retrospective study was to evaluate the prognostic factors of surgically treated, over 80-year old patients with clinical stage I NSCLC. METHODS The preoperative data of 97 over 80-year old patients with clinical stage I NSCLC were collected at Nagasaki University Hospital from 1990 to 2012. As prognostic factors, inflammation-based scoring systems, including the Glasgow Prognostic Score (GPS) determined by serum levels of C-reactive protein and albumin, the neutrophil lymphocyte ratio (NLR) and the platelet lymphocyte ratio (PLR) were evaluated, as well as other clinicopathological factors, including performance status, body mass index, carcinoembryonic antigen, Charlson comorbidity index and type of surgical procedure. RESULTS The median age was 82 (range, 80-93) years. There were 62 (64.0%) clinical stage IA cases and 35 IB cases. Operations included 64 (66.0%) lobectomies, 15 segmentectomies and 18 wedge resections. The pathological stage was I in 76 (78.4%) patients, II in 12 (12.4%), III in 8 (8.2%) and IV in 1 (1.0%). Twelve (12.4%) patients underwent mediastinal lymph node dissection. Overall survival and disease-specific 5-year survival rates were 55.5 and 70.0%, respectively. The average GPS score was 0.4 (0-2). Disease-specific 5-year survival was significantly longer with GPS 0 than with GPS 1-2. (74.2%, 53.7%, respectively, P = 0.03). Overall 5-year survival was significantly longer with GPS 0 than with GPS 1-2. (59.7%, 43.1%, respectively, P = 0.005). Both the NLR (median value = 1.9) and the PLR (median value = 117) were not correlated with disease-specific and overall 5-year survival. On multivariate analysis, pathological stage I (P = 0.01) and GPS 0 (P = 0.04, hazard ratio: 2.13, 95% confidence interval 1.036-4.393) were significant prognostic factors. CONCLUSIONS The preoperative GPS appears to be a useful predictor of overall survival and could be a simple prognostic tool for elderly patients with clinical stage I NSCLC.

Primary low-grade MALT lymphoma of the gallbladder

We report a case of primary low‐grade B‐cell lymphoma of the mucosa‐associated lymphoid tissue (low‐grade MALT lymphoma) in the gallbladder. A 58‐year‐old woman suspected of gallbladder carcinoma underwent laparoscopic cholecystectomy. Microscopic examination of the gallbladder demonstrated lymphoid cell infiltration forming lymphoid follicles with hyperplastic secondary follicles. The surrounding monocytoid B cells and centrocyte‐like cells selectively infiltrated the crypt epithelium forming lympho‐epithelial lesions. Plasma cells were also noted beneath the mucosal epithelium. Bile culture revealed the Gram‐negative bacilli Enterococcus faecalis and Morganella morganii. Immunoglobulin heavy chain gene rearrangement was confirmed using polymerase chain reaction (PCR) and oligoclonal lymphoid proliferations was detected. Because autoimmune diseases, or chronic inflammatory disorders, seem to correlate with the occurrence of MALT lymphoma, Gram‐negative bacterial infection could also be considered as a prodrome of MALT lymphoma of the gallbladder.

Intravenous injection of cycloheximide induces apoptosis and up-regulates p53 and Fas receptor expression in the rat liver in vivo.

A single administration of protein synthesis inhibitor, cycloheximide (CHX) induces apoptosis of hepatocytes in vivo. We investigated the underlying mechanisms of this phenomenon and the role of p53 and Fas receptor using terminal dUTP nick end labeling (TUNEL), quantitative reverse transcription polymerase chain reaction and immunohistochemistry. Rat liver tissue specimens were obtained at different time intervals after injection of CHX. The proportion of TUNEL-positive apoptotic hepatocytes increased with time and reached a plateau at 2.5h after the injection. The p53 and Fas receptor mRNAs and the proportion of immunoreactive p53-positive and Fas receptor-positive hepatocytes increased markedly with time from 1h after the administration. Since the time course of increased proportion of apoptotic hepatocytes does not parallel that of p53- or Fas receptor-positive hepatocytes and apoptotic hepatocytes appeared prior to up-regulation of p53 and Fas receptor expression, it is likely that the enhanced expression of p53 and Fas receptor is not involved directly in CHX-induced apoptosis of hepatocytes in vivo. Rats injected with a single intravenous dose of CHX, however, provide a simple and useful model for investigating the apoptotic machinery and the molecular mechanism of transcriptional up-regulation of p53 and Fas receptor in hepatocytes.

Airway stent insertion simulated with a three-dimensional printed airway model.

A 30-year-old man underwent right single-lung transplantation for chronic obstructive pulmonary disease. The bronchial anastomosis developed ischemic change, resulting in stenosis of the intermediate bronchus. A modified Y-shaped airway stent with the fabricated orifice of the upper lobe was inserted by rigid bronchoscopy. Before the operation, a three-dimensional printed bronchial model of this patient was made for surgical simulation. This model enabled us to perform the operation easily, quickly, and successfully. The patients condition improved after airway stent insertion. The three-dimensional printed airway model provided sufficient preoperative understanding of the patients anatomy for planning the surgical procedure.