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In COVID-19 pneumonia, early detection and appropriate treatment are essential to prevent severe exacerbation. Therefore, it is important to understand the initiating events of COVID-19 pneumonia. However, at present, the literature about early stage disease has been very limited. Here, we investigated the earliest histopathological changes and gene expression profiles associated with COVID-19 pneumonia.We carefully examined 25 autopsied cases with different clinical courses. Dilation of capillaries and edematous thickening of the alveolar septa were found even in areas that macroscopically looked almost normal. Pneumocytes, histocytes/macrophages, and vascular endothelial cells were immunohistochemically positive for tissue factor, which is an important early responder to tissue injuries. Comprehensive gene expression analyses revealed that those lesions presented differential profiles compared to those of control lungs and were associated with a significant upregulation of the lysosomal pathway.Alveolar capillary dilation and edematous thickening may be the earliest histopathological change detected in COVID-19 pneumonia. Intensive investigations of such lesions may lead to an understanding of the initiating event of not only COVID-19 pneumonia but also of general diffuse alveolar damage.

Nevi are benign melanocytic tumors, and some nevi are considered to develop into malignant melanomas. Most nevi arise in the skin, but nevi occasionally occur in the conjunctiva, esophageal mucosa, or at other sites. Pulmonary melanocytic nevi are extremely rare, and only one case has been reported in the literature. Here, we present a case of pulmonary melanocytic nevus, involving a BRAF gene mutation (V600E), and we discuss the potential significance of this condition as a precursor to pulmonary malignant melanoma.

The present study aimed to elucidate the mechanisms underlying the histogenesis of interstitial pneumonia (IP)-related lung adenocarcinoma (LADC). We focused on the methylation of thyroid transcription factor 1 (TTF-1). The TTF-1 locus was highly methylated in IP-LADCs compared to non-IP-LADCs. Among the IP-LADCs, the non-terminal respiratory unit (TRU) LADCs showed marked hypermethylation in CpG sites in a particular intragenic region. This region was also found to be highly methylated in the IP lungs. The hierarchical dendrogram based on methylation levels divided the IP lungs into three different clusters. One of them showed a methylation profile similar to that of non-TRU LADCs. The non-TRU LADCs developed from this cluster with a significantly higher frequency. Moreover, bronchiolar metaplasia lining honeycomb/cystic lesions in IP lungs, IP-related non-TRU LADCs, and bronchiolar epithelia in healthy lungs were separately collected by microdissection and examined for methylation. Bronchiolar metaplasia showed hypermethylation, but bronchiolar epithelia did not. The methylation patterns in bronchiolar metaplasia were similar to those in non-TRU LADCs. In summary, a particular region of TTF-1 was highly methylated in IP-related non-TRU LADCs and bronchiolar metaplasia, supporting the theory that IP-related non-TRU LADCs may develop from bronchiolar metaplasia lining honeycomb/cystic lesions.

The present study aimed to discern the molecular alterations involved in the progression of EGFR-mutated lung adenocarcinoma (LADC). We previously demonstrated that the micropapillary (mPAP) element is the most important histological factor for assessing malignant grades in LADCs. Therefore, mPAP and other elements were separately collected from three cases of EGFR-mutated LADC using laser capture microdissection and subjected to a comprehensive mRNA expression analysis. We focused on DYRK2 in this study because its level showed a substantial increase in EGFR-mutated LADCs with mPAP. We also immunohistochemically examined 130 tumors for the expression of DYRK2. The results confirmed a strong expression of DYRK2 in EGFR-mutated LADC with mPAP. Fluorescent in situ hybridization (FISH) analyses targeting the DYRK2 locus revealed frequent gene amplification in EGFR-mutated LADC, specifically occurring in the high-grade components, like mPAP. In summary, the results of this study suggest that DYRK2 overexpression through gene amplification is one of the molecular mechanisms responsible for promoting the progression of EGFR-mutated LADC.

A 93-year-old woman was admitted with a 10-day history of cough and prostration. Thoracic computed tomography revealed extensive ground-glass opacities in both the lungs. The polymerase chain reaction test of sputum for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) was positive. She was treated with antiviral agents and steroid pulse therapy. However, her oxygen saturation gradually declined, and she died 10 days after hospitalization. The most important autopsy finding was fuzzily segmented diffuse alveolar damage (DAD) that expanded from the subpleural to the medial area. No remarkable changes were observed in organs other than the lungs. Therefore, pneumocytes were suggested as the primary target for SARS-CoV-2, which might explain why coronavirus infectious disease-19 is a serious condition. Thus, early treatment is essential to prevent viral replication from reaching a level that triggers DAD.

AIMS Proliferative activity, evaluated from the Ki-67 index, is a strong prognostic factor in lung adenocarcinoma (LADC). Here, we optimised a procedure to measure the Ki-67 index and establish the best cut-off value. METHODS AND RESULTS We examined 342 stage I LADCs for the immunohistochemical expression of Ki-67 using different antibodies, MIB1 and SP6. The results revealed the superior specificity of SP6; therefore, SP6 was used in subsequent analyses. Slides were scanned with a virtual slide system. Using software, tumour cells were counted in a whole tumour. Thereafter, the tumour was evenly subdivided into 0.25-mm2 tiles. The frequency of positive cells was counted in each tile of an invasive area or the whole tumour. We calculated the number of tumour cells required to produce a 95% confidence interval (CI) 70% and CI of

Ciliated muconodular papillary tumors (CMPTs) are a recently categorized benign or low-grade malignant neoplasm that develops in the peripheral lung. Only about 40 cases have been reported to date, and the clinicopathological characteristics have yet to be defined in detail. Here, we present four cases of CMPTs with a focus on their immunohistochemical profiles and driver gene mutations. These tumors were a papillary proliferation of a mixture of ciliated, mucous, and basal cells located in the peripheral lung. Ciliated, mucous and basal cells were positive for TTF-1 when using the clone SPT24, but negative for HNF-4α. Basal cells were positive for p40. Mucous cells in some tumors were positive for MUC5AC and MUC6. The Ki-67 index was less than 5%, and strong expression of p53 was not detected. Three of the four tumors had a BRAF (V600E) driver mutation, an EGFR (del E746-T751/S752V) driver mutation, or driver mutations in both EGFR (E709G) and KRAS (G12V). These mutation types are rare for any histological type of lung cancer. The present results confirmed that CMPT is a neoplasm with immunohistochemical features and driver gene mutations that are distinct from those of common lung tumors.

We herein analyzed the relationships among the immunohistochemical expression of alpha-enolase (ENO1) and clinicopathological factors in order to define the significance of ENO1 in lung adenocarcinomas (ADCs). ENO1 expression was detected in most of the ADCs examined (95.8%), but not in bronchial and alveolar epithelia. ENO1 expression was typically observed in the cytoplasm among most ADCs (95.8%), but was also detected in the nucleus (56.3%). The levels were significantly higher in terminal respiratory unit (TRU) cytological subtype ADCs. Neither cytoplasmic nor nuclear expression was associated with any other clinicopathological factors including post-operative survival and growth activity. These results suggest that ENO1 is a crucial factor promoting neoplastic transformation exclusively in TRU subtype ADCs. We also investigated the potential utility of the immunohistochemical expression of ENO1 to differentiate TRU-type ADC cells from the reactive hyperplasia of pneumocytes and bronchiolar epithelial cells because difficulties are associated with discriminating these lesions in small biopsy specimens. The sensitivity and specificity of ENO1 (cytoplasmic/nuclear) were 87.5%/37.5% and 88.9%/100%, respectively, which are superior to those of p53 (18.8% and 100%). ENO1 has potential as a biomarker to assist in the histopathological detection of TRU subtype ADC cells.

The ongoing COVID-19 pandemic is a major global public health concern. Although rapid point of care testing for detecting viral antigen is important for management the outbreak, none of current antigen detection kits provide a reliable diagnosis due to the lack of a specific monoclonal antibody (mAb) against SARS-CoV-2. In our current study, we produced mAbs exclusively react with SARS-CoV-2 and exhibited no cross-reactivity with other human coronaviruses including SARS-CoV. Molecular modeling revealed that the mAbs bound to epitopes present on the exterior surface of the nucleocapsid, encompassing their scope for detecting SARS-CoV-2 in clinical samples. We further selected the optimal pair of anti-SARS-CoV-2 NP mAbs for designing ELISA and immunochromatographic assay. An integrated bioinformatics analysis revealed that our mAbs could comprehensively detect divergent strains of SARS-CoV-2. Due to the high redundancy and absence of cross-reactivity, our newly developed mAbs would be instrumental for developing reliable diagnosis kits for COVID-19. Funding: This work was supported in part by Japan Agency for Medical Research and Development (AMED, Grant number: JP19fk0108110 and JP20he0522001), and by Health Labour Sciences research grant from The Ministry of Health Labour and Welfare. Conflict of Interest: The authors have no conflicts of interest directly relevant to the content of this article. YY, SK, KS and DA is a current employee of Kanto Chemical Co., Inc. Ethical Approval: This study was approved by the Institutional Review Board of Yokohama City University (IRB No. B200800106), and the protocols used in the study were approved by the ethics committee.

In order to clarify idiopathic interstitial pneumonia (IIP)-associated lung adenocarcinoma (LADC), we herein focused on the expression profiles of mucin proteins, the most common cellular differentiation markers. The expression of the mucin (MUC) 1, MUC2, MUC3B, MUC4, MUC5AC, MUC5B, MUC6, MUC7, MUC9, and MUC21 proteins was examined immunohistochemically and their levels were semi-quantified in 80 IIP-associated LADCs and 106 non-IIP LADCs. LADCs were divided into low and high expressers based on thresholds obtained from the receiver operating characteristic (ROC) curves of each mucin protein. Low expressers of MUC1, MUC7, and MUC21 and high expressers of MUC4, MUC5AC, MUC5B, and MUC9 were dominant in the IIP group. Multivariate analyses confirmed that the correlations between mucin expression profiles and IIP-associated LADCs were independent of putative confounding factors, such as smoking, gender, histological types, and cytological types. Thus, the expression profiles of these mucin proteins significantly differed between the IIP and non-IIP groups. IIP-associated LADCs appear to have unique cellular differentiation features and they may develop through a distinct histogenetic pathway. This is the first study to demonstrate that IIP-associated LADCs have unique mucin expression profiles.

Aims To investigate the pathological features of idiopathic interstitial pneumonia (IIP) - associated pulmonary adenocarcinoma. Methods Surgically resected adenocarcinomas associated with IIP (the IIP group) and adenocarcinomas without IIP (the non-IIP group) were subjected. We here further focused on adenocarcinomas that developed in the honeycomb lesions. Adenocarcinomas in the IIP group were subdivided into two groups, one group included tumors connected to bronchiolar metaplasia in honeycomb lesions (the H-IIP group) and the other included tumors unrelated to honeycomb lesions (the NH-IIP group). Histomorphological appearance, immunohistochemical expression were compared among the H-IIP group, the NH-IIP group, and the non-IIP group. Results Most of tumor cells in the H-IIP group showed tall columnar shape that displayed similar features to proximal bronchial epithelium, while tumors in the NH-IIP group and the non-IIP group showed club-like shape that displayed similar features to respiratory bronchiole /alveolar epithelium. The cell differentiation markers, thyroid transcription factor-1 (TTF-1) and Hepatocyte nuclear factor 4 alpha (HNF- 4α), tended to be negative for TTF-1 and positive for HNF- 4α in adenocarcinomas in the H-IIP group. The frequency of EGFR mutations was significantly lower in adenocarcinomas in the H-IIP group, although the frequency of KRAS and ALK mutations did not differ among the three groups. Conclusions The IIP-associated pulmonary adenocarcinomas, especially those arising from honeycomb lesions, have distinct pathological features. This article is protected by copyright. All rights reserved.

We herein investigated the potential role of cathepsin L in lung carcinogenesis. Lung cancer cell lines and surgically resected tumors were examined for the expression of the cathepsin L protein and copy number alterations in its gene locus. Cathepsin L was stably expressed in bronchiolar epithelial cells. Neoplastic cells expressed cathepsin L at various levels, whereas its expression was completely lost in most of the lung cancer cell lines (63.6%, 7/11) examined. Furthermore, expression levels were lower in a large fraction of lung tumors (69.5%, 139/200) than in bronchiolar epithelia. The expression of cathepsin L was lost in some tumors (16.0%, 32/200). In adenocarcinomas, expression levels were significantly lower in high-grade tumors than in low-grade tumors (one-way ANOVA, P

A normal counterpart and precancerous lesion that non-terminal respiratory unit (TRU) lung adenocarcinomas (LADCs) develop from have not been clarified. Non-TRU LADCs specifically express hepatocyte nuclear factor 4α (HNF4α). Thus, we have been interested in airway epithelial cells that express HNF4α as the potential precursor of non-TRU LADC. The purposes of the present study are to report the frequency and distribution of HNF4α-expressing cells at the different airway levels, and to investigate the potential significance of the expression of HNF4α in the histogenesis of non-TRU LADC with a special reference to the relationship to bronchiolar metaplasia in idiopathic interstitial pneumonia. We herein identified a minor subpopulation of epithelial cells that express HNF4α in a physiological state. This subpopulation was mainly located in the terminal bronchioles and had the appearance of ciliated cells, which were mutually exclusive from Clara cells and others that strongly expressed thyroid transcription factor 1. Furthermore, the expression of HNF4α was similar in bronchiolar metaplastic lesions and the terminal bronchioles, and some of the metaplastic lesions showed an unequivocally higher frequency and expression level of HNF4α, which was comparable to non-TRU LADC. In summary, this is the first study to describe a subpopulation of ciliated cells that express HNF4α as a potential normal counterpart for non-TRU LADCs and suggests that bronchiolar metaplastic lesions that strongly express HNF4α are a precancerous lesion for non-TRU LADCs.

We investigated the significance of MUC21 in EGFR-mutated lung adenocarcinoma (LADC). Two-hundred forty-one surgically resected LADCs (116 EGFR-mutated and 125 wild-type tumors) were examined for immunohistochemical expression of MUC21 protein. A polyclonal antibody and two monoclonal antibodies (heM21C and heM21D) that bind differentially glycosylated MUC21 epitopes were used, and MUC21 proteins detected by these antibodies were named MUC21P, MUC21C, and MUC21D, respectively. MUC21 mRNA levels were semi-quantified and classified into "high" and "low". Among the immunohistochemical expression detected by three different antibodies, high expressors tended to be related to EGFR mutations. The three varieties of the immunohistochemical expressions were related to different histological elements in the EGFR-mutated LADCs. Either MUC21P or MUC21C high expressors had a higher proportion of lepidic elements with low papillary structure and micropapillary elements. MUC21D high expressors had a significantly higher proportion of micropapillary elements (Mann-Whitney test P ≤0.0001). Furthermore, MUC21D high expressors showed high incidence of lymphatic canal invasion and lymph node metastasis (Pearson x2 test, P = 0.0021, P = 0.0125), and a significantly higher recurrence rate (5-year recurrence-free survival 50.7% vs. 73.8%, log-rank test P = 0.0495). MUC21 proteins with a specific glycosylation status may be involved in the progression of EGFR-mutated LADCs, particularly at the stage where tumors are transforming from pure lepidic to micropapillary through low papillary lepidic lesions.

Chemical reactivity of acyl glucuronides (AGs) is believed to be involved in the toxicity of carboxylic acid-containing drugs. Both direct and immune-mediated toxicity have been suggested as possible mechanisms of toxicity; however, it remains unclear. In the present study, we performed assays of half-lives, peptide adducts, and immunostimulation to evaluate the potential risk of AGs of 21 drugs and analyzed the relationship to the toxic category. AGs of all withdrawn drugs tested in this study showed short half-lives and peptide adducts formation, but so did those of several safe drugs. In contrast, only AGs of withdrawn and warning drugs induced interleukin-8 (IL-8) in human peripheral blood mononuclear cells (hPBMCs). Using a DNA microarray assay, we found that zomepirac AG induced the mRNAs of 5 genes, including IL-8 in hPBMCs. In addition, withdrawn and warning drugs were distinguished from safe drugs by an integrated score of relative mRNA expression levels of 5 genes. The immunostimulation assay showed higher sensitivity, specificity, and accuracy compared with other methods. In preclinical drug development, the evaluation of the reactivity of AGs using half-lives and peptide adducts assays followed by the evaluation of immunostimulation by highly reactive AGs using hPBMCs can contribute to improved drug safety.

The expression of microRNA-31 (miR-31) has been implicated in the progression of some human malignancies including colorectal cancer. However, the clinical significance of the expression of miR-31 in submucosally invasive (T1) colorectal cancer remains unclear. The aim of the present study was to delineate the relationship between clinicopathological features and the oncogenic modulator miR-31 in submucosally invasive colorectal cancer. We investigated the expression of miR-31 in 50 submucosally invasive colorectal cancer specimens, along with the corresponding non-tumoral mucosa specimens, using a real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The relationships between miR-31 expression levels and clinicopathological characteristics were assessed. The miR-31 host gene locus was investigated using fluorescence in situ hybridization. qRT-PCR revealed that the expression of miR-31 was higher in colorectal cancer tissue than in non-tumoral tissue (P = 0.0002). The up-regulated expression of miR-31 may play an oncogenic role in the early stage of carcinogenesis in colorectal cancers.

Ciliated muconodular papillary tumors (CMPTs) are a recently categorized benign or low-grade malignant neoplasm that develops in the peripheral lung. Only about 40 cases have been reported to date, and the clinicopathological characteristics have yet to be defined in detail. Here, we present four cases of CMPTs with a focus on their immunohistochemical profiles and driver gene mutations. These tumors were a papillary proliferation of a mixture of ciliated, mucous, and basal cells located in the peripheral lung. Ciliated, mucous and basal cells were positive for TTF-1 when using the clone SPT24, but negative for HNF-4α. Basal cells were positive for p40. Mucous cells in some tumors were positive for MUC5AC and MUC6. The Ki-67 index was less than 5%, and strong expression of p53 was not detected. Three of the four tumors had a BRAF (V600E) driver mutation, an EGFR (del E746-T751/S752V) driver mutation, or driver mutations in both EGFR (E709G) and KRAS (G12V). These mutation types are rare for any histological type of lung cancer. The present results confirmed that CMPT is a neoplasm with immunohistochemical features and driver gene mutations that are distinct from those of common lung tumors.

Lung adenocarcinomas (ADCs) have been roughly divided into two groups: the terminal respiratory unit (TRU) type and non-TRU type. These ADCs appear to develop through exclusive carcinogenetic pathways because of differences in their cellular morphologies and the profiles of protein expression and genetic alterations. The TRU type develops from atypical adenomatous hyperplasia as a precursor. On the other hand, the histogenesis of the non-TRU type has not yet been defined in detail. We herein investigated histopathological changes in the non-tumor lung tissues of patients with non-TRU-type ADCs in order to define their potential histogenesis. The non-TRU type preferentially occurs in patients with interstitial pneumonia, in whom tumors are located in honeycomb lesions and are associated with bronchiolar metaplasia (BM). Among patients without interstitial pneumonia, non-tumor lung tissues from non-TRU-type ADCs were often affected by multiple BM. In these cases, tumors often were associated with BM. Metaplastic cells adjacent to non-TRU-type ADCs ectopically expressed HNF-4α, a marker for non-TRU-type ADCs. These results suggest that the non-TRU type develops through distinct histogenesis, in which BM is implicated.

We herein analyzed the relationships among the immunohistochemical expression of alpha-enolase (ENO1) and clinicopathological factors in order to define the significance of ENO1 in lung adenocarcinomas (ADCs). ENO1 expression was detected in most of the ADCs examined (95.8%), but not in bronchial and alveolar epithelia. ENO1 expression was typically observed in the cytoplasm among most ADCs (95.8%), but was also detected in the nucleus (56.3%). The levels were significantly higher in terminal respiratory unit (TRU) cytological subtype ADCs. Neither cytoplasmic nor nuclear expression was associated with any other clinicopathological factors including post-operative survival and growth activity. These results suggest that ENO1 is a crucial factor promoting neoplastic transformation exclusively in TRU subtype ADCs. We also investigated the potential utility of the immunohistochemical expression of ENO1 to differentiate TRU-type ADC cells from the reactive hyperplasia of pneumocytes and bronchiolar epithelial cells because difficulties are associated with discriminating these lesions in small biopsy specimens. The sensitivity and specificity of ENO1 (cytoplasmic/nuclear) were 87.5%/37.5% and 88.9%/100%, respectively, which are superior to those of p53 (18.8% and 100%). ENO1 has potential as a biomarker to assist in the histopathological detection of TRU subtype ADC cells.

An autopsy case of leptomeningeal melanomatosis associated with neurocutaneous melanosis (NCM) involving a 44-year-old male is reported. The autopsy showed that the leptomeningeal surface of the brain and the spinal cord were covered with a diffuse black lesion. A histological examination detected diffusely distributed, proliferating, melanin-containing cells and demonstrated that the lesion consisted of three different components; i.e. regions of melanomatosis, melanocytosis, and melanocyte hyperplasia. In the leptomeningeal melanomatosis component, tumor cells with pleomorphic nuclei and prominent nucleoli had infiltrated into the cerebral parenchyma via Virchow-Robin spaces. The Ki-67 labeling index and the nuclear accumulation of p53 and p16 protein were immunohistochemically examined in each component. The Ki-67 labeling indices of the melanomatosis, melanocytosis, and melanocyte hyperplasia components were 8.7%, 0.8%, and 0%, respectively. Immunostaining of nuclear p16 produced a negative result in the melanomatosis component, but positive results in the melanocytosis and melanocyte hyperplasia components, whereas nuclear p53 expression was not detected in any of the components. This case suggests that p16(INK4) /CDKN2 may play a significant role in progression of leptomeningeal melanocytic neoplasms. We also reviewed previously reported cases of leptomeningeal neoplasms associated with NCM and discussed the relationship between the biological behavior and proliferative activity of such lesions.

Our previous research suggested that obesity induces structural fragility in the skin. Elastic fibers impart strength and elasticity. In this study, we determined whether elastic fibers decrease in the skin of obese mice.To confirm alterations in elastic fiber content due to obesity, we used spontaneously obese model mice (TSOD) and control mice (TSNO). Furthermore, to evaluate the elastin structure and gene expression dependent on the severity of obesity, an obesity-enhanced mouse model was developed by feeding a high fat diet to TSOD (TSOD-HF). Back skin samples were stained with hematoxylin and eosin and Elastica van Gieson for microscopic examination, and the samples were stained for immunohistochemical analysis of neprilysin. Gene expression levels were determined using a real-time PCR system.The abundance of elastic fibers beneath the epidermis was remarkably reduced and fragmented in TSOD as compared with TSNO. Fibrillin-1 mRNA levels in TSOD were significantly suppressed compared with those in TSNO, whereas neprilysin mRNA levels and immunohistochemical expression in TSOD were significantly increased, as compared with those in TSNO. The reduction of elastic fibers was enhanced and the expression levels of elastic fiber formed factors were significantly suppressed in TSOD-HF, as compared with those in the TSOD.The abundance of elastic fibers was reduced and fragmented in obesity, suggesting that the reduction in elastic fibers is initially caused by increased neprilysin and decreased fibrillin-1 expression, which may inhibit formation and stabilization of elastic fibers, resulting in skin fragility in obesity.

The present study investigated expression profiles of the potential CSC markers including CD133, CD44, ALDH1, and β-catenin, and evaluated their prognostic value in lung adenocarcinomas. One-hundred-and-seventy-seven tumors (stage I) were immunohistochemically examined for the expression of these markers, and thresholds to subdivide expression levels were determined using receiver operating characteristics curves. Tumors with high levels of CD133 (adjusted hazard ratio (HR) 4.55 (95% confidence interval (CI) 1.26-16.40, P = 0.021), CD44 (HR 3.73, 95% CI 1.20-11.58, P = 0.023) or ALDH1 (HR 3.61, 95% CI 1.09-12.3, P = 0.036), but not β-catenin (HR 2.43, 95% CI 0.59-10.8, P = 0.220), showed a significantly higher risk of recurrence than the corresponding low expressers. In conclusion, levels of CD133, CD44, and ALDH1 had independent prognostic value to predict the recurrence of lung adenocarcinoma.

A new classification of adenocarcinoma (ADC) was proposed by the International Association for the Study of Lung Cancer, the American Thoracic Society, and the European Respiratory Society (IASLC/ATS/ERS) in 2011. The present study evaluates its prognostic value in stage I disease of Japanese cases. One-hundred-and-seventy-nine cases with pathological stage I ADC were classified according to the new classification system and their association with disease recurrence was analyzed. Eighteen (10.1%) and 24 (13.4%) cases were adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA), respectively. One-hundred-and-thirty-seven cases (76.5%) were invasive adenocarcinoma (IVA), in which 43 (24.0%) were lepidic (LEP), 59 (33.0%) were acinar (ACN), 16 (8.9%) were papillary (PAP), 1 (0.6%) was micropapillary (MPAP), 12 (6.7%) were solid predominant subtypes (SOL), and 6 (3.4%) were invasive mucinous adenocarcinoma (MUC). The5-year disease-free survivals (DFS) of patients with AIS and MIA were 100%. Those of LEP, ACN, PAP, SOL and MUC were 93.5%, 83.7%, 75.0%, 44.4% and 62.5%, respectively. Multivariate analysis showed that high-histological grade (SOL, MPAP, MUC) had an independent prognostic value to predict post-operative recurrence (HR 3.661, 95% CI 1.421-9.437, P = 0.007). In conclusion, the present study demonstrates a prognostic value of the 2011 IASLC/ATS/ERS classification of ADC in Japanese cases.

The effects of specimen size and location of V-notch on the Charpy impact properties were investigated with different sizes of specimens, standard, CVN-1/2, CVN-1/3, and CVN-1.5 mm, for A533B steel, low Mn, high Cu, high phosphorus (P), and high Cu/P steel weld joint. A part of the specimens was irradiated with neutron at 563 K up to 8 × 1019 n/cm2. The heat affected zone (HAZ) specimen is the best in the impact properties among the specimens of base metal, HAZ, and weld metal in the steels with 0.003 wt.% P, while it is the worst in the steels with ∼ 0.3 wt.% P. This indicates that the surveillance test of HAZ specimen can be represented by base metal in the case of A533B steels with lower P content (∼ 0.003 wt.%). The effects of notch location and chemical contents on ductile to brittle transition temperature (DBTT) are almost independent of specimen size within an error of ±5 K, indicating that the miniaturized Charpy specimens are applicable and effective in the surveillance tests of reactor pressure ...

FXYD3 is a FXYD-containing Na,K-ATPase ion channel regulator first identified as a protein overexpressed in murine breast tumors initiated by oncogenic ras or neu. However, our preliminary study revealed that FXYD3 expression was down-regulated in oncogenic KRAS-transduced airway epithelial cells. This contradiction led us to investigate the role of FXYD3 in carcinogenesis of the lung. FXYD3 mRNA and protein levels were lower in most of the lung cancer cell lines than in either the noncancerous lung tissue or airway epithelial cells. Protein levels were also lower in a considerable proportion of primary lung cancers than in nontumoral airway epithelia; FXYD3 expression levels decreased in parallel with the dedifferentiation process. Also, a somatic point mutation, g55c (D19H), was found in one cell line. Forced expression of the wild-type FXYD3, but not the mutant, restored the well-demarcated distribution of cortical actin in cancer cells that had lost FXYD3 expression, suggesting FXYD3 plays a role in the maintenance of cytoskeletal integrity. However, no association between FXYD3 expression and its promoter's methylation status was observed. Therefore, inactivation of FXYD3 through a gene mutation or unknown mechanism could be one cause of the atypical shapes of cancer cells and play a potential role in the progression of lung cancer.

Our preliminary studies revealed that oncogenic KRAS (KRAS/V12) dramatically suppressed the growth of immortalized airway epithelial cells (NHBE-T, with viral antigen-inactivated p53 and RB proteins). This process appeared to be a novel event, different from the so-called premature senescence that is induced by either p53 or RB, suggesting the existence of a novel tumor suppressor that functions downstream of oncogenic KRAS. After a comprehensive search for genes whose expression levels were modulated by KRAS/V12, we focused on DUSP6, a pivotal negative feedback regulator of the RAS-ERK pathway. A dominant-negative DUSP6 mutant, however, failed to rescue KRAS/V12-induced growth suppression, but conferred a stronger anchorage-independent growth activity to the surviving subpopulation of cells generated from KRAS/V12-transduced NHBE-T. DUSP6 expression levels were found to be weaker in most lung cancer cell lines than in NHBE-T, and DUSP6 restoration suppressed cellular growth. In primary lung cancers, DUSP6 expression levels decreased as both growth activity and histological grade of the tumor increased. Loss of heterozygosity of the DUSP6 locus was found in 17.7% of cases and was associated with reduced expression levels. These results suggest that DUSP6 is a growth suppressor whose inactivation could promote the progression of lung cancer. We have here identified an important factor involved in carcinogenesis through a comprehensive search for downstream targets of oncogenic KRAS.

We herein investigated the potential role of cathepsin L in lung carcinogenesis. Lung cancer cell lines and surgically resected tumors were examined for the expression of the cathepsin L protein and copy number alterations in its gene locus. Cathepsin L was stably expressed in bronchiolar epithelial cells. Neoplastic cells expressed cathepsin L at various levels, whereas its expression was completely lost in most of the lung cancer cell lines (63.6%, 7/11) examined. Furthermore, expression levels were lower in a large fraction of lung tumors (69.5%, 139/200) than in bronchiolar epithelia. The expression of cathepsin L was lost in some tumors (16.0%, 32/200). In adenocarcinomas, expression levels were significantly lower in high-grade tumors than in low-grade tumors (one-way ANOVA, P 0.0500). Copy number alterations were found in 18.0% (36 [32 gain + 4 loss] /200) of lung tumors. No relationship existed between cathepsin L protein expression levels and the copy number of its gene locus (Spearman's rank-order correlation, P = 0.3096). Collectively, these results suggest that the down-regulated expression of cathepsin L, which is caused by an undefined mechanism other than copy number alterations, is involved in the progression of lung adenocarcinomas.

We herein analyzed the relationships between tropomyosin protein expression levels and clinicopathological factors in order to determine the significance of tropomyosins in lung cancers. Although neoplastic cells expressed different isoforms of tropomyosin, overall expression levels were lower than those in bronchial and alveolar epithelial cells. In adenocarcinomas, tropomyosin levels were markedly reduced in poorly differentiated or solid subtype carcinomas, suggesting that a loss in the expression of tropomyosins is involved in the progression of lung adenocarcinomas. The potential utility of the immunohistochemical expression of tropomyosins for a histopathological diagnosis was also investigated. The sensitivity and specificity of a loss in the expression of tropomyosins were 100% and 50%, respectively, which were superior to those for the strong expression of p53 (sensitivity 100% and specificity 44%), a conventional biomarker. An immunohistochemical examination of tropomyosins may assist in the histopathological detection of lung cancer cells in small biopsy specimens.

We previously reported that patients with lung adenocarcinomas with KRAS gene mutations and strong proliferating activity had poorer outcomes, even in the early stage of the disease. The aim of the present study was to elucidate the potential molecular basis of these highly malignant lung tumors by focusing on S100 proteins (S100A2, S100A7, and S100A11), which are downstream targets of oncogenic KRAS and promoters of tumor progression. The immunohistochemical expression of S100 proteins was examined in 179 primary lung adenocarcinomas, and the potential relationships between their levels and clinicopathologic factors were analyzed. Among the three subtypes, S100A11 levels were significantly higher in adenocarcinomas with KRAS mutations and strong proliferating activity. They were also higher in adenocarcinomas with poorly differentiated tumors. Furthermore, higher levels of S100A11 were associated with shorter disease-free survival. These results suggest that the up-regulation of S100A11 plays a role in tumor progression, particularly in KRAS-mutated lung adenocarcinomas.

Exercise-induced acute renal failure (ARF) developed in a 45-year-old man during antihypertensive therapy with losartan and trichlormethiazide. The antihypertensive therapy was stopped and marked hypouricemia became apparent during improvement of his renal function. The daily urinary excretion of uric acid was normal and an increased fractional excretion of uric acid was observed. Renal biopsy revealed that the kidney was recovering from acute tubular necrosis with interstitial fibrosis. Based on the results of pyrazinamide and benzbromarone tests, we classified this case as one of presecretory reabsorption defect of uric acid. Antihypertesive therapy with benidipine and candesartan was initiated, and the patient has not had any ARF episodes since. Because idiopathic renal hypouricemia can be associated with exercise-induced ARF and chronic renal dysfunction, careful antihypertensive therapy and follow-up evaluation of renal function might be necessary for hypertensive patients with idiopathic renal hypouricemia. (Hypertens Res 2003; 26: 509-513)

An autopsy case of leptomeningeal melanomatosis associated with neurocutaneous melanosis (NCM) involving a 44-year-old male is reported. The autopsy showed that the leptomeningeal surface of the brain and the spinal cord were covered with a diffuse black lesion. A histological examination detected diffusely distributed, proliferating, melanin-containing cells and demonstrated that the lesion consisted of three different components; i.e. regions of melanomatosis, melanocytosis, and melanocyte hyperplasia. In the leptomeningeal melanomatosis component, tumor cells with pleomorphic nuclei and prominent nucleoli had infiltrated into the cerebral parenchyma via Virchow-Robin spaces. The Ki-67 labeling index and the nuclear accumulation of p53 and p16 protein were immunohistochemically examined in each component. The Ki-67 labeling indices of the melanomatosis, melanocytosis, and melanocyte hyperplasia components were 8.7%, 0.8%, and 0%, respectively. Immunostaining of nuclear p16 produced a negative result in the melanomatosis component, but positive results in the melanocytosis and melanocyte hyperplasia components, whereas nuclear p53 expression was not detected in any of the components. This case suggests that p16(INK4) /CDKN2 may play a significant role in progression of leptomeningeal melanocytic neoplasms. We also reviewed previously reported cases of leptomeningeal neoplasms associated with NCM and discussed the relationship between the biological behavior and proliferative activity of such lesions.

To elucidate the role of p53 and apoptosis in the pathogenesis of lung injury, we examined histological changes, expressions of p53 and p21waf1/cip1 (p21), apoptosis, DNA double strand breaks, cell kinetics, and DNA synthesis in C57/BL6 mice (p53+/+) and mice deficient for p53 (p53−/−) at 2 hours to 7 days after a single intravenous administration of bleomycin. We also compared these parameters between the lung cells and small intestinal epithelial cells to explore potential differences in their response to DNA damage. Bleomycin induced p21 expression in a p53-dependent manner in p53+/+ mice but neither p53 nor p21 expression in p53−/− mice. In the lung of both groups of mice, focal inflammation followed by fibrosis was observed, but there was no evidence of apoptosis. Cells with DNA breaks and those undergoing DNA synthesis were unequivocally increased, but the cycling cell fraction remained unchanged, suggesting that the DNA synthesis detected in the lung reflected unscheduled DNA synthesis for repair of damaged DNA. DNA breaks and unscheduled DNA synthesis were prolonged in p53−/− mice compared to p53+/+ mice. By contrast, in the small intestine, marked cell cycle arrest and extensive apoptosis were evoked in the cycling crypt cells of both groups of mice, but these changes were milder and DNA breaks remained detectable for a longer time in p53−/− mice than in p53+/+ mice. Among the resting enterocytes in the villi, apoptosis was observed almost equally in both groups, but repair of DNA breaks was significantly delayed in the p53−/− mice. These observations imply that apoptosis is mediated largely by the p53-dependent pathway in the crypts but exclusively by the p53-independent pathway in the villi, that this pathway is particularly important in DNA repair in the villi, and that despite this difference in the significance of apoptosis, p53 plays an important role in DNA repair in both the crypts and villi. Our results suggest that the lung cells and small intestinal cells respond to the bleomycin treatment in different ways in terms of the induction of apoptosis and that p53 carries out an essential role in the early response to and repair of DNA damage by a non-apoptotic mechanism which appears to be crucial in the noncycling lung cells and enterocytes. Importantly, the p53-p21 pathway and apoptosis are unlikely to be essential for bleomycin-induced tissue injury in the lung.

The expression of microRNA-31 (miR-31) has been implicated in the progression of some human malignancies including colorectal cancer. However, the clinical significance of the expression of miR-31 in submucosally invasive (T1) colorectal cancer remains unclear. The aim of the present study was to delineate the relationship between clinicopathological features and the oncogenic modulator miR-31 in submucosally invasive colorectal cancer. We investigated the expression of miR-31 in 50 submucosally invasive colorectal cancer specimens, along with the corresponding non-tumoral mucosa specimens, using a real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The relationships between miR-31 expression levels and clinicopathological characteristics were assessed. The miR-31 host gene locus was investigated using fluorescence in situ hybridization. qRT-PCR revealed that the expression of miR-31 was higher in colorectal cancer tissue than in non-tumoral tissue (P = 0.0002). The up-regulated expression of miR-31 may play an oncogenic role in the early stage of carcinogenesis in colorectal cancers.

Small non-protein coding RNAs that regulate messenger RNA levels, namely microRNAs (miRNAs), have been implicated in the pathogenesis of various diseases. The purpose of the present study was to identify essential miRNAs involved in lung carcinogenesis. Previous studies demonstrated that an investigation into the downstream targets of oncogenic KRAS could be used as a strategy to elucidate the molecular mechanisms involved in lung cancer; therefore, we examined the expression profiles of mRNAs modulated by oncogenic KRAS in the present study. We focused on miR-31 from the miRNAs that were differentially expressed, and evaluated its potential role in the development of lung cancer. miR-31 was upregulated not only by oncogenic KRAS, but also by oncogenic EGFR. The expression of miR-31 was markedly attenuated in some lung cancer cell lines by deleting its host gene locus. The restoration of miR-31 in lung cancer cell lines that lost its expression attenuated their growth activities. The knockdown of miR-31 expression in lung cancer cell lines retaining its expression enhanced anchorage-independent growth activity. These results suggest that miR-31 may be a suppressor that regulates an essential oncogenic pathway, the loss of which may promote lung carcinogenesis.

Polycrystalline and single-crystalline 3C silicon carbide films hetero-epitaxially grown on 3′' or 4′' Si wafers have been obtained by a hotwall type low-pressure chemical-vapour deposition (LPCVD). The internal stress of the polycrystalline film can be adjusted from 30 to 250 MPa (tensile) by changing the growth parameters, while that of the single crystal ranges from 100 to 200 MPa (tensile). The stress uniformity of the 46 mm2 polycrystalline membrane is measured to be ±9.7%, while that of the single one is ±3.0%. The biaxial Young's modulus is around 450 GPa for both the films and the burst strength for a 2.0 μm thick 20 mm2 polycrystalline membrane is about 0.4 kgf cm−2. Optical transparencies of 1.0 μm thick membranes are 70 and 80% at 633 nm for the polycrystal and the single crystal, respectively. The single crystal always shows higher transmission over the wavelength range studied and an extended absorption edge to the shorter wavelengths. The current values of mobility, carrier density and resistivity of the single crystal are roughly 180 cm2 V−1 s−1, 2 × 1018 cm−3 and 0.02 Ω cm, respectively.

The present study evaluated the potential clinicopathologic significance of elevated microsatellite alteration at selected tetra-nucleotide (EMAST) in non-small cell lung cancer (NSCLC). Sixty-five NSCLCs (19 squamous cell carcinomas, 39 adenocarcinomas, one adenosquamous cell carcinoma, and 6 large cell carcinomas) were examined for EMAST in the ten selected tetra-nucleotide markers. Traditional microsatellite instability (MSI) in the five mono- or di-nucleotide markers of the Bethesda panel was also examined, and compared with EMAST. The incidence of EMAST was higher than that of traditional MSI, as 64.6% (42/65) and 12.3% (8/65) tumors respectively exhibited EMAST and traditional MSI in at least one marker. EMAST and traditional MSI appear to occur independently, as no significant association in their incidence was found (Fisher’s exact test, P = 0.146). Subjects who exhibited EMAST in two or more markers had a significantly higher incidence of history of other malignant neoplasms (42.9% [9/21]), compared to those with less than two markers (16.3% [7/43] (Chi-square test, P = 0.021)). Taken together, impairment of molecular machinery for maintaining stable replication of the tetra-nucleotide-repeating regions, which would differ from machinery for mono- or di-nucleotide-repeating regions, may elevate susceptibility to NSCLCs and certain neoplastic diseases. Elucidation of the potential molecular mechanism of EMAST is expected to lead to a discovery of a novel genetic background determining susceptibility to NSCLC and other multiple neoplasms. This is the first report describing a clinicopathologic significance of EMAST in NSCLC.

ALDH1A1 metabolizes a variety of endogenous and exogenous aldehyde, and also oxidizes retinol to synthesize retinoic acid and modulate cell differentiation. Moreover, ALDH1A1 is also suggested to participate in the maintenance of cancer stem cells. To investigate the potential role of ALDH1A1 in carcinogenesis of the lung, the present study examined two hundred and sixty eight cases of non-small cell lung carcinoma (NSCLC) for its immunohistochemical expression and analyzed associations between ALDH1A1 levels and a series of clinicopathologic parameters. Also, the biological significance of the aberrant expression of ALDH1A1 was investigated in vitro. ALDH1A1 expression was markedly reduced in 39.9% (107/268) of NSCLCs. The incidence of this reduction was significantly higher in adenocarcinomas (ADC: 41.6%, 85/207) and large cell carcinomas (61.1%, 11/18) than squamous cell carcinomas (25.5%, 11/43). Among ADCs, the downregulation tended to be more remarkable in high grade, poorly differentiated tumors, and tumors with stronger proliferating activity. It also occurred with a significantly higher incidence in smokers than non-smokers. Forced expression of ALDH1A1 in NSCLC cell lines, which had lost ALDH1A1 expression, markedly attenuated their growth. Taken together, loss of ALDH1A1 expression is suggested to promote carcinogenesis especially in the smoking-related ADCs.