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Small cell lung cancer (SCLC) is a severe malignancy associated with early and widespread metastasis. To study SCLC metastasis, we previously developed an orthotopic transplantation model using the human SCLC cell line DMS273. In the model, metastatic foci were found in distant tissues such as bone and the adrenal gland, similarly as observed in patients with SCLC. In this study, we evaluated the differentially expressed genes between orthotopic and metastatic tumors in the model. We isolated tumor cells from orthotopic and metastatic sites, and the tumor cell RNA was analyzed using DNA microarray analysis. We found that 19 genes in metastatic tumors were upregulated by more than 4-fold compared with their expression in orthotopic tumors. One of these genes encodes a transmembrane protein, interferon (IFN)-induced transmembrane protein 1 (IFITM1), and immunohistochemical analysis confirmed the higher expression of the protein in metastatic sites than in orthotopic sites. IFITM1 was also detected in some SCLC cell lines and lung tumors from patients with SCLC. The overexpression of IFITM1 in DMS273 cells increased their metastatic formation in the orthotopic model and in an experimental metastasis model. Conversely, the silencing of IFITM1 suppressed metastatic formation by DMS273 cells. We also found that IFITM1 overexpression promoted the metastatic formation of NCI-H69 human SCLC cells. These results demonstrate that IFITM1 promotes distant metastasis in xenograft models of human SCLC.

Osteoblast and adipocyte are differentiated from mesenchymal stem cells and dysregulation of the differentiation might result in disease, such as osteoporosis and diabetes. To find small compounds that induce osteoblast differentiation, we screened an in-house natural compounds library with mouse preosteoblastic MC3T3-E1 cells using alkaline phosphatase (ALP) expression as an early osteoblast marker. We found that phenazine-1-carboxylic acid (PCA), one of the major phenazine derivatives produced by Pseudomonas, induced osteoblast differentiation in the cells at micromolar concentrations. PCA acted synergistically with an agonist of hedgehog signaling in inducing ALP activity in the cells. We also found that 2-hydroxy-PCA (2H-PCA) induced osteoblast differentiation in the cells but 2-methoxy-PCA and 1-hydroxy-phenazine did not. Unexpectedly, treatment of mouse pluripotent mesenchymal C3H10T1/2 cells with PCA or 2H-PCA induced an obvious morphological change. Oil Red O staining and real-time reverse-transcription PCR analysis revealed that PCA induced not osteoblast differentiation but adipocyte differentiation in C3H10T1/2 cells. These compounds could allow us to investigate the mechanism of osteoblast and adipocyte differentiation in the two model cell systems through a chemical biology approach.

Background: A growing body of pieces of evidence suggests that sport activity is of potential importance both for physical and mental health. To date, there is a lack of information and evidence regarding the mental health of visually impaired people playing some extent of sports and recognized as athletes with renowned career track. The present study aims to clarify the mental health status and its related factors in visually impaired athletes. Methods: The current study was a questionnaire-based cross-sectional investigation. Visually impaired athletes (n = 81; men: 72.8%; average age: 32.8 ± 12.0 years) engaged in Paralympic sports events namely track and field (marathon), goalball, swimming, blind soccer, and judo were the study subjects from leading institutions in Japan. A diverse range of issues were included in a questionnaire survey like attributes, condition of visual impairment, competition activities, competition stressors, social support, and mental health status (recorded through the K6 scale). Logistic regression analyses were performed with mental health status as a dependent variable and other studied parameters as independent variables. Results: A total of 21.0% of study participants (11.9% of men and 45.5% of women) showed bad mental health condition. Results of multivariate logistic regression analysis showed that “female” (odds ratio (OR) 11.94, 95% confidence interval (CI) 2.60 - 54.76, P = 0.001), “higher evaluation from one’s surroundings for competition stressors” (OR 5.74, 95% CI 1.34 - 24.60, P = 0.019), and “lower social support from family members” (OR 3.97, 95% CI 1.03 - 15.25, P = 0.045) were the risk factors of bad mental health. Conclusions: The mental health status among visually impaired athletes might be almost the same level as non-visually impaired athletes and general population, and have relation to gender, stress of evaluation from surroundings during competition, and social support from family members. It may be necessary to pay attention especially to women, and improve one’s surroundings of competition stressors and family social support to maintaining the mental health of visually impaired athletes. J Clin Med Res. 2019;11(11):729-739 doi: https://doi.org/10.14740/jocmr3984

Small cell lung cancer (SCLC) is a severe malignancy with early and widespread metastasis, and novel therapeutic drugs are needed. To identify cytotoxic natural compounds against SCLC, we screened libraries of microbial fermentation broths using several lung cancer cell lines. We found that the actinomycete strain MG372-hF19 produces a compound that has not been isolated from natural sources but previously chemically synthesized, 6-chloro-1H-indole-3-carboxaldehyde (1), and an entirely new compound, named 6-deoxy-α-L-talopyranose 1-(6-chloro-1H-indole-3-carboxylate) (2), together with leptomycins. The molecular formulas of the compounds were established as C9H6ClNO and C15H16ClNO6, respectively, via high-resolution electrospray ionization mass spectrometry, and their structures were determined using detailed NMR. Absolute configurational analysis of the sugar unit of compound 2 revealed that the compound incorporates the rare deoxyhexose 6-deoxy-α-L-talopyranose. Both compounds exhibited weak growth-inhibiting activities against human lung cancer cell lines.

Small-cell lung cancer (SCLC) is an aggressive cancer with high metastatic ability and novel strategies against the metastasis are urgently needed to improve SCLC treatment. However, the mechanism of metastasis of SCLC remains largely to be elucidated. For further studies of SCLC metastasis, we developed a new orthotopic transplantation model in mice. We established a GFP-labeled subline from the human SCLC cell line DMS273 and transplanted them orthotopically into the lung of nude mice with Matrigel. The GFP-labeled cells showed significant metastatic activity and formed metastatic foci in distant tissues such as bone, kidney, and brain, as observed in SCLC patients. From a bone metastasis focus of the mouse, we isolated another subline, termed G3H, with enhanced metastatic potential and higher hepatocyte growth factor (HGF) expression than the parental line. Further studies indicated that the HGF/MET signaling pathway was involved in in vitro motility and invasion activities of the G3H cells and treatments with MET inhibitors decreased formation of distant metastases in our orthotopic model using G3H cells. These data indicated that our model mimics the clinical aspect of SCLC such as metastatic tropism and autocrine of HGF/MET signaling. Compared with other orthotopic SCLC models, our model has a superior ability to form distant metastases. Therefore, our model will provide a valuable tool for the study of SCLC metastasis.