ElsevierActa Medica Okayama1936-52331412021PRRX1 promotes malignant properties in human osteosarcoma100960ENRyojiJokoDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesDaisukeYamadaDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMasahiroNakamuraPrecision Health, Department of Bioengineering, Graduate School of Engineering, The University of TokyoAkiYoshidaDepartment Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesShotaTakihiraDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTomokaTakaoDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesMingLuDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesKoheiSatoDepartment Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTatsuoItoDepartment of Hygiene, Kawasaki Medical SchoolToshiyukiKunisadaDepartment Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesEijiNakataDepartment Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshifumiOzakiDepartment Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesTakeshiTakaradaDepartment of Regenerative Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesPaired related homeobox 1 (PRRX1) is a marker of limb bud mesenchymal cells, and deficiency of p53 or Rb in Prrx1-positive cells induces osteosarcoma in several mouse models. However, the regulatory roles of PRRX1 in human osteosarcoma have not been defined. In this study, we performed PRRX1 immunostaining on 35 human osteosarcoma specimens to assess the correlation between PRRX1 level and overall survival. In patients with osteosarcoma, the expression level of PRRX1 positively correlated with poor prognosis or the ratio of lung metastasis. Additionally, we found PRRX1 expression on in 143B cells, a human osteosarcoma line with a high metastatic capacity. Downregulation of PRRX1 not only suppressed proliferation and invasion but also increased the sensitivity to cisplatin and doxorubicin. When 143B cells were subcutaneously transplanted into nude mice, PRRX1 knockdown decreased tumor sizes and rates of lung metastasis. Interestingly, forskolin, a chemical compound identified by Connectivity Map analysis using RNA expression signatures during PRRX1 knockdown, decreased tumor proliferation and cell migration to the same degree as PRRX1 knockdown. These results demonstrate that PRRX1 promotes tumor malignancy in human osteosarcoma.No potential conflict of interest relevant to this article was reported.ElsevierActa Medica Okayama2405-8440652020Impact of heavy rains of 2018 in western Japan: disaster-induced health outcomes among the population of Innoshima Islande03942ENSrinivasBandaruDepartment of Public Health, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesShunjiSanoDepartment of Surgery, Division of Pediatric Cardiothoracic Surgery, University of California San FranciscoYurikaShimizuDepartment of Public Health, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesYukaSekiDepartment of Public Health, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesYoshikazuOkanoHitz Hitachi Zosen Health Insurance Association Clinic at InnoshimaTamakiSasakiDepartment of Nephrology & Hypertension, Kawasaki Medical SchoolHidehoWadaDepartment of Hematology, Kawasaki Medical SchoolTakemiOtsukiDepartment of Hygiene, Kawasaki Medical SchoolTatsuoItoDepartment of Public Health, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesSouthwestern Japan suffered its worst rains in 2018 causing floods and mudslides, claiming 225 lives and forcing millions for evacuations. Referred as "Heisei san-ju-nenshichi-gatsugou", the disaster was the result of incessant precipitation caused by the interaction of typhoon "Prapiroon" with the seasonal rain front "Baiu". The present epidemiological study aims to investigate disaster-induced health issues in 728 residents of Innoshima island in the Hiroshima Prefecture by comparing their clinical data in pre-disaster (2017) and disaster-hit (2018) years which was obtained from annual health screening. Comparison of data showed a significant increase in the urine protein concentration in victims following the disaster. Probing further into the household conditions, showed that a total of 59,844 households were affected with water outage during the heavy rains, which was accompanied by severe damage of sewerage pipelines with complete recovery process taking two weeks. This two weeks of the crisis forced victims to refrain from using restrooms which in turn led to infrequent urination, thereby explaining the increased urine protein concentration in victims following the disaster. The present study addresses the acute health implications caused by the water crisis and serves as a precautionary measure for disaster management council to provide enhanced aftercare services in victims in further events of natural disasters. No potential conflict of interest relevant to this article was reported.