Browsing by Subject "Tropomyosin"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    Open Access
    Expression of tropomyosins in lung cancer - a potential role in carcinogenesis and its utility in a histopathological diagnosis
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Okudela, Koji; Mitsui, Hideaki; Woo, Tetsukan; Kojima, Yoko; Matsumura, Mai; Arai, Hiromasa; Suzuki, Takehisa; Umeda, Shigeaki; Saito, Yuichi; Tajiri, Michihiko; Masuda, Munetaka; Kameda, Yoichi; Ohashi, Kenichi
    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.
  • Thumbnail Image
    Publication
    Open Access
    Tropomyosin 2 exerts anti-tumor effects in lung adenocarcinoma and is a novel prognostic biomarker
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2023) Duan, Peng; Cui, Jing; Li, Hongyan; Yuan, Lei
    Background. Tropomyosin 2 (TPM2), a member of the actin filament binding protein family, plays distinct roles in the progression of different cancer types. Until now, there has been no study reporting TPM2 expression nor its function in lung adenocarcinoma (LUAD). Methods. In the present study, we examined the expression profile of TPM2 by immunohistochemistry (IHC). The clinical significance of TPM2 was assessed by univariate and multivariate analyses. Function of TPM2 in LUAD was evaluated by knockdown and overexpression strategies in three LUAD cell lines, followed by proliferation and invasion assays. Xenografts were conducted in nude mice to further validate the tumor-related role of TPM2. Results. Our results showed that TPM2 was downregulated in LUAD specimens and the low expression of TPM2 was associated with poor outcomes of LUAD patients. Overexpressing TPM2 inhibited cell proliferation and invasion of LUAD cell lines, while silencing TPM2 exerted the opposite effects. The effects of TPM2 in LUAD were further confirmed by xenograft assays. Conclusions. Our results indicated that TPM2 exerted an anti-oncogenic role in LUAD via inhibiting tumor progression, thus providing a novel dire