Upregulation of microRNA-31 associates with a poor prognosis of malignant pleural mesothelioma with sarcomatoid component

Our plain-English summary of Upregulation of microRNA-31 associates with a poor prognosis of malignant pleural mesothelioma with sarcomatoid component, by S. Matsumoto, K. Nabeshima, M. Hamasaki, et al (Medical Oncology, 2014).

The study

• Authors: S. Matsumoto, K. Nabeshima, M. Hamasaki, T. Shibuta, T. Umemura
• Journal: Medical Oncology
• Published: 2014;31(12):303
• Cited by: 29 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Malignant pleural mesothelioma (MPM) is a neoplastic disease with a poor prognosis. The complete resection of tumor with extra-pleural pneumonectomy is effective only for early stage epithelioid-type MPM. An accurate pathological diagnosis including the histological subtype and also clinical staging are crucial to decide on the therapeutic approach. However, the pathological diagnosis is difficult when the amount of biopsy sample is small. We performed a comparative analysis of the miR-31 expression in MPM and reactive mesothelial proliferations (RMPs), by RT-qPCR of formaldehyde-fixed paraffin-embedded samples, and compared the expression levels of miR-31 with the results of a survival analysis for the diagnosis and prognosis of MPM. The expression of miR-31 was found to be significantly reduced in MPMs compared with RMPs (P < 0.01). The pathological subtype of four among five cases with upregulated miR-31 levels was MPM with a sarcomatoid component. (i.e., biphasic or sarcomatoid type). Furthermore, these four cases were significantly associated with a worse prognosis compared with the five cases of biphasic or sarcomatoid MPM without upregulated miR-31 expression (P = 0.0027). In conclusion, the analysis of miR-31 expression levels may be a good biomarker for diagnosis of MPM histological typing and predicting the prognosis.

In plain English

This laboratory study from Japan measured a small genetic regulator called microRNA-31 (miR-31) in stored tissue samples. The authors tested tissue from 25 patients with malignant pleural mesothelioma (16 epithelioid, five sarcomatoid, four biphasic). For comparison they used 20 patients with reactive mesothelial proliferations, a non-cancerous condition, associated with bullae. The study did not measure asbestos exposure. On average, miR-31 levels were significantly lower in the mesothelioma samples (0.14, plus or minus 1.07) than in the comparison samples (0.90, plus or minus 0.37; p less than 0.01), although levels varied widely. Five mesothelioma cases had raised miR-31, and four of these had a sarcomatoid component (biphasic or sarcomatoid type). These five patients had a mean survival of 5.3 months, significantly shorter than the other two groups (30.1 and 27.3 months). Among the nine biphasic or sarcomatoid cases, the four with raised miR-31 had a mean survival of 2.3 months, compared with 8.7 months for the other five (P = 0.0027). The authors concluded that miR-31 testing may have a potential role as a biomarker for subtype diagnosis and prognosis. They called for larger studies.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Laboratory study of archived tissue samples comparing mesothelioma with a non-cancerous control condition, with a survival analysis
• Who was studied: 25 patients with malignant pleural mesothelioma (22 males, three females; mean age 65.7 years, range 45 to 85; 16 epithelioid, five sarcomatoid, four biphasic). Controls were 20 patients with reactive mesothelial proliferations associated with bullae (all males; mean age 34.5 years, range 18 to 78). All came from the files of Fukuoka University Hospital, Japan. Dates are not given.
• Exposure: No asbestos exposure was assessed. The factor studied was the level of microRNA-31 (miR-31) in tumor and control tissue.
• Main results:
  • Relative miR-31 levels were significantly lower in mesothelioma tissue (0.14, plus or minus 1.07) than in reactive mesothelial proliferation tissue (0.90, plus or minus 0.37; P less than 0.01).
  • The 25 mesothelioma cases were grouped by miR-31 level: 16 downregulated, 4 normal, 5 upregulated. Eleven of the 16 downregulated cases and all 4 normal cases were epithelioid type.
  • Four of the five upregulated cases (80 %) were mesothelioma with a sarcomatoid component (biphasic or sarcomatoid type).
  • The upregulated group had a mean overall survival of 5.3 months. This was significantly shorter than the normal group (mean 30.1 months; P = 0.047) and the downregulated group (mean 27.3 months; P less than 0.001). The normal and downregulated groups did not differ significantly (P = 0.845).
  • Across all 25 patients, the biphasic and sarcomatoid types had significantly worse survival than the epithelioid type (epithelioid vs. biphasic P = 0.0064; epithelioid vs. sarcomatoid P less than 0.0001).
  • Among the nine biphasic and sarcomatoid cases, the four with upregulated miR-31 had a mean overall survival of 2.3 months, compared with 8.7 months for the other five (P = 0.0027).
• The authors' conclusion: The authors concluded that measuring miR-31 in stored tissue samples may have a potential role as a biomarker for distinguishing mesothelioma subtypes and as a prognostic index.
• Limitations the authors state:
  • miR-31 levels varied widely among cases, and the changes were not consistent. The findings differed from some earlier studies.
  • Differing amounts of normal tissue in each specimen may have caused the wide variation in miR-31 levels.
  • The authors said a larger number of clinical samples is needed, with careful separation of tumor from surrounding normal tissue.
  • The authors said direct confirmation on tissue sections by in situ hybridization is also required.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Prognosis, Pleural Mesothelioma, Sarcomatoid, Pneumonectomy, Epithelioid, Histological Subtype, Staging, Biopsy.

Related studies

• MicroRNA expression in lung tissues of asbestos-exposed mice: Upregulation of miR-21 and downregulation of tumor suppressor genes Pdcd4 and Reck — Y. Hiraku, J. Watanabe, et al. (2021)
• Sarcomatoid mesothelioma: future advances in diagnosis, biomolecular assessment, and therapeutic options in a poor-outcome disease — D. Galetta, A. Catino, et al. (2016)
• MicroRNA signature of malignant mesothelioma with potential diagnostic and prognostic implications — S. Busacca, S. Germano, et al. (2010)
• miR-1254 and miR-574-5p: serum-based microRNA biomarkers for early-stage non-small cell lung cancer — K.M. Foss, C. Sima, et al. (2011)
• B7-H1 expression in malignant pleural mesothelioma is associated with sarcomatoid histology and poor prognosis — A.S. Mansfield, A.C. Roden, et al. (2014)
• Downregulated microRNAs in the differential diagnosis of malignant pleural mesothelioma — G.V. Gee, D.C. Koestler, et al. (2010)

Browse more research in Medical Oncology, or return to medical research.