ORIGINAL ARTICLE   

Minerva Pneumologica 2018 March;57(1):7-15

DOI: 10.23736/S0026-4954.17.01810-7

Copyright © 2017 EDIZIONI MINERVA MEDICA

language: English

miRNA expression in pulmonary adenocarcinomas and squamous cell carcinomas

Melanie DEMES ^{1, 2}, Annette FISSELER-ECKHOFF ^{1, 2} ✉

¹ Group Practice of Pathology, Wiesbaden, Germany; ² Department of Pathology and Cytology, Dr. Horst-Schmidt-Hospital GmbH, Wiesbaden, Germany

BACKGROUND: Lung cancer is one of the leading causes of cancer mortality in men and woman worldwide. An early diagnosis of pulmonary cancer is important but currently most cases are detected at advanced stages. Therefore, the prognosis is one of the poorest of all types of cancers. Pulmonary malignancies are divided into two main histological differentiated groups, non-small cell lung cancer and small-cell lung cancer. Adenocarcinomas and squamous cell carcinomas are subtypes of the non-small cell lung cancer group. Additionally, adenocarcinomas show distinct predominant growth patterns. A histological differentiation is essential for an appropriate individual therapy and prognosis. In addition to immunohistochemical stainings, other molecular markers may be a helping tool for histological subtyping. microRNAs which are small non-coding molecules are known to play a key role in tumorigenesis.
METHODS: In this article, eight miRNAs (miR-20b, miR-21, miR-93, miR-99b, miR-146, miR-155, mR-205 and miR-221) were analyzed in 135 NSCLC tissue samples as a potential differential diagnostic tool for lung cancer pathology. The quantitative real-time polymerase chain reaction with the application of two endogenous controls, miR-16 and U45, was the method of choice.
RESULTS: A correlation between the miR-93 expression and the presence of intranodal metastases was found (P=0.051). miR-21, miR-205 and miR-221 showed an elevated x-fold expression in both adenocarcinoma and squamous cell carcinoma histologies. An addition to the miR-21 expression value (P=3.9*10-5), the x-fold expression of miR-205 (P=2.43*10-22) and miR-221 (P=6.9*10-5) differed significantly between adenocarcinomas and squamous cell carcinomas.
CONCLUSIONS: It can be concluded that miR-205 and miR-221 are supporting markers for the histological assessment and finally differentiation of pulmonary carcinomas.

KEY WORDS: Carcinoma, non-small-cell lung - MicroRNAs - Real-time polymerase chain reaction