MiR-210 and miR-152 and their targets proteins as biomarkers by liquid biopsy in breast cancer

Author(s)

Beatriz Camargo Lopes

• Document type: Master's Dissertation
• Press: São José do Rio Preto. 2019-03-26.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências Letras e Ciências Exatas. São José do Rio Preto
• Defense date: 2019-02-25
• Advisor: Debora Aparecida Pires de Campos Zuccari

Abstract

BACKGROUND: The high mortality of breast cancer (BC) is related to the occurrence of metastasis, a process that depends on angiogenesis. The detection of circulating microRNAs by liquid biopsy, as a highlight for miR210 and miR-152 in BC, is of great importance for the determination of early diagnosis and prognosis and, thus, may contribute to decrease BC mortality. OBJECTIVE: To identify and validate microRNAs as noninvasive circulating biomarkers in the diagnosis and prognosis of BC patients and to confirm their performance in angiogenesis. MATERIALS AND METHODS: Tumor fragments and plasma samples were collected from 30 women with BC, five with benign breast conditions and five of women controls. Expression of the microRNAs was performed by RT-qPCR and the analysis of target protein expression by immunohistochemistry. Values of p <0.05 were considered significant. RESULTS: As expected, there was an increase in oncomiR-210 expression and a decrease in miR-152 suppressor in BC tumor fragments. In the BC plasma samples, both miRNAs were increased. Finally, it was found that the HIF-1α, IGF-1R and VEGF proteins showed increased BC expression, whereas the VHL protein showed decrease. CONCLUSION: In conclusion, increase expression of miR-210 and decrease of miR-152 tumor suppressor in BC fragments was observed, validated by the expression of their target proteins involved in angiogenesis. Furthermore, the increased expression of both miRNAs by liquid biopsy of women with BC is promising in the diagnosis and prognosis of this neoplasm, making them potential biomarkers, in addition to the benefit of being detected by a minimally invasive tool. (AU)

• FAPESP's process: 17/11807-3 - Signatures of circulating microRNAs in diagnosis and prognosis of women with breast cancer
• Grantee: Beatriz Camargo Lopes
• Support Opportunities: Scholarships in Brazil - Master