miR-375 Affects the Proliferation, Invasion, and Apoptosis of HPV16-Positive Human Cervical Cancer Cells by Targeting IGF-1R

Int J Gynecol Cancer. 2016 Jun;26(5):851-8. doi: 10.1097/IGC.0000000000000711.

Abstract

Objective: The aim of this study was to examine the relationship between miR-375 expression and the proliferation, apoptosis, and migration of cervical cancer cells. To further explore the potential target gene of miR-375, insulin-like growth factor 1 receptor (IGF-1R) was detected in miR-375 overexpressed and inhibited cervical cancer cells, which clarified the potential mechanism of miR-375 in the growth and development of cervical cancer.

Methods: In a cervical cancer cell line (Caski), miR-375 overexpression and knockdown were achieved by transfection with a synthetic miR-375 mimic or miR-375-targeting inhibitor oligonucleotides, respectively, using siRNA-Mate transfection reagents. Real-time Polymerase Chain Reaction was performed to detect the expression level of miR-375. The functional effects of miR-375 on cell proliferation, migration, and apoptosis were evaluated using a Cell Counting Kit (CCK-8) and through scratch wound tests and apoptosis assays, respectively. Western blotting was performed to detect the expression level of the IGF-1R protein.

Result: Transfection with the miR-375 mimic significantly upregulated the expression of miR-375 by approximately 7.76-fold (P < 0.05), reduced cell proliferation and migration (P < 0.05), increased apoptosis (P < 0.05), and decreased the expression of the IGF-1R protein by 24.73% (P < 0.05) compared with the negative control. In contrast, transfection of the miR-375 inhibitor decreased the expression of miR-375 by 14.39% (P < 0.05), significantly increased cell proliferation and migration (P < 0.05), significantly reduced the cell apoptosis (P < 0.05), and upregulated the expression of the IGF-1R protein by 2.29-fold (P < 0.05). The cells transfected with the negative control showed no significant changes compared with the blank control for each parameter (P > 0.05).

Conclusions: miR-375 plays an important role in the tumorigenesis and development of cervical cancer. IGF-1R might represent a target gene of miR-375 in cervical cancer.

MeSH terms

  • Apoptosis / physiology
  • Cell Line, Tumor
  • Cell Movement / physiology
  • Cell Proliferation / physiology
  • Female
  • Gene Knockdown Techniques
  • Human papillomavirus 16 / isolation & purification*
  • Humans
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / biosynthesis
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasm Invasiveness
  • Papillomavirus Infections / genetics
  • Papillomavirus Infections / metabolism*
  • Papillomavirus Infections / pathology
  • Papillomavirus Infections / virology
  • Receptor, IGF Type 1 / genetics
  • Receptor, IGF Type 1 / metabolism*
  • Uterine Cervical Neoplasms / genetics
  • Uterine Cervical Neoplasms / metabolism*
  • Uterine Cervical Neoplasms / pathology
  • Uterine Cervical Neoplasms / virology

Substances

  • MIRN375 microRNA, human
  • MicroRNAs
  • Receptor, IGF Type 1