Overexpression of AQP3 Modifies the Cell Cycle and the Proliferation Rate of Mammalian Cells in Culture

PLoS One. 2015 Sep 14;10(9):e0137692. doi: 10.1371/journal.pone.0137692. eCollection 2015.

Abstract

Abnormal AQP3 overexpression in tumor cells of different origins has been reported and a role for this enhanced AQP3 expression in cell proliferation and tumor processess has been indicated. To further understand the role AQP3 plays in cell proliferation we explore the effect that stable over expression of AQP3 produces over the proliferation rate and cell cycle of mammalian cells. The cell cycle was analyzed by flow cytometry with propidium iodide (PI) and the cell proliferation rate measured through cell counting and BrdU staining. Cells with overexpression of AQP3 (AQP3-o) showed higher proliferation rate and larger percentage of cells in phases S and G2/M, than wild type cells (wt). Evaluation of the cell response against arresting the cell cycle with Nocodazole showed that AQP3-o exhibited a less modified cell cycle pattern and lower Annexin V specific staining than wt, consistently with a higher resistance to apoptosis of AQP3-overexpressing cells. The cell volume and complexity were also larger in AQP3-o compared to wt cells. After transcriptomic analysis, RT-qPCR was performed to highlight key molecules implicated in cell proliferation which expression may be altered by overexpression of AQP3 and the comparative analysis between both type of cells showed significant changes in the expression of Zeb2, Jun, JunB, NF-kβ, Cxcl9, Cxcl10, TNF, and TNF receptors. We conclude that the role of AQP3 in cell proliferation seems to be connected to increments in the cell cycle turnover and changes in the expression levels of relevant genes for this process. Larger expression of AQP3 may confer to the cell a more tumor like phenotype and contributes to explain the presence of this protein in many different tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aquaporin 3 / biosynthesis*
  • Aquaporin 3 / genetics
  • Cell Cycle Checkpoints / drug effects
  • Cell Cycle Checkpoints / genetics
  • Cell Division*
  • G2 Phase*
  • Gene Expression Regulation, Neoplastic*
  • Neoplasm Proteins / biosynthesis*
  • Neoplasm Proteins / genetics
  • Neoplasms / genetics
  • Neoplasms / metabolism*
  • Neoplasms / pathology
  • Nocodazole / pharmacology
  • PC12 Cells
  • Rats
  • S Phase*

Substances

  • Aqp3 protein, rat
  • Neoplasm Proteins
  • Aquaporin 3
  • Nocodazole

Grants and funding

The authors thank “Junta de Andalucía, Consejería de Innovacion Ciencia y Empresa” for the postdoctoral contract that supported AGC and “Red de Terapia Celular” for the postdoctoral contract that supported RRL. This work was funded by grants from the “Instituto de Salud Carlos III” (Exp. PI12/01882 and Exp. PS09/00605), and by grants from “La Junta de Andalucía, Consejería de Innovación Ciencia y Empresa” (P08-CTS-03574) and Consejería de Salud (PI0018-2014) to RRL and (PI0298-2010) to ME. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.