Ovarian cancer: Ion channel and aquaporin expression as novel targets of clinical potential

Down-regulated aquaporin 5 inhibits proliferation and migration of human epithelial ovarian cancer 3AO cells

Background

Recent studies suggested that aquaporins 5 (AQP5) was associated with many kinds of cancers and regulated many processes of various kinds of cancer cells. Our previous studies also demonstrated that AQP5 was highly expressed in epithelial ovarian cancer and contributed to the progress of ovarian cancer.

Methods

Lentivirus for knocking-down the expression of AQP5 was prepared and verified by qPCR and Western blotting. Cell counting kit-8 (CCK8) assay and transwell assay were performed to investigate the role of AQP5 on proliferation and migration of 3AO cells. The effects of down-regulating AQP5 on tumorigenesis were tested by tumor xenografts experiments.

Results

An effective lentivirus silencing AQP5 expression was obtained and used in this study. Down-regulating AQP5 inhibited proliferation and migration of cultured human epithelial ovarian cancer 3AO Cell. Furthermore, interfering of AQP5 during tumorigenesis could efficiently decrease the tumor growth in athymic mice.

Conclusions

These findings altogether suggest that AQP5 regulated multi processes in ovarian carcinogenesis and may be an attractive therapeutic target.

Human aquaporins: regulators of transcellular water flow

BACKGROUND

Emerging evidence supports the view that (AQP) aquaporin water channels are regulators of transcellular water flow. Consistent with their expression in most tissues, AQPs are associated with diverse physiological and pathophysiological processes.

SCOPE OF REVIEW

AQP knockout studies suggest that the regulatory role of AQPs, rather than their action as passive channels, is their critical function. Transport through all AQPs occurs by a common passive mechanism, but their regulation and cellular distribution varies significantly depending on cell and tissue type; the role of AQPs in cell volume regulation (CVR) is particularly notable. This review examines the regulatory role of AQPs in transcellular water flow, especially in CVR. We focus on key systems of the human body, encompassing processes as diverse as urine concentration in the kidney to clearance of brain oedema.

MAJOR CONCLUSIONS

AQPs are crucial for the regulation of water homeostasis, providing selective pores for the rapid movement of water across diverse cell membranes and playing regulatory roles in CVR. Gating mechanisms have been proposed for human AQPs, but have only been reported for plant and microbial AQPs. Consequently, it is likely that the distribution and abundance of AQPs in a particular membrane is the determinant of membrane water permeability and a regulator of transcellular water flow.

GENERAL SIGNIFICANCE

Elucidating the mechanisms that regulate transcellular water flow will improve our understanding of the human body in health and disease. The central role of specific AQPs in regulating water homeostasis will provide routes to a range of novel therapies. This article is part of a Special Issue entitled Aquaporins.