Real-Time Monitoring of Cancer Cells Under Hypoxic Conditions Reveals Novel Regulator of Proliferation and Migration

Vivian Cao News

Employing an xCELLigence Real-Time Cell Analysis instrument, Korean scientists demonstrate that within a hypoxic environment the hYSK1 protein negatively regulates p16 to promote tumorigenesis

Tracking the growth and migration of cells under hypoxic conditions in vitro can be challenging because measurements must be made in a manner that does not perturb the atmospheric composition of the closed system.  A team of Korean scientists headed by Bu Young Choi at Seowon University have described an elegant solution to this challenge by placing an xCELLigence Real-Time Cell Analyzer (RTCA) directly within a hypoxia chamber.  This approach, wherein the number, size, attachment strength, and migration of cells are continuously monitored using gold biosensors, enabled experiments to be run from start to finish without ever needing to manipulate samples or open the hypoxia chamber.

Owing to their rapid proliferation, the cells within a solid tumor often outpace the ability of the surrounding vasculature to provide nutrients and oxygen.  This hypoxic microenvironment has distinct biochemical effects on tumor progression, but the underlying mechanisms are not completely understood.  Citing that levels of the cell cycle inhibitor/tumor suppressor protein p16 are reduced within hypoxic tumors, Choi’s team sought to provide a molecular explanation for this phenomenon.  Screening an extensive protein array for p16 binding proteins identified hYSK1, an oxidative stress response kinase.  After detailed biochemical mapping of the p16 and hYSK1 interaction domains the authors validated the physiological relevance of this interaction using a variety of in vivo assays.  hYSK1 was found to suppress p16 expression and to, under hypoxic conditions, directly bind p16 and thereby sequester it away from CDK4 binding.  Hypoxic stimulation of HYSK1 expression was also found to stimulate expression of matrix metalloproteinase 2, which is known to contribute to basement membrane degradation and metastatic spread.  Consistent with the above findings, in hypoxic xCELLigence live cell analysis assays hYSK1 promoted both proliferation and migration of melanoma cell lines.

Choi’s team concluded that “hYSK1 is a specific negative regulator of the tumor suppressor p16 and may represent a novel molecular target for reactivation of tumor suppressor genes in humans.”  To see their full manuscript, click here.

About xCELLigence® RTCA

xCELLigence® Real Time Cell Analysis (RTCA) instruments utilize gold biosensors embedded in the bottom of microtiter wells to non-invasively monitor the status of adherent cells using the principle of cellular impedance.  In short, cells act as insulators – impeding the flow of a miniscule electric current between electrodes.  This impedance signal is measured automatically, at an interval defined by the user, and provides an extremely sensitive readout of cell number, cell size, cell-substrate attachment strength, and cell invasion/migration.  xCELLigence® RTCA instruments are being used in both academia and industry for basic and applied applications ranging from cancer immunotherapy and cardiotoxicity to drug discovery and viral titer determination.  To date xCELLigence® has been used in more than 1,400 publications, which can be viewed in a searchable library.

About ACEA Biosciences

Founded in 2002, ACEA Biosciences is a pioneer in the development and commercialization of high performance, cutting edge cell analysis platforms for life science research.  ACEA’s xCELLigence® impedance-based, label-free, real-time cell analysis instruments and NovoCyte® flow cytometer are used in pre-clinical drug discovery and development, toxicology, safety pharmacology, and basic academic research.  More than 2,000 instruments have been placed globally.

For further information please contact:

ACEA Biosciences, Inc.
Dr. Jeff Xue
Phone: 1-858-724-0928, x3075
email: jxue(at)aceabio(dot)com