RhoA and Rac1 play independent roles in lysophosphatidic acid-induced ovarian cancer chemotaxis.
Lysophosphatidic acid (LPA), which is a bioactive phospholipid existing at high level in ascites and plasma of ovarian cancer patients, is known to be involved in cell survival, proliferation, adhesion, and migration. Small guanosine triphosphatases (GTPases) such as RhoA and Rac1 are intracellular signaling molecules which affect morphology and chemotactic behavior of cells. In this research, we first investigated roles of RhoA and Rac1 in the LPA-induced chemotaxis of SKOV3 human ovarian cancer cells using a multilevel microfluidic platform. The multilevel microfluidic device was fabricated by a rapid prototyping method based on soft lithography using multi-layered adhesive tapes. This platform allows us to conduct the on-chip chemotaxis assays in conventional biology laboratories without any huge and expensive equipment for fabrication and fluidic manipulation. Based on image-based analysis of single cell trajectories in the microfluidic device, the chemotaxis of SKOV3 cells could be quantitatively analyzed in two independent parameters-migration speed and directional persistence. Inhibition of the RhoA/ROCK pathways reduced the directional persistence, not the migration speed, of the cells, while only the migration speed was decreased when the activity of Rac1/PAK pathways was suppressed. These results suggest that RhoA and Rac1 signaling pathways potentially play independent roles in the chemotactic migration of SKOV3 ovarian cancer cells in the linear and stable LPA concentration gradient. Our microfluidic platform would provide a rapid, low cost, easy-to-use, and versatile way for research of cancer cell migration which is crucial for tumor metastasis.
School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea. pgsuh@unist.ac.kr ykcho@unist.ac.kr.
Hyundoo
H
Hwang
Eung-Kyun
EK
Kim
Juhee
J
Park
Pann-Ghill
PG
Suh
Yoon-Kyoung
YK
Cho
D036002:ADP Ribose Transferases / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology; D000634:Aminoquinolines / Q000494:pharmacology; D001905:Botulinum Toxins / Q000494:pharmacology; D045744:Cell Line, Tumor; D002633:Chemotaxis / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology / Q000502:physiology; D046210:Microfluidic Analytical Techniques; D010051:Ovarian Neoplasms / Q000503:physiopathology*; D011725:Pyridines / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D020830:rac1 GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000502:physiology*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000502:physiology*
D000577:Amides; D000634:Aminoquinolines; D004791:Enzyme Inhibitors; D020662:Guanine Nucleotide Exchange Factors; D008246:Lysophospholipids; C487513:NSC 23766; D011725:Pyridines; D011743:Pyrimidines; C107953:RAC1 protein, human; C066737:RHOA protein, human; C108830:Y 27632; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D054460:rho-Associated Kinases; D001905:Botulinum Toxins; D020830:rac1 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein; C032881:lysophosphatidic acid