Date of Award
Summer 8-10-2010
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Biology
First Advisor
Dr. Zhi-Ren Liu
Second Advisor
Dr. E. Shyam P. Reddy
Third Advisor
Dr. Shi-Yong Sun
Fourth Advisor
Dr. Susanna Greer
Abstract
Cancer cells take more glucose to provide energy and phosphoryl intermediates for cancer progression. Meanwhile, energy-provider function of mitochondria in cancer cells is disrupted. This phenomenon is so-called Warburg effect, which is discovered over eighty years ago. The detail mechanisms for Warburg effect are not well defined. How glycolytic enzymes contribute to cancer progression is not well known. PKM2 is a glycolytic enzyme dominantly localized in the cytosol, catalyzing the production of ATP from PEP. In this study, we discovered that there were more nuclear PKM2 expressed in highly proliferative cancer cells. The nuclear PKM2 levels are correlated with cell proliferation rates. According to our microarry analyses, MEK5 gene was upregulated in PKM2 overexpression cells. Our studies showed that PKM2 regulated MEK5 gene transcription to promote cell proliferation. Moreover, nuclear PKM2 phosphorylated Stat3 at Y705 site using PEP as a phosphoryl group donor to regulate MEK5 gene transcription. Our study also showed that double phosphorylated p68 RNA helicase at Y593/595 interacted with PKM2 at its FBP binding site. Under the stimulation of growth factors, p68 interacted with PKM2 to promote the conversion from tetrameraic to dimeric form so as to regulate its protein kinase activity. Overexpression PKM2 in less aggressive cancer cells induced the formation of multinuclei by regulating Cdc14A gene transcription. Overall, this study presents a step forward in understanding the Warburg effect.
DOI
https://doi.org/10.57709/1371563
Recommended Citation
Gao, Xueliang, "Nuclear Pyruvate Kinase M2 Functional Study in Cancer Cells." Dissertation, Georgia State University, 2010.
doi: https://doi.org/10.57709/1371563