Medicine and Health Sciences Commons^™

Pipkiγ Regulates Focal Adhesion Dynamics And Colon Cancer Cell Invasion, Zhaofei Wu, Xiang Li, Manjula Sunkara, Heather Spearman, Andrew J. Morris, Cai Huang

Markey Cancer Center Faculty Publications

Focal adhesion assembly and disassembly are essential for cell migration and cancer invasion, but the detailed molecular mechanisms regulating these processes remain to be elucidated. Phosphatidylinositol phosphate kinase type Iγ (PIPKIγ) binds talin and is required for focal adhesion formation in EGF-stimulated cells, but its role in regulating focal adhesion dynamics and cancer invasion is poorly understood. We show here that overexpression of PIPKIγ promoted focal adhesion formation, whereas cells expressing either PIPKIγ^K188,200R or PIPKIγ^D316K, two kinase-dead mutants, had much fewer focal adhesions than those expressing WT PIPKIγ in CHO-K1 cells and HCT116 colon cancer cells. Furthermore, …

Critical Role Of Pi3k/Akt/Gsk3Β In Motoneuron Specification From Human Neural Stem Cells In Response To Fgf2 And Egf, Luis Ojeda, Junling Gao, Kristopher G. Hooten, Enyin Wang, Jason R. Thonhoff, Tiffany J. Dunn, Tianyan Gao, Ping Wu

Markey Cancer Center Faculty Publications

Fibroblast growth factor (FGF) and epidermal growth factor (EGF) are critical for the development of the nervous system. We previously discovered that FGF2 and EGF had opposite effects on motor neuron differentiation from human fetal neural stem cells (hNSCs), but the underlying mechanisms remain unclear. Here, we show that FGF2 and EGF differentially affect the temporal patterns of Akt and glycogen synthase kinase 3 beta (GSK3β) activation. High levels of phosphatidylinositol 3-kinase (PI3K)/Akt activation accompanied with GSK3β inactivation result in reduction of the motor neuron transcription factor HB9. Inhibition of PI3K/Akt by chemical inhibitors or RNA interference or overexpression of …

Sonic Hedgehog Dependent Phosphorylation By Ck1Α And Grk2 Is Required For Ciliary Accumulation And Activation Of Smoothened, Yongbin Chen, Noriaki Sasai, Guoqiang Ma, Tao Yue, Jianhang Jia, James Briscoe, Jin Jiang

Markey Cancer Center Faculty Publications

Hedgehog (Hh) signaling regulates embryonic development and adult tissue homeostasis through the GPCR-like protein Smoothened (Smo), but how vertebrate Smo is activated remains poorly understood. In Drosophila, Hh dependent phosphorylation activates Smo. Whether this is also the case in vertebrates is unclear, owing to the marked sequence divergence between vertebrate and Drosophila Smo (dSmo) and the involvement of primary cilia in vertebrate Hh signaling. Here we demonstrate that mammalian Smo (mSmo) is activated through multi-site phosphorylation of its carboxyl-terminal tail by CK1α and GRK2. Phosphorylation of mSmo induces its active conformation and simultaneously promotes its ciliary accumulation. We demonstrate that …

Possible Role Of Death Receptor-Mediated Apoptosis By The E3 Ubiquitin Ligases Siah2 And Posh, Perry A. Christian, Michael V. Fiandalo, Steven R. Schwarze

Markey Cancer Center Faculty Publications

BACKGROUND: A functioning ubiquitin proteasome system (UPS) is essential for a number of diverse cellular processes and maintenance of overall cellular homeostasis. The ability of proteasome inhibitors, such as Velcade, to promote extrinsic apoptotic effects illustrates the importance of the ubiquitin proteasome system in the regulation of death receptor signaling. Here, we set out to define the UPS machinery, particularly the E3 ubiquitin ligases, that repress apoptosis through the extrinsic pathway. A cell-based genome-wide E3 ligase siRNA screen was established to monitor caspase-8 activity following the addition of TRAIL.

RESULTS: Data from the high-throughput screen revealed that targeting the RING-finger …

Racial/Ethnic Disparities In Survival Among Men Diagnosed With Prostate Cancer In Texas, Arica L. White, Ann L. Coker, Xianglin L. Du, Katherine S. Eggleston, Melanie Williams

CRVAW Faculty Journal Articles

BACKGROUND:

To the authors' knowledge, few studies to date have examined racial differences in prostate cancer survival while controlling for socioeconomic status (SES). No such studies have examined this association in Texas, a large state with significant ethnic and racial diversity. The objective of this analysis was to determine whether racial disparities in survival for men diagnosed with prostate cancer in Texas from 1995 through 2002 remained after adjusting for SES, rural residence, and stage of disease.

METHODS:

A cohort of 87,449 men who were diagnosed with prostate cancer was identified from the Texas Cancer Registry. The SES measure was …

Pediatric Ethics Guidelines For Hereditary Medullary Thyroid Cancer, M. Sara Rosenthal, Douglas S. Diekema

Internal Medicine Faculty Publications

Hereditary medullary thyroid cancer is an aggressive cancer for which there is no standard effective systemic therapy, but which can be prevented through genetic screening and prophylactic thyroidectomy. Although this cancer accounts for roughly 17% of all pediatric thyroid cancers, a significant percentage of affected families do not "accept" screening, while many gene carriers delay or refuse prophylactic thyroid surgery for their children. Current genetic screening practices in medullary thyroid cancer are inadequate; more than 50% of index patients with hereditary medullary thyroid cancer present with a thyroid mass; up to 75% have distant metastasis. These proposed pediatric ethics guidelines …