Publications by authors named "James J Hoy"
The PKA-inhibitor (PKI) family members PKIα, PKIβ, and PKIγ bind with high affinity to PKA and block its kinase activity, modulating the extent, and duration of PKA-mediated signaling events. While PKA is a well-known regulator of physiological and oncogenic events, the role of PKI proteins in these pathways has remained elusive. Here, by measuring activation of the MAPK pathway downstream of GPCR-Gαs-cAMP signaling, we show that the expression levels of PKI proteins can alter the balance of activation of two major cAMP targets: PKA and EPAC.
View Article and Find Full Text PDFAtypical chemokine receptors (ACKRs) are seven-transmembrane cell surface protein receptors expressed in immune cells, normal mesenchymal cells, and several tumor cells. As of this writing, six ACKRs have been characterized by diverse activities. They bind both cysteine-cysteine (CC) type and cysteine-X-cysteine (CXC)-type chemokines, either alone, or together with a ligand bound-functional G-protein coupled (typical) chemokine receptor.
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- β-Arrestins, specifically ARRB1 and ARRB2, play significant roles in bladder cancer by influencing tumor behavior and response to chemotherapy.
- The study found that ARRB2 is an important independent predictor of metastasis and chemotherapy outcomes, showing around 80% accuracy in predicting clinical results.
- Altering levels of ARRBs affects cancer stem cell characteristics, with increased ARRB2 levels leading to reduced tumor growth and enhanced sensitivity to Gemcitabine treatment.
The atypical C-X-C chemokine receptor 7 (CXCR7) has been implicated in supporting aggressive cancer phenotypes in several cancers including prostate cancer. However, the mechanisms driving overexpression of this receptor in cancer are poorly understood. This study investigates the role of androgen receptor (AR) in regulating CXCR7.
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- Prostate cancer (PCa) is the most common cancer in men, driven by hormones, and while advances in treatment have improved survival, over 20% of patients may develop aggressive forms that resist current therapies.
- Research into natural products from marine sponges, mushrooms, and edible plants is ongoing, as these compounds may target multiple mechanisms of cancer progression, unlike many synthetic drugs that often focus on a single target.
- Nutraceuticals that modulate androgen receptor signaling and other pathways show promise as potential treatments for hormone-refractory PCa, possibly serving as either standalone therapies or in conjunction with traditional treatments.
Unlabelled: The atypical 7-transmembrane chemokine receptor, CXCR7, transactivates the EGFR leading to increased tumor growth in several tumor types. However, the molecular mechanism of CXCR7 ligand-independent EGFR transactivation is unknown. We used cDNA knock-in, RNAi and analysis of mitogenic signaling components in both normal prostate epithelial cells and prostate cancer cells to decipher the proliferation-inducing mechanism of the CXCR7-EGFR interaction.
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