1. CXCR1 Expression in MDA-PCa-2b Cell Upregulates ITM2A to Inhibit Tumor Growth.
- Author
-
Adekoya, Timothy O., Smith, Nikia, Kothari, Parag, Dacanay, Monique A., Li, Yahui, and Richardson, Ricardo M.
- Abstract
Simple Summary: Prostate cancer constitutes a large percentage of cancer-related deaths among men. Due to the complexity of the disease process and resistance to androgen deprivation therapy, a lot remains unknown about prostate tumorigenesis. Recently, several chemokines, including CXCL8 and its receptors (CXCR1 and CXCR2), have been shown to impact the development and progression of prostate cancer. In this study, we used various assays and animal models to better understand the role of CXCL8 receptors in prostate cancer incidence. The results herein indicate that the receptors may have opposing effects in the onset of prostate cancer. CXCR1 expression, not CXCR2, upregulates the tumor suppressor ITM2A to inhibit prostate tumor growth. Background: Chemokines, along with their receptors, exert critical roles in tumor development and progression. In prostate cancer (PCa), interleukin-8 (IL-8/CXCL8) was shown to enhance angiogenesis, proliferation, and metastasis. CXCL8 activates two receptors, CXCR1 and CXCR2. While CXCR2 expression was shown to promote PCa growth and metastasis, the role of CXCR1 remains unclear. Methods: In this study, we stably expressed CXCR1 and, as control, CXCR2 in the androgen-dependent PCa cell line MDA-PCa-2b to evaluate the effect of CXCR1 in tumor development. Results: MDA-PCa-2b-CXCR1 cells showed decreased cell migration, protein kinase-B (AKT) activation, prostate-specific antigen (PSA) expression, cell proliferation, and tumor development in nude mice, relative to MDA-PCa-2b-Vec and MDA-PCa-2b-CXCR2 cells. MDA-PCa-2b-CXCR1 cells also displayed a significant transition to mesenchymal phenotypes as characterized by decreased E-cadherin expression and a corresponding increased level of N-cadherin and vimentin expression. RNA-seq and Western blot analysis revealed a significant increase in the tumor suppressor integral membrane protein 2A (ITM2A) expression in MDA-PCa-2b-CXCR1 compared to control cells. In prostate adenocarcinoma tissue, ITM2A expression was also shown to be downregulated relative to a normal prostate. Interestingly, the overexpression of ITM2A in MDA-PCa-2b cells (MDA-PCa-2b-ITM2A-GFP) inhibited tumor growth similar to that of MDA-PCa-2b-CXCR1. Conclusions: Taken together, the data suggest that CXCR1 expression in MDA-PCa-2b cells may upregulate ITM2A to abrogate tumor development. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF