High Glucose Induces VEGF-C Expression via the LPA1/3-Akt-ROS-LEDGF Signaling Axis in Human Prostate Cancer PC-3 Cells

Cell Physiol Biochem. 2018;50(2):597-611. doi: 10.1159/000494177. Epub 2018 Oct 12.

Abstract

Background/aims: Hyperglycemia has been shown to increase the incidence and metastasis in various types of cancers. However, the correlation between hyperglycemia and lymphatic metastasis in prostate cancer (PCa) remains unclear. Our previous study demonstrated that lysophosphatidic acid (LPA) enhances vascular endothelial growth factor-C (VEGF-C) expression, a lymphangiogenic factor, through activating it receptors LPA1/3 in prostate cancer (PCa) cells. Moreover, hyperglycemia up-regulates autotaxin (ATX) expression, a LPA-generating enzyme. Therefore, we propose that high glucose promotes VEGF-C expression through LPA signaling in PCa cells.

Methods: Pharmacological inhibitors and siRNAs were utilized to investigate the molecular mechanism of high glucose-induced VEGF-C expression. Real-time PCR and Western blot were used to determine the mRNA and protein expressions, respectively. Cellular bioenergetics analysis was performed to determine the glycolysis levels.

Results: We demonstrated that the expressions of VEGF-C, ATX, and calreticulin were increased upon high glucose treatments in PC-3 cells. Moreover, high glucose-induced VEGF-C expression was mediated through the LPA1/3, PLC, Akt, ROS and LEDGF-dependent pathways. Additionally, high glucose enhanced the aerobic glycolysis via LPA1/3.

Conclusion: These results indicated that hyperglycemia leads to LPA synthesis, and subsequent promoting pathological consequence of PCa. These novel findings could potentially provide new strategies for PCa treatments.

Keywords: Hyperglycemia; Lymphangiogenesis; Lysophosphatidic acid; Prostate cancer; Vascular endothelial growth factor-C.

MeSH terms

  • Calreticulin / antagonists & inhibitors
  • Calreticulin / genetics
  • Calreticulin / metabolism
  • Cell Line, Tumor
  • Glucose / pharmacology*
  • Glycolysis
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Lysophospholipids / metabolism
  • Male
  • Oxygen Consumption / drug effects
  • Phosphoinositide Phospholipase C / genetics
  • Phosphoinositide Phospholipase C / metabolism
  • Phosphoric Diester Hydrolases / genetics
  • Phosphoric Diester Hydrolases / metabolism
  • Prostatic Neoplasms / pathology
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Reactive Oxygen Species / metabolism
  • Receptors, Lysophosphatidic Acid / antagonists & inhibitors
  • Receptors, Lysophosphatidic Acid / genetics
  • Receptors, Lysophosphatidic Acid / metabolism
  • Signal Transduction / drug effects*
  • Up-Regulation / drug effects
  • Vascular Endothelial Growth Factor C / genetics
  • Vascular Endothelial Growth Factor C / metabolism*

Substances

  • Calreticulin
  • Intercellular Signaling Peptides and Proteins
  • Lysophospholipids
  • RNA, Small Interfering
  • Reactive Oxygen Species
  • Receptors, Lysophosphatidic Acid
  • Vascular Endothelial Growth Factor C
  • lens epithelium-derived growth factor
  • Proto-Oncogene Proteins c-akt
  • Phosphoric Diester Hydrolases
  • Phosphoinositide Phospholipase C
  • alkylglycerophosphoethanolamine phosphodiesterase
  • Glucose
  • lysophosphatidic acid