How Glycosylphosphatidylinositol-phospholipase D acts in homing of hematopoietic stem/progenitor cells?

The p53/ZEB1-PLD3 feedback loop regulates cell proliferation in breast cancer

Breast cancer is the most prevalent cancer globally, endangering women's physical and mental health. Phospholipase D3 (PLD3) belongs to the phosphodiesterase family (PLD). PLD3 is related to insulin-mediated phosphorylation of the AKT pathway, suggesting that it may play a role in the occurrence and development of malignant tumors. This study may further explore the molecular mechanism of PLD3 inhibiting breast cancer cell proliferation. In this study, we demonstrated that PLD3 and miR-6796 are co-expressed in breast cancer. PLD3 can bind with CDK1 and inhibit its expression, leading to mitotic arrest and inhibiting breast cancer proliferation. Wild-type p53 regulates PLD3 and miR-6796 expression by competitively binding to the PLD3 promoter with ZEB1. DNMT3B, as the target gene of miR-6796, is recruited into the PLD3 promoter by combining with ZEB1 to regulate the DNA methylation of the PLD3 promoter and ultimately affect PLD3 and miR-6796 expression. In conclusion, we revealed the role and molecular mechanism of PLD3 and its embedded miR-6796 in breast cancer proliferation, providing clues and a theoretical foundation for future research and development of therapeutic targets and prognostic markers for breast cancer.

Glycosylphosphatidylinositol-specific phospholipase D improves glucose tolerance

Insulin regulation of energy metabolism is complex and involves numerous signaling cascades. Insulin has been suggested to stimulate a phospholipase that cleaves glycosylphosphatidylinositols resulting in the generation of an inositol glycan that serves as an insulin mediator. To determine if glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) may play a role in glucose metabolism, we examined the effect of overexpressing GPI-PLD using adenovirus-mediated gene transfer in C57BL/6 mice. Overexpressing GPI-PLD was associated with a decrease in fasting glucose as well as an improvement in glucose tolerance as determined by an intraperitoneal glucose tolerance test. This effect to improve glucose tolerance does not result from an increase in insulin sensitivity, as overexpressing GPI-PLD does not alter the response to insulin. In contrast, the insulin response during the glucose tolerance test in GPI-PLD-overexpressing mice was increased. Overexpressing GPI-PLD in an insulinoma cell line enhanced glucose-stimulated insulin secretion, suggesting that enhanced insulin secretion in vivo may have contributed to the improved glucose tolerance.