Fig. 6

ACYP2 promotes malignant phenotypes of glioma cells through interacting with PMCA4. a, Western blot analysis was performed in glioma cells to confirm PMCA4 knockdown by two different siRNAs (si-PMCA4–1023 and − 2728). GAPDH was used as a loading control. b, PMCA4 knockdown significantly inhibited glioma cell proliferation in comparison with the control. c, Co-IP was carried out in glioma cells to determine the interaction between ACYP2 and PMCA4 using antibodies against ACYP2 (upper panel) and PMCA4 (lower panel). Cells ectopically expressing ACYP2 and control cells were transfected with siRNA targeting PMCA4 or not. d, MTT assay was carried out to evaluate their effect on cell proliferation. e, Western blot analysis was used to investigate their effect on the activities of c-Myc and STAT3. Tubulin was used as a loading control. f, A schematic model of ACYP2 promoting malignant progression of glioma. Briefly, increased expression of ACYP2 interacts with and activates PMCA4, increasing the efficiency of the transport and promoting Ca²⁺ efflux. Lower free intracellular Ca²⁺ can decrease calpain activity, reducing the cleavage of c-Myc and PTP1B and subsequently enhancing transcriptional activities of c-Myc and STAT3. This will ultimately contribute to malignant phenotypes of glioma cells