Anti-PPFIA1 (aa 310-360) polyclonal Antibody

The role of the immune system in response to chemotherapeutic agents remains elusive. The interpatient variability observed in immune and chemotherapeutic cytotoxic responses is likely, at least in part, due to complex genetic differences. Through the use of a panel of genetically diverse mouse inbred strains, we developed a drug screening platform aimed at identifying genes underlying these chemotherapeutic cytotoxic effects on immune cells. Using genome-wide association studies (GWAS), we identified four genome-wide significant quantitative trait loci (QTL) that contributed to the sensitivity of doxorubicin and idarubicin in immune cells. Of particular interest, a locus on chromosome 16 was significantly associated with cell viability following idarubicin administration (p = 5.01 x 10-(8)). Within this QTL lies App, which encodes amyloid beta precursor protein. Comparison of dose-response curves verified that T-cells in App knockout mice were more sensitive to idarubicin than those of C57BL16J control mice (p < 0.05). In conclusion, the cellular screening approach coupled with GWAS led to the identification and subsequent validation of a gene involved in T-cell viability after idarubicin treatment. Previous studies have suggested a role for App in in vitro and in vivo cytotoxicity to anticancer agents; the overexpression of App enhances resistance, while the knockdown of this gene is deleterious to cell viability. Further investigations should include performing mechanistic studies, validating additional genes from the GWAS, including Ppfia1 and Ppfibp1, and ultimately translating the findings to in vivo and human studies.

Background: Acquired multidrug resistance is often blamed for the failure of chemotherapy in patients with malignant tumors, including chronic myeloid leukemia (CML). In this study, the authors investigated the role of circular RNA 0080145 (circ_0080145) in imatinib (IM) resistance of CML. Materials and Methods: Quantitative real-time polymerase chain reaction was applied to measure the expression of circ_0080145, microRNA-326 (miR-326), and PTPRF interacting protein alpha 1 (PPFIA1) mRNA. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to determine the half maximal inhibitory concentration (IC50) of IM and cell proliferation. Flow cytometry analysis was utilized to assess cell apoptosis. The levels of glucose uptake and lactate production were examined using specific kits. Protein levels were detected through western blot assay. The targeting relationship between miR-326 and circ_0080145 or PPFIA1 was verified by dual-luciferase reporter assay. The murine xenograft model was constructed to investigate the effect of circ_0080145 in vivo. Results: circ_0080145 was upregulated in IM-resistant CML patients and cells. circ_0080145 silencing suppressed IM resistance, cell growth, and glycolysis and induced apoptosis in IM-resistant CML cells in vitro. Moreover, circ_0080145 knockdown blocked tumor growth and IM resistance in vivo. miR-326 was a target of circ_0080145, and miR-326 inhibition restored the effects of circ_0080145 silencing on cell progression and IM resistance. In addition, PPFIA1 was a target gene of miR-326. The suppressive roles in IM resistance, cell growth and glycolysis, and the promotional role in apoptosis mediated by miR-326 were abolished by PPFIA1 overexpression in IM-resistant CML cells. Conclusion: circ_0080145 contributes to IM resistance via modulating miR-326/PPFIA1 axis, which might provide a novel avenue for CML therapy.