Project description:All-trans-retinoic acid (ATRA) has been successfully used in therapy of acute promyelocytic leukemia (APL), a cytogenetically distinct subtype of acute myeloid leukemia (AML) but the response of non-APL AML cases to ATRA-based treatment has been poor. Here we show that, via epigenetic reprogramming, inhibitors of LSD1/KDM1 demethylase including tranylcypromine (TCP) unlocked the ATRA-driven therapeutic response in non-APL AML. LSD1 inhibition did not lead to an increase in genome-wide H3 lysine4 dimethylation (H3K4me2) but did increase H3K4me2 and expression of myeloid differentiation-associated genes. Importantly, treatment with ATRA plus TCP dramatically diminished engraftment of primary human AML cells in vivo in NOD.SCID mice, suggesting that ATRA in combination with TCP may target leukemia-initiating cells. Furthermore, initiation of ATRA plus TCP co-treatment 15 days post-engraftment of human AML cells in NOD.SCID gamma mice also revealed the ATRA plus TCP drug combination to have a potent anti-leukemic effect, which was superior to treatment with either drug alone. These data identify LSD1 as a therapeutic target and strongly suggest that it may contribute to AML pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for novel combinatorial therapies of AML. ChIP-seq was used to study the effects of ATRA, TCP and ATRA/TCP treatment on H3K4 dimethylation. In addition to the three treatment samples, two reference samples were processed: (i) An untreated sample using the same anti-H3K4me2 antibody and an untreated sample using IgG. These five sequencing experiments were conducted using HL-60 cells and TEX cells, leading to 10 ChIP-seq samples in total.
Project description:All-trans-retinoic acid (ATRA) has been successfully used in therapy of acute promyelocytic leukemia (APL), a cytogenetically distinct subtype of acute myeloid leukemia (AML) but the response of non-APL AML cases to ATRA-based treatment has been poor. Here we show that, via epigenetic reprogramming, inhibitors of LSD1/KDM1 demethylase including tranylcypromine (TCP) unlocked the ATRA-driven therapeutic response in non-APL AML. LSD1 inhibition did not lead to an increase in genome-wide H3 lysine4 dimethylation (H3K4me2) but did increase H3K4me2 and expression of myeloid differentiation-associated genes. Importantly, treatment with ATRA plus TCP dramatically diminished engraftment of primary human AML cells in vivo in NOD.SCID mice, suggesting that ATRA in combination with TCP may target leukemia-initiating cells. Furthermore, initiation of ATRA plus TCP co-treatment 15 days post-engraftment of human AML cells in NOD.SCID gamma mice also revealed the ATRA plus TCP drug combination to have a potent anti-leukemic effect, which was superior to treatment with either drug alone. These data identify LSD1 as a therapeutic target and strongly suggest that it may contribute to AML pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for novel combinatorial therapies of AML.
Project description:ATRA is an active metabolite of vitamin A that is frequently used for the treatment of acute promyelocytic leukemia (APL) patients. Despite the success of this treatment, some APL patients are refractory or relapse. This emphasis the need for new therapeutic strategies aiming to improve the anti-cancer effect of ATRA. We and other have previously shown that autophagy is activated during ATRA-induced granulocytic differentiation of acute promyelocytic leukemia cells. Although the transcription effect of ATRA on autophagy has been well-documented, little is known on the post-transcription/ post-translational regulation autophagy in response to ATRA. Given the importance of calcium ions in the control of autophagy, we hypothesized that calcium ions are involved in the initiation of autophagy by ATRA in APL cells. We thus examined how ATRA regulate intracellular calcium and sense perturbation of Ca2+ responses to autophagy, differentiation and cell death in APL cells.
Project description:Total RNA from 4 sample which are control and differentiation stage after treated ATRA with 4days (Embryonic body, Embryonic body + ATRA (0D), Embryonic body + ATRA (6D), Embryonic body + ATRA (10D))
Project description:Arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) combination safely cures fatal acute promyelocytic leukemia, but the mechanisms underlying their action and synergy remain elusive. ATRA inhibits APL, breast and liver cancers by targeting isomerase Pin1, a master regulator of oncogenic signaling. Here we show that ATO targets Pin1 and cooperates with ATRA to exert potent anticancer activity. ATO inhibits and degrades Pin1, and suppresses its oncogenic function by noncovalent binding to Pin1’s active site. ATRA increases cellular ATO uptake through upregulating aquaporin-9. ATO and ATRA, at clinically safe doses, cooperatively ablate Pin1 to block numerous cancer-driving pathways and inhibit the growth of triple-negative breast cancer cells and tumor-initiating cells in cell and animal models including patient-derived orthotopic xenografts, similar to Pin1 CRISPR knockout, which is substantiated by comprehensive protein and microRNA analyses. Thus, synergistic Pin1 inhibition by ATO and ATRA offers an attractive approach to combating breast and other cancers.
Project description:Using H9C2 cardiomyoblasts, we have shown that all-trans retinoic acid (ATRA), the biologically active metabolite of vitamin A, affects mitochondrial dynamics at 10nM concentration. The low dose ATRA stimulates the expression of nuclear retinoid receptors and induces mechanisms that are protective against severe point damage caused by laser irradiation at the mitochondrial level. To determine the protective effect of ATRA against photodamage, we used the proteomic analysis based on liquid chromatography and mass spectrometry (LC-MS/MS) to compare the abundancies of proteins between control and ATRA-treated cardiomyoblasts.