Arsenic trioxide induces apoptosis in NB-4, an acute promyelocytic leukemia cell line, through up-regulation of p73 via suppression of nuclear factor kappa B-mediated inhibition of p73 transcription and prevention of NF-κB-mediated induction of XIAP, cIAP2, BCL-XL and survivin

Abstract

The purpose of the present study is to evaluate the effects of arsenic trioxide (ATO) on human acute promyelocytic leukemia NB-4 cells. Microculture tetrazolium test, bromodeoxyuridine (BrdU) cell proliferation assay, caspase 3 activity assay, cell-based nuclear factor kappa B (NF-kappaB) phosphorylation measurement by ELISA and real-time RT-PCR were employed to appraise the effects of ATO on metabolic activity, DNA synthesis, induction of programmed cell death and NF-kappaB activation. The suppressive effects of ATO on metabolic potential, cell proliferation and NF-kappaB activation were associated with induction of apoptosis in NB-4 cells. In addition, an expressive enhancement in mRNA levels of p73, cyclin-dependent kinase inhibitor 1A (p21), tumor protein 53-induced nuclear protein 1 (TP53INP1), WNK lysine deficient protein kinase 2 (WNK2) and lipocalin 2 coupled with a significant reduction in transcriptional levels of NF-kappaB inhibitor beta (IKK2), Nemo, BCL2-like 1 (BCL-X(L)), inhibitor of apoptosis protein 1 (cIAP2), X-linked inhibitor of apoptosis protein (XIAP), survivin, Bcl-2, TIP60, ataxia telangiectasia (ATM), SHP-2 and sirtuin (SIRT1) were observed. Altogether, these issues show for the first time that ATO treatment could trammel cell growth and proliferation as well as induces apoptosis in NB-4 cells through induction of transcriptional levels of p73, TP53INP1, WNK2, lipocalin 2 as well as suppression of NF-kappaB-mediated induction of BCL-X(L), cIAP2, XIAP and survivin. Furthermore, the inductionary effects of ATO on transcriptional stimulation of p73 might be through cramping the NF-kappaB module (through suppression of p65 phosphorylation as well as transcriptional hindering of IKK2, ATM and Nemo) along with diminishing the mRNA expression of TIP60, SHP-2 and SIRT1.

A balancing act: orchestrating amino-truncated and full-length p73 variants as decisive factors in cancer progression

“…C35 and ΔNp73 colocalize at peri-nuclear region, suggesting a transcriptional-independent mechanism of NFκB and AKT activation. EGCG (epigallocatechin-3-gallate ) Upregulation of TAp73 expression [187][188][189] Red wine polyphenol Upregulation of TAp73 expression 190 Arsenic trioxide Upregulation of TAp73 expression 191,192 T-oligo Oligonucleotides homologous to the 3′-telomere overhang; upregulation of TAp73 expression 167,193,194 Propranolol Nonselective β-adrenergic receptor antagonist; upregulation of TAp73 expression 195 Melphalan Upregulation of TAp73 expression 196 Sodium butyrate Histone deacetylase inhibitor; upregulation of TAp73 expression 197 7-hydroxy-staurosporine Upregulation of TAp73 expression 197 Hydroxyurea DNA replication inhibitor; upregulation of TAp73 expression 198 Aphidicolin DNA polymerase α inhibitor; upregulation of TAp73 expression 198 Resveratrol DNA replication inhibitor; upregulation of TAp73 expression 198 4-propoxyphenol DNA replication inhibitor; upregulation of TAp73 expression 198 Celecoxib COX-2 inhibitor; upregulation of TAp73 and reduction of DNp73 expression 9,199 Tazarotene Upregulation of TAp73 and reduction of DNp73 expression 200 Interferon (IFN)α Reduction of DNp73 expression 201 …”

Alteration in miRNA gene expression pattern in acute promyelocytic leukemia cell induced by arsenic trioxide: a possible mechanism to explain arsenic multi-target action

“…Cell cytotoxicity was determined using MTT assay, as previously reported [20]. Briefly, the cells (5,000/well) were plated in 96-well plates and incubated at 37°C; the metabolic activity was assessed after 48 h by an uptake of thiazolyl blue tetrazolium bromide (Sigma) by viable cells at 490 nm.…”

“…After exposed to substrate tetramethyl-benzidine, the samples were read at 450 nm in an ELISA reader. The inhibitory rate of ATO on the proliferation of NB4 cells was calculated as previously described [20].…”

“…In harmony, we conducted both dose-response and timeresponse studies to appraise the effects of ATO on the NB4 cell growth inhibition, cytotoxicity, DNA synthesis, induction of programmed cell death, and caspase-3 activation. NB4 cells were treated with ATO at 0.5, 1, and 2 μM for 24 and 48 h. Since the pharmacological concentration of ATO 2 μM for 48 h was previously shown to induces apoptosis in NB4 [20], these concentration and time point were selected for determining the effect of ATO on the global expression levels of miRNAs in NB4 cells.…”

Up-Regulation of Glioma-Associated Oncogene Homolog 1 Expression by Serum Starvation Promotes Cell Survival in ER-Positive Breast Cancer Cells

“…Activation of the transcription factor NF-κB is a key pro-survival mechanism in cancer cells [36] and studies have shown that cIAP2 is a target gene of NF-κB [37,38]. Therefore, we examined whether NF-κB activation is involved in the pro-survival effect of Gli1 as well as up-regulation of cIAP2 expression.…”