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Small molecule MIRA-1 induces in vitro and in vivo anti-myeloma activity and synergizes with current anti-myeloma agents.

Saha MN, Chen Y, Chen MH, Chen G, Chang H - Br. J. Cancer (2014)

Bottom Line: MIRA-1 treatment resulted in the inhibition of viability, colony formation, and migration and increase in apoptosis of MM cells irrespective of p53 status accompanied by upregulation of Puma and Bax and downregulation of Mcl-1 and c-Myc.Genetic knockdown of p53 did not abrogate apoptotic response of MIRA-1.Our data provide the preclinical framework for clinical evaluation of MIRA-1 as a novel therapeutic agent to improve patient outcome in MM.

View Article: PubMed Central - PubMed

Affiliation: 1] Division of Molecular and Cellular Biology, Toronto General Research Institute, Toronto, Ontario, Canada [2] Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Background: Small molecule MIRA-1 induced mutant p53-dependent apoptosis in several types of solid tumours. However, anti-tumour activity of MIRA-1 in haematological malignancies including multiple myeloma (MM) is unknown. In this study, we evaluated the effect of MIRA-1 in MM.

Methods: We examined the anti-tumour activity of MIRA-1 alone or in combination with current anti-myeloma agents in a panel of MM cell lines, primary MM samples, and in a mouse xenograft model of MM.

Results: MIRA-1 treatment resulted in the inhibition of viability, colony formation, and migration and increase in apoptosis of MM cells irrespective of p53 status accompanied by upregulation of Puma and Bax and downregulation of Mcl-1 and c-Myc. Genetic knockdown of p53 did not abrogate apoptotic response of MIRA-1. MIRA-1 triggered activation of PERK and IRE-α leading to splicing of XBP1 indicating an association of endoplasmic reticulum stress response. Furthermore, combined treatment of MIRA-1 with dexamethasone, doxorubicin or velcade displayed synergistic response in MM cells. Importantly, MIRA-1 alone or in combination with dexamethasone retarded tumour growth and prolonged survival without showing any untoward toxicity in the mice bearing MM tumour.

Conclusions: Our data provide the preclinical framework for clinical evaluation of MIRA-1 as a novel therapeutic agent to improve patient outcome in MM.

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Related in: MedlinePlus

MIRA-1 demonstrated potent anti-myeloma activity in vitro. (A) Chemical structures of MIRA-1; Chemical name: 1-[(1-Oxopropoxy)methyl]-1H-pyrrole-2,5-dione. Molecular formula: C8H9NO4 (B–E). (B) MM cell lines expressing wild-type p53 (MM.1S, H929) or mutant p53 (LP1, U266, and 8226) were incubated with MIRA-1 (0–20 μmol l−1), and viability was determined at 48 h using MTT assay. (C) MIRA-1-induced cytotoxicity in primary MM samples from newly diagnosed MM patients. Myeloma cells isolated from the bone marrow via CD138+ selection were cultured with MIRA-1 (0–20 μmol l−1), and viability was assessed by MTT at 48 h. (D) PBMCs and (E) BMMNCs were treated similarly with MIRA-1 and cyototoxicity was assessed by MTT assay. Viability of the cells was expressed as percentage of the DMSO-treated control. Data represents means (±s.d.) of triplicate cultures.
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fig1: MIRA-1 demonstrated potent anti-myeloma activity in vitro. (A) Chemical structures of MIRA-1; Chemical name: 1-[(1-Oxopropoxy)methyl]-1H-pyrrole-2,5-dione. Molecular formula: C8H9NO4 (B–E). (B) MM cell lines expressing wild-type p53 (MM.1S, H929) or mutant p53 (LP1, U266, and 8226) were incubated with MIRA-1 (0–20 μmol l−1), and viability was determined at 48 h using MTT assay. (C) MIRA-1-induced cytotoxicity in primary MM samples from newly diagnosed MM patients. Myeloma cells isolated from the bone marrow via CD138+ selection were cultured with MIRA-1 (0–20 μmol l−1), and viability was assessed by MTT at 48 h. (D) PBMCs and (E) BMMNCs were treated similarly with MIRA-1 and cyototoxicity was assessed by MTT assay. Viability of the cells was expressed as percentage of the DMSO-treated control. Data represents means (±s.d.) of triplicate cultures.

Mentions: Pharmacological screening of a diverse set of low molecular weight compounds led to the identification of a novel class of mutant p53 reactivating molecules, MIRA-1, a maleimide derivative (Figure 1A) (Bykov et al, 2005). MIRA-1 is structurally distinct from the previously described mutant p53-targeting compounds PRIMA-1, identified in the similar screening by the same groups. Studies using solid tumour cell models showed that MIRA-1 induces apoptosis via restoration of p53-dependent transcriptional transactivation. Importantly, MIRA-1 induces cell death with a potency that is even higher than that of PRIMA-1 (Bykov et al, 2005). To date, anti-tumour activity of MIRA-1 in haematological malignancies including MM is undefined. In the present study, we examined anti-myeloma activity of MIRA-1 using both in vitro and in vivo model systems. Our studies show that MIRA-1 is a potent small molecule which can kill MM cells harbouring wild-type or mutant p53.


Small molecule MIRA-1 induces in vitro and in vivo anti-myeloma activity and synergizes with current anti-myeloma agents.

Saha MN, Chen Y, Chen MH, Chen G, Chang H - Br. J. Cancer (2014)

MIRA-1 demonstrated potent anti-myeloma activity in vitro. (A) Chemical structures of MIRA-1; Chemical name: 1-[(1-Oxopropoxy)methyl]-1H-pyrrole-2,5-dione. Molecular formula: C8H9NO4 (B–E). (B) MM cell lines expressing wild-type p53 (MM.1S, H929) or mutant p53 (LP1, U266, and 8226) were incubated with MIRA-1 (0–20 μmol l−1), and viability was determined at 48 h using MTT assay. (C) MIRA-1-induced cytotoxicity in primary MM samples from newly diagnosed MM patients. Myeloma cells isolated from the bone marrow via CD138+ selection were cultured with MIRA-1 (0–20 μmol l−1), and viability was assessed by MTT at 48 h. (D) PBMCs and (E) BMMNCs were treated similarly with MIRA-1 and cyototoxicity was assessed by MTT assay. Viability of the cells was expressed as percentage of the DMSO-treated control. Data represents means (±s.d.) of triplicate cultures.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4007239&req=5

fig1: MIRA-1 demonstrated potent anti-myeloma activity in vitro. (A) Chemical structures of MIRA-1; Chemical name: 1-[(1-Oxopropoxy)methyl]-1H-pyrrole-2,5-dione. Molecular formula: C8H9NO4 (B–E). (B) MM cell lines expressing wild-type p53 (MM.1S, H929) or mutant p53 (LP1, U266, and 8226) were incubated with MIRA-1 (0–20 μmol l−1), and viability was determined at 48 h using MTT assay. (C) MIRA-1-induced cytotoxicity in primary MM samples from newly diagnosed MM patients. Myeloma cells isolated from the bone marrow via CD138+ selection were cultured with MIRA-1 (0–20 μmol l−1), and viability was assessed by MTT at 48 h. (D) PBMCs and (E) BMMNCs were treated similarly with MIRA-1 and cyototoxicity was assessed by MTT assay. Viability of the cells was expressed as percentage of the DMSO-treated control. Data represents means (±s.d.) of triplicate cultures.
Mentions: Pharmacological screening of a diverse set of low molecular weight compounds led to the identification of a novel class of mutant p53 reactivating molecules, MIRA-1, a maleimide derivative (Figure 1A) (Bykov et al, 2005). MIRA-1 is structurally distinct from the previously described mutant p53-targeting compounds PRIMA-1, identified in the similar screening by the same groups. Studies using solid tumour cell models showed that MIRA-1 induces apoptosis via restoration of p53-dependent transcriptional transactivation. Importantly, MIRA-1 induces cell death with a potency that is even higher than that of PRIMA-1 (Bykov et al, 2005). To date, anti-tumour activity of MIRA-1 in haematological malignancies including MM is undefined. In the present study, we examined anti-myeloma activity of MIRA-1 using both in vitro and in vivo model systems. Our studies show that MIRA-1 is a potent small molecule which can kill MM cells harbouring wild-type or mutant p53.

Bottom Line: MIRA-1 treatment resulted in the inhibition of viability, colony formation, and migration and increase in apoptosis of MM cells irrespective of p53 status accompanied by upregulation of Puma and Bax and downregulation of Mcl-1 and c-Myc.Genetic knockdown of p53 did not abrogate apoptotic response of MIRA-1.Our data provide the preclinical framework for clinical evaluation of MIRA-1 as a novel therapeutic agent to improve patient outcome in MM.

View Article: PubMed Central - PubMed

Affiliation: 1] Division of Molecular and Cellular Biology, Toronto General Research Institute, Toronto, Ontario, Canada [2] Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Background: Small molecule MIRA-1 induced mutant p53-dependent apoptosis in several types of solid tumours. However, anti-tumour activity of MIRA-1 in haematological malignancies including multiple myeloma (MM) is unknown. In this study, we evaluated the effect of MIRA-1 in MM.

Methods: We examined the anti-tumour activity of MIRA-1 alone or in combination with current anti-myeloma agents in a panel of MM cell lines, primary MM samples, and in a mouse xenograft model of MM.

Results: MIRA-1 treatment resulted in the inhibition of viability, colony formation, and migration and increase in apoptosis of MM cells irrespective of p53 status accompanied by upregulation of Puma and Bax and downregulation of Mcl-1 and c-Myc. Genetic knockdown of p53 did not abrogate apoptotic response of MIRA-1. MIRA-1 triggered activation of PERK and IRE-α leading to splicing of XBP1 indicating an association of endoplasmic reticulum stress response. Furthermore, combined treatment of MIRA-1 with dexamethasone, doxorubicin or velcade displayed synergistic response in MM cells. Importantly, MIRA-1 alone or in combination with dexamethasone retarded tumour growth and prolonged survival without showing any untoward toxicity in the mice bearing MM tumour.

Conclusions: Our data provide the preclinical framework for clinical evaluation of MIRA-1 as a novel therapeutic agent to improve patient outcome in MM.

Show MeSH
Related in: MedlinePlus