Go to The Journal of Clinical Investigation
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Journal stats
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact
  • Physician-Scientist Development
  • Current issue
  • Past issues
  • By specialty
    • COVID-19
    • Cardiology
    • Immunology
    • Metabolism
    • Nephrology
    • Oncology
    • Pulmonology
    • All ...
  • Videos
  • Collections
    • In-Press Preview
    • Resource and Technical Advances
    • Clinical Research and Public Health
    • Research Letters
    • Editorials
    • Perspectives
    • Physician-Scientist Development
    • Reviews
    • Top read articles

  • Current issue
  • Past issues
  • Specialties
  • In-Press Preview
  • Resource and Technical Advances
  • Clinical Research and Public Health
  • Research Letters
  • Editorials
  • Perspectives
  • Physician-Scientist Development
  • Reviews
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Journal stats
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact
Stabilization of the PP2A-B56α complex overcomes venetoclax-azacitidine resistance by impairing OXPHOS in AML
Silvia Romero-Murillo, Irene Peris, Anna Maria Lucianò, Nerea Marcotegui, Carmen Vicente, Brian Tran, Kelsey Barrie, Caitlin M. O’Connor, Andrea Torres-López, Maria C. Mateos, Maria L. Cayuela, Victoriano Mulero, Joaquín Fernández-Irigoyen, Enrique Santamaría, Maria D. Odero, Goutham Narla
Silvia Romero-Murillo, Irene Peris, Anna Maria Lucianò, Nerea Marcotegui, Carmen Vicente, Brian Tran, Kelsey Barrie, Caitlin M. O’Connor, Andrea Torres-López, Maria C. Mateos, Maria L. Cayuela, Victoriano Mulero, Joaquín Fernández-Irigoyen, Enrique Santamaría, Maria D. Odero, Goutham Narla
View: Text | PDF
Research Article Cell biology Hematology

Stabilization of the PP2A-B56α complex overcomes venetoclax-azacitidine resistance by impairing OXPHOS in AML

  • Text
  • PDF
Abstract

Cell metabolic rewiring is associated with resistance to venetoclax-azacitidine (Ven-Aza) combination therapy and relapse in patients with acute myeloid leukemia (AML). Drug-resistant cells exhibit an enhanced reliance on oxidative phosphorylation (OXPHOS) for energy production. Therefore, impairing mitochondrial metabolism represents an exciting strategy to face this unmet clinical need. We recently demonstrated that the specific activation of the phosphatase PP2A-B56α enhances the proapoptotic efficacy of venetoclax in AML. Here, through leveraging unbiased multi-omics–based approaches and using both genetic and pharmacological tools, we define key roles for the tumor suppressor PP2A-B56α complex in OXPHOS regulation and treatment response in disease-relevant AML models. From a translational perspective, the specific stabilization of PP2A-B56α heterocomplex with the potentially novel PP2A molecular glue activator, RPT04402, reduces OXPHOS levels in treatment-resistant AML cells and improves treatment response in both Ven-Aza–sensitive and –resistant AML cell lines, primary cells, and in vivo models. Together, our work supports further research on targeted combination therapy approaches based on PP2A-B56α stabilization to counteract OXPHOS-related treatment resistance and improve AML responses in a patient population with historically poor outcomes.

Authors

Silvia Romero-Murillo, Irene Peris, Anna Maria Lucianò, Nerea Marcotegui, Carmen Vicente, Brian Tran, Kelsey Barrie, Caitlin M. O’Connor, Andrea Torres-López, Maria C. Mateos, Maria L. Cayuela, Victoriano Mulero, Joaquín Fernández-Irigoyen, Enrique Santamaría, Maria D. Odero, Goutham Narla

×

Figure 6

RPT04402 improves the response to venetoclax-azacitidine therapy in resistant models in vivo.

Options: View larger image (or click on image) Download as PowerPoint
RPT04402 improves the response to venetoclax-azacitidine therapy in resi...
(A) Schematic representation of zebrafish xenotransplantation and treatment workflow. Drug doses: 500 nM Ven, 1 μM Aza, and/or 20 μM RPT04402. (B and C) Representative images of HL-60-R and OCI-AML3-R (B) as well as HL-60 and OCI-AML3 cell lines (C) in xenograft larvae tail at 72 hours postinjection (hpi). AML cells were tracked as green-emitting fluorescent cells. (D and E) Cell invasion capacity of parental and Ven-Aza resistant cell lines were measured as the number of cells present in the caudal hematopoietic tissue after 70 hours of treatment. Each point represents one zebrafish larvae. Statistical significance was determined by 1-way ANOVA and Tukey post hoc test in HL-60 and HL-60-R cells, and by Kruskal-Wallis and Dunn post hoc test analyses for OCI-AML3 and OCI-AML3-R cell lines. (F) Schematic representation of in vivo subcutaneous efficacy study (detailed explanation in methods section). (G) Time-dependent tumor growth upon treatment of injected NSG mice with HL-60-R and OCI-AML3-R cell lines (n = ~15 mice per group). TGI, tumor growth inhibition. Statistical significance was determined by 2-way ANOVA and Tukey post hoc test. Data represent mean ± SEM. (H) Percentages of body weight change of NSG mice injected with HL-60-R and OCI-AML3-R cell lines after 15 and 22 days of treatment, respectively. Statistical significance was determined by 1-way ANOVA and Tukey post hoc test. Treatment doses: 10, 100, and 3 mg/kg for RPT04402, venetoclax, and azacitidine, respectively. (I) Cell invasion capacity of AML-3-R cells (72-hour treatment). Statistical significance was determined by Kruskal-Wallis and Dunn post hoc test analyses. On the right, representative images of AML-3-R cells of zebrafish PDX tail at 72 hours post-injection. Scale bar: 0.25 mm.

Copyright © 2026 American Society for Clinical Investigation
ISSN 2379-3708

Sign up for email alerts