ABT199/Venetoclax Synergism With Thiotepa in Acute Myeloid Leukemia (AML) Cells

“[...] the combination of ABT199/venetoclax and Thio enhances the cytotoxicity of (Flu+Clad+Bu) in AML cell lines and leukemia patient-derived cell samples.”

BUFFALO, NY- March 25, 2024 – A new research paper was published in Oncotarget's Volume 15 on March 14, 2024, entitled, “ABT199/venetoclax synergism with thiotepa enhances the cytotoxicity of fludarabine, cladribine and busulfan in AML cells.”

ABT199/venetoclax, an inhibitor of the pro-survival BCL-2 protein, has improved AML treatment. Its efficacy in hematopoietic stem cell transplantation (HSCT), when combined with other chemotherapeutic drugs, has not been thoroughly investigated. In this new study, researchers Benigno C. Valdez, Bin Yuan, David Murray, Jeremy L. Ramdial, Uday Popat, Yago Nieto, and Borje S. Andersson from The University of Texas MD Anderson Cancer Center and the University of Alberta demonstrate the synergistic cytotoxicity of ABT199/venetoclax with the DNA alkylator thiotepa (Thio) in AML cells. 

“The results may provide relevant information for the design of clinical trials using these drugs to circumvent recognized drug-resistance mechanisms when used as part of pre-transplant conditioning regimens for AML patients undergoing allogenic HSCT.”

Cleavage of Caspase 3, PARP1 and HSP90, as well as increased Annexin V positivity, suggest potent activation of apoptosis by this two-drug combination; increased levels of γ-H2AX, P-CHK1 (S317), P-CHK2 (S19) and P-SMC1 (S957) indicate an enhanced DNA damage response. Likewise, the increased level of P-SAPK/JNK (T183/Y185) and decreased P-PI3Kp85 (Y458) suggest enhanced activation of stress signaling pathways. These molecular readouts were synergistically enhanced when ABT199/venetoclax and Thio were combined with fludarabine, cladribine and busulfan. 

The five-drug combination decreased the levels of BCL-2, BCL-xL and MCL-1, suggesting its potential clinical relevance in overcoming ABT199/venetoclax resistance. Moreover, this combination is active against P53-negative and FLT3-ITD-positive cell lines. Enhanced activation of apoptosis was observed in leukemia patient-derived cell samples exposed to the five-drug combination, suggesting a clinical relevance. 

“The results provide a rationale for clinical trials using these two- and five-drug combinations as part of a conditioning regimen for AML patients undergoing HSCT.”

Continue reading: DOI: https://doi.org/10.18632/oncotarget.28563 

Correspondence to: Benigno C. Valdez

Email: mbalasik@yahoo.com 

Keywords: acute myeloid leukemia, pre-transplant regimens, venetoclax, thiotepa, busulfan

Click here to sign up for free Altmetric alerts about this article.

About Oncotarget: Oncotarget (a primarily oncology-focused, peer-reviewed, open-access journal) aims to maximize research impact through insightful peer-review; eliminate borders between specialties by linking different fields of oncology, cancer research and biomedical sciences; and foster application of basic and clinical science.

Oncotarget is indexed and archived by PubMed/Medline, PubMed Central, Scopus, EMBASE, META (Chan Zuckerberg Initiative) (2018-2022), and Dimensions (Digital Science).

To learn more about Oncotarget, visit Oncotarget.com and connect with us on social media:

X, formerly Twitter
Facebook
YouTube
Instagram
LinkedIn
Pinterest
Spotify, and available wherever you listen to podcasts

Click here to subscribe to Oncotarget publication updates.

For media inquiries, please contact media@impactjournals.com.

Oncotarget Journal Office

6666 East Quaker Str., Suite 1A

Orchard Park, NY 14127

Phone: 1-800-922-0957 (option 2)