Dual Targeting of Apoptotic and Signaling Pathways in T-Lineage Acute Lymphoblastic Leukemia

Clin Cancer Res. 2023 Aug 15;29(16):3151-3161. doi: 10.1158/1078-0432.CCR-23-0415.

Abstract

Purpose: Relapsed T-acute lymphoblastic leukemia (T-ALL) has limited treatment options. We investigated mechanisms of resistance to BH3 mimetics in T-ALL to develop rational combination strategies. We also looked at the preclinical efficacy of NWP-0476, a novel BCL-2/BCL-xL inhibitor, as single agent and combination therapy in T-ALL.

Experimental design: We used BH3 profiling as a predictive tool for BH3 mimetic response in T-ALL. Using isogenic control, venetoclax-resistant (ven-R) and NWP-0476-resistant (NWP-R) cells, phosphokinase array was performed to identify differentially regulated signaling pathways.

Results: Typical T-ALL cells had increased dependence on BCL-xL, whereas early T-precursor (ETP)-ALL cells had higher BCL-2 dependence for survival. BCL-2/BCL-xL dual inhibitors were effective against both subtypes of T-lineage ALL. A 71-protein human phosphokinase array showed increased LCK activity in ven-R cells, and increased ACK1 activity in ven-R and NWP-R cells. We hypothesized that pre-TCR and ACK1 signaling pathways are drivers of resistance to BCL-2 and BCL-xL inhibition, respectively. First, we silenced LCK gene in T-ALL cell lines, which resulted in increased sensitivity to BCL-2 inhibition. Mechanistically, LCK activated NF-κB pathway and the expression of BCL-xL. Silencing ACK1 gene resulted in increased sensitivity to both BCL-2 and BCL-xL inhibitors. ACK1 signaling upregulated AKT pathway, which inhibited the pro-apoptotic function of BAD. In a T-ALL patient-derived xenograft model, combination of NWP-0476 and dasatinib demonstrated synergy without major organ toxicity.

Conclusions: LCK and ACK1 signaling pathways are critical regulators of BH3 mimetic resistance in T-ALL. Combination of BH3 mimetics with tyrosine kinase inhibitors might be effective against relapsed T-ALL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents* / pharmacology
  • Apoptosis
  • Cell Line, Tumor
  • Drug Resistance, Neoplasm / genetics
  • Humans
  • Myeloid Cell Leukemia Sequence 1 Protein / metabolism
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma* / drug therapy
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma* / genetics
  • Proto-Oncogene Proteins c-bcl-2
  • Signal Transduction
  • bcl-X Protein / genetics
  • bcl-X Protein / metabolism

Substances

  • Proto-Oncogene Proteins c-bcl-2
  • Antineoplastic Agents
  • bcl-X Protein
  • Myeloid Cell Leukemia Sequence 1 Protein