Cooper-Volkheimer, A. | Search bioRxiv

bioRxiv2026

CaMKK2 Identifies Biologically Aggressive Chronic Lymphocytic Leukemia and Regulates Leukemic Survival and Nurse-Like Cell Support

Background/ObjectivesIdentification of prognostic biomarkers that capture biologically aggressive disease remains a major need in chronic lymphocytic leukemia (CLL). Aberrant calcium signaling contributes to leukemic survival; however, the clinical relevance of Ca{superscript 2}/calmodulin-dependent protein kinase kinase 2 (CaMKK2), a calcium-responsive kinase, has not been defined. This study evaluated CaMKK2 as a candidate prognostic biomarker and functional regulator in CLL. MethodsCaMKK2 expression was quantified in purified CD19 CLL cells from a clinically annotated cohort balanced by immunoglobulin heavy chain variable region (IGHV) mutation status. Associations with time-to-treatment and overall survival were analyzed. Functional relevance was assessed by pharmacologic inhibition of CaMKK2 in primary CLL cells using metabolic (MTS) and apoptosis (Annexin V/PI) assays. Correlations between CaMKK2 expression and inhibitor sensitivity were determined. The impact of CaMKK2 inhibition on nurse-like cell (NLC) differentiation and macrophage-mediated leukemic support was evaluated in ex vivo culture systems. ResultsElevated CaMKK2 expression was enriched in IGHV-unmutated CLL and associated with shorter time-to-treatment and inferior overall survival. CaMKK2 inhibition reduced primary CLL viability in a dose-dependent manner and induced apoptosis, with sensitivity correlating with CaMKK2 expression levels. Inhibition also attenuated CD163 macrophage polarization and impaired NLC-mediated support of leukemic cells. ConclusionsCaMKK2 expression identifies biologically aggressive CLL and functionally contributes to leukemic persistence. These findings position CaMKK2 as a prognostically relevant biomarker with therapeutic implications, supporting further evaluation of CaMKK2-targeted strategies in high-risk CLL. Sample SummaryChronic lymphocytic leukemia (CLL) shows marked variability in clinical outcome, highlighting the need for biomarkers that identify patients at higher risk of progression and guide therapeutic strategies. Calcium signaling supports leukemia cell survival, yet the clinical relevance of the calcium-responsive enzyme CaMKK2 has not been established. In this study, we demonstrate that elevated CaMKK2 expression in patient-derived leukemia cells is associated with more aggressive disease and earlier need for treatment. Laboratory experiments further show that inhibiting CaMKK2 reduces leukemia cell survival and disrupts supportive macrophage-like cells within the tumor microenvironment. These results position CaMKK2 as a candidate prognostic biomarker that reflects biologically high-risk disease and may inform therapeutic development. Future studies are warranted to determine whether CaMKK2-based risk stratification or targeted inhibition could improve management of patients with CLL.

immunology↗

bioRxiv2025

Single cell multiomic analysis of the impact of Delta-9-tetrahydrocannabinol on HIV infected CD4 T cells

Cannabis use is prevalent among individuals living with HIV in the United States, but the impact of cannabis exposure on the reservoir of latently infected cells that persists during antiretroviral therapy (ART) remains unclear. To address this gap, we analyzed the effect of {Delta}-9-tetrahydrocannabinol (THC) on primary CD4 T cells that were latently infected with HIV. We found that THC had no detectable effect on baseline or latency reversing agent (LRA) stimulated HIV expression, or on expression of an activation marker (CD38). However, using an integrated multiomic single-cell analysis of genome-wide chromatin accessibility and gene expression, we observed altered expression of several hundred genes in HIV infected CD4 T cells after THC exposure, including transcriptional downregulation of genes involved in protein translation and antiviral pathways, indicating that THC suppresses innate immune activation in infected cells. Additionally, chromatin accessibility analysis demonstrated upregulated chromatin binding activity for the transcriptional regulator CTCF, and reduced activity for members of the ETS transcription factor family in infected cells after THC exposure. These findings provide insights into the mechanisms by which cannabis use could influence the persistence of HIV within cellular reservoirs and the molecular phenotype of latently infected cells. Further elucidation of the underlying mechanisms involved in THC-mediated changes to HIV infected cells, will lead to an improved understanding of the impact of cannabis use on the HIV reservoir. ImportanceCannabis use is common among individuals living with HIV, but the long-term effects of cannabis use on the HIV reservoir are not yet studied completely. We employed advanced single-cell technologies to reveal how cannabis components, specifically THC, influence HIV-infected immune cells and their pattern of gene expression. We found that, while THC doesnt reactivate virus in latently infected cells, it alters the molecular characteristics of these infected immune cells. These findings are important because they underscore how cannabis could regulate persistent infection in people living with HIV. Understanding these cellular changes in response to THC could be helpful for successful treatment for people living with HIV.

molecular biology↗