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Biology subjects

Glaziou, Q.

Publications and source records attributed to Glaziou, Q..

2 recordsLinked to original sources

Proteomic profiling reveals pleiotropic antimetabolite activity of triciribine in acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) exhibits marked genetic and metabolic heterogeneity that limits the efficacy of targeted therapies. Antimetabolite strategies remain central to ALL treatment, yet the mechanisms underlying differential drug sensitivity are incompletely defined. Here, we investigated the activity of the purine analog triciribine (TCN) across diverse ALL cellular models. We find that TCN exerts potent cytotoxic effects in multiple ALL cell lines, exceeding those observed with canonical Akt inhibitors in our datasets. Phosphoproteomic analyses indicate that, at early time points, TCN does not primarily suppress Akt signaling but instead induces transient pathway activation accompanied by inhibition of cyclin-dependent kinases in both sensitive and resistant cells. The monophosphorylated metabolite TCN-P represents the predominant intracellular species and requires adenosine kinase (ADK) for activity, with ADK protein levels positively correlating with TCN sensitivity in both cell lines and primary patient samples. Using Proteome Integral Solubility Alteration profiling, we identify candidate protein interactions of TCN-P distributed across multiple cellular pathways, including nucleotide metabolism, DNA replication, and protein synthesis. These interactions are accompanied by impaired purine biosynthesis, DNA damage, translational stress, and cell-cycle arrest, as supported by time-course quantitative proteomics and immunoblot analyses. Together, these findings characterize triciribine as an antileukemic agent with pleiotropic antimetabolite activity in ALL and highlight ADK-dependent metabolism as a key determinant of therapeutic sensitivity, suggesting that ADK levels may serve as a predictive biomarker to stratify patients for triciribine-based precision treatment strategies.

cancer biology↗

IL-27 neutralization to modulate the tumor microenvironment and increase immune checkpoint immunotherapy efficacy

In this study, we investigated the role of interleukin-27 (IL-27) as a regulator of the tumor immune microenvironment (TME) and its impact on the CD39/adenosine metabolic axis. The effects of IL-27 neutralization were evaluated using both in vivo MC38 murine colon adenocarcinoma mode and in vitro human macrophage models. In vivo, we analyzed how IL-27 blockade affects tumor growth and the phenotype of infiltrating immune cells, particularly regarding their CD39 expression. In vitro, we focused on the impact of IL-27 during human macrophage differentiation using flow cytometry, metabolic analysis, and functional assays. Our findings demonstrate that within tumor IL-27 is a major driver of the immunosuppressive phenotype in both murine and human immune cells. Mechanistically, IL-27 induces high levels of the ectonucleotidase CD39, promoting an adenosine-mediated suppressive environment. In vivo, IL-27 blockade led to a broad downregulation of CD39 on both myeloid cells and exhausted T cells. This remodeling of the TME significantly attenuated tumor growth and enhanced the efficacy of anti-PD-L1 checkpoint therapy. We confirm that neutralizing IL-27 prevents the acquisition of immunoregulatory markers in human macrophages and induces significant metabolic reprogramming. Collectively, our results highlight the IL-27/CD39 axis as a key mechanism of immune evasion. We suggest that targeting IL-27 is a promising strategy to reprogram the metabolic and cellular state of the tumor microenvironment, improving the effectiveness of cancer immunotherapy.

immunology↗