bioRxiv Science⌕ Search

Biology subjects

Vleminckx, L.

Publications and source records attributed to Vleminckx, L..

2 recordsLinked to original sources

PERTURBATION OF THE AMINO ACID STRESS RESPONSE PATHWAY EXPOSES A METABOLIC VULNERABILITY IN MULTIPLE AGGRESSIVE CANCER SUBTYPES

Cancer cells frequently experience nutrient limitation and depend on adaptive stress-response pathways to maintain metabolic homeostasis. Here, we show that pharmacological perturbation of amino acid stress signaling exerts broad anti-tumor activity across multiple aggressive malignancies, including acute lymphoblastic leukemia, acute myeloid leukemia, triple-negative breast cancer, ovarian cancer, and neuroblastoma. Sensitivity to pathway modulation is associated with a chronic stress-adapted metabolic state marked by constitutive amino acid response signaling, elevated NFE2L2 expression, and reduced mitochondrial abundance despite evidence of efficient oxidative metabolism. Mechanistically, we demonstrate that the ATP-competitive compound GCN2-IN-6 does not phenocopy genetic GCN2 suppression and exhibits context-dependent effects on the amino acid stress response. Nevertheless, tumors experiencing chronic metabolic stress remain exquisitely sensitive to disruption of this adaptive network, regardless of whether signaling is perturbed through canonical inhibition or paradoxical activation. Collectively, our findings identify chronic metabolic stress adaptation as an actionable vulnerability and establish off-balancing amino acid stress signaling as a therapeutic strategy across multiple cancer types

cancer biology↗

Targeting replication stress in neuroblastoma by exploiting the synergistic potential of second generation RRM2 and CHK1 inhibitors

Tumor cells often cope with elevated levels of replication stress (RS) causing increased dependency on ATR-CHK1 signalling. We previously presented RRM2, the regulatory component of the ribonucleotide reductase (RNR) enzyme, as novel dependency in neuroblastoma, in keeping with its role in RS resistance. We identified strong synergism for combined RRM2-CHK1 inhibition using the iron chelator triapine and prexasertib respectively. To obtain direct RNR targeting, we evaluated a novel inhibitor, TAS1553, specifically disrupting the RNR complex in this study. Treatment with TAS1553 impedes cell growth and induces enhanced RS, DNA damage and apoptosis. We demonstrated strong synergism between TAS1553 the CHK1 inhibitors prexasertib and SRA737 in both NB and sarcoma cell lines, underscoring the broad clinical potential of combinatorial RRM2-CHK1 inhibition. Transcriptome profiling demonstrated strong overlap between the different RRM2-CHK1 treatments and revealed differential expression of RNA splicing components, opening new perspectives for combination treatments using splicing inhibitors. Altogether, this study paves the way for further preclinical testing of second generation RRM2 and CHK1 inhibitors such as TAS1553 and SRA737 in neuroblastoma and sarcomas.

cancer biology↗