Biology subjects

Ciciro, Y.

Publications and source records attributed to Ciciro, Y..

3 recordsLinked to original sources

bioRxiv2025

Integrated in silico and in vitro approaches identify SNX.2112 as a drug vulnerability in t(7;12) AML stem-like cells

The t(7;12) translocation is a chromosomal rearrangement characteristic of infant Acute Myeloid Leukemia (AML). It arises in utero and results in ectopic overexpression of homeobox gene MNX1. Using a 3-dimensional (3D) model of blood development, we recently showed that t(7;12)-AML originates at the endothelial-to-hematopoietic transition, explaining its characteristic gene expression signature. Herein, we employ that signature to interrogate the transcriptional profiles of hundreds of human cell lines against the GDSC database of drug sensitivities to identify candidate drugs against t(7;12)-AML. We employ a cell line in which we engineered t(7;12) and systematically test the candidate drugs by cell surface phenotype and clonogenic assays. Importantly, we identify HSP90 inhibitor SNX.2112 as a potential therapeutic agent against t(7;12)-AML. SNX.2112 selectively eliminates colony-initiating leukemia progenitors in vitro and decreases MNX1 expression, effects recapitulated by other HSP90 inhibitors. SNX.2112 acts at least partly through destabilisation of STAT5 signalling. Critically, SNX.2112-differential signatures uniquely map to progenitors with hemato-endothelial characteristics in t(7;12)-AML patient blasts, suggesting targeting of leukemia-initiating cells. Combinatorial treatment with chemotherapeutic agents indicates synergy, suggesting SNX.2112 potential as a targeted and cytotoxicity-sparing therapeutic approach. Overall, we successfully use an integrated computational and multi-model experimental approach to identify a drug vulnerability of t(7;12)-AML. Key pointsO_LIClassifier-based in silico drug screening identifies vulnerabilities of t(7;12)-infant leukemia C_LIO_LI2D and 3D models of t(7;12)-leukemia match HSP90 inhibition cellular and molecular responses to candidate leukemia stem cells in t(7;12) patient analysis. C_LI

cancer biology↗

bioRxiv2025

A CDCA2 - MYC positive feedback loop controls cancer cells survival

MYC transcription factors are encoded by a small family of genes which include, in addition to the prototype member MYC, MYCN and MYCL. The majority of human cancers display expression alterations of MYC genes and their products, making this group of oncoproteins among the most relevant therapeutic targets in oncology. MYC is regulated at multiple levels, and protein phosphorylation is a critical mechanism used by the cell to modulate MYC stability and activity. Although there is a reasonable knowledge of the kinases required for MYC modifications, the counteracting phosphatases have been relatively understudied. Here we have investigated the role of the chromatin remodelling factor and protein phosphatase 1 (PP1) regulatory subunit CDCA2, also known as RepoMan, in the regulation of MYC proteins in cancer cells. Using RNA interference and regulatable degron-mediated degradation of CDCA2, we demonstrate that the PP1 subunit is required for MYC and MYCN stabilisation and viability of triple negative breast cancer, neuroblastoma and colon cancer cells. Proximity ligation assays indicate that both MYC and MYCN are in close proximity of CDCA2 in vivo. Furthermore, chromatin immunoprecipitation data and promoter mutation studies establish that CDC2A is a bone-fide MYC target gene in cancer cells, revealing a reciprocal regulatory loop that could be exploited for therapeutic purposes.

cell biology↗

bioRxiv2022

Engineered model of t(7;12)(q36;p13) AML recapitulates patient-specific features and gene expression profiles

Acute myeloid leukaemia carrying the translocation t(7;12)(q36;p13) is an adverse-risk leukaemia uniquely observed in infants. Despite constituting up to 30% of cases in under 2-year-olds, it remains poorly understood. Known molecular features are ectopic overexpression of the MNX1 gene and generation of a fusion transcript in 50% of patients. Lack of research models has hindered understanding of t(7;12) biology, which has historically focused on MNX1 overexpression rather than the cytogenetic entity itself. Here, we employed CRISPR/Cas9 to generate t(7;12) in the human K562 cell line, and in healthy CD34+ haematopoietic progenitors where the translocation was not sustained in long-term cultures or through serial replating. In contrast, in K562 cells, t(7;12) was propagated in self-renewing clonogenic assays, with sustained myeloid bias in colony formation and baseline depletion of erythroid signatures. Nuclear localisation analysis revealed repositioning of the translocated MNX1 locus to the interior of t(7;12)-harbouring K562 nuclei - a known phenomenon in t(7;12) patients which associates with ectopic overexpression of MNX1. Crucially, the K562-t(7;12) model successfully recapitulated the transcriptional landscape of t(7;12) patient leukaemia. In summary, we engineered a clinically-relevant model of t(7;12) acute myeloid leukaemia with the potential to unravel targetable molecular mechanisms of disease.

cancer biology↗