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Guscetti, F.

Publications and source records attributed to Guscetti, F..

3 recordsLinked to original sources

Multiomic profiling of human and canine soft-tissue sarcomas reveals extensive molecular homology across species and identifies clinically relevant subgroups

Soft-tissue sarcoma (STS) are rare and heterogeneous mesenchymal tumours with over 100 recognized human subtypes. Despite advances in cytogenetic and molecular characterization, diagnostic precision and therapeutic options remain limited for most subtypes. Spontaneously occurring canine STS could represent valuable translational models, due to their higher incidence and clinical similarity to human counterparts. However, molecular cross-species comparisons of specific subtypes are largely missing. Here, we performed a tissue-resolved, cross-species analysis of tumour and matched adjacent normal tissue (NT) in human and canine fibrosarcoma (FSA) and myxofibrosarcoma (MFS) by laser-capture microdissection of FFPE specimens combined with RNAseq and LC-MS/MS. Multimodal profiling revealed FSA and MFS to represent a molecular continuum rather than distinct entities in both species, resulted in identification of clinically relevant subgroups based on immune activation, proliferative activity and copy number alterations, and identified a novel canine STS subtype associated with a gene fusion. Moreover, our analyses revealed cross-species conserved transcriptomic and proteomic alterations distinguishing tumour from NT, including pathways linked to extracellular matrix remodelling, immune modulation, and cell proliferation. These data establish the first comprehensive molecular comparison of canine and human FSA and MFS, highlight the translational relevance of canine models, and identify candidate biomarkers for diagnostic refinement and development of targeted therapeutic modalities.

cancer biology↗

Canine Mammary Tumours (CMTs) exploit Mitochondrial Cholesterol for aggressive reprogramming

In human breast cancer the mitochondrial translocator protein (TSPO) aids pro-survival cellular response by facilitating the formation of mitochondrial contact sites with the nucleus termed Nucleus Associated Mitochondria (NAM). Here, we show that TSPO positively associates with the aggressiveness of tissues and cells isolated from Canine Mammary Tumours (CMTs). TSPO is also readily upregulated in reprogrammed mammary tumour cells following long-term deprivation of oestrogen or exposure to the endocrine chemotherapeutic (ET) agent Tamoxifen. The latter triggers mitochondrial handling of cholesterol which is facilitated by TSPO whose upregulation reduces susceptibility to Tamoxifen. TSPO binding ligands boost, on the other hand, the efficacy of Tamoxifen and Chemotherapy agents. In aggressive canine mammary tumour cells, TSPO repression impairs the NF-kB pattern thus confirming the pro-survival role of the NAM uncovered in the human counterpart. Mitochondrial cholesterol handling via TSPO emerges therefore as a signature in the aggressive reprogramming of CMTs thus advancing our understanding of the molecular mechanisms underpinning this pathology. A novel target mechanism to improve bio-marking and therapeutic protocols is here proposed.

cancer biology↗

Pro-apoptotic and anti-invasive properties underscore the tumor suppressing impact of myoglobin on subset of human breast cancer cells

Expression of myoglobin (MB), well known as the oxygen storage and transport protein of myocytes, is a novel hallmark of the luminal subtype in breast cancer patients and correlates with better prognosis. The mechanisms by which MB impacts mammary tumorigenesis are hitherto unclear. We aimed to unravel this role, by using CRISPR/Cas9 technology to generate MB-deficient clones of MCF7 and SKBR3 breast cancer cell lines and subsequently characterize them by transcriptomics plus molecular and functional analyses. As main findings, loss of MB, at normoxia, upregulated the expression of cell cyclins and increased cell survival while it prevented apoptosis in MCF7 cells. Also, MB-deficient cells were less sensitive to doxorubicin but not ionizing radiation. Under hypoxia, loss of MB enhanced partial epithelial to mesenchymal transition, thus augmenting the migratory and invasive cell behavior. Notably, in human invasive mammary ductal carcinoma tissues, MB and apoptotic marker levels were positively correlated. In addition, MB protein expression in invasive ductal carcinomas was associated with a positive prognostic value, independent of the known tumor suppressor p53. In conclusion, we provide multiple lines of evidence that endogenous MB in cancer cells by itself exerts novel tumor-suppressive roles through which it can reduce cancer malignancy.

cancer biology↗