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Di Cristofano, A.

Publications and source records attributed to Di Cristofano, A..

2 recordsLinked to original sources

A zebrafish xenotransplant model of anaplastic thyroid cancer to study the tumor microenvironment and innate immune cell interactions in vivo.

Anaplastic thyroid cancer (ATC) is a rare malignant subtype of thyroid cancer. While ATC is rare it accounts for a disproportionately high number of thyroid cancer-related deaths. Here we developed an ATC xenotransplant model in zebrafish larvae, where we can study tumorigenesis and therapeutic response in vivo. Using both mouse (T4888M) and human (C643) derived fluorescently labeled ATC cell lines we show these cell lines display different engraftment rates, mass volume, proliferation, and angiogenic potential. Next, using a PIP-FUCCI reporter to track proliferation in-vivo we observed cells in each phase of the cell cycle. Additionally, we performed long-term non-invasive intravital microscopy over 48 hours to understand cellular dynamics in the tumor microenvironment at the single cell level. Lastly, we tested a well-known mTOR inhibitor to show our model could be used as an effective screening platform for new therapeutic compounds. Altogether, we show that zebrafish xenotransplants make a great model to study thyroid carcinogenesis and the tumor microenvironment, while also being a suitable model to test new therapeutics in vivo. SUMMARY STATEMENTAnaplastic thyroid cancer xenotransplant model in zebrafish larvae to study thyroid cancer tumorigenesis and tumor microenvironment. Using confocal microscopy to understand cell cycle progression, interactions with the innate immune system, and test therapeutic compounds in vivo.

cancer biology↗

Anaplastic Thyroid Cancer Cells Upregulate Mitochondrial One-Carbon Metabolism To Meet Purine Demand, Eliciting A Critical Targetable Vulnerability

Anaplastic thyroid cancer (ATC) is one of the most aggressive and lethal tumor types, characterized by loss of differentiation, epithelial-to-mesenchymal transition, extremely high proliferation rate, and generalized resistance to therapy. To identify novel relevant, targetable molecular alterations, we analyzed gene expression profiles from a genetically engineered ATC mouse model and from human patient datasets, and found consistent upregulation of genes encoding enzymes involved in the one-carbon metabolic pathway, which uses serine and folates to generate both nucleotides and glycine. Genetic and pharmacological inhibition of SHMT2, a key enzyme of the mitochondrial arm of the one-carbon pathway, rendered ATC cells glycine auxotroph and led to significant inhibition of cell proliferation and colony forming ability, which was primarily caused by depletion of the purine pool. Notably, these growth-suppressive effects were significantly amplified when cells were grown in the presence of physiological types and levels of folates. Genetic depletion of SHMT2 dramatically impaired tumor growth in vivo, both in xenograft models and in an immunocompetent allograft model of ATC. Together, these data establish the upregulation of the one-carbon metabolic pathway as a novel and targetable vulnerability of ATC cells, which can be exploited for therapeutic purposes.

cancer biology↗