Biology subjects

Satterlee, A. B.

Publications and source records attributed to Satterlee, A. B..

4 recordsLinked to original sources

bioRxiv2025

Combinatorial Treatment of Glioblastoma with Temozolomide (TMZ) Plus 55-Ethynyl-2-deoxyuridine (EdU)

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor in adults, with incidence peaking in later life. It is commonly treated with surgery followed by administration of ionizing radiation and the DNA alkylating agent temozolomide (TMZ). Even though this regimen confers some progression-free survival, there is essentially no cure with the median survival with the standard of care being about 12 months. Currently, several alternative approaches are being developed to improve upon this outcome. We have already shown EdU alone effectively treats GBM, and we now study efficacy of TMZ+EdU combination therapy. TMZ+EdU significantly improves antitumor efficacy compared to either single-agent therapy against GBM cell lines in vitro, against three different orthotopic GBM xenograft models, and against passage-zero patient GBM tumor tissues engrafted within an organotypic brain slice culture (OBSC)-based platform. Together, these data suggest that EdU could be effective alongside standard of care TMZ in patients with GBM. STATEMENT OF SIGNIFICANCE (50-WORD)By simultaneously engaging distinct DNA repair pathways, combination of TMZ and EdU produced unprecedented survival benefits and synergistic effects in preclinical GBM models, offering a promising new avenue in the treatment of GBM.

cancer biology↗

bioRxiv2024

Auto-loaded TRAIL-exosomes derived from induced neural stem cells for brain cancer therapy

Transdifferentiation (TD), a somatic cell reprogramming process that eliminates pluripotent intermediates, creates cells that are ideal for personalized anti-cancer therapy. Here, we provide the first evidence that extracellular vesicles (EVs) from TD-derived induced neural stem cells (Exo-iNSCs) are an efficacious treatment strategy for brain cancer. We found that genetically engineered iNSCs generated EVs loaded with the tumoricidal gene product TRAIL at nearly twice the rate as their parental fibroblasts, and the TRAIL produced by iNSCs were naturally loaded into the lumen of EVs and arrayed across their outer membrane (Exo-iNSC-TRAIL). Uptake studies in ex vivo organotypic brain slice cultures showed Exo-iNSC-TRAIL selectively accumulates within tumor foci, and co-culture assays showed that Exo-iNSC-TRAIL killed metastatic and primary brain cancer cells more effectively than free TRAIL. In an orthotopic mouse model of brain cancer, Exo-iNSC-TRAIL reduced breast-to-brain tumor xenografts around 3000-fold greater than treatment with free TRAIL, with all Exo-iNSC-TRAIL treated animals surviving through 90 days post-treatment. In additional in vivo testing against aggressive U87 and invasive GBM8 glioblastoma tumors, Exo-iNSC-TRAIL also induced a statistically significant increase in survival. These studies establish a new easily generated, stable, tumor-targeted EV to efficaciously treat multiple forms of brain cancer.

cancer biology↗

bioRxiv2024

A Novel ex-vivo platform for personalized treatment in metastatic ovarian cancer.

The lack of functional precision models that recapitulate the pathology and structure/function relationship of advanced ovarian cancer (OC) within an appropriate anatomic setting constitutes a hurdle on the path to developing more reliable therapies and matching those therapies with the right patients. Here, we developed and characterized an Organotypic Mesentery Membrane Culture (OMMC) model as a novel ex-vivo platform where freshly resected human patient OC tumor tissue or established cell lines are seeded directly atop living intact rat mesenteric membranes, rapidly engraft, and enable functional assessment of treatment response to FDA-approved standard care of treatment as single and combination drug therapies within just five days. This study showed successful survival of dissected mesentery tissue, survival and engraftment of tumor cells and patient tumor tissue seeded on OMMCs, mesentery-tumor cell interaction, and quantification of tumor response to treatment and off-target toxicity. Summarized "drug sensitivity scores", using a multi-parametric algorithm, were also calculated for each patients treatment response, enabling us to suggest the most effective therapeutic option. Finally, we compared drug sensitivity results from patient tumor tissue on OMMCs to matched outcomes of individual patients in the clinic and identified positive correlations in drug sensitivity, beginning to validate the functionality of OMMCs as a functional predictor of treatment response. Summary sentenceWe have successfully developed and characterized a novel ex-vivo platform for personalized treatment of metastatic ovarian cancer.

cancer biology↗

bioRxiv2023

Trans-Lesion Synthesis and Mismatch Repair Pathway Crosstalk Defines Chemoresistance and Hypermutation Mechanisms in Glioblastoma

Almost all Glioblastoma (GBM) are either intrinsically resistant to the chemotherapeutical drug temozolomide (TMZ) or acquire therapy-induced mutations that cause chemoresistance and recurrence. The genome maintenance mechanisms responsible for GBM chemoresistance and hypermutation are unknown. We show that the E3 ubiquitin ligase RAD18 (a proximal regulator of TLS) is activated in a Mismatch repair (MMR)-dependent manner in TMZ-treated GBM cells, promoting post-replicative gap-filling and survival. An unbiased CRISPR screen provides a new aerial map of RAD18-interacting DNA damage response (DDR) pathways deployed by GBM to tolerate TMZ genotoxicity. Analysis of mutation signatures from TMZ-treated GBM reveals a role for RAD18 in error-free bypass of O6mG (the most toxic TMZ-induced lesion), and error-prone bypass of other TMZ-induced lesions. Our analyses of recurrent GBM patient samples establishes a correlation between low RAD18 expression and hypermutation. Taken together we define novel molecular underpinnings for the hallmark tumorigenic phenotypes of TMZ-treated GBM.

cancer biology↗