Biology subjects

Stiller, M.

Publications and source records attributed to Stiller, M..

3 recordsLinked to original sources

bioRxiv2023

TERT expression is associated with metastasis from thin primaries, exhausted CD4+ T cells in melanoma and with DNA repair across cancer entities

Telomerase reverse transcriptase (TERT) promoter mutations occur frequently in cancer, have been associated with increased TERT expression and cell proliferation, and could potentially influence therapeutic regimens for melanoma. As the role of TERT expression in malignant melanoma and the non-canonical functions of TERT remain understudied, we aimed to extend the current knowledge on both types of TERT alterations with respect to survival, further clinical and molecular parameters. Using multivariate models, TERT alterations were not consistently associated with survival in melanoma cohorts under immune checkpoint inhibition. The presence of CD4+ T cells increased with TERT expression and correlated with the expression of exhaustion markers. While the frequency of promoter mutations did not change with Breslow thickness, TERT expression was increased in metastases arising from thinner primaries. Enrichment analyses of single-cell RNA-seq showed TERT expression is associated with genes involved in cell migration and dynamics of the extracellular matrix, supporting the role of TERT during invasion and metastasis. Co-regulated genes in several bulk tumors and single-cell RNA-seq cohorts also indicated non-canonical functions of TERT related to mitochondrial DNA stability and nuclear DNA repair in line with increased TERT expression during chromothripsis (PCAWG cohort) and under hypoxic conditions (PCAWG and SKCM cohorts). Also in glioblastoma (Klughammer and PCAWG cohorts), TERT was co-expressed with DNA repair genes. Our results thus indicate a relevance of TERT expression in melanoma metastasis, T cell dysfunction and DNA repair across cancer entities. SignificanceIn addition to the frequently occurring TERT promoter mutations, we test TERT expression with respect to clinical and molecular associates, extending the canonical role of TERT in melanoma and other cancer entities.

cancer biology↗

bioRxiv2022

Interactive webtool for analyzing drug sensitivity and resistance associated with genetic signatures of cancer cell lines

A wide therapeutic repertoire has become available to oncologists including radio- and chemotherapy, small molecules and monoclonal antibodies. However, drug efficacy can be limited by genetic changes that allow cancer cells to escape therapy. Here, we designed a webtool that facilitates the data analysis of the Genomics of Drug Sensitivity in Cancer (GDSC) database on 265 approved compounds in association with a plethora of genetic changes documented for 1001 cell lines in the Cancer Cell Line Encyclopedia (CCLE, cBioPortal). The webtool computes odds ratios of drug resistance for a queried set of genetic alterations. It provides results on the efficacy of single or groups of compounds assigned to cellular signaling pathways. Using this webtool we replicated known genetic drivers and identified new candidate genes, germline variants, co-mutation, and pharmacogenomic modifiers of both cancer drug resistance and drug repurposing. Webtool availability: https://tools.hornlab.org/GDSC/. Author SummaryTumors develop through uncontrolled cell growth enabled by various alterations that create tumor heterogeneity. Changes of the genome and thus cancer cells cause every patient to react differently to drugs and can lead to drug resistance in cancer therapies. To overcome drug resistance, researchers focus on developing personalized therapies. Here, we provide a straightforward tool to test public in vitro drug sensitivity data on a range of drugs for custom analyses of genetic changes. This may inform the identification of potential drug candidates and improve our understanding of signaling pathways as we can test drug response with custom sets of genetic changes according to specific research questions. The tool and underlying code can be adapted to larger drug response datasets and other data types, e.g. metabolic data, to help structure and accommodate the increasingly large biomedical knowledge base.

cancer biology↗

bioRxiv2017

A new genus of horse from Pleistocene North America

The extinct \"New World stilt-legged\", or NWSL, equids constitute a perplexing group of Pleistocene horses endemic to North America. Their slender distal limb bones resemble those of Asiatic asses, such as the Persian onager. Previous palaeogenetic studies, however, have suggested a closer relationship to caballine horses than to Asiatic asses. Here, we report complete mitochondrial and partial nuclear genomes from NWSL equids from across their geographic range. Although multiple NWSL equid species have been named, our palaeogenomic and morphometric analyses support the idea that there was only a single species of middle to late Pleistocene NWSL equid, and demonstrate that it falls outside of crown group Equus. We therefore propose a new genus, Haringtonhippus, for the sole species H. francisci. Our combined genomic and phenomic approach to resolving the systematics of extinct megafauna will allow for an improved understanding of the full extent of the terminal Pleistocene extinction event.

paleontology↗