Biology subjects

Gibbs, Z.

Publications and source records attributed to Gibbs, Z..

3 recordsLinked to original sources

bioRxiv2026

Aberrant expression of the testis kinase TSSK6 activates FAK-STAT3 signaling to promote tumorigenic growth

Cancer-testis antigens (CTAs) are germ cell-restricted proteins aberrantly expressed in diverse malignancies, yet whether these proteins contribute to tumor progression remains poorly defined. The CTA Testis-Specific Serine Kinase 6 (TSSK6) is frequently expressed in colorectal cancer (CRC), where it promotes key hallmarks of tumor progression, including anchorage-independent growth, invasion, and in vivo tumor formation. However, the signaling network by which ectopic TSSK6 drives these phenotypes has not been established. Here, we define the signaling pathways regulated by TSSK6 in CRC cells. We demonstrate that TSSK6 promotes focal adhesion kinase (FAK) activation, leading to enhanced STAT3 Ser727 phosphorylation and increased STAT3-dependent transcription. Transcriptomic analyses revealed induction of gene programs enriched for extracellular matrix remodeling, cytoskeletal organization, adhesion, and motility in a STAT3-dependent manner. Disruption of the FAK-STAT3 signaling axis abrogated anchorage-independent growth and invasive outgrowth in a spheroid model. Collectively, these findings demonstrate that aberrant expression of a germline-restricted kinase promotes focal adhesion signaling, which activates STAT3-dependent transcriptional programs that promote anoikis resistance and invasive behavior in CRC.

cancer biology↗

bioRxiv2024

Single-cell analysis of the epigenome and 3D chromatin architecture in the human retina

Most genetic risk variants linked to ocular diseases are non-protein coding and presumably contribute to disease through dysregulation of gene expression, however, deeper understanding of their mechanisms of action has been impeded by an incomplete annotation of the transcriptional regulatory elements across different retinal cell types. To address this knowledge gap, we carried out single-cell multiomics assays to investigate gene expression, chromatin accessibility, DNA methylome and 3D chromatin architecture in human retina, macula, and retinal pigment epithelium (RPE)/choroid. We identified 420,824 unique candidate regulatory elements and characterized their chromatin states in 23 sub-classes of retinal cells. Comparative analysis of chromatin landscapes between human and mouse retina cells further revealed both evolutionarily conserved and divergent retinal gene-regulatory programs. Leveraging the rapid advancements in deep-learning techniques, we developed sequence-based predictors to interpret non-coding risk variants of retina diseases. Our study establishes retina-wide, single-cell transcriptome, epigenome, and 3D genome atlases, and provides a resource for studying the gene regulatory programs of the human retina and relevant diseases.

genomics↗

bioRxiv2023

The Cancer Testes Antigen, HORMAD1, is a Tumor-Specific Replication Fork Protection Factor

Tumors frequently activate the expression of genes that are only otherwise required for meiosis. HORMAD1, which is essential for meiotic recombination in multiple species, is expressed in over 50% of human lung adenocarcinoma cells (LUAD). We previously found that HORMAD1 promotes DNA double strand break (DSB) repair in LUAD. Here, we report that HORMAD1 takes on an additional role in protecting genomic integrity. Specifically, we find HORMAD1 is critical for protecting stalled DNA replication forks in LUAD. Loss of HORMAD1 leads to nascent DNA degradation, an event which is mediated by the MRE11-DNA2-BLM pathway. Moreover, following exogenous induction of DNA replication stress, HORMAD1 deleted cells accumulate single stranded DNA (ssDNA). We find that these phenotypes are the result of a lack of RAD51 and BRCA2 loading onto stalled replication forks. Ultimately, loss of HORMAD1 leads to increased DSBs and chromosomal aberrations in response to replication stress. Collectively, our data support a model where HORMAD1 expression is selected to mitigate DNA replication stress, which would otherwise induce deleterious genomic instability.

cancer biology↗