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Biology subjects

Wilkerson, M. D.

Publications and source records attributed to Wilkerson, M. D..

4 recordsLinked to original sources

Integrated proteogenomics uncovers ancestry-specific and shared molecular drivers in localized prostate cancer

Our integrative proteogenomics (genome, proteome and phosphoproteome) of localized prostate cancer (PCa) in an equal-access Military Health System patient cohort (57 Black and 55 White) revealed significant ancestry-associated differences. Somatic and germline regulatory differences converged on androgen, metabolic, PI3K/AKT/mTOR, and DNA damage response (DDR) pathways, with ancestry-specific immune- and stromal-associated signals. Black patients displayed greater genomic variability, enhanced androgen response, fatty-acid metabolism, and epithelial-mesenchymal transition, while White patients showed prevalent DDRG alterations, activated oncogenic signaling (MYC, E2F, mTORC1), and cell cycle regulation. Phosphoproteomics highlighted distinct kinase activities and candidate druggable dependencies. Multiomics integration revealed three exploratory tumor subtypes whose distinct biological programs were reproducibly validated. Ancestry-associated eQTLs supported inherited regulation of the proteome independent of CNAs. Ancestry-specific CNA and protein panels improved progression risk prediction beyond PSA and pathology models. These findings provide a framework for ancestry-informed prognostic models and generate testable hypotheses for precision therapies to reduce outcome disparities.

cancer biology↗

Lung Adenocarcinoma Just Desserts: An Expanding Pie of Activating Oncogenes or a Layer Cake of Integrated Alterations

The molecular landscape of lung adenocarcinoma (LUAD) is often summarized as a "pie chart" of driver oncogenes, suggesting identification and targeting of oncogenic drivers is the best clinical approach. However, this model oversimplifies LUAD biology. Patients with identical RAS or RAF mutations exhibit heterogeneous signaling influenced by co-mutations, transcriptional programs, and lineage context. We propose a hierarchical framework integrating oncogenes within cellular context by examining canonical EGFR mutations. We defined an EGFR mutation signature (mSig) by identifying differentially expressed genes in EGFR-mutant LUADs. Semi-supervised clustering and machine learning models were used to test performance and reproducibility across independent datasets. We analyzed molecular subtypes, lineage markers, co-occurring mutations, and candidate drug targets in EGFR-mSig positive (+) versus negative (-) tumors. The EGFR mSig showed robust classification performance across datasets (AUROC = 0.83-0.95; mean NPV = 96.3%). Validated unsupervised gene expression subtypes and lung lineage markers were closely aligned with EGFR mSig status. mSig(+) tumors were identified, even in tumors without EGFR mutations. A subset of canonical RAS mutations mirrored the EGFR mutation pattern. EGFR-mutant/mSig(-) tumors were enriched for non-Bronchioid subtypes and had co-mutations in TP53 or RAS. Coordinated mutations were identified including RAS, KEAP1, STK11, TP53, and CDKN2A, supportive of prior reports. In sum, novel EGFR mSig that captures the transcriptional footprint of EGFR activation, revealed a subset of EGFR wildtype LUADs with "mutant-like" features. Lineage-informed classification highlights subtype-dependent oncogene activity and supports new therapeutic strategies. A context-specific association between RAS mutation and expression of the dual-specificity phosphatase gene DUSP4 may have therapeutic potential.

genomics↗

A spatial gene expression signature of the mouse brain post-injury at the focal point of contusion

Traumatic brain injury (TBI) results from a primary injury that impacts the brain in a spatially-dependent manner. Here we investigated the topographical relationship of early transcriptional responses to a single, focal TBI in mice by controlled cortical impact (CCI). Guided by the presence of the anterior commissure (AC) in coronal sections at the rostro-caudal point of impact, we compared gene expression changes in the neocortex (CTX) and corpus callosum-external capsule (CC-EC), striatum (STR) and AC. Injury-induced gene expression changes were detected in the CTX, CC-EC and STR but not AC and were principally segregated based on cytoarchitecture, and secondarily by proximity to the site of impact. Additionally, unbiased spatial clustering revealed a positive relationship between proximity to the impact and the number of acutely differentially expressed genes within the laminar CTX. Gene pathways for interferon gamma response and for leukocyte-mediated migration and immunity were acutely enhanced across the injured CTX, CC-EC and STR. Within 1-week post-injury, transcriptional responses to injury in the CTX and CC-EC included gene pathways for adaptive T- and B-cell mediated immunity, whereas gene expression changes in the STR were largely resolved. Next, we examined the effects of systemic depletion of neutrophils and monocytes on spatial gene expression changes in the injured brain. This led to the upregulation of gene pathways functioning in synaptic transmission and an alternating down- and then upregulation of genes functioning in ribosomal messenger RNA translation and aerobic metabolism in mitochondria. These data suggest infiltrating neutrophils and monocytes play an evolving, multifaceted role in modulating the metabolic, transcriptional, and synaptic activity of brain tissue post-injury.

neuroscience↗

A single valine to leucine switch disrupts Plasmodium falciparum AP2-G DNA binding and reveals the role of GDV1 in ap2-g activation.

Sexual commitment in Plasmodium parasites is essential for malaria transmission, yet much remains unknown about the underlying signaling events initiating sexual conversion in a subpopulation of parasites. We discovered a single valine (V2163) to leucine (L2163) mutation in an Apetala 2 (AP2) transcription factor required for P. falciparum gametocytogenesis, ap2-g that abrogates sexual differentiation and confirmed this with forward and reverse mutation editing. Mutated AP2-G.L2163 does not bind the ap2-g consensus motif, GnGTAC, or stimulate AP2-G-dependent gene transcription including autoregulation. We then used AP2-G.L2163 parasite lines as tools to demonstrate the critical role of GDV1 in the initial activation of the silent ap2-g locus during the trophozoite to schizont transition in the absence of functional AP2-G and its autoregulation. Additionally, we show that AP2-G.V is required for MSRP1 expression, which can be used to distinguish early and late sexually committed schizonts. Together this work demonstrates that valine2163 in AP2-G plays a critical role in DNA binding, highlighting the functional importance of this specific region for malaria transmission as well as the critical role of GDV1 in the initial activation of ap2-g expression and induction of sexual differentiation. The reporter lines generated allow further study of signaling pathways or screening of factors regulating sexual commitment.

microbiology↗