Biology subjects

Neel, B.

Publications and source records attributed to Neel, B..

7 recordsLinked to original sources

bioRxiv2026

SHP2 binds directly to SOS1 to enable RAS activation

The protein-tyrosine phosphatase SHP2 (PTPN11) regulates growth factor- and cytokine-induced RAS/ERK MAP kinase (MAPK) pathway activation, and aberrant SHP2 function causes developmental disorders and cancer1-5. It is widely believed that the catalytic activity of SHP2 is essential for pathway activation1,4,6-8. This view has shaped our interpretation of how germline PTPN11 mutations cause Noonan Syndrome (NS) and NS with Multiple Lentigines (NS-ML)2,9 and how somatic mutations contribute to myeloproliferative neoplasms and solid tumors1. Here we identify a previously undetected, protein-tyrosine phosphatase (PTP) activity-independent mechanism that revises our understanding of how SHP2 promotes RAS/ERK activation. We find that certain mutations of the nucleophilic cysteine that abolish catalytic activity still promote RAS/ERK pathway activation in normal and neoplastic mammalian cells, zebrafish embryos, and mice. Structural studies show that the SHP2 PTP domain binds directly to the Son of Sevenless 1 (SOS1) Dbl homology (DH) domain. Proximity labeling and super-resolution microscopy demonstrate that SHP2/SOS1 interaction occurs in cells and facilitates SOS1 translocation to the plasma membrane to form clusters. Our results overturn decades of dogma on SHP2 regulation of the RAS/ERK pathway and provide new insights into the mechanism of action of disease-associated PTPN11 mutations.

Cancer Biology↗

bioRxiv2026

Pan-cancer proteogenomic interrogation of the Ubiquitin Proteasome System

Somatic mutations rewire the ubiquitin-proteasome system (UPS) to support tumor growth, but the proteome-wide consequences of cancer-driver alterations on UPS composition remain incompletely understood. Using harmonized proteogenomic data from up to 11 CPTAC cohorts, we performed an integrated pan-cancer analysis of UPS protein dysregulation, prognostic associations, and mutation-driven remodeling. We show that mRNA poorly predicts UPS protein abundance, that a defined set of E3 ligases is recurrently dysregulated across cancers, and that somatic mutations (most strikingly TP53 loss) produce coherent UPS protein-quantitative trait locus (pQTL) signatures. Two case studies (UBR5 and TRIM28) illustrate orthogonal modes of UPS rewiring: a mutation-driven axis in which TP53-mutant tumors elevate UBR5 to support replication stress tolerance, and a lineage-driven axis in which TRIM28 engages tissue-restricted regulatory networks with opposing prognostic effects in glioblastoma versus head and neck cancer. Each axis exposes context-specific therapeutic vulnerabilities, including sensitivity to DNA damage response inhibitors (UBR5-high) and lineage-specific drug responses (TRIM28-high). Together, these analyses define a mechanistic framework for how cancer-driver mutations reshape proteostasis through the UPS and nominate mutation- and lineage-defined dependencies for precision degrader therapy. The harmonized pan-tissue atlas and the UbiDash interactive resource that underpin parts of this analysis are reported in our companion paper1. HighlightsO_LIProteome-centric profiling reveals UPS dysregulation invisible at the transcript level across human cancers C_LIO_LIPan-cancer differential expression identifies recurrently dysregulated E3 ligases with prognostic value C_LIO_LIGenome-wide pQTL analysis uncovers mutation-driven UPS remodeling, with TP53 loss as a dominant driver C_LIO_LIUBR5 and TRIM28 define orthogonal mutation- and lineage-driven axes of UPS rewiring with distinct therapeutic vulnerabilities C_LI

systems biology↗

bioRxiv2023

In vivo metabolomics identifies CD38 as an emergent vulnerability in LKB1-mutant lung cancer

LKB1/STK11 is a serine/threonine kinase that plays a major role in controlling cell metabolism, resulting in potential therapeutic vulnerabilities in LKB1-mutant cancers. Here, we identify the NAD+ degrading ectoenzyme, CD38, as a new target in LKB1-mutant NSCLC. Metabolic profiling of genetically engineered mouse models (GEMMs) revealed that LKB1 mutant lung cancers have a striking increase in ADP-ribose, a breakdown product of the critical redox co-factor, NAD+. Surprisingly, compared with other genetic subsets, murine and human LKB1-mutant NSCLC show marked overexpression of the NAD+-catabolizing ectoenzyme, CD38 on the surface of tumor cells. Loss of LKB1 or inactivation of Salt-Inducible Kinases (SIKs)--key downstream effectors of LKB1-- induces CD38 transcription induction via a CREB binding site in the CD38 promoter. Treatment with the FDA-approved anti-CD38 antibody, daratumumab, inhibited growth of LKB1-mutant NSCLC xenografts. Together, these results reveal CD38 as a promising therapeutic target in patients with LKB1 mutant lung cancer. SIGNIFICANCELoss-of-function mutations in the LKB1 tumor suppressor of lung adenocarcinoma patients and are associated with resistance to current treatments. Our study identified CD38 as a potential therapeutic target that is highly overexpressed in this specific subtype of cancer, associated with a shift in NAD homeostasis.

cancer biology↗

bioRxiv2022

Inflammation in the tumor-adjacent lung as a predictor of clinical outcome in lung adenocarcinoma

Early-stage lung adenocarcinoma is typically treated by surgical resection of the tumor. While in the majority of cases surgery can lead to cure, approximately 30% of patients progress. Despite intense efforts to map the genetic landscape of early-stage lung tumors, there has been limited success in discovering accurate biomarkers that can predict clinical outcomes. Meanwhile, the role of the tumor-adjacent tissue in cancer progression has been largely ignored. To test whether tumor-adjacent tissue can be informative of progression-free survival and to probe the underlying molecular pathways involved, we designed a multi-omic study in both tumor and matched tumor-adjacent histologically normal lung tissue from the same patient. Our study includes 143 treatment naive stage I cases with long-term patient follow-up and is, to our knowledge, the largest such study with the longest follow-up. We performed a comprehensive histologic characterization of all tumors, mapped the mutational landscape and probed the transcriptome of both tumor and adjacent normal tissue. We evaluated the predictive power of each data modality and showed that the transcriptome of tumor-adjacent histologically normal lung tissue is the only reliable predictor of clinical outcome. Unbiased discovery of co-expressed gene modules revealed that inflammatory pathways are upregulated in the tumor-adjacent tissue of patients at high risk for disease progression. Furthermore, single-cell transcriptome analysis in the tumor-adjacent lung demonstrated that progression-associated inflammatory signatures were broadly expressed by both immune and non-immune cells including mesothelial cells, alveolar type 2 cells and fibroblasts, CD1 dendritic cells and MAST cells. Collectively, our studies suggest that molecular profiling of tumor-adjacent tissue can identify patients that are at high risk for disease progression.

bioinformatics↗

bioRxiv2019

Activated thiol Sepharose-based proteomic approach to globally quantify protein oxidation

Reactive oxygen species (ROS) can act as second messengers for various signaling pathways, and abnormal oxidation contributes to multiple diseases, including cancer. Detecting and quantifying protein oxidation is crucial for a detailed understanding of redox signaling. We developed an Activated Thiol Sepharose (ATS)-based proteomic approach (ATSP) to globally quantify protein oxidation. ATSP can enrich for H2O2-sensitive thiol peptides, which are more likely to contain reactive cysteines involved in redox signaling. We applied our approach to analyze hereditary leiomyomatosis and renal cell carcinoma (HLRCC), a type of kidney cancer that harbors fumarate hydratase (FH)-inactivating mutations and has elevated ROS levels. Multiple proteins were oxidized in FH-deficient cells, including many metabolic proteins, such as the M2 isoform of pyruvate kinase (PKM2). Treatment of HLRCC cells with dimethyl fumarate (DMF) or PKM2 activators alter PKM2 oxidation levels. This newly developed redox proteomics method can globally detect oxidation of reactive cysteines and can be employed to analyze multiple physiological and pathological conditions.

biochemistry↗

bioRxiv2019

Molecular and functional heterogeneity of cancer associated fibroblasts in high-grade serous ovarian cancer

Recent studies indicate that cancer-associated fibroblasts (CAFs) are phenotypically and functionally heterogeneous. However, little is known about CAF subtypes and the roles they play in cancer progression. Here we identify and characterize two CAF subtypes that coexist within high grade serous ovarian cancers: Fibroblast activation protein (FAP)-high (FH) CAFs resemble the classical myofibroblast-type CAF, whereas FAP-low (FL) CAFs possesses a preadipocyte-like molecular signature. Patients with predominantly FH CAFs have significantly worse outcomes than patients with predominantly FL CAFs. FH CAFs contract collagen gels and aggressively promote proliferation, invasion and therapy resistance of cancer cells, whereas FL CAFs do not. Overexpression of the FL-specific transcription factor TCF21 in FH CAFs decreases their ability to promote gel contraction, invasion, and in vivo tumor growth. Understanding CAF subtypes in more detail could lead to better patient stratification and novel therapeutic strategies.

cancer biology↗

bioRxiv2018

Migration rather than proliferation transcriptomic signatures are strongly associated with breast cancer patient survival

The efficacy of prospective cancer treatments is routinely estimated by in vitro cell-line proliferation screens. However, it is unclear whether tumor aggressiveness and patient survival are influenced more by the proliferative or the migratory properties of cancer cells. To address this question, we experimentally measured proliferation and migration phenotypes across more than 40 breast cancer cell-lines. Based on the latter, we built and validated individual predictors of breast cancer proliferation and migration levels from the cells transcriptomics. We then apply these predictors to estimate the proliferation and migration levels of more than 1000 TCGA breast cancer tumors. Reassuringly, both estimates increase with tumors aggressiveness, as qualified by its stage, grade, and subtype. However, predicted tumor migration levels are significantly more strongly associated with patient survival than the proliferation levels. We confirm these finding by conducting siRNA knock-down experiments on the highly migratory MDA-MB-231 cell lines and deriving gene knock-down based proliferation and migration signatures. We show that cytoskeletal drugs might be more beneficial in patients with high predicted migration levels. Taken together, these results testify to the importance of migration levels in determining patient survival.

bioinformatics↗