Biology subjects

Abou-Fadel, J.

Publications and source records attributed to Abou-Fadel, J..

8 recordsLinked to original sources

bioRxiv2023

Whole-genome Omics delineates the function of CCM1 within the CmPn networks

IntroductionCerebral cavernous malformations (CCMs) are abnormal dilations of brain capillaries that increase the risk of hemorrhagic strokes. Mutations in the KRIT1, MGC4607, and PDCD10 genes cause CCMs, with mutations in CCM1 accounting for about 50% of familial cases. The disorder exhibits incomplete penetrance, meaning that individuals with CCM may appear normal initially, but once symptoms manifest, their brains have already suffered irreversible damage. Compromised blood-brain barrier (BBB) is crucial in regulating the flow of substances between the blood and the central nervous system, which can result in hemorrhagic CCMs. Progesterone and its derivatives have been studied for their impact on maintaining BBB integrity. CCM2 interacts with CCM1 and CCM3, forming the CCM signaling complex (CSC), which connects classic and non-classic progesterone signaling to establish the CmPn signaling network, vital in preserving BBB integrity. MethodsThe study aimed to explore the relationship between CCM1 and key pathways of the CmPn signaling network, utilizing a toolset comprising three mouse embryonic fibroblast lines (MEFs) with distinct CCM1 expression levels. Omics and systems biology analysis were performed to investigate Ccm1-mediated signaling within the CmPn signaling network. ResultsThe findings suggest that CCM1 plays a critical role in controlling cellular processes in response to different progesterone-mediated actions within CmPn/CmP signaling networks, partly by regulating gene transcription. This function is crucial for preserving the integrity of microvessels, indicating that targeting CCM1 could hold promise as a therapeutic approach for this condition.

molecular biology↗

bioRxiv2023

Blood prognostic biomarker signatures for hemorrhagic cerebral cavernous malformations (CCMs)

BackgroundCerebral cavernous malformations (CCMs) is a neurological disorder that causes enlarged intracranial capillaries in the brain, leading to an increased risk of hemorrhagic strokes, which is a leading cause of death and disability worldwide. ObjectivesThe current treatment options for CCMs are limited, highlighting the need for prognostic biomarkers to predict the risk of hemorrhagic events to better inform treatment decisions and identify future pharmacological targets. Eligibility CriteriaThe study is centered on a comparative proteomic analysis between hemorrhagic CCMs (HCs) and healthy controls, while excluding patients with non-hemorrhagic CCMs (NHCs) from the analysis due to the experimental design. Sources of EvidenceRecent research has identified several serum biomarkers and blood circulating biomarkers in a selected cohort of homogeneous CCM patients and animal models. MethodProteomic profiles from both human and mouse CCM models were examined, and pathway enrichment analyses were performed using three approaches (GO, KEGG, and DOSE). To account for multiple comparisons, t-tests were employed to evaluate differences. A p-value below 0.05 was deemed statistically significant. ResultsThe authors have developed the first panel of candidate biomarker signatures, featuring both etiological and prognostic markers in two distinct pathways. This panel of biomarker signatures demonstrates a robust correlation with the likelihood of hemorrhagic CCMs. ConclusionsThis groundbreaking biomarker panel paves the way for further investigation of potential blood biomarkers to determine the risk of hemorrhagic CCMs.

genomics↗

bioRxiv2021

In silico Analysis of Nonsynonymous Genomic Variants within CCM2 Gene Reaffirm the Existence of Dual Cores within Typical PTB Domain

PurposeThe objective of this study is to validate the existence of dual cores within the typical phosphotyrosine binding (PTB) domain and to identify potentially damaging and pathogenic nonsynonymous coding single nuclear polymorphisms (nsSNPs) in the canonical PTB domain of the CCM2 gene that causes cerebral cavernous malformations (CCMs). MethodsThe nsSNPs within the coding sequence for PTB domain of human CCM2 gene, retrieved from exclusive database search, were analyzed for their functional and structural impact using a series of bioinformatic tools. The effects of the mutations on tertiary structure of the PTB domain in human CCM2 protein were predicted to examine the effect of the nsSNPs on tertiary structure on PTB Cores. ResultsOur mutation analysis, through alignment of protein structures between wildtype CCM2 and mutant, indicated that the structural impacts of pathogenic nsSNPs is biophysically limited to only the spatially adjacent substituted amino acid site with minimal structural influence on the adjacent core of the PTB domain, suggesting both cores are independently functional and essential for proper CCM2 function. ConclusionUtilizing a combination of protein conservation and structure-based analysis, we analyzed the structural effects of inherited pathogenic mutations within the CCM2 PTB domain. Our results indicated that the pathogenic amino acid substitutions lead to only subtle changes locally confined to the surrounding tertiary structure of the PTB core within which it resides, while no structural disturbance to the neighboring PTB core was observed, reaffirming the presence of dual functional cores in the PTB domain.

biochemistry↗

bioRxiv2021

Disrupting the CmP signaling network unveils novel biomarkers for triple negative breast cancer in Caucasian American women

Triple-negative breast cancer (TNBC) constitutes [~]15 percent of all diagnosed invasive breast cancer cases with limited options for treatment since immunotherapies that target the ER, PR and HER2 receptors are ineffective. Progesterone (PRG) is capable of inducing its effects through either classic, non-classic, or combined responses by binding to classic nuclear PRG receptors (nPRs) or non-classic membrane PRG receptors (mPRs). Under PRG-induced actions, we previously demonstrated that the CSC (CCM signaling complex) can couple both nPRs and mPRs into a CmPn signaling network which plays an important role in nPR(+) breast cancer tumorigeneses. We recently defined the novel CmP signaling network in TNBC cells, which overlapped with our previously defined CmPn network in nPR(+) breast cancer cells. In this study, we were able to demonstrate alterations to key tumorigenesis pathways in Caucasian American Women (CAW)-TNBC cells, under mPRs-specific steroid actions. These results suggest that even though TNBC diagnoses in AAW are associated with more aggressive forms of the disease, and experience a higher mortality rate, TNBC in CAW share similar altered signaling pathways, under mPRs-specific steroid actions, demonstrating the overall aggressive nature of TNBCs, regardless of racial differences. Furthermore, in this report, we have identified 21 new CAW-TNBC specific candidate biomarkers that reinforce the definitive role of the CmP signaling network in TNBC tumorigenesis, initially identified in our previous studies with AAW-TNBCs. This new set of potential prognostic biomarkers may revolutionize molecular mechanisms and currently known concepts of tumorigenesis in CAW-TNBCs, leading to hopeful new therapeutic strategies.

cancer biology↗

bioRxiv2021

CmP signaling network unveils novel biomarkers for triple negative breast cancer in African American women

Breast cancer is the most commonly diagnosed cancer worldwide and remains the second leading cause of cancer death. While breast cancer mortality has steadily declined over the past decades through medical advances, an alarming disparity in breast cancer mortality has emerged between African American women (AAW) and Caucasian American women (CAW); and new evidence suggests more aggressive behavior of triple-negative breast cancer (TNBC) in AAW may contribute to racial differences in tumor biology and mortality. Progesterone (PRG) is capable of exerting its cellular effects through either its classic, non-classic or combined responses through binding to either classic nuclear PRG receptors (nPRs) or non-classic membrane PRG receptors (mPRs), warranting both pathways an equally important status in PRG-mediated signaling. In our previous report, we demonstrated that the CCM signaling complex (CSC) consisting of CCM1, CCM2, and CCM3 proteins can couple both nPRs and mPRs signaling cascades to form a CSC-mPRs-PRG-nPRs (CmPn) signaling network in nPR positive(+) breast cancer cells. In this report, we furthered our research by establishing the CSC-mPRs-PRG (CmP) signaling network in nPR(-) breast cancer cells, demonstrating that a common core mechanism exists, regardless of nPR(+/-) cell type. This is the first report stating that inducible expression patterns exist between CCMs and major mPRs in TNBC cells. Furthermore, we firstly show mPRs in TNBC cells are localized in the nucleus and participate in nucleocytoplasmic shuttling in a coordinately synchronized fashion with CCM proteins under steroid actions, following the same cellular distribution as other well-defined steroid hormone receptors. Finally, for the first time, we deconvoluted the CmP signalosome by using multi-omics approaches, which helped us understand key factors within the CmP network, and identify 21 specific biomarkers with potential clinical applications associated with AAW-TNBC tumorigenesis. These novel biomarkers could have immediate clinical implications to dramatically improve health disparities among AAW-TNBCs.

cancer biology↗

bioRxiv2020

CCM signaling complex (CSC) is a master regulator governing homeostasis of progestins and their mediated signaling cascades

We demonstrate that a novel signaling network among the CSC and mPRS is dynamically modulated and fine-tuned with intricate feedback regulations in PR negative cells, especially endothelial cells (ECs). Depletion of any of three CCMs (1, 2, 3) genes results in the disruption of non-classic mPRs-mediated signaling in-vitro as well as defective homeostasis of PRG in-vivo. Therefore, we propose the CSC is a master regulator of homeostasis of PRG and its associated classic and non-classic signaling cascades. Assisted with omic approaches, we identified signaling pathways involved and specific biomarkers associated with hemorrhagic events during CCM pathogenesis in-vitro and in-vivo. To our knowledge, this is the first report detailing etiology to predict the occurrence of early hemorrhagic events with a set of serum biomarkers.

neuroscience↗

bioRxiv2020

CCM signaling complex (CSC) coupling both classic and non-classic progesterone receptor signaling

Excessive progesterone (PRG) may increase breast cancer risk under hormone therapy during postmenopause or hormonal contraception. As a sex steroid hormone, PRG exerts its cellular responses through signaling cascades involving classic (genomic), non-classic (non-genomic), or both combined responses by binding to either classic nuclear PRG receptors or non-classic membrane PRG receptors. Currently, the intricate balance and switch mechanisms between these two signaling cascades remain elusive. Three genes, KRIT1 (CCM1), MGC4607 (CCM2), and PDCD10 (CCM3), have been demonstrated to form a CCM signaling complex (CSC). In this report, we discover that the CSC plays an essential role in coupling both classic and non-classic PRG signaling pathways by mediating crosstalk between them. The coupled signaling pathways were detailed through high throughput omics. One Sentence SummaryWe discover a novel signaling network among the CCM signaling complex (CSC), classic and non-classic progesterone receptors, and their ligands-progesterone/mifepristone, is dynamically modulated and fine-tuned with a series of feedback regulations; perturbation of this intricate balance, such as hormone therapy in the postmenopause or hormonal contraception regimen, or perturbed CSC signaling could result in increased risks in breast cancer or compromising tumor therapy.

neuroscience↗

bioRxiv2019

Systems-wide analysis unravels the new roles of CCM signal complex (CSC)

Cerebral cavernous malformations (CCMs) are characterized by abnormally dilated intracranial capillaries that result in increased susceptibility to stroke. Three genes have been identified as causes of CCMs; KRIT1 (CCM1), MGC4607 (CCM2) and PDCD10 (CCM3); one of them is disrupted in most CCM cases. It was demonstrated that both CCM1 and CCM3 bind to CCM2 to form a CCM signaling complex (CSC) to modulate angiogenesis. In this report, we deployed both RNA-seq and proteomic analysis of perturbed CSC after depletion of one of three CCM genes to generate interactomes for system-wide studies. Our results demonstrated a unique portrait detailing alterations in angiogenesis and vascular integrity. Interestingly, only in-direct overlapped alterations between RNA and protein levels were detected, supporting the existence of multiple layers of regulation in CSC cascades. Notably, this is the first report identifying that both {beta}4 integrin and CAV1 signaling are downstream of CSC, conveying the angiogenic signaling. Our results provide a global view of signal transduction modulated by the CSC, identifies novel regulatory signaling networks and key cellular factors associated with CSC.

systems biology↗