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2.
Am J Obstet Gynecol ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38723985

ABSTRACT

BACKGROUND: Black women are at an increased risk of developing uterine leiomyomas and experiencing worse disease prognosis than White women. Epidemiologic and molecular factors have been identified as underlying these disparities, but there remains a paucity of deep, multiomic analysis investigating molecular differences in uterine leiomyomas from Black and White patients. OBJECTIVE: To identify molecular alterations within uterine leiomyoma tissues correlating with patient race by multiomic analyses of uterine leiomyomas collected from cohorts of Black and White women. STUDY DESIGN: We performed multiomic analysis of uterine leiomyomas from Black (42) and White (47) women undergoing hysterectomy for symptomatic uterine leiomyomata. In addition, our analysis included the application of orthogonal methods to evaluate fibroid biomechanical properties, such as second harmonic generation microscopy, uniaxial compression testing, and shear-wave ultrasonography analyses. RESULTS: We found a greater proportion of MED12 mutant uterine leiomyomas from Black women (>35% increase; Mann-Whitney U, P<.001). MED12 mutant tumors exhibited an elevated abundance of extracellular matrix proteins, including several collagen isoforms, involved in the regulation of the core matrisome. Histologic analysis of tissue fibrosis using trichrome staining and secondary harmonic generation microscopy confirmed that MED12 mutant tumors are more fibrotic than MED12 wild-type tumors. Using shear-wave ultrasonography in a prospectively collected cohort, Black patients had fibroids that were firmer than White patients, even when similar in size. In addition, these analyses uncovered ancestry-linked expression quantitative trait loci with altered allele frequencies in African and European populations correlating with differential abundance of several proteins in uterine leiomyomas independently of MED12 mutation status, including tetracoidpeptide repeat protein 38. CONCLUSION: Our study shows that Black women have a higher prevalence of uterine leiomyomas harboring mutations in MED12 and that this mutational status correlates with increased tissue fibrosis compared with wild-type uterine leiomyomas. Our study provides insights into molecular alterations correlating with racial disparities in uterine leiomyomas and improves our understanding of the molecular etiology underlying uterine leiomyoma development within these populations.

3.
NPJ Precis Oncol ; 8(1): 68, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38480868

ABSTRACT

We performed a deep proteogenomic analysis of bulk tumor and laser microdissection enriched tumor cell populations from high-grade serous ovarian cancer (HGSOC) tissue specimens spanning a broad spectrum of purity. We identified patients with longer progression-free survival had increased immune-related signatures and validated proteins correlating with tumor-infiltrating lymphocytes in 65 tumors from an independent cohort of HGSOC patients, as well as with overall survival in an additional 126 HGSOC patient cohort. We identified that homologous recombination deficient (HRD) tumors are enriched in pathways associated with metabolism and oxidative phosphorylation that we validated in independent patient cohorts. We further identified that polycomb complex protein BMI-1 is elevated in HR proficient (HRP) tumors, that elevated BMI-1 correlates with poor overall survival in HRP but not HRD HGSOC patients, and that HRP HGSOC cells are uniquely sensitive to BMI-1 inhibition.

4.
iScience ; 27(3): 109198, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38439970

ABSTRACT

Numerous multi-omic investigations of cancer tissue have documented varying and poor pairwise transcript:protein quantitative correlations, and most deconvolution tools aiming to predict cell type proportions (cell admixture) have been developed and credentialed using transcript-level data alone. To estimate cell admixture using protein abundance data, we analyzed proteome and transcriptome data generated from contrived admixtures of tumor, stroma, and immune cell models or those selectively harvested from the tissue microenvironment by laser microdissection from high grade serous ovarian cancer (HGSOC) tumors. Co-quantified transcripts and proteins performed similarly to estimate stroma and immune cell admixture (r ≥ 0.63) in two commonly used deconvolution algorithms, ESTIMATE or ConsensusTME. We further developed and optimized protein-based signatures estimating cell admixture proportions and benchmarked these using bulk tumor proteomic data from over 150 patients with HGSOC. The optimized protein signatures supporting cell type proportion estimates from bulk tissue proteomic data are available at https://lmdomics.org/ProteoMixture/.

5.
Clin Proteomics ; 21(1): 4, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38254014

ABSTRACT

BACKGROUND: Although uterine serous carcinoma (USC) represents a small proportion of all uterine cancer cases, patients with this aggressive subtype typically have high rates of chemotherapy resistance and disease recurrence that collectively result in a disproportionately high death rate. The goal of this study was to provide a deeper view of the tumor microenvironment of this poorly characterized uterine cancer variant through multi-region microsampling and quantitative proteomics. METHODS: Tumor epithelium, tumor-involved stroma, and whole "bulk" tissue were harvested by laser microdissection (LMD) from spatially resolved levels from nine USC patient tumor specimens and underwent proteomic analysis by mass spectrometry and reverse phase protein arrays, as well as transcriptomic analysis by RNA-sequencing for one patient's tumor. RESULTS: LMD enriched cell subpopulations demonstrated varying degrees of relatedness, indicating substantial intratumor heterogeneity emphasizing the necessity for enrichment of cellular subpopulations prior to molecular analysis. Known prognostic biomarkers were quantified with stable levels in both LMD enriched tumor and stroma, which were shown to be highly variable in bulk tissue. These USC data were further used in a comparative analysis with a data generated from another serous gynecologic malignancy, high grade serous ovarian carcinoma, and have been added to our publicly available data analysis tool, the Heterogeneity Analysis Portal ( https://lmdomics.org/ ). CONCLUSIONS: Here we identified extensive three-dimensional heterogeneity within the USC tumor microenvironment, with disease-relevant biomarkers present in both the tumor and the stroma. These data underscore the critical need for upfront enrichment of cellular subpopulations from tissue specimens for spatial proteogenomic analysis.

6.
Clin Exp Metastasis ; 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-37917186

ABSTRACT

Breast cancer in young patients is known to exhibit more aggressive biological behavior and is associated with a less favorable prognosis than the same disease in older patients, owing in part to an increased incidence of brain metastases. The mechanistic explanations behind these findings remain poorly understood. We recently reported that young mice, in comparison to older mice, developed significantly greater brain metastases in four mouse models of triple-negative and luminal B breast cancer. Here we have performed a quantitative mass spectrometry-based proteomic analysis to identify proteins potentially contributing to age-related disparities in the development of breast cancer brain metastases. Using a mouse hematogenous model of brain-tropic triple-negative breast cancer (MDA-MB-231BR), we harvested subpopulations of tumor metastases, the tumor-adjacent metastatic microenvironment, and uninvolved brain tissues via laser microdissection followed by quantitative proteomic analysis using high resolution mass spectrometry to characterize differentially abundant proteins potentially contributing to age-dependent rates of brain metastasis. Pathway analysis revealed significant alterations in signaling pathways, particularly in the metastatic microenvironment, modulating tumorigenesis, metabolic processes, inflammation, and neuronal signaling. Tenascin C (TNC) was significantly elevated in all laser microdissection (LMD) enriched compartments harvested from young mice relative to older hosts, which was validated and confirmed by immunoblot analysis of whole brain lysates. Additional in vitro studies including migration and wound-healing assays demonstrated TNC as a positive regulator of tumor cell migration. These results provide important new insights regarding microenvironmental factors, including TNC, as mechanisms contributing to the increased brain cancer metastatic phenotype observed in young breast cancer patients.

7.
Transl Psychiatry ; 13(1): 318, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37833300

ABSTRACT

Alcohol use disorder (AUD) affects transcriptomic, epigenetic and proteomic expression in several organs, including the brain. There has not been a comprehensive analysis of altered protein abundance focusing on the multiple brain regions that undergo neuroadaptations occurring in AUD. We performed a quantitative proteomic analysis using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of human postmortem tissue from brain regions that play key roles in the development and maintenance of AUD, the amygdala (AMG), hippocampus (HIPP), hypothalamus (HYP), nucleus accumbens (NAc), prefrontal cortex (PFC) and ventral tegmental area (VTA). Brain tissues were from adult males with AUD (n = 11) and matched controls (n = 16). Across the two groups, there were >6000 proteins quantified with differential protein abundance in AUD compared to controls in each of the six brain regions. The region with the greatest number of differentially expressed proteins was the AMG, followed by the HYP. Pathways associated with differentially expressed proteins between groups (fold change > 1.5 and LIMMA p < 0.01) were analyzed by Ingenuity Pathway Analysis (IPA). In the AMG, adrenergic, opioid, oxytocin, GABA receptor and cytokine pathways were among the most enriched. In the HYP, dopaminergic signaling pathways were the most enriched. Proteins with differential abundance in AUD highlight potential therapeutic targets such as oxytocin, CSNK1D (PF-670462), GABAB receptor and opioid receptors and may lead to the identification of other potential targets. These results improve our understanding of the molecular alterations of AUD across brain regions that are associated with the development and maintenance of AUD. Proteomic data from this study is publicly available at www.lmdomics.org/AUDBrainProteomeAtlas/ .


Subject(s)
Alcoholism , Male , Adult , Humans , Alcoholism/metabolism , Oxytocin , Proteomics , Chromatography, Liquid , Tandem Mass Spectrometry , Brain/metabolism , Proteins
8.
Cancers (Basel) ; 14(17)2022 Aug 23.
Article in English | MEDLINE | ID: mdl-36077609

ABSTRACT

Objectives: A risk assessment model for metastasis in endometrioid endometrial cancer (EEC) was developed using molecular and clinical features, and prognostic association was examined. Methods: Patients had stage I, IIIC, or IV EEC with tumor-derived RNA-sequencing or microarray-based data. Metastasis-associated transcripts and platform-centric diagnostic algorithms were selected and evaluated using regression modeling and receiver operating characteristic curves. Results: Seven metastasis-associated transcripts were selected from analysis in the training cohorts using 10-fold cross validation and incorporated into an MS7 classifier using platform-specific coefficients. The predictive accuracy of the MS7 classifier in Training-1 was superior to that of other clinical and molecular features, with an area under the curve (95% confidence interval) of 0.89 (0.80-0.98) for MS7 compared with 0.69 (0.59-0.80) and 0.71 (0.58-0.83) for the top evaluated clinical and molecular features, respectively. The performance of MS7 was independently validated in 245 patients using RNA sequencing and in 81 patients using microarray-based data. MS7 + MI (myometrial invasion) was preferrable to individual features and exhibited 100% sensitivity and negative predictive value. The MS7 classifier was associated with lower progression-free and overall survival (p ≤ 0.003). Conclusion: A risk assessment classifier for metastasis and prognosis in EEC patients with primary tumor derived MS7 + MI is available for further development and optimization as a companion clinical support tool.

9.
iScience ; 24(7): 102757, 2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34278265

ABSTRACT

Enriched tumor epithelium, tumor-associated stroma, and whole tissue were collected by laser microdissection from thin sections across spatially separated levels of ten high-grade serous ovarian carcinomas (HGSOCs) and analyzed by mass spectrometry, reverse phase protein arrays, and RNA sequencing. Unsupervised analyses of protein abundance data revealed independent clustering of an enriched stroma and enriched tumor epithelium, with whole tumor tissue clustering driven by overall tumor "purity." Comparing these data to previously defined prognostic HGSOC molecular subtypes revealed protein and transcript expression from tumor epithelium correlated with the differentiated subtype, whereas stromal proteins (and transcripts) correlated with the mesenchymal subtype. Protein and transcript abundance in the tumor epithelium and stroma exhibited decreased correlation in samples collected just hundreds of microns apart. These data reveal substantial tumor microenvironment protein heterogeneity that directly bears on prognostic signatures, biomarker discovery, and cancer pathophysiology and underscore the need to enrich cellular subpopulations for expression profiling.

10.
Sci Rep ; 11(1): 9371, 2021 04 30.
Article in English | MEDLINE | ID: mdl-33931688

ABSTRACT

Pathogenic mutations in fumarate hydratase (FH) drive hereditary leiomyomatosis and renal cell cancer (HLRCC) and increase the risk of developing uterine leiomyomas (ULMs). An integrated proteogenomic analysis of ULMs from HLRCC (n = 16; FH-mutation confirmed) and non-syndromic (NS) patients (n = 12) identified a significantly higher protein:transcript correlation in HLRCC (R = 0.35) vs. NS ULMs (R = 0.242, MWU p = 0.0015). Co-altered proteins and transcripts (228) included antioxidant response element (ARE) target genes, such as thioredoxin reductase 1 (TXNRD1), and correlated with activation of NRF2-mediated oxidative stress response signaling in HLRCC ULMs. We confirm 185 transcripts previously described as altered between HLRCC and NS ULMs, 51 co-altered at the protein level and several elevated in HLRCC ULMs are involved in regulating cellular metabolism and glycolysis signaling. Furthermore, 367 S-(2-succino)cysteine peptides were identified in HLRCC ULMs, of which sixty were significantly elevated in HLRCC vs. NS ULMs (LogFC = 1.86, MWU p < 0.0001). These results confirm and define novel proteogenomic alterations in uterine leiomyoma tissues collected from HLRCC patients and underscore conserved molecular alterations correlating with inactivation of the FH tumor suppressor gene.


Subject(s)
Biomarkers, Tumor/analysis , Fumarate Hydratase/genetics , Genetic Predisposition to Disease , Leiomyomatosis/pathology , Mutation , Neoplastic Syndromes, Hereditary/pathology , Proteogenomics/methods , Proteome/metabolism , Skin Neoplasms/pathology , Uterine Neoplasms/pathology , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Case-Control Studies , Female , Humans , Leiomyomatosis/metabolism , Neoplastic Syndromes, Hereditary/metabolism , Proteome/analysis , Skin Neoplasms/metabolism , Uterine Neoplasms/metabolism
11.
Clin Proteomics ; 17: 9, 2020.
Article in English | MEDLINE | ID: mdl-32165870

ABSTRACT

Reversible protein phosphorylation represents a key mechanism by which signals are transduced in eukaryotic cells. Dysregulated phosphorylation is also a hallmark of carcinogenesis and represents key drug targets in the precision medicine space. Thus, methods that preserve phosphoprotein integrity in the context of clinical tissue analyses are crucially important in cancer research. Here we investigated the impact of UV laser microdissection (UV LMD) and IR laser capture microdissection (IR LCM) on phosphoprotein abundance of key cancer signaling protein targets assessed by reverse-phase protein microarray (RPPA). Tumor epithelial cells from consecutive thin sections obtained from four high-grade serous ovarian cancers were harvested using either UV LMD or IR LCM methods. Phosphoprotein abundances for ten phosphoproteins that represent important drug targets were assessed by RPPA and revealed no significant differences in phosphoprotein integrity from those obtained using higher-energy UV versus the lower-energy IR laser methods.

12.
Cancer Med ; 9(3): 1092-1103, 2020 02.
Article in English | MEDLINE | ID: mdl-31808620

ABSTRACT

Preoperative use of metformin in obese women with endometrioid endometrial cancer (EEC) reduces tumor proliferation and inhibits the mammalian target of rapamycin pathway, though is only effective in select cases. This study sought to identify a predictive and/or pharmacodynamic proteomic signature of metformin response to tailor its pharmacologic use. Matched pre- and post-metformin-treated tumor tissues from a recently completed preoperative window trial of metformin in EEC patients (ClinicalTrials.gov: NCT01911247) were analyzed by mass spectrometry (MS)-based proteomic and immunohistochemical analyses. Jupiter microtubule-associated homolog 1 (JPT1) was significantly elevated in metformin responders (n = 13) vs nonresponders (n = 7), and found to decrease in abundance in metformin responders following treatment; observations that were verified by immunohistochemical staining for JPT1. Metformin response and loss of JPT1 were assessed in RL95-2 and ACI-181 endometrial cancer (EC) cell lines. We further identified that silencing of JPT1 abundance does not alter cellular response to metformin or basal cell proliferation, but that JPT1 abundance does decrease in response to metformin treatment in RL95-2 and ACI-181 EC cell lines. These data suggest that JPT1 represents a predictive and pharmacodynamic biomarker of metformin response that, if validated in larger patient populations, may enable preoperative EEC patient stratification to metformin treatment and the ability to monitor patient response.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Endometrioid/therapy , Cell Cycle Proteins/metabolism , Endometrial Neoplasms/therapy , Metformin/pharmacology , Microtubule-Associated Proteins/metabolism , Obesity/complications , Adolescent , Adult , Aged , Carcinoma, Endometrioid/complications , Carcinoma, Endometrioid/metabolism , Carcinoma, Endometrioid/pathology , Cell Cycle Proteins/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Chemotherapy, Adjuvant/methods , Clinical Trials, Phase I as Topic , Drug Resistance, Neoplasm , Endometrial Neoplasms/complications , Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , Endometrium/pathology , Endometrium/surgery , Female , Gene Knockdown Techniques , Humans , Hysterectomy , Metformin/therapeutic use , Microtubule-Associated Proteins/genetics , Middle Aged , Neoadjuvant Therapy/methods , Obesity/metabolism , Proteomics , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism , Young Adult
13.
Cancer ; 123(20): 4004-4012, 2017 Oct 15.
Article in English | MEDLINE | ID: mdl-28654152

ABSTRACT

BACKGROUND: The objective of this study was to identify molecular alterations associated with disease outcomes for white and black patients with endometrioid endometrial cancer (EEC). METHODS: EEC samples from black (n = 17) and white patients (n = 13) were analyzed by proteomics (liquid chromatography-tandem mass spectrometry) and transcriptomics (RNA-seq). Coordinate alterations were validated with RNA-seq data from black (n = 49) and white patients (n = 216). Concordantly altered candidates were further tested for associations with race-specific progression-free survival (PFS) in black (n = 64) or white patients (n = 267) via univariate and multivariate Cox regression modeling and log-rank testing. RESULTS: Discovery analyses revealed significantly altered candidate proteins and transcripts between black and white patients, suggesting modulation of tumor cell viability in black patients and cell death signaling in black and white patients. Eighty-nine candidates were validated as altered between these patient cohorts, and a subset significantly correlated with differential PFS. White-specific PFS candidates included serpin family A member 4 (SERPINA4; hazard ratio [HR], 0.89; Wald P value = .02), integrin subunit α3 (ITGA3; HR, 0.76; P = .03), and Bet1 Golgi vesicular membrane trafficking protein like (BET1L; HR, 0.48; P = .04). Black-specific PFS candidates included family with sequence similarity 228 member B (FAM228B; HR, 0.13; P = .001) and HEAT repeat containing 6 (HEATR6; HR, 4.94; P = .047). Several candidates were also associated with overall survival (SERPINA4 and ITGA3) as well as PFS independent of disease stage, grade and myometrial invasion (SERPINA4, BET1L and FAM228B). CONCLUSIONS: This study has identified and validated molecular alterations in tumors from black and white EEC patients, including candidates significantly associated with altered disease outcomes within these patient cohorts. Cancer 2017;123:4004-12. © 2017 American Cancer Society.


Subject(s)
Carcinoma, Endometrioid/genetics , Endometrial Neoplasms/genetics , Black or African American , Carcinoma, Endometrioid/ethnology , Carcinoma, Endometrioid/metabolism , Carcinoma, Endometrioid/pathology , Chromatography, Liquid , Disease-Free Survival , Endometrial Neoplasms/ethnology , Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , Female , Gene Expression Profiling , Health Status Disparities , Humans , Integrin alpha3 , Membrane Proteins/genetics , Membrane Proteins/metabolism , Multivariate Analysis , Neoplasm Grading , Neoplasm Staging , Prognosis , Proportional Hazards Models , Qc-SNARE Proteins , Serpins , Tandem Mass Spectrometry , White People
14.
Front Oncol ; 6: 213, 2016.
Article in English | MEDLINE | ID: mdl-27833898

ABSTRACT

BACKGROUND AND OBJECTIVE: Nua kinase 1 (NUAK1) was identified in multigene signatures of survival and suboptimal debulking in high-grade serous ovarian cancer (HGSOC). This study investigates the individual clinical and biologic contributions of NUAK1 in HGSOC patients and cell lines. METHODS: Public transcript expression, clinical, and outcome data were used to interrogate the relationship between NUAK1 and clinicopathologic factors and patient outcomes including progression-free survival (PFS) and molecular subtypes using logistic and Cox modeling. Analysis of NUAK1 transcript expression was performed in primary tumors from 34 HGSOC patients with < or ≥2 years PFS. The impact of silencing NUAK1 by RNA interference (RNAi) on the migratory potential and chemosensitivity of SOC cells was assessed in vitro. RESULTS: Elevated NUAK1 transcript expression was associated with worse PFS (hazard ratio = 1.134), advanced stage (odds ratio, OR = 1.7), any residual disease (OR = 1.58), and mesenchymal disease subtype (OR = 7.79 ± 5.89). Elevated NUAK1 transcript expression was observed in HGSOC patients with < vs. ≥2 years PFS (p < 0.045). RNAi-mediated silencing of NUAK1 expression attenuated migration of OV90 and E3 HGSOC cells in vitro, but did not modulate sensitivity to cisplatin or paclitaxel. CONCLUSION: Elevated NUAK1 was associated with poor survival as well as advanced stage, residual disease after cytoreductive surgery and mesenchymal molecular subtype. NUAK1 impacted migration, but not chemosensitivity, in vitro. Additional studies are needed to further develop the concept of NUAK1 as a clinically deployable biomarker and therapeutic target in HGSOC.

15.
Biochem J ; 473(21): 3819-3836, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27623775

ABSTRACT

Rhodopsin is a prototypical G-protein-coupled receptor (GPCR) that initiates phototransduction in the retina. The receptor consists of the apoprotein opsin covalently linked to the inverse agonist 11-cis retinal. Rhodopsin and opsin have been shown to form oligomers within the outer segment disc membranes of rod photoreceptor cells. However, the physiological relevance of the observed oligomers has been questioned since observations were made on samples prepared from the retina at low temperatures. To investigate the oligomeric status of opsin in live cells at body temperatures, we utilized a novel approach called Förster resonance energy transfer spectrometry, which previously has allowed the determination of the stoichiometry and geometry (i.e. quaternary structure) of various GPCRs. In the current study, we have extended the method to additionally determine whether or not a mixture of oligomeric forms of opsin exists and in what proportion. The application of this improved method revealed that opsin expressed in live Chinese hamster ovary (CHO) cells at 37°C exists as oligomers of various sizes. At lower concentrations, opsin existed in an equilibrium of dimers and tetramers. The tetramers were in the shape of a near-rhombus. At higher concentrations of the receptor, higher-order oligomers began to form. Thus, a mixture of different oligomeric forms of opsin is present in the membrane of live CHO cells and oligomerization occurs in a concentration-dependent manner. The general principles underlying the concentration-dependent oligomerization of opsin may be universal and apply to other GPCRs as well.


Subject(s)
Fluorescence Resonance Energy Transfer/methods , Opsins/chemistry , Animals , CHO Cells , Cricetinae , Cricetulus , Opsins/metabolism , Protein Multimerization , Protein Structure, Quaternary , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/metabolism
16.
Biophys J ; 108(7): 1613-1622, 2015 Apr 07.
Article in English | MEDLINE | ID: mdl-25863053

ABSTRACT

Förster resonance energy transfer (FRET) is a nonradiative process for the transfer of energy from an optically excited donor molecule (D) to an acceptor molecule (A) in the ground state. The underlying theory predicting the dependence of the FRET efficiency on the sixth power of the distance between D and A has stood the test of time. In contrast, a comprehensive kinetic-based theory developed recently for FRET efficiencies among multiple donors and acceptors in multimeric arrays has waited for further testing. That theory has been tested in the work described in this article using linked fluorescent proteins located in the cytoplasm and at the plasma membrane of living cells. The cytoplasmic constructs were fused combinations of Cerulean as donor (D), Venus as acceptor (A), and a photo-insensitive molecule (Amber) as a nonfluorescent (N) place holder: namely, NDAN, NDNA, and ADNN duplexes, and the fully fluorescent quadruplex ADAA. The membrane-bound constructs were fused combinations of GFP2 as donor (D) and eYFP as acceptor (A): namely, two fluorescent duplexes (i.e., DA and AD) and a fluorescent triplex (ADA). According to the theory, the FRET efficiency of a multiplex such as ADAA or ADA can be predicted from that of analogs containing a single acceptor (e.g., NDAN, NDNA, and ADNN, or DA and AD, respectively). Relatively small but statistically significant differences were observed between the measured and predicted FRET efficiencies of the two multiplexes. While elucidation of the cause of this mismatch could be a worthy endeavor, the discrepancy does not appear to question the theoretical underpinnings of a large family of FRET-based methods for determining the stoichiometry and quaternary structure of complexes of macromolecules in living cells.


Subject(s)
Fluorescence Resonance Energy Transfer , Green Fluorescent Proteins/metabolism , Models, Chemical , Animals , CHO Cells , Cricetinae , Cricetulus , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/genetics , Kinetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
17.
Biol Reprod ; 92(4): 106, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25695723

ABSTRACT

Despite its importance in reproductive biology and women's health, a detailed molecular-level understanding of the human endometrium is lacking. Indeed, no comprehensive studies have been undertaken to elucidate the important protein expression differences between the endometrial glandular epithelium and surrounding stroma during the proliferative and midsecretory phases of the menstrual cycle. We utilized laser microdissection to harvest epithelial cells and stromal compartments from proliferative and secretory premenopausal endometrial tissue and performed a global, quantitative mass spectrometry-based proteomics analysis. This analysis identified 1224 total proteins from epithelial cells, among which 318 were differentially abundant between the proliferative and secretory phases (q < 0.05), and 1005 proteins from the stromal compartments, 19 of which were differentially abundant between the phases (q < 0.05). Several proteins were chosen for validation by immunohistochemistry in an independent set of uterine tissues, including carboxypeptidase M, tenascin C, neprilysin, and ectonucleotide pyrophosphatase/phosphodiesterase family member 3 (ENPP3). ENPP3, which was elevated in epithelial glandular cells in the secretory phase, was confirmed to be elevated in midsecretory-phase baboon uterine lavage samples and also observed to have an N-linked glycosylated form that was not observed in the proliferative phase. This study provides a detailed view into the global proteomic alterations of the epithelial cells and stromal compartments of the cycling premenopausal endometrium. These proteomic alterations during endometrial remodeling provide a basis for numerous follow-up investigations on the function of these differentially regulated proteins and their role in reproductive biology and endometrial pathologies.


Subject(s)
Endometrium/cytology , Epithelial Cells/metabolism , Follicular Phase/physiology , Luteal Phase/physiology , Proteomics/methods , Stromal Cells/metabolism , Animals , Chromatography, Liquid , Female , Humans , Immunohistochemistry , Microdissection , Papio , Phosphoric Diester Hydrolases/metabolism , Pyrophosphatases/metabolism , Tandem Mass Spectrometry , Uterus/cytology
18.
Biochem J ; 466(2): 263-271, 2015 Mar 01.
Article in English | MEDLINE | ID: mdl-25510962

ABSTRACT

The sigma-1 receptor (S1R) is a 223-amino-acid membrane protein that resides in the endoplasmic reticulum and the plasma membrane of some mammalian cells. The S1R is regulated by various synthetic molecules including (+)-pentazocine, cocaine and haloperidol and endogenous molecules such as sphingosine, dimethyltryptamine and dehydroepiandrosterone. Ligand-regulated protein chaperone functions linked to oxidative stress and neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) and neuropathic pain have been attributed to the S1R. Several client proteins that interact with S1R have been identified including various types of ion channels and G-protein coupled receptors (GPCRs). When S1R constructs containing C-terminal monomeric GFP2 and YFP fusions were co-expressed in COS-7 cells and subjected to FRET spectrometry analysis, monomers, dimers and higher oligomeric forms of S1R were identified under non-liganded conditions. In the presence of the prototypic S1R agonist, (+)-pentazocine, however, monomers and dimers were the prevailing forms of S1R. The prototypic antagonist, haloperidol, on the other hand, favoured higher order S1R oligomers. These data, in sum, indicate that heterologously expressed S1Rs occur in vivo in COS-7 cells in multiple oligomeric forms and that S1R ligands alter these oligomeric structures. We suggest that the S1R oligomerization states may regulate its function(s).


Subject(s)
Cell Membrane/metabolism , Endoplasmic Reticulum/metabolism , Models, Molecular , Receptors, sigma/chemistry , Amino Acid Substitution , Analgesics, Opioid/chemistry , Analgesics, Opioid/pharmacology , Animals , COS Cells , Cell Membrane/drug effects , Chlorocebus aethiops , Dimerization , Endoplasmic Reticulum/drug effects , Haloperidol/chemistry , Haloperidol/pharmacology , Humans , Ligands , Luminescent Proteins/chemistry , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Narcotic Antagonists/chemistry , Narcotic Antagonists/pharmacology , Pentazocine/chemistry , Pentazocine/pharmacology , Point Mutation , Protein Aggregates/drug effects , Protein Stability/drug effects , Receptors, sigma/agonists , Receptors, sigma/genetics , Receptors, sigma/metabolism , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sigma-1 Receptor
19.
Front Oncol ; 3: 139, 2013.
Article in English | MEDLINE | ID: mdl-23785665

ABSTRACT

Endometrial cancer is the most common gynecologic malignancy in the United States but it remains poorly understood at the molecular level. This investigation was conducted to specifically assess whether gene expression changes underlie the clinical and pathologic factors traditionally used for determining treatment regimens in women with stage I endometrial cancer. These include the effect of tumor grade, depth of myometrial invasion and histotype. We utilized oligonucleotide microarrays to assess the transcript expression profile in epithelial glandular cells laser microdissected from 79 endometrioid and 12 serous stage I endometrial cancers with a heterogeneous distribution of grade and depth of myometrial invasion, along with 12 normal post-menopausal endometrial samples. Unsupervised multidimensional scaling analyses revealed that serous and endometrioid stage I cancers have similar transcript expression patterns when compared to normal controls where 900 transcripts were identified to be differentially expressed by at least fourfold (univariate t-test, p < 0.001) between the cancers and normal endometrium. This analysis also identified transcript expression differences between serous and endometrioid cancers and tumor grade, but no apparent differences were identified as a function of depth of myometrial invasion. Four genes were validated by quantitative PCR on an independent set of cancer and normal endometrium samples. These findings indicate that unique gene expression profiles are associated with histologic type and grade, but not myometrial invasion among early stage endometrial cancers. These data provide a comprehensive perspective on the molecular alterations associated with stage I endometrial cancer, particularly those subtypes that have the worst prognosis.

20.
Microsc Microanal ; 19(4): 821-34, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23745591

ABSTRACT

Nanoparticles composed of a magnetic iron oxide core surrounded by a metal shell have utility in a broad range of biomedical applications. However, the presence of surface energy differences between the two components makes wetting of oxide with metal unfavorable, precluding a "core-shell" structure of an oxide core completely surrounded by a thin metal shell. Three-dimensional island growth followed by island coalescence into thick shells is favored over the two-dimensional layer-by-layer growth of a thin, continuous metal coating of a true core-shell. Aqueous synthesis of gold-coated magnetite nanoparticles with analysis by infrared, energy-dispersive X-ray, and electron energy loss spectroscopies; high-resolution transmission electron microscopy; selected area electron diffraction; and high-angle annular dark-field scanning transmission electron microscopy showed two distinct morphologies that are inconsistent with an idealized core-shell. The majority were isolated ~16-22-nm-diameter nanoparticles consisting of ~7-nm-diameter magnetite and a thick deposition of gold, most often discontinuous, with some potentially "sandwiched" morphologies. A minority were aggregates of agglomerated magnetite decorated with gold but displaying significant bare magnetite. Both populations were successfully conjugated to fibrinogen and targeted to surface-activated platelets, demonstrating that iron oxide-gold nanoparticles produced by aqueous synthesis do not require an ideal core-shell structure for biological activity in cell labeling and targeting applications.


Subject(s)
Blood Platelets/metabolism , Ferrosoferric Oxide/metabolism , Fibrinogen/metabolism , Gold/metabolism , Nanoparticles/metabolism , Ferrosoferric Oxide/chemistry , Fibrinogen/chemistry , Gold/chemistry , Humans , Nanoparticles/chemistry , Protein Binding
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