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Tobacco abuse is a major risk factor associated with the development of oral squamous cell carcinoma. Differences in molecular aberrations induced by tobacco exposure by chewing or smoking form are not well studied in case of oral cancer. We used tandem mass tag-based quantitative proteomic approach to delineate proteomic alterations in oral cancer patients based on their history of tobacco using habits (patients who chewed tobacco, patients who smoked tobacco, and those with no history of tobacco consumption). Our data identified distinct dysregulation of biological processes and pathways in each patient cohort. Bioinformatics analysis of dysregulated proteins identified in our proteomic study revealed dysregulation of collagen formation and antigen processing/presentation pathway in oral cancer patients who smoked tobacco, whereas proteins associated with the process of keratinization showed enrichment in patients who chewed tobacco. In addition, we identified overexpression of proteins involved in immune pathways and downregulation of muscle contraction-mediated signaling events in all three cohorts, irrespective of tobacco using habits. This study lays the groundwork for identification of protein markers that may aid in identification of high-risk patients for cancer development based on the history of tobacco exposure habits. [ABSTRACT FROM AUTHOR]

Epidermal growth factor (EGF) plays an important role in metastasis and tumorigenesis of prostate cancer. Epithelial–mesenchymal transition (EMT) is a process in tumor progression during which cancer cells undergo dramatic changes acquiring highly invasive properties. The purpose of this study was to determine the effect of quercetin on EGF-induced EMT in prostate cancer (PC-3) cell line. Quercetin, a plant flavonoid, prevented EGF-induced invasion and migration of PC-3 cells. The protein and mRNA expressions of E-cadherin and N-cadherin were studied by immunocytochemistry, Western blotting and real-time polymerase chain reaction. Quercetin prevented EGF-induced expression of N-cadherin and vimentin and increased the expression of E-cadherin in PC-3 cells, therefore preventing EGF-induced EMT. EGF-induced cell adhesion proteins, intercellular adhesion molecule and vascular cell adhesion molecule were significantly decreased by quercetin treatment. Furthermore, mRNA and protein expressions of Snail, Slug and Twist showed that quercetin significantly decreased EGF-induced expressions of Snail, Slug and Twist. The protein expressions of epidermal growth factor receptor (EGFR)/phosphatidylinositide 3-kinases (PI3K)/Akt/extracellular signal-regulated kinase (ERK)1/2 pathway showed that quercetin prevents EGF-induced EMT via EGFR/PI3k/Akt/ERK1/2 pathway and by suppressing transcriptional repressors Snail, Slug and Twist in PC-3 cells. Thus, it is concluded from the present study that quercetin may prevent cancer metastasis by targeting EMT. [ABSTRACT FROM AUTHOR]

Abstract: Di-2-ethyl hexyl phthalate (DEHP), an industrial plasticizer and a ubiquitous environmental contaminant, is an established endocrine disruptor (ED). Increasing evidences indicate that some EDs interfere with osteoblast differentiation and function. In the present study, we investigated the effects of DEHP on the expression of cell cycle proteins, differentiation markers, Runx2 and its co-activator TAZ in osteoblasts derived from neonatal rat calvaria. A significant decrease in protein levels of cyclin D1 and CDK-2 was found at high dosage of DEHP (100μM) after 24h treatment. DEHP treatment caused a significant decrease in ALP mRNA. While DEHP treatment significantly decreased the TAZ at mRNA and protein levels, it decreased only the Runx2protein levels. Histochemical localization of ALP, collagen and mineralized nodules studied from cells treated with DEHP (10 and 100μM) for 21days revealed a drastic decrease in collagen, ALP and mineralization. In conclusion, DEHP affected differentiation of neonatal rat calvarial osteoblasts and mineralization of matrix secreted by these cells. [Copyright &y& Elsevier]

Selective neuronal vulnerability (SNV) of specific neuroanatomical regions such as frontal cortex (FC) and hippocampus (HC) is characteristic of age-associated neurodegenerative diseases (NDDs), although its pathogenetic basis remains unresolved. We hypothesized that physiological differences in mitochondrial function in neuroanatomical regions could contribute to SNV. To investigate this, we evaluated mitochondrial function in human brains (age range:1–90 y) in FC, striatum (ST), HC, cerebellum (CB) and medulla oblongata (MD), using enzyme assays and quantitative proteomics. Striking differences were noted in resistant regions- MD and CB compared to the vulnerable regions- FC, HC and ST. At younger age (25 ± 5 y), higher activity of electron transport chain enzymes and upregulation of metabolic and antioxidant proteins were noted in MD compared to FC and HC, that was sustained with increasing age (≥65 y). In contrast, the expression of synaptic proteins was higher in FC, HC and ST (vs. MD). In line with this, quantitative phospho-proteomics revealed activation of upstream regulators (ERS, PPARα) of mitochondrial metabolism and inhibition of synaptic pathways in MD. Microtubule Associated Protein Tau (MAPT) showed overexpression in FC, HC and ST both in young and older age (vs. MD). MAPT hyperphosphorylation and the activation of its kinases were noted in FC and HC with age. Our study demonstrates that regional heterogeneity in mitochondrial and other cellular functions contribute to SNV and protect regions such as MD, while rendering FC and HC vulnerable to NDDs. The findings also support the "last in, first out" hypothesis of ageing, wherein regions such as FC , that are the most recent to develop phylogenetically and ontogenetically, are the first to be affected in ageing and NDDs. [Display omitted] • The processes contributing to region-specific selective neuronal vulnerability (SNV) and their accrual during aging is underexplored in human brains. • We noted that regional mitochondrial, antioxidant and synaptic heterogeneity based on expression and phosphorylation dynamics underlies the SNV of frontal cortex (FC) and hippocampus (HC) to neurodegeneration. • Expression and phosphorylation profile of microtubule associated protein tau (MAPT) and associated kinases during ageing in FC and HC, also probably contributes to SNV. • Regions that develop first [medulla oblongata (MD)] are defined by relatively high mitochondrial, metabolic and antioxidant function contributing to neuroprotection, compared to vulnerable areas such as FC, HC, and striatum (ST), that develop later, providing the biological basis for the "last in first out" hypothesis of ageing. [ABSTRACT FROM AUTHOR]

Background: Tobacco consumption in smoking and non‐smoking forms has been consequential in the rise of oral cancer cases. Among different forms, epidemiological studies from Middle Eastern countries and rural parts of northern India have reported increasing association of oral cancer with waterpipe (hookah) smoking. However, molecular mechanisms and role played by waterpipe smoking in the onset of oral carcinogenesis remains unexplored. Methods: In this study, immortalized normal human oral keratinocytes were chronically treated with extracts of two varieties of waterpipe tobacco—crude tobacco and processed shisha. Phenotypic changes and molecular aberrations were examined using cell culture‐based assays and mass spectrometry‐based quantitative proteomic analysis, respectively. Bioinformatics analysis was utilized to analyze proteomics data and identify dysregulated pathways. Results: Our data indicate that chronic treatment with waterpipe tobacco extracts increased proliferation, invasion, migration, and significant dysregulation of protein expression in oral keratinocytes. Altered expression of proteins involved in interferon signaling pathway were observed with both varieties of tobacco. Overexpression of cholesterol metabolism and vesicle‐mediated transport proteins were identified exclusively in cells treated with crude tobacco extract. Bioinformatics analyses revealed different oncogenic response in oral cells based on the type of waterpipe tobacco used. Conclusions: This study may serve as a useful resource in understanding the early onset of oral cancer attributed to waterpipe smoking. [ABSTRACT FROM AUTHOR]

Epidermal growth factor plays a major role in breast cancer cell proliferation, survival, and metastasis. Quercetin, a bioactive flavonoid, is shown to exhibit anticarcinogenic effects against various cancers including breast cancer. Hence, the present study was designed to evaluate the effects of gold nanoparticles-conjugated quercetin (AuNPs-Qu-5) in MCF-7 and MDA-MB-231 breast cancer cell lines. Borohydride reduced AuNPs were synthesized and conjugated with quercetin to yield AuNPs-Qu-5. Both were thoroughly characterized by several physicochemical techniques, and their cytotoxic effects were assessed by MTT assay. Apoptotic studies such as DAPI, AO/EtBr dual staining, and annexin V-FITC staining were performed. AuNPs and AuNPs-Qu-5 were spherical with crystalline nature, and the size of particles range from 3.0 to 4.5 nm. AuNPs-Qu-5 exhibited lower IC50 value compared to free Qu. There was a considerable increase in apoptotic population with increased nuclear condensation seen upon treatment with AuNPs-Qu-5. To delineate the molecular mechanism behind its apoptotic role, we analysed the proteins involved in apoptosis and epidermal growth factor receptor (EGFR)-mediated PI3K/Akt/GSK-3β signalling by immunoblotting and immunocytochemistry. The pro-apoptotic proteins (Bax, Caspase-3) were found to be up regulated and anti-apoptotic protein (Bcl-2) was down regulated on treatment with AuNPs-Qu-5. Additionally, AuNPs-Qu-5 treatment inhibited the EGFR and its downstream signalling molecules PI3K/Akt/mTOR/GSK-3β. In conclusion, administration of AuNPs-Qu-5 in breast cancer cell lines curtails cell proliferation through induction of apoptosis and also suppresses EGFR signalling. AuNPs-Qu-5 is more potent than free quercetin in causing cancer cell death, and hence, this could be a potential drug delivery system in breast cancer therapy. [ABSTRACT FROM AUTHOR]