Cocaine use disorder effects on blood oxytocin levels and OXTR DNA methylation.

Substance use disorders have been associated with alterations in the oxytocinergic system, but few studies have investigated both the peptide and epigenetic mechanisms potentially implicated in the regulation of oxytocin receptor. In this study, we compared plasma oxytocin and blood DNA methylation in the OXTR gene between people with and without cocaine use disorder (CUD). We measured the oxytocin levels of 51 people with CUD during acute abstinence and of 30 healthy controls using an enzyme immunoassay. The levels of DNA methylation in four CpG sites at exon III of the OXTR gene were evaluated in a subsample using pyrosequencing. The Addiction Severity Index was used to assess clinical characteristics. We found higher oxytocin levels in men with CUD (56.5 pg/mL; 95% CI: 48.2-64.7) than in control men (33.6 pg/mL; 95% CI: 20.7-46.5), while no differences between women with and without CUD were detected. With a moderate effect size, the interaction effect between group and sex remained significant when controlling for height, weight and age data. A positive correlation in the CUD sample was found between oxytocin levels and days of psychological suffering prior to treatment enrollment. No group differences were observed regarding DNA methylation data. This suggests that CUD is associated with higher peripheral oxytocin levels in men during acute abstinence. This finding may be considered in future studies that aim at using exogenous oxytocin as a potential treatment for cocaine addiction.

Interrelated but Not Time-Aligned Response in Myogenic Regulatory Factors Demethylation and mRNA Expression after Divergent Exercise Bouts.

INTRODUCTION: DNA methylation regulates exercise-induced changes in the skeletal muscle transcriptome. However, the specificity and the time course responses in the myogenic regulatory factors DNA methylation and mRNA expression after divergent exercise modes are unknown. PURPOSE: This study aimed to compare the time course changes in DNA methylation and mRNA expression for selected myogenic regulatory factors ( MYOD1 , MYF5 , and MYF6 ) immediately after, 4 h after, and 8 h after a single bout of resistance exercise (RE), high-intensity interval exercise (HIIE), and concurrent exercise (CE). METHODS: Nine healthy but untrained males (age, 23.9 ± 2.8 yr; body mass, 70.1 ± 14.9 kg; peak oxygen uptake [V̇O 2peak ], 41.4 ± 5.2 mL·kg -1 ·min -1 ; mean ± SD) performed a counterbalanced, randomized order of RE (4 × 8-12 repetition maximum), HIIE (12 × 1 min sprints at V̇O 2peak running velocity), and CE (RE followed by HIIE). Skeletal muscle biopsies (vastus lateralis) were taken before (REST) immediately (0 h), 4 h, and 8 h after each exercise bout. RESULTS: Compared with REST, MYOD1 , MYF5 , and MYF6 , mean methylation across all CpGs analyzed was reduced after 4 and 8 h in response to all exercise protocols ( P < 0.05). Reduced levels of MYOD1 methylation were observed after HIIE and CE compared with RE ( P < 0.05). Compared with REST, all exercise bouts increased mRNA expression over time ( MYOD1 at 4 and 8 h, and MYF6 at 4 h; P < 0.05). MYF5 mRNA expression was lower after 4 h compared with 0 h and higher at 8 h compared with 4 h ( P < 0.05). CONCLUSIONS: We observed an interrelated but not time-aligned response between the exercise-induced changes in myogenic regulatory factors demethylation and mRNA expression after divergent exercise modes. Despite divergent contractile stimuli, changes in DNA methylation and mRNA expression in skeletal muscle were largely confined to the late (4-8 h) recovery period and similar between the different exercise challenges.

Comprehensive immunohistochemical analysis of RET, BCAR1, and BCAR3 expression in patients with Luminal A and B breast cancer subtypes.

PURPOSE: Breast cancer (BC) is considered a heterogeneous disease composed of distinct subtypes with diverse clinical outcomes. Luminal subtype tumors have the best prognosis, and patients benefit from endocrine therapy. However, resistance to endocrine therapies in BC is an obstacle to successful treatment, and novel biomarkers are needed to understand and overcome this mechanism. The RET, BCAR1, and BCAR3 genes may be associated with BC progression and endocrine resistance. METHODS: Aiming to evaluate the expression profile and prognostic value of RET, BCAR1, and BCAR3, we performed immunohistochemistry on tissue microarrays (TMAs) containing a cohort of 361 Luminal subtype BC. RESULTS: Low expression levels of these three proteins were predominantly observed. BCAR1 expression was correlated with nuclear grade (p = 0.057), and BCAR3 expression was correlated with lymph node status (p = 0.011) and response to hormonal therapy (p = 0.021). Further, low expression of either BCAR1 or BCAR3 was significantly associated with poor prognosis (p = 0.005; p = 0.042). Pairwise analysis showed that patients with tumors with low BCAR1/low BCAR3 expression had a poorer overall survival (p = 0.013), and the low BCAR3 expression had the worst prognosis with RET high expression stratifying these patients into two different groups. Regarding the response to hormonal therapy, non-responder patients presented lower expression of RET in comparison to the responder group (p = 0.035). Additionally, the low BCAR1 expression patients had poorer outcomes than BCAR1 high (p = 0.015). CONCLUSION: Our findings suggest RET, BCAR1, and BCAR3 as potential candidate markers for endocrine therapy resistance in Luminal BC.

Effects of intrauterine exposure to concentrated ambient particles on allergic sensitization in juvenile mice.

Intrauterine exposure to particulate matter (PM) has been associated with an increased risk of asthma development, which may differ by the age of asthma onset, sex, and pollutant concentration. To investigate the pulmonary effects of in utero exposure to concentrated urban ambient particles (CAPs) in response to house dust mite (HDM) sensitization in juvenile mice. Mice were exposed to CAPs (600 µg/m3 PM2.5) during the gestational period. Twenty-two-day postnatal mice were sensitized with HDM (100 µg, intranasally, 3 times per week). Airway responsiveness (AHR), serum immunoglobulin, and lung inflammation were assessed after 43 days of the postnatal period. Female (n = 47) and male (n = 43) mice were divided into four groups as follows: (1) FA: not exposed to CAPs; (2) CAPs: exposed to CAPs; (3) HDM: sensitized to HDM; and (4) CAPs+HDM: exposed to CAPs and HDM-sensitized. PM2.5 exposure did not worsen lung hyperresponsiveness or allergic inflammation in sensitized animals. The levels of the lung cytokines IL-4, TNF-α, and IL-2 were differentially altered in male and female animals. Males presented hyporesponsiveness and increased lung macrophagic inflammation. There were no epigenetic changes in the IL-4 gene. In conclusion, intrauterine exposure ambient PM2.5 did not worsened allergic pulmonary susceptibility but affected the pulmonary immune profile and lung function, which differed by sex.

Abnormal Long Non-Coding RNAs Expression Patterns Have the Potential Ability for Predicting Survival and Treatment Response in Breast Cancer.

Abnormal long non-coding RNAs (lncRNAs) expression has been documented to have oncogene or tumor suppressor functions in the development and progression of cancer, emerging as promising independent biomarkers for molecular cancer stratification and patients' prognosis. Examining the relationship between lncRNAs and the survival rates in malignancies creates new scenarios for precision medicine and targeted therapy. Breast cancer (BRCA) is a heterogeneous malignancy. Despite advances in its molecular classification, there are still gaps to explain in its multifaceted presentations and a substantial lack of biomarkers that can better predict patients' prognosis in response to different therapeutic strategies. Here, we performed a re-analysis of gene expression data generated using cDNA microarrays in a previous study of our group, aiming to identify differentially expressed lncRNAs (DELncRNAs) with a potential predictive value for response to treatment with taxanes in breast cancer patients. Results revealed 157 DELncRNAs (90 up- and 67 down-regulated). We validated these new biomarkers as having prognostic and predictive value for breast cancer using in silico analysis in public databases. Data from TCGA showed that compared to normal tissue, MIAT was up-regulated, while KCNQ1OT1, LOC100270804, and FLJ10038 were down-regulated in breast tumor tissues. KCNQ1OT1, LOC100270804, and FLJ10038 median levels were found to be significantly higher in the luminal subtype. The ROC plotter platform results showed that reduced expression of these three DElncRNAs was associated with breast cancer patients who did not respond to taxane treatment. Kaplan-Meier survival analysis revealed that a lower expression of the selected lncRNAs was significantly associated with worse relapse-free survival (RFS) in breast cancer patients. Further validation of the expression of these DELncRNAs might be helpful to better tailor breast cancer prognosis and treatment.

Oxytocin Receptor Exon III Methylation in the Umbilical Cord Blood of Newborns With Prenatal Exposure to Crack Cocaine.

BACKGROUND: Prenatal cocaine exposure (PCE) is associated with behavioral, cognitive, and social consequences in children that might persist into later development. However, there are still few data concerning epigenetic mechanisms associated with the effects of gestational cocaine exposure, particularly in human newborns. AIMS: We investigated the effects of PCE on DNA methylation patterns of the Oxytocin Receptor (OXTR) gene in the umbilical cord blood (UCB). The relationship between UCB DNA methylation levels and the severity of the mother's cocaine use during pregnancy was also evaluated. METHODS: In this cross-sectional study, 28 UCB samples of newborns with a history of crack cocaine exposure in utero and 30 UCB samples of non-exposed newborns (NEC) were compared for DNA methylation levels at two genomic loci located in exon III of the OXTR gene (OXTR1 and OXTR2) through pyrosequencing. Maternal psychopathology was investigated using the Mini International Neuropsychiatric Interview, and substance use characteristics and addiction severity were assessed using the Smoking and Substance Involvement Screening Test (ASSIST). RESULTS: No differences between newborns with a history of PCE and NEC were observed in OXTR1 or OXTR2 DNA methylation levels. However, regression analyses showed that maternal addiction severity for crack cocaine use predicted OXTR1 DNA methylation in newborns. CONCLUSION: These data suggest that OXTR methylation levels in the UCB of children are affected by the severity of maternal crack cocaine usage. Larger studies are likely to detect specific changes in DNA methylation relevant to the consequences of PCE.

Prostate apoptosis response 4 (PAR4) expression modulates WNT signaling pathways in MCF7 breast cancer cells: A possible mechanism underlying PAR4-mediated docetaxel chemosensitivity.

Docetaxel is an effective drug for the treatment of metastatic breast cancer. However, the exact mechanisms and/or markers associated with chemosensitivity or resistance to docetaxel remain unclear. We previously showed that the expression of prostate apoptosis response 4 (PAR4) inhibits the growth of MCF7 breast cancer cells and increases their sensitivity to docetaxel. Using cDNA microarray analysis, we evaluated transcriptome changes in MCF7 cells expressing increased levels of PAR4 and control cells before and after docetaxel treatment. Some of the top gene networks generated from the differentially expressed genes were related to the wingless­type MMTV integration 1 (WNT) canonical (WNT/ß-catenin) and non­canonical (ß­catenin­independent) pathways. The Human WNT signaling pathway RT2 profiler™ PCR array was used to validate the effects of PAR4 on the expression pattern of genes involved in the WNT pathway. CACNAD2A3, GDF5 and IL6 were upregulated and NANOG was downregulated in the MCF7 breast cancer cells expressing increased levels of PAR4 after treatment with docetaxel, likely indicating inactivation of the WNT/ß-catenin pathway. Upregulation of FGF7, LEF1 and TWIST1 indicated activation of the WNT/ß­catenin pathway. Although preliminary, our findings could be of particular interest for understanding the action of PAR4 in chemosensitivity, particularly to increase the specificity and effectiveness of drug treatment and overcome resistance to chemotherapy. Further studies are needed to better understand the biological roles of PAR4 in the regulation of WNT pathways in breast cancer cells in response to docetaxel and other chemotherapeutic agents.

Prostate apoptosis response-4 is involved in the apoptosis response to docetaxel in MCF-7 breast cancer cells.

Experimental evidence indicates that prostate apoptosis response-4 (Par-4, also known as PAWR) is a key regulator of cancer cell survival and may be a target for cancer-selective targeted therapeutics. Par-4 was first identified in prostate cancer cells undergoing apoptosis. Both intracellular and extracellular Par-4 have been implicated in apoptosis. Relatively little is known about the role of Par-4 in breast cancer cell apoptosis. In this study, we sought to investigate the effects of Par-4 expression on cell proliferation, apoptosis and drug sensitivity in breast cancer cells. MCF-7 cells were stably transfected with expression vectors for Par-4, or transiently transfected with siRNA for Par-4 knockdown. Cell proliferation assays were performed using MTT and apoptosis was evaluated using acridine orange staining, fluorescence microscopy and flow cytometry. Par-4 overexpression reduced MCF-7 proliferation rates. Conversely, Par-4 knockdown led to increased MCF-7 proliferation. Par-4 downregulation also led to increased BCL-2 and reduced BID expression. Par-4 overexpression did not affect the cell cycle profile. However, MCF-7 cells with increased Par-4 expression showed reduced ERK phosphorylation, suggesting that the inhibition of cell proliferation promoted by Par-4 may be mediated by the MAPK/ERK1/2 pathway. MCF-7 cells with increased Par-4 expression showed a marginal increase in early apoptotic cells. Importantly, we found that Par-4 expression modulates apoptosis in response to docetaxel in MCF7 breast cancer cells. Par-4 exerts growth inhibitory effects on breast cancer cells and chemosensitizes them to docetaxel.