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Adams, C. D.

Publications and source records attributed to Adams, C. D..

4 recordsLinked to original sources

Profile of the somatic mutational landscape in breast tumors from Hispanic/Latina women

Breast cancer causes the most cancer deaths among Hispanic/Latinas (H/L). However, limited tumor-sequencing data from H/L are available to guide treatment. To address this gap, we performed whole-exome sequencing of DNA from 140 HL germline and 146 matched breast tumors and RNA-seq for the tumors. We generated somatic-mutation profiles, identified copy-number alterations (CNAs), and compared results to non-Hispanic White (White) women in The Cancer Genome Atlas. Similar to Whites, PIK3CA and TP53 were the most commonly mutated genes in breast tumors from H/L. We found 4 common COSMIC mutation signatures (1, 2, 3, 13) and signature 16 not previously reported in other breast-cancer datasets. We observed recurrent amplifications in breast-cancer drivers including MYC, FGFR1, CCND1, and ERBB2, and a recurrent amplification on 17q11.2 associated with high KIAA0100 gene expression, implicated in breast-cancer aggressiveness. Expanded research is required to determine how these characteristics of H/L tumors impact treatment response and survival.

cancer biology↗

Circulating glutamine and Alzheimer’s disease: a Mendelian randomization study

INTRODUCTIONAlzheimers disease is a devastating neurodegenerative disorder. Its worldwide prevalence is over 24 million and is expected to double by 2040. Finding ways to prevent its cognitive decline is urgent.\n\nMETHODSA two-sample Mendelian randomization study was performed instrumenting glutamine, which is abundant in blood, capable of crossing the blood-brain barrier, and involved in a metabolic cycle with glutamate in the brain.\n\nRESULTSThe results reveal a protective effect of circulating glutamine (inverse-variance weighted method, odds ratio per 1-SD increase in circulating glutamine = 0.83; 95% CI 0.71, 0.97; P = 0.02).\n\nCONCLUSIONThese findings lend credence to the emerging story supporting the modifiability of glutamine/glutamate metabolism for the prevention of cognitive decline. More circulating glutamine might mean that more substrate is available during times of stress, acting as a neuroprotectant. Modifications to exogenous glutamine may be worth exploring in future efforts to prevent and/or treat Alzheimers disease.

neuroscience↗

Epithelial ovarian cancer and schizophrenia and schizophrenia on circulating glycerophosphocholine metabolites: a Mendelian randomization study

Most women with epithelial ovarian cancer (EOC) present with late-stage disease. As a result, globally, EOC is responsible for more than 150,000 deaths a year. Thus, a better understanding of risk factors for developing EOC is crucial for earlier screening and detection to improve survival. To that effort, there have been suggestions that there is an association of schizophrenia and cancer, possibly because metabolic changes are a hallmark of both cancer and schizophrenia (SZ). Perturbed choline metabolism has been documented in both diseases. Our objective was to use Mendelian randomization to evaluate whether SZ increased risk for developing EOC or the converse, and, whether SZ impacted glycerophosphocholine (GPC) metabolites. We found that SZ conferred a weak but increased risk for EOC, but not the reverse (no evidence that EOC caused SZ). SZ was also causally associated with lower levels of two GPC species and with suggestively lower levels in an additional three GPCs. We postulate that perturbed choline metabolism in SZ may mimic or contribute to a \"cholinic\" phenotype, as observed in EOC cells.

genetics↗

Activation of lateral hypothalamic group III mGluRs suppresses drug-seeking following abstinence and cocaine-associated increases in excitatory drive to orexin/hypocretin cells

The perifornical/lateral hypothalamic area (LHA) orexin (hypocretin) system is involved in drug-seeking behavior elicited by drug-associated stimuli. Cocaine exposure is associated with presynaptic plasticity at LHA orexin cells such that excitatory input to orexin cells is enhanced, both acutely and into withdrawal. These changes may augment orexin cell reactivity to drug-related cues during abstinence and contribute to relapse-like behavior. Studies in hypothalamic slices from drug-naive animals indicate that agonism of group III metabotropic glutamate receptors (mGluRs) reduces presynaptic glutamate release onto orexin cells. Therefore, we examined the group III mGluR system as a potential target to reduce orexin cell excitability in-vivo, and tested whether activating these receptors could normalize orexin cell activity following cocaine and reduce cocaine-seeking elicited by drug-associated stimuli during abstinence. First, we verified that group III mGluRs regulate orexin cell activity in vivo by showing that intra-LHA infusions of the selective agonist L-(+)-2-Amino-4-phosphonobutyric acid (L-AP4) reduces Fos expression in orexin cells following 24h food deprivation. Next, we extended these findings to show that intra-LHA L-AP4 infusions reduced discriminative stimulus-driven cocaine-seeking following withdrawal. L-AP4 had no effect on general motor activity of sucrose self-administration. Finally, using whole-cell patch clamp recordings from identified orexin cells in orexin-GFP transgenic mice, we show that enhanced presynaptic drive to orexin cells persists for up to 14d into withdrawal and that this plasticity is normalized by L-AP4. L-AP4 had no effect on measures of postsynaptic plasticity in cocaine-exposed animals. Together, these data indicate that agonism of LHA group III mGluRs reduces orexin cell activity in-vivo and is an effective strategy to suppress cocaine-seeking behavior following withdrawal. These effects are likely mediated, at least in part, by normalization of presynaptic plasticity at orexin cells that occurs as a result of cocaine exposure.

neuroscience↗