Neuroimaging, cancer, and cognition: state of the knowledge

OBJECTIVES: To review neuroimaging research concerning cancer- and cancer treatment-related changes in brain structure and function, clinical perspectives, and future directions. DATA SOURCES: Peer-reviewed literature. CONCLUSION: Cancer and chemotherapy are associated with cerebral structural and functional alterations in breast cancer patients that may persist for years; many of these changes are correlated with cognitive complaints or performance. In other cancers there is some evidence that metabolism is altered by cancer, but more research is needed. IMPLICATIONS FOR NURSING PRACTICE: Understanding the role of neuroimaging is important to identify the basis of cognitive changes associated with cancer and cancer treatment

Expression of aT4g27260/GH3-5/GH3a studied with in situ hybridization

Abstract only availableTropisms, the responses of plants to external stimuli, have been studied as important evolutionary adaptations and as possible areas of future advantageous genetic manipulation. The goal of our current research is to identify targets of NPH4/ARF7 activity in the elongating hypocotyl cells of tropically-stimulated seedlings. The finding that NPH4/ARF7 is necessary for establishment of phototropic and gravitropic curvature lends credence to the long-held notion that a tropic curve requires formation and response to localized changes in auxin concentration. As a result of previous microarray experiments, we have isolated a suite of eight targets that are potentially under the control of NPH4/ARF7, and therefore acting in response to an auxin gradient. One of the targets is a member of the GH3 family, At4g27260/GH3-5/GH3a. Many of the GH3 family members have been shown to be responsive to, or to be regulated by, auxin. In order to elucidate the expression of At4g27260/GH3-5/GH3a in tropically-stimulated Brassica seedlings, in situ hybridization with sense and antisense RNA probes is being performed. These experiments are meant to clarify where At4g27260/GH3-5/GH3a is expressed in the stem in response to tropic stimulation. These experiments will provide critical insight into how At4g27260/GH3-5/GH3a is regulated under physiological conditions and suggest future experiments to test the functional significance of the encoded protein in the establishment of tropic curves.Plant Genomics Internship @ M

Cancer-Related Cognitive Outcomes Among Older Breast Cancer Survivors in the Thinking and Living With Cancer Study

Purpose To determine treatment and aging-related effects on longitudinal cognitive function in older breast cancer survivors. Methods Newly diagnosed nonmetastatic breast cancer survivors (n = 344) and matched controls without cancer (n = 347) 60 years of age and older without dementia or neurologic disease were recruited between August 2010 and December 2015. Data collection occurred during presystemic treatment/control enrollment and at 12 and 24 months through biospecimens; surveys; self-reported Functional Assessment of Cancer Therapy-Cognitive Function; and neuropsychological tests that measured attention, processing speed, and executive function (APE) and learning and memory (LM). Linear mixed-effects models tested two-way interactions of treatment group (control, chemotherapy with or without hormonal therapy, and hormonal therapy) and time and explored three-way interactions of ApoE (ε4+ v not) by group by time; covariates included baseline age, frailty, race, and cognitive reserve. Results Survivors and controls were 60 to 98 years of age, were well educated, and had similar baseline cognitive scores. Treatment was related to longitudinal cognition scores, with survivors who received chemotherapy having increasingly worse APE scores (P = .05) and those initiating hormonal therapy having lower LM scores at 12 months (P = .03) than other groups. These group-by-time differences varied by ApoE genotype, where only ε4+ survivors receiving hormone therapy had short-term decreases in adjusted LM scores (three-way interaction P = .03). For APE, the three-way interaction was not significant (P = .14), but scores were significantly lower for ε4+ survivors exposed to chemotherapy (−0.40; 95% CI, −0.79 to −0.01) at 24 months than ε4+ controls (0.01; 95% CI, 0.16 to 0.18; P < .05). Increasing age was associated with lower baseline scores on all cognitive measures (P < .001); frailty was associated with baseline APE and self-reported decline (P < .001). Conclusion Breast cancer systemic treatment and aging-related phenotypes and genotypes are associated with longitudinal decreases in cognitive function scores in older survivors. These data could inform treatment decision making and survivorship care planning

Genome-wide pathway analysis of memory impairment in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort

poster abstractMemory deficits are prominent features of mild cognitive impairment (MCI) and Alzheimer’s disease (AD). The genetic architecture underlying these memory deficits likely involves the combined effects of multiple genetic variants operative within numerous biological pathways. In order to identify functional pathways associated with memory impairment, we performed a pathway enrichment analysis on genome-wide association data from 742 Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants. A composite measure of memory was generated as the phenotype for this analysis by applying modern psychometric theory to item-level data from the ADNI neuropsychological test battery. Using the GSA-SNP software tool, we identified 27 canonical, expertly-curated pathways with enrichment (FDR-corrected p-value < 0.05) against this composite memory score. Processes classically understood to be involved in memory consolidation, such as neurotransmitter receptor-mediated calcium signaling and long-term potentiation, were highly represented among the enriched pathways. In addition, pathways related to cell adhesion, neuronal differentiation and guided outgrowth, and glucose- and inflammation-related signaling were also enriched. Among genes that were highly-represented in these enriched pathways, we found indications of coordinated relationships, including one large gene set that is subject to regulation by the SP1 transcription factor, and another set that displays co-localized expression in normal brain tissue along with known AD risk genes. These results 1) highlight key pathways and their candidate genes that appear to underlie susceptibility to memory impairment in this population, 2) suggest mechanistic targets for future studies related to diagnosis and treatment of memory deficits, and 3) validate the promise of pathway analysis in elucidating key processes underlying complex traits

Protective Effects of APOE ε2 Genotype on Cognition in Older Breast Cancer Survivors: The Thinking and Living With Cancer Study

Background: Cancer-related cognitive decline (CRCD) has been linked to apolipoprotein E (APOE) gene ε4 polymorphisms. APOE ε4 polymorphisms are also the strongest genetic risk for late-onset Alzheimer disease (AD), whereas ε2 polymorphisms protect against AD. However, the effects of ε2 polymorphisms on CRCD have not been evaluated. Methods: We evaluated nonmetastatic breast cancer survivors (n = 427) and matched noncancer controls (n = 407) ages 60-98 years assessed presystemic therapy from August 2010 to December 2017 with annual follow-up to 24 months. Neuropsychological assessment measured attention, processing speed, executive function, and learning and memory. Linear mixed-effects models tested the effects of having an ε2 allele (vs none) on longitudinal cognitive domain z scores by treatment group (chemotherapy with or without hormonal therapy, hormonal therapy, and control) controlling for covariates; participants with ε2/ε4 genotype were excluded. Sensitivity analyses examined effects of other covariates and any ε4 positivity. Results: There was an interaction with genotype for attention, processing speed, and executive functioning domain scores (Beta = 0.32, 95% confidence interval = 0.00 to 0.65); the chemotherapy group with an ε2 allele had higher scores at baseline and maintained higher scores over time compared with those without an ε2 allele, and this protective effect was not seen for other groups. There was no effect of ε2 on learning and memory domain scores. Conclusions: APOE ε2 polymorphisms may protect against CRCD in older breast cancer survivors receiving chemotherapy. With replication, this information could be useful for survivorship care and informing future studies of possible links to AD and defining mechanisms of protection

Functional microRNAs in Alzheimer’s disease and cancer: differential regulation of common mechanisms and pathways

Two of the main research priorities in the United States are cancer and neurodegenerative diseases, which are attributed to abnormal patterns of cellular behavior. MicroRNAs (miRNA) have been implicated as regulators of cellular metabolism, and thus are an active topic of investigation in both disease areas. There is presently a more extensive body of work on the role of miRNAs in cancer compared to neurodegenerative diseases, and therefore it may be useful to examine whether there is any concordance between the functional roles of miRNAs in these diseases. As a case study, the roles of miRNAs in Alzheimer’s disease (AD) and their functions in various cancers will be compared. A number of miRNA expression patterns are altered in individuals with AD compared with healthy older adults. Among these, some have also been shown to correlate with neuropathological changes including plaque and tangle accumulation, as well as expression levels of other molecules known to be involved in disease pathology. Importantly, these miRNAs have also been shown to have differential expression and or functional roles in various types of cancer. To examine possible intersections between miRNA functions in cancer and AD, we review the current literature on eight of these miRNAs in cancer and AD, focusing on their roles in known biological pathways. We propose a pathway-driven model in which some molecular processes show an inverse relationship between cancer and neurodegenerative disease (e.g., proliferation and apoptosis) whereas others are more parallel in their activity (e.g., immune activation and inflammation). A critical review of these and other molecular mechanisms in cancer may shed light on the pathophysiology of AD, and highlight key areas for future research. Conclusions from this work may be extended to other neurodegenerative diseases for which some molecular pathways have been identified but which have not yet been extensively researched for miRNA involvement