Alterations in the mammary gland and tumor microenvironment of formerly obese mice.

BACKGROUND: Obesity is a risk factor for breast cancer, and women with obesity that develop breast cancer have a worsened prognosis. Within the mammary gland, obesity causes chronic, macrophage-driven inflammation and adipose tissue fibrosis. Weight loss is a recommended intervention to resolve obesity, but the impact of weight loss on the mammary gland microenvironment and in tumors has not been well identified. METHODS: To examine the effects of weight loss following obesity, mice were fed a high-fat diet for 16 weeks to induce obesity, then switched to a low-fat diet for 6 weeks. We examined changes in immune cells, including fibrocytes, which are myeloid lineage cells that have attributes of both macrophages and myofibroblasts, and collagen deposition within the mammary glands of non-tumor-bearing mice and within the tumors of mice that were transplanted with estrogen receptor alpha positive TC2 tumor cells. RESULTS: In formerly obese mice, we observed reduced numbers of crown-like structures and fibrocytes in mammary glands, while collagen deposition was not resolved with weight loss. Following transplant of TC2 tumor cells into the mammary glands of lean, obese, and formerly obese mice, diminished collagen deposition and cancer-associated fibroblasts were observed in tumors from formerly obese mice compared to obese mice. Within tumors of obese mice, increased myeloid-derived suppressor cells and diminished CD8+ T cells were identified, while the microenvironment of tumors of formerly obese mice were more similar to tumors from lean mice. When TC2 tumor cells were mixed with CD11b+CD34+ myeloid progenitor cells, which are the cells of origin for fibrocytes, and transplanted into mammary glands of lean and obese mice, collagen deposition within the tumors of both lean and obese was significantly greater than when tumor cells were mixed with CD11b+CD34- monocytes or total CD45+ immune cells. CONCLUSIONS: Overall, these studies demonstrate that weight loss resolved some of the microenvironmental conditions within the mammary gland that may contribute to tumor progression. Additionally, fibrocytes may contribute to early collagen deposition in mammary tumors of obese mice leading to the growth of desmoplastic tumors.

Is Methotrexate Ototoxic? Investigating the Ototoxic Late Effects of Pediatric Cancer Treatment.

PURPOSE: Pediatric cancer survivors often experience long-term adverse health conditions or late effects, including hearing loss, that are attributable to cancer therapy. Ototoxic late effects have been documented in patients with cancer treated with cisplatin-based chemotherapy and/or radiation. This study evaluated the late effects of methotrexate as compared to cisplatin and other cancer therapy agents on pediatric cancer survivors at the Children's Hospital of New Orleans in Louisiana (CHNOLA) and patients currently undergoing cancer treatment at Our Lady of the Lake (OLOL) Hospital in Baton Rouge, Louisiana. METHOD: A retrospective chart review was conducted of medical records from the CHNOLA Audiology Clinic and the Treatment After Cancer Late Effects clinic, which followed patients 2-19 years after cancer treatment completion and current patients with pediatric cancer at OLOL. This study identified pediatric cancer survivors between 2 and 24 years of age with treatment protocol information and audiological evaluations. Association studies were performed to calculate p values using an exact chi-square test. RESULTS: More than 44% of late-effects patients had significant hearing loss; mild-to-profound hearing loss was observed in 37.5% of patients who received methotrexate treatment without cisplatin or irradiation. Eighty-three percent of the patients who received cisplatin had late-effect hearing loss. In patients currently receiving cancer treatment, 12% had significant hearing loss. CONCLUSIONS: The results from this study suggest that children who receive therapies not clinically established as ototoxic (i.e., methotrexate) may still be at a high risk of developing long-term hearing loss as a late effect. Due to the high incidence rate of hearing loss among patients with pediatric cancer, we recommend that audiologists be part of the late-effects care team. This study also demonstrates that patients with pediatric cancer treated with methotrexate should receive routine long-term auditory monitoring as part of their standard of care to detect and manage hearing loss early, minimizing adverse outcomes.

Alterations in the Mammary Gland and Tumor Microenvironment of Formerly Obese Mice.

Obesity is a risk factor for breast cancer, and women with obesity that develop breast cancer have a worsened prognosis. Within the mammary gland, obesity causes chronic, macrophage-driven inflammation and adipose tissue fibrosis. To examine the impact of weight loss on the mammary microenvironment, mice were fed high-fat diet to induce obesity, then switched to a low-fat diet. In formerly obese mice, we observed reduced numbers of crown-like structures and fibrocytes in mammary glands, while collagen deposition was not resolved with weight loss. Following transplant of TC2 tumor cells into the mammary glands of lean, obese, and formerly obese mice, diminished collagen deposition and cancer-associated fibroblasts were observed in tumors from formerly obese mice compared to obese mice. When TC2 tumor cells were mixed with CD11b+CD34+ myeloid progenitor cells, collagen deposition within the tumors was significantly greater compared to when tumor cells were mixed with CD11b+CD34- monocytes, suggesting that fibrocytes contribute to early collagen deposition in mammary tumors of obese mice. Overall, these studies show that weight loss resolved some of the microenvironmental conditions within the mammary gland that may contribute to tumor progression.

Light drives the developmental progression of outer retinal function.

The complex nature of rod and cone photoreceptors and the light-evoked responsivity of bipolar cells in the mature rodent retina have been well characterized. However, little is known about the emergent light-evoked response properties of the mouse retina and the role light plays in shaping these emergent responses. We have previously demonstrated that the outer retina is responsive to green light as early as postnatal day 8 (P8). Here, we characterize the progression of both photoreceptors (rods and cones) and bipolar cell responses during development and into adulthood using ex vivo electroretinogram recordings. Our data show that the majority of photoreceptor response at P8 originates from cones and that these outputs drive second-order bipolar cell responses as early as P9. We find that the magnitude of the photoresponse increases concurrently with each passing day of postnatal development and that many functional properties of these responses, as well as the relative rod/cone contributions to the total light-evoked response, are age dependent. We compare these responses at eye opening and maturity to age-matched animals raised in darkness and found that the absence of light diminishes emergent and mature cone-to-bipolar cell signaling. Furthermore, we found cone-evoked responses to be significantly slower in dark-reared retinas. Together, this work characterizes the developmental photoresponsivity of the mouse retina while highlighting the importance of properly timed sensory input for the maturation of the first visual system synapse.

Fibrocytes enhance mammary gland fibrosis in obesity.

Obesity rates continue to rise, and obese individuals are at higher risk for multiple types of cancer, including breast cancer. Obese mammary fat is a site of chronic, macrophage-driven inflammation, which enhances fibrosis within adipose tissue. Elevated fibrosis within the mammary gland may contribute to risk for obesity-associated breast cancer. To understand how inflammation due to obesity enhanced fibrosis within mammary tissue, we utilized a high-fat diet model of obesity and elimination of CCR2 signaling in mice to identify changes in immune cell populations and their impact on fibrosis. We observed that obesity increased a population of CD11b+ cells with the ability to form myofibroblast-like colonies in vitro. This population of CD11b+ cells is consistent with fibrocytes, which have been identified in wound healing and chronic inflammatory diseases but have not been examined in obesity. In CCR2-null mice, which have limited ability to recruit myeloid lineage cells into obese adipose tissue, we observed reduced mammary fibrosis and diminished fibrocyte colony formation in vitro. Transplantation of myeloid progenitor cells, which are the cells of origin for fibrocytes, into the mammary glands of obese CCR2-null mice resulted in significantly increased myofibroblast formation. Gene expression analyses of the myeloid progenitor cell population from obese mice demonstrated enrichment for genes associated with collagen biosynthesis and extracellular matrix remodeling. Together these results show that obesity enhances recruitment of fibrocytes to promote obesity-induced fibrosis in the mammary gland.

Obesity and Fibrosis: Setting the Stage for Breast Cancer.

Obesity is a rising health concern and is linked to a worsened breast cancer prognosis. Tumor desmoplasia, which is characterized by elevated numbers of cancer-associated fibroblasts and the deposition of fibrillar collagens within the stroma, may contribute to the aggressive clinical behavior of breast cancer in obesity. A major component of the breast is adipose tissue, and fibrotic changes in adipose tissue due to obesity may contribute to breast cancer development and the biology of the resulting tumors. Adipose tissue fibrosis is a consequence of obesity that has multiple sources. Adipocytes and adipose-derived stromal cells secrete extracellular matrix composed of collagen family members and matricellular proteins that are altered by obesity. Adipose tissue also becomes a site of chronic, macrophage-driven inflammation. Macrophages exist as a diverse population within obese adipose tissue and mediate the development of fibrosis through the secretion of growth factors and matricellular proteins and interactions with other stromal cells. While weight loss is recommended to resolve obesity, the long-term effects of weight loss on adipose tissue fibrosis and inflammation within breast tissue are less clear. Increased fibrosis within breast tissue may increase the risk for tumor development as well as promote characteristics associated with tumor aggressiveness.

Social Media as a Source of Medical Information for Parents of Premature Infants: A Content Analysis of Prematurity-Related Facebook Groups.

OBJECTIVE: Parents are increasingly turning to social media for medical recommendations. Our objective was to systematically examine posts on Facebook for parents of infants hospitalized in the neonatal intensive care unit (NICU) to analyze how advice on medical topics was requested and given, and whether this advice was potentially medically inappropriate. STUDY DESIGN: One hundred Facebook groups were screened for study eligibility. In each group, up to 400 posts on medical topics were evaluated. The first 10 comments of each post were classified based on content and presence of medical advice. Appropriateness of advice was evaluated by a neonatologist. RESULTS: Of 28 groups meeting study criteria, 10 permitted access for data collection. We identified 729 posts requesting medical advice of which 29% referenced the NICU period. Posts on diagnosis and development (30 and 32% of posts, respectively) were the most common topics, and most likely to receive advice (78 and 76% of posts on these topics, respectively). We identified 238 comments containing potentially inappropriate medical advice and 30 comments recommending going against medical advice. CONCLUSION: Parents are utilizing Facebook as a source of support and medical information. Parents are most likely to give development-related advice from their own parenting experiences. The high percentage of posts requesting advice about diagnosis and development in the post-NICU stage suggests parents seek increased anticipatory guidance. KEY POINTS: · Parents of premature infants use Facebook to obtain medical advice.. · Advice was at times potentially medically inappropriate.. · Much advice focused on the post-NICU period..

Breast cancer microenvironment and obesity: challenges for therapy.

Women with obesity who develop breast cancer have a worsened prognosis with diminished survival rates and increased rates of metastasis. Obesity is also associated with decreased breast cancer response to endocrine and chemotherapeutic treatments. Studies utilizing multiple in vivo models of obesity as well as human breast tumors have enhanced our understanding of how obesity alters the breast tumor microenvironment. Changes in the complement and function of adipocytes, adipose-derived stromal cells, immune cells, and endothelial cells and remodeling of the extracellular matrix all contribute to the rapid growth of breast tumors in the context of obesity. Interactions of these cells enhance secretion of cytokines and adipokines as well as local levels of estrogen within the breast tumor microenvironment that promote resistance to multiple therapies. In this review, we will discuss our current understanding of the impact of obesity on the breast tumor microenvironment, how obesity-induced changes in cellular interactions promote resistance to breast cancer treatments, and areas for development of treatment interventions for breast cancer patients with obesity.

Human papillomavirus vaccine series follow-through: comparison of four clinics in an academic medical center.

OBJECTIVE: The Centers for Disease Control & Prevention (CDC) recommends that the human papillomavirus (HPV) vaccine series be initiated at ages 11-12 years, but many children never follow-through with the series. By examining differences in clinic-specific vaccine series follow-through rates across four clinics, we aimed to identify best practices related to communication around the vaccine and pathways to follow-through. METHODS: We used the electronic medical record (EMR) to retrospectively analyze HPV vaccine follow-through at four clinic settings. We limited the sample to children ages 11-17 who received a dose of the vaccine series at any of the clinics between January 2015 and June 2018. The primary outcome was follow-through of the HPV vaccine series within 18 months of initiation. RESULTS: A total of 3,813 patients were included in this study, 29% of which followed through with the HPV vaccine series. There was significant variability of vaccine follow-through among the clinics (p<0.001), with the Med/Peds clinic having the highest rate of follow-through (32%). After adjusting for confounding variables, multivariable analysis found that Med/Peds and Family Medicine had higher odds of HPV vaccine series follow-through than the Pediatrics clinic. CONCLUSIONS: We found that the likelihood of vaccine series follow-through was highest when the series was started in the Med/Peds and Family Medicine clinics, compared to Pediatrics and Adolescent Medicine. These results suggest that further qualitative research is needed to understand what communication strategies are most effective at facilitating HPV vaccine uptake among adolescents, and how the most effective strategies can be shared among clinics.

Genomes of ubiquitous marine and hypersaline Hydrogenovibrio, Thiomicrorhabdus and Thiomicrospira spp. encode a diversity of mechanisms to sustain chemolithoautotrophy in heterogeneous environments.

Chemolithoautotrophic bacteria from the genera Hydrogenovibrio, Thiomicrorhabdus and Thiomicrospira are common, sometimes dominant, isolates from sulfidic habitats including hydrothermal vents, soda and salt lakes and marine sediments. Their genome sequences confirm their membership in a deeply branching clade of the Gammaproteobacteria. Several adaptations to heterogeneous habitats are apparent. Their genomes include large numbers of genes for sensing and responding to their environment (EAL- and GGDEF-domain proteins and methyl-accepting chemotaxis proteins) despite their small sizes (2.1-3.1 Mbp). An array of sulfur-oxidizing complexes are encoded, likely to facilitate these organisms' use of multiple forms of reduced sulfur as electron donors. Hydrogenase genes are present in some taxa, including group 1d and 2b hydrogenases in Hydrogenovibrio marinus and H. thermophilus MA2-6, acquired via horizontal gene transfer. In addition to high-affinity cbb3 cytochrome c oxidase, some also encode cytochrome bd-type quinol oxidase or ba3 -type cytochrome c oxidase, which could facilitate growth under different oxygen tensions, or maintain redox balance. Carboxysome operons are present in most, with genes downstream encoding transporters from four evolutionarily distinct families, which may act with the carboxysomes to form CO2 concentrating mechanisms. These adaptations to habitat variability likely contribute to the cosmopolitan distribution of these organisms.

The ω Subunit Governs RNA Polymerase Stability and Transcriptional Specificity in Staphylococcus aureus.

Staphylococcus aureus is a major human pathogen that causes infection in a wide variety of sites within the human body. Its ability to adapt to the human host and to produce a successful infection requires precise orchestration of gene expression. While DNA-dependent RNA polymerase (RNAP) is generally well characterized, the roles of several small accessory subunits within the complex have yet to be fully explored. This is particularly true for the omega (ω or RpoZ) subunit, which has been extensively studied in Gram-negative bacteria but largely neglected in Gram-positive counterparts. In Escherichia coli, it has been shown that ppGpp binding, and thus control of the stringent response, is facilitated by ω. Interestingly, key residues that facilitate ppGpp binding by ω are not conserved in S. aureus, and consequently, survival under starvation conditions is unaffected by rpoZ deletion. Further to this, ω-lacking strains of S. aureus display structural changes in the RNAP complex, which result from increased degradation and misfolding of the ß' subunit, alterations in δ and σ factor abundance, and a general dissociation of RNAP in the absence of ω. Through RNA sequencing analysis we detected a variety of transcriptional changes in the rpoZ-deficient strain, presumably as a response to the negative effects of ω depletion on the transcription machinery. These transcriptional changes translated to an impaired ability of the rpoZ mutant to resist stress and to fully form a biofilm. Collectively, our data underline, for the first time, the importance of ω for RNAP stability, function, and cellular physiology in S. aureus IMPORTANCE: In order for bacteria to adjust to changing environments, such as within the host, the transcriptional process must be tightly controlled. Transcription is carried out by DNA-dependent RNA polymerase (RNAP). In addition to its major subunits (α2ßß') a fifth, smaller subunit, ω, is present in all forms of life. Although this small subunit is well studied in eukaryotes and Gram-negative bacteria, only limited information is available for Gram-positive and pathogenic species. In this study, we investigated the structural and functional importance of ω, revealing key roles in subunit folding/stability, complex assembly, and maintenance of transcriptional integrity. Collectively, our data underline, for the first time, the importance of ω for RNAP function and cellular harmony in S. aureus.

Predicting verbal fluency using Word Reading: Implications for premorbid functioning.

The estimation of premorbid general intellectual functioning using word reading tests has a rich history of validation and is a common assessment practice for neuropsychologists. What is less well-researched is the approach used to estimate premorbid functioning of non-intellectual domains, such as executive functions, including verbal fluency. The current study evaluated this relationship with 41 adult college students who completed the Word Reading subtest of the Wechsler Individual Achievement Test-Second Edition (WIAT-II) and the Verbal Fluency test from the Delis-Kaplan Executive Function System (D-KEFS). Path analysis indicated that only Letter Fluency (a measure of phonemic fluency) was statistically significantly related to Word Reading and the relationship was somewhat weak. The relationship between Category Fluency (a measure of semantic fluency) and Category Switching (a measure of verbal fluency cognitive set-shifting) to Word Reading was nonsignificant. Participants also completed the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), and as expected a strong relationship was found between Word Reading and the Verbal IQ (VIQ), Performance IQ (PIQ), and Full Scale Intelligence Quotient (FSIQ). Results of this study strongly suggest that caution be exercised when extrapolating an estimate of premorbid verbal fluency abilities from measures of word reading.