The underlying basis for obesity: relationship to cancer

Conjugating uncoupler compounds with hydrophobic hydrocarbon chains to achieve adipose tissue selective drug accumulation

One potential approach for treating obesity is to increase energy expenditure in brown and white adipose tissue. Here we aimed to achieve this outcome by targeting mitochondrial uncoupler compounds selectively to adipose tissue, thus avoiding side effects from uncoupling in other tissues. Selective drug accumulation in adipose tissue has been observed with many lipophilic compounds and dyes. Hence, we explored the feasibility of conjugating uncoupler compounds with a lipophilic C8-hydrocarbon chain via an ether bond. We found that substituting the trifluoromethoxy group in the uncoupler FCCP with a C8-hydrocarbon chain resulted in potent uncoupling activity. Nonetheless, the compound did not elicit therapeutic effects in mice, likely as a consequence of metabolic instability resulting from rapid ether bond cleavage. A lipophilic analog of the uncoupler compound 2,6-dinitrophenol, in which a C8-hydrocarbon chain was conjugated via an ether bond in the para-position (2,6-dinitro-4-(octyloxy)phenol), exhibited increased uncoupling activity compared to the parent compound. However, in vivo pharmacokinetics studies suggested that 2,6-dinitro-4-(octyloxy)phenol was also metabolically unstable. In conclusion, conjugation of a hydrophobic hydrocarbon chain to uncoupler compounds resulted in sustained or improved uncoupling activity. However, an ether bond linkage led to metabolic instability, indicating the need to conjugate lipophilic groups via other chemical bonds.

Exploring the anti-obesity bioactive compounds of Thymelaea hirsuta and Ziziphus spina-christi through integration of lipase inhibition screening and molecular docking analysis

Activity-guided fractionation of the ethanolic extracts of Thymelaea hirsuta and Ziziphus spina-christi furnished eight compounds with pancreatic lipase inhibitory activity. Six compounds were isolated from the chloroform fraction of T. hirsuta. It is worth mentioning that this is the first report for the isolation of 5,7,4'-trihydroxy-8-methoxycarbonyl flavanol (2), daphnodorin G-3''-methyl ether (4) and daphnodorin G (5) from genus Thymelaea. Moreover, daphnoretin (1), neochamaejasmin A (3) and daphnodorin B (6) were also isolated from the chloroform fraction of the same plant. On the other hand, quercetin 3-O-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-galactopyranoside (7) and 3-O-[α-l-fucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 3)-α-l-arabinopyranosyl] jujubogenin (christinin A) (8) were isolated from the n-butanol fraction of Z. spina-christi. Structure elucidation of the isolated compounds was carried out by detailed analysis of 1D and 2D spectral data. These compounds showed percentage inhibitions of 72% (1), 52% (2), 61.8% (3), 39% (4), 69.5% (5), 3.5% (6), 68% (7) and 75% (8) at the concentration of 250 μM and XP-G scores of lipase inhibition were 11.40 (1), 8.71 (2), 6.13 (3), 8.23 (4), 6.22 (5), 9.76 (6), 14.66 (7) and 12.00 (8). This is the first report of the isolation of lipase inhibitors from both plants T. hirsuta and Z. spina-christi. In addition to that, this might result in presenting the biscoumarin, daphnoretin, and the dammarane saponin, christinin A, as potent lipase inhibitors.

Out of step societal and Darwinian adaptation during evolution is the cause of multiple women's health issues

During human evolution, major changes in our societal conditions and environment took place without sufficient time for concomitant genetic alterations, leading to out of step adaptation and diseases in women. We first discuss recent societal adaptation mismatch (menstrual bleeding; increases in cancers of reproductive organs, endometriosis; mother's nursing; polycystic ovarian syndrome; transgenerational epigenetic modifications), followed by Darwinian out of step adaptation (labor difficulties; sex chromosomes, human diseases and sex disparity in genomic DNA). We discuss the evolutionary basis of menstrual bleeding, followed by recent increases in cancers of reproductive organs and endometriosis. The importance of breastfeeding by mothers is also emphasized. Earlier onset of menarche, decreased rates of childbirths and breastfeeding resulted in increased number of menstrual cycles in a lifetime, coupled with excess estrogen exposure and incessant ovulation, conditions that increased the susceptibility to mammary and uterine cancers as well as ovarian epithelial cancer and endometriosis. Shorter lactation duration in mothers also contributed to more menstrual cycles. We further discuss the evolutionary basis of the prevalent polycystic ovary syndrome. During the long-term Darwinian evolution, difficulties in childbirth evolved due to a narrowed pelvis, our upright walking and enlarged fetal brain sizes. Because there are 1.5% genomic DNA differences between woman and man, it is of significance to investigate sex-specific human physiology and diseases. In conclusion, understanding out of step adaptation during evolution could allow the prevention and better management of female reproductive dysfunction and diseases.

FOXO3 Expression in Macrophages Is Lowered by a High-Fat Diet and Regulates Colonic Inflammation and Tumorigenesis

Obesity, characterized by augmented inflammation and tumorigenesis, is linked to genetic predispositions, such as FOXO3 polymorphisms. As obesity is associated with aberrant macrophages infiltrating different tissues, including the colon, we aimed to identify FOXO3-dependent transcriptomic changes in macrophages that drive obesity-mediated colonic inflammation and tumorigenesis. We found that in mouse colon, high-fat-diet-(HFD)-related obesity led to diminished FOXO3 levels and increased macrophages. Transcriptomic analysis of mouse peritoneal FOXO3-deficient macrophages showed significant differentially expressed genes (DEGs; FDR < 0.05) similar to HFD obese colons. These DEG-related pathways, linked to mouse colonic inflammation and tumorigenesis, were similar to those in inflammatory bowel disease (IBD) and human colon cancer. Additionally, we identified a specific transcriptional signature for the macrophage-FOXO3 axis (MAC-FOXO382), which separated the transcriptome of affected tissue from control in both IBD (p = 5.2 × 10−8 and colon cancer (p = 1.9 × 10−11), revealing its significance in human colonic pathobiologies. Further, we identified (heatmap) and validated (qPCR) DEGs specific to FOXO3-deficient macrophages with established roles both in IBD and colon cancer (IL-1B, CXCR2, S100A8, S100A9, and TREM1) and those with unexamined roles in these colonic pathobiologies (STRA6, SERPINH1, LAMB1, NFE2L3, OLR1, DNAJC28 and VSIG10). These findings establish an important understanding of how HFD obesity and related metabolites promote colonic pathobiologies.

Browning of white adipocytes by gold nanocluster mediated electromagnetic induction heating hyperthermia

Browning of white adipose tissue (WAT) is becoming an attractive therapeutic target for obesity. Great efforts have been made to develop effective approaches to induce browning. Unfortunately, the current methods suffer from a series of disadvantages, such as low efficiency, unsatisfactory stability, and side effects. Herein, we report a new approach to induce browning of 3T3-L1 white adipocytes based on electromagnetic induction heating (EIH) hyperthermia. In particular, adipocyte-targeting aptamer modified gold nanoclusters (Apt-AuNCs) were employed as the mediators of EIH. Apt-AuNCs had good biocompatibility and excellent targeting performance with white adipocytes. After Apt-AuNCs/EIH treatment, adipocytes with characteristic multilocular and small lipid droplets increased, and the content of triglycerides reduced effectively. Apt-AuNCs/EIH treatment also significantly increased the mitochondrial activity in adipocytes. Meanwhile, the mRNA levels of key genes that are involved in browning, for example UCP1, PRDM16, PPARγ, and PGC-1α, were upregulated. Finally, the induction mechanism of Apt-AuNCs/EIH on browning of white adipocytes was explained by the synergistic effects of EIH hyperthermia and pharmacological action of AuNCs. To the best of our knowledge, this is the first attempt on induction of browning by metal nanocluster-mediated EIH hyperthermia, thus providing an interesting and efficient channel for obesity treatment.

Prognosis of Lung Adenocarcinoma Patients With NTRK3 Mutations to Immune Checkpoint Inhibitors

Background

Immune checkpoint inhibitors (ICIs) are an important treatment modality that must be considered for patients with lung adenocarcinoma (LUAD). However, ICIs are effective only in some of these patients. Therefore, identifying biomarkers that accurately predict the prognosis of patients with LUAD treated with ICIs can help maximize their therapeutic benefits. This study aimed to identify a new potential predictor to better select and optimally benefit LUAD patients.

Methods

We first collected and analyzed a discovery immunotherapy cohort comprising clinical and mutation data for LUAD patients. Then, we evaluated whether the specific mutated genes can act as predictive biomarkers in this discovery immunotherapy cohort and further validated the findings in The Cancer Genome Atlas (TCGA) project LUAD cohort. Gene set enrichment analysis (GSEA) was used to explore possible alterations in DNA damage response (DDR) pathways within the gene mutation. Moreover, we analyzed whole-exome sequencing (WES) and drug sensitivity response data for LUAD cell lines in the Genomics of Drug Sensitivity in Cancer (GDSC) database.

Results

Among the mutated genes screened from both the ICI treatment and TCGA-LUAD cohorts, NTRK3 mutation (mutant-type NTRK3, NTRK3-MT) was strongly associated with immunotherapy. First, significant differences in overall survival (OS) were observed between patients with NTRK3-MT and those with NTRK3-WT in the ICI treatment cohort but not in the non-ICI-treated TCGA-LUAD cohort. We then analyzed the association of NTRK3-MT with clinical characteristics and found the tumor mutation burden (TMB) to be significantly higher in both NTRK3-MT cohorts. However, significant differences in neoantigen levels and smoking history were found only for NTRK3-MT in the LUAD cohort from TCGA. Furthermore, some immune-related genes and immune cell-related genes were significantly upregulated in patients with NTRK3-MT compared to those with NTRK3-WT. In addition, NTRK3 mutation affected the deregulation of some signaling pathways and the DDR pathway.

Conclusions

Our findings suggest that NTRK3-MT can predict the prognosis of patients with LUAD treated by ICIs and that it may have clinical significance for immunotherapy.

Cranberry Polyphenolic Extract Exhibits an Antiobesity Effect on High-Fat Diet-Fed Mice through Increased Thermogenesis

BACKGROUND

Although polyphenol-rich cranberry extracts reportedly have an antiobesity effect, the exact reason for this remains unclear.

OBJECTIVES

In light of the reported health benefits of the polyphenolic compounds in cranberry, we investigated the effects and mechanism of a cranberry polyphenolic extract (CPE) in high-fat diet (HFD)-fed obese mice.

METHODS

The distributions of individual CPE compounds were characterized by HPLC fingerprinting. Male C57BL/6J mice (4 wk old) were fed for 16 wk normal diet (ND, 10% fat energy) or HFD (60% fat energy) with or without 0.75% CPE in drinking water (HFD + CPE). Body and adipose depot weights, indices of glucose metabolism, energy expenditure (EE), and expression of genes related to brown adipose tissue (BAT) thermogenesis, and inguinal/epididymal white adipose tissue (iWAT/eWAT) browning were measured.

RESULTS

After 16 wk, the body weight was 22.5% lower in the CPE-treated mice than in the HFD group but remained 17.9% higher than in the ND group. CPE treatment significantly increased EE compared with that of the ND and HFD groups. The elevated EE was linked with BAT thermogenesis, and iWAT/eWAT browning, shown by the induction of thermogenic genes, especially uncoupling protein 1 (Ucp1), and browning-related genes, including Cd137, a member of the tumor necrosis factor receptor superfamily (Tnfrsf9). The mRNA expression and abundance of uncoupling protein 1 in BAT of CPE-fed mice were 5.78 and 1.47 times higher than in the HFD group, and 0.61 and 1.12 times higher than in the ND group, respectively. Cd137 gene expression in iWAT and eWAT of CPE-fed mice were 2.35 and 3.13 times higher than in the HFD group, and 0.84 and 1.39 times higher than in the ND group, respectively.

CONCLUSIONS

Dietary CPE reduced but did not normalize HFD-induced body weight gain in male C57BL/6J mice, possibly by affecting energy metabolism.

Extrahepatic Malignancies in Nonalcoholic Fatty Liver Disease

PURPOSE OF REVIEW

Malignancy is the second most common cause of death in individuals with nonalcoholic fatty liver disease (NAFLD). Understanding unique characteristics of malignancy risk beyond hepatocellular carcinoma in NAFLD has significant implications in counseling and personalized preventative measures in this high-risk population. Herein, we systematically review the literature reporting extra-hepatic malignancies in NAFLD and discuss the key biological mechanisms underpinning the association between excess adiposity and cancer risk.

RECENT FINDINGS

Several studies have shown significant associations between NAFLD and extrahepatic malignancies. The strongest association was found with cancers of the gastrointestinal tract and hormone-sensitive cancers. Recent data support sex-specific differences in cancer risk increase in NAFLD: colorectal cancer in men and uterine cancer in women. The risk of cancer development is higher in NAFLD than obesity alone.

SUMMARY

A growing body of observational evidence over the last decade supports the association between NAFLD and extrahepatic malignancies. This association requires further studies, ideally designed to include more detailed measures of body fat deposition beyond BMI in well-characterized, large cohorts of NAFLD patients, to determine if screening policies should be individualized in this group.

Analysis of Transcriptome, Selected Intracellular Signaling Pathways, Proliferation and Apoptosis of LNCaP Cells Exposed to High Leptin Concentrations

Leptin, the first discovered adipokine, has been connected to various physiological and pathophysiological processes, including cancerogenesis. Increasing evidence confirms its influence on prostate cancer cells. However, studies on the effects of leptin on the proliferation and apoptosis of the androgen-sensitive LNCaP line of prostate cancer cells brought conflicting results. Therefore, we performed studies on the effects of high LEP concentration (1 × 10⁻⁶ M) on gene expression profile, change of selected signaling pathways, proliferation and apoptosis of LNCaP cells. RTCA (real-time cell analyzer) revealed inhibitory effect of LEP on cell proliferation, but lower LEP concentrations (10⁻⁸ and 10⁻¹⁰ M) did not affect cell division. Moreover, flow cytometry with a specific antibody for Cleaved PARP-1, an apoptosis marker, confirmed the activation of apoptosis in leptin-exposed LNCaP line of prostate cancer cells. Within 24 h LEP (10⁻⁶ M) increases expression of 297 genes and decreases expression of 119 genes. Differentially expressed genes (DEGs) were subjected to functional annotation and clusterization using the DAVID bioinformatics tools. Most ontological groups are associated with proliferation and apoptosis (seven groups), immune response (six) and extracellular matrix (two). These results were confirmed by the Gene Set Enrichment Analysis (GSEA). The leptin’s effect on apoptosis stimulation was also confirmed using Pathview library. These results were also confirmed by qPCR method. The results of Western Blot analysis (exposure to LEP 10 min, 1, 2, 4 and 24 h) suggest (after 24 h) decrease of p38 MAPK, p44-42 mitogen-activated protein kinase and Bcl-2 phosphorylated at threonine 56. Moreover, exposure of LNCaP cells to LEP significantly stimulates the secretion of matrix metallopeptidase 7 (MMP7). Obtained results suggest activation of apoptotic processes in LNCaP cells cultured at high LEP concentration. At the same time, this activation is accompanied by inhibition of proliferation of the tested cells.

Gold nanoparticles synthesized with Smilax glabra rhizome modulates the anti-obesity parameters in high-fat diet and streptozotocin induced obese diabetes rat model

Diabetes is a major emerging health consequence across the world which directly associated with the obesity. Contemporary anti-diabetic drugs have numeral limitations, and investigation of herbal remedies for diabetes give novel guide for the expansion of new drugs that can be used as harmonizing to present anti-diabetic allopathic medications. Gold nanoparticles (AuNPs) of 21 nm have been formerly well portrayed in vitro for their capability to intend active uptake in cell. Our present study was dealing with the synthesis of gold nanoparticles by means of Smilax glabra rhizome amend the anti-obesity constraints in high-fat diet by streptozotocin provoked obese diabetes in rat model. Characterization studies like UV -Spectroscopy, XRD analysis, SEM, TEM microscopy, Energy Dispersive X-Ray Spectroscopy, and FT-IR investigation confirms the availability of dimension, shape and size. Biochemical parameters like blood glucose and insulin sufferance and its release, lipid profile, aterogenic & coronary index, liver markers, inflammatory markers, hormones like leptin, resistin, adiponectin indicates the therapeutic effect of gold nanoparticles harvested from Smilax glabra on obese and diabetic rats. Histopathological examinations displayed the disturbed internal structures of obese and diabetic rats liver and heart tissues. Whereas, treatment with gold nanoparticles synthesized from Smilax glabra restored the internal membrane, nuclei and cytoplasm. All these findings confirmed the anti-obesity and anti-diabetic effect of synthesized gold nanoparticles from Smilax glabra.

Randomized trial of weight loss in primary breast cancer: Impact on body composition, circulating biomarkers and tumor characteristics

Obesity adversely impacts overall and cancer‐specific survival among breast cancer patients. Preclinical studies demonstrate negative energy balance inhibits cancer progression; however, feasibility and effects in patients are unknown. A two‐arm, single‐blinded, randomized controlled weight‐loss trial was undertaken presurgery among 32 overweight/obese, Stage 0–II breast cancer patients. The attention control arm (AC) received basic nutritional counseling and upper‐body progressive resistance training whereas the weight loss intervention (WLI) arm received identical guidance, plus counseling on caloric restriction and aerobic exercise to promote 0.68–0.92 kg/week weight loss. Anthropometrics, body composition, blood and survey data were collected at baseline and presurgery ∼30 days later. Tumor markers (e.g., Ki67) and gene expression were assessed on biopsy and surgical specimens; sera were analyzed for cytokines, growth and metabolic factors. Significant WLI vs. AC differences were seen in baseline‐to‐follow‐up changes in weight (−3.62 vs. −0.52 kg), %body fat (−1.3 vs. 0%), moderate‐to‐vigorous physical activity (+224 vs. +115 min/week), caloric density (−0.3 vs. 0 kcal/g), serum leptin (−12.3 vs. −4.0 ng/dl) and upregulation of tumor PI3Kinase signaling and cell cycle‐apoptosis related genes (CC‐ARG; all p‐values <0.05). Cytolytic CD56^dimNK cell expression was positively associated with weight loss; CC‐ARG increased with physical activity. Increased tumor (nuclear) TNFα and IL‐1β, CX3CL1 and CXCL1 gene expression was observed in the WLI. Tumor Ki67 did not differ between arms. Feasibility benchmarks included 80% accrual, 100% retention, no adverse effects and excellent adherence. Short‐term weight loss interventions are feasible; however, mixed effects on tumor biology suggest unclear benefit to presurgical caloric restriction, but possible benefits of physical activity.

What's new?

Obesity adversely impacts survival among breast cancer patients. Preclinical studies demonstrate negative energy balance inhibits cancer progression; however, effects in patients are unknown. This is the first randomized controlled trial to assess the impact of a pre‐surgical weight loss intervention among early‐stage breast cancer patients. Results show the effects of acute negative energy balance on tumor biology, circulating biomarkers, and quality‐of‐life. Short‐term weight loss interventions are feasible; however, mixed effects on tumor biology suggest unclear benefit to pre‐surgical caloric restriction. Such interventions may be better timed after surgical resection, though cell cycle‐apoptosis and DNA damage‐repair scores support increasing physical activity.

Warburg Effect Inversion: Adiposity shifts central primary metabolism in MCF-7 breast cancer cells

AIMS

Obesity is a complex health disorder and a trigger to many diseases like Diabetes mellitus (DM) and breast cancer (BrCa), both leading causes of morbidity and mortality worldwide. Also evidence demonstrates that abnormal glucose metabolism termed 'the Warburg effect' in cancer cell is closely associated with malignant phenotypes and promote the aggressiveness of several types of cancer, including BrCa. In this study, we evaluated the breast cancer cell metabolism in normoglycemia, hyperglycemia and in an obesity condition in order to clarify the potential underlined mechanisms that link these disorders.

MATERIALS AND METHODS

MCF-7 cells were exposed to low and high glucose levels, the latter either in the presence of 3T3-L1 adipocyte conditioned medium (CM), thus mimicking the adiposity observed in obese patients. Cell viability, migration, proliferation, cytotoxicity and cell death assays were performed under the different culture conditions. Hormonal and lipid profile were also characterized by biochemical assays and primary metabolism was determined by Nuclear Magnetic Resonance (NMR)-based metabolomics.

RESULTS

Our results show an increased aggressiveness in the condition mimicking diabetogenic obesity with an altered energy/lipid metabolism. Interestingly in the experimental obesity-mimicking status, lipids and amino acids were expended while glucose was produced by tumor cells from lactate. These findings reveal a shift on tumor cells metabolism that is opposite to 'the Warburg effect'.

CONCLUSIONS

Overall, this experimentally obesity-mimicking condition not only revealed an increased tumor proliferation and aggressiveness but also disclosed a new mechanism of cancer metabolism, the 'Warburg Effect Inversion'.

Vascular targeted nanotherapeutic approach for obesity treatment

Obesity is a global epidemic that poses a serious health concern due to it being a risk factor for life-threatening chronic diseases, such as type 2 diabetes, cancer, and cardiovascular diseases. Pharmacotherapy remains the mainstay for the management of obesity; however, its usefulness is limited due to poor drug efficacy, non-specificity and toxic side effects. Therefore, novel approaches that could provide insights into obesity and obesity-associated diseases as well as development of novel anti-obesity treatment modalities or improvement on the existing drugs are necessary. While the ideal treatment of obesity should involve early intervention in susceptible individuals, targeted nanotherapy potentially provides a fresh perspective that might be better than the current conventional therapies. Independent studies have shown improved drug efficacy by using prohibitin (PHB)-targeted therapy in obese rodents and non-human primates, thus providing a proof of concept that targeted nanotherapy can be a feasible treatment for obesity. This review presents a brief global survey of obesity, its impact on human health, its current treatment and their limitations, and the role of angiogenesis and PHB in the development of obesity. Finally, the role and potential use of nanotechnology coupled with targeted drug delivery in the treatment of obesity are discussed.

Association of abnormal glucose metabolism and insulin resistance in patients with atypical and typical endometrial cancer

This study aimed to detect glucose metabolism indicators and insulin resistance index in patients with endometrial cancer, and to explore the clinical significance and correlation between them. A total of 65 patients with endometrial cancer (52 of typical endometrial and 13 cases of atypical endometrial cancer patients, 27 with diabetes mellitus, and 38 cases without diabetes mellitus) were selected at the People's Hospital of Rizhao from June, 2010 to June, 2016 to serve as the observation group. During the same period, 62 patients with endometrial benign lesions (24 with diabetes mellitus and 38 cases without diabetes mellitus) were selected as the control group. General information including height, body weight, body mass index (BMI), abdominal, waist and hip circumference, and waist-to-hip ratio (WHR) was compared between the two groups. Fasting blood glucose, glycosylated hemoglobin, fasting insulin level (FINS), insulin resistance index (HOMA-IR), follicle estrogen (FSH), luteinizing hormone and estradiol (estrogen) were detected and compared between the two groups. Multivariate logistic regression was used to analyze the risk factors for endometrial cancer. The results showed that there were no significant differences in the height and hip circumference among the typical, atypical and control groups. By contrast, weight, BMI, waist circumference, abdominal circumference and the WHR of the typical group were significantly higher than those of the atypical and control groups (P<0.05). No significant differences were found between the atypical and control groups (P>0.05). Levels of the FINS and HOMA-IR typical group were significantly higher than those in the atypical and control groups, and the incidence of hyperinsulinemia and insulin resistance was significantly higher in the observation than in the control group (P<0.05). Of the patients with diabetes, the levels of FINS, HOMA-IR and estrogen were significantly higher, but the level of FSH was significantly lower in the observation compared to the control group (P<0.05). For patients without diabetes, significant differences in the levels of FINS and HOMA-IR were found between the observation and control groups (P<0.05). There was no significant difference in the levels of FINS and HOMA-IR among endometrial cancer patients with different pathological features (P>0.05). HOMA-IR (OR=1.240), estrogen (OR=1.192) and FSH (OR=1.002) are risk factors for endometrial cancer. The results suggest that hyperinsulinemia and insulin resistance are risk factors of endometrial cancer. Insulin may therefore be involved in the development of endometrial cancer by affecting the level of sex hormones.

Leptin induces CREB-dependent aromatase activation through COX-2 expression in breast cancer cells

Leptin plays a key role in the control of adipocyte formation, as well as in the associated regulation of energy intake and expenditure. The goal of this study was to determine if leptin-induced aromatase enhances estrogen production and induces tumor cell growth stimulation. To this end, breast cancer cells were incubated with leptin in the absence or presence of inhibitor pretreatment, and changes in aromatase and cyclooxygenase-2 (COX-2) expression were evaluated at the mRNA and protein levels. Transient transfection assays were performed to examine the aromatase and COX-2 gene promoter activities and immunoblot analysis was used to examine protein expression. Leptin induced aromatase expression, estradiol production, and promoter activity in breast cancer cells. Protein levels of phospho-STAT3, PKA, Akt, ERK, and JNK were increased by leptin. Leptin also significantly increased cAMP levels, cAMP response element (CRE) activation, and CREB phosphorylation. In addition, leptin induced COX-2 expression, promoter activity, and increased the production of prostaglandin E₂. Finally, a COX-2 inhibitor and aromatase inhibitor suppressed leptin-induced cell proliferation in MCF-7 breast cancer cells. Together, our data show that leptin increased aromatase expression in breast cancer cells, which was correlated with COX-2 upregulation, mediated through CRE activation and cooperation among multiple signaling pathways.

Leptin is overexpressed in the tumor microenvironment of obese patients with estrogen receptor positive breast cancer

The present study aimed to investigate the potential role of leptin in the progression of breast cancer and the associated cell proliferation signalling pathway(s). A total of 44 female patients diagnosed with breast cancer and 24 healthy donors from Ain Shams University Hospitals (Cairo, Egypt) were enrolled in the present study. The present study assessed leptin expression in breast cancer tissues at the gene and protein level using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry. The results demonstrate that the expression of leptin was significantly higher in tissue of breast cancer samples from obese patients than overweight and control samples (P<0.001). ELISA results indicated a significant increase (P<0.001) of leptin expression in obese patients. To investigate whether there is any difference in leptin expression between the peripheral and tumor microenvironment blood of patients with breast cancer, the concentration of leptin was assessed in plasma from both using ELISA assays. The results demonstrated a statistically significant increase in the level of leptin in plasma samples from the tumor microenvironment of obese patients with estrogen receptor positive (ER+) breast cancer, compared with peripheral plasma samples. Furthermore, the leptin gene was overexpressed in obese ER+ breast cancer tissue. RT-qPCR was also performed to assess the expression of genes involved in proliferation pathways including leptin receptor (LEPR), aromatase, mitogen activated protein kinase (MAPK) and signal transducer and activator of transcription-3 (STAT3). A positive association between leptin expression, LEPR, aromatase, MAPK and STAT3 was detected in tissue samples of patients with breast cancer. The current study concluded that leptin may enhance breast cancer progression by inducing the expression of JAK/STAT3, ERK1/2 and estrogen pathways in obese patients breast cancer.

Diabesity: A Polygenic Model of Dietary-Induced Obesity from Ad Libitum Overfeeding of Sprague–Dawley Rats and Its Modulation by Moderate and Marked Dietary Restriction

This study compared the effects of ad libitum (AL) overfeeding and moderate or marked dietary restriction (DR) on the pathogenesis of a metabolic syndrome of diabesity comprised of age-related degenerative diseases and obesity in a outbred stock of Sprague–Dawley (SD) rats [Crl:CD (SD) IGS BR]. SD rats were fed Purina Certified Rodent Diet AL (group 1), DR at 72–79% of AL (group 2), DR at 68–72% of AL (group 3) or DR at 47–48% of AL (group 4) for 106 weeks. Interim necropsies were performed at 13, 26, and 53 weeks, after a 7-day 5-bromo-2-deoxyuridine (BrdU)-filled minipump implantation. Body weights, organ weights, carcass analysis, in-life data including estrous cyclicity, and histopathology were determined. At 6–7 weeks of age SD rats had 6% body fat. AL-feeding resulted in hypertriglyceridemia, hypercholesterolemia, and dietary-induced obesity (DIO) by study week 14, with 25% body fat that progressed to 36–42% body fat by 106 weeks. As early as 14 weeks, key biomarkers developed for spontaneous nephropathy, cardiomyopathy, and degenerative changes in multiple organ systems. Early endocrine disruption was indicated by changes in metabolic and endocrine profiles and the early development and progression of lesions in the pituitary, pancreatic islets, adrenals, thyroids, parathyroids, liver, kidneys, and other tissues. Reproductive senescence was seen by 9 months with declines in estrous cyclicity and pathological changes in the reproductive organs of both sexes fed AL or moderate DR, but not marked DR. The diabesity syndrome in AL-fed, DIO SD rats was readily modulated or prevented by moderate to marked DR. Moderate DR of balanced diets resulted in a better toxicology model by significantly improving survival, controlling adult body weight and obesity, reducing the onset, severity, and morbidity of age-related renal, endocrine, metabolic, and cardiac diseases. Moderate DR feeding reduces study-to-study variability, increases treatment exposure time, and increases the ability to distinguish true treatment effects from spontaneous aging. The structural and metabolic differences between the phenotypes of DIO and DR SD rats indicated changes of polygenic expression over time in this outbred stock. AL-overfeeding of SD rats produces a needed model of DIO and diabesity that needs further study of its patterns of polygenic expression and phenotype.

A polymorphic repeat in the IGF1 promoter influences the risk of endometrial cancer

Due to the lack of high-throughput genetic assays for tandem repeats, there is a paucity of knowledge about the role they may play in disease. A polymorphic CA repeat in the promoter region of the insulin-like growth factor 1 gene (IGF1 has been studied extensively over the past 10 years for association with the risk of developing breast cancer, among other cancers, with variable results. The aim of this study was to determine if this CA repeat is associated with the risk of developing breast cancer and endometrial cancer. Using a case-control design, we analysed the length of this CA repeat in a series of breast cancer and endometrial cancer cases and compared this with a control population. Our results showed an association when both alleles were considered in breast and endometrial cancers (P=0.029 and 0.011, respectively), but this did not pass our corrected threshold for significance due to multiple testing. When the allele lengths were analysed categorically against the most common allele length of 19 CA repeats, an association was observed with the risk of endometrial cancer due to a reduction in the number of long alleles (P=0.013). This was confirmed in an analysis of the long alleles separately for endometrial cancer risk (P=0.0012). Our study found no association between the length of this polymorphic CA repeat and breast cancer risk. The significant association observed between the CA repeat length and the risk of developing endometrial cancer has not been previously reported.

A Bioactivity-Based Method for Screening, Identification of Lipase Inhibitors, and Clarifying the Effects of Processing Time on Lipase Inhibitory Activity of Polygonum Multiflorum

Traditional Chinese medicine (TCM) has been used for the treatment of many complex diseases. However, the bioactive components are always undefined. In this study, a bioactivity-based method was developed and validated to screen lipase inhibitors and evaluate the effects of processing on the lipase inhibitory activity of TCM by ultrahigh performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and fraction collector (UHPLC/Q-TOF-MS-FC). The results showed that both Polygonum multiflorum and processed P. multiflorum extracts had inhibitory effect against lipase with IC50 values of 38.84 μg/mL and 190.6 μg/mL, respectively. Stilbenes, phenolic acid, flavonoids, and anthraquinones were considered to be the potential lipase inhibitors. Eleven potential lipase inhibitors were simultaneously determined by UHPLC. Principal component analysis (PCA) was employed in exploring the effects of processing time on lipase inhibitory activity of P. multiflorum. Compared with conventional methods, a bioactivity-based method could quantitatively analyze lipase inhibitory activity of individual constituent and provide the total lipase inhibitory activity of the samples. The results demonstrated that the activity integrated UHPLC/Q-TOF-MS-FC method was an effective and powerful tool for screening and identifying lipase inhibitors from traditional Chinese medicines.

Pathophysiology of heavy menstrual bleeding

Heavy menstrual bleeding (HMB) is a common gynecological complaint with multiple etiologies and diverse pathophysiological origins. This review discusses HMB with reference to the recently proposed PALM-COEIN classification system for abnormal uterine bleeding, initially describing the endometrial events in normal menstruation followed by discussion of the perturbations of normal endometrial shedding that can result in HMB. Our present understanding of the mechanisms of menstrual bleeding as well as many of the pathological aberrations of HMB is incomplete. Further research into the pathophysiology of HMB is urgently needed, as clear knowledge of the mechanisms of this disorder will provide new therapeutic targets to formulate more effective treatments.

Adiposity and cancer risk: new mechanistic insights from epidemiology

Excess body adiposity, commonly expressed as body mass index (BMI), is a risk factor for many common adult cancers. Over the past decade, epidemiological data have shown that adiposity-cancer risk associations are specific for gender, site, geographical population, histological subtype and molecular phenotype. The biological mechanisms underpinning these associations are incompletely understood but need to take account of the specificities observed in epidemiology to better inform future prevention strategies.

Visceral to total obesity ratio and severe hydronephrosis are independently associated with prolonged pneumoperitoneum operative time in patients undergoing laparoscopic radical nephroureterectomy for upper tract urothelial carcinoma

BACKGROUND

Our aim was to evaluate the effect of visceral obesity and impact of severe hydronephrosis on surgical complexity in patients undergoing laparoscopic radical nephroureterectomy (LRNU).

METHODS

From January 2000 to December 2013, 169 patients underwent radical nephroureterectomy at our institution. We retrospectively reviewed the medical records of 70 patients who underwent LRNU. We measured total fat area (TFA) and visceral fat area (VFA) at the level of the umbilicus using computed tomography. We defined accumulated visceral fat distribution as a VFA/TFA ratio ≥0.45. Ipsilateral hydronephrosis was graded from 0 to 4 by two uro-radiologists blinded to the clinical outcomes.

RESULTS

Among the 70 patients, VFA/TFA ratio was ≥0.45 in 40 patients (57.1%) and 28 (40.0%) had severe hydronephrosis (grade 3 or greater). Patients with a VFA/TFA ratio ≥0.45 had significantly longer pneumoperitoneum and total operation times compared to their counterparts (p = 0.047 and p = 0.002, respectively). Patients with severe hydronephrosis had significantly longer pneumoperitoneum and total operative times compared to their counterparts (p = 0.006 and p = 0.002, respectively). Multivariate logistic regression analysis showed that a high VFA/TFA and severe hydronephrosis were independent predictive factors for prolonged pneumoperitoneum (p = 0.048, HR = 2.90; p = 0.015, HR = 3.82, respectively) and total operative times (p < 0.001, HR = 18.7; p = 0.003, HR = 10.7; respectively). Other pre-clinical factors such as age, gender, BMI, clinical stage, tumor size, location, laterality, degree of perinephric stranding, and surgical procedure did not affect the operation times.

CONCLUSION

The present data indicated that the visceral type of adipose accumulation and presence of severe hydronephrosis could provide preoperative information on the degree of technical difficulty associated with LRNU.

Anthropometry and head and neck cancer:a pooled analysis of cohort data

BACKGROUND

Associations between anthropometry and head and neck cancer (HNC) risk are inconsistent. We aimed to evaluate these associations while minimizing biases found in previous studies.

METHODS

We pooled data from 1,941,300 participants, including 3760 cases, in 20 cohort studies and used multivariable-adjusted Cox proportional hazard regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of anthropometric measures with HNC risk overall and stratified by smoking status.

RESULTS

Greater waist circumference (per 5 cm: HR = 1.04, 95% CI 1.03-1.05, P-value for trend = <0.0001) and waist-to-hip ratio (per 0.1 unit: HR = 1.07, 95% CI 1.05-1.09, P-value for trend = <0.0001), adjusted for body mass index (BMI), were associated with higher risk and did not vary by smoking status (P-value for heterogeneity = 0.85 and 0.44, respectively). Associations with BMI (P-value for interaction = <0.0001) varied by smoking status. Larger BMI was associated with higher HNC risk in never smokers (per 5 kg/m(2): HR = 1.15, 95% CI 1.06-1.24, P-value for trend = 0.0006), but not in former smokers (per 5 kg/m(2): HR = 0.99, 95% CI 0.93-1.06, P-value for trend = 0.79) or current smokers (per 5 kg/m(2): HR = 0.76, 95% CI 0.71-0.82, P-value for trend = <0.0001). Larger hip circumference was not associated with a higher HNC risk. Greater height (per 5 cm) was associated with higher risk of HNC in never and former smokers, but not in current smokers.

CONCLUSIONS

Waist circumference and waist-to-hip ratio were associated positively with HNC risk regardless of smoking status, whereas a positive association with BMI was only found in never smokers.

Impact of obesity on secondary cytoreductive surgery and overall survival in women with recurrent ovarian cancer

OBJECTIVES

Obesity may negatively influence tumor biology in women with epithelial ovarian cancers. To date, only body mass indices (BMI) determined at the time of diagnosis have correlated with clinical outcome. We hypothesized that obesity negatively affects survival throughout the disease course, and sought to determine the prognostic role of BMI at the time of secondary cytoreductive surgery (SCS) for recurrent ovarian cancer.

METHODS

We performed a review of patients undergoing SCS for recurrent epithelial ovarian or peritoneal cancer between 1997 and 2012. We retrospectively reviewed data which were analyzed using Fisher's exact test, Kaplan-Meier survival, and Cox regression analysis. BMI was defined according to the National Institutes of Health's categorizations.

RESULTS

We identified 104 patients; 2 were underweight, 46 were of ideal body weight, 32 were overweight, and 24 were obese. Overall, 90 patients underwent optimal resection and BMI did not correlate with ability to perform optimal SCS (p=0.25). When examining BMI strata (underweight, ideal, overweight, and obese), we observed a statistical trend between increasing BMI and poor outcome; median survival was undetermined (greater than 50 months), 46 months, 38 months, and 34 months, respectively (p=0.04). In a multivariate analysis, BMI was an independent predictor of survival (p=0.02).

CONCLUSIONS

In this cohort of women undergoing SCS for recurrent ovarian cancer, BMI significantly and independently correlated with overall survival. This observation suggests an effect of excess weight on tumor biology and/or response to treatment that is prevalent throughout the disease course.

Infiltrated pre-adipocytes increase prostate cancer metastasis via modulation of the miR-301a/androgen receptor (AR)/TGF-β1/Smad/MMP9 signals

High fat dietary intake may increase the risk of prostate cancer (PCa). Pre-adipocytes, one of the basic components in the tumor microenvironment (TME), are capable of differentiating into adipose tissues and play key roles to affect PCa progression. Here we found the pre-adipocytes could be recruited more easily to PCa than its surrounding normal prostate tissue. In vitro co-culture system also confirmed PCa has a better capacity than normal prostate to recruit pre-adipocytes. The consequences of recruiting more pre-adipocytes may then increase PCa cell invasion. Mechanism dissection revealed infiltrating pre-adipocytes might function through down-regulation of the androgen receptor (AR) via modulation of miR-301a, and then increase PCa cell invasion via induction of TGF-β1/Smad/MMP9 signals. The mouse model with orthotopically xenografted PCa CWR22Rv1 cells with pre-adipocytes also confirmed that infiltrating pre-adipocytes could increase PCa cell invasion via suppressing AR signaling. Together, our results reveal a new mechanism showing pre-adipocytes in the prostate TME can be recruited to PCa to increase PCa metastasis via modulation of the miR-301a/AR/TGF-β1/Smad/MMP9 signals. Targeting this newly identified signaling may help us to better inhibit PCa metastasis.

Proinflammatory cytokines in prostate cancer development and progression promoted by high-fat diet

Background. We aimed to examine whether proinflammatory cytokines participated in prostate cancer (PCa) development and progression promoted by high-fat diet (HFD). Methods. TRAMP (transgenic adenocarcinoma mouse prostate) mice were randomly divided into two groups: normal diet group and HFD group. Mortality rate and tumor formation rate were examined. TRAMP mice were sacrificed and sampled on the 20th, 24th, and 28th week, respectively. Levels of proinflammatory cytokines, including IL-1α, IL-1β, IL-6, and TNF-α, were tested by FlowCytomix. Prostate tissue of TRAMP mice was used for histology study. Results. A total of 13 deaths of TRAMP mice were observed, among which 3 (8.33%) were from the normal diet group and 10 (27.78%) from the HFD group. The mortality rate of TRAMP mice from HFD group was significantly higher than that of normal diet group (P = 0.032). Tumor formation rate at 20th week of age of HFD group was significantly higher than that of normal diet group (P = 0.045). Proinflammatory cytokines levels, including IL-1α, IL-1β, IL-6, and TNF-α, were significantly higher in HFD TRAMP mice. Conclusions. HFD could promote TRAMP mouse PCa development and progression with elevated proinflammatory cytokines levels. Proinflammatory cytokines could contribute to PCa development and progression promoted by HFD.

Long‑term exposure to leptin enhances the growth of prostate cancer cells

Obesity correlates with an increased risk of developing prostate cancer (PCa) and leptin plays an important role in PCa progression. Since leptin is produced by adipocytes, the serum leptin level is higher in obese than in non-obese individuals. However, the effects of leptin remain controversial and unclear. The aim of the present study was to investigate the effect of leptin on PCa cell aggressiveness. Three human PCa cell lines (LNCaP, DU145 and PC-3) were treated with recombinant leptin for 28 days. Cell proliferation, migration, and invasion were estimated using the WST assay, a wound-healing assay, and a BD Matrigel invasion assay, respectively. The mechanism underlying the proliferative effect of leptin was investigated by cell transfections with small interfering RNA (siRNA) against the leptin receptor (ObR) or forkhead box O1 (FOXO1), and by immunocytochemistry. Long-term exposure of PCa cells to leptin enhanced their proliferation, migration and invasion. Leptin increased ObR expression and enhanced Akt phosphorylation constitutively. Leptin also increased the phosphorylation of FOXO1 via PI3K signaling and FOXO1 gene silencing enhanced PCa cell proliferation. Leptin induced the translocation of FOXO1 from the nucleus to the cytoplasm. Furthermore, the PI3K inhibitor, LY294002 suppressed this translocation. These results suggested that leptin regulated the subcellular localization of FOXO1 and induced Akt phosphorylation. Additionally, we revealed that leptin increased the expression of cyclin D1 and decreased the expression of p21 protein. In conclusion, long-term exposure to leptin increased the cell proliferation, migration, and invasion of PCa cells through inactivation of FOXO1. This inactivation resulted from exclusion of FOXO1 from the nucleus and its restriction to the cytoplasm through PI3K/Akt signaling. Our findings contribute to an understanding of the association between obesity and PCa aggressiveness.

Efficacy of Repeated Transrectal Prostate Biopsy in Men Younger Than 50 Years With an Elevated Prostate-Specific Antigen Concentration (>3.0 ng/mL): Risks and Benefits Based on Biopsy Results and Follow-up Status

PURPOSE

Prostate cancer is rare in men younger than 50 years. Digital rectal examination (DRE) and measurement of prostate-specific antigen (PSA) concentrations are standard screening methods for detecting prostate cancer. We retrospectively investigated the risks and benefits of repeated transrectal ultrasonography-guided prostate needle biopsies in relation to the follow-up status of men younger than 50 years with a consistently high PSA concentration (>3.0 ng/mL).

MATERIALS AND METHODS

During the period from January 2000 through February 2013, we reviewed patient's ages, dates of procedures, DRE results, frequencies of biopsies, results of the biopsies, periods of follow-up, PSA concentrations, and prostate volumes in Chonbuk National University Hospital records. We conducted telephone interviews in patients who did not undergo regular follow-up.

RESULTS

The mean age of the patients was 44.7 years, and the mean PSA concentration was 8.59 ng/mL (range, 3.04-131 ng/mL) before biopsy. The PSA concentration was significantly different (p<0.001) between the patients with prostate cancer and those with benign prostatic hyperplasia (BPH). Nineteen patients underwent repeated prostate biopsy; however, in only one patient did the pathologic findings indicate a change from BPH to prostate cancer. We identified several complications after transrectal biopsy through an evaluation of follow-up data.

CONCLUSIONS

All patients with benign prostatic disease based on their first biopsy were shown to have benign disease based on all repeated biopsies (15.83%), except for one patient; however, several complications were noted after biopsy. Therefore, the risks and benefits of repeated biopsy in young patients should be considered because of the low rate of change from benign to malignant disease despite continuously high PSA concentrations (>3.0 ng/mL).

Leptin induces CYP1B1 expression in MCF-7 cells through ligand-independent activation of the ERα pathway

Leptin, a hormone with multiple biological actions, is produced predominantly by adipose tissue. Among its functions, leptin can stimulate tumour cell growth. Oestrogen receptor α (ERα), which plays an essential role in breast cancer development, can be transcriptionally activated in a ligand-independent manner. In this study, we investigated the effect of leptin on CYP1B1 expression and its mechanism in breast cancer cells. Leptin induced CYP1B1 protein, messenger RNA expression and promoter activity in ERα-positive MCF-7 cells but not in ERα-negative MDA-MB-231 cells. Additionally, leptin increased 4-hydroxyoestradiol in MCF-7 cells. Also, ERα knockdown by siRNA significantly blocked the induction of CYP1B1 expression by leptin, indicating that leptin induced CYP1B1 expression via an ERα-dependent mechanism. Transient transfection with CYP1B1 deletion promoter constructs revealed that the oestrogen response element (ERE) plays important role in the up-regulation of CYP1B1 by leptin. Furthermore, leptin stimulated phosphorylation of ERα at serine residues 118 and 167 and increased ERE-luciferase activity, indicating that leptin induced CYP1B1 expression by ERα activation. Finally, we found that leptin activated ERK and Akt signalling pathways, which are upstream kinases related to ERα phosphorylation induced by leptin. Taken together, our results indicate that leptin-induced CYP1B1 expression is mediated by ligand-independent activation of the ERα pathway as a result of the activation of ERK and Akt in MCF-7 cells.

Transcriptional background of beef marbling - novel genes implicated in intramuscular fat deposition

The purpose of this study was to identify novel marbling-related genes by comparison of the global gene expression in semitendinosus muscle of 15-month-old Limousin (LIM), Holstein-Friesian (HF) and Hereford (HER) bulls. Muscle of LIM was lean with low intramuscular fat (IMF) content (0.53%) unlike the marbled muscles of HER and HF characterized by higher amounts of IMF (1.10 and 0.81%, respectively). The comparison of muscle transcriptional profile between marbled and lean beef revealed significant differences in expression of 144 genes, presumably involved in consecutive stages of adipose tissue development, such as preadipocyte proliferation and differentiation, adipocyte maturation, lipid filling and lipid metabolism leading to increased IMF deposition and marbling development. Correlation coefficients and regression analysis for nine of them (gadd45a, pias3, ccrn4l, diras3, pou5f1, hoxa9, atp2a2 and pim1) validated by real-time qPCR confirmed their moderate-high correlation with IMF% and explained up to 70.5% of the total variability in IMF deposition in the bulls.

Leptin promotes human endometrial carcinoma cell proliferation by enhancing aromatase (P450arom) expression and estradiol formation

OBJECTIVE

Leptin, a multifunctional peptide hormone encoded by the obese (ob) gene, plays an important role in modulating lipid metabolism and energy equilibrium. Leptin reportedly acts as a cell growth factor and enhances the proliferation of various tumors. We investigated the effect of leptin on aromatase (P450arom) expression and estradiol (E2) formation in a model of endometrial carcinoma.

STUDY DESIGN

We established a co-culture model of endometrial fibroblasts and the Ishikawa endometrial carcinoma cell line. P450arom mRNA and protein expression were measured with RT-PCR and immunoblotting, respectively, before and after leptin treatment. The effect of leptin on estradiol formation in endometrial carcinoma cells was also detected with a radioimmunological method.

RESULTS

P450arom mRNA expression was increased in co-cultures treated with 100 ng/ml leptin (P<0.01). Estradiol synthesis was induced when androstenedione was added to the culture medium, and significantly higher estradiol concentration was observed in co-cultures treated with 100 ng/ml leptin,

CONCLUSIONS

Leptin is an important component of the microenvironment and stimulates endometrial carcinoma cell proliferation via enhancing P450arom expression and estradiol synthesis.

Alternative dietary fiber sources in companion animal nutrition

The US has a pet population of approximately 70 million dogs and 74 million cats. Humans have developed a strong emotional bond with companion animals. As a consequence, pet owners seek ways to improve health, quality of life and longevity of their pets. Advances in canine and feline nutrition have contributed to improved longevity and well-being. Dietary fibers have gained renewed interest in the pet food industry, due to their important role in affecting laxation and stool quality. More recently, because of increased awareness of the beneficial effects of dietary fibers in health, as well as the popularity of functional foods and holistic and natural diets, alternative and novel carbohydrates have become widespread in human and pet nutrition. Fiber sources from cereal grains, whole grains and fruits have received increasing attention by the pet food industry and pet owners. While limited scientific information is available on the nutritional and nutraceutical properties of alternative fiber sources, studies indicate that corn fiber is an efficacious fiber source for pets, showing no detrimental effects on palatability or nutrient digestibility, while lowering the glycemic response in adult dogs. Fruit fiber and pomaces have good water-binding properties, which may be advantageous in wet pet food production, where a greater water content is required, along with low water activity and a firm texture of the final product. Rice bran is a palatable fiber source for dogs and may be an economical alternative to prebiotic supplementation of pet foods. However, it increases the dietary requirement of taurine in cats. Barley up to 40% in a dry extruded diet is well tolerated by adult dogs. In addition, consumption of complex carbohydrates has shown a protective effect on cardiovascular disease and oxidative stress. Alternative fiber sources are suitable ingredients for pet foods. They have been shown to be nutritionally adequate and to have potential nutraceutical properties.

Hormones of adipose tissue and their biologic role in lung cancer

INTRODUCTION

Adipose tissue secretes numerous bioactive peptides, collectively termed "adipocytokines" or "adipokines". Adipokines act in a paracrine, autocrine, or endocrine manner and regulate several physiological and pathological processes. Increasing evidence indicates that adipokines are implicated also in several malignancies, including lung cancer as well.

AIM

The aim of this study is to summarize data concerning adipokines in lung cancer pathogenesis, prognosis and survival; the role of adipokines in lung cancer cachexia is also examined.

MATERIALS AND METHODS

A systematic literature search was performed in the electronic database of Medline. Several studies and review articles met the inclusion criteria.

RESULTS

Leptin and adiponectin are the best studied adipokines. The majority of the relevant studies has investigated the potential correlations mainly between leptin, adiponectin, and sometimes also resistin, and nutritional status, systemic inflammation of lung cancer or lung cancer cachexia and have also assessed their prognostic significance. Few other studies have studied genetic variations in leptin, leptin receptor and adiponectin genes and their association with lung cancer susceptibility and prognosis. The ongoing list of adipokines associated with lung cancer also includes resistin, chemerin, and visfatin.

CONCLUSIONS

Increasing evidence points to the involvement of certain adipocytokines in lung cancer development, progression and prognosis. No conclusive evidence exists so far with regards to the role of adipocytokines in lung cancer cachexia. Future, longitudinal studies are warranted in order to clarify the role of adipocytokines in lung cancer and also uncover adipocytokines as novel therapeutic targets.

The role of chronic inflammation in obesity-associated cancers

There is a strong relationship between metabolism and immunity, which can become deleterious under conditions of metabolic stress. Obesity, considered a chronic inflammatory disease, is one example of this link. Chronic inflammation is increasingly being recognized as an etiology in several cancers, particularly those of epithelial origin, and therefore a potential link between obesity and cancer. In this review, the connection between the different factors that can lead to the chronic inflammatory state in the obese individual, as well as their effect in tumorigenesis, is addressed. Furthermore, the association between obesity, inflammation, and esophageal, liver, colon, postmenopausal breast, and endometrial cancers is discussed.

Effects of dietary high fat on prostate intraepithelial neoplasia in TRAMP mice

Increased fat intake is known to be a major cause of prostate cancer. In this study, we investigated the effect of dietary high fat on prostate intraepithelial neoplasia using transgenic adenocarcinoma mouse prostate (TRAMP) mice. Six-week-old male TRAMP mice were fed AIN93G (control group, 4.0 kcal/kg, n=6) and AIN93G-HFD (experimental group, 4.8 kcal/kg, n=7) for 10 weeks. Prostate histopathology, urogenital tract (UGT) weight, epididymal white adipose tissue weight, argyrophilic nucleolar organizer regions (AgNORs) counts, and serum leptin levels were examined. AIN93G-HFD fed group showed progressed neoplastic lesions in the prostate (P<0.05) compared to AIN93G fed group. AIN93G-HFD intake resulted in a increase in the weight of UGT (P<0.05) and epididymal white adipose tissue. The number of Ag-NOR positive dots significantly increased in each prostate lobe and final serum leptin levels in AIN93G-HFD fed group were about twice those of AIN93G fed group (P<0.05). Dietary high fat was related to the prostate cancer progression in the early stage of TRAMP mice and increased serum leptin levels, suggesting that the regulation of dietary components could delay the progression of prostate cancer.

Leptin stimulates ovarian cancer cell growth and inhibits apoptosis by increasing cyclin D1 and Mcl-1 expression via the activation of the MEK/ERK1/2 and PI3K/Akt signaling pathways

Obesity is known to be an important risk factor for many types of cancer, such as breast, prostate, liver and endometrial cancer. Recently, epidemiological studies have indicated that obesity correlates with an increased risk of developing ovarian cancer, the most lethal gynecological cancer in developed countries. Leptin is predominantly produced by adipocytes and acts as a growth factor and serum leptin levels positively correlate with the amount of body fat. In this study, we investigated the effects of leptin on the growth of ovarian cancer cells and the underlying mechanism(s) of action. Our results showed that leptin stimulated the growth of the OVCAR-3 ovarian cancer cell line using MTT assay and trypan blue exclusion. Using western blot analysis, we found that leptin enhanced the expression of cyclin D1 and Mcl-1, which are important regulators of cell proliferation and the inhibition of apoptosis. To investigate the signaling pathways that mediate the effects of leptin, cells were treated with leptin plus specific inhibitors of JAK2, PI3K/Akt and MEK/ERK1/2 and analysis of the phosphorylation state of proteins was carried out by western blot assays. We showed that the activation of the MEK/ERK1/2 and PI3K/Akt signaling pathways were involved in the growth-stimulating effect of leptin on ovarian cancer cell growth and the specific inhibitors of PI3K/Akt and MEK/ERK1/2 revealed that these two pathways interacted with each other. Our data demonstrate that leptin upregulates the expression of cyclin D1 and Mcl-1 to stimulate cell growth by activating the PI3K/Akt and MEK/ERK1/2 pathways in ovarian cancer.

Redefining the impact of nutrition on breast cancer incidence: is epigenetics involved?

Breast cancer incidence is rising worldwide with an increase in aggressive neoplasias in young women. Possible factors involved include lifestyle changes, notably diet that is known to make an impact on gene transcription. However, among dietary factors, there is sufficient support for only greater body weight and alcohol consumption whereas numerous studies revealing an impact of specific diets and nutrients on breast cancer risk show conflicting results. Also, little information is available from middle- and low-income countries. The diversity of gene expression profiles found in breast cancers indicates that transcription control is critical for the outcome of the disease. This suggests the need for studies on nutrients that affect epigenetic mechanisms of transcription, such as DNA methylation and post-translational modifications of histones. In the present review, a new examination of the relationship between diet and breast cancer based on transcription control is proposed in light of epidemiological, animal and clinical studies. The mechanisms underlying the impact of diets on breast cancer development and factors that impede reaching clear conclusions are discussed. Understanding the interaction between nutrition and epigenetics (gene expression control via chromatin structure) is critical in light of the influence of diet during early stages of mammary gland development on breast cancer risk, suggesting a persistent effect on gene expression as shown by the influence of certain nutrients on DNA methylation. Successful development of breast cancer prevention strategies will require appropriate models, identification of biological markers for rapid assessment of preventive interventions, and coordinated worldwide research to discern the effects of diet.

Body mass index in relation to oesophageal and oesophagogastric junction adenocarcinomas: a pooled analysis from the International BEACON Consortium

BACKGROUND

Previous studies suggest an association between obesity and oesophageal (OA) and oesophagogastric junction adenocarcinomas (OGJA). However, these studies have been limited in their ability to assess whether the effects of obesity vary by gender or by the presence of gastro-oesophageal reflux (GERD) symptoms.

METHODS

Individual participant data from 12 epidemiological studies (8 North American, 3 European and 1 Australian) comprising 1997 OA cases, 1900 OGJA cases and 11 159 control subjects were pooled. Logistic regression was used to estimate study-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between body mass index (BMI, kg/m(2)) and the risk of OA and OGJA. Random-effects meta-analysis was used to combine these ORs. We also investigated effect modification and synergistic interaction of BMI with GERD symptoms and gender.

RESULTS

The association of OA and OGJA increased directly with increasing BMI (P for trend <0.001). Compared with individuals with a BMI <25, BMI ≥40 was associated with both OA (OR 4.76, 95% CI 2.96-7.66) and OGJA (OR 3.07, 95% CI 1.89-4.99). These associations were similar when stratified by gender and GERD symptoms. There was evidence for synergistic interaction between BMI and GERD symptoms in relation to OA/OGJA risk.

CONCLUSIONS

These data indicate that BMI is directly associated with OA and OGJA risk in both men and women and in those with and without GERD symptoms. Disentangling the relationship between BMI and GERD will be important for understanding preventive efforts for OA and OGJA.

Prenatal Exposure to Nicotine Causes Postnatal Obesity and Altered Perivascular Adipose Tissue Function

OBJECTIVE

Recent epidemiological studies have shown that there is an increased risk of obesity and hypertension in children born to women who smoked during pregnancy. The aim of this study was to examine the effect of fetal and neonatal exposure to nicotine, the major addictive component of cigarette smoke, on postnatal adiposity and blood vessel function.

RESEARCH METHODS AND PROCEDURES

Female Wistar rats were given nicotine or saline (vehicle) during pregnancy and lactation. Postnatal growth was determined in the male offspring from weaning until 26 weeks of age. At 26 weeks of age, fat pad weight and the function of the perivascular adipose tissue (PVAT) in the thoracic aorta and mesenteric arteries were examined.

RESULTS

Exposure to nicotine resulted in increased postnatal body weight and fat pad weight and an increased amount of PVAT in the offspring. Contraction of the aorta induced by phenylephrine was significantly attenuated in the presence of PVAT, whereas this effect was not observed in the aortic rings from the offspring of nicotine-exposed dams. Phenylephrine-induced contraction without PVAT was not different between saline- and nicotine-exposed rats. Transfer of solution incubated with PVAT-intact aorta to PVAT-free aorta induced a marked relaxation response in the rats from saline-exposed dams, but this relaxation response was significantly impaired in the rats from nicotine-exposed dams.

DISCUSSION

Our results showed that prenatal nicotine exposure increased adiposity and caused an alteration in the modulatory function of PVAT on vascular relaxation response, thus providing insight into the mechanisms underlying the increased prevalence of obesity and hypertension in children exposed to cigarette smoke in utero.

Hypertension, obesity and prostate cancer biochemical recurrence after radical prostatectomy

BACKGROUND

The metabolic syndrome (MetS) comprises a constellation of risk factors associated with an increased risk for cardiovascular disease. Components of MetS have emerged as putative risk factors for prostate carcinoma. In this study, we examine the association between three features of the MetS (obesity, hypertension and diabetes) and the risk of biochemical recurrence (BCR) after radical prostatectomy (RP).

METHODS

We examined data from 1428 men in the University of Michigan Prostate Cancer Data Bank who elected to have RP as their primary treatment. We calculated body mass index from patients' weight and height measured at the time of prostate cancer diagnosis. We used the University of Michigan's Electronic Medical Record Search Engine to identify subjects with hypertension and/or diabetes before their prostate cancer diagnosis.

RESULTS

Of 1428 men who underwent RP, 107 (8%) subsequently developed BCR with a median length of follow-up post-surgery of 3.6 years. Obesity and hypertension were each associated with an increased risk of BCR (adjusted hazard ratio (aHR) = 1.37; 95% CI 0.92-2.09 and aHR = 1.51, 95% CI 1.01-2.26), whereas no association was observed between diabetes and BCR (aHR = 0.73; 95% CI 0.40-1.33).

CONCLUSIONS

Obesity and hypertension were each associated with an increased risk for BCR of prostate cancer after RP, independent of age at diagnosis and tumor pathological features. Given the increasing rates of obesity, hypertension and prostate cancer, a better understanding of the relationship between these entities is of significant public health importance. Elucidation of the involved pathogenic mechanisms will be needed to establish causality.