Mahmoud A. Alfaqih

The current evidence on statin use and prostate cancer prevention: are we there yet?

An increasing amount of data supports an inverse association between statin use and cancer risk. The findings for prostate cancer, particularly advanced disease, are the most promising of all cancers studied. Use of these agents seems to also be associated with improved prostate- cancer-specific survival, particularly in men undergoing radiotherapy, suggesting usefulness of statins in secondary and tertiary prevention. Some study results might be influenced by increased PSA screening and health-conscious behaviour in statin users but these factors are unlikely to completely account for observed beneficial effects. The epidemiological evidence is supported by preclinical studies that show that statins directly inhibit prostate cancer development and progression in cell-based and animal-based models. The antineoplastic effect of statins might arise from a number of cholesterol-mediated and non-cholesterol-mediated mechanisms that affect pathways essential for cancer formation and progression. Understanding these mechanisms is instrumental in drug discovery research for the development of future prostate cancer therapeutics, as well as in designing clinical trials to test a role for statins in prostate cancer prevention. Currently, sufficient data are lacking to support the use of statins for the primary prevention of prostate cancer and further research is clearly warranted. Secondary and tertiary prevention trials in men who have been diagnosed with prostate cancer might soon be performed.

CYP27A1 Loss Dysregulates Cholesterol Homeostasis in Prostate Cancer

In this study, we used a bioinformatic approach to identify genes whose expression is dysregulated in human prostate cancers. One of the most dramatically downregulated genes identified encodes CYP27A1, an enzyme involved in regulating cellular cholesterol homeostasis. Importantly, lower CYP27A1 transcript levels were associated with shorter disease-free survival and higher tumor grade. Loss of CYP27A1 in prostate cancer was confirmed at the protein level by immunostaining for CYP27A1 in annotated tissue microarrays. Restoration of CYP27A1 expression in cells where its gene was silenced attenuated their growth in vitro and in tumor xenografts. Studies performed in vitro revealed that treatment of prostate cancer cells with 27-hydroxycholesterol (27HC), an enzymatic product of CYP27A1, reduced cellular cholesterol content in prostate cancer cell lines by inhibiting the activation of sterol regulatory-element binding protein 2 and downregulating low-density lipoprotein receptor expression. Our findings suggest that CYP27A1 is a critical cellular cholesterol sensor in prostate cells and that dysregulation of the CYP27A1/27HC axis contributes significantly to prostate cancer pathogenesis. Cancer Res; 77(7); 1662-73. ©2017 AACR.

Evidence for Feedback Regulation Following Cholesterol Lowering Therapy in a Prostate Cancer Xenograft Model

Epidemiologic data suggest cholesterol‐lowering drugs may prevent the progression of prostate cancer, but not the incidence of the disease. However, the association of combination therapy in cholesterol reduction on prostate or any cancer is unclear. In this study, we compared the effects of the cholesterol lowering drugs simvastatin and ezetimibe alone or in combination on the growth of LAPC‐4 prostate cancer in vivo xenografts.

The Bidirectional Relationship between Diabetes and Depression: A Literature Review

Diabetes is a major public health problem worldwide. Depression is a serious mental condition that decreases mental and physical functioning and reduces the quality of life. Several lines of evidence suggest a bidirectional relationship between diabetes and depression: diabetes patients are twice as likely to experience depression than nondiabetic individuals. In contrast, depression increases the risk of diabetes and interferes with its daily self-management. Diabetes patients with depression have poor glycemic control, reduced quality of life, and an increased risk of diabetes complications, consequently having an increased mortality rate. Conflicting evidence exists on the potential role of factors that may account for or modulate the relationship between diabetes and depression. Therefore, this review aims to highlight the most notable body of literature that dissects the various facets of the bidirectional relationship between diabetes and depression. A focused discussion of the proposed mechanisms underlying this relationship is also provided. We systematically reviewed the relevant literature in the PubMed database, using the keywords “Diabetes AND Depression”. After exclusion of duplicate and irrelevant material, literature eligible for inclusion in this review was based on meta-analysis studies, clinical trials with large sample sizes (n≥1,000), randomized clinical trials, and comprehensive national and cross-country clinical studies. The evidence we present in this review supports the pressing need for long, outcome-oriented, randomized clinical trials to determine whether the identification and treatment of patients with these comorbid conditions will improve their medical outcomes and quality of life.

Lower Levels of Serum Adiponectin and the T Allele of rs1501299 of the ADIPOQ Gene Are Protective against Polycystic Ovarian Syndrome in Jordan

Background Polycystic ovary syndrome (PCOS) is a common reproductive disorder. Obesity, which is linked with lower adiponectin levels, increases a womans risk of developing PCOS; however, the association between adiponectin and PCOS is controversial. Adiponectin levels could be affected by single nucleotide polymorphisms (SNPs) in the ADIPOQ gene. This study aimed to test the relationship between serum adiponectin and PCOS in Jordan and the association between the rs2241766, rs1501299, and rs266729 SNPs in the ADIPOQ gene and PCOS. Methods One hundred and fifty-four women with PCOS and 149 age- and body mass index–matched normally menstruating controls were recruited. Serum adiponectin levels were measured using enzyme-linked immunosorbent assay. Genotyping was performed using polymerase chain reaction–restriction fragment length polymorphism analysis. Results Serum adiponectin levels were significantly lower (P=0.0064) in PCOS women and rs1501299 (+276 G/T) genotype distributions were significantly different (P=0.01) between them and normally menstruating women. Multivariate analysis revealed that adiponectin levels remained significantly lower in PCOS women (P=0.001; odds ratio [OR], 0.9; 95% confidence interval [CI], 0.84–0.96). The GT genotype of rs1501299 increased the risk of PCOS (P<0.001; OR, 5.46; 95% CI, 2.42–12.33) and increased the risk of PCOS by three-fold (P<0.001; OR, 3.00; 95% CI, 1.36–6.60) relative to the TT genotype. The GG genotype increased the risk of PCOS as well (P<0.001; OR, 3:00; 95% CI, 1.36–6.60). Conclusion PCOS is associated with lower serum adiponectin levels independent of age and body mass index. The T allele of the rs1501299 (+276 G/T) SNP of the ADIPOQ gene protects against PCOS.

Serum Branched Chain Amino Acids Are Associated with Type 2 Diabetes Mellitus in Jordan

Background Diabetes mellitus is a global public health problem that is caused by the lack of insulin secretion (type 1) or resistance to its action (type 2). A low insulin-to-glucagon ratio predicts an increase in the serum levels of branched chain amino acids, a feature confirmed in several populations. This relationship has not been assessed in Jordan. The objective of this study was to investigate the association between serum branched chain amino acids and type 2 diabetes mellitus in patients in Jordan. Methods Two hundred type 2 diabetes mellitus patients and an additional 200 non-diabetic controls were recruited. Age, body mass index, and waist circumference of the subjects were recorded. Branched chain amino acid, total cholesterol, and triglyceride levels were measured from the collected serum samples. Results Serum branched chain amino acid levels were significantly higher in type 2 diabetes mellitus patients than in non-diabetes individuals (P<0.0001). In binomial regression analysis, serum branched chain amino acid levels remained significantly associated with diabetes mellitus and increased its risk (odds ratio, 1.004; 95% confidence interval, 1.001–1.006; P=0.003). Conclusion Type 2 diabetes mellitus is associated with higher branched chain amino acid levels in Jordan independent of age, sex, body mass index, waist circumference, and total serum cholesterol and serum triglyceride levels.

The Association between Epidermal Growth Factor Receptor (EGFR) Gene Polymorphisms and Lung Cancer Risk

Lung cancer is the leading cause of cancer death globally. The epidermal growth factor receptor (EGFR) plays an important role in cell proliferation and signaling. In this study, we examined the association between EGFR gene polymorphisms and lung cancer risk among the Jordanian population. A total of 129 patients with primary lung cancer and 129 matched healthy controls were recruited into this study. EGFR rs712829, rs712830, rs2072454, and rs11543848 single nucleotide polymorphisms (SNPs) were genotyped to test for their association with lung cancer risk. A significant association was observed between the rs712829 SNP and lung cancer risk (p < 0.05) where the GG + GT genotypes were higher in lung cancer patients when compared to controls. In addition, no association was detected between rs712830, rs2072454, and rs11543848 SNPs and lung cancer risk. When patients were stratified according to the lung cancer type, a significant association was detected between both rs712829 and rs2072454 and adenocarcinoma lung cancer (p < 0.05). Haplotype analysis of all four SNPs showed a significant association between the TCCG haplotype and both lung cancer and the adenocarcinoma subtype (p < 0.001). In conclusion, EGFR rs712829, rs2072454 SNPs, and TCCG haplotypes are associated with a risk of lung cancer among Jordanians. Since genetic associations are affected by the genetic background of populations, more studies in other Arab populations are required to confirm the present findings.

Phenelzine reduces the oxidative damage induced by peroxynitrite in plasma lipids and proteins

Abstract Peroxynitrite is a reactive nitrogen species produced in the intravascular compartment from superoxide anion and nitric oxide. Peroxynitrite destroys blood plasma proteins and membranes of red blood cells and of platelets. This explains why excessive production of peroxynitrite contributes to diseases and to ageing. Therapeutics that antagonize peroxynitrite may delay ageing and the progression of disease. We developed an in vitro assay that allows the investigation of the oxidative damage caused by peroxynitrite in the intravascular compartment. This assay correlates the damage with the rate of formation of protein carbonyl groups, 3-nitrotyrosine (3-NT) and thiobarbituric acid reactive substances. Using this assay, we evaluated the ability of phenelzine, a scavenger of reactive aldehydes, to antagonize the effects of peroxynitrite. Herein, we showed that phenelzine significantly decreased the lipid peroxidative damage caused by peroxynitirite in blood plasma and platelets. Moreover, it inhibited carbonyl group and 3-NT formation in blood plasma and platelet proteins.

Glucagon-like peptide-1 exerts anti-inflammatory effects on mouse colon smooth muscle cells through the cyclic adenosine monophosphate/nuclear factor-κB pathway in vitro

Background Intestinal smooth muscle cells (SMCs) undergo substantial morphological, phenotypic, and contractile changes during inflammatory bowel disease (IBD). SMCs act as a source and target for different inflammatory mediators, however their role in IBD pathogenesis is usually overlooked. Glucagon-like peptide-1 (GLP-1) is an incretin hormone reported to exert multiple anti-inflammatory effects in different tissues including the gastrointestinal tract through various mechanisms. Aim The aim of this research is to explore the effect of GLP-1 analog exendin-4 on the expression and secretion of inflammatory markers from mouse colon smooth muscle cells (CSMCs) after stimulation with lipopolysaccharide (LPS). Materials and methods Freshly isolated CSMCs from male BALB/c mice were cultured in DMEM and treated with vehicle, LPS (1 μg/mL), LPS+exendin-4 (50 nM), or LPS+exendin-4 (100 nM) for 24 h. Expression of inflammatory cytokines was then evaluated by antibody array membrane. Results CSMCs showed basal expression of several cytokines which was enhanced with the induction of inflammation by LPS. However, exendin-4 (50 and 100 nM) significantly (p<0.05) reduced the expression of multiple cytokines including tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), T cell activation gene-3 (TCA-3), stromal cell-derived factor-1 (SDF-1), and macrophage colony stimulating factor (M-CSF). To confirm these results, expression of these cytokines was further assessed by enzyme-linked immunosorbent assay and real-time polymerase chain reaction and similar results were also observed. Moreover, secretion of TNF-α and IL1-α into the conditioned media was significantly downregulated by exendin-4 when compared to LPS-treated cells. Furthermore, LPS increased NF-κB phosphorylation, while exendin-4 significantly reduced levels of NF-κB phosphorylation. Conclusion These data indicate that GLP-1 analogs can exert significant anti-inflammatory effects on CSMCs and can potentially be used as an adjunct treatment for inflammatory bowel conditions.

Validation of the Survival Benefits of Metformin in Middle Eastern Patients With Type II Diabetes Mellitus and Colorectal Cancer

Purpose Epidemiologic data from several populations suggest that metformin may decrease cancer risk and mortality in patients with colorectal cancer (CRC) and type II diabetes mellitus (DM). Although type II DM and CRC are major health problems in the Middle East, no investigations have been performed to test the effect metformin has on the outcome of patients with type II DM and CRC who are also treated with metformin. Materials and Methods We retrospectively reviewed the medical records of 1,902 patients diagnosed with CRC at King Hussein Cancer Center between January 2004 and December 2012, and identified 349 patients (18%) with type II DM; we censored the data of 28 patients because their antidiabetic medications were unknown. We then categorized these 321 patients into two groups: 192 patients treated with metformin (group A) and 129 patients treated with other antidiabetic medications (group B). Results Group A patients had significantly longer overall survival (89 months; 95% CI, 66 to 112 months) and progression-free survival (47 months; 95% CI, 15 to 79 months) than group B patients (overall survival: 36 months; 95% CI, 24 to 48 months; P ≤ .001; progression-free survival: 21 months; 95% CI, 13 to 29 months; P = .016). After adjustment for age, sex, body mass index, aspirin use, anticholesterol treatment, and CRC stage, group A patients had a 40% reduction in mortality (hazard ratio, 0.58; 95% CI, 0.4% to 0.85%; P = .005). Conclusion Our results support findings from other populations that patients with diabetes and CRC who are also treated with metformin have better outcomes than those treated with other antidiabetic medications.