The effect of mesenchymal stromal cells in the microenvironment on cancer development.

Inflammatory signals secreted from the tumor microenvironment are thought to promote tumor growth and survival. It has been reported that stromal cells in the tumor microenvironment have similar characteristics to tumor-associated cells. In addition miRNAs play critical roles in various diseases, including cancer. In this study, we aimed to investigate the effects of co-culture of cancer cells and stromal cells isolated from normal and malignant breast tissue on each other and the possible effects of miRNAs on these interactions. The characterized stromal cells were co-cultured with an MDA-MB-231 cancer cell line. The proliferation capacity of the experimental groups was evaluated using the WST-1 assay. The expression of breast cancer-specific miRNAs and related genes were assessed by real-time PCR. ELISA assay was performed to determine the concentration of some cytokines and chemokines. We found that the microenvironment plays an important role in the development of cancer, confirming the changes in the expression of oncogenic and tumor suppressor miRNA and their target genes after co-culture with malignant stromal cells. As a result of the studies, specific gene expressions of related signaling pathways were detected in correlation with miRNA changes and the effects of tumor microenvironment on tumorigenesis were revealed in detail. miRNAs have been shown to play an important role in cancer development in recent studies. The idea that these small molecules can be used in diagnosis and treatment is becoming stronger day by day. We believe that new treatment approaches involving the tumor microenvironment and using miRNAs as markers are promising.

Haplotype Analysis of Vitamin D Receptor (VDR) Gene in Breast Cancer Patients.

BACKGROUND: The aim of the study was to evaluate the role of well-characterized vitamin D receptor (VDR) gene polymorphisms, BsmI (rs 1544410), ApaI (rs 7975232), TaqI (rs 731236), and FokI (rs 10735810) and their haplotypes in the pathogenesis of breast cancer in Turkish women. METHODS: The subjects consisted of women including 331 breast cancer patients and 345 healthy controls. After conventional DNA isolation genotyping was done by a PCR-RFLP method, haplotype analysis was performed using Haploview 4.2. RESULTS: Haplotype analysis in different combinations revealed that frequencies of Fbt, fbt, bAt, and bt haplotypes are significantly higher in breast cancer patients than controls (χ2 = 6.862, p = 0.0088; χ2 = 4.176, p = 0.041; χ2 = 4.184, p = 0.0408; χ2 = 8.409, p = 0.0037 respectively). However, no statistically significant difference between genotypes of cases and controls were found when analyzed separately. CONCLUSIONS: All these data support the hypothesis that it is crucial to evaluate VDR gene polymorphism by haplotype analysis in order to understand how changes in VDR sequence influence the function of the VDR gene and how this variability affects the risk of breast cancer.

Association of the nibrin gene (NBN) variants with breast cancer.

Nibrin, encoded by the NBN gene, participates in DNA repair. Mutations in the NBN gene lead to Nijemen breakage syndrome, which may result in several types of diseases, particularly susceptibility to cancer, including breast cancer. Polymorphic variants and defective mutations occurring in the NBN gene increase the risk of breast cancer through the double-stranded break repair mechanism. The aim of the present study was to investigate a possible association between breast cancer and NBN genetic variants, NBN 924 T>C, 8360 G>C and 30537 G>C, in women with breast cancer. Locus-specific primers were designed to study 3 genetic variants in DNA samples isolated from peripheral blood samples of 101 women with breast cancer and 115 healthy controls. Subsequently, 3 polymerase chain reaction-restriction fragment length polymorphism methods were performed and the obtained results were statistically analysed. The NBN gene 924 T>C variant was found to be significantly associated with breast cancer (χ2=5.722, P=0.017). There were no statistically significant differences between cases and controls in the NBN gene 8360 G>C variant (χ2=1,125, P=0.570) or the NBN gene 30537 G>C variant (χ2=4.301, P=0.116). In conclusion, the NBN gene 924 T>C variant may be a genetic risk factor for breast cancer development in women with breast cancer.

Effects of resveratrol on ileal smooth muscle reactivity in polymicrobial sepsis model.

OBJECTIVE: To determine the effects of resveratrol on the ileal smooth muscle reactivity in polymicrobial sepsis. MATERIAL AND METHODS: Polimicrobial sepsis was induced by the cecal ligation and perforation (CLP) procedure. Sprague Dawley rats were divided into three groups. Rats in resveratrol group received resveratrol after CLP (100 mg/kg, i.p.). Rats received saline immediately after CLP in the sepsis group. Control group rats underwent sham operation. The rats were sacrificed and the ileum was excised 24 h after the operation. Contractile and relaxant responses in isolated smooth muscle strips (SMS) were determined using an in vitro muscle technique. TNFα and IL-6 levels were measured in blood samples. RESULTS: Contractile responses to carbachol and KCl and relaxant responses to transmural electrical field stimulation (EFS) were significantly decreased in the sepsis group compared with control and resveratrol groups. No significant changes were observed for smooth muscle reactivity in the resveratrol and control groups. Sodium nitroprusside (SNP) or papaverine-induced relaxations were similar in the all groups. Resveratrol treatment supressed increased TNFα and IL-6 levels in blood seen in sepsis group. CONCLUSION: Ileal smooth muscle reactivity was improved after resveratrol treatment in rats with sepsis. The results of the present study indicate that the beneficial effects of resveratrol might be, at least in part, attributed to its effects on non-adrenergic non-cholinergic pathway and/or anti-inflammatory and antioxidant activity.

Investigation of the mechanism of nicotine-induced relaxation in guinea pig gallbladder.

BACKGROUND: Muscular contraction of the gallbladder is the primary determinant of bile delivery into duedonum. Gallbladder filling and emptying are influenced by both inhibitory and excitatory stimuli, and NO plays a key role in normal relaxation. In this study, to determine whether nicotine acts on the gallbladder muscle, the mechanism of its effect on strips of guinea pig gallbladder was studied in vitro. MATERIALS AND METHODS: Guinea pig gallbladder muscle strips were mounted in organ bath with modified Krebs-Henseleit solution and aerated with Carbogen. Tension was measured with isometric force transducers, and muscle relaxation was expressed as percent decrease of precontraction induced by carbachol. RESULTS: Nicotine produced concentration dependent relaxation when preparations were precontracted by carbachol (10(-6) M). Nicotine-induced relaxation was 51.6 +/- 3.2% of phenylephrine contraction and was not affected by guanethidine (10(-5) M), propranolol (10(-6) M), hexamethonium (10(-4) M), indomethacin (10(-5) M), N(w)-nitro L-arginine methyl ester (L-NAME) (3 x 10(-5) M), methylene blue (10(-5) M), glibenclamide (10(-5) M), clotrimazole (10(-6) M), tetraethylammonium (3 x 10(-4) M), or 4-aminopyridine (10(-3) M). Nicotine did not exhibit a calcium antagonizing effect. CONCLUSIONS: From these results, we concluded that nicotine-induced relaxation of the guinea pig gallbladder is not mediated by the release of noradrenaline, nitric oxide (NO), prostaglandins, or a related substance, or by the activation of potassium channels, or by the stimulation of nicotinic cholinoceptors. Further work is needed to determine the cellular mechanism(s) of action by which nicotine acts on gallbladder smooth muscle.