1.Effect of DSS on Bacterial Growth in Gastrointestinal Tract.
Hlinková J1, Svobodová H1, Brachtlová T1, Gardlík R1. Folia Biol (Praha). 2016;62(1):40-46.
Inflammatory bowel disease is an idiopathic autoimmune disorder that is mainly divided into ulcerative colitis and Crohn's disease. Probiotics are known for their beneficial effect and used as a treatment option in different gastrointestinal problems. The aim of our study was to find suitable bacterial vectors for gene therapy of inflammatory bowel disease. Salmonella enterica serovar Typhimurium SL7207 and Escherichia coli Nissle 1917 were investigated as potential vectors. Our results show that the growth of Escherichia coli Nissle 1917 was inhibited in the majority of samples collected from dextran sodium sulphate-treated animals compared with control growth in phosphate-buffered saline. The growth of Salmonella enterica serovar Typhimurium SL7207 in all investigated samples was enhanced or unaffected in comparison with phosphate-buffered saline; however, it did not reach the growth rates of Escherichia coli Nissle 1917. Dextran sodium sulphate treatment had a stimulating effect on the growth of both strains in homogenates of distant small intestine and proximal colon samples.
2.Increased fibrosis and impaired intratumoral accumulation of macromolecules in a murine model of pancreatic cancer co-administered with FGF-2.
Sakai S1, Iwata C1, Tanaka HY2, Cabral H3, Morishita Y1, Miyazono K1, Kano MR4. J Control Release. 2016 Apr 12. pii: S0168-3659(16)30194-8. doi: 10.1016/j.jconrel.2016.04.007. [Epub ahead of print]
Pancreatic cancer is notorious for its poor prognosis. The histopathologic characteristic of pancreatic ductal adenocarcinoma (PDAC), which is the most common type of pancreatic cancer, is fibrosis within tumor tissue. Although fibrosis within tumor tissue is thought to impede drug therapy by interfering with the intratumoral accumulation of anti-tumor drugs, this hypothesis has yet to be proven directly in preclinical models. Here, we evaluated the effect of enhanced fibrosis on intratumoral accumulation of macromolecular drugs by increasing fibrosis in a murine tumor model of subcutaneously xenografted BxPC-3, a human PDAC cell line. When fibroblast growth factor-2 (FGF-2) was co-administered upon BxPC-3 inoculation, stromal fibrotic area was increased and was characterized by augmented murine collagen accumulation compared to inoculation of BxPC-3 alone, which correlated with increased monocyte/macrophage contents in the tumor tissues.
3.Anti-inflammatory effects of novel AP-1 and NF-κB inhibitors in dextran-sulfate-sodium-induced colitis in rats.
El-Salhy M1, Umezawa K2. Int J Mol Med. 2016 Apr 12. doi: 10.3892/ijmm.2016.2560. [Epub ahead of print]
The aim of the present study was to elucidate the anti-inflammatory effects of the two novel anti-inflammatory substances, 3-[(dodecylthiocarbonyl)‑methyl]-glutarimide (DTCM-G) and dehydroxymethylepoxyquinomicin (DHMEQ), on DSS-induced colitis in rats. For this purpose, rats with dextran sulfate sodium (DSS)-induced colitis were randomly divided into 3 groups with 10 animals in each group as follows: i) the control group, which received 0.5 ml of 0.5% carboxymethyl cellulose (CMC; vehicle), ii) rats that received DTCM-G (20 mg/kg body weight in 0.5% CMC; the DTCM-G group), and iii) rats that received DHMEQ (15 mg/kg body weight in 0.5% CMC; the DHMEQ group). The animals were sacrificed after the 5-day treatment period, and tissue samples were taken from their colons and sectioned for histological evaluation. The tissue sections were stained with hematoxylin and eosin, and immunostained for leukocytes, lymphocytes, macrophages/monocytes and mast cells.
4.MicroRNA-17~92 inhibits colorectal cancer progression by targeting angiogenesis.
Ma H1, Pan JS2, Jin LX3, Wu J1, Ren YD3, Chen P1, Xiao C4, Han J5. Cancer Lett. 2016 Apr 11. pii: S0304-3835(16)30242-7. doi: 10.1016/j.canlet.2016.04.011. [Epub ahead of print]
The miR-17~92 microRNA (miRNA) cluster host gene is upregulated in a broad spectrum of human cancers including colorectal cancer (CRC). Previous studies have shown that miR-17~92 promotes tumorigenesis and cancer angiogenesis in some tumor models. However, its role in the initiation and progression of CRC remains unknown. In this study, we found that transgenic mice overexpressing miR-17~92 specifically in epithelial cells of the small and large intestines exhibited decreased tumor size and tumor angiogenesis in azoxymethane and dextran sulfate sodium salt (AOM-DSS)-induced CRC model as compared to their littermates control. Further study showed that miR-17~92 inhibited the progression of CRC via suppressing tumor angiogenesis through targeting multiple tumor angiogenesis-inducing genes, TGFBR2, HIF1α, and VEGFA in vivo and in vitro. Collectively, we demonstrated that miR-17~92 suppressed tumor progression by inhibiting tumor angiogenesis in a genetically engineered mouse model, indicating the presence of cellular context-dependent pro- and anti-cancer effects of miR-17~92.