Small intestinal development in suckling rats after enteral obestatin administration

This study investigated the effect of enteral administration of obestatin on the development of small intestine, as well as oxidative stress markers and trancriptomic profile of gastrointestinal genes. Suckling rats were assigned to 3 groups treated with: C-saline solution; OL-obestatin (125 nmol/kg BW); OH-obestatin (250 nmol/kg BW) administered twice daily, from the 14th to the 21st day of life. Enteral administration of obestatin in both studied doses had no effect neither on the body weight of animals nor the BMI calculated in the day of euthanasia. Compared to the control group (C), treatment with obestatin resulted in significant changes in the histometry of the small intestinal wall as well as intestinal epithelial cell remodeling. The observed changes and their possible implications for intestinal development were dependent on the dosage of peptide. The enteral administration of high dose (OH) of obestatin significantly decreased its expression in the stomach and increased markers of oxidative stress. The gene profile revealed MAPK3 (mitogen-activated protein kinase-3) as the key regulator gene for obestatin action in the gastrointestinal track. In conclusion, we have showed that enteral administration of obestatin influences the gut mucosa remodeling. It is also suggested that the administration of high dose (OH) has inhibitory effect on the intestinal maturation of suckling rats

Pituitary tumours — a large retrospective single-centre study of over 2300 cases. Experience of a tertiary reference centre

Introduction: Pituitary adenomas (PAs), also known as a pituitary neuroendocrine tumours (PitNET), are usually benign tumours of the anterior lobe of the pituitary gland and account for the third most common intracranial neoplasm. The most common type of pituitary adenoma is lactotroph adenoma, in which dopamine agonists are the first-line treatment. Nevertheless, in selected cases surgery or even radiotherapy may be required. In the current study, we aimed to analyse all patients who underwent surgery due to intrasellar mass in order to evaluate frequency of particular pituitary tumours, clinical diagnosis, and pathology findings. Material and methods: We retrospectively analysed all cases of patients consecutively operated due to intrasellar mass between 1st January 2010 and 31st December 2018 at the Department of Neurosurgery, Military Institute of Medicine in Warsaw, Poland. Results: Our database included 2348 cases: 1390 women (59.2%) and 958 men (40.8%). The mean age for women was 48.4 years (SD ± 15.72; median 49) and for men 50.9 years (SD ± 14.94; median 53). In our cohort we found: 869 gonadotroph and null cell adenomas, 751 somatotroph and mammosomatotroph adenomas, 386 corticotroph adenomas, 71 plurihormonal adenomas, 59 craniopharyngiomas, 44 lactotroph adenomas, 18 purely thyrotroph adenomas, and other rare cases of pituitary tumours including one pituitary carcinoma metastasising to the liver (corticotroph origin). Conclusions: We provide a comprehensive analysis of both clinical and pathological findings of the largest cohort of patients operated on for pituitary adenomas in one tertiary reference centre. To the best of our knowledge, this is the largest up-to-date published analysis in our country.

Prolonged idasanutlin (RG7388) treatment leads to the generation of p53-mutated cells

The protein p53 protects the organism against carcinogenic events by the induction of cell cycle arrest and DNA repair program upon DNA damage. Virtually all cancers inactivate p53 either by mutations/deletions of the TP53 gene or by boosting negative regulation of p53 activity. The overexpression of MDM2 protein is one of the most common mechanisms utilized by p53wt cancers to keep p53 inactive. Inhibition of MDM2 action by its antagonists has proved its anticancer potential in vitro and is now tested in clinical trials. However, the prolonged treatment of p53wt cells with MDM2 antagonists leads to the development of secondary resistance, as shown first for Nutlin-3a, and later for three other small molecules. In the present study, we show that secondary resistance occurs also after treatment of p53wt cells with idasanutlin (RG7388, RO5503781), which is the only MDM2 antagonist that has passed phase II and entered phase III clinical trials, so far. Idasanutlin strongly activates p53, as evidenced by the induction of p21 expression and potent cell cycle arrest in all the three cell lines tested, i.e., MCF-7, U-2 OS, and SJSA-1. Notably, apoptosis was induced only in SJSA-1 cells, while MCF-7 and U-2 OS cells were able to restore the proliferation upon the removal of idasanutlin. Moreover, idasanutlin-treated U-2 OS cells could be cultured for long time periods in the presence of the drug. This prolonged treatment led to the generation of p53-mutated resistant cell populations. This resistance was generated de novo, as evidenced by the utilization of monoclonal U-2 OS subpopulations. Thus, although idasanutlin presents much improved activities compared to its precursor, it displays the similar weaknesses, which are limited elimination of cancer cells and the generation of p53-mutated drug-resistant subpopulations

Decitabine, a DNA-demethylating agent, promotes differentiation via NOTCH1 signaling and alters immune-related pathways in muscle-invasive bladder cancer

Aberrant DNA methylation observed in cancer can provide survival benefits to cells by silencing genes essential for anti-tumor activity. DNA-demethylating agents such as Decitabine (DAC)/Azacitidine (AZA) activate otherwise silenced tumor suppressor genes, alter immune response and epigenetically reprogram tumor cells. In this study, we show that non-cytotoxic nanomolar DAC concentrations modify the bladder cancer transcriptome to activate NOTCH1 at the mRNA and protein level, increase double-stranded RNA sensors and CK5-dependent differentiation. Importantly, DAC treatment increases ICN1 expression (the active intracellular domain of NOTCH1) significantly inhibiting cell proliferation and causing changes in cell size inducing morphological alterations reminiscent of senescence. These changes were not associated with β-galactosidase activity or increased p16 levels, but instead were associated with substantial IL-6 release. Increased IL-6 release was observed in both DAC-treated and ICN1 overexpressing cells as compared to control cells. Exogenous IL-6 expression was associated with a similar enlarged cell morphology that was rescued by the addition of a monoclonal antibody against IL-6. Treatment with DAC, overexpression with ICN1 or addition of exogenous IL-6 showed CK5 reduction, a surrogate marker of differentiation. Overall this study suggests that in MIBC cells, DNA hypomethylation increases NOTCH1 expression and IL-6 release to induce CK5-related differentiation.Fil: Ramakrishnan, Swathi. Roswell Park Cancer Institute; Estados UnidosFil: Hu, Qiang. Roswell Park Cancer Institute; Estados UnidosFil: Krishnan, Nithya. Roswell Park Cancer Institute; Estados UnidosFil: Wang, Dan. Roswell Park Cancer Institute; Estados UnidosFil: Smit, Evelyn. Roswell Park Cancer Institute; Estados UnidosFil: Granger, Victoria. Roswell Park Cancer Institute; Estados UnidosFil: Rak, Monika. Jagiellonian University; PoloniaFil: Attwood, Kristopher. Roswell Park Cancer Institute; Estados UnidosFil: Johnson, Candace. Roswell Park Cancer Institute; Estados UnidosFil: Morrison, Carl. Roswell Park Cancer Institute; Estados UnidosFil: Pili, Roberto. Indiana University; Estados UnidosFil: Chatta, Gurkamal. Roswell Park Cancer Institute; Estados UnidosFil: Guru, Khurshid. Roswell Park Cancer Institute; Estados UnidosFil: Gueron, Geraldine. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: McNally, Lacey. University of Louisville; Estados UnidosFil: Wang, Jianmin. Roswell Park Cancer Institute; Estados UnidosFil: Woloszynska-Read, Anna. Roswell Park Cancer Institute; Estados Unido

New cationic polyprenyl derivative proposed as a lipofecting agent

Cationic linear poly-cis-isoprenoid prepared from natural plant polyprenol in a mixture with dioleyl phosphatidylethanolamine was found to be an effective lipofection agent for eukaryotic cells. The transfecting activity is related to the poly-cis structure of the polyprenyl chain