ABSTRACT: The goal of this study is to investigate transcriptome profiles (RNA-seq) of human embryonic stem cell (hESC)-derived pancreatic organoids with or without metformin treatment at various concentrations.
Project description:Pancreatic cancer (pancreatic ductal adenocarcinoma: PDAC) is one of the most aggressive neoplastic diseases. Metformin use was associated with reduced pancreatic cancer incidence or better survival in diabetics. Metformin has been shown to inhibit PDAC cells survival and growth in vitro and in vivo. However, clinical trials using metformin failed to decrease pancreatic cancer progression in patients, raising important questions about molecular mechanisms that protect tumor cells from the antineoplastic activities of metformin. We confirm that metformin acts through inhibition of mitochondrial complex I, decreasing the NAD+/NADH ratio and that NAD+/NADH homeostasis determines metformin sensitivity in several cancer cell lines. Metabolites that can restore the NAD+/NADH ratio turned PDAC cells resistant to metformin. In addition, metformin treatment of PDAC cell lines induced a compensatory NAMPT expression increasing the pool of cellular NAD+. The NAMPT inhibitor FK866 sensitized PDAC cells to the antiproliferative effects of metformin in vitro and decreased cellular NAD+ pool. Intriguingly, FK866 combined with metformin increased survival in mice bearing KP4 cells xenografts but not in mice with PANC1 xenografts. Transcriptome analysis revealed that the drug combination reactivated genes in the p53 pathway and oxidative stress providing new insights about the mechanisms leading to cancer cell death.
Project description:Control or KD hESC were differentiated into organoids as decribed in Methods. RNA was extracted from individual organoids at day 20 after commencing the STEMdiff™ Cerebral Organoid Kit protocol. Day 0 was designated as the day of transfer of hESC to a 96-well plate for differentiation into embryoid bodies .
Project description:We studied the impact of ZIKA virus infection on DNA methylation in whole organoids, organoid derived astrocytes, neurons neural progeniotors and hESC or iPSC derived astrocytes, neurons, neural progenotor cells
Project description:Full protein measurements from in vitro differentiation of the human embryonic stem cell line HUES8 into pancreatic progenitors (PP) and pancreatic duct-like organoids (PDLOs). Protein intensities were quantified by mass spectrometry analysis from PPs at day 13 and from PDLOs at day 59. Please see related publication “Modelling Plasticity and Dysplasia of Pancreatic Ductal Organoids Derived from Human Pluripotent Stem Cells” for experimental details.
Project description:Reduced cancer incidence has been reported among type II diabetics treated with metformin. Metformin exhibits anti-proliferative and anti-neoplastic effects associated with inhibition of mTORC1, but the mechanisms are poorly understood. We provide the first genome-wide analysis of translational targets of canonical mTOR inhibitors (rapamycin and PP242) and metformin, revealing that metformin controls gene expression at the level of mRNA translation to an extent comparable to that of canonical mTOR inhibitors. Importantly, metformin's anti-proliferative activity can be explained by selective translational suppression of mRNAs encoding cell cycle regulators via the mTORC1/4E-BP pathway. Thus, metformin selectively inhibits mRNA translation of encoded proteins that promote neoplastic proliferation, motivating further studies of this compound and related biguanides in cancer prevention and treatment. MCF7 cells were treated with rapamycin, metformin or PP242 at concentrations that inhibited proliferation to 50% of control. Both cytoplasmic and polysome-associated mRNA was extracted from treatments and a vehicle treated control and probed with microarrays.
Project description:To investigate the effects of imeglimin and metformin on islet cells in db/db mice, we isolated pancreatic islets from db/db mice treated with/without imeglimin and metformin or db/+ mice.