A novel model of urinary tract differentiation, tissue regeneration, and disease: reprogramming human prostate and bladder cells into induced pluripotent stem cells

Background: Primary culture and animal and cell-line models of prostate and bladder development have limitations in describing human biology, and novel strategies that describe the full spectrum of differentiation from foetal through to ageing tissue are required. Recent advances in biology demonstrate that direct reprogramming of somatic cells into pluripotent embryonic stem cell (ESC)-like cells is possible. These cells, termed induced pluripotent stem cells (iPSCs), could theoretically generate adult prostate and bladder tissue, providing an alternative strategy to study differentiation. Objective: To generate human iPSCs derived from normal, ageing, human prostate (Pro-iPSC), and urinary tract (UT-iPSC) tissue and to assess their capacity for lineage-directed differentiation. Design, setting, and participants: Prostate and urinary tract stroma were transduced with POU class 5 homeobox 1 (POU5F1; formerly OCT4), SRY (sex determining region Y)-box 2 (SOX2), Kruppel-like factor 4 (gut) (KLF4), and v-myc myelocytomatosis viral oncogene homolog (avian) (MYC, formerly C-MYC) genes to generate iPSCs. Outcome measurements and statistical analysis: The potential for differentiation into prostate and bladder lineages was compared with classical skin-derived iPSCs. The student t test was used. Results and limitations: Successful reprogramming of prostate tissue into Pro-iPSCs and bladder and ureter into UT-iPSCs was demonstrated by characteristic ESC morphology, marker expression, and functional pluripotency in generating all three germ-layer lineages. In contrast to conventional skin-derived iPSCs, Pro-iPSCs showed a vastly increased ability to generate prostate epithelial-specific differentiation, as characterised by androgen receptor and prostate-specific antigen induction. Similarly, UT-iPSCs were shown to be more efficient than skin-derived iPSCs in undergoing bladder differentiation as demonstrated by expression of urothelial-specific markers: uroplakins, claudins, and cytokeratin; and stromal smooth muscle markers: α-smooth-muscle actin, calponin, and desmin. These disparities are likely to represent epigenetic differences between individual iPSC lines and highlight the importance of organ-specific iPSCs for tissue-specific studies. Conclusions: IPSCs provide an exciting new model to characterise mechanisms regulating prostate and bladder differentiation and to develop novel approaches to disease modelling. Regeneration of bladder cells also provides an exceptional opportunity for translational tissue engineering

The sugarcane signal transduction (SUCAST) catalogue: prospecting signal transduction in sugarcane

EST sequencing has enabled the discovery of many new genes in a vast array of organisms, and the utility of this approach to the scientific community is greatly increased by the establishment of fully annotated databases. The present study aimed to identify sugarcane ESTs sequenced in the sugarcane expressed sequence tag (SUCEST) project (<A HREF="http://sucest.lad.ic.unicamp.br/">http://sucest.lad.ic.unicamp.br</A>) that corresponded to signal transduction components. We also produced a sugarcane signal transduction (SUCAST) catalogue (<A HREF="http://sucest.lad.ic.unicamp.br/private/mining-reports/QG/QG-mining.htm">http://sucest.lad.ic.unicamp.br/private/mining-reports/QG/QG-mining.htm</A>) that covered the main categories and pathways. Expressed sequence tags (ESTs) encoding enzymes for hormone (gibberellins, ethylene, auxins, abscisic acid and jasmonic acid) biosynthetic pathways were found and tissue specificity was inferred from their relative frequency of occurrence in the different libraries. Whenever possible, transducers of hormones and plant peptide signaling were catalogued to the respective pathway. Over 100 receptors were found in sugarcane, which contains a large family of Ser/Thr kinase receptors and also photoreceptors, histidine kinase receptors and their response regulators. G-protein and small GTPases were analyzed and compared to known members of these families found in mammalian and plant systems. Major kinase and phosphatase pathways were mapped, with special attention being given to the MAP kinase and the inositol pathway, both of which are well known in plants.<br>O sequenciamento de ESTs (etiquetas de sequencias transcritas) tem possibilitado a descoberta de muitos novos genes em uma ampla variedade de organismos. Um aumento do aproveitamento desta informação pela comunidade científica tem sido possível graças ao desenvolvimento de base de dados contendo seqüências completamente anotadas. O trabalho aqui relatado teve como objetivo a identificação de ESTs de cana de açúcar seqüenciadas através do projeto SUCEST (<A HREF="http://sucest.lad.ic.%20unicamp.br/">http://sucest.lad.ic. unicamp.br</A>) que codificam para proteínas envolvidas em mecanismos de transdução de sinal. Nós também preparamos um catálogo dos componentes de transdução de sinal da cana de açúcar (SUCAST) englobando as principais categorias e vias conhecidas (<A HREF="http://sucest.lad.ic.unicamp.%20br/private/mining-reports/QG/QG-mining.htm">http://sucest.lad.ic.unicamp. br/private/mining-reports/QG/QG-mining.htm</A>). ESTs codificadoras de enzimas envolvidas nas rotas de biossíntese de hormônios (giberelinas, etileno, auxinas, ácido abscíssico, ácido jasmônico) foram encontradas e sua expressão específica nos tecidos foi inferida a partir de seu enriquecimento nas diferentes bibliotecas. Quando possível, transmissores do sinal hormonal e da resposta a peptídeos produzidos pela planta foram associados a suas respectivas vias. Mais de 100 receptores foram encontrados na cana de açúcar, entre os quais uma grande família de receptores Ser/Thr quinase e também de fotoreceptores, receptores do tipo histidina quinase e seus respectivos reguladores da resposta. Proteínas G e GTPases pequenas foram também analisadas e comparadas com membros destas famílias já conhecidos em mamíferos e plantas. As vias principais que envolvem a participação de proteínas quinases e fosfatases foram mapeadas, em especial as vias da quinase MAP quinase e do inositol que são bem estudadas em plantas

Biallelic TET2 mutations confer sensitivity to 5 '-azacitidine in acute myeloid leukemia

Precision medicine can significantly improve outcomes for patients with cancer, but implementation requires comprehensive characterization of tumor cells to identify therapeutically exploitable vulnerabilities. Here, we describe somatic biallelic TET2 mutations in an elderly patient with acute myeloid leukemia (AML) that was chemoresistant to anthracycline and cytarabine but acutely sensitive to 5 '-azacitidine (5 '-Aza) hypomethylating monotherapy, resulting in long-term morphological remission. Given the role of TET2 as a regulator of genomic methylation, we hypothesized that mutant TET2 allele dosage affects response to 5 '-Aza. Using an isogenic cell model system and an orthotopic mouse xenograft, we demonstrate that biallelic TET2 mutations confer sensitivity to 5 '-Aza compared with cells with monoallelic mutations. Our data argue in favor of using hypomethylating agents for chemoresistant disease or as first-line therapy in patients with biallelic TET2-mutated AML and demonstrate the importance of considering mutant allele dosage in the implementation of precision medicine for patients with cancer