Regenerating Life

Stem cells, which are ‘immortal’ cells that divide indefinitely and produce many different cell types, are central to how our body develops and maintains itself. Embryonic stem cells can give rise to all cell types in the body, and there has been lots of interest since their discovery in the 1980s in using such cells to generate new tissues or organs to replace diseased or faulty ones. More recently has come the discovery of induced pluripotent stem cells, which are normal skin cells taken from a person and genetically modified or tweaked chemically to give them stem cell properties. There is now hope that both of these types of stem cells might be used in ‘regenerative’ medicine, for instance in producing pancreatic cells that secrete insulin which could be used to treat diabetes. Perhaps the most remarkable breakthrough in recent years has been the discovery that stem cells introduced into a 3D matrix that is infused with chemicals that stimulate the development of particular cell types, can spontaneously form ‘organoids’, which have many of the cell types and even structural features of human organs such as hearts, kidneys, intestines, and even eyes and brains. Organoids make it possible to study how human organs develop but also this area of science raises many ethical issues. For instance, currently human brain organoids can only grow to the size of an embryonic brain, but if in the future they could be induced to grow to adult brain size, could they develop feelings and thoughts?

Effects of Diesel Exhaust Particles on Mouse Gastric Stem Cells

Stem cells have attracted many scientists because of their unique properties and therapeutic applications. However, very little is known on the environmental toxins that could affect their biological features. This study focuses on the consequences of the exposure of a cell line representative of the mouse gastric stem/progenitor (mGS) cells to diesel exhaust particles (DEPs). These immortal cells were cultured using routine protocols. The DEPs were added to the culture media at 1, 10, and 100 µg/mL for 1 to 72 h. The cells were assayed for their viability, migration, oxidative stress, and the expression of genes specific for cell proliferation, pluripotency, and death. DEPs induced a reduction in the metabolic activity of mGS cells, only at a high concentration of 100 µg/mL. However, no significant effects were detected on cell migration, oxidative stress markers (glutathione and thiobarbituric acid reactive substances), and cell death related proteins/genes. Interestingly, these findings were associated with down-regulation of Notch 2 and 3 and Bmi-1 proteins and activation of STAT3 involved in the regulation of the fate of stem cells. In conclusion, this study demonstrates that mGS cells have some resistance to oxidative stress and apoptosis when exposed to DEPs at the expense of their stemness.

The Role of miRNA and Related Pathways in Pathophysiology of Uterine Fibroids—From Bench to Bedside

Uterine fibroids (UFs) are the most common benign tumors of the female genital tract. Their prevalence usually is estimated at 30–40%, but may reach up to 70–80% in predisposed groups of women. UFs may cause various clinical issues which might constitute the major reason of the overall deterioration of the quality of life. The mechanisms leading to UFs formation and growth still remain poorly understood. The transformation of smooth muscle cells of the uterus into abnormal, immortal cells, capable of clonal division, is thought to be a starting point of all pathways leading to UF formation. Micro-ribonucleic acids (miRNAs) are non-coding single-stranded RNAs about 22 nucleotides in length, that regulate gene expression. One of recent advances in this field is the comprehension of the role of miRNAs in tumorigenesis. Alterations in the levels of miRNAs are related to the formation and growth of several tumors which show a distinct miRNA signature. The aim of this review is to summarize the current data about the role of miRNAs in the pathophysiology of UFs. We also discuss future directions in the miRNA research area with an emphasis on novel diagnostic opportunities or patient-tailored therapies. In our opinion data concerning the regulation of miRNA and its gene targets in the UFs are still insufficient in comparison with gynecological malignancies. The potential translational use of miRNA and derived technologies in the clinical care is at the early phase and needs far more evidence. However, it is one of the main areas of interest for the future as the use of miRNAs in the diagnostics and treatment of UFs is a new and exciting opportunity.

Expression Profile and up-Regulation of Telomere-Associated Proteins In Multiple Myeloma

Abstract 4050 The role of the telomeres in the mechanisms of ageing and carcinogenesis has generated a considerable interest as a novel approach to the treatment of many cancers. Telomeres are nucleoproteins structures that protect the ends of eukaryotic chromosomes, which are particularly vulnerable due to progressive shortening in almost all dividing cells. The telomere length was observed as a critical factor in the initiation and progression of human cancers, and it is associated to chromosomal instability. Most immortal cells possess enzymatic activity of telomerase. This suggests that telomerase activity and telomere length maintenance may be required for unlimited cell proliferation, tumorigenesis, and protection, allowing the evasion of apoptosis in cancer development. The telomerase activity could also be regulated positively or negatively by post-trancriptional and/or post-translational modification of the enzyme without transcriptional up-regulation of human telomerase reverse transcriptase (hTERT) mRNA. In this work, we analyze the expression data of all genes involved in telomerase activity. Patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), multiple myeloma (MM) and plasma cell leukemia (PLC) were studied through gene expression profiling analysis (Human Genome U133 Plus 2.0 arrays, Affymetrix). We identify 21 deregulated genes, implicated directly in telomere length maintenance activity in clonal plasma cells compared with normal cells (20 up-regulated and 1 down-regulated). These genes are MYC, KRAS, HSPA9, RB1 and members of the families: Small nucleolar ribonucleoproteins (H/ACA snoRNPs), A/B subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs), and 14-3 -3 family. In conclusion, the myeloma cells acquire the telomere maintenance capability without deregulation of the human telomerase RNA gene (hTERC) and hTERT gene expression. It is an alternative lengthening of telomeres mechanism that has effect in the regulation of the BAD activity in apoptosis. The mechanism is based on preventing the partially-denatured proteins from aggregating, telomere maintenance through the correct processing and intranuclear trafficking of hTERC, telomerase reactivation and telomere stabilization, and efficient accumulation of hTERT in the nucleus. Thus, the findings of this study may help to improve telomerase-based therapy for multiple myeloma. Disclosures: No relevant conflicts of interest to declare.