Iridium(III)-Cp*-(imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol analogues as hypoxia active, GSH-resistant cancer cytoselective and mitochondria-targeting cancer stem cell therapeutic agents.

Herein, we have introduced a series of iridium(III)-Cp*-(imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol complexes via a convenient synthetic methodology, which act as hypoxia active and glutathione-resistant anticancer metallotherapeutics. The [IrIII(Cp*)(L5)(Cl)](PF6) (IrL5) complex exhibited the best cytoselectivity, GSH resistance and hypoxia effectivity in HeLa and Caco-2 cells among the synthesized complexes. IrL5 also exhibited highly cytotoxic effects on the HCT-116 CSC cell line. This complex was localized in the mitochondria and subsequent mitochondrial dysfunction was observed via MMP alteration and ROS generation on colorectal cancer stem cells. Cell cycle analysis also established the potential of this complex in mediating G2/M phase cell cycle arrest.

CD34 cells in somatic, regenerative and cancer stem cells: Developmental biology, cell therapy, and omics big data perspective.

The transmembrane phosphoglycoprotein protein CD34 has conventionally been regarded as a marker for hematopoietic progenitors. Its expression on these cells has been leveraged for cell therapy applications in various hematological disorders. More recently, the expression of CD34 has also been reported on cells of nonhematopoietic origin. The list includes somatic cells such as endothelial cells, fibrocytes and interstitial cells and regenerative stem cells such as corneal keratocytes, muscle satellite cells, and muscle-derived stem cells. Furthermore, its expression on some cancer stem cells (CSCs) has also been reported. Till date, the functional roles of this molecule have been implicated in a multitude of cellular processes including cell adhesion, signal transduction, and maintenance of progenitor phenotype. However, the complete understanding about this molecule including its developmental origins, its embryonic connection, and associated functions is far from complete. Here, we review our present understanding of the structure and putative functions of the CD34 molecule based upon our literature survey. We also probed various biological databases to retrieve data related to the expression and associated molecular functions of CD34. Such information, upon synthesis, is hence likely to provide the suitability of such cells for cell therapy. Moreover, we have also covered the existing cell therapy and speculated cell therapy applications of CD34+ cells isolated from various lineages. We have also attempted here to speculate the role(s) of CD34 on CSCs. Finally, we discuss number of large-scale proteomics and transcriptomics studies that have been performed using CD34+ cells.

Human embryonic stem cell differentiation into insulin secreting ß-cells for diabetes.

hESC (human embryonic stem cells), when differentiated into pancreatic ß ILC (islet-like clusters), have enormous potential for the cell transplantation therapy for Type 1 diabetes. We have developed a five-step protocol in which the EBs (embryoid bodies) were first differentiated into definitive endoderm and subsequently into pancreatic lineage followed by formation of functional endocrine ß islets, which were finally matured efficiently under 3D conditions. The conventional cytokines activin A and RA (retinoic acid) were used initially to obtain definitive endoderm. In the last step, ILC were further matured under 3D conditions using amino acid rich media (CMRL media) supplemented with anti-hyperglycaemic hormone-Glp1 (glucagon-like peptide 1) analogue Liraglutide with prolonged t(½) and Exendin 4. The differentiated islet-like 3D clusters expressed bonafide mature and functional ß-cell markers-PDX1 (pancreatic and duodenal homoeobox-1), C-peptide, insulin and MafA. Insulin synthesis de novo was confirmed by C-peptide ELISA of culture supernatant in response to varying concentrations of glucose as well as agonist and antagonist of functional 3D ß islet cells in vitro. Our results indicate the presence of almost 65% of insulin producing cells in 3D clusters. The cells were also found to ameliorate hyperglycaemia in STZ (streptozotocin) induced diabetic NOD/SCID (non-obese diabetic/severe combined immunodeficiency) mouse up to 96 days of transplantation. This protocol provides a basis for 3D in vitro generation of long-term in vivo functionally viable islets from hESC.

Cultured melanocytes: from skin biopsy to transplantation.

Restoration of cutaneous pigmentation has been achieved in stable vitiligo by autologous melanocyte transplantation. This study was aimed to develop a methodology to deliver melanocytes to vitiliginous area following their processing and culture in a centralized facility. Here we report a methodology to culture melanocytes on carrier films, transport the cells, and graft them on vitiliginous areas. The salient features of this study include: 1) development of polylactic acid (PLA) films that support melanocyte attachment, growth, and delivery; 2) establish transport conditions for skin biopsies from hospitals; 3) establish transport conditions for cultured cells from cell processing center to hospitals. Results suggest that PLA films could serve as carriers for melanocytes during transport. "Upside-down" application of the graft results in the migration of cells from the films into the dermabraded area. The transport conditions ensure cell viability for 96 h. This system could help clinicians, who do not have access to cell culture facilities, transplant cultured melanocytes in a cost-effective manner.

8-Methyl-4-(3-diethylaminopropylamino) pyrimido [4',5';4,5] thieno (2,3-b) quinoline (MDPTQ), a quinoline derivate that causes ROS-mediated apoptosis in leukemia cell lines.

The present study reports the biological activity of 8-methyl-4-(3-diethylamino-propylamino) pyrimido [4';5';4,5] thieno (2,3-b) quinoline (MDPTQ), a quinoline derivative structurally related to ellipticine and suggests a possible mechanism through which the compound induces apoptosis in carcinoma cell lines. Out of the 8 cell lines used in the study as representatives of different types of cancer, MDPTQ was found to be effective only against leukemia cell lines (HL-60 and K-562) whereas it had no effect on normal human bone marrow cells (BMC) which were used as controls. Fall mitochondrial membrane potential and increased reactive oxygen species (ROS) were mainly responsible for inducing apoptosis in the two cell lines. Cell death was demonstrated by increase in caspase 3 activity as well as phosphatidyl serine exposure. Pre-incubation with N-acetylcysteine (NAC) reduced the increased ROS and caspase 3 activity as well as phosphatidyl serine exposure. MDPTQ also caused cell cycle arrest in these cell lines. The above study for the first time reports the mode of action of a quinoline derivative, which could be a possible future candidate for leukemia therapy. However, there are lot of questions that need to be answered in terms of signalling pathways and its effects on animal models.