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The increasing use of silica nanoparticles (SiNPs) in various applications including industrial, agriculture, and medicine has raised concerns about their potential risks to human health. Various nanotoxicity researches have been done on the assessment of SiNPs' toxic effects; however, a few in vivo investigations exist. In this investigation, an in vivo study was done in order to evaluate the oral toxicity of SiNPs. The biochemical levels of 19 different serum parameters were assessed. Moreover, the histopathological changes have been examined as well. We showed that SiNPs with diameters of 10-15 nm in size can cause significant changes in albumin, cholesterol, triglyceride, total protein, urea, HDL, and LDL as well as in alkaline phosphatase and aspartate aminotransferase activity. In addition, histopathological examinations demonstrated that SiNPs have toxic effects on various tissues including liver, kidney, lung, and testis.

Recent evidence suggests that mesenchymal stem cells (MSCs) have promising therapeutic potential for a broad range of diseases. Because the percentage of MSCs obtained from tissues is very low for cell therapy applications, ex vivo expansion of MSCs is necessary, but aging, loss of stemness and undesired differentiation of them during in vitro cultivation reduces their effectiveness. For achieving ideal therapeutic potential of MSCs in tissue regenerative purposes, it is necessary to retain their stemness properties in vitro. This review emphasis on the last updates in preserving the self-renewal capability of stem cells through in vitro expansion with different parameters.

Over-expression of the proto-oncogene survivin in colorectal cancer stem cells (CCSCs) is thought to be one the primary causes for therapy failure. It has also been reported that tumor suppressor miR-16-1 is down-regulated in colorectal cancer (CRC) cells. Therefore, the search for new anti-proliferative agents which target survivin or miR-16-1 in CCSCs is warranted. Several studies have shown that prodigiosin isolated from cell wall of Serratia marcescens induces apoptosis in different kinds of cancer cells. Here, we investigated the effects of prodigiosin on HCT-116 cells that serve as a model for CRC initiating cells with stem-like cells properties. HCT-116 cells were treated with 100, 200 and 400 nM prodigiosin after which cell number, viability, growth-rate, survivin and miRNA-16-1 expression, caspase-3 activation and apoptotic rate were evaluated. Prodigiosin decreased significantly growth-rate in a dose-and time-dependent manner. After a 48 h treatment with 100, 200 and 400 nM prodigiosin, growth-rates were measured to be 84.4 ± 9.2 %, 58 ± 6.5 % and 46.3 ± 5.2 %, respectively, compared to untreated cells. We also found that treatment for 48 h with indicated concentrations of prodigiosin resulted in 41 %, 54.5 % and 63 % decrease in survivin mRNA levels and induced 32 %, 48 % and 61 % decrease in survivin protein levels as well as resulted in 128.3 ± 10 %, 178.7 ± 6.1 % and 205 ± 7.6 % increase in caspase-3 activation respectively compared to untreated cells. Prodigiosin caused a significant increase in miRNA-16-1 expression at a concentration of 100 nM and treatment with different concentrations of prodigiosin resulted in 2.2- to 3-fold increase in miRNA-16-1/survivin ratios compared to untreated cells. An increase in number of apoptotic cells ranging from 28.2 % to 86.8 % was also observed with increasing prodigiosin concentrations. Our results provide the first evidence that survivin and miRNA-16-1 as potential biomarkers could be targeted in CRC initiating cells with stem-like cells properties by prodigiosin and this compound with high pro-apoptotic capacity represents the possibility of its therapeutic application directed against CCSCs.

Background: Abnormal activation of the Wnt/β-catenin signaling pathway increases survivin expression that is involved in hepatocarcinogenesis. Therefore, downregulation of survivin may provide an attractive strategy for treatment of hepatocellular carcinoma. In this regard, little is known about the anticancer effects of prodigiosin isolated from cell wall of Serratia marcescens on the survivin expression and induction of apoptosis in hepatocellular carcinoma cells. Methods: Human hepatocellular carcinoma (HepG2) cells were treated with 100-, 200-, 400-, and 600-nM prodigiosin after which morphology of cells, cell number, growth inhibition, survivin expression, caspase-3 activation, and apoptotic rate were evaluated by inverted microscope, hemocytometer, MTT assay, RT-PCR, fluorometric immunosorbent enzyme assay, and flow cytometric analysis, respectively. Results: Prodigiosin changed morphology of cells to apoptotic forms and disrupted cell connections. This compound significantly increased growth inhibition rate and decreased metabolic activity of HepG2 cells in a dose- and time-dependent manner. After 24-, 48-, and 72-h treatments with prodigiosin at concentrations ranging from 100 nM to 600 nM, growth inhibition rates were measured to be 1.5–10%, 24–47.5%, and 55.5–72.5%, respectively, compared to untreated cells. At the same conditions, metabolic activities were measured to be 91–83%, 74–53%, and 47–31% for indicated concentrations of prodigiosin, respectively, compared to untreated cells. We also found that treatment of HepG2 cells for 48 h decreased significantly cell number and survivin expression and increased caspase-3 activation in a dose-dependent manner. Specifically, treatment with 600-nM prodigiosin resulted in 77% decrease in cell number, 88.5% decrease in survivin messenger RNA level, and 330% increase in caspase-3 activation level compared to untreated cells. An increase in the number of apoptotic cells (late apoptosis) ranging from 36.9% to 97.4% was observed with increasing prodigiosin concentrations. Conclusion: From our data, prodigiosin is an attractive compound that turns the profile of high-level survivin expression in hepatocellular carcinoma cells into that of normal cells and may provide a novel approach to the hepatocellular carcinoma-targeted therapy.

In acute lymphoblastic leukemia (ALL), resistance to chemotherapy is associated with inactivation of p53 and upregulation of survivin. Thus, targeting the p53 and survivin expression may provide an attractive strategy for ALL treatment. It has been shown that fish-oil-derived docosahexaenoic acid (DHA) activates several antitumorigenic mechanisms in tumor cells, but little is known regarding the role of DHA on modulating p53 and survivin expression in ALL cells. In this study, we investigated the alterations of the p53 and survivin expression and induction of apoptosis in DHA-treated Molt-4 cells that serve as a model for ALL cells. Molt-4 cells were treated with 50, 100, 150, and 200 μM DHA after which cell proliferation, survivin mRNA and protein levels, p53 protein level, caspase-3 activation, and apoptotic rates were evaluated by different cellular and molecular techniques. After 48- and 72-h treatments with DHA at concentrations ranging from 50 to 200 μM, cell proliferation rates were measured to be 80.5-44.4%, and 73.4-14.4%, respectively, compared to untreated cells. We also found that treatment for 48 h with 200 μM DHA resulted in 10.8- and 3.6-fold increase in p53 protein level and caspase-3 activation followed by 4.7-and 1.6-fold decrease in survivin mRNA and protein levels, respectively, compared to untreated cells. Treatment of cells with different concentrations of DHA dramatically increased the p53/survivin and caspase-3/survivin ratios by 2.8- to 16.9-fold and 3.3 to 5.6-fold increases, respectively, compared to untreated cells. A decrease in the number of cells ranging from 16% to 70% and an increase in the number of apoptotic cells ranging from 9.3% to 93% was also observed with increasing DHA concentrations. In conclusion, p53 and survivin may provide promising targets of DHA in ALL cells and this compound with high proapoptotic capacity represents the possibility of its therapeutic application for ALL treatment.

Rhabdomyosarcoma (RMS) is the most common pediatric soft-tissue malignant tumor. Treatment of RMS usually includes primary tumor resection along with systemic chemotherapy. Two-dimensional (2D) cell culture systems and animal models have been extensively used for investigating the potential efficacy of new RMS treatments. However, RMS cells behave differently in 2D culture than in vivo, which has recently inspired the adoption of three-dimensional (3D) culture environments. In the current paper, we will describe the detailed methodology we have developed for fabricating a 3D engineered model to study alveolar RMS (ARMS) in vitro. This model consists of a thermally cross-linked collagen disk laden with RMS cells that mimics the structural and bio-chemical aspects of the tumor extracellular matrix (ECM). This process is highly reproducible and produces a 3D engineered model that can be used to analyze the cytotoxicity and autophagy induction of drugs on ARMS cells. The most improtant bullet points are as following: We fabricated 3D model of ARMS. The current ARMS 3D model can be used for screening of chemotherapy drugs. We developed methods to detect apoptosis and autophagy in ARMS 3D model to detect the mechansims of chemotherapy agents.

In recent decades, mesenchymal stem cells originated from adipose tissue (adipose-derived stem cells, ASCs) have gained increased attention for production of cell-based therapeutics. Emu oil as a natural compound showed antioxidant effects in previous studies. The goal of this study was to investigate the effect of crude emu oil on the proliferation, cell cycle progression, stemness genes expression, and in vitro wound healing potential of ASCs. An emulsion of emu oil was prepared using egg lecithin and butylated hydroxytoluene to improve bioavailability and solubility of emu oil in the expansion medium. The ASCs were treated using a series of emu oil concentrations in emulsion form, diluted in expansion medium (0.03-3 mg/ml). The emu oil-free emulsion was used as control treatment. The results revealed that emu oil (1.25 mg/ml) in emulsion form significantly (p < 0.001) increased ASCs proliferation and colony formation. Additionally, emu oil caused upregulation of stemness marker genes (Sox2, Oct4, Nanog, and Nestin) (p < 0.05). The cell cycle analysis after emu oil treatments showed an increase in the population of ASCs in S-phase of the cell cycle. Besides, an accelerated in vitro scratch wound healing was observed in emu oil-treated ASCs. Emu oil enhanced proliferation, colony formation, stemness genes expression, and in vitro wound healing of ASCs. These findings suggest that emu oil treatment could maintain the stemness of ex vivo cultivated ASCs and enhance their regenerative potential.