Production of Large Numbers of Size-controlled Tumor Spheroids Using Microwell Plates

Tumor spheroids are increasingly recognized as an important in vitro model for the behavior of tumor cells in three dimensions. More physiologically relevant than conventional adherent-sheet cultures, they more accurately recapitulate the complexity and interactions present in real tumors. In order to harness this model to better assess tumor biology, or the efficacy of novel therapeutic agents, it is necessary to be able to generate spheroids reproducibly, in a controlled manner and in significant numbers.The AggreWell system consists of a high-density array of pyramid-shaped microwells, into which a suspension of single cells is centrifuged. The numbers of cells clustering at the bottom of each microwell, and the number and ratio of distinct cell types involved depend only on the properties of the suspension introduced by the experimenter. Thus, we are able to generate tumor spheroids of arbitrary size and composition without needing to modify the underlying platform technology. The hundreds of microwells per square centimeter of culture surface area in turn ensure that extremely high production levels may be attained via a straightforward, nonlabor-intensive process. We therefore expect that this protocol will be broadly useful to researchers in the tumor spheroid field.     

The effects of FTO gene rs9939609 polymorphism on the association between breast cancer and dietary intake

Breast cancer (BC) is the leading cause of cancer‐related deaths in females worldwide and is related to genetic and environmental factors. Dietary components may strongly influence the risk of BC. A possible association was also reported between the fat mass and obesity‐associated (FTO) single‐nucleotide polymorphisms (SNPs) and BC. This study aimed to investigate the impact of FTO rs9939609 polymorphism on the association between BC and dietary intake. This study was conducted on 180 women with BC as the case group and 360 healthy women as the control group. The dietary intakes were assessed by a valid 168‐item food frequency questionnaire (FFQ). The FTO gene was genotyped for rs9939609 polymorphism. After adjusting the confounding variables, there was no significant association between dietary intake and BC in individuals without risk allele. A positive association between dietary intake of omega‐6 fatty acids and BC was found only in individuals with risk allele of FTO gene (OR: 1.31, 95% CI: 1.08–1.60, p: 0.006). FTO gene risk allele may influence the effect of diet on breast cancer risk. Further studies are needed to assess the possible effects of the FTO genotype on the association between BC risk and dietary components.     

Chitooligosaccharide-mediated neuroprotection is associated with modulation of Hsps expression and reduction of MAPK phosphorylation

There is mounting evidence implicating the role of oxidative stress induced by reactive oxygen species (ROS) in neurodegenerative disease, including Alzheimer's disease. In this study we aimed to investigate the possible protective effect of chitooligosaccharide (COS), an antioxidant oligosaccharide, on hydrogen peroxide induced apoptosis in NGF-differentitated rat pheochromocytoma (PC12) cells. COS treatment reversed the decrease of cell viability induced by H(2)O(2) and this was associated with diminished intracellular ROS and decreased level of cytosolic Ca(2+). Additionally, COS contributed to up-regulation of Bcl-2, down regulation of Bax protein and reduction of cleaved Caspase-3 protein. COS treatment stabilized Nrf2 in nucleus and increased the Hsp70 level within cell while down-regulated Hsp90 expression. Moreover, COS could inhibit the phosphorylation of different mitogen activated protein kinases (MAPKs), whose aberrant phosphorylation has been implicated in AD. Our findings suggest that heat shock response and MAPK cascades are both involved in cell survival, and by concomitantly regulating both pathways, COS can be a promising agent in treating neurodegenerative diseases.