We have previously shown by examining the anchorage dependence, density-dependent inhibition of growth, LETS protein and microfilament bundles that the transformed phenotype of the parental tumours are suppressed in hybrids between rat embryo fibroblast (REF) and mouse tumour cells (TA3B). Hybrids between TA3B and Syrian hamster sarcoma cells (BHK-B1) also show suppression. We now demonstrate t...

Tumorigenicity and radiosensitivity of related cell lines expressing distinct p53 mutants were analyzed in parallel with key components of the antioxidant metabolic pathway. Six sublines deriving from the same parental cell population and expressing either the mutant p53K130R or p53V270F were investigated. Both mutations abrogate the transcriptional activity of p53 as well as its ability to ind...

The purpose of tumorigenicity testing, as applied not only to cell substrates used for viral vaccine manufacture but also stem cells used for cell-based therapy, is to discriminate between cells that have the capacity to form tumors and cells that do not. Therefore, tumorigenicity testing is essential in assessing the safety of these biological materials. Recently developed NOD/Shi-scid IL2Rg(n...

The biological functions of the BC047440 gene highly expressed by hepatocellular carcinoma (HCC) are unknown. The objective of this study was to reconstruct antisense eukaryotic expression vectors of the gene for inhibiting HepG(2) cell proliferation and suppressing their xenograft tumorigenicity. The full-length BC047440 cDNA was cloned from human primary HCC by RT-PCR. BC047440 gene fragments...

Twist1 is a master regulator of epithelial mesenchymal transition and carcinoma metastasis. Twist1 has also been associated with increased malignancy of human glioma. However, the impact of inhibiting Twist1 on tumorigenicity has not been characterized in glioma models in the context of different oncogenic transformation paradigms. Here we used an orthotopic mouse glioma model of transplanted t...

The transformed clonal isolates of Indian muntjac diploid cells by a mouse sarcoma virus, 43-2XV, were tested for tumorigenicity in athymic nude mice. In spite of the indistinguishable transformed morphology, the tumorigenicity exhibited four different patterns: (a) no tumor formation; (b) slowly growing regressive tumor formation; (c) rapidly growing regressive tumor formation; and (d) rapidly...

The present study aimed to investigate whether the inhibition of cluster of differentiation (CD)44 expression reduces the tumorigenicity of CD44+ cancer stem cells in hypopharyngeal cancer. To assess this, effective recombinant CD44 short hairpin RNA-expressing lentiviruses were produced. Lentivirus-mediated RNA interference (RNAi) was then used to knockdown CD44 gene expression in the hypophar...

Human Pluripotent Stem Cell (PSC)-derived cell therapy holds enormous promise because of the cells' "unlimited" proliferative capacity and the potential to differentiate into any type of cell. However, these features of PSC-derived cell products are associated with concerns regarding the generation of iatrogenic teratomas or tumors from residual immature or non-terminally differentiated cells i...

The relation of in vitro properties to tumorigenicity was studied using eight sublines of the human breast cancer cell line MCF-7. Four of the eight were tumorigenic in estrogen-treated nude mice. The sublines differed for each of the in vitro properties measured, and no property correlated perfectly with tumorigenicity. Cytochalasin B-induced multinucleation was a property of all four tumorige...