introduction: the tumor suppressor p53 protein can induce apoptosis in some cellular contexts. among the apoptosis-inducing genes, p53 has received the most attention for cancer gene therapy. in this study, the role of dendrosome and lipofectin mediated normal cdna of tp53 into molt-4, ccrf-cem(t-iymphoma) and k562 cell lines was assessed. material and methods: at first, ccrf-cem, mol t-4 and k...

During endomitosis, megakaryocytes undergo several rounds of DNA synthesis without division leading to polyploidization. In primary megakaryocytes and in the megakaryocytic cell line CHRF, loss or knock-down of p53 enhances cell cycling and inhibits apoptosis, leading to increased polyploidization. To support the hypothesis that p53 suppresses megakaryocytic polyploidization, we show that stabl...

Master regulator protein p53, popularly known as the "guardian of genome" is the hub for regulation of diverse cellular pathways. Depending on the cell type and severity of DNA damage, p53 protein mediates cell cycle arrest or apoptosis, besides activating DNA repair, which is apparently achieved by regulation of its target genes, as well as direct interaction with other proteins. p53 is known ...

Abstract Background: Adult T-cell leukemia/lymphoma (ATLL) is caused by human T-cell lymphotropic virus type-1 (HTLV-1).  HTLV-1 oncogenes can induce malignancy through controlled gene expression of cell cycle checkpoints in the host cell. HTLV-I genes play a pivotal role in overriding cell cycle checkpoints and deregulate cellular division. In this study, we aimed to determine and comp...

Although the prognostic value of p53 abnormalities in Stage III microsatellite stable (MSS) colorectal cancers (CRCs) is known, the gene expression profiles specific to the p53 status in the MSS background are not known. Therefore, the current investigation has focused on identification and validation of the gene expression profiles associated with p53 mutant phenotypes in MSS Stage III CRCs. G...

Aberrant expression of ras genes has been recognized in several human cancers and is associated with the development of the disease. Thus, revealing the mechanisms that regulate the expression of ras genes is critical for understanding their role in the process of tumorigenesis. Transcriptional regulation of the H-ras gene, involves nuclear factors recognizing elements in the promoter region of...

p51/p63 is a novel p53 homologue that has been shown to act as a transcriptional activator through the p53-binding sequence of the p21/WAF1 promoter and to induce apoptosis when it is expressed transiently in a human tumor cell line. We developed transcription assay systems for these two related genes in both Saccharomyces cerevisiae and mammalian cells and used them to investigate the function...

Caspases, a family of cysteine proteases, cleave substrates and play significant roles in apoptosis, autophagy, and development. Recently, our group identified 72 genes that interact with Death Caspase-1 (DCP-1) proteins in Drosophila by genetic screening of 15,000 EP lines. However, the cellular functions and molecular mechanisms of the screened genes, such as their involvement in apoptosis an...

We aimed to evaluate the interaction of two tumor suppressor genes PTEN and p53 and their relationship with cell cycle protein proliferating cell nuclear antigen (PCNA) in hepatocellular carcinoma (HCC). A total of 124 resected HCC paraffin specimens were collected from 1987 to 1999 for immunohistochemistry. Expression of PTEN, p53 and PCNA in HCC were analyzed for clinicopathologic correlation...