p53 is a key tumor suppressor gene that is targeted for inactivation during human tumorigenesis. In this study, we produced and characterized polyclonal antihuman p53 antibody. The cDNA encoding the completehuman p53 protein was cloned into pGEX-4T-1 and expressed in Escherichia coli as a fusion protein with Schistosoma japonicum glutathione S-transferase (GST). The rabbits were immunized...

Genetic evidence has implicated both Mdm2 and MdmX as essential in negative regulation of p53. However, the exact role of MdmX in this Mdm2-dependent protein degradation is not well understood. Most, if not all, previous Mdm2 studies used GST-Mdm2 fusion proteins in the in vitro assays. Here, we show that the p53 polyubiquitination activity of GST-Mdm2 is conferred by the GST tag and non-GST-ta...

BACKGROUND It has been reported that the activity of glutathione S-transferase (GST) is over-expressed in plasma and esophagus biopsies in Iranian patients suffering from esophageal squamous cell carcinoma (SCC). The aim of this study was to find out the frequency of GST-P genotypes in these patients. Moreover, the association of GST-P genotypes with p53 protein accumulation in esophageal epith...

OBJECTIVE Colorectal cancer is one of the major contributors to cancer death worldwide. Lack of reliable colorectal cancer markers has hampered the management of these cancer patients. Our main purpose was to study the correlation between histopathological variables of colorectal adenocarcinomas and identify histopathological markers that are of prognostic value in patients with colorectal canc...

background: tumour suppressor genes such as tp53, brca1 and rad51 are involved in dna repair and their malfunctions result in genomic instability and cancer. wild type (wt) tp53 binds to brca1and rad51 in vivo and in vitro. however, mutated tp53 in tumours can interfere with wt tp53 function. we studied how mutation of tp53 in mda-mb-468 cell line could affect its binding capacity and interfere...

We studied malignant melanoma cell line Me45 and human ovarian carcinoma cell line SKOV-3 (resistant to cisplatin, adriamycin and diphtheria toxin), assessing their expression level of p53, HSP70 and glutathione S-transferase GST-π before and after chemotherapy with cisplatin. These proteins may be responsible for the occurrence of chemoresistance in cancer patients. To assess protein expressio...

Previous reports have documented an attenuated p53 response to DNA damage in hepatocytes isolated from enzyme-altered foci (EAF). Here, we have studied this p53 response in vivo in rats with EAF. These animals received repeated doses of diethylnitrosamine (DEN) for 6 weeks and a challenging dose 24 h before death. Liver sections were then analysed using an immunohistological procedure for p53, ...

We investigated the utility of examining biological markers to predict chemoresponse and survival. The subjects consisted of 39 unresectable gastric cancer patients treated with a combination of 5-fluorouracil and cis-platinum. The expression of p53, bcl-2, thymidylate synthase (TS), glutathione S-transferase pi (GST-pi), and vascular endothelial growth factor (VEGF) in the formalin-fixed biops...

Background: Extrahepatic biliary atresia (EHBA) is a chronic obstructive cholangiopathy of infancy with obscure aetiology. I recently reported unanimous strong immunohistochemical staining against neutrophil elastase in EHBA liver biopsies, with variable degrees of fibrosis, and variable CD14+ monocytes intensity staining. Neutrophil inflicted cellular damage is a crucial step for regeneration ...

PURPOSE To examine the prognostic significance of expression of glutathione s-transferase pi (GST-pi) and p53 in patients treated with radiation alone for locally advanced head and neck cancer [Radiation Therapy Oncology Group (RTOG), trial 9003] or radiation +/- concomitant chemotherapy as postoperative adjuvant therapy (RTOG trial 9501). EXPERIMENTAL DESIGN Immunohistochemical staining for ...