We examined the extent of EGF consumption by EGFR in A431 cells. When 125I-EGF was added to A431 cell cultures at low or high density, at concentrations which corresponded to 10-fold excess of ligand over receptor on the cell surface, most of the 125I-EGF was consumed within 2 h. The amounts of 125I-EGF consumed were much greater than available EGFR on the A431 cells, by a factor of 6.5 in low-...

introduction: trastuzumab is a monoclonal antibody that is used in treating breast cancer. we labeled this monoclonal antibody with technetium-99m and performed in vitro and in vivo quality control tests as a first step in the production of a new radiopharmaceutical. methods: trastuzumab was labeled with technetium-99m using succinimidyl hydrazinonicotinamide (hynic) as chelator. radiochemical ...

Exposure of mammalian cells to ultraviolet (UV) light elicits a cellular response and can also lead to apoptotic cell death. In this report, we show that a 36-kDa myelin basic protein (MBP) kinase detected by an in-gel kinase assay can be dramatically activated during the early stages of UV irradiation-triggered apoptosis of A431 cells. Immunoblot analysis revealed that this 36-kDa MBP kinase c...

UNLABELLED BACKGROUND This study evaluates the potential utility of a modular nanotransporter (MNT) for enhancing the nuclear delivery and cytotoxicity of the Auger electron emitter 125I in cancer cells that overexpress the epidermal growth factor receptor (EGFR). METHODS MNTs are recombinant multifunctional polypeptides that we have developed for achieving selective delivery of short-rang...

Metastasis is a multi-step process which requires the conversion of polarized epithelial cells to mesenchymal cells, Epithelial-Mesenchymal Transition (EMT). EMT is essential during embryonic morphogenesis and has been implicated in the progression of primary tumors towards metastasis. Hypoxia is known to induce EMT; however the molecular mechanism is still poorly understood. Using the A431 epi...

A number of epidermal growth factor (EGF)-resistant clones have been isolated from human epidermoid carcinoma A431 cells (I. King and A. C. Sartorelli, Biochem. Biophys. Res. Commun., 140: 837, 1986). These cells had a higher capacity to enter a pathway of terminal differentiation, as determined by their ability to form cornified envelopes. Thus, after 6 days in culture, 10% of parental A431 ce...

Recently, we demonstrated that S100C/A11 comprises an essential pathway for growth suppression by TGFbeta in normal human keratinocytes. Nuclear transfer of S100C/A11 was a hallmark of the activation of the process. In the present study, we examined the possible deterioration in the pathway in human squamous cancer cell lines, focusing on intracellular localization of S100C/A11 and its function...

In this paper, a set of 3-methylquniazolinone derivatives were designed, synthesised, and studied the preliminary structure-activity relationship for antiproliferative activities. All target compounds performed significantly inhibitory effects against wild type epidermal growth factor receptor tyrosine kinase (EGFRwt-TK) tumour cells (A431, A549, MCF-7, NCI-H1975). particular, compound 4d 3-flu...

background:epidermal growth factor receptor (egfr) overexpression is a characteristic of several malignancies and could be considered as an excellent target for designing specific inhibitors such as anti-egfr monoclonal antibodies for cancer therapy. drawbacks exerted by large sizes of full-length antibodies have lead to the development of single chain antibodies, which benefit from having smal...