By NIH3T3 transfection assay in conjunction with in vitro transient neomycin selection, activated c-H-ras-1 oncogenes were detected in two squamous cell carcinoma cell lines, ZA and HOC-313, newly established from human oral cancer patients.
This investigation of oral squamous carcinoma in five individuals revealed that four of the patients were constitutionally heterozygous at the c-Ha-ras-1 locus and that the tumour from one patient had lost that heterozygosity.
Transforming growth factor alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) have been shown to be present in most squamous cell carcinomas.
One factor, hepatocyte-stimulating factor III (HSF-III), constitutively produced by human squamous carcinoma (COLO-16) cells, stimulates the synthesis of the same set of acute phase plasma proteins as the structurally distinct IL-6.
Our results support the possible involvement of gene amplification and overexpression of the EGF receptor in a subclass of squamous cell carcinomas of the head and neck.
Although no transcripts from the antisense gene were detected, the results indicate that transfection with the antisense vector provides a technique by which to modulate the number of EGF receptors on the cell surface of squamous cell carcinomas.
In this report the regulation of extracellular-associated plasminogen activator (PA) production by EGF in human squamous cell carcinomas and its influence on tumor cell-mediated degradation of extracellular matrix (ECM) is described.
Association of interferon-gamma induced growth inhibition and modulation of epidermal growth factor receptor gene expression in squamous cell carcinoma cell lines.
In this report the regulation of extracellular-associated plasminogen activator (PA) production by EGF in human squamous cell carcinomas and its influence on tumor cell-mediated degradation of extracellular matrix (ECM) is described.
Transforming growth factor alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) have been shown to be present in most squamous cell carcinomas.
One factor, hepatocyte-stimulating factor III (HSF-III), constitutively produced by human squamous carcinoma (COLO-16) cells, stimulates the synthesis of the same set of acute phase plasma proteins as the structurally distinct IL-6.
Human squamous carcinoma (COLO-16) cells synthesize and secrete hepatocyte-stimulating factor-III (HSF-III), a glycoprotein with Mr = 39,000, which stimulates the synthesis of several acute phase plasma proteins in human hepatoma (HepG2) cells.
The identification of aberrant p53 gene alleles in one-third of the tumors we tested suggests that mutations at this locus are common genetic events in the pathogenesis of squamous cell carcinomas of the esophagus.
Increased expression of the epidermal growth factor receptor has been noted in many types of tumors and is associated with gene amplification in several including epidermoid carcinoma, lung carcinoma, breast carcinoma and glioblastoma.
We have recently reported the frequency amplification of the bcl-1 locus in squamous cell carcinomas of head and neck origin, and increased copy number also has been found in some breast adenocarcinomas.
PTHrP has been consistently demonstrated by immunohistochemistry in squamous cell carcinomas and in keratinocytes present in normal skin, but not in normal or hyperplastic parathyroid tissues or other tumors.