Concerning band q13: (i) 50 tumors (approximately 17%) were co-amplified for BCL-1, HST & INT-2; (ii) in 3 cases, amplification extended to the SEA gene; (iii) in 6 carcinomas, BCL-1 was the only amplified marker.
Overexpression of cyclin D1 is observed in mammary carcinomas as a result of gene amplification and in parathyroid adenomas and centrocytic B-cell lymphomas as a consequence of chromosomal rearrangements and juxtaposition of the cyclin D1 gene to strong transcriptional control elements.
These findings suggest that the PRAD-1/cyclin D1 gene may be an important target of 11q13 amplifications in laryngeal carcinomas and the activation of this gene may be involved in the progression of these tumors.
Cyclin D1 gene amplification in esophageal carcinomas can be evaluated by differential polymerase chain reaction and may provide useful prognostic information.
Cyclin D1, an oncogene that has a critical role in G1 progression of the cell cycle, has been observed to be amplified in carcinomas of the breast and head and neck, and translocated in parathyroid adenomas and centrocytic lymphomas.
Cyclin D1 (PRAD1) protein expression in breast cancer: approximately one-third of infiltrating mammary carcinomas show overexpression of the cyclin D1 oncogene.
Although only three patients with parathyroid carcinoma were studied, two of the patients' tumors stained for cyclin D1, raising the possibility that the frequency of cyclin D1 overexpression may be even greater in carcinomas.
The cyclin D1, referred to as PRAD-1, has been mapped to the 11q13 region, and its expression has been detected in squamous cell lines and several primary esophageal carcinomas.
Their association with cyclin D1 deregulation in advanced carcinomas could indicate a possible cooperative effect in the progression of these neoplasms.
Moreover, eight benign lesions, two borderline tumours and 11 carcinomas proved to be suitable for the analysis of cyclin D1 transcript, and emerging data demonstrated significant agreement between protein abundance and mRNA expression.
By means of immunohistochemistry, we retrospectively investigated the overexpression of cyclin D1 and p53 genes in a series of 28 parotid gland carcinomas.
Expression of the Bcl-2 family of apoptosis-related genes (bcl-2, bcl-X, mcl-1, and bax) and the proliferation- and apoptosis-related genes p53 and cyclin D-1 were determined in 40 low-T-stage laryngeal carcinomas and in uvular epithelium from patients without SCC.
Early immunohistochemical prognostic studies produced equivocal results but we, and others, have recently shown that strong staining for cyclin D1 is more likely to be seen in well differentiated, estrogen receptor positive carcinomas.
In order to characterize homogeneously staining regions (HSR) and other 11q13 rearrangements identified cytogenetically, we performed fluorescence in situ hybridization (FISH) using a CCND1 cosmid and five YAC clones spanning chromosomal bands 11q13-14 on metaphase cells from 14 primary and one metastatic head and neck carcinomas.