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Z Danilovic

Publications and source records attributed to Z Danilovic.

5 recordsLinked to original sources
PubMedDate not supplied

Overexpression of p53 protein is common in premalignant head and neck lesions.

In order to determine whether or not the p53 gene is involved in the malignant transformation of the head and neck carcinoma HNSCC, we have analyzed archival specimens from 527 primary head and neck lesions and 27 corresponding lymph node metastases. Nuclear p53 protein was present in 107 of 190 (56%) dysplasias, 61 of 102 (60%) carcinoma in situ (CIS), and 262 of 493 (53%) carcinomas. The p53 score did not increase significantly with progression of these lesions from dysplasia to CIS and to carcinoma. All 357 normal samples of head and neck tissues were negative. The majority of the 172 sets of premalignant and malignant lesions displayed concordant p53 staining patterns. The staining was incongruous in only six cases. The p53 staining results were congruent in all 27 pairs of primary and metastatic (lymph nodes) tumors. These data strongly suggest that p53 protein could be altered in a very early phase of the head and neck tumorigenesis and is maintained during tumor progression and metastatic spread. Mutations in p53 were examined in 11 cases that exhibited high levels of p53 protein as detected by immunohistochemistry using PAb 1801 MAb. Mutation analysis was performed by direct sequencing of the PCR amplification products of exons 5 through 8, which contain greater than 90% of p53 mutations found in tumors. Three of 11 HNSCC had mutations at codon 130 (C to A), 193 (A to T), 283 (G to C), respectively. No mutations were found in the other 8 samples within the regions examined. However, they may have mutations in unsequenced regions of p53 or may have wild type protein that accumulates for other reasons.

Adult↗
PubMedDate not supplied

Immunohistochemical detection of TGF-alpha, EGF-R, c-erbB-2, c-H-ras, c-myc, estrogen and progesterone in benign and malignant human breast lesions: a concomitant expression.

The expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor receptor (EGF-R) and oncogenes c-erbB-2, c-H-ras, c-myc, as well as estrogen (ER) and progesterone (PR) receptors were studied immunohistochemically in the tissue of 21 benign and 58 malignant human breast lesions. Twenty nine (50%) of 58 carcinomas were positive for EGF-R and c-erbB-2 product, 55 (94.8%) for c-myc product, 9 (15.5%) for c-H-ras product and 17 (29%) for TGF-alpha. Eighteen of 58 (31%) carcinomas were estrogen receptor positive and 22 (38%) were positive for progesterone receptor. No correlation was found between expression of each investigated parameter and the clinical stage or degree of histological differentiation of the carcinomas. However, a significant positive correlation was observed between lymph node involvement and c-erbB-2 and EGF-R/c-erbB-2 positive tumors. A strong correlation was also observed between high levels of EGF-R and low levels of estrogen receptor. In 15 of 17 cases we found simultaneous expression of EGF-R and TGF-alpha. We also found interesting patterns in concomitant expression of the investigated parameters suggesting a possible cascade of events that occur in breast cancer cells.

Breast Diseases↗