Laminin-5 as a marker of invasiveness in cervical lesions.

BACKGROUND: Treatment decisions for cervical cancer, a common disease worldwide, depend on demonstrating whether or not tumor invasion of the surrounding tissue has occurred. Invasion can be difficult to assess by standard histopathologic methods, especially when limited amounts of tissue are available. Several studies of a variety of cancers have reported increased expression of laminin-5-an important attachment protein for epithelial cells-in invasive carcinomas. This study was designed to investigate whether the presence of laminin-5 is related to the invasive capacity of cervical lesions. METHODS: We used immunohistochemical methods to stain archival, paraffin-embedded sections of cervical lesions with a polyclonal antibody specifically targeting the gamma2 chain of human laminin-5 protein. The study sample included 23 lesions of mild and moderate dysplasia (cervical intraepithelial neoplasia [CIN] 1 and 2, respectively), 32 lesions of severe dysplasia or carcinoma in situ (CIN 3), 15 lesions of microinvasive cancer, and 20 lesions of frankly invasive cancer. Cellular proliferative activity was also investigated by the use of monoclonal MIB-1 (directed against the antigen Ki-67) and anticyclin A antibodies. RESULTS: Invasiveness of cervical lesions was positively associated with immunohistochemical staining of the gamma2 chain of laminin-5 (two-sided P =.001). All CIN 1 and CIN 2 lesions-except one CIN 2 lesion later shown to be invasive cancer-and 21 CIN 3 lesions tested negative for the gamma2 chain of laminin-5. Eleven CIN 3 lesions and all invasive cancers tested positive for this protein. One lymph node metastasis and a pleural metastasis from one of the patients with invasive cancer showed strong immunohistochemical positivity. Proliferative activity increased with advancement of the lesion but was not confined to cells positive for the gamma2 chain of laminin-5. CONCLUSIONS: These data suggest that antibodies directed against the gamma2 chain of laminin-5 can identify cervical lesions with invasive capacity and thus may be useful as a sensitive marker of early invasion.

Identification of two distinct deleted regions on chromosome 13 in prostate cancer.

Aberrations of 13q occur frequently in prostate cancer and this chromosome contains two known tumor suppressor genes, BRCA2 and Rb1. This study analysed 13q LOH, DNA ploidy, BRCA2 mutation and pRb expression in prostate cancers. In total, 13q deletions were found in 18 of 36 tumors but did not correlate with histological grade, stage or DNA ploidy. Two smallest regions of overlapping deletions were defined: one flanked by D13S218 and D13S153; the other flanked by D13S31 and D13S137. BRCA2 was less frequently deleted whereas Rb1 did have a high frequency of deletion. None of the two genes was located in any of these two regions. Furthermore, BRCA2 mutation was not found in the five tumors where deletions had involved the BRCA2 locus. Neither did the Rb1 deletion correlate with absent pRb expression. In addition, tetraploidy was found in 14 out of 25 tumors analysed and correlated with aberrant pRb expression. Our results indicate that 13q deletion is an early non-random event. Tumor suppressor genes other than BRCA2 or Rb1 may be the target of 13q deletions. Aberrant pRb expression may not reflect the two-hit Rb1 inactivation but may be involved in the tetraploidization of prostate cancer cells.

The impact of tumour angiogenesis, p53 overexpression and proliferative activity (MIB-1) on survival in squamous cervical carcinoma.

Tumour angiogenesis (antifactor VIII-related antigen antibody), p53 overexpression (DO-1) and proliferative activity (MIB-1) were immunohistochemically analysed for the prediction of long-term survival in 113 patients with squamous cervical carcinoma. The median follow-up time was 82 months (range 72-99). In early stages (IB-IIA), neovascularisation was significantly related to tumour size. Significantly more patients in stage IIA had high tumour vascularity compared to stage IB (P < 0.01) but no significant difference was found between early and advanced stages (IIB-IVB) of cervical carcinoma. p53 overexpression was correlated to the stage of disease (P < 0.01). No relationship was found between tumour angiogenesis, p53 overexpression or MIB-1 and pelvic lymph node metastases, histological subtype or differentiation. Tumours with more than 50% p53 overexpression was significantly correlated with survival in the univariate analysis, but no independent predictive value was found. It is concluded that immunohistochemically detectable p53 overexpression as measured by DO-1 and proliferative activity as measured by MIB-1 seems of no clinical value for the prediction of long-term survival in squamous cervical carcinoma. The predictive value of tumour angiogenesis for survival outcome has still to be determined in squamous cervical carcinoma.

Immunohistochemical expression of the mutant p53 protein and nuclear DNA content during the transition from benign to malignant breast disease.

Immunohistochemical expression of the cellular phosphoprotein p53 was investigated in archival, formalin-fixed, and paraffin-embedded surgical breast tissue specimens from 543 patients using the polyclonal antibody CM-1. Cytometric DNA assessments were performed on histopathologically or cytopathologically identified cell nuclei using image analysis. The series included five samples of normal resting breast parenchyma, 35 benign lesions including benign tumors, 54 hyperplastic lesions with and without atypia, 109 carcinomas in situ, and 340 invasive adenocarcinomas. In 56 of the latter cases specimens from corresponding lymph node metastases also were investigated. Mutant p53 protein expression was absent in normal resting parenchyma and in benign lesions, including benign tumors and epithelial hyperplasias. However, 14 of the 54 hyperplasias (26%) were found to be of DNA aneuploid type. Thirteen of 109 (12%) carcinomas in situ and 79 of 340 (23%) invasive neoplasms expressed the mutant p53 protein. Eight of nine (89%) p53 immunoreactive carcinomas in situ and 62 of 78 (80%) invasive carcinomas with p53 expression were DNA aneuploid. In invasive carcinomas p53 expression was absent in well differentiate neoplasms. In contrast, 58 of 158 (37%) poorly differentiated invasive carcinomas immuoreacted. Intraductal carcinomas of comedo type and poorly differentiated invasive carcinomas of comedo type expressed the mutant p53 protein in seven of 18 cases (39%) and in 14 of 22 cases (64%), respectively. The staining behavior of lymph node metastases was the same as that of the corresponding primary tumors. The present findings suggest that chromosomal alterations as indicated by DNA aneuploidy occur in precancerous lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Alterations of p53 and expression of WAF1/p21 in human thyroid tumors.

We have investigated p53 expression in 178 thyroid tumors from 162 patients by immunohistochemistry using two antibodies, DO1 and CM1. In addition, 35 tumors were analyzed for expression of WAF1/p21, one of the downstream mediators of p53. Only 15 tumors (8.4%) had greater than 10% of tumor cell nuclei positively stained for p53. Six of 14 Hürthle tumors and three of 34 papillary thyroid carcinomas showed staining of p53 in the cytoplasm. A total of 40 tumors, including all p53 positive tumors, and all anaplastic and poorly differentiated tumors were screened for mutations in exons 5-8 of the TP53 gene by constant denaturing gel electrophoresis and subsequent sequence analysis. A mutation was detected in five tumors only: one anaplastic carcinoma, one poorly differentiated follicular carcinoma (negative by p53 immunohistochemistry), one atypical follicular adenoma, and two papillary thyroid carcinoma metastases, of which the primary tumors had no detectable mutation. We conclude that p53 immunohistochemistry cannot be used for diagnostic and prognostic purposes in thyroid tumors. The tumors with TP53 mutation showed a markedly reduced WAF1/p21 expression. Three anaplastic carcinomas with highly expressed p53, but with no detectable mutation, also showed high expression of WAF1/p21. This may be explained by overexpression of wild-type p53, possibly due to the patients' preoperative treatment, including external radiation of the neck region. The results indicate that WAF1/p21 immunohistochemistry contributes to the information of the functional status of p53, and may facilitate the interpretation of results from p53 immunohistochemistry in these tumors.

Cancer of the vagina: Laminin-5gamma2 chain expression and prognosis.

The purpose of this experiment was to investigate the expression and the prognostic impact of the gamma2 subchain of laminin-5 in vaginal malignancies. The outcome of the rare disease primary carcinoma of the vagina is poor and little is known about prognostic markers. The gamma2 chain of laminin-5, an epithelial basement membrane protein, is thought to play a crucial role in tumor cell adhesion, migration, and proliferation, and may thus be an additive potential marker. Archival, paraffin-embedded sections were stained immunohistochemically with an antibody against the gamma2 chain of human laminin-5 protein. The material consisted of 59 cases of primary vaginal malignancies, subdivided into short- and long-time survivors. All invasive malignancies of epithelial origin were positively stained with the antibody against the gamma2 chain. High expression of the gamma2 chain correlated significantly in an univariate analysis with short-time survival (P = 0.041), but in the multivariate analysis only age and tumor size were independent prognostic factors. A significant intercorrelation between large tumors and high gamma2 chain immunoreactivity was found (P = 0.003). These results indicate that laminin-5gamma2 subchain expression in primary vaginal carcinomas is of prognostic impact. However, in a multivariate analysis only patient age and tumor size had independent prognostic value.

Evaluation of tissue and serum VEGF in patients with head and neck carcinoma.

Serum vascular endothelial growth factor (VEGF) was measured in 54 cancer patients with head and neck carcinoma. In addition, tumor VEGF was examined by immunohistochemistry in sections of biopsies obtained within 4 weeks to serum sampling in 37 of these patients. Serum VEGF levels were higher in the sera of the tumor patients than in the sera of healthy control subjects (P < 0.005). Patients with stage II-IV tumors showed increased levels of serum VEGF, whereas patients with stage I tumors did not. The receiver operating characteristics (ROC) of serum VEGF were similar to those observed with TPS (tissue protein specific antigen). Immunohistochemistry of tissue sections showed that 24/37 tumors were VEGF positive. No connection was observed between strong VEGF staining of tumor tissue sections and high levels of serum VEGF. We conclude that serum VEGF could be a useful marker for monitoring head and neck carcinoma patients, but that serum and tissue VEGF levels do not appear to correlate with each other.

Correlation between basic fibroblast growth factor immunostaining of stromal cells and stromelysin-3 mRNA expression in human breast carcinoma.

We examined the localization of basic fibroblast growth factor (bFGF) in a series of human breast carcinomas using immunohistochemistry. Staining was observed in tumour cells in 15 out of 54 (28%) tumours and in the adjacent stroma in 34 out of 54 (63%) tumours examined. No correlation was observed between positive staining of these two compartments. The relationship between bFGF staining and expression of the metalloprotease stromelysin-3, and between bFGF and microvessel density, was examined. A statistically significant correlation (P < 0.003) was observed between bFGF staining of the stromal compartment and high expression of stromelysin-3 (ST-3; MMP-11) metalloprotease mRNA by stromal cells. In contrast, no correlation was observed between bFGF and intratumour microvessel density (IMD). These results raise the possibility that bFGF may be involved in the induction of stromelysin-3 mRNA expression in breast cancer stroma.

Distinct deleted regions on chromosome segment 16q23-24 associated with metastases in prostate cancer.

Cadherins (CDH) are cell adhesion molecules and their dysfunctions have been implicated in the development of cancer metastases. Several cadherin genes are tandemly located on 16q, which is frequently deleted in prostate cancer. We therefore used 22 markers on 16q to localize important deleted regions in metastases of this tumor. We found 16q deletions in 24/32 (75%) tumors. All lymph node and brain metastases showed extensive deletions, while 52% of primary tumors displayed limited deletions. Commonly deleted regions (CDRs) on 16q23-24, CDR2 (D16S515-D16S516) and CDR4 (D16S520-D13S3028), were strongly associated with metastases and increased Gleason score. Reduced CDH1 (E-cadherin) expression was seen in 16/32 (50%) tumors, but the CDH1 gene is not within either of these two regions. Sequencing analysis for all 16 exons of the CDH1 gene did not reveal any mutations in 10 tumors, including three brain metastases with both 16q22.1 deletion and absent E-cadherin expression. Our results implicate other, yet unidentified genes on 16q23-24 to be the frequent targets of mutations and deletions in prostate cancer metastases.

Evaluation of retinoblastoma and Ki-67 immunostaining as diagnostic markers of benign and malignant parathyroid disease.

Assessment of the malignant potential of parathyroid tumors in the absence of metastases can be difficult using morphologic criteria alone. In this study we have examined a total of 58 parathyroid tumors (31 benign, 15 malignant, and 12 equivocal) from 54 patients using immunohistochemistry with monoclonal antibodies directed against the retinoblastoma (RB) protein and the cell cycle-associated antigen Ki-67 to evaluate their role as diagnostic markers. RB protein immunoreactivity was not useful for distinguishing between benign and malignant parathyroid tumors. Analysis of the proliferation marker Ki-67 showed that there was a trend toward more intense staining in the malignant cases. The Ki-67 labeling index was highest in the parathyroid cancers (median 33) and lowest in the sporadic primary adenomas (median 2). An observation that might have clinical implications is that tumors from patients with familial hyperparathyroidism linked to chromosome 1q showed a high Ki-67 index, indicating strong proliferative activity (median 25). This correlates well with the clinical observation of tumors with malignant potential in this syndrome. Because of the considerable overlap between groups of tumors, Ki-67 is not suitable for definitive differentiation between benign and malignant tumors. However, Ki-67 may give valuable information about which patients should be followed more closely.;1999>