HER-2/neu oncogene amplification by fluorescence in situ hybridization in epithelial tumors of the ovary.

HER-2/neu gene amplification and protein overexpression have been associated with prognosis in breast, lung and prostate cancers but have not been extensively studied in ovarian carcinoma. For the study, we selected 5-micron-thick, formalin-fixed, paraffin-embedded tissue sections from 74 cases of ovarian epithelial tumors of low malignant potential and ovarian carcinoma. Tumors were graded and staged and evaluated for amplification of the HER-2/neu gene by fluorescence in situ hybridization. HER-2/neu amplifications was present in 3 of 13 serous, mucinous, and endometrioid epithelial tumors of low malignant potential and in 40 of 61 epithelial carcinomas. In the carcinoma group, amplification did not correlate with stage, grade, or tumor type. Mean follow-up was 31 months; 1 patient with a low malignant potential tumor and 32 patients with carcinomas died of disease. On univariate and multivariate analysis, survival correlated with stage of disease but not with HER-2/neu amplification. HER-2/neu amplification by fluorescence in situ hybridization can be performed on tissue sections of ovarian neoplasms; amplification is uncommon in ovarian tumors of low malignant potential, but is present in 66% of ovarian epithelial carcinomas. HER-2/neu amplification did not predict outcome in ovarian epithelial neoplasia but may have an important role in tumor development.

Correlation of p34cdc2 cyclin-dependent kinase overexpression, CD44s downregulation, and HER-2/neu oncogene amplification with recurrence in prostatic adenocarcinomas.

PURPOSE: To test whether p34cdc2 overexpression, CD44s downregulation, and HER-2/neu amplification correlate with disease recurrence after radical prostatectomy, and to evaluate a possible biologic association between p34cdc2 and HER-2/neu expression. MATERIALS AND METHODS: Immunohistochemical (IHC) detection of both p34cdc2 cyclin-dependent kinase (CDK) and CD44s expression and fluorescence in situ hybridization (FISH)-based analysis of HER-2/neu gene status were performed on formalin-fixed, paraffin-embedded sections of 106 prostatic adenocarcinomas (PACs). Findings were correlated with Gleason grade, pathologic stage, DNA ploidy, and postsurgical biochemical disease recurrence. RESULTS: CDK overexpression correlated with tumor grade (P = .001), DNA ploidy (P = .001), pathologic stage (P = .04), and disease recurrence (P = .01). CD44s downregulation correlated with grade (P = .03), ploidy (P = .01), and recurrence (P = .02). HER-2/neu amplification correlated with grade (P = .001), ploidy (P = .001), and recurrence (P = .01). On multivariate analysis, CDK overexpression independently predicted recurrence (P = .001) after prostatectomy. CDK expression correlated with HER-2/neu status with 32 of 65 (49%) tumors that overexpressed CDK and showed concomitant HER-2/neu amplification (P = .04). CONCLUSION: This study showed that p34cdc2, CD44s, and HER-2/neu are variably expressed or amplified in prostatic carcinoma and that such alteration may affect tumor behavior. In addition, CDK overexpression and HER-2/neu amplification may be biologically related.

Identification of HER-2/neu oncogene amplification by fluorescence in situ hybridization in stage I endometrial carcinoma.

Prognostic factors capable of detecting potential for aggressive disease in early stage endometrial cancer might be useful in selecting patients for early adjuvant therapy. Sixty-three patients with surgical Stage I endometrial carcinoma treated by hysterectomy with a mean follow-up of 55 months were evaluated for tumor type, grade, depth of myometrial invasion, presence of vascular invasion, DNA ploidy, and HER-2/neu overexpression by immunohistochemical techniques. These results were compared with HER-2/neu gene amplifications evaluated by fluorescence in situ hybridization (FISH) and their ability to predict disease survival. For FISH, sections 5 microns thick of formalin-fixed, paraffin-embedded tissues were processed using the Oncor Chromosome In Situ Hybridization System. Automated hybridization using the Ventana Gen was performed with the Oncor unique sequence digoxigenin-labeled HER-2/neu DNA probe. Gene copy numbers were evaluated using the Zeiss Axioskop50 fluorescence microscope. HER-2/neu amplification was noted in 24 (38%) of 63 cases. By multivariate analysis, only aneuploidy (P = .04) and HER-2/neu amplification by FISH (P = .04) independently correlated with survival. Although we saw a relationship between HER-2/neu protein expression and gene amplification, this trend did not achieve statistical significance. HER-2/neu oncogene amplification can be assessed using automated FISH on formalin-fixed, paraffin-embedded tissue. HER-2/ neu amplification predicts poor outcome in Stage I endometrial cancer. HER-2/neu amplification status has potential use in the identification of patients with high risk of disease recurrence who might benefit from intensified therapy.

Telomerase activity in human benign prostate tissue and prostatic adenocarcinomas.

Telomerase adds a hexanucleotide telomeric sequence to the chromosomal ends during replication and is postulated to play a role in cellular senescence and immortalization. Thirty-four human prostate tissues (18 malignant; 16 benign) were analyzed for telomerase activity by a sensitive nonradioactive polymerase chain reaction (PCR)-based method using the TRAP-eze telomerase detection kit (Oncor, Inc., Gaithersburg, MD). Telomerase activity in the homogenized tissue extracts was correlated with tumor grade, pathologic stage, and DNA ploidy. Specimens that exhibited the 36 bp internal control band and a ladder of products with 6-base increments starting with 50 nucleotides were considered positive. Fourteen (78%) of 18 prostatic adenocarcinomas (PACs) and only 2 (13%) of 16 benign prostate tissues exhibited telomerase activity. Our results indicate that, in contrast to most benign prostate tissues, telomerase activity can be detected in the majority of PACs and appears to be independent of tumor grade, stage, or DNA ploidy. Telomerase expression is occasionally detected in benign prostatic tissues bordering PACs and may result from either the presence of undetected tumor foci in these stored specimens or the proliferative response of the benign elements to adjacent cancer.

HER-2/neu gene amplification status in prostate cancer by fluorescence in situ hybridization.

HER-2/neu expression has been established as a prognostic factor in breast and other cancers. In prostate cancer (PC), a similar predictive role has been hindered by variable immunohistochemical (IHC) results. The authors studied DNA amplification of the HER-2/neu gene on 4-microm sections obtained from 62 formalin-fixed, paraffin-embedded PCs by fluorescence in situ hybridization (FISH). The results were compared with HER-2/neu protein expression as determined by IHC and correlated by logistic regression analysis with Gleason tumor grade, DNA ploidy, serum prostate specific antigen (PSA), and pathological stage. The HER-2/neu gene was localized using the Oncor (Gaithersburg, MD) digoxigenin-labeled unique sequence probe. Amplified PCs had at least 20 malignant cells, with 5 or more copies of the sequence. Amplification of HER-2/neu correlated with Gleason score (P = .0001). The mean Gleason score of unamplified tumors was 5.7 and that of amplified tumors was 7.5. Nondiploid tumors had a significantly greater rate of HER-2/neu amplification compared with diploid tumors (P = .0003). Of the 62 cases evaluated by IHC and FISH, 18 cases (29%) were overexpressed by IHC, and 27 cases (44%) were amplified by FISH. A trend for similar HER-2/neu status in each PC by the two methods did not reach statistical significance (P = .23). HER-2/neu amplification by FISH was associated with advanced pathological stage; however, this relationship reached only near-statistical significance (P = .06). There was no correlation of HER-2/neu amplification by FISH with patient age or preoperative serum PSA levels. The authors conclude that HER-2/neu gene amplification status can be determined by FISH on archival prostate cancer specimens, significantly correlates with high tumor grade and nondiploid DNA content, and is more frequently encountered in tumors with advanced pathological stage. Also, FISH is more sensitive than IHC for detection of abnormalities in the HER-2/neu gene, and further studies should be undertaken to determine whether a FISH-based HER-2/neu detection method may prove of importance in the prediction of prognosis and planning of therapy in prostate cancer patients.

Telomerase activity in benign endometrium and endometrial carcinoma.

Telomerase, a ribonucleoprotein associated with synthesis of telomeric DNA, is postulated to play a role in cellular senescence and immortalization. Telomerase adds a hexonucleotide telomeric sequence to the chromosomal ends during replication and is preferentially expressed in most malignant and germ-line tissues but is usually undetectable in normal somatic cells. In the current study, 34 human endometrial tissues (20 malignant and 14 benign) were analyzed for telomerase activity by a nonradioactive PCR-based method using the TRAP-eze telomeric repeat amplification detection kit (Oncor). Nineteen of 20 (95%) endometrial carcinomas and 8 of 8 (100%) benign endometrial tissues from premenopausal women exhibited strong telomerase activity, whereas 6 of 6 (100%) benign endometrial tissues from postmenopausal women showed only weak telomerase activity. There was no correlation of telomerase activity with tumor grade, depth of invasion, or DNA content. Benign cycling endometrium, a rapidly proliferating tissue, features positive telomerase activity, although expression in nonneoplastic tissues has only rarely been previously reported. Only weak activity is detected in endometrial tissues after menopause, but telomerase activity can be strongly reactivated in patients who develop endometrial cancer.

Prognostic significance of HER-2/neu gene amplification status by fluorescence in situ hybridization of prostate carcinoma.

BACKGROUND: HER-2/neu gene amplification, established as a prognostic factor in breast carcinoma and other cancers, has not been correlated with outcome in prostate carcinomas (PCs). METHODS: HER-2/neu gene amplification was determined by automated fluorescence in situ hybridization (FISH) using a unique sequence cosmid probe on 113 formalin fixed, paraffin embedded 4-microns tissue sections and the results compared with tumor grade, DNA ploidy, HER-2/neu protein expression by immunohistochemistry (IHC), serum prostate specific antigen, pathologic stage, and postoperative disease recurrence (mean follow-up of 44 months). RESULTS: HER-2/neu gene amplification by FISH (41% of PCs) correlated with tumor grade (P = 0.001) and DNA ploidy status (P = 0.0003). HER-2/neu protein overexpression by IHC (29% of PCs) correlated with grade (P = 0.03), but not with DNA ploidy. A trend for similar HER-2/neu status in each PC by IHC and FISH did not reach statistical significance (P = 0.25). On univariate analysis, HER-2/neu amplification by FISH (P = 0.029), tumor grade (P = 0.013), and DNA ploidy (P = 0.016) correlated with postoperative disease recurrence. HER-2/neu expression by IHC did not correlate with outcome. On multivariate analysis, grade (P = 0.0001) and ploidy (P = 0.001) were independent outcome predictors; HER-2/neu amplification by FISH reached near-independent significance (P = 0.125). CONCLUSIONS: HER-2/neu gene amplification by FISH on archival PCs significantly correlates with grade and DNA ploidy status, is more sensitive than IHC in detecting HER-2/neu gene abnormalities, predicts postoperative disease recurrence, and may prove important in planning therapy for patients with prostate carcinoma.