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B V Kallakury

Publications and source records attributed to B V Kallakury.

At least 19 recordsLinked to original sources
PubMed1997

The prognostic significance of p34cdc2 and cyclin D1 protein expression in prostate adenocarcinoma.

BACKGROUND: Cyclin-dependent kinases (CDK) and cyclins constitute the subunits of the maturation-promoting factor that controls the process of cell division. High levels of these proteins have been reported in human malignancies of the stomach, colon, breast, and lung, and have been implicated in aberrant cell division and dysregulated tumor growth. METHODS: p34cdc2 CDK and cyclin D1 (D1) protein expression were evaluated in 140 radical prostatectomy specimens harboring adenocarcinoma (PAC), using the respective monoclonal antibodies on archival tissue sections. In each case, slides stained with hematoxylin and eosin were examined for evaluation of Gleason's grade and pathologic stage. The DNA content of the tumors was determined by the Feulgen method with the CAS200 Image Analyzer (Cell Analysis Systems, Lombard, IL). Nuclear immunoreactivity for the two proteins was semiquantitatively scored, and results were correlated with Gleason's grade, stage, ploidy, metastatic status, and disease recurrence after radical prostatectomy. RESULTS: p34cdc2 was expressed in 84 of 140 PACs (60%) and correlated with high Gleason's grade (P = 0.0001), advanced pathologic stage (P = 0.01), nondiploid DNA content (P = 0.0001), and metastases (P = 0.04). On multivariate analysis using the Cox proportional hazards model, p34cdc2 immunoreactivity (P = 0.0001) and high Gleason's grade (P = 0.01) each independently predicted disease recurrence. When tumors were of low Gleason's grade and lacked p34cdc2 expression, 4 of 39 PACs (10%) recurred, as compared with 18 of 47 (38%) that recurred when tumors were of high Gleason's grade and expressed p34cdc2 protein. D1 was positive in 31 of 140 PACs (22%) and showed a trend (P = 0.07) of high Gleason's grade, but it did not reach statistical significance with any of the prognostic variables. In the majority of PACs expressing both p34cdc2 and D1 proteins, the adjacent benign prostate acini showed focal, scattered nuclear positivity of the basal and secretory epithelial cells. CONCLUSIONS: p34cdc2 is expressed in a majority of PACs and correlates with high Gleason's grade, advanced pathologic stage, nondiploid DNA content, and metastases. On multivariate analyses high Gleason's grade and p34cdc2 immunoreactivity predict disease recurrence independently of the pathologic stage. Thus, p34cdc2 appears to play a critical role in the evolution, proliferation, and spread of PACs and may be of prognostic value when applied to initial prostate tissue samples taken by needle biopsy.

Adenocarcinoma↗
PubMed1997

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.

Adult↗
PubMed1997

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.

Adenocarcinoma↗
PubMed1997

Expression of CD44 standard form and variant isoforms in non-small cell lung carcinomas.

CD44, a cell adhesion molecule, has been implicated in tumor invasion and metastasis in certain malignancies. We studied the expression of CD44 standard (CD44s) and variant isoforms (CD44v) in 98 non-small cell lung carcinomas (NSCLCs) by immunohistochemistry and correlated the observations with clinical outcome. Formalin-fixed, paraffin-embedded archival tissues from 49 squamous cell carcinomas (SCCs) and 49 adenocarcinomas (ACs) were immunostained after microwave irradiation with monoclonal antibodies against CD44s and CD44v3, v4/5, v6, v7/8, and v10, and the results were correlated with histological tumor type, tumor stage, recurrence, and survival rates. SCCs of the lung showed strong membranous expression of each of the CD44s, v3, v4/5, v6, and v10 proteins in comparison with ACs (P < .0001). Staining for CD44 v4/5 was overwhelmingly positive in SCCs (72%) as compared with ACs (2.2%). Intense immunoreactivity for CD44v6 was present in 19 of 20 (95%) metastatic lung carcinomas. The bronchiolar basal cells and alveolar pneumocytes were positive for CD44s, v3, and v6. CD44s and variant isoform expression did not correlate with tumor stage, recurrence, and survival rates. In conclusion, there is significant immunopositivity of CD44s and variant isoforms in SCCs over ACs of the lung. Expression of CD44v6 may suggest an increased risk for local lymph node metastasis in NSCLCs. CD44v4/5 reactivity may be useful to discriminate squamoid differentiation in poorly differentiated NSCLCs.

Adult↗
PubMed1997

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.

Adult↗
PubMed1997

Coexistence of granular cell tumor and ipsilateral infiltrating ductal carcinoma of the breast.

Granular cell tumor is a benign neoplasm that is rarely seen in the breast and can mimic carcinoma, both clinically and by gross pathologic examination. The coexistence of a granular cell tumor with a primary mammary carcinoma can potentially pose diagnostic and therapeutic problems. In this report, we document a granular cell tumor of the breast coexisting with an ipsilateral infiltrating ductal carcinoma in a 74-year-old woman and discuss its clinical significance.

Aged↗
PubMed1997

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.

Adenocarcinoma↗
PubMed1996

Decreased levels of CD44 protein and mRNA in prostate carcinoma. Correlation with tumor grade and ploidy.

BACKGROUND: CD44, a transmembrane protein, is associated with cell-cell and cell-matrix interaction and with tumor growth and metastasis. Expression of both standard form and variant isoforms of CD44 protein has been associated with aggressive behavior and metastasis in various tumors, but has not been characterized in prostate adenocarcinoma (PAC). METHODS: The expression of CD44 standard (CD44s) and splice variant v3, v4/5, v6, v7/8, and v10 proteins were studied in 109 PACs and correlated with tumor grade, DNA ploidy, and mRNA levels. Monoclonal antibodies against the various CD44 proteins were applied to microwave irradiated, formalin fixed, paraffin embedded sections. The DNA content of the tumors was evaluated by the Feulgen method with the CAS200 Image Analyzer. Total RNA exhibiting 18s and 28s bands was derived from two benign prostatic tissues and 5 PACs exhibiting decreased levels of CD44 protein by immunohistochemistry. The RNA was analyzed with reverse transcriptase polymerase chain reaction using CD44 specific primers. RESULTS: The basal cells of the benign prostatic acini revealed uniform membranous staining for CD44s, v3, and v6 in 95-97% of cases. Similar staining was observed for v4/5, v7/8, and v10 in 40%, 30%, and 2% of cases, respectively. Secretory epithelial cells of the benign prostatic acini showed predominant expression of CD44s (97% of cases). Staining for CD44 variant proteins (v3, v4/5, v6, v7/8, and v10) in this location ranged from 9-22% of cases. Approximately 70% of the PACs showed significant loss of CD44s expression, which correlated with high tumor grade (Gleason > or = 7) (P = 0.01) and aneuploid status (P = 0.002). In 93-98% of the PACS, there was a complete lack of membranous expression for all CD44 variant isoforms. The metastatic PACS did not show preferential expression of either the standard form or any variant isoform. The cDNA from the normal prostates yielded a prominent CD44 standard form polymerase chain reaction product at 482 base pair (bp) and variant isoforms at approximately 650 and 850 bp. No CD44 products could be amplified from the subset of five PAC cDNAs, even when present at four-fold excess. CONCLUSIONS: PACS exhibit down-regulation of CD44 protein expression, which correlates with high tumor grade and aneuploidy. v6 and v3 isoforms were preferentially expressed in the basal cells of benign prostatic acini. Based on a subset of cases, loss of CD44 protein expression is associated with decreased abundance of CD44 mRNA.

Adenocarcinoma↗
PubMed1996

Cytokine, cell adhesion receptor, and tumor suppressor gene expression in vulvar squamous carcinoma: correlation with prominent fibromyxoid stromal response.

In a previous report, we observed by light microscopy the extracellular matrix in 51 vulvar squamous carcinomas and found that some tumors has a prominent stromal response in the form of a regional or diffuse zone of extracellular myxoid matrix containing immature collagen and fibroblasts at the tumor-stromal junction. These tumors were associated with clitoral involvement, ulcerative nonexophytic growth pattern, older age groups, poorer survival rate, and more extensive lymph node metastases than when prominent fibromyxoid stromal response (PFSR) was absent. This behavior was demonstrated despite the fact that these tumors were not larger, more deeply invasive, or of higher grade than when PFSR was absent. In the current immunohistochemical study, we examined cytokine, cell adhesion receptor, and tumor suppressor gene expression in 50 vulvar squamous carcinomas using a panel of antibodies to identify any potential role of these proteins in the development of a PFSR. Semiquantification of expression into none, focal (< 25% of cells showing expression), regional (25-50%), and diffuse (> 50%) patterns revealed PFSR to be statistically associated with high CD44, transforming growth factor (TGF) beta 3, and p53 protein expression, but not with fibroblast growth factor, epidermal growth factor, epidermal growth factor receptor, or E-cadherin expression. When expression of CD44 and either stromal or tumor TGF-beta 3 expression was high, i.e., regional or diffuse in distribution, 15 (50%) of 30 cases were associated with PFSR. In contrast, only 1 (7%) of 14 cases was associated with PFSR when expression was high for only one of these two proteins and none of 3 cases was associated with response when expression was low for both proteins (p = 0.005). Furthermore, in cases showing high expression for both TGF-beta 3 and CD44, PFSR was found in 13 (72%) of 18 cases when p53 expression was diffuse compared with 2 (17%) of 12 cases when expression was less (p = 0.01). Since TGF-beta acts mitogenically for fibroblasts and has been shown to be an inhibitor of epithelial cell growth, its high expression in a carcinoma with PFSR would suggest loss of effect on the epithelial component but an intact effect on the stroma. Since CD44 is known to act as a receptor for hyaluronic acid, which is a prominent stromal component and known to play an important role in cell mobility and tumor aggressiveness, its high expression in association with PFSR would suggest a role of CD44 overexpression in altered hyaluronate metabolism with accelerated tumor cell migration and subsequent distal spread. The current study demonstrates that alterations in cytokine and cell adhesion receptor status variably occur in vulvar squamous carcinoma and that such alterations may affect tumor morphology and behavior.

Carcinoma, Squamous Cell↗
PubMed1996

Increased bcl-2 protein levels in prostatic adenocarcinomas are not associated with rearrangements in the 2.8 kb major breakpoint region or with p53 protein accumulation.

bcl-2, an inhibitor of programmed cell death (apoptosis), is present in high levels in a subset of prostatic adenocarcinomas. In this study, 42 prostatic adenocarcinomas were analyzed to determine whether increased bcl-2 levels are associated with rearrangements in the 2.8-kb major breakpoint region, an association known to occur in certain follicular lymphomas featuring a t(14:18) translocation. Immunostaining for bcl-2 and p53 proteins was performed on formalin-fixed, paraffin-embedded tumor specimens using murine anti-human bcl-2 and p53 monoclonal antibodies in all 42 cases. Genomic DNA from paired frozen samples of each tumor was subjected to digestion with HindIII and EcoRI and the products analyzed on a Southern blot with a 2.8-kb-digoxigenin-labeled major breakpoint region probe. Comparisons between groups were evaluated with the Fisher exact test. Diffuse, strong cytoplasmic immunoreactivity for bcl-2 was present in the epithelial cells of tumor glands in 16 of 42 cases (38%), including 8 of 19 low grade (Gleason score 6 and below) and 8 of 23 high grade (Gleason score 7 and above) prostatic adenocarcinoma. Southern blotting demonstrated a normal 2.8-kb germline DNA fragment in every case, with no evidence of rearrangement. Nuclear p53 staining was present in 10 of 24 high grade and 0 of 18 low grade tumors (P < 0.001). Only four cases exhibited positivity for both bcl-2 and p53, and there was no association of bcl-2 positivity with co-expression of the p53 protein (P = 0.58). We conclude that aberrations in the function of either bcl-2 or p53 could possibly modify the apoptotic pathway resulting in the extended survival of tumor cells. Also, increased bcl-2 levels in prostatic adenocarcinomas occur in the absence of detectable rearrangements in the major breakpoint region.

Adenocarcinoma↗
PubMed1996

Expression of the CD44 cell adhesion molecule in urinary bladder transitional cell carcinoma.

CD44 cell adhesion molecule (PgP-1, ECM III, Hermes antigen) is a polymorphic integral membrane glycoprotein associated with cell matrix adhesion, lymphocyte activation, recirculation, and homing. CD44 expression has been reported in in malignant lymphoma and in a variety of epithelial human cancers but has not been studied as a prognostic marker in urinary bladder transitional cell carcinoma. CD44s (standard 85- to 95-kDa macromolecule) expression was measured by qualitative and image analysis-quantitated immunohistochemical techniques using the A3D8 monoclonal antibody. CD44v6 (a splice variant exon of CD44s) expression was measured by qualitative immunohistochemical techniques using the 2F10 monoclonal antibody. The results of CD44s and CD44v6 expression were compared with tumor grade, pathologic stage, and DNA content analysis on Feulgen-stained tissue sections in 44 cases of urinary bladder transitional cell carcinoma. The mean percentage-positive area of staining intensity for CD44s expression in Grade 1 tumors was 61%, compared with 30% for the Grade 3 tumors (P < 0.001). Non-invasive tumors featured a 59%-positive area of staining intensity, compared with the 30% staining percentage for the deeply invasive tumors (P < 0.001). There was significant correlation of aneuploid DNA content with loss of CD44s staining (P < 0.05). The staining results for CD44v6 paralleled those for the CD44s, with a significant loss of staining in high-grade and high-stage aggressive tumors in comparison with the low-grade nonaggressive tumors (P < 0.01). In urinary bladder transitional cell carcinoma, CD44s and CD44v6 expression parallels that for other cell adhesion molecules, such as E-cadherin, that feature a significant progressive loss of immunoreactivity in association with tumor dedifferentiation, advancing pathologic stage, and abnormal DNA content.

Adult↗
PubMed1996

MDM2 and p53 protein expression in the histologic subtypes of endometrial carcinoma.

The frequency of p53 protein overexpression differs among the histologic subtypes of endometrial carcinoma, from 21 to 48% in endometrioid carcinoma but from 80 to 86% in papillary serous carcinoma. Although p53 gene mutation can closely correlate with p53 protein overexpression in papillary serous carcinomas, high expression of p53 protein may also occur without detectable gene mutation in endometrioid carcinomas. Because MDM2 protein can bind mutant and wild-type p53 protein, we examined MDM2 and p53 protein expression in 27 endometrioid carcinomas and compared their expression patterns with those of 25 uterine papillary serous carcinomas. We detected p53 protein in 14 (52%) of the 27 endometrioid carcinomas but in 21 (84%) of the 25 papillary serous tumors (P = 0.02). MDM2 expression was more commonly detected in the endometrioid carcinomas. Nineteen (70%) of the 27 cases showed expression compared with 9 (36%) of the 25 papillary serous carcinomas (P = 0.03). p53 Expression correlated closely with MDM2 expression in endometrioid carcinomas but not in the papillary serous carcinomas. In endometrioid carcinomas, MDM2 was detected in 13 (93%) of 14 p53-positive carcinomas but in only 6 (46%) of 13 p53-negative tumors (P = 0.01). In papillary serous carcinomas, MDM2 was detected in 9 (43%) of 21 p53-positive carcinomas but in none of the 4 p53-negative tumors (P value not significant). These findings suggest that although high rates of p53 protein overexpression are most frequently associated with p53 gene mutation in uterine papillary serous carcinoma, p53 protein overexpression in endometrioid carcinoma is frequently associated with MDM2 overexpression. The selective correlation of MDM2 expression with p53 expression in endometrioid carcinomas but not in papillary serous carcinomas suggests an active role for MDM2 in binding and inactivating p53 in endometrioid carcinomas, leading to its overaccumulation and potentially impeding repair to damaged DNA. Additional study as to the cause of increased MDM2 expression in endometrial carcinoma, e.g., gene amplification, enhanced translation, or rearrangement, is indicated.

Adenocarcinoma↗
PubMed1995

Nuclear p53 immunoreactivity in papillary thyroid cancers is associated with two established indicators of poor prognosis.

The tumor suppressor protein, p53, protects somatic cells against the accumulation of genomic alterations. Cells harboring mutant or inactivated wild-type p53 protein are at risk for the development of genomic instability. Nuclear accumulation of p53 protein is associated with the stepwise dedifferentiation of papillary carcinoma. We asked whether nuclear p53 accumulation is associated with two known indicators of poor prognosis in papillary carcinoma. We studied 55 consecutive papillary cancers (28 from Russia, and 27 from upstate New York). Nuclear p53 immunoreactivity was assessed using a monoclonal antibody, DO-1, on Formalin-fixed paraffin-embedded specimens. The DNA index was determined by computerized image analysis of Feulgen-stained sections. Nearly all cases were well differentiated and none were associated with distant metastases or extrathyroidal invasion. All primary lesions were less than 4 cm in diameter, and almost all patients were female. Nuclear p53 immunoreactivity was associated with a high-risk group characterized by two known indicators of poor prognosis: age > 50, aneuploid DNA content, or both. In the high-risk group (N = 24) 33% of cases displayed nuclear p53 positivity, compared with only 6% in a low-risk group (N = 31) which lacked both features (P = 0.015, two-tailed Fisher exact test). Nuclear accumulation of immunoreactive p53 protein is associated with two established indicators of poor prognosis in papillary carcinoma of the thyroid. This result is consistent with the idea that aberrations in p53 function are associated with the stepwise loss of differentiation in this cancer.

Adolescent↗
PubMed1995

p53 gene status in endometrial carcinomas showing diffuse positivity for p53 protein by immunohistochemical analysis.

Although detection of p53 protein by immunohistochemical testing was originally thought to indicate p53 gene mutation, recent analyses of human malignancies have shown that high expression of p53 protein may occur without detectable gene mutation. Several explanations have been proposed for this phenomenon, including mutation out of "hot spot" regions, overexpression of wild-type protein, sampling error in molecular analyses, and conformational changes of wild-type p53 protein. As discussed, it is unlikely that the first two possibilities contribute significantly to the occurrence of this phenomenon, and the current study examined the possibility that sampling error in molecular analyses might account for a lack of concordance between immunohistochemical and molecular analyses. Such a possibility exists because immunohistochemical studies frequently report high expression when staining is only focal or regional and molecular analyses are based on the polymerase chain reaction, which is highly exponential in nature and may not detect mutation if the target gene segment is not amplified early in the chain reaction. In the current report, p53 protein expression was examined by immunohistochemical testing in 45 cases of endometrioid carcinoma, and all cases showing diffuse positivity were then examined by polymerase chain reaction in combination with single-strand conformational analysis for exons 4 to 9 with the use of a microdissection technique to separate malignant from benign cells. Of the 45 cases, diffuse staining was found in four cases, and only two of the four were found to show evidence of gene mutation.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1994

Observations on tumor and metastatic suppressor gene status in endometrial carcinoma with particular emphasis on p53.

BACKGROUND: Genetic changes in the development of endometrial carcinoma have not been characterized, and little is known of tumor or metastatic suppressor gene status in these malignancies. The current study on endometrioid carcinoma was undertaken to examine the status of two tumor suppressor genes that frequently have been found to be altered in human malignancies (the p53 gene and the retinoblastoma [Rb] gene) and to examine the status of the candidate metastatic suppressor gene, nm23-H1. METHODS: The status of the p53 gene was studied by immunohistochemistry of formalin-fixed paraffin-embedded biopsy samples from 72 patients with atypical endometrial hyperplasia or endometrioid carcinoma who underwent hysterectomy immediately after biopsy and from 5 patients with benign endometria. A search for loss of heterozygosity (LOH) of the nm23 gene after DNA extraction from frozen tissues and hybridization with nm23-H1 cDNA specific probe was made in 10 endometrial carcinomas. Rb gene status was evaluated by image analysis quantification of immunoreactive retinoblastoma protein in frozen sections of 10 carcinomas and 2 benign endometria. RESULTS: p53 expression was low in all benign endometria, but high expression was found in 2 (15%) of 13 atypical hyperplasias and in 23 (39%) of 59 carcinomas. High levels of p53 expression in endometrioid carcinoma correlated with the spread of disease outside of the uterus and by logistic regression, the presence of squamous differentiation, nuclear grade, and high p53 expression in the biopsy all independently correlated with spread of disease outside of the uterus. Although 7 of the 10 carcinomas studied were informative, LOH for the nm23 gene was not seen in any, including a site of metastasis. Rb protein expression in endometrial carcinoma was similar to expression in benign endometria. CONCLUSIONS: Although this study found no evidence of nm23-H1 gene alteration or alterations in Rb protein levels in endometrial carcinoma, high expression of p53 protein was sporadically identified in biopsy specimens of atypical hyperplasia and frequently found in endometrioid carcinomas. Determination of p53 expression in combination with the presence or absence of squamous differentiation and nuclear grade in biopsy material may help predict spread of endometrioid carcinoma outside the uterus and facilitate therapeutic planning before hysterectomy.

Adult↗
PubMed1994

Preferential expression of the cell adhesion molecule CD44 in papillary thyroid carcinoma.

CD44 is a polymorphic family of immunologically related integral membrane glycoproteins associated with cell matrix adhesion, lymphocyte activation and targeting, and tumor growth and metastasis. We studied CD44 expression in 114 formalin-fixed paraffin-embedded thyroid tumors using the A3D8 anti-human CD44 monoclonal antibody. Sixty-five of 67 papillary carcinomas (97%) strongly expressed CD44 with an intense plasma membrane pattern. Thirty-seven of these cases originated from Albany, New York, and 30 cases from Russia. Immunoreactivity was also observed in 9 of 16 follicular adenomas (56%); 4 of 8 Hurthle cell neoplasms (50%); 5 of 15 medullary carcinomas (33%); and 3 of 8 follicular carcinomas (38%). These results show that among thyroid neoplasms, papillary carcinomas preferentially display the CD44 antigen (P < or = 0.001). Nonneoplastic follicular epithelium exhibited a low to moderate level of staining. To further characterize the CD44 isoform, we tested a subset of cases with the 2F10 anti-human CD44 variant 6 monoclonal antibody, which recognizes a CD44 variant exon (CD44v6) implicated in tumor metastasis. Eleven of 11 papillary carcinomas tested were 2F10 positive, and 1 of the follicular carcinomas was positive. These results suggest the hypothesis that deregulated CD44v6 expression on the plasma membrane of papillary carcinoma cells contributes to the ability of those cells to metastasize to regional lymph nodes and then to remain dormant for years. Our results suggest that human papillary thyroid cancer will be an interesting model in which to further study the role of CD44 isoforms, particularly those containing CD44v6, in tumor metastasis and lymphatic invasion.

Antibodies, Monoclonal↗
PubMed1994

Association of p53 immunoreactivity with high gleason tumor grade in prostatic adenocarcinoma.

To determine whether p53 immunoreactivity correlates with the Gleason tumor grade in primary adenocarcinoma of the prostate we analyzed 107 consecutive surgical specimens (78 radical prostatectomies and 29 transurethral resections). A hematoxylin-eosin-stained slide from a representative block of each tumor was examined, and primary and secondary Gleason scores were assigned in each case. Additional paraffin sections from the same block were stained immunohistochemically for p53 expression using the monoclonal antibody clone DO-1, a mouse IgG2a directed against a denaturation-resistant epitope of p53. Four of 54 (7.4%) low-grade tumors (combined Gleason score of 6 and below) and 11 of 53 (20.8%) high-grade tumors (combined Gleason score of 7 and above) revealed strong nuclear positivity for p53. When evaluated using only the primary Gleason score, none of 23 (0%) Gleason grade 2 tumors and 15 of 84 (17.9%) Gleason grade 3 or higher tumors were positive. These data demonstrate a positive association between p53 immunoreactivity and higher Gleason grade tumors (P = .04 for the combined score, P = .02 for primary score only). In addition, we noted occasional p53-positive nuclei in basal cells of benign glandular acini in regions flanking tumor. Focally positive nuclear staining also was demonstrated in basal cells from nine of 25 prostate glands exhibiting benign prostatic hyperplasia with no tumor. These results suggest that p53 overexpression might be associated with the known proliferative capacity of basal cells in benign hyperplastic prostate glands, and that mutations of p53 might play a role in the pathogenesis of a subset of high-grade prostate adenocarcinomas.

Adenocarcinoma↗