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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We optimized the assay for detection of cytokeratin 19 (CK19) mRNA by the reverse transcriptase-polymerase chain reaction (RT-PCR) in blood as an index of circulating tumor cells in breast cancer patients. The limit of detection of < 1 MCF7 tumor cells per 10(6) peripheral blood leukocytes (PBL) was achieved in mixing experiments. We did not detect CK19 mRNA in control bloods (0/30) or in the blood of patients with benign breast disease (0/15). In blood samples from 109 patients with invasive breast cancer, CK19 mRNA was detected in 7/23 patients with node-negative disease, in 21/58 with node-positive disease, and in 20/28 with distant metastases. There was a significant association (P < 0.01) of CK19 positivity with distant metastatic versus both node-negative and node-positive disease, but not with any other histopathological parameter examined. In a small number of patients with distant metastases, increased intensity of the CK19 RT-PCR signal was associated with a reduced survival.
Breast Cancer Res Treat 2000 Mar
PMID:RT-PCR amplification of CK19 mRNA in the blood of breast cancer patients: correlation with established prognostic parameters. 1084 77

The presence of axillary lymph node metastasis in patients with breast cancer is a major prognostic factor and also determines the use of adjuvant chemotherapy. Micrometastasis has been arbitrary defined as deposits of < 2 mm dimension. Earlier studies of micrometastases failed to demonstrate prognostic relevance. However, when larger numbers of patients were followed up for longer periods, micrometastasis was shown to be a significantly poor prognostic parameter with patients having a survival rate similar to those with macrometastasis or nodal disease. There are no compelling reasons to retain the term "micrometastasis" in the light of these findings and our understanding of tumor biology. Routine histological examination of axillary lymph nodes is a notoriously inaccurate method for the detection of metastases. When serial or multilevel sectioning and/or immunohistochemical staining for cytokeratin were employed, detection rates increased by as much as 33%. Reverse transcriptase-polymerase chain reaction and Southern blotting for CK19 may be a more accurate method of examination. However, there are inherent technical problems associated with this method, and the recent finding of a pseudogene with great homology to CK19 in normal peripheral blood nucleated cells further emphasises the need for caution in this approach. It is not cost-effective to employ serial sectioning and immunohistochemistry when examining the axillary contents. However, the introduction of sentinel-node biopsy may allow detailed examination of the single node most likely to harbour a metastatic tumor.
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PMID:The prognostic dilemma of nodal micrometastases in breast carcinoma. 1089 73

Various molecular markers have been used for the detection of circulating breast cancer cells in blood by reverse transcriptase-polymerase chain reaction (RT-PCR). Using nested RT-PCR, we compared the specificity and sensitivity of human mammaglobin (hMAM), epidermal-growth-factor receptor (EGF-R), and cytokeratin 19 (CK-19) expression as markers for circulating carcinoma cells in the peripheral blood of patients with breast cancer. Blood samples from 12 patients with ductal carcinoma in situ, 133 patients with invasive breast cancer, 20 patients with hematological malignancies, 31 healthy volunteers, and tumor tissues from 40 patients with invasive breast cancer were screened for mRNA encoding hMAM, EGF-R, or CK-19 by nested RT-PCR. In all breast cancer tissues, mRNA for hMAM, EGF-R, and CK-19 was detectable. In blood samples from patients with invasive breast cancer, 11 (8%), 13 (10%), and 64 (48%) were positive for mRNA encoding hMAM, EGF-R, or CK-19, respectively. Blood samples from none of the healthy volunteers and patients with hematological disorders were positive for hMAM, while CK-19 mRNA was found in the blood of 12 (39%) healthy volunteers and transcripts for EGF-R and CK-19 were detectable in 5 (25%) and 2 (10%), respectively, of the patients with hematological malignancies. Only hMAM mRNA expression in blood correlated with clinical parameters such as nodal status, metastasis, and CA 15-3 serum levels. In summary, hMAM transcripts detectable in blood by RT-PCR represent the most specific molecular marker for hematogenous spread of breast cancer cells. With the nested RT-PCR method, aberrant EGF-R mRNA expression might occasionally be found in hematological malignancies, whereas CK-19 mRNA expression proved to be rather nonspecific. The prognostic value of hMAM RT-PCR-based tumor cell detection in peripheral blood should be further tested and validated in prospective studies.
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PMID:Mammaglobin gene expression: a superior marker of breast cancer cells in peripheral blood in comparison to epidermal-growth-factor receptor and cytokeratin-19. 1090 52

Human mammary epithelial cells from reduction mammoplasties were serially propagated in vitro from single cells and/or cell clusters using the NIH 3T3 cell feeder layer technique. In seven passages 46 cell population doublings, corrected for plating efficiency were achieved. The plating efficiency of epithelial cells in the primary culture was 0.2%. During subsequent passages it rose to 10-12% and decreased sharply towards the end of the culture life. In the third and fourth passages temporal prevalence of luminal cells was observed. The critical conditions for prevalence of the luminal phenotype were found to be the initial dissociation and optimum seeding density during subculturing. In primary cultures, after optimum dissociation of 0.15 cm3 mammary tissue with 0.05% collagenase A (Boehringher-Mannheim) in Eagle's MEM for 16 h at 37 degrees C, the yield on day 13 was 20 large colonies of 8-10 mm diameter. About 30% of the epithelial cells, which stained positively for the luminal cell marker cytokeratin 19, occupied colony centres. The remaining 70% were actin positive myoepithelial cells at the periphery. In subsequent passages, when using the optimum seeding density of 2 x 10(5) cells per 60 mm culture dish, the proportion of luminal cells gradually increased to 90% on day 35 in the fourth passage. A sudden rise in the proportion of rapidly growing myoepithelial cells to 65% was observed in the fifth passage. In the sixth and seventh passage small colonies were formed, most of which contained at least one keratin-19-positive (luminal) cell. Cells of human breast carcinomas are considered to be of luminal origin. Therefore, the described approach can be useful in studies of cell and molecular biology of mammary carcinomas.
Breast Cancer Res Treat 2000 Apr
PMID:Temporal in vitro expansion of the luminal lineage of human mammary epithelial cells achieved with the 3T3 feeder layer technique. 1093 Jan 12

Amplification of cytokeratin 19 (CK19) transcripts by reverse transcriptase-polymerase chain reaction (RT-PCR) has been shown to be a highly sensitive assay for the detection of bone marrow micrometastases (BMM) of breast cancer, but recent studies have demonstrated the occurrence of false-positive results due to low-level, illegitimately transcribed CK19 in normal bone marrow tissue. One approach to solve this problem is to develop a quantitative CK19 RT-PCR assay and to introduce a cut-off value which can distinguish between illegitimate expression and cancer-specific expression levels. In the present paper, we describe a quantitative CK19 RT-PCR assay using a real-time automated PCR system. The number of CK19 transcripts was normalized to that of GAPDH transcripts as an internal control for quality and quantity of cDNA. The cut-off value for the ratio of CK19 to GAPDH transcripts was set at 10(-4) since the ratio never exceeded this value in the control bone marrow samples (n = 12). In total, 117 bone marrow aspirates from stage I - III patients with invasive breast cancers were subjected to CK19 RT-PCR assay and immunocytological examination. Forty (34.2%) were found to be BMM-positive by CK19 RT-PCR assay whereas only three (2.6%) were found to be BMM-positive by immunocytology. Multivariate analysis has shown that occult BMM detected by CK19 RT-PCR is a significant risk factor for relapse, being independent of axillary lymph node metastases.
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PMID:Prognostic significance of occult bone marrow micrometastases of breast cancer detected by quantitative polymerase chain reaction for cytokeratin 19 mRNA. 1101 Nov 20

Mortality among patients with breast cancer (BC) is mainly caused by metastasis. We determined the circulating tumor burden in BC patients by semiquantitative reverse transcription-polymerase chain reaction using carcinoembryonic antigen (CEA) and cytokeratin 19 (CK19) mRNAs as molecular markers. We distinguished the mRNA levels in circulation between BC patients and healthy controls with reference to a BC-derived cell line, SK-BR-3. We prospectively analyzed peripheral blood samples from 33 BC patients and 26 healthy controls. We found CEA mRNA in 97% of patients and 92% of normal controls, and CK19 mRNA in 72% of patients and 19% of controls. CEA and CK19 mRNAs in normal peripheral blood were most likely derived from illegitimate transcription. In 10 patients, of whom 9 (90%) developed systemic metastases, the upper limit of CK19 mRNA of normal controls was exceeded. As compared with normal controls, significantly elevated CK19 mRNA levels in the patients appeared to originate from circulating malignant BC cells (P<0.0001). It was clinically significant that the mean CK19 mRNA level increased with advancing disease stage. Of prognostic value, we report for the first time that BC patients with CK19 mRNA elevation had notably shorter (approximately 3-year reduction) overall survival than patients with normal CK19 mRNA levels (P=0.045). Quantification of CK19 mRNA may prove useful for cancer staging, disease monitoring and prognostic assessment among BC patients.
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PMID:Quantitative correlation of cytokeratin 19 mRNA level in peripheral blood with disease stage and metastasis in breast cancer patients: potential prognostic implications. 1117 98

RT-PCR assay for multiple markers has been shown to increase the detection rate of circulating tumor cells. This assay targeted against cytokeratin 19 (CK19), cytokeratin 20 (CK20) and beta-subunit of human chorionic gonadotropin (beta-hCG) was used to detect circulating breast cancer cells. 5 ml of peripheral blood was drawn before any surgical procedures from 72 breast cancer patients and 30 cases with benign breast disease. Total RNA was extracted from peripheral blood mononuclear cells, reverse-transcripted and amplified. For the benign cases, 10% (3/30) were positive for CK19 and all were negative for CK20 and beta-hCG, whereas 9.72% (7/72), 2.78% (2/72) and 12.5% (9/72) of the malignant cases were positive for CK19, CK20 and beta-hCG respectively. The detection rate of circulating breast cancer cells was unchanged when CK19 was combined with CK20, but it increased to 18.1% (13/72) when the marker was combined with beta-hCG. A significant difference was observed for beta-hCG between benign cases and affected patients with stage II, III and IV disease (p = 0.026). In conclusion, positive RT-PCR signals in blood samples of affected patients correlated with stage, in particular for beta-hCG. CK19/beta-hCG was a promising marker combination.
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PMID:Detection of circulating breast cancer cells with multiple-marker RT-PCR assay. 1129 72

Real-time RT-PCR is a relatively new technology that uses an online fluorescence detection system to determine gene expression levels. It has the potential to significantly improve detection of breast cancer metastasis by virtue of its exquisite sensitivity, high throughput capacity and quantitative readout system. To assess the utility of this technology in breast cancer staging, we determined the relative expression levels of 12 cancer-associated genes (mam, PIP, mamB, CEA, CK19, VEGF, erbB2, muc1, c-myc, p97, vim and Ki67) in 51 negative-control normal lymph nodes and in 17 histopathology-positive ALNs. We then performed a receiver operating characteristic (ROC) curve analysis to determine the sensitivity and specificity levels of each gene. Areas under the ROC curve indicated that the most accurate diagnostic markers were mam (99.6%), PIP (93.3%), CK19 (91.0%), mamB (87.9%), muc1 (81.5%) and CEA (79.4.0%). mam was overexpressed in 16 of 17 lymph nodes known to contain metastatic breast cancer at levels ranging from 22- to 2.8 x 10(5)-fold above normal mean expression, whereas PIP was overexpressed from 30- to 2.2 x 10(6)-fold above normal in 13 lymph nodes. Real-time RT-PCR analysis of pathology-negative LN from breast cancer patients revealed evidence of overexpression of PIP (6 nodes), mam (3 nodes) and CEA (1 node) in 8 of 21 nodes (38%). Our results provide evidence that mam, PIP, CK19, mamB, muc1 and CEA can be applied as a panel for detection of metastatic and occult micrometastatic disease.
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PMID:Quantitative real-time RT-PCR detection of breast cancer micrometastasis using a multigene marker panel. 1141 Aug 61

The identification of specific tumor mRNA markers by reverse transcription-polymerase chain reaction might be a valuable diagnostic adjunct for the detection of breast cancer metastases in axillary sentinel lymph nodes (SLNs). In this study we have compared the diagnostic accuracy of an extensive histopathologic examination of 146 SLNs from 123 breast carcinoma patients with that of the evaluation of 5 mRNA markers. When analyzed individually, none of the different markers attained a sensitivity higher than 77.8%, and the general concordance with the histopathologic findings ranged from 78.8 to 83.6%. In a multiple-marker assay, taking into account the expression of at least 1 of the 5 tumor markers, the sensitivity of the test rose to 95.6%, with a specificity of 66.3% and a general concordance with the histopathologic status of 75.3%. Finally, when at least 2 of 3 markers (maspin, cytokeratin 19 and mammaglobin 1) were expressed, the concordance with either SLN or axillary lymph node status was highest (88.4% and 84.6%, respectively). The high prevalence of positive reverse transcription-polymerase chain reaction assays in histologically uninvolved SLNs, however, may hamper extensive application of these techniques in the clinical setting.
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PMID:Reverse transcription-polymerase chain reaction assay for multiple mRNA markers in the detection of breast cancer metastases in sentinel lymph nodes. 1149 30

Histological detection of axillary lymph node metastases is still the most valuable prognostic parameter for breast cancer, but about 30% of node-negative patients relapse within five years, suggesting that current methods are inadequate for identifying metastatic disease. More sensitive, PCR-based methods for the detection of metastatic cells are now available, enabling the amplification of cancer cell-specific mRNA messages by the RT-PCR assay. An ideal tumour marker, consistently expressed in tumour samples and not at all in normal lymph nodes, remains to be identified. The present study first investigated the expression of seven mRNA markers, CEA, CK19, c-Met, mammaglobin, MUC-1, beta1-->GalNAc-T and p97, selected on the basis of their previously reported specificity for breast cancer cells. Eighteen lymph nodes were examined from patients without tumours. Only mammaglobin mRNA and CEA mRNA were not expressed in normal nodes. All of the other markers showed a band of expression in 17%-55% of cases, indicating that they are not breast cancer-specific. CEA mRNA and mammaglobin mRNA expression could be detected in 15/20 (75%) and 19/20 (95%) primary breast carcinomas, respectively. The expression of mammaglobin mRNA and CEA mRNA was then compared in axillary lymph nodes from 248 consecutive breast cancer patients, 89 with histologically documented lymph node metastasis and 159 without histological evidence of metastatic disease. Ninety-seven per cent of the patients with histologically involved nodes showed expression of mammaglobin mRNA, whereas CEA mRNA was expressed in 79% of these cases. In the group of patients with histologically negative lymph nodes, 46 (29%) and 32 (20%) were found to be positive for mammaglobin and CEA expression, respectively, indicating the presence of metastases not detected by routine histological examination of one lymph node section. These results show that both mammaglobin RT-PCR and CEA RT-PCR are useful tools for the detection of breast cancer metastases in axillary lymph nodes. The detection sensitivity of the mammaglobin RT-PCR is far superior to that of the CEA RT-PCR, allowing the diagnosis of occult metastases in nearly one-third of cases.
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PMID:mRNA markers of breast cancer nodal metastases: comparison between mammaglobin and carcinoembryonic antigen in 248 patients. 1159 97


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