Prognostic Role of a Multimarker Analysis of Circulating Tumor Cells in Advanced Gastric and Gastroesophageal Adenocarcinomas.

OBJECTIVE: We aimed to assess the prognostic value of circulating tumor cells (CTC) in patients with advanced gastric and gastroesophageal adenocarcinomas. METHODS: The presence of CTC was evaluated in 62 patients with advanced gastric and gastroesophageal adenocarcinomas before systemic therapy and at follow-up through immunomagnetic enrichment for mucin 1- and epithelial cell adhesion molecule (EpCAM)-positive cells, followed by real-time RT-PCR of the tumor-associated genes KRT19, MUC1, EPCAM, CEACAM5 and BIRC5. RESULTS: The patients were stratified into groups according to CTC detection (CTC negative: with all marker genes negative; CTC positive: with at least 1 of the marker genes positive). Patients who were CTC positive at baseline had a significantly shorter median progression-free survival (PFS; 3.5 months, 95% CI: 2.9-4.2) and overall survival (OS; 5.8 months, 95% CI: 4.5-7.0) than patients lacking CTC (PFS 10.7 months, 95% CI: 6.9-14.4, p<0.001; OS 13.3 months, 95% CI: 8.0-18.6, p=0.003). Alterations in the marker profile during the course of chemotherapy were not predictive of clinical outcome or response to therapy. Yet, a favorable clinical response depended significantly on CTC negativity (p=0.03). CONCLUSION: Our data suggest that the presence of CTC is a major predictor of outcome in patients with gastric and gastroesophageal malignancies.

Prognostic and predictive value of circulating tumor cell analysis in colorectal cancer patients.

OBJECTIVE: The aim of this study was to assess the prognostic and predictive values of circulating tumor cell (CTC) analysis in colorectal cancer patients. PATIENTS AND METHODS: Presence of CTCs was evaluated in 60 colorectal cancer patients before systemic therapy--from which 33 patients were also evaluable for CTC analysis during the first 3 months of treatment--through immunomagnetic enrichment, using the antibodies BM7 and VU1D9 (targeting mucin 1 and EpCAM, respectively), followed by real-time RT-PCR analysis of the tumor-associated genes KRT19, MUC1, EPCAM, CEACAM5 and BIRC5. RESULTS: Patients were stratified into groups according to CTC detection (CTC negative, when all marker genes were negative; and CTC positive when at least one of the marker genes was positive). Patients with CTC positivity at baseline had a significant shorter median progression-free survival (median PFS 181.0 days; 95% CI 146.9-215.1) compared with patients with no CTCs (median PFS 329.0 days; 95% CI 299.6-358.4; Log-rank P < .0001). Moreover, a statistically significant correlation was also founded between CTC detection during treatment and radiographic findings at the 6 month staging. This correlation applied to CTC results before therapy (odds ratio (OR), 6.22), 1 to 4 weeks after beginning of treatment (OR, 5.50), 5 to 8 weeks after beginning of treatment (OR, 7.94) 9 to 12 weeks after beginning of treatment (OR, 14.00) and overall CTC fluctuation during the course of treatment (OR, 20.57). CONCLUSION: The present study provides evidence of a strong correlation between CTC detection and radiographic disease progression in patients receiving chemotherapy for colorectal cancer. Our results suggest that in addition to the current prognostic factors, CTC analysis represent a potential complementary tool for prediction of colorectal cancer patients' outcome. Moreover, the present test allows for molecular characterization of CTCs, which may be of relevance to the creation of personalized therapies.

Multimarker gene analysis of circulating tumor cells in pancreatic cancer patients: a feasibility study.

OBJECTIVE: The aim of this study was to develop an immunomagnetic/real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay and assess its clinical value for the molecular detection of circulating tumor cells (CTCs) in peripheral blood of pancreatic cancer patients. METHODS: The presence of CTCs was evaluated in 34 pancreatic cancer patients before systemic therapy and in 40 healthy controls, through immunomagnetic enrichment, using the antibodies BM7 and VU1D9 [targeting mucin 1 and epithelial cell adhesion molecule (EpCAM), respectively], followed by real-time RT-PCR analysis of the genes KRT19, MUC1, EPCAM, CEACAM5 and BIRC5. RESULTS: The developed assay showed high specificity, as none of the healthy controls were found to be positive for the multimarker gene panel. CTCs were detected in 47.1% of the pancreatic cancer patients before the beginning of systemic treatment. Shorter median progression-free survival (PFS) was observed for patients who had at least one detectable tumor-associated transcript, compared with patients who were CTC negative. Median PFS time was 66.0 days [95% confidence interval (CI) 44.8-87.2] for patients with baseline CTC positivity and 138.0 days (95% CI 124.1-151.9) for CTC-negative patients (p = 0.01, log-rank test). CONCLUSION: Our results suggest that in addition to the current prognostic methods, CTC analysis represents a potential complementary tool for prediction of outcome in pancreatic cancer patients.

Development of a molecular multimarker assay for the analysis of circulating tumor cells in adenocarcinoma patients.

BACKGROUND: The analysis of circulating tumor cells (CTCs) is emerging as a promising diagnostic tool in oncology. However, even if a variety of methods for CTC isolation have been already developed, their specificity and/or sensitivity still remain problematic. The aim of this study was to develop an immunomagnetic/real-time reverse transcription polymerase chain reaction (RT-PCR) assay for the molecular detection of circulating tumor cells (CTCs) in peripheral blood (PB) of adenocarcinoma cancer patients. METHODS: The presence of CTCs was evaluated in 945 PB blood samples from 247 adenocarcinoma cancer patients and in 42 healthy controls by immunomagnetic enrichment using the antibodies BM7 and VU1D9 followed by real-time RT-PCR analysis of the marker genes KRT19, MUC1, EPCAM, CEACAM5, BIRCS, SCGB2A2, and ERBB2. RESULTS: The developed assay showed not only high specificity, as none of the healthy controls were found positive for the multimarker gene panel, but also great sensitivity as CTCs were detected in adenocarcinomas arising from 10 different organs. According to tumor primary origin, CTC positivity was detected in 33.3% of Ampulla of Vater adenocarcinomas, 69.6% of bile ducts adenocarcinomas, 61.3% of breast adenocarcinomas, 61.3% of cardia adenocarcinomas, 60.6% of colon adenocarcinomas, 66.7% of esophagus adenocarcinomas, 57.1% of pancreas adenocarcinomas, 66.7% of rectum adenocarcinomas, 33.3% of small intestine adenocarcinomas, and 62.2% of stomach adenocarcinomas. CONCLUSIONS: Our results suggest that the current developed technique can be used to detect CTCs in all major adenocarcinomas, with great sensitivity without compromising specificity.

Cell growth stimulation by CRASH, an asparaginase-like protein overexpressed in human tumors and metastatic breast cancers.

The gene encoding CRASH, a human asparaginase-like protein, has been cloned and its transcriptional activation has been detected in gynecologic cancers. To define the expression of CRASH in human tumors and its possible functional role, monoclonal antibodies against the CRASH protein have been generated. In non-transformed tissues CRASH was only detected in testis, brain, esophagus, prostate and proliferating endometrium. On the other hand, 36/50 ovarian carcinomas, 16/78 mammary carcinomas, 6/6 uroepithelial bladder carcinomas and 5/33 colon carcinomas scored positive for CRASH, with the absence of reactivity in the corresponding normal tissues. Strikingly, 11 out of the 16 breast cancers that expressed CRASH were metastatic, nominating CRASH to be functionally relevant in tumor progression. Twenty-eight out of 42 endometrium tumors expressed CRASH at high levels as did 5/41 prostate carcinomas, as well as ovary and breast cancers, indicating a regulation of CRASH expression by sex hormones. A bona fide estrogen responsive element was detected at bases -201/-183. This proved to be highly preserved across species, supporting an actual functional role. Asparaginase-like proteins play a role in growth regulation and signaling by p70 S6 kinase. The somatic knock-out of CRASH resulted in significant inhibition of growth of KM12L4A colon carcinoma cells, which abundantly express CRASH, whereas the proliferation of the syngeneic, weakly-expressing, slowly-growing KL12SM was not affected. These results are consistent with a selective growth advantage for aggressive cancers expressing CRASH, and nominate CRASH as a novel diagnostic and therapeutic tumor target.

Heterogeneous expression of tumor-associated genes in disseminated breast cancer cells.

BACKGROUND: Gene expression profiles were determined to demonstrate heterogeneity of viable disseminated tumor cells (DTC) in the blood of breast cancer patients. PATIENTS AND METHODS: All patients (n = 48) suffered from metastatic disease (M1) and were treated with chemotherapy and/or Herceptin, respectively. Blood samples were analyzed by a DTC detection assay consisting of immunomagnetic tumor cell selection combined with expression profiling of the tumor-associated transcripts GA733-2, MUC-1, HER-2 and Claudin-7. In addition, the correlation of HER-2 expression in DTC with histopathologically determined HER-2 status in distant metastases and primary tumors in selected cases was investigated. RESULTS: DTC were detected in 69% (p < 0.0001) of breast cancer patients. The expression profiles were shown to be heterogeneous within different patients and even within the follow-up period of patients, reflecting the expected heterogeneity of DTC. Furthermore, preliminary results showed a correlation between HER-2 gene expression in DTC and HER-2 overexpression in tumor tissue of distant metastases. CONCLUSION: The results suggest a clinical value of the DTC detection assay with respect to a more precise characterization of individual cancer disease and selection for therapy. More emphasis should be placed on HER-2 expression in DTC as a possible precursor of distant metastases.

Identification of L1CAM, Jagged2 and Neuromedin U as ovarian cancer-associated antigens.

In order to identify tumor-associated genes of ovarian carcinoma, we have investigated the transcriptional profile of 11 ovarian tumor cell lines and 2 immortalized ovarian surface epithelial cell lines (IOSE) derived from normal ovarian epithelium with Affymetrix GeneChip technology. We have analyzed the expression profile of 12652 genes. A total of 136 genes were up-regulated and 165 were down-regulated in at least 7 out of 11 ovarian tumor cell lines in comparison to the transcriptional profile of the IOSE cell lines with a change factor of +/-2 as the threshold level. We have focused on up-regulated genes encoding for transmembrane receptors and secreted proteins as possible markers for diagnosis and targets for therapy of ovarian carcinoma. We have identified the transmembrane Notch ligand Jagged2, cell adhesion molecule L1CAM and the secreted polypeptide Neuromedin U as possible candidates. Immunohistochemical analysis revealed expression of L1CAM predominantly in ovarian carcinomas, in borderline tumors to a lesser extent, and very rarely in ovarian non-epithelial types of cancer. Further analysis of L1CAM revealed that a splice variant lacking exons 2 and 27 is predominantly expressed in ovarian carcinoma cell lines DW and GG. Functional investigation of stable Delta(2,27)L1CAM transfectants of the ovarian tumor cell line OV-MZ-2 revealed significantly stronger adhesion to laminin in comparison to mock transfectants.

Identification of CRASH, a gene deregulated in gynecological tumors.

We have identified CRASH, a human asparaginase-like protein which is composed of 308 amino acids and exhibits 32% homology to human aspartylglucosaminadase at the amino acid level. Database analysis revealed that the gene corresponding to CRASH is composed of 7 exons and 6 introns. Steady-state level of CRASH mRNA was found to be increased in 5 cell lines derived from metastatic lesions compared with 2 cell lines derived from primary mammary carcinoma and HMEC (human mammary epithelial cells). We found that the mRNA level of CRASH correlates with the metastatic propensity of several isogenic human colon cancer and pancreatic carcinoma cell lines. CRASH corresponds to a recently identified sperm autoantigen and furthermore we have demonstrated inducibility of CRASH mRNA by androgen and progesterone. Investigation of several types of human cancers and their corresponding normal tissues revealed high levels of CRASH mRNA in uterine, mammary and ovarian tumors compared with the corresponding normal tissues. CRASH mRNA expression was analysed in breast cancer samples with disclosed clinico-pathological features and corresponding normal tissues. The levels of CRASH mRNA were significantly up-regulated in tumors compared with normal breast tissues and correlate with lack of estrogen receptor expression of the tumors.

Serum levels of soluble E-selectin are associated with the clinical course of metastatic disease in patients with liver metastases from breast cancer.

Increasing evidence indicates that the expression of the endothelial adhesion molecule E-selectin is associated with progression and metastasis of breast cancer. Patients with liver metastases also show increased serum levels of the soluble form of E-selectin. It was our aim to compare serum levels of soluble E-selectin (sES) in such patients with the biology of the primary tumor and the course of the metastatic disease under therapy. We examined 69 patients with liver metastases from breast cancer who were selected to receive systemic tumor therapy because of progressive disease (n = 44) or newly detected liver metastases (n = 25). Serum concentrations of sES were measured before each therapy cycle using a specific ELISA. Serum concentrations of sES before the start of therapy were compared to clinical parameters and histopathological findings referring to the primary tumor. Secondly, serum levels of sES were compared to serum concentrations of the corresponding tumor markers. We observed a possible trend for certain unfavorable prognostic parameters (e.g., young women, low-graded tumors, human epidermal growth factor receptor 2 overexpression) to be related to higher serum levels of sES. Serum levels of sES were correlated with tumor marker levels in a logarithmical relation (r = 0.44, P < 0.0005). In some cases it could be demonstrated that serum levels of sES changed similarly to the course of tumor marker levels. We conclude that serum levels of sES are associated with the clinical course of liver metastases from breast cancer. Further investigations are needed to clarify if serum levels of sES may serve as tumor marker in certain clinical situations. E-selectin should be evaluated as a possible target for antimetastatic therapy studies.

Expression of MUC 1 and Ep-CAM in Merkel cell carcinomas: implications for immunotherapy.

The Merkel cell carcinoma (MCC) is a highly malignant carcinoma of the skin that is characterized by granules containing neuroendocrine peptides and by the expression of simple epithelial type cytokeratins. The glycoprotein Ep-CAM is a homophilic cell-cell adhesion molecule, present in most simple, pseudostratified and transitional epithelia and the tumors derived therefrom. MUC 1 is a well-established marker for squamous cell carcinomas and is generally secreted by glandular epithelial cells. We compared the expression of Ep-CAM and MUC 1 in Merkel cells and 33 cases of MCC and 12 MCC metastases using immunohistochemistry on paraffin-embedded sections. In addition, we examined the glycosylation status of MUC 1 with specific monoclonal antibodies. MUC 1 and Ep-CAM were expressed in Merkel cells and in about 82% and 70% of all MCC irrespective of clinical outcome. Both antigens were expressed in 66% of metastases. Similar to breast cancer, the presence of MUC 1 was not correlated with clinical outcome, but the staining intensity of monoclonal antibodies against glycosylation-independent and hypoglycosylated epitopes was. In MCC we found an altered glycosylation pattern in the immunodominant APDTR region of MUC 1 as compared to normal Merkel cells. Hyperglycosylated MUC 1 epitopes were not present in either MCC or normal Merkel cells. There was no correlation between glycosylation pattern and clinical outcome. Ep-CAM expression seemed to be stronger in primary MCC that metastasized than in those that did not. In conclusion, Merkel cells and the majority of MCC express Ep-CAM and MUC 1. This opens the door for treatments based on monoclonal antibodies or vaccination strategies against these antigens, already established for other tumor entities.

Immunocytochemical detection of HPV high-risk type L1 capsid proteins in LSIL and HSIL as compared with detection of HPV L1 DNA.

OBJECTIVE: To investigate the prevalence of HPV L1 capsid proteins in HPV-infected HSIL and LSIL. STUDY DESIGN: Cervical smears from 74 women with cytologically and histologically confirmed LSIL (n = 32) and HSIL (n = 42) were collected prospectively to detect HPV high-risk (hr) types 16, 18, 33, 35, 39, 45, 56 and 58 L1-DNA by standardized L1-consensus primer PCR (MY 09/11) and L1 capsid proteins by immunocytochemistry using monoclonal antibodies T31 (HPV16) and T16 (HPV hr) in a standardized protocol. RESULTS: In HSIL and LSIL, L1 DNA was found for HPV hr in 93% and 59% and for HPV16 in 69% and 37% of the specimens, respectively. HPV L1 capsid proteins were detected in HSIL and LSIL for HPV hr in 33% and 44% and for HPV16 in 29% and 31% of the specimens, respectively. Expression of L1 capsid proteins was significantly reduced, by 59.6% for HPV hr L1 DNA-positive HSIL (P < .01) and by 40.4% for HPV 16 L1 DNA-positive HSIL (P < .01). In HPV 16 DNA-positive and HPV hr DNA-positive LSIL, no significant reduction of corresponding L1 capsid protein expression could be demonstrated. CONCLUSION: These data suggest a disturbed viral cellular interaction in HPV 16 and HPV hr-infected HSIL, with loss of viral L1 capsid antigen. In this context there is a possible role of T31 and T16 as prognostic markers to predict the prognosis of CIN.

Multimarker Analysis of Circulating Tumor Cells in Peripheral Blood of Metastatic Breast Cancer Patients: A Step Forward in Personalized Medicine.

AIM: To develop an immunomagnetic assay for the isolation of circulating tumor cells (CTCs) followed by the analysis of a multimarker panel, which will enable the characterization of these malignant cells with high accuracy. PATIENTS AND METHODS: Peripheral blood (PB) was collected from 32 metastatic breast cancer patients and 42 negative controls. The antibodies BM7 and VU1D9 were used for immunomagnetic tumor cell enrichment. A real-time reverse transcription-polymerase chain reaction (RT-PCR) approach for the markers KRT19, SCGB2A2, MUC1, EPCAM, BIRC5 and ERBB2 was used for CTC detection and characterization. RESULTS: THE POSITIVITY RATES FOR EACH MARKER WERE AS FOLLOWS: 46.9% for KRT19, 25.0% for SCGB2A2, 28.1% for MUC1, 28.1% for EPCAM, 21.9% for BIRC5, and 15.6% for ERBB2. After the creation of individualized cutoffs, the sensitivity and specificity of the combined marker gene panel increased to 56.3% and 100%, respectively. Interestingly, 27.0% of the HER2-negative tumor patients showed ERBB2 mRNA-positive CTCs. CONCLUSIONS: The described technique can be used to measure CTCs with great accuracy. The use of a multimarker panel for the characterization of CTCs may provide real-time information and be of great value in therapy monitoring.

Serum levels of hepatocyte growth factor/scatter factor in patients with liver metastases from breast cancer.

OBJECTIVE: Recent studies have shown that the pleiotropic cytokine hepatocyte growth factor/scatter factor (HGF/SF) and its receptor c-Met play major roles in the malignant progression of numerous tumors. For patients with breast cancer liver metastases, increased serum levels of HGF/SF have been reported. We studied the relationship between the clinical course of the disease and the serum levels of HGF/SF in such patients. METHODS: We examined 51 patients treated for breast cancer liver metastases. Serum concentrations of HGF/SF were measured before each therapy cycle and compared to the corresponding tumor marker levels. RESULTS: Mean serum levels of HGF/SF in patients with liver metastases were increased above the reported reference levels of primary breast cancer patients. Serum levels of HGF/SF were correlated with tumor marker levels in a logarithmic relation (r = 0.47, p < 0.001). In some cases serum concentrations of HGF/SF changed similarly to the course of the corresponding tumor markers. CONCLUSIONS: Serum levels of HGF/SF are associated with the clinical course of metastatic breast cancer patients with liver metastases. Further studies are required to clarify the potential value of the HGF/SF serum concentration as a tumor marker. HGF/SF and its receptor c-Met should be further evaluated as therapeutic targets.