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Biomedical subjects

Michèle Cottier

Publications and source records attributed to Michèle Cottier.

7 recordsLinked to original sources

The use of MN/CA9 gene expression in identifying malignant solid renal tumors.

OBJECTIVE: Small solid renal tumors are increasingly encountered. It is important to determine the malignancy of solid renal tumors for the choice of treatment. MN/CA9 is expressed in malignant renal cells but absent in normal cells. MN/CA9 is one of the most powerful gene markers available for RCC. The objective of this pilot study is to utilize MN/CA9 gene expression in FNA biopsy to determine the malignancy of imaging-indeterminate solid renal tumors. METHODS: A total of 35 patients with an imaging-indeterminate solid renal mass entered into this study. The molecular protocol consisted of a rapid column extraction of RNA and one-step RT-PCR for the detection of MN/CA9 gene expression. The preoperative molecular diagnosis was compared with postoperative pathology. RESULTS: There were 28 RCCs (19 clear cell carcinomas, 7 papillary carcinomas and 2 chromophobe carcinomas) and 7 benign tumors proved by postoperative pathology. The overall sensitivity and specificity for MN/CA9 were respectively 68% and 100%. MN/CA9 was positive in 16/19 (84%) FNA biopsies of clear cell RCCs. No false positive appeared for MN/CA9 gene expression. Moreover, MN/CA9 gene expression was positive in 8/13 (62%) of false negative or suspect cytology. CONCLUSION: Detection of MN/CA9 gene expression in FNA biopsy is possible. Its detection can be helpful in identifying the malignancy among renal tumors.

Adenocarcinoma, Clear Cell↗

Conventional liquid-based techniques versus Cytyc Thinprep processing of urinary samples: a qualitative approach.

BACKGROUND: The aim of our study was to objectively compare Cytyc Thinprep and other methods of obtaining thin layer cytologic preparations (cytocentrifugation, direct smearing and Millipore filtration) in urine cytopathology. METHODS: Thinprep slides were compared to direct smears in 79 cases. Cytocentrifugation carried out with the Thermo Shandon Cytospin 4 was compared to Thinprep in 106 cases, and comparison with Millipore filtration followed by blotting was obtained in 22 cases. Quality was assessed by scoring cellularity, fixation, red blood cells, leukocytes and nuclear abnormalities. RESULTS: The data show that 1) smearing allows good overall results to be obtained, 2) Cytocentrifugation with reusable TPX chambers should be avoided, 3) Cytocentrifugation using disposable chambers (Cytofunnels or Megafunnel chambers) gives excellent results equalling or surpassing Thinprep and 4) Millipore filtration should be avoided, owing to its poor global quality. Despite differences in quality, the techniques studied have no impact on the diagnostic accuracy as evaluated by the rate of abnormalities. CONCLUSION: We conclude that conventional methods such as cytocentrifugation remain the most appropriate ones for current treatment of urinary samples. Cytyc Thinprep processing, owing to its cost, could be used essentially for cytology-based molecular studies.

Journal Article↗

Evaluation of a panel of molecular markers for the diagnosis of malignant serous effusions.

PURPOSE: Our main goal was to evaluate a panel of molecular markers for the detection of cancer cells in serous effusions and to determine their value as an adjunctive reverse transcription-PCR (RT-PCR) test to cytologic examination. EXPERIMENTAL DESIGN: One hundred fourteen serous effusions from 71 patients with tumors and 43 patients with benign diseases were subjected to RT-PCR for expression of carcinoembryonic antigen (CEA), epithelial cell adhesion molecule (Ep-CAM), E-cadherin, mammaglobin, mucin 1 (MUC1) isoforms MUC1/REP, MUC1/Y, and MUC1/Z, calretinin, and Wilms' tumor 1 susceptibility gene. RESULTS: CEA, Ep-CAM, E-cadherin, and mammaglobin were specifically expressed in malignant effusions. The sensitivity of RT-PCR in cytologically negative malignant effusions was 63.1% combining CEA and Ep-CAM (with 100% specificity) and reached 78.9% adding MUC1/Y or MUC1/Z (with 93% specificity). In the whole population of effusions, the combination of cytology with RT-PCR of CEA and Ep-CAM yielded a 90.1% sensitivity, a specificity and a positive predictive value of 100%, and a 86% negative predictive value for malignancy. Adding MUC1/Y or MUC1/Z to the panel, the sensitivity was 94.5% with 93% specificity, 95.7% PPV, and 90.9% negative predictive value. Moreover, CEA and mammaglobin were specifically expressed in epithelial malignancies, and mammaglobin was mainly expressed in effusions from breast carcinoma (97.3% of specificity). CONCLUSIONS: A combination of cytology and RT-PCR analysis of CEA and Ep-CAM significantly improved the detection sensitivity of tumor cells in serous effusions. RT-PCR analysis of CEA, Ep-CAM, and mammaglobin in serous effusions could be a beneficial adjunct to cytology for the diagnosis of malignancy.

Aged↗

Different DNA ploidy patterns for the differentiation of common subtypes of renal tumors.

OBJECTIVES: The common subtypes of renal tumors are conventional or clear cell carcinoma, papillary carcinoma, chromophobe carcinoma and oncocytoma. Each subtype has its distinct histogenesis and clinical evolution. DNA ploidy is viewed as a marker of gross genomic aberrations. The aim of this study is to evaluate the DNA ploidy in the common subtypes of renal tumors to increase our understanding of renal tumor biology and to broaden clinical application of DNA ploidy. METHODS: 38 renal tumor samples (13 clear cell RCCs, 12 papillary RCCs, 7 chromophobe RCCs, and 6 oncocytomas) were studied. Five biopsies of different parts of each fresh tumor were subjected to a flow cytometric analysis of DNA ploidy. RESULTS: All tumors except one papillary RCC generated interpretable DNA histograms. Flow cytometric analysis of oncocytomas showed the diploid pattern (29/30 frequencies) while the chromophobe RCC never showed the diploid pattern (0/55 frequencies) (p<0.01). 3/7 chromopbobe RCCs possessed the hypodiploid stemline. The hypodiploid stemline appeared neither in conventional RCCs (0/63 frequencies) nor in papillary RCCs (0/50 frequencies). The diploid pattern was dominant in conventional and papillary RCCs. 10/13 (76.9%) of clear cell RCCs and 9/11 (81.8%) of papillary RCCs possessed a homogeneous DNA ploidy pattern while only 1/7 (14.3%) has a homogeneous DNA ploidy pattern. 6/7 chromophobe RCCs had multiple aneuploid stemlines. CONCLUSIONS: Flow cytometric analysis reveals that conventional and papillary RCCs are more homogeneous than chromophobe RCC. Each subtype of renal tumors possesses a specific DNA ploidy pattern. The analysis of DNA ploidy is useful for the differentiation of common subtypes of renal tumors in morphologically difficult cases.

Adenocarcinoma, Clear Cell↗

Cytogenetic characterization of seven human cancer cell lines by combining G- and R-banding, M-FISH, CGH and chromosome- and locus-specific FISH.

Leukemia cell lines K562, KG1a, U937, HL60, Jurkat and solid tumor cell lines A549 and M4Beu are widely used in studies of cell cycle, apoptosis and adhesion mechanisms in cancer cells. Although the K562 and U937 cell lines were previously subjected to a detailed cytogenetic characterization, only a few molecular cytogenetic investigations have been performed on the other five cell lines. We combined several molecular cytogenetic techniques, such as fluorescence in situ hybridization (FISH), multicolor FISH (M-FISH), and comparative genomic hybridization (CGH) to demonstrate the precise genetic aberrations in tumor genomes of these seven cell lines. This information may be useful for multiple studies on these cell lines, providing a genetic basis for the interpretations of experimental findings.

Cell Line, Tumor↗

Rapid and sensitive detection of messenger RNA expression for molecular differential diagnosis of renal cell carcinoma.

PURPOSE: The aim of this study was to develop a practical technique to detect mRNA expression and to validate a panel of mRNA markers for molecular differential diagnosis of renal cell carcinoma (RCC). EXPERIMENTAL DESIGN: The renal cancer cell line SKRC-52 was used to set up the technique, which consisted of column extraction of RNA and one-step reverse transcription-PCR. We validated a panel of gene markers, including MN/CA9, cadherin-6, vimentin, mucin1, and parvalbumin, and studied 50 renal tumors (30 conventional, 9 papillary, and 5 chromophobe RCCs and 6 oncocytomas), 10 normal tissues, and 10 normal blood samples. We mimicked fine needle aspiration (FNA) biopsy in 10 kidneys with conventional RCC and applied this technique to 10 preoperative FNA samples from imaging-indeterminate renal tumors. RESULTS: The technique could detect as few as 10 SKRC-52 cells with MN/CA9 as mRNA marker and was less time consuming and labor intensive. MN/CA9 was a sensitive and rather specific gene marker for conventional RCC. Cadherin-6 gene expression was a sensitive marker for conventional and papillary RCC. Vimentin was highly specific for conventional RCC. Mucin1 mRNA was sensitive for papillary and chromophobe RCC and oncocytoma. Parvalbumin mRNA was a sensitive and highly specific marker for both chromophobe RCC and oncocytoma. Thus, these mRNA markers represent the biomarker genes for the subtypes of renal tumors. Finally, we successfully applied the technique to FNA specimens. Five preoperative FNA samples were MN/CA9 gene positive, suggesting a RCC, whereas the routine cytology was positive in only three cases. CONCLUSIONS: A rapid and sensitive assay of mRNA markers was developed for molecular differential diagnosis of RCC. This molecular assay can be used as a powerful ancillary to surgical pathological diagnosis and cytological diagnosis of RCC.

Adenoma, Oxyphilic↗

Macrophages from cancer patients: analysis of TRAIL, TRAIL receptors, and colon tumor cell apoptosis.

BACKGROUND: Tumor-infiltrating macrophages secrete cytokines, including Fas ligand, tumor necrosis factor-alpha (TNF-alpha), and TNF-related apoptosis-inducing ligand (TRAIL). TRAIL induces apoptosis in tumor cells but not in normal cells; however, regulation of TRAIL and its receptors in cancer patients is relatively uncharacterized. We investigated whether macrophages from cancer patients produce TRAIL and whether apoptosis in cultured colon adenocarcinoma cells involves TRAIL and its receptors. METHODS: Macrophages isolated from pleural effusions of nine cancer patients and five control patients with congestive heart failure (whose effusions contained no tumor cells) were cultured. Levels of TRAIL, TNF-alpha, interferon alpha, and Fas ligand in conditioned medium were measured by enzyme-linked immunosorbent assays. Apoptosis of human colon adenocarcinoma cell lines, including Colo 205, was determined by the Annexin V method and terminal deoxynucleotidyltransferase-mediated deoxyuridine 5'-triphosphate nick-end labeling (TUNEL). Cell-surface TRAIL receptors were measured by flow cytometry. RESULTS: Conditioned culture medium from macrophages isolated from pleural effusions containing 1%-5% tumor cells (CM-A) contained TRAIL at 980-1300 pg/mL, whereas that from macrophages from pleural effusions containing more than 50% tumor cells or containing no tumor cells (CM-B) contained TRAIL at 0-50 pg/mL. When cultured with medium containing 50% CM-A, 40% (95% confidence interval [CI] = 30% to 50%) of Colo 205 cells underwent apoptosis; when cultured with 50% CM-B, 8% (95% CI = 3% to 13%) underwent apoptosis. When Colo 205 cells were cultured with 50% CM-A, cell-surface expression of TRAIL death receptors DR5 and DR4 increased 13-fold and sixfold, respectively, compared with that of untreated Colo 205 cells. Recombinant TRAIL induced 90% (95% CI = 85% to 95%) of Colo 205 cells to undergo apoptosis and acted synergistically with TNF-alpha to induce apoptosis. CONCLUSION: Macrophages from cancer patients appear to be activated by tumor cells to produce TRAIL and to increase the expression of TRAIL death receptors DR4 and DR5 on tumor cells.

Adenocarcinoma↗