(1/8912) Immune responses to all ErbB family receptors detectable in serum of cancer patients.
Employing NIH3T3 transfectants with individual human ErbB receptor coding sequences as recombinant antigen sources, we detected by immunoblot analysis specific immunoreactivity against all four ErbB receptors among 13 of 41 sera obtained from patients with different types of epithelial malignancies. Overall, serum positivity was most frequently directed against ErbB2 followed by EGFR, ErbB3 and ErbB4. Specificity patterns comprised tumor patients with unique serum reactivity against ErbB2 or ErbB4. Moreover, approximately half of the positive sera exhibited concomitant reactivity with multiple ErbB receptors including EGFR and ErbB2, EGFR and ErbB4, ErbB2 and ErbB3 or EGFR, ErbB2 and ErbB3. Serum reactivity was confirmed for the respective ErbB receptors expressed by human tumor cells and corroborated on receptor-specific immunoprecipitates. Positive sera contained ErbB-specific antibodies of the IgG isotype. Representative immunohistochemical analysis of tumor tissues suggested overexpression of ErbB receptors for which serum antibodies were detectable in five of six patients. These findings implicate multiple ErbB receptors including ErbB3 and ErbB4 in addition to EGFR and ErbB2 in primary human cancer. Heterogeneity of natural ErbB-specific responses in cancer patients warrants their evaluation in light of immunotherapeutic approaches targeting these receptors. (+info)
(2/8912) Development of a sensitive, specific reverse transcriptase polymerase chain reaction-based assay for epithelial tumour cells in effusions.
We developed a sensitive and specific method for the detection of epithelial cancer cells in effusions with a two-stage molecular-based assay which combined enrichment for cancer cells by immunomagnetic bead selection and reverse transcriptase polymerase chain reaction (RT-PCR) detection of epithelial glycoprotein 2 (EGP-2) RNA. Preliminary experiments indicated that immunobead selection was essential to avoid occasional false-positive RT-PCR results, and this method detected ten breast cancer cells electively added to 10(7) cytologically negative effusion cells. We studied 110 cases of pleural (n = 68) and peritoneal (n = 42) effusions (30 from patients with known carcinoma and 80 from those without known carcinoma), and the results were compared with cytological findings. Of 18 effusions that were cytologically positive or suspicious for malignant cells, 17 (94%) were positive for EGP-2 RNA (the one negative sample was from a patient who recently received combination chemotherapy). Of 92 cytologically negative samples, 11 (12%) were positive for EGP-2, including six patients with a history of previous or current carcinoma. Our method appears to be highly specific and increases the sensitivity of detection of malignant cells; it may be a useful adjunct to routine cytopathological examination. (+info)
(3/8912) Genomic structure and alterations of homeobox gene CDX2 in colorectal carcinomas.
Expression of CDX2, a caudal-related homeobox gene, was found to be decreased in colorectal carcinomas. Heterozygous null mutant mice as to Cdx2 develop multiple intestinal adenomatous polyps. To clarify the role of CDX2 in colorectal carcinogenesis, we determined its genomic structure, and searched for mutations of CDX2 in 49 sporadic colorectal carcinomas and ten hereditary non-polyposis colorectal cancers (HNPCC) without microsatellite instability. None of them exhibited a mutation. We further examined 19 HNPCC carcinomas with microsatellite instability for mutations in a (G)7 repeat site within CDX2. One of them (5.3%) exhibited one G insertion. Loss of heterozygosity was observed in 2 of the 20 (10%) informative sporadic carcinomas, and in one of the three (33.3%) informative HNPCC cancers. These data indicate that CDX2 may play only a minor role in colorectal carcinogenesis. (+info)
(4/8912) Analysis of TSG101 tumour susceptibility gene transcripts in cervical and endometrial cancers.
Carcinoma of the uterine cervix is a common malignancy among women that has been found to show loss of heterozygosity in the chromosome 11p. Recent studies have localized the TSG101 gene in this region, and also demonstrated a high frequency of abnormalities of this gene in human breast cancer. To determine the role of the TSG101 gene in the carcinogenesis of cervical and uterine carcinoma, 19 cases of cervical carcinoma and five cases of endometrial carcinoma, as well as nearby non-cancerous tissue from the same patients, and 16 blood samples from healthy persons as normal control were analysed by Southern blot analysis of genomic DNA, reverse transcription of the TSG101 mRNA followed by PCR amplification and sequencing of the products. We found that abnormal transcripts of the TSG101 gene were common both in cancerous or non-cancerous tissues of the uterus and cervix and in normal peripheral mononuclear cells. There was no genomic deletion or rearrangement in spite of the presence of abnormal transcripts, and no definite relationship between the abnormal transcripts and HPV infection was found. Although the frequency of abnormal transcripts was higher in cancerous than in non-cancerous tissue, normal peripheral mononuclear cells also had abnormal transcripts. Given these findings, the role of the TSG101 gene as a tumour-suppressor gene should be re-evaluated. Because some aberrant transcripts could be found at the first PCR reaction, we suggest that the aberrant transcripts might be the result of imperfect minor splicesome products. (+info)
(5/8912) Intensive weekly chemotherapy is not effective in advanced pancreatic cancer patients: a report from the Italian Group for the Study of Digestive Tract Cancer (GISCAD).
Twenty-two patients, with locally advanced unresectable and/or metastatic pancreatic carcinoma, received weekly administration of cisplatin 40 mg m(-2), 5-fluorouracil 500 mg m(-2), epidoxorubicin 35 mg m(-2), 6S stereoisomer of leucovorin 250 mg m(-2) and glutathione 1.5 mg m(-2), supported by a daily administration of lenograstim at a dose of 5 microg kg(-1). Nineteen patients were men and three were women. Median age was 63 years (range 47-70). At study entry, pain was present in 15 out of 22 patients (68%) with a mean value of Scott-Huskisson scale of 27.6+/-23.8, whereas a weight loss >10% was present in 15 patients. After eight weekly treatments, three partial responses were achieved for a response rate of 13% (95% CI 0-26%), five patients had stable disease and 14 progressed on therapy. Pain was present in 9 out of 22 patients (40%) with a mean value of Scott-Huskisson scale of 12.3+/-18.4. Eight patients (36%) (three partial response and five stable disease) had a positive weight change. Toxicity was mild: WHO grade III or IV toxicity was recorded in terms of anaemia in 7 out of 188 cycles (3.7%), of neutropenia in 9 out of 188 cycles (4.7%) and of thrombocytopenia in 3 out of 188 cycles (1.5%). Median survival of all patients was 6 months. The outcome of this intensive chemotherapy regimen does not support its use in pancreatic cancer. (+info)
(6/8912) Peritoneal cytology in the surgical evaluation of gastric carcinoma.
Many patients undergoing surgery for gastric carcinoma will develop peritoneal metastases. A method to identify those patients at risk of peritoneal recurrence would help in the selection of patients for adjuvant therapy. Peritoneal cytology has received little attention in the West, but may prove a useful additional means of evaluating patients with gastric cancer. The aims of this study were to evaluate sampling techniques for peritoneal cytology in patients with gastric cancer, to assess the prognostic significance of free peritoneal malignant cells and to discover the effect of the operative procedure on dissemination of malignant cells. The study is based on 85 consecutive patients undergoing surgical treatment of gastric cancer and followed up for 2 years or until death. Peritoneal cytology samples were collected at laparoscopy, and at operation prior to resection by intraperitoneal lavage and serosal brushings. After resection, samples were taken by peritoneal lavage, imprint cytology of the resected specimen and post-operatively by peritoneal irrigation via a percutaneous catheter. Malignant cells were diagnosed by two independent microscopists. Preoperative peritoneal lavage yielded malignant cells in 16 out of 85 cases (19%). The yield of free malignant cells was increased by using serosal brushings (by four cases) and imprint cytology (by two cases); all of the cases had evidence of serosal penetration. One serosa-negative case exhibited positive cytology in the post-resection peritoneal specimen in which the preresection cytology specimen was negative. Survival was worse in the cytology-positive group (chi2 = 25.1; P< 0.0001). Among serosa-positive patients, survival was significantly reduced if cytology was positive, if cases yielded by brushings and imprint cytology were included (log-rank test = 8.44; 1 df, P = 0.004). In conclusion, free peritoneal malignant cells can be identified in patients with gastric cancer who have a poor prognosis; the yield can be increased with brushings and imprint cytology in addition to conventional peritoneal lavage. Evaluation of peritoneal cytology by these methods may have a role in the selection of patients with the poorest prognosis who may benefit most from adjuvant therapy. (+info)
(7/8912) Loss of heterozygosity (LOH), malignancy grade and clonality in microdissected prostate cancer.
The aim of the present study was to find out whether increasing malignancy of prostate carcinoma correlates with an overall increase of loss of heterozygosity (LOH), and whether LOH typing of microdissected tumour areas can help to distinguish between multifocal or clonal tumour development. In 47 carcinomas analysed at 25 chromosomal loci, the overall LOH rate was found to be significantly lower in grade 1 areas (2.2%) compared with grade 2 (9.4%) and grade 3 areas (8.3%, P = 0.007). A similar tendency was found for the mean fractional allele loss (FAL, 0.043 for grade 1, 0.2 for grade 2 and 0.23 for grade 3, P = 0.0004). Of 20 tumours (65%) with LOH in several microdissected areas, 13 had identical losses at 1-4 loci within two or three areas, suggesting clonal development of these areas. Markers near RB, DCC, BBC1, TP53 and at D13S325 (13q21-22) showed higher loss rates in grades 2 and 3 (between 25% and 44.4%) compared with grade 1 (0-6.6%). Tumour-suppressor genes (TSGs) near these loci might, thus, be important for tumour progression. TP53 mutations were detected in 27%, but BBC1 mutations in only 7%, of samples with LOH. Evaluation of all 25 loci in every tumour made evident that each prostate cancer has its own pattern of allelic losses. (+info)
(8/8912) Expression of pyrimidine nucleoside phosphorylase mRNA plays an important role in the prognosis of patients with oesophageal cancer.
To clarify the significance of the expression of pyrimidine nucleoside phosphorylase (PyNPase) mRNA as a predictive factor for the prognosis of patients with oesophageal carcinoma, the PyNPase mRNA in the tumours and normal tissues from 55 resected cases of oesophageal carcinoma was examined by a reverse transcription polymerase chain reaction (RT-PCR). As a result, a positive correlation was observed between the tumour/normal (T/N) ratio of the expression of PyNPase mRNA by RT-PCR and that of the enzyme activity of PyNPase based on the findings of an enzyme linked immunosolvent assay (r = 0.594, P = 0.009). The T/N ratio of the expression of PyNPase mRNA was significantly higher in the cases with lymph vessel invasion (P = 0.013), lymph node metastasis (P = 0.0016), and an advanced stage of the disease (P = 0.021) than those without these factors. The patients with a higher T/N ratio of PyNPase mRNA showed significantly worse prognosis than those with a lower T/N ratio (P = 0.023 with log-rank tests). A multivariate analysis for the cumulative survival rates revealed that a high T/N ratio of the expression of PyNPase mRNA was independently related to a poor prognosis. These findings suggested that the determination of PyNPase mRNA by RT-PCR thus appears to be a new useful parameter for identifying both a poor prognosis and a highly malignant potential of oesophageal carcinoma. (+info)