Biomedical subjects

D Kodagoda

Publications and source records attributed to D Kodagoda.

3 recordsLinked to original sources

PubMed1999

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.

Ascitic Fluid↗

PubMed1998

Characterization of paired tumor and non-tumor cell lines established from patients with breast cancer.

The goal of our study was to develop a panel of tumor cell lines along with paired non-malignant cell lines or strains collected from breast cancers, predominantly primary tumors. From a total of 189 breast tumor samples consisting of 177 primary tumors and 12 metastatic tissues, we established 21 human breast tumor cell lines that included 18 cell lines derived from primary tumors and 3 derived from metastatic lesions. Cell lines included those from patients with germline BRCA1 and FHIT gene mutations and others with possible genetic predisposition. For 19 tumor cell lines, we also established one or more corresponding non-malignant cell strains or B lymphoblastoid (BL) lines, which included 16 BL lines and 7 breast epithelial (2) or stromal (5) cell strains. The present report describes clinical, pathological and molecular information regarding the normal and tumor tissue sources along with relevant personal information and familial medical history. Analysis of the breast tumor cell lines indicated that most of the cell lines had the following features: they were derived from large tumors with or without axillary node metastases; were aneuploid and exhibited a moderate to poorly differentiated phenotype; were estrogen receptor (ER)- and progesterone receptor (PR)-negative; and overexpressed p53 and HER2/neu proteins. Of 13 patients with primary breast cancers receiving curative intent mastectomies, 7 were dead after a mean period of 10 months. Our panel of paired tumor and non-malignant cell lines should provide important new reagents for breast cancer research.

Adult↗

PubMed1998

Allelotyping demonstrates common and distinct patterns of chromosomal loss in human lung cancer types.

Allelic loss is a hallmark of tumor suppressor gene (TSG) inactivation. We have allelotyped 29 paired lymphoblastoid and lung cancer cell lines derived from 11 patients with small cell (SCLC) and 18 patients with non-small cell lung carcinomas (NSCLC). Statistical analysis indicated that a threshold of 30% separated non-random allelic loss from the random genetic deletions of malignancy. We have identified non-random allelic loss at 42 of 54 (78%) specific chromosomal regions examined, with 22 regions (52%) common between the two major lung cancer histologic types. There were 3 regions (7%) with allelic loss specific for SCLC and 17 regions (41%) specific for NSCLC. Furthermore, there were significant differences in loss of heterozygosity (LOH) frequencies between NSCLC and SCLC at 13 regions on eight chromosome arms (3p, 5q, 6q, 9p, 10q, 11p, 13q, and 19p). Eight homozygous deletions were present in seven cell lines at four regions, 3p12, 3p14.2, 9p21, and 10q23-25. We have also identified novel sites of chromosomal deletions. In particular, there was frequent loss at 11p13 in SCLC and loss at 6p21.3 and 13q12.3 in NSCLC. In this study, we demonstrate that a) non-random allelic losses in lung cancer involve multiple regions; b) some losses are common to both NSCLC and SCLC subtypes, whereas others are subtype specific; c) there are genetic deletions at novel chromosomal regions; and d) several homozygous deletions have been noted. Our studies demonstrate the usefulness of continuous cell lines for detailed allelotyping, for comparing genetic abnormalities between SCLC and NSCLC, and for identifying homozygous deletions.

Adult↗