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D Sheer

Publications and source records attributed to D Sheer.

At least 127 records · Page 7Linked to original sources

Establishment and characterisation of three new human ovarian carcinoma cell lines and initial evaluation of their potential in experimental chemotherapy studies.

Three new human cell lines have been established from biopsy specimens of ovarian cystadenocarcinomas: line JA-1 was derived from a primary "solid" tumour from an untreated patient, whilst the other lines were derived from ascites from patients previously treated with chlorambucil plus either cyclophosphamide (TR175) or cisplatin (TR170). Their in vitro characteristics are compared with those of the established SK-OV-3 line of similar origin. Each line has a distinct morphology and expresses a unique isozyme profile and karyotype. All 4 lines have comparable population doubling times of 28-38 hr. Only 3 lines reproducibly form colonies in soft agar, but the JA-1 line, which failed to clone, readily produces xenografts in nude mice. Drug sensitivity testing, using clonogenic or growth-inhibition assays, shows that these lines express a wide range of sensitivities to cisplatin (greater than 20-fold), with the TR175 cells proving particularly sensitive, but a narrower range of sensitivity (less than or equal to 10-fold) to adriamycin. Following 6 24-hr pulsed exposures in vitro to drug concentrations between IC50 and IC90 values, significant resistance develops to adriamycin in each line tested. In contrast, with cisplatin treatment, all lines retain their original sensitivities, except for TR170 cells exposed to the highest concentration, which express cisplatin resistance.

Cell Line↗

The human homologue of the mouse t-complex gene, TCP1, is located on chromosome 6 but is not near the HLA region.

Southern blot analysis indicates that there are four sequences in the human genome related to the mouse t-complex gene Tcp-1. All four genes were cloned and partial sequencing showed that one of them was a functional gene, and the other three were pseudogenes. The human sequences were all approximately 90% related to each other and 82-89% related to the mouse Tcp-1a sequence. Human TCP1 cDNA clones from both fibrosarcoma and B cell lines confirmed that there was a single expressed gene. mRNA transcripts of different sizes were accounted for by two different polyadenylation signals. The human TCP1 gene shared some amino acid substitutions with the mouse t-complex allele (Tcp-1a) which were not found in Tcp-1b. The functional human TCP1 gene was mapped, using a panel of somatic cell hybrids, as well as in situ analysis, to the long arm of chromosome 6 at 6q23-qter and thus is not closely linked to the HLA complex on the short arm. For this reason and others it is unlikely that there is a human equivalent of the mouse t-complex.

Amino Acid Sequence↗

The gene coding for the human T-lymphocyte CD2 antigen is located on chromosome 1p.

A cDNA clone encoding the human T lymphocyte sheep erythrocyte receptor [the CD2 (T11) antigen] was used as a probe to define the chromosomal location of the gene. The signal, revealed by hybridisation to Southern blots of genomic DNA from somatic cell hybrids, showed a high degree of concordance for human chromosome 1. In particular, the hybrid F4Sc13C19 which contained the short arm only of human chromosome 1 was positive. The location of the CD2 gene to 1p13 was confirmed by in situ hybridisation.

Animals↗

Chromosomal locations of the gene coding for the CD3 (T3) gamma subunit of the human and mouse CD3/T-cell antigen receptor complexes.

The gene coding for the Mr 26000 gamma chain of the human CD3 (T3) antigen/T-cell antigen receptor complex was mapped to chromosome band 11q23 by using a cDNA clone (pJ6T3 gamma-2), by in situ hybridization to metaphase chromosomes and by Southern blot analysis of a panel of human-rodent somatic cell hybrids. The mouse homolog, here termed Cdg-3, was mapped to chromosome 9 using the mouse gamma cDNA clone pB10.AT3 gamma-1 and a panel of mouse-hamster somatic cell hybrids. Similar locations for the CD3 delta genes have been described previously. Thus, the corporate results indicate that the CD3 gamma and delta genes have remained together since they duplicated about 200 million years ago.

Animals↗

Monosomy 7 and Ph-positive acute lymphoblastic leukaemia: cytogenetic and molecular aspects.

A combination of monosomy 7 and translocation t(9;22) (q34;q11), rarely observed in acute lymphoblastic leukaemia (ALL), is here reported: a peculiarity of this case was that the "breakpoint cluster region" on chromosome 22 was not rearranged, as demonstrated by molecular analysis, and a new c-abl protein (p190) was found, instead of the usual p210 protein usually associated with the Ph chromosome; moreover a rearrangement of c-abl oncogene was found. The clinical course of this patient was, as expected, unfavorable: a few normal metaphases were observed during a short partial remission.

Adult↗

Cytogenetic analysis of four human ovarian carcinoma cell lines.

Four cell lines derived from adenocarcinomas of the ovary, including three recently established cell lines, have been karyotyped. Chromosomes #1, #3, and #6 were found to be frequently involved in translocations with various other chromosomes, in agreement with results of other investigators, strongly implicating genes on these chromosomes in ovarian tumorigenesis.

Adenocarcinoma↗

The human placental alkaline phosphatase gene and related sequences map to chromosome 2 band q37.

A human placental alkaline phosphatase (PLAP) cDNA was isolated from a lambda gt 10 library of the cell line HEp-2. Southern blots probed with a fragment of the cDNA clone showed that the human genome may contain more than one PLAP-related sequence. The PLAP probe showed person-to-person variation in banding pattern with a number of enzymes. Using a panel of human/rodent somatic cell hybrids the PLAP sequences were mapped to chromosome 2. In situ hybridization confirmed this assignment and localized the gene(s) to chromosome 2 band q37.

Alkaline Phosphatase↗

Localization of the oncogene c-erbA2 to human chromosome 3.

The human c-erbA1 gene has been previously mapped to chromosome 17. We have now mapped c-erbA2 to the short arm of chromosome 3, using a human genomic probe in Southern analysis of DNA from a panel of human/mouse somatic cell hybrids. In situ hybridization using the same probe on metaphase chromosomes has enabled fine chromosome mapping of c-erbA2 to the chromosome region 3p21-pter.

Animals↗

The hypervariable gene locus PUM, which codes for the tumour associated epithelial mucins, is located on chromosome 1, within the region 1q21-24.

A single hypervariable autosomal gene locus, PUM, codes for a family of mucin-type glycoproteins present in human urine, and in several other normal and malignant tissues of epithelial origin. These mucins can be detected after electrophoresis using a series of monoclonal antibodies that show a pronounced tumour specificity on immunohistochemistry. Using a recently cloned cDNA, pMUC10, coding for the core protein of the PUM coded mucins, to probe DNA isolated from a series of human-rodent somatic cell hybrids, we have assigned the PUM locus to chromosome 1. This assignment was confirmed by in situ hybridization of pMUC10 to lymphocyte metaphase chromosomes and the gene was shown to be located within the region 1q21-24.

Animals↗

Characterization and chromosomal assignment of a human cell surface antigen defined by the monoclonal antibody AUAI.

We describe the chromosomal assignment and biochemical characterization of the genetic locus controlled by a human cell surface antigen which is defined by the monoclonal antibody (MAb) AUAI. This gene product is only expressed on epithelial cells. Therefore, human-mouse somatic cell hybrids of epithelial origin were used to assign this gene to chromosome 2. Cell surface iodination of the hybrids and parental cells followed by immunoprecipitation and polyacrylamide gel electrophoresis showed that AUAI detected a single 35-kDa protein. The MAb AUAI reacted on tissue sections with a subset of normal epithelial cells, but in tumours it showed a much wider distribution, though still only on epithelium-derived tumours.

Antibodies, Monoclonal↗

Transformation associated p53 protein is encoded by a gene on human chromosome 17.

The human gene for the transformation-associated p53 phosphoprotein (P53) was assigned to the short arm of chromosome 17 using human-rodent somatic cell hybrids and Southern filter hybridization of cell hybrid DNA. The filters were hybridized to radiolabeled DNA from a genomic clone which contained P53 nucleotide sequences. Hybridization of the probe to a 2.5-kb human DNA fragment in HindIII-digested DNA was used to identify the human P53 gene.

Animals↗

Incidence of the 15q+;17q- chromosome translocation in acute promyelocytic leukaemia (APL).

Cytogenetic analysis was carried out on peripheral blood cultures from seven patients with acute promyelocytic leukaemia (APL-M3). A reciprocal 15;17 chromosome translocation, t(15q+;17q-), was found in all cases, and the breakpoints estimated to be 15q22 and 17q12-21. In addition to the t(15q+;17q-), trisomy 10 was found in 50% of cells analysed in one case. These results suggest that the 15;17 chromosome translocation may be observed in most cases of APL where the leukaemic cells are cultured before cytogenetic analysis is performed. The use of conditioned media in the culture of leukaemic cells is also described.

Adult↗

Monosomy 7 and multipotential stem cell transformation.

Monosomy 7 was the sole karyotypic abnormality seen in a case of biphenotypic leukaemia involving both the myeloid and lymphoid lineages and in a case of de novo ALL undergoing a phenotypic shift to acute myeloid leukaemia at relapse. These observations suggest that monosomy 7 can be associated with transformation of a common lymphoid-myeloid progenitor cell.

Aged↗

Localization of the oncogene c-erbA1 immediately proximal to the acute promyelocytic leukaemia breakpoint on chromosome 17.

Using in situ hybridization, c-erbA1 has been mapped immediately distal to the translocation breakpoint on chromosome 17 in fibroblasts with a karyotype 46,XX, t(15;17)(q22;q11). Previous work has shown that c-erbA1 is proximal to the translocation breakpoint on chromosome 17 in the t(15;17)(q22;q12-21) in acute promyelocytic leukaemia. The oncogene can therefore be localized to the region of chromosome 17 between the breakpoints in 17q11 and 17q12-21.

Chromosome Banding↗

The isolation and characterization of colorectal epithelial cell lines at different stages in malignant transformation from familial polyposis coli patients.

The genetic disease familial polyposis coli (hereditary adenomatosis of the colon and rectum) provides an excellent model for the study of tumour progression in the large bowel. We have isolated and characterized four epithelial cell lines from colorectal tumours from polyposis coli patients. These cell lines are grown on collagen-coated Petri dishes in the presence of mouse 3T3 feeder cells in medium containing 20% foetal bovine serum. Of these cell lines three were isolated from premalignant adenomas and one from an adenocarcinoma. All four lines have a characteristic cuboidal epithelial morphology, and their epithelial origin was confirmed by positive staining with a monoclonal antibody which reacts specifically with the keratin filaments of simple epithelia. The adenoma-derived lines display ultrastructural features characteristic of colonic epithelium including desmosomes, microvilli and mucin droplets. One of the adenoma-derived cell lines, designated PC/AA, has retained differentiated functions in culture, namely mucin production, after 21 in vitro passages. PC/AA has a karyotype of 46, XY with no detectable chromosome rearrangements. The adenoma-derived lines could be passaged from clumps of cells but not from single cells even in the presence of 3T3 feeder cells. The carcinoma-derived line, designated PC/JW, could however grow from single cells in the presence of a feeder layer. The one premalignant adenoma-derived line tested so far, PC/AA, did not produce tumours in athymic nude mice. In contrast, the carcinoma-derived line, PC/JW was tumorigenic in athymic nude mice. PC/JW produced moderately well-differentiated tumours which were histologically similar to the adenocarcinoma from which the cell line was isolated. PC/JW has a near-diploid chromosome number with an isochromosome (1q), an isochromosome (14q) and an (Xp; 17q) translocation. Unidentified marker chromosomes were present in a few cells. The features at present which distinguish the carcinoma-derived line from the adenoma-derived lines are tumorigenicity, growth from single cells and chromosomal abnormalities. The isolation and characterization of differentiating human epithelial cell lines at different stages in malignant transformation provide an opportunity to examine the cellular and molecular mechanisms controlling tumour progression in the large intestine, and to obtain an insight into the multistep process of human epithelial carcinogenesis.

Adenoma↗

Chromosomal localisation of the human homologues to the oncogenes erbA and B.

Avian erythroblastosis virus (AEV) induces acute erythroleukemia and sarcomas in vivo and it transforms erythroblasts and fibroblasts in vitro. The virus has two host cell-derived genes, v-erbA and v-erbB. The latter encodes the oncogenic capacity of the virus, whereas v-erbA enhances the erythroblast transforming effects of v-erbB while being unable to induce neoplasms independently. Recently, human cellular homologues of these viral erb genes have been isolated. The chromosomal locations of two of these genes have been determined using EcoRI-digested DNA prepared from human-mouse somatic cell hybrids. The human c-erbA1 gene has been assigned to chromosome 17 and is located between 17p11 and 17q21. The human c-erbB sequence has been assigned to chromosome 7 and is located between 7pter and 7q22. Thus, in the human genome these genes are on two separate chromosomes. No evidence for the involvement of the human c-erb genes in neoplasia has been found.

Animals↗