Biomedical subjects

M Debiec-Rychter

Publications and source records attributed to M Debiec-Rychter.

At least 73 records · Page 4Linked to original sources

PubMed1994

Aberrations of chromosome 22 and polysomy of chromosome 8 as non-random changes in clear cell sarcoma.

Cytogenetic analysis was performed on a primary tumor and a metastatic lesion of a clear cell sarcoma of tendons and aponeuroses (CCS), a rare soft tissue neoplasm of uncertain histopathologic origin. Clonal chromosomal abnormalities resulting in two related clones were found in both tumors. The karyotype was near-triploid with several structural and numerical changes, comprising a der(15;22) (q10;q10). Including the present case, 14 of 15 cases of CCS have had structural or numerical aberrations of chromosome 22 and nine of them (65%) displayed a similar or identical t(12;22)(q13-14;q12-13). Our findings suggest that in the absence of specific t(12;22), other abnormalities of chromosome 22 may be significant. In addition, increased doses of chromosome 8 found in 70% of the tumors strongly suggest a significant role for this chromosome in the development of clear cell sarcoma.

Adult↗

PubMed1994

Molecular changes involved in the carcinogenesis of brain tumors.

Current basic research on tumorigenesis suggests that the accumulation of multiple genetic defects underlies the progression of initiated cells toward malignancy. Molecular abnormalities associated with primary brain tumors include a wide variety of changes in tumor-suppressor genes, proto-oncogenes and growth factors. A well-known tumor-suppressor gene, p53 gene, is located on the short arm (p) of chromosome 17 and consists of 11 exons transcribed into a 2.2-2.5 kb messenger (m) RNA that encode for a 53 kDa protein. Its alterations are associated with carcinogenesis of astrocytic tumors. Recent evidence suggests also that the p53 protein may function through promoting the expression of the recently discovered gene, WAF1/Cipl. Loss of chromosome 10 was frequently observed in glioblastoma. Southern blot analysis of glioblastomas revealed that 72% have the chromosome 10 loss and that 38% had amplification of the epidermal growth factor receptor (EGFR) gene. Autocrine stimulation of cell growth requires the presence of both growth factors and their receptors. Other genetic alterations in gliomas include elevated expression of the c-myc, Ha-ras, and c-fos oncogenes with a trend to increase in higher malignant grades.

Base Sequence↗

PubMed1994

Expression of N-myc, c-myc and c-erbB-1 proto-oncogenes in cerebral primitive neuroectodermal tumors (PNET).

Neuroectodermal tumors demonstrate a relatively high incidence of proto-oncogenes amplification. This study attempted to determine the frequency of overexpression of three genes: N-myc, c-myc and c-erbB-1, in human PNET. Immunohistochemical studies revealed 5 to 74% neoplastic cells with positive immunoreactivity to anti-c-myc antibody in all investigated samples. In 3 cases the reactivity was particularly strong and present in more than 50% of tumor cells. Northern blot analysis revealed normal (2.3-kb in size) but significantly higher level of c-myc transcripts in these cases. By using anti-EGFR antibody 3 tumors disclosed 10 to 65% neoplastic cells with positive immunoreactivity. There was no rearrangement detected of their c-erbB-1 or N-myc genes by means of applied methods. Our results suggest that overexpression of c-myc gene is present in 10% of PNET but it is not the consequence of gene amplification. Amplification of N-myc and c-erbB-1 are rare events during PNET development.

Brain Neoplasms↗

PubMed1993

Identity of tumorigenic human urothelial cell lines and 'spontaneously' transformed sublines.

Restriction fragment length polymorphism (RFLP) analysis, comparative marker chromosome analysis, and polymorphic enzyme analysis was carried out on a total of eight human urothelial cell lines and sublines selected according to our knowledge of their HLA-A,B phenotype. RFLP analysis and cytogenetic analysis showed that the cell lines Hu1703He, Hu1922, and T24 are genuine cell lines of different origin. The identity of Hu1703He could not be confirmed by its isozyme phenotype which was identical to the T24 phenotype. RFLP analysis and isozyme analysis revealed that three cell lines, Hu456, Hu549, and Hu961a, and two transformed sublines, HCV-29Tmv and Hu609Tmv, are sublines of T24. A common origin of Hu456, Hu549, Hu961a, HCV-29Tmv, and Hu609Tmv was confirmed by marker chromosome analysis. However, the T24 origin of these cytogenetically related cell lines was not supported by chromosome analysis of T24. RFLP analysis and HLA phenotyping of two tumorigenic and invasive sublines isolated from a culture of non-tumorigenic Hu609 cells showed that non-tumorigenic Hu609 cells can transform 'spontaneously' in vitro into tumorigenic Hu609T cells. The results emphasise the need for careful monitoring and screening of cell lines for their identity using more than one identification parameter.

Cell Line↗

PubMed1992

Cytogenetic analysis of renal angiomyolipoma.

Chromosome analysis of a benign, unilateral, renal angiomyolipoma revealed the karyotype 44,XX,-8, -12, -14, -21, +der (8q14q), + der(12)(12pter----12q14-15::12q24----12q14-15::+ ++21q21----21qter). This indicates that structural changes of 12q13-15, which are so frequently observed in the common malignant and benign lipogenic tumors, may also occur in the rarer variants of these neoplasms.

Aneuploidy↗

PubMed1992

Chemical carcinogenesis of the urinary bladder--a status report.

Cigarette smoking and certain types of occupational exposure to arylamines appear to be the main cause of human urinary bladder cancer. Little is known of the promotion of bladder cancer in humans, although this stage has been demonstrated in rodents. Perhaps as a consequence of initiation, multifactorial alterations of cellular genes occur. These genes include the epidermal growth factor receptor gene, erbB-2, int-2, hst, and H-ras, which exert positive control over cell growth, as well as the suppressor genes Rb-1, and the gene coding for p53. Chromosomal changes such as deletions, translocations and/or amplifications related to these genes may be of significance for prognosis of this disease.

Animals↗

PubMed1992

Two familial 9;17 translocations with variable effect on male carriers fertility.

Two similar, but not identical, familial reciprocal translocations are described. In the first family, four sterile males inherited reciprocal translocation t(9;17)(q11'3) of maternal origin. In the second family, with the male fertility not impaired, reciprocal t(9;17)(q11;q11) was observed in four members of the family.

Adult↗

PubMed1992

Cell line specific abnormalities in expression of PNA, SBA and L-PHA binding sites by carcinogen induced rat urothelial carcinomas.

Bladder tumor cell lines derived from male F344 rats treated with N-buthyl N-(4-hydroxybuthyl) nitrosamine (BBN) or N-[4-(5-nitro-2-furyl)-2-thiazolyl] formamide (FANFT) have been established in vitro and characterized with respect to histology, karyotype, myc and c-Ha-ras oncogene expression or mutation, anchorage-independent growth and tumorigenicity in nude mice. This unique model system comprising 13 cell populations was employed to study common events during development of carcinogen-induced urothelial neoplasia. Differential expression of malignant phenotypes by these cell lines prompted us to examine their expression of carbohydrate structures binding peanut agglutinin (PNA), soy bean agglutinin (SBA) or leukoagglutinin (L-PHA), which are known indicators of tumor progression in rodents and humans. In the present study we analyzed the patterns of glycoproteins reactive with PNA and L-PHA by Western blotting. We also estimated quantitative differences in lectin binding to surfaces of normal rat urothelium and tumor cell lines by flow cytometry. The patterns of PNA or L-PHA reactive glycoproteins expressed by tumor cells were different from that of normal urothelium in culture. They were also different amongst the tumor cells. A unique non-sialylated, PNA binding glycoprotein (117 kD) was seen in the case of the highly tumorigenic F5 cell line and absent in normal urothelium as well as in other tumor cell lines. Normal cells did not express glycoprotein 60 kD binding PNA (only after desialylation), which was found in lysates of some but not all transformed cell lines. A very high molecular weight (much greater than 200), perhaps mucin-like sialoglycoprotein was found in normal urothelium but not in most of the tumor cell lines. Four major L-PHA reactive bands (greater than 200, 190, 100, 80 kD approximately) were found in normal urothelium. Some of those bands were overexpressed or missing in materials isolated from different tumor cell populations. Total cell surface binding of SBA and PNA by different tumor cell lines was very heterogenous (167-2% that of normal urothelium). No simple correlation between expression of the lectin binding glycoconjugates by urothelial carcinoma cells and other known functional, phenotypic or genetic alterations was found. We were also unable to demonstrate carcinogen-specific changes in expression of lectin binding to these tumor cell lines. Thus we conclude that lectin binding patterns are cell line specific. This may reflect distinct pathways of progression of individual cell lines. The potential sources of phenotypic variability between the cell lines were discussed.

Animals↗

PubMed1991

Specific chromosome change associated with acquisition in vivo of tumorigenicity in carcinogen-induced rat urinary bladder carcinoma cells.

The correlation between chromosomal changes and tumorigenic potential of rat bladder epithelial cells was investigated. Seven cell lines were established from neoplastic urothelial cells derived from heterotopically transplanted rat bladders treated with topical application of one of two carcinogens, N-methyl-N-nitrosourea (MNU) or N-hydroxy-N-glucuronosyl-2-aminofluorene. Loss of the short arm of chromosome 3 was demonstrated in three of four lines tumorigenic in the nude mouse, but in none of three nontumorigenic lines. One of the three nontumorigenic cell lines (D44c) was treated further in vitro with MNU. All six tumorigenic, but none of the four nontumorigenic, morphologically altered cell lines derived from D44c demonstrated loss of the short arm of chromosome 3. These results suggest that chromosome 3 alterations may be associated with the tumorigenicity of carcinogen-induced rat bladder epithelial cells.

Animals↗

PubMed1991

Chromosomal characterizations of human nasal and nasopharyngeal cells immortalized by human papillomavirus type 16 DNA.

Cell lines NW-1 and NPC-N were established by transfection of human nasal and nasopharyngeal epithelial cells, respectively, with human papillomavirus type 16 (HPV-16) DNA. Additional treatment of NPC-N cells with mitomycin C gave rise to the cell line NPC-N-M. Chromosomal analysis showed that 40-47% of NW-1, NPC-N, and NPC-N-M cells had a near-tetraploid number of chromosomes and several chromosomal abnormalities. These cells showed evidence of gene amplification in the form of double minutes (dmins). In situ hybridization with HPV-16 DNA probe demonstrated that the virus was integrated at the 2q21 chromosomal region in NPC-N cells. Multiple integration sites within 1p36, 1q31-q32, 2p25, and 2q21 regions were observed in NW-1 cells. Although all of these immortal cells could grow in methylcellulose, none of them demonstrated tumorigenicity in nude mice.

Adult↗

PubMed1990

Oncogene expression of FANFT- or BBN-induced rat urothelial cells.

Proto-oncogene expression by cultured urothelial cells prepared from the bladders of male F344 rats that had been treated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]-formamide (FANFT) or N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were examined. Although all of the cultured cells showed varying degrees of anchorage-independent growth, only 9 of them were transplantable into nude mice. A Northern blot technique was employed for the detection of proto-oncogene transcripts. The c-Ha-ras transcripts were detected in all the cultured urothelial cells prepared from the carcinogen-treated rats and in normal urothelial cells. However, the transcript levels were several-fold higher in the former than in normal cells. Increased expression of p21, as determined by immunohistochemical techniques, was also observed in all the original bladder tissues from which the cultures were derived. c-myc transcripts were detected in the cells from carcinogen-treated rats but not in the normal cells. The presence of myc product in hyperplastic urothelial lesions and carcinomas of original bladder tissues was confirmed by immunohistochemical methods. Transcripts of mos, erb B, Ki-ras, abl and src were not detected. Since increased expression of c-myc and c-Ha-ras were present in both transplantable and non-transplantable cell lines, and the expression of p21 occurs in preneoplastic cells, this suggests that elevated expression of these 2 genes may be an early genetic event during bladder carcinogenesis in the rat and further alteration of these 2 genes or mutation of additional genes may be required for the completion of malignant transformation.

Animals↗

PubMed1990

Induction of DNA synthesis by sodium phenobarbital, uracil, and sodium saccharin in urinary bladder of the F344 rat.

DNA synthesis in urothelial cells was determined 2, 4, 6, 10, and 16 weeks following dietary administration of promoters of bladder tumors to weanling male F344 rats. The experimental groups were fed AIN-76A diet or this diet containing 0.15% sodium phenobarbital, 3% uracil, 5% sodium saccharin, 2% sodium bicarbonate, or a combination of 5% sodium saccharin and 2% sodium bicarbonate. Two other groups were given Wayne rodent chow alone or in combination with 5% sodium saccharin. A group of rats given a drinking water containing 0.01% N-butyl-N-(4-hydroxybutyl)nitrosamine served as a positive control. With the exception of phenobarbital which increased the labeling index but did not induce hyperplasia, all other compounds increased the labeling index and induced hyperplasia. The combination of sodium saccharin and sodium bicarbonate was more effective than either compound alone in increasing the labeling index. Sodium saccharin was equally active when incorporated in either the AIN diet or the Wayne rodent chow. The present results suggest that a fundamental mechanism of bladder tumor promotion may be due to an increased DNA synthesis which leads to an increased turnover rate of urothelial cells rather than hyperplasia. However, since sodium saccharin is a promoter when incorporated into the Wayne diet but not into the AIN diet, the ability to stimulate DNA synthesis may be an important but insufficient condition for promotion by saccharin.

Animals↗

PubMed1990

De novo direct tandem duplication of the short arm of chromosome 7(p21.1-p14.2).

We report on a 6-year-old boy with moderate developmental retardation and unusual dermatoglyphics. Cytogenetic analysis demonstrated a duplication of chromosome sub-region 7p21.2-p14.2. Confirmation of the specific duplicated region was determined by quantitative Southern blotting by using a DNA fragment previously localized to the portion of chromosome 7 thought to be duplicated. This patient did not have the internal malformations seen with other dup(7p) patients.

Blotting, Southern↗

PubMed1990

Activating missense mutations in Ha-ras-1 genes in a malignant subset of bladder lesions induced by N-butyl-N-(4-hydroxybutyl)nitrosamine or N-[4-(5-nitro-2-furanyl)-2-thiazolyl]formamide.

Urothelial cell cultures generated from urinary bladders from a series of N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)- or N-[4-(5-nitro-2-furanyl)-2-thiazolyl]formamide (FANFT)-treated Fischer 344 rats were examined for activating missense mutations in Ha-ras-1 genes. Our overall objective was to identify oncogene-activating mutations in this system and to determine what altered biological properties correlate with such genetic changes. The urinary bladders from the treated animals showed a spectrum of histopathologies, from simple hyperplasia to transitional cell carcinoma (TCC). Using restriction analysis, oligonucleotide hybridization, and DNA sequencing, we found that approximately 20% (3/14) of the bladder cell cultures had acquired oncogenic single-base substitutions in codon 61 of Ha-ras-1 genes (CAA----AAA or CGA). The donor bladder lesions for these three cultures, which also harbored the same ras-activating mutations, were all classified as stage A or B TCCs. However, four other TCCs also arising in this series were found to have normal Ha-ras genes. Whereas approximately half of the bladder cultures derived from the carcinogen-treated rats were nontumorigenic in athymic mice, the three cultures containing ras oncogenes were all highly tumorigenic (forming tumors within 5 wk of injection into athymic mice). These cultures also displayed a high degree of anchorage-independent growth and NIH 3T3-transforming activity in gene transfer assays. The nontumorigenic cultures were derived from bladder lesions that included three hyperplasias and three stage A TCCs. We conclude that ras-activating missense mutations were present in a malignant subset of bladder lesions induced by BBN or FANFT, but most of the lesions in this system appeared to involve genetic alterations elsewhere. Thus other oncogenes besides activated Ha-ras may apparently be associated with the same bladder histopathologies and transformation markers.

Animals↗

PubMed1990

A case of renal lymphangioma with a karyotype 45,X,-X,i dic(7q).

Cytogenetic analysis of a polycystic unilateral renal lymphangioma was performed by short-term culture and banding methods. The tumor's cells showed an isochromosome of the long arm of chromosome #7 and monosomy of X chromosome, whereas the peripheral lymphocytes stimulated with phytohemagglutinin showed a normal female karyotype, 46,XX. These karyotypic anomalies suggest that lymphangioma, although clinically benign, may have malignant potential.

Child, Preschool↗

PubMed1989

Chromosomal characteristics and malignancy of urothelial cells from carcinogen-treated rats.

Epithelial cells of bladders from male Fischer 344 rats that had been treated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) or N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) were cultured and examined for chromosomal changes, anchorage independence in vitro, and transplantability in vivo. Numerical but not structural changes of chromosomes were significantly greater in the FANFT group than in the BBN group. Urothelial cell lines that demonstrated prolonged life span and loss of anchorage dependency were established from 14 of these rats, but only nine of them demonstrated tumorigenicity in the nude mouse model. Two of these transplantable cell lines and R4909, a transplantable bladder cell line derived from a 3-methylcholanthrene-treated rat, have normal chromosomes. The present study demonstrates a carcinogen-related chromosome change in the urothelial cells, but the relationship between malignancy and specific chromosomal changes is not clear.

Animals↗

PubMed1989

Metabolism of aromatic amines: relationships of N-acetylation, O-acetylation, N,O-acetyltransfer and deacetylation in human liver and urinary bladder.

N-Acetoxyarylamines are reactive metabolites that are implicated in the initiation of the carcinogenic process by some N-substituted aryl compounds. The objective of this study was to explore the relationship between the production of these reactive species and N-acetylation (NAT), a reaction previously demonstrated to be polymorphic in the human. Human liver and urinary bladder mucosa samples were frozen within 4-8 h post mortem. These tissues were assayed for the (i) O-acetylation (OAT) of N-hydroxy-3,2'-dimethyl-4-aminobiphenyl (N-OH-DMABP) by acetyl CoA, (ii) intramolecular N,O-acetyltransfer (AHAT) of N-hydroxy-2-acetylaminofluorene (N-OH-AAF), (iii) NAT of 2-aminofluorene (2-AF) and p-aminobenzoic acid (PABA) by acetyl CoA and (iv) deacetylation of N-OH-AAF. Cytosolic AHAT and OAT showed partial inhibition by paraoxon. The ratio of paraoxon insensitive AHAT to OAT to NAT of PABA to NAT of 2-AF appears to be 1:2:11:22 using freshly made cytosols from frozen livers. Freezing of the cytosol resulted in extensive loss of activities. All four of these cytosolic enzyme activities exhibited a similar polymorphic response. Microsomal deacetylation showed a monomorphic response. Similar to the liver, urinary bladder epithelial cells also catalyzed the same reactions. However, the OAT and AHAT activities were detected mainly in microsomes. These data suggest that phenotypically rapid acetylators have a greater biochemical potential for the metabolic activation of aromatic amines by pathways that involve O-acetylation.

Acetylation↗

PubMed1988

Two mosaic cases with nonfluorescent Y chromosome analysed with Y-specific DNA probes.

Two cases of a nonfluorescent Y (Ynf) chromosome were diagnosed: one in a male, the other in a female. Both had similar complex mosaic chromosome constitutions with a 45,X cell line. DNA studies were applied in both cases for verification of the cytogenetic diagnosis. The results on the two patients were compared with data obtained from seven healthy men (46,XY), three healthy women (46,XX), two females with 46,XY karyotype, and from cell lines with 49,XXXXY and 48,XXXX chromosome constitution. The highly repetitive Y-specific DNA sequences located in the heterochromatic region of the long arm were absent in these patients. Differences in the composition of the euchromatic part of the Y chromosome were demonstrable in both patients. The highly repetitive Y-specific DNA sequences located in the heterochromatic region of the long arm were absent in these patients. Differences in the composition of the euchromatic part of the Y chromosome were demonstrable in both patients. The suggestion that the Ynf chromosome originates from a dicentric Y chromosome cannot be accepted as a complete explanation of the phenomenon, as it probably involves more complex molecular alterations of the abnormal Y chromosome. The presence of Ynf is associated with the presence of a 45,X cell line more often than in cases of simple Y chromosome deletions with the breakpoint localized in or below the Y euchromatin/heterochromatin junction.

Adult↗