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Biomedical subjects

G Bardi

Publications and source records attributed to G Bardi.

72 records · Page 4Linked to original sources
PubMed1993

Karyotypic abnormalities in tumours of the pancreas.

Short-term cultures from 20 pancreatic tumours, three endocrine and 17 exocrine, were cytogenetically analysed. All three endocrine tumours had a normal chromosome complement. Clonal chromosome aberrations were detected in 13 of the 17 exocrine tumours: simple karyotypic changes were found in five carcinomas and numerous numerical and/or structural changes in eight. When the present findings and those previously reported by our group were viewed in conjunction, the most common numerical imbalances among the 22 karyotypically abnormal pancreatic carcinomas thus available for evaluation turned out to be, in order of falling frequency, -18, -Y, +20, +7, +11 and -12. Imbalances brought about by structural changes most frequently affected chromosomes 1 (losses in 1p but especially gains of 1q), 8 (in particular 8q gains but also 8p losses), and 17 (mostly 17q gain but also loss of 17p). Chromosomal bands 1p32, 1q10, 6q21, 7p22, 8p21, 8q11, 14p11, 15q10-11, and 17q11 were the most common breakpoint sites affected by the structural rearrangements. Abnormal karyotypes were detected more frequently in poorly differentiated and anaplastic carcinomas than in moderately and well differentiated tumours.

Aged↗
PubMed1992

Trisomy 7 in nonneoplastic focal steatosis of the liver.

Cytogenetic analysis of short-term cultures of a nonneoplastic focal steatosis of the liver showed trisomy 7 as the sole chromosomal change. This finding, especially when viewed in light of previous reports describing +7 in nonneoplastic tissues, strongly suggests that trisomy 7 cannot be considered a tumor-specific abnormality when it occurs as the only change. The cell type in which +7 is present is not yet known.

Adult↗
PubMed1992

Nonrandom chromosomal rearrangements in pancreatic carcinomas.

Short-term cultures were initiated from 20 carcinomas of the pancreas, 17 of which could be successfully cytogenetically analyzed. In eight carcinomas, only normal karyotypes were detected, probably representing dividing stromal cells. Three cases had -Y as the sole anomaly, which also may have occurred in cells that do not belong to the tumor parenchyma. Massively rearranged karyotypes with modal chromosome numbers in the triploid (five cases) and diploid-triploid (one case) ranges were found in the remaining six carcinomas. Structural rearrangements, including deletions and unbalanced translocations, of the long arm of chromosome 6, involving bands q13 and q15 twice and q11 and q16 once, occurred in four tumors. All of these aberrations led to loss of chromosome material from 6q, always involving 6q15. Deletions and unbalanced translocations of the short arm of chromosome 1 also were found in four cases, affecting band p32 in three of them. In all four cases, the abnormalities resulted in loss of genetic material distal to 1p32. Chromosome 17 was involved in structural aberrations in three cases, twice as unbalanced translocations leading to loss of 17p material. Deletions of the short arms of chromosomes 3 and 8 were detected in two carcinomas. The most consistent numerical abnormalities were +2, +10, +11, +14, and tetrasomy 20, which were seen in all six cases. The findings suggest that structural rearrangements, or loss, of genes located on 1p, 3p, 6q, 8p, and 17p are of pathogenetic importance in pancreatic carcinogenesis.

Aged↗
PubMed1992

Trisomy 2 as the sole chromosomal abnormality in a hepatoblastoma.

Short-term cultures of a fine-needle aspirate from a hepatoblastoma were analyzed cytogenetically. Trisomy 2 was found as the sole abnormality, yielding the karyotype 47,XY, + 2/46,XY. Because trisomy for all or part of chromosome 2 has been described, although together with other aberrations, in seven of the 11 hepatoblastomas hitherto reported, the finding of + 2 as the only anomaly in the present case strongly indicates that additional chromosome 2 material is of pathogenetic significance in this tumor type.

Carcinoma, Hepatocellular↗
PubMed1992

Improved technique for short-term culture and cytogenetic analysis of human breast cancer.

Various growth media and procedures for tissue disaggregation and culturing were tested with regard to cell attachment, the type of cells to grow out, and the emergence of cytogenetically abnormal clones in cultures of 20 primary breast carcinomas. Clonal chromosome abnormalities were detected in 16 cases (80%). Our findings allow us to suggest a series of modifications of existing culturing and chromosome preparation techniques for breast cancer cytogenetic analysis. The improvements include: (1) combined mechanical and enzymatic disaggregation of the tumor samples, (2) initiation of short-term cultures in plastic flasks that have a Primaria-modified tissue culture surface or have been coated with Vitrogen 100, (3) use of serum-free growth medium, CDM-5, but with temporary (24 hours) enrichment with 20% FBS if rapid cell attachment is not achieved, (4) partial and sequential harvesting of the cultures, and (5) use of minimal volumes of hypotonic and fixative solutions during harvesting.

Aneuploidy↗
PubMed1992

Whole-arm t(1;16) and i(1q) as sole anomalies identify gain of 1q as a primary chromosomal abnormality in breast cancer.

Cytogenetic analysis of four ductal breast carcinomas revealed net gain of 1q in all tumors. In the first tumor, the only change was that one chromosome 16 was replaced by a derivative chromosome consisting of 16p and 1q. The same unbalanced whole-arm translocation was also found in the second tumor, as the only aberration in one of four abnormal clones. In the last two cases, which also were characterized by cytogenetically unrelated clones, an extra i(1q) was present in one clone in both tumors as the sole aberration. Our findings suggest that gain of 1q is a primary chromosomal abnormality in breast carcinomas, in the sense that it is an early event that precedes the acquisition of more complex changes.

Adenocarcinoma, Mucinous↗
PubMed1992

Recurrent chromosome aberrations in abdominal smooth muscle tumors.

Short-term cultures of four abdominal smooth muscle tumors, three leiomyosarcomas and one leiomyoma, were analyzed cytogenetically. A low-grade malignant, epithelioid leiomyosarcoma had a normal karyotype. The other two leiomyosarcomas had abnormal karyotypes; one was near-diploid, and the other was near-triploid. Structural rearrangements of the short arm of chromosome 16 and monosomies of chromosomes 14, 15, and 22 were observed in both tumors. When our cases and previously published abdominal leiomyosarcomas are viewed in conjunction, loss of chromosomes 14, 15, and 22 are the most frequent abnormalities. The leiomyoma, the second cytogenetically abnormal nonuterine leiomyoma reported to date, had a hyperdiploid karyotype with a chromosome number of 56 and structural rearrangements of chromosomes 9, 14, and 19. The only aberrations similar to those observed in the previously reported esophageal leiomyoma were trisomies of chromosomes 7 and 8.

Abdominal Neoplasms↗
PubMed1992

Cytogenetic findings in three primary hepatocellular carcinomas.

Short-term cultures of three primary hepatocellular carcinomas were cytogenetically analyzed. Case 1 displayed a normal karyotype. Case 2 had, in addition to cells with a normal male chromosome complement, a clone with -Y. In case 3, two abnormal clones were found, one with -Y and one with a highly aberrant karyotype: [formula: see text] Our results, collated with the findings in one previously published primary hepatocellular carcinoma and in three cell lines, suggest that structural changes of chromosomes 1 and 6, leading to loss of 1p and 6q material, and loss of chromosome 16 are frequent events in hepatocellular carcinogenesis.

Aged↗
PubMed1992

Chromosome aberrations and expression of ras and myc oncogenes in leiomyomas and a leiomyosarcoma of the uterus.

Twenty eight leiomyomas and one leiomyosarcoma were cytogenetically analysed and also examined for ras and myc oncoprotein expression. Chromosome alterations were found in seven leiomyoma cases. In four of them 12q14-15 was involved. P21 product of H-ras and P62 product of c-myc genes were detected in paraffin embedded parallel tissue sections. A high expression of H-ras was apparent in most tumors. C-myc expression was weak or negative in most leiomyomas with normal karyotype while on the contrary in three out of seven cases with abnormal cytogenetic findings the gene product stained moderately positive. Considerable chromosome abnormalities and oncogene overexpression were also identified in the leiomyosarcoma.

Adult↗
PubMed1991

Trisomy 7 in short-term cultures of colorectal adenocarcinomas.

Cytogenetic analysis of short-term cultures from six adenocarcinomas of the colon revealed trisomy 7 as a recurrent clonal chromosomal abnormality. In three tumors, +7 was the sole change. In the fourth carcinoma, two aberrant clones with simple numerical aberrations were detected; one with +7 and one with +3. Tumors 5 and 6 both displayed two completely different abnormal clones; one had numerous numerical and structural abnormalities and thus was undoubtedly representative of the cancer parenchyma, and the other had only +7. The karyotypic differences between the coexisting clones in the latter two cases seem to argue against an evolutionary scenario in which the karyotypically more complex clones have evolved from the clones carrying trisomy 7 only. Furthermore, in tumor 6 the metaphases with trisomy 7 were found in colonies of fibroblast-like cells whereas those with a large number of abnormalities grew in colonies of epithelial-like cells. The combined results indicate that mitoses with trisomy 7 as the sole chromosomal change do not represent the neoplastic parenchyma of colorectal adenocarcinomas.

Adenocarcinoma↗
PubMed1991

Chromosomal abnormalities in giant cell tumors of bone.

Cytogenetic analysis of short-term cultures from ten giant cell tumors of bone revealed clonal and nonclonal chromosome abnormalities in three tumors and nonclonal changes only in seven. None of the clonal aberrations, inv(21)(p11q21) in one tumor, +5 in another, and t(15q22q), dic(4;22)(p16;p1?), double minutes, dicentrics, and ring chromosomes present in three separate clones in the third tumor, were identical to previously reported clonal changes in giant cell tumors. Telomeric associations were found in five tumors. The telomeres of chromosome arms 19q and 15p were particularly frequently involved.

Adolescent↗
PubMed1991

Chromosome analysis of 96 uterine leiomyomas.

From September 1989 to May 1990, we attempted cytogenetic analysis on 96 uterine leiomyomas removed from 64 women. Of the 90 tumors in which analysis was successful, 59 had a normal karyotype while 31 had clonal abnormalities. The most common aberration (13 tumors) was 7q-, mostly del(7)(q21.2q31.2); in two tumors with +12 and t(12;14) as the primary abnormalities, the 7q- was obviously a secondary change since it was found only in a subclone. A t(12;14)(q14-15;q23-24) was detected in two tumors, complex aberrations involving both 12q14-15 and 14q23-24 were also present in two, and rearrangements of 12q without concomitant 14q changes were seen in another two myomas. Rearrangements of 6p were present in five tumors, and trisomy 12 was found in two. More than one abnormality could be detected in 17 leiomyomas. Evidence of clonal evolution in the form of subclones was found in eight tumors, all of which were cellular and had histologically detectable mitotic activity. In addition to their clonal complexity, these myomas also frequently exhibited clonal telomeric associations (four tumors) and ring chromosome formation (three tumors; twice affecting chromosome 1). Monosomy 22 occurred as a secondary abnormality in three tumors; it, too, may reflect a preferred pathway in the karyotypic evolution of uterine leiomyomas.

Chromosome Aberrations↗
PubMed1990

Complex chromosome rearrangements involving 12q14 in two uterine leiomyomas.

Cytogenetic analysis of short-term cultures from 10 uterine leiomyomas revealed normal karyotypes in 8 and clonal complex chromosome rearrangements in 2 tumors. In both leiomyomas with clonal abnormalities, 12q14, but not 14q22-24, was involved in translocations with 1q43 in one tumor and with 12q24 in the other. Additional chromosome abnormalities were found in both cases: 1-5 rings and monosomy of chromosome 9 in case 1, and complex numerical and structural abnormalities of chromosomes 1, 6-8, 11, 13, 16, 17, and 22 in case 2. The consistent cytogenetic rearrangement of 12q14 in uterine leiomyomas, sometimes without concomitant 14q changes, indicates that a gene of critical importance for leiomyoma development may be found in this band.

Adult↗
PubMed1990

High resolution mapping of consistent leiomyoma breakpoints in chromosomes 12 and 14 to 12q15 and 14q24.1.

A substantial percentage of uterine leiomyomas are cytogenetically characterized by consistent, clonal chromosome abnormalities, including t(12;14)(q14-15;q23-24) and other rearrangements of 12q14-15 that occur without any visible 14q changes. The partly similar banding characteristics of these two regions have hitherto precluded exact mapping of the 12q and 14q breakpoints to any particular band, let alone their assignment to subbands. In the series of four myomas presented here, in which one tumor had inv(12q), two t(12;14), and one a three-way t(7;12;14), we were able to achieve high resolution banding (550 band stage) of the rearranged chromosomes in several metaphases. This enabled us to assign a 12q breakpoint to 12q15 in all tumors and, in the three cases informative in this regard, the 14q breakpoint to 14q24.1. The more precise breakpoint mapping considerably narrows down the area that must be examined with molecular genetic methods in order to identify the gene loci that are rearranged in leiomyomas with 12q and 14q aberrations. It will also help determine to what extent leiomyoma rearrangements of 12q involve the same loci that are affected in 12q changes in other tumor types, e.g., in pleomorphic adenomas of the salivary gland, in lipomas, and in myxoid liposarcomas. At present it seems that the breakpoint in 12q may be cytogenetically identical in the three benign tumors, whereas it in myxoid liposarcomas appears to be more proximal.

Chromosome Aberrations↗
PubMed1990

Parallel karyotypic evolution and tumor progression in uterine leiomyoma.

Cytogenetic evidence of clonal evolution was detected in five uterine leiomyomas. In two tumors, two clones were found, the third tumor had four, the fourth had nine, and the fifth had 12 clones. The first tumor had trisomy 12 as the primary anomaly and a sideline that also contained a del(7)(q21q31). Both clones of the second tumor had three structural changes in common but differed by the presence in the more advanced clone of an inv(7)(q31q34). Two cytogenetically unrelated pairs of clones were seen in the third tumor. One clone had a stemline of 46 and an r(1); a sideline had developed through duplication of this clone. The other pair had a del(7)(q21q31) in common. The last two tumors both had t(12;14)(q14-15;q23-24) as the primary abnormality. They also had a high frequency of telomeric associations that involved certain chromosome arms only. One of the secondary changes in the fourth tumor was a del(7)(q21q31); the principal secondary change in the fifth case was a ring chromosome 1 of variable size in the different clones. The analysis of these five uterine leiomyomas and the collation of the results with previously obtained data lead us to conclude that del(7)(q21q31) is secondary to t(12;14) and + 12 in this tumor type, and that ring formation involving chromosome 1 material, often with duplication of segments, is a common phenomenon during clonal evolution. The fact that the tumors were classified as cellular and had an increased mitotic rate indicates a parallel development between histologically detectable tumor progression and cytogenetically recognizable clonal evolution in uterine leiomyomas.

Chromosome Aberrations↗
PubMed1989

Mixed lineage leukemia with cytogenetically unrelated abnormal clones.

We present a case of acute leukemia with morphologic, cytochemical, and immunophenotypic markers indicating that the population of blasts have characteristics of lymphoid and myelomonocytic origin. The cytogenetic study revealed the following mosaic abnormal karyotype: 46XX,dup(1)(q21----32)/46,XX,dup(11)(q13----25)/47,XX,trip(11) (q13----25),+der(17)t(17;?) (q24;?). The two clones involving #11 are obviously related. It is reasonable to assume that the third clone is an evolutionary result of the second one. Because no cytogenetic similarities were found among the first clone and the other two, we suggest that this mixed leukemia was of biclonal origin. To our knowledge, acute leukemia with mixed lineage characteristics and with the simultaneous presence of cytogenetically unrelated clones has not previously been reported.

Adult↗
PubMedDate not supplied

Influence of thyroid hormone on Sertoli cell protein metabolism in the prepubertal pig.

In order to better understand the role of thyroid hormones in testis development, the influence of tri-iodothyronine on protein metabolism of immature pig Sertoli cells has been investigated. Sertoli cells were isolated enzymatically from 2- to 3-week-old piglet testes and cultured in the presence or absence of tri-iodothyronine. Protein labelling was evaluated in Sertoli cell monolayers incubated in medium containing a tracer dose of [3H]leucine. The results demonstrate that thyroid hormone can directly stimulate the process of protein synthesis in immature porcine Sertoli cells, without significantly affecting the protein degradation rate; moreover thyroid hormone exposure results in a significant decrease of intracellular ATP level. The evidence that tri-iodothyronine can increase Sertoli cell protein synthesis, supplies additional evidence about the fundamental role of thyroid hormone in the regulation of growth and differentiation of the mammalian testis through a direct action on the Sertoli cells.

Adenosine Triphosphate↗