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PubMed1987

Down's syndrome and leukemia: epidemiology, genetics, cytogenetics and mechanisms of leukemogenesis.

The association of Down's syndrome and leukemia has been documented for over 50 years. Multiple studies have established the incidence of leukemia in Down's syndrome patients to be 10- to 20-fold higher than that in the general population. The age of onset for leukemia in these children is bimodal, peaking first in the newborn period and again at 3-6 years. This increased risk extends into adulthood. All cytogenetic types of Down's syndrome apparently predispose to leukemia. The proportion of acute lymphoblastic leukemia and acute nonlymphoblastic leukemia in patients with Down's syndrome is similar to non-Down's syndrome leukemia patients matched for age. There are case reports in which leukemia, Down's syndrome, and other chromosomal aberrations cluster within a family. In these kindreds, there may be a familial tendency toward nondisjunction. Congenital leukemia also occurs with increased frequency in Down's syndrome patients, and is characterized by a preponderance of acute nonlymphoblastic leukemia (similar to non-Down's syndrome patients). Transient leukemoid reactions have been observed in Down's syndrome patients, as well as in phenotypically normal children with constitutional trisomy 21 mosaicism. The transient leukemoid reactions are characterized by a high spontaneous remission rate. However, in some Downs syndrome patients with apparent transient leukemoid reaction, leukemia relapse following periods of spontaneous remission have been reported. Cytogenetic studies of leukemic cells in Down's syndrome patients show a tendency toward hyperdiploidy. Besides trisomy 21, there is no other specific cytogenetic abnormality that is characteristic of the leukemia cells in Down's syndrome patients. The possible mechanisms for leukemogenesis in Down's syndrome patients may involve factors at the levels of the organism, the organ/system, the cell, the chromosomes or the DNA.

Acute Disease↗

PubMed1988

Cytogenetic abnormalities in human small cell lung carcinoma: cell lines characterized for myc gene amplification.

Nine cell lines established from various malignant tissues of patients with small cell lung carcinoma (SCLC) were examined for chromosomal abnormalities and myc gene amplification. Cytogenetic studies revealed that all cell lines were aneuploid, often with a bimodal distribution with modal concentrations in the hypodiploid and hypertriploid range. With respect to chromosome #3, deletions of 3p were confined to six of nine SCLC "classic" lines. The region of overlap of the observed 3p deletions lies within 3p21-3p24 which is in agreement with previous assignments. Six of the nine lines tested with c-, N-, and L-myc probes showed an increase of between ten- and 100 fold in myc gene copy number. Coamplification of two or more of these genes was not observed in any cell line. Five of the six lines with myc gene amplification had cytogenetic markers of gene amplification either in the form of homogeneously staining regions (HSR) or double minutes (DM). Our results confirm that cytogenetically visible deletions of 3p are often present in cell lines established from patients with SCLC, and that mutually exclusive c-, L-, or N-myc gene amplification is also a common event in SCLC cell lines.

Carcinoma, Small Cell↗

PubMed1989

Cytogenetic analysis of two C-1300 murine neuroblastoma cell lines expressing discordant malignant behavior.

Cytogenetic analysis of two murine neuroblastoma cell lines that show different malignant expression revealed consistent differences in the chromosomal composition between the two lines. The MNB-T1 (high-malignancy) cell line showed increased modal chromosome number, presence of homogeneously staining regions (HSRs), double minutes (dmin) and evidence of secondary chromosomal events when compared with the MNB-T2 (low-malignancy) cell line, which did not express these cytogenetic characteristics. Several of the cytogenetic events that have occurred in these murine cell lines, such as HSRs, dmin, and chromosomal deletions, have also been reported in human neuroblastoma cell lines. When comparisons are made for the involvement of chromosomal regions known to be involved in human neuroblastoma, similar tumor specific regions seem to be involved in the homologous mouse chromosomes.

Animals↗

PubMed1989

Cytogenetic studies of 103 patients with acute myelogenous leukemia in relapse.

In order to investigate the cytogenetic patterns in relapsed acute myelogenous leukemia (AML), a clinical and cytogenetic follow-up of patients newly diagnosed for the Fourth International Workshop on Chromosomes in Leukemia (4IWCL) was evaluated at the 6IWCL. Information was received on 103 patients in relapse who were then classified into seven groups according to the diagnostic karyotype. These groups were: normal, t(8;21), t(15;17), +8, a single specific abnormality either numerical or structural other than those already listed, a single nonrandom or miscellaneous abnormality again either numerical or structural, and complex abnormalities. The patient's age, diagnostic FAB type, the number of relapses, the total survival time, and the karyotype in relapse were considered in each of these cytogenetic groups. The remission and survival rates were comparable in all groups except the +8 group, where patients relapsed earlier and had a shorter survival time. Multiple relapses occurred most frequently in the t(8;21) group, whereas none of the patients with t(15;17) relapsed more than once, although the total survival time was similar to the two groups. Thirty-nine percent of the patients relapsed with the same karyotype as at diagnosis. A more complex karyotype showing evolution was found in 53%, and 8% showed either a less-complicated karyotype or appeared to have reverted to normal. Numerical abnormalities in relapse frequently involved trisomy of chromosomes 8 and/or 21. There was a nonrandom development of 9q- with relapse in patients with t(8;21). A pericentric inversion of chromosome 4, and abnormality infrequently reported at diagnosis, was found in relapse in association with t(15;17), t(8;21), and +8 karyotypes. Changes considered to be typically secondary in nature involving 5q, 7q, and 12p were seen in only seven cases. Twenty-one patients who had an apparently normal karyotype at diagnosis remained normal in relapse, indicating that absence of clonal chromosome abnormality is a real observation in AML rather than a failure of detection.

Adolescent↗

PubMed1989

Complex cytogenetic aberrations in a well-differentiated chondrosarcoma.

The cytogenetic analysis of a well-differentiated (grade I) chondrosarcoma is presented. Despite a low-grade histopathology, metaphase preparations of tumor cells were characterized by numerous structural chromosome aberrations and a striking degree of genetic instability; the t(9;22)(q31;q12) that has been described recently in extraskeletal myxoid chondrosarcoma was not observed. This report suggests that chondrosarcomas may be heterogeneous cytogenetically. In chondrosarcoma, it appears that "high-grade" cytogenetic abnormalities do not necessarily engender a high-grade histology. These findings offer a possible explanation for the clinical aggressiveness of certain low-grade chondrosarcomas.

Aged↗

PubMed1989

First cytogenetic evidence of homozygosity for the retinoblastoma deletion in chromosome 13.

Retinoblastoma (Rb) provided the first model in which both normal alleles of a recessive gene had to be lost as a prerequisite for tumorigenicity. However, region q14 of chromosome 13 appears cytogenetically normal in the majority of Rb tumors, and no homozygotic deletion had previously been observed. High-resolution cytogenetics of an Rb tumor revealed a homozygotic deletion in bands q13.3-14.2 of chromosomes 13 in 35% of the cells and a heterozygotic deletion, involving the same region, in 17%. In one third of the cells, although random chromosome loss occasionally occurred, no specific anomaly was detected. The remaining cells showed either monosomy 13, tetraploidy, or an i(1p). Revealing a homozygotic deletion in subbands 14.1 and 14.2 of chromosomes 13 provides the first cytogenetic evidence of the two somatic mutations considered essential to inactivate the Rb gene. These results allow insight into the succession of events necessary for tumor development.

Chromosome Banding↗

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↗

PubMed1989

A cytogenetic study of 53 human gliomas.

Cytogenetic studies were performed on human glioma samples obtained by stereotactic biopsy, stereotactic craniotomy, or routine craniotomy. Using in situ culture and robotic harvesting techniques, we obtained suitable metaphases in 50 (94%) of 53 tumors, including 28 diffuse astrocytomas, four juvenile pilocytic astrocytomas, two gliosarcomas, three other miscellaneous astrocytomas, eight oligodendrogliomas, four mixed oligodendroglioma-astrocytomas, and four ependymomas. Cytogenetic studies were performed only on primary cultures; the mean culture time was 9.6 days (range 1-31 days). One or more chromosomally abnormal clones were observed in 35 (66%) tumors. Eleven (21%) other specimens had random nonclonal chromosome abnormalities. In four (8%) specimens, no chromosome abnormalities were noted. The results of this study suggest that grade 3 and 4 tumors are more likely to contain an abnormal clone than tumors of grade 1 or 2 (p less than 0.01). The most common numeric chromosome abnormalities were -6, +7, -10, -13, -14, -15, -18, and -Y. The most common structural abnormalities involved 1p, 6q, 7q, 8p, 9p, 11p, 11q, 13q, and 19q. Four tumors had two or more independent clones and ten contained subclones demonstrating karyotype evolution. With in situ culture and robotic harvesting techniques, cytogenetic studies can be successful on nearly all human gliomas, including those derived from small stereotactic biopsies.

Adolescent↗

PubMed1990

Hypodiploid, pseudodiploid, and normal karyotypes prevail in cytogenetic studies of medullary carcinomas of the thyroid and metastatic tissues.

Medullary carcinoma of the thyroid (MCT), often a dominantly inherited neoplasm, derived from intrathyroid C-cells of neural crest origin, is one of the solid tumors least studied cytogenetically. The cells are difficult to grow in culture, only two cell lines having ever been established. Cytogenetic studies of only 5 tumors have been reported previously. In this paper we report on the cytogenetic analyses of 8 specimens of primary and/or metastatic MCT tumor tissue from 6 patients with familial disease, including more recent metastatic tumors in lymph node and femur of a patient whose thyroid and earlier lymph node metastases were described previously. Some of these specimens were harvested sequentially over time. Hypodiploid or diploid modal numbers prevailed with normal, pseudodiploid, or hypodiploid karyotypes.

Adolescent↗

PubMed1990

An inter-Nordic prospective study on cytogenetic endpoints and cancer risk. Nordic Study Group on the Health Risk of Chromosome Damage.

To investigate whether high rates of chromosomal aberrations (CAs), sister chromatid exchange (SCE), or micronuclei(MN) in peripheral lymphocytes indicate an increased risk for subsequent cancer, a prospective cohort study of 2,969 subjects cytogenetically examined between 1970 and 1988 in four Swedish, two Finnish, and two Norwegian laboratories was initiated. To standardize for the interlaboratory variation, the results of the three cytogenetic endpoints were trichotomized for each laboratory into "low" (1st to 33rd percentile), "medium" (34th to 66th percentile), and "high" (67th to 100th percentile]. Thirty-four cancers had been diagnosed in the cohort during the observation period (1970 to 1985). The point-estimates of the standardized morbidity ratio (SMR) in the three CA strata were 90, 92, and 180, respectively. This trend for a positive association was not statistically significant (p = 0.06). There was no significant trend between SMR and the trichotomized rates of SCE. In the subcohort examined for MN only two cases of cancer had been diagnosed until now. If subjects with "high" frequencies of CA or SCE have a two-fold (or greater) risk of developing cancer as compared with individuals who have "medium" or "low" frequencies, we estimate that there is a likelihood of 80% and 70%, respectively, that this will be detectable as significant (p less than or equal to 0.05) differences after a further follow-up period of 5 years. Weaker associations between cancer risk and the cytogenetic endpoints would not be possible to evaluate until even later follow-ups.

Chromosome Aberrations↗

PubMed1990

Cytogenetic studies of human T-cell leukemia virus type I carriers. A family study.

Recently, the chromosome 14q11 anomaly has been reported to be specific to adult T-cell leukemia (ATL), and this anomaly has also been confirmed in the preleukemic state of adult T-cell leukemia (pre-ATL) patients. Because the cytogenetic abnormality at the stage of human T-cell leukemia virus type I (HTLV-I) carrier remains uncertain, we performed cytogenetic studies of lymphocytes stimulated with phytohemagglutinin in three HTLV-I carriers and three non-HTLV-I carriers in an ATL family. As a result, in three HTLV-I carriers, four of 311 cells examined (1.3%) had chromosome 14q11 anomaly. However, in three non-HTLV-I carriers, none of 260 cells examined had chromosome 14q11 anomaly. These results suggest that chromosome 14q11 anomaly is already present at the stage of HTLV-I carrier and seems to be an important cytogenetic clue to the pathogenesis of ATL.

Adult↗

PubMed1990

Cytogenetic abnormalities and leukemic transformation in hydroxyurea-treated patients with Philadelphia chromosome negative chronic myeloproliferative disease.

Eighty-one consecutive hydroxyurea-treated patients with Philadelphia (Ph) chromosome negative chronic myeloproliferative disease were followed prospectively from 1981 to 1989; 35 of them had polycythemia vera, 32 had essential thrombocythemia, 12 had myelofibrosis, and 2 had myeloproliferative syndromes. The 81 patients were treated with hydroxyurea for a total of 3,804 months during the observation time. Only three patients had been treated with alkylating agents or 32P before start of hydroxyurea treatment. Four patients transformed into acute myeloid leukemia or myelodysplastic syndromes; three of these patients had essential thrombocythemia, and one had a myeloproliferative syndrome. Two patients died of solid cancers. Five out of 53 evaluable patients (9%) had pretreatment clonal cytogenetic abnormalities involving chromosomes 1, 9, 20, and 21. At follow-up, during or after hydroxyurea treatment, 15% had cytogenetic abnormalities, an unexpectedly low frequency compared to the previously reported frequency in patients with polycythemia vera treated with alkylating agents. None of our patients who developed cytogenetic clonal changes during hydroxyurea therapy had polycythemia vera. However, follow-up is too short to draw any conclusions about the mutagenic potential of hydroxyurea compared to alkylating agents.

Adult↗

PubMed1990

Cytogenetic and molecular approaches of polyploidization in colorectal adenocarcinomas.

We present the cytogenetic analysis of 23 cases of polyploid colorectal adenocarcinomas. We took advantage of the high intratumoral heterogeneity of the karyotypes to identify clones, subclones, and cell-to-cell variations. This allowed us to reconstruct the chromosomal evolution of each tumor and to propose a schema of the chromosomal changes in relation to the endoreduplication process. All but one case were characterized by a relative deficiency of chromosomes 17p and 18. Other deficiencies affecting the late-replicating X, and to a lesser degree, 1p, 5q, 14, 15, 8p, 10, 21, and 4, and excesses affecting the early-replicating X, 8q, 13, 16, 17q, and 11 were frequently associated. This pattern of imbalances is very similar to that of the monosomic type previously described in near-diploid tumors. The pattern of the 23rd tumor corresponded to those of the trisomic type tumors. These data largely confirm the existence of two distinct processes of chromosomal evolution in colorectal adenocarcinomas, with a strong tendency to undergo endoreduplication for the monosomic type near-diploid tumors. To correlate cytogenetic and molecular data, allelic losses analyses were investigated for probes of chromosomes 17p and 18. In all 12 informative tumors, a loss of heterozygosity for probes of the short arm of chromosome 17 indicated the occurrence of a rearrangement of chromosome 17 before the endoreduplication. The same was true for allelic losses for probes of chromosome 18 found in 11 of 12 informative tumors. The correlation between cytogenetic and molecular data is thus excellent and indicates that losses of 17p and 18 are early events in the tumor process.

Adenocarcinoma↗

PubMed1991

Similar cytogenetic abnormalities in two cases of plasma cell leukemia.

Plasma cell leukemia (PCL) is a very rare disease. We report two cases of PCL with complex chromosomal abnormalities: long arm trisomy and short arm partial monosomy of chromosome 1, a marker derived from chromosome 8, and monosomy 13 were found in both cases; other additional chromosome abnormalities were also present in each case. Bastard et al. reports two similar cases in this issue. Cytogenetic studies in PCL have seldom been reported in the literature: chromosomal abnormalities are most often complex: chromosomes 1, 8, 11, 13, and 14 are those most frequently involved. Such cytogenetic findings are observed in advanced multiple myeloma. Cytogenetic, clinical, and immunological findings observed in PCL and the advanced stage of multiple myeloma are arguments for the single origin of pathogenesis.

Adult↗

PubMed1991

Cytogenetic analysis of two sacral chordomas.

Cytogenetic analysis of two sacral chordomas revealed two distinct abnormal clones in one of the cases: 44,XY,t(1;3)(q42;q11), -2,der(7)t(2;7)(q23;q32), -21 and 46,X,t(Y;8)(q12;q22), t(1;14)(p34;q32),t(5;10)(q13;p11). All cells analyzed from the second case were cytogenetically normal. To the best of our knowledge, chordomas have not previously been subjected to cytogenetic analysis.

Aged↗

PubMed1992

Cytogenetic biclonality in malignant hematologic disorders.

Generally, malignant hematologic disorders have been believed to be of monoclonal origin. However, cytogenetically unrelated clones have been reported in some disorders including one case of acute leukemia (AL), one of acute lymphoblastic leukemia (ALL), one of acute myeloblastic leukemia (AMMoL), and five of myelodysplastic syndromes (MDS). The most frequent chromosome abnormality was trisomy 8 (75%), followed by trisomy 21 (37.5%, including tetrasomy 21) and trisomy 11 (25%). Two patients showed both trisomy 8 and 11, one also had trisomy 21 (triclonal). One patient showed two cytogenetically distinctive clones in which one was 47,XY,+8, related to myeloid cells, and the other had a del(6q) and del(9p), suggesting lymphoid cells. One patient we report and 5 from the literature had two unrelated clones with trisomy 8 and deletion of the long arm of chromosome 5 (5q-); all had MDS. Review of our records showed that 11 patients with both trisomy 8 and 5q- in the same abnormal karyotype (not biclonal) had AL, i.e., 10 of acute nonlymphocytic leukemia (ANNL) and one of chronic myelogenous leukemia (CML) in blastic crisis. These findings suggest that cytogenetically unrelated clones may indicate hematopoietic biclonality.

Acute Disease↗

PubMed1992

Cytogenetic features of neonatal leukemias.

We reviewed a series of 41 neonatal leukemias (NL), including published cases karyotyped by banding techniques, but excluding Down syndrome-associated cases and analyzed distribution of cytogenetic anomalies with respect to other clinical variables and outcome. The most frequent chromosomal changes in this age group involve rearrangements of 11q23, which is correlated with high white blood cell (WBC) count at onset and type of leukemia. A discrete heterogeneity of cytogenetic abnormalities is also evident, however, possibly reflecting other specific pathways in NL development. With respect to prognosis, cytogenetic abnormalities are a strong indicator of poor prognosis.

Chromosome Aberrations↗

PubMed1992

Analysis of a giant marker chromosome in a well-differentiated liposarcoma using cytogenetics and fluorescence in situ hybridization.

Well-differentiated liposarcomas (LPS) are cytogenetically very complex, characterized by giant marker chromosomes, ring chromosomes, and telomeric associations. We report a case of well-differentiated LPS in which the only cytogenetic anomaly was an additional giant marker. In an attempt to identify the origin of this marker, centromeric probes (chosen on the basis of the morphology of the marker) to chromosomes 1,2,3,4,6,7,8,9,10,11,12,16,17, and X and a shared satellite probe for chromosomes 1,5, and 19, were used with fluorescence in situ hybridization (FISH). This was successful at eliminating certain chromosomes as candidates for centromeric trisomy but could not identify the origin of the marker. This case is unusual in that it does not conform to the typical cytogenetic pattern for well-differentiated LPS and is the first known example with an apparently normal diploid karyotype with only one additional change.

Aged↗