Cytogenetic characterization of selected small round cell tumors of childhood

Small, round, blue-cell tumors (SRCT), including rhabdomyosarcoma, Ewing's sarcoma of bone and soft tissue, mesenchymal chondrosarcoma, small cell osteosarcoma, hemangiopericytoma, neuroblastoma, peripheral neurectodermal tumor (peripheral neuroepithelioma of bone and soft tissue), and the malignant small cell tumor of the thoracopulmonary region described by Askin (Askin's tumor), are often difficult to distinguish by light microscopy. We have evaluated the cytogenetics of these tumors by studying 24 tumor explants in short-term culture and 22 tumor cell lines. In Ewing's sarcoma (a tumor of unknown histogenesis), and in peripheral neuroepithelioma and Askin's tumor (tumors with evidence of neural origin), we have observed an indistinguishable t(11;22) translocation.

Methodologic advances in the cytogenetic analysis of human solid tumors

The major obstacle to successful cytogenetic analysis of human solid tumors is the acquisition of sufficient numbers of good quality metaphases for detailed cytogenetic analysis. At present, no single methodologic approach has been proven to provide successful chromosomal analysis of all human solid tumors. The technical aspects of cell culture, chromosome harvesting, and chromosome banding were the focus of considerable discussion during the First Workshop on Chromosomes in Solid Tumors. This report provides summaries of several technical protocols, emanating from several different laboratories, which have contributed to successful chromosome analysis of a variety of human solid tumors.

Amplification of DNA sequences in human multidrug-resistant KB carcinoma cells

Four KB carcinoma cell lines selected independently for resistance to either colchicine, adriamycin, or vinblastine were studied. All cell lines showed high levels of resistance to the selecting drug and cross-resistance to the other drugs and to actinomycin D. Double-minute chromosomes could be identified on chromosomal spreads of these multidrug-resistant KB cell lines. Amplification of specific DNA sequences was demonstrated by using the technique of in-gel renaturation. All the cell lines share common amplified sequences. There are also amplified sequences that are specific for each cell line. A revertant cell line that has reacquired drug sensitivity has lost its amplified sequences. Specific probes obtained by cloning amplified sequences from the cell line selected in vinblastine recognize amplified sequences in all the resistant lines. The presence of common amplified sequences in these cell lines is strong evidence for the importance of these regions in multiple drug resistance.

Patients with small-cell lung cancer treated with combination chemotherapy with or without irradiation. Data on potential cures, chronic toxicities, and late relapses after a five- to eleven-year follow-up

We assessed the outcome in 252 patients with small-cell lung cancer 5 to 11 years after treatment with combination chemotherapy, with or without chest and cranial irradiation, in National Cancer Institute therapeutic trials from 1973 through 1978. Twenty-eight patients (11%) survived free of cancer for 30 months or more. Fourteen patients remain alive without evidence of cancer beyond 5 years (range, 6.4 to 11.3 years), and 7 patients have returned to a lifestyle similar to that before diagnosis. The other 14 patients who were cancer-free at 30 months have developed cancer or died; 6 patients had a relapse, 4 developed or died from non-small-cell lung cancer, and 4 died of unrelated causes. A few patients with small-cell lung cancer (5.6%) may be cured. Thirty-month, cancer-free survival is insufficient to show a cure. Although late toxicities are troublesome, they do not outweigh the benefits of prolonged survival and potential for cure with modern aggressive therapy in small-cell lung cancer.

Correlations between intercalator-induced DNA strand breaks and sister chromatid exchanges, mutations, and cytotoxicity in Chinese hamster cells

Intercalator-induced DNA strand breaks in mammalian cells represent topoisomerase II:DNA complexes trapped by intercalators. These complexes are detected as protein-associated DNA single-strand breaks (SSB) and DNA double-strand breaks (DSB) by filter elution. Using Chinese hamster lung fibroblasts (V79 cells) that were treated for 30 min with various concentrations of 4'-(9-acridinylamino)methanesulfon-m-anisidide or 5-iminodaunorubicin, we measured DNA strand breaks (SSB and DSB), sister chromatid exchanges (SCE), mutations at the hypoxanthine:guanine phosphoribosyltransferase locus, and cell killing. Further, we correlated DNA strand breakage with the three other parameters. Both drugs induced SCE, mutations, and cell killing at concentrations which also produced reversible DNA strand breaks. While the quantity of DSB correlated with SCE, mutations, and cytotoxicity for both drugs, we found more SCE, mutations, and cytotoxicity per SSB in cells treated with 5-iminodaunorubicin than in those treated with 4'-(9-acridinylamino)methanesulfon-m-anisidide. These data show that the DSB (but not the SSB) induced by 4'-(9-acridinylamino)methanesulfon-m-anisidide and 5-iminodaunorubicin at DNA topoisomerase II binding sites correlated closely with SCE, mutations, and cell killing and could therefore be responsible for their production.

In vivo incorporation of bromodeoxyuridine into proliferating cells in the marrow and its effects on granulocyte-macrophage progenitor cells

Bromodeoxyuridine (BUdR), a potential radiosensitizing drug, was given by intravenous infusion at 650-1000 mg/m2/day for up to 12 days. In vivo incorporation into human bone marrow was assayed by differential chromatid staining as well as by comparison of in vitro radiation survival curves of granulocyte-macrophage progenitor cells scored at both day 7 and day 14. Although a difference was found in the radiation survival of control (untreated) day-7 progenitor cells (Do = 1.39 Gy) and day-14 progenitor cells (Do = 0.89 Gy), a similar degree of in vitro radiosensitization was found for BUdR-treated bone marrow progenitor cells scored at day 7 and day 14. The culture technique provided a bioassay for the in vivo action of BUdR. BUdR treatment produced transient moderate myelosuppression that probably resulted from BUdR incorporation into normal marrow cells.

Cytogenetic studies in human T-cell lymphoma virus (HTLV)-positive leukemia-lymphoma in the United States

Cytogenetic studies were conducted on fresh and cultured cells from 11 patients with human T-cell leukemia virus-associated adult T-cell leukemia-lymphoma. Clones with abnormal karyotypes were detected in 9 of the 11 patients. Chromosome numbers were near-diploid in cells from all but 1 patient who also had a tetraploid clone. The chromosome abnormalities in these cells were extensive; numerous complex structural changes were seen in every chromosome pair. Structural abnormalities occurred most frequently in chromosome 6. The 6 patients with chromosome 6 deletions had breakpoints at bands q11, q13, q16q23, q21q23, q22q24, and q23q24. The characteristic clinical features of these 6 patients were aggressive course, short survival, poor response to chemotherapy, high white blood cell counts, hypercalcemia, and bone lesions, whereas cytogenetically abnormal patients without chromosome 6q deletions tended to have a more indolent course. The precise role of the 6q deletion cannot be established with certainty from these data. However, this abnormality appears to occur with a greater than expected frequency in this large cell aggressive lymphoma, in association with hypercalcemia and lytic bone lesions.

Acute megakaryoblastic leukemia in childhood

Routine morphologic and cytochemical study of the leukemic cells of a 13-month-old child did not permit definitive determination of either a lymphoid or a myeloid cell origin. However, ultrastructural cytochemical analysis revealed platelet peroxidase (PPO) reactivity. The malignant cells expressed PPO in both unfixed and fixed preparations. PPO was observed in the perinuclear space and reticulum but not in the Golgi saccules. In a 1% glutaraldehyde, 1% formaldehyde solution known to inhibit PPO but not myeloperoxidase, no reaction product was observed. The demonstration of PPO activity in these undifferentiated cells established their megakaryoblastic lineage. Further studies including DNA flow cytometry confirmed that these cells were megakaryoblasts. This study demonstrates that megakaryoblastic malignancy may occur as an acute leukemia of childhood and emphasizes the value of ultrastructural cytochemistry in cases of acute leukemia which defy routine classification. Abnormalities of chromosome 21 were present in our patient as in four previous cases of megakaryoblastic leukemia in childhood. The nonrandomness of chromosome 21 involvement in this disease should therefore be considered.

Cytogenetic effects of amsacrine on human lymphocytes in vivo and in vitro

Amsacrine (m-AMSA) is presently being utilized in phase I-II studies at the Medicine Branch, National Cancer Institute, National Institutes of Health (Bethesda, MD), and is being administered as a continuous infusion to patients with progressive malignancy after conventional therapy. In the present study, we examined the effects of this drug, in vivo and in vitro, on chromosomal morphology and the frequency of sister chromatid exchange (SCE) induction in human peripheral blood lymphocytes. In the in vivo studies, eight patients receiving 30 mg/m2/day of m-AMSA by continuous infusion showed increased levels of chromosomal aberrations, up to a maximum of 14% (median; range, 10%-24%) at 96 hours compared to 1% (median; range, 0%-4%) in the control group; no increase was noted in SCE frequencies. In vitro studies of normal human lymphocytes with various concentrations of m-AMSA, including doses comparable to those used in vivo, showed both increased levels of chromosomal aberrations, ranging from 8% to 100%, and increased SCEs, ranging from 1.5 times the normal at the lowest concentration studied (0.005 microgram/ml) to 12 times the normal (0.25 microgram/ml). In correlating SCEs with breaks in the in vitro studies, it was found that two-thirds of the total breaks occurred at SCE points; this indicates a close relationship between the events leading to these two types of aberrations. In vitro isotope incorporation studies showed inhibition of both RNA and DNA syntheses but no significant inhibition of protein synthesis; at a dose of 5.0 micrograms/ml, RNA synthesis was 80% inhibited and DNA synthesis was 60% inhibited after 36 hours of incubation with m-AMSA. The difference in the results between in vitro and in vivo SCE studies may be due to possible DNA repair in the in vivo-treated lymphocytes in m-AMSA-free medium in vitro, a process not available to the in vitro-treated cells.

Burkitt's lymphoma in AIDS: cytogenetic study

Cytogenetic studies were done in two cases of Burkitt's lymphoma in homosexual individuals with possible acquired immune deficiency syndrome (AIDS). The chromosomal abnormalities found are consistent with those previously described in the nonendemic form of Burkitt's lymphoma, with one of the two patients having the variant translocation, t(8;22). The production of the kappa light chain immunoglobulin by the tumor cells from the patient having t(8;22) and the occurrence of the different sites of translocation of the duplication of 1 q in the second patient are unusual findings. Whether there is an increase in the incidence of the variant translocation t(8;22) is yet to be determined.

Cytogenetic studies in ovarian cancer

Cytogenetic studies of ovarian cancer have been conducted in the Medicine Branch, NCI, National Institutes of Health for 5 years. A total of 72 patients were studied by direct preparation and/or 1- to 3-day short-term culture of ascites (86 samples), pleural fluid (4 samples), and tumor (2 samples). Repeat examinations (1-24 months later) were performed in 7 of the 72 patients. Forty-four patients (62%) were successfully analyzed with banding techniques: 6 patients had adenocarcinoma, 7 had serous adenocarcinoma, 13 had serous papillary adenocarcinoma, 7 had serous papillary cystadenocarcinoma, 2 had mucinous adenocarcinoma, 6 had undifferentiated or poorly differentiated adenocarcinoma, 1 had clear cell adenocarcinoma, and 2 were not classified. Of these 44 patients, 29 had received prior chemotherapy, 14 were untreated, and in 1 patient the treatment status was unknown. Aneuploidy was observed in all patients and there was considerable variation in the chromosome numbers (even within single samples), often ranging from diploidy to triploidy to tetraploidy. All 44 patients had numerical abnormalities and 39 had structural abnormalities. The chromosomes most frequently involved in structural abnormalities (in decreasing order according to the number of patients involved) were #1, #3, #2, #4, #9, #10, #15, #19, #6, and #11; the least involved chromosomes were #21 and #5. Clone formation and the number of chromosomes involved in structural abnormalities increased with duration of disease and were more extensive in patients treated with chemotherapy than in patients treated with surgery alone. Our data did not show a deletion of chromosome #6 (6q-) to be specific for ovarian cancer.

Conversion of a stem cell leukemia from a T-lymphoid to a myeloid phenotype induced by the adenosine deaminase inhibitor 2'-deoxycoformycin

Selective failure of lymphoid development occurs in genetic deficiency of adenosine deaminase (ADA). We examined the in vivo effects of a potent inhibitor of ADA, 2'-deoxycoformycin, which was used to treat a patient with refractory acute leukemia. Unexpectedly, within 7 days of starting treatment, the leukemic phenotype underwent complete conversion from T lymphoblastic to promyelocytic, with kinetics that suggested a precursor-product relationship between the two cell populations. Pretreatment T lymphoblasts and posttreatment promyelocytes had the same abnormal karyotype. Upon culture in vitro, the former transformed spontaneously over several weeks into mature myeloid cells. We conclude that the leukemia arose from a multipotent stem cell capable of both lymphoid and myeloid differentiation. Effects of ADA inhibition on leukemia cells during treatment included expansion of the deoxyadenosine nucleotide pool and accumulation of S-adenosylhomocysteine, a potent inhibitor of S-adenosylmethionine-dependent methylation. The influence of these changes on the leukemic phenotype is discussed in terms of (i) selective cytotoxicity to T lymphoblasts, which accumulated deoxyadenosine nucleotides more efficiently than did the patient's promyelocytes during in vitro incubation with deoxycoformycin plus deoxyadenosine, and (ii) induction of an altered program of differentiation.

Synthesis of kappa light chains by cell lines containing an 8;22 chromosomal translocation derived from a male homosexual with Burkitt's lymphoma

Three cell lines were derived from a homosexual patient with probable acquired immunodeficiency syndrome and Burkitt's lymphoma. The cell lines produce an unusual strain of Epstein-Barr virus which will both transform cord blood lymphocytes and induce early antigens in Raji cells. Translocations between chromosomes 8 and 22 have occurred in all three lines, but the cells synthesize immunoglobulin M with light chains of the kappa type, in contrast to the usual concordance between a translocation involving chromosome 22 and lambda chain synthesis. Both kappa genes and one lambda gene are rearranged. These findings indicate either that translocation may occur as a separate event from immunoglobulin gene rearrangement or that the proposed hierarchical sequence of immunoglobulin gene rearrangements is not always adhered to. The data also imply that in cells containing a translocation between the long arm of chromosome 8 and a chromosome bearing an immunoglobulin gene, alteration of cellular myc expression may occur regardless of the immunoglobulin gene that is expressed.

Characterization of a human ovarian carcinoma cell line (NIH:OVCAR-3) with androgen and estrogen receptors

A cell line, NIH:OVCAR-3, has been established from the malignant ascites of a patient with progressive adenocarcinoma of the ovary after combination chemotherapy with cyclophosphamide, Adriamycin, and cisplatin. OVCAR-3 grows as a cobblestone-like monolayer with foci of multilayering, is tumorigenic in athymic mice, clones in agarose, and has an abnormal karyotype which includes a homogeneous staining region and a double minute chromosome. The cultured cells and xenografts contain cytoplasmic androgen- and estrogen-binding macromolecules with the specificity of the respective steroid hormone receptors. These components have sedimentation coefficients of 7 to 9S in low-salt sucrose-density gradients, have dissociation constants of 250 and 9.6 pM, and are present at concentrations of 30 and 28 fmol/mg cytosol protein characteristic of androgen and estrogen receptors, respectively. OVCAR-3 is resistant in vitro to clinically relevant concentrations of Adriamycin (5 X 10(-8) M), melphalan (5 X 10(-6) M), and cisplatin (5 X 10(-7) M) with survival compared to untreated controls of 43, 45, and 77%, respectively. Furthermore, there are multiple histological similarities between the patient's original tumor, the cell line, and the transplantable tumor. These data indicate that OVCAR-3 may be of use for investigations as to the significance of androgens and estrogens and the mechanisms of cytotoxic drug resistance in ovarian cancer.

Lymphoid blast crises of chronic myelogenous leukemia represent stages in the development of B-cell precursors

The origin and stage of differentiation of the blast-crisis cells in chronic myelogenous leukemia have remained uncertain. Because immunoglobulin heavy-chain and light-chain genes must undergo a DNA rearrangement during B-cell development but rarely do so in human non-B-cell lineages, we examined these genes in 18 episodes of chronic myelogenous leukemia. In eight of nine episodes of lymphoid blast crisis, heavy-chain genes were rearranged, and in three, rearrangements in light-chain genes were also present. In contrast, cells from chronic myeloid, myeloid blast, and erythroid-like phases retained germ-like immunoglobulin genes. The observed phenotypic markers and gene configurations revealed that most lymphoid blast crises represent stages of development of B-cell precursors. In two separate episodes of lymphoid crisis, cells from a single patient possessed identical heavy-chain but different light-chain-gene configurations. Thus, the precursor cells that monoclonally expand to produce a lymphoid crisis are capable of immunoglobulin-gene rearrangements and represent discrete steps in early B-cell maturation.

Cytogenetic studies of human breast cancer lines: MCF-7 and derived variant sublines

Cytogenetic studies of the human breast cancer cell line MCF-7 and the sublines derived from it demonstrated extensive aneuploidy with both numerical and structural abnormalities and a wide range of heteroploidy. Detailed G-banding analyses showed that loss of marker chromosomes was a rare event, while formation of additional structural abnormalities was very common in these long-term cultures. All chromosomes were involved in these abnormalities. Loss of a morphologically normal X-chromosome may be related to the loss of estrogen receptors in these cell lines. With the exception of one subline, all cell lines had a short homogeneously staining region (HSR) on chromosome 7. Although the parent MCF-7 line had tetrahydrofolate dehydrogenase levels within the normal range, a lengthened HSR has been found in MCF-7 lines that are resistant to methotrexate. This observation strongly favors the association of an increased level of tetrahydrofolate dehydrogenase with HSR. In conclusion, the inherent genetic instability in this group of related cell lines may explain the heterogeneity found in this tumor. Continuous chromosomal rearrangements and numerical changes may reflect an ongoing process of selection and adaptation in these cell lines established from a breast carcinoma and may be characteristic of the aggressiveness of this neoplasm.

Diagnostic and biological implications of flow cytometric DNA content analysis in lung cancer

Flow cytometric DNA content analysis, performed on clinical specimens from patients with lung cancer, was compared with clinical features, histological and/or cytological examination of the same specimen and, in some instances, to chromosome analysis and repeat DNA content analysis of short-term cultures. Tumors from 85% of non-small cell and 83% of small cell lung cancer patients had aneuploid DNA content; multiple aneuploid stem lines were present in 11% of patients. Comparisons with microscopic examination showed that aneuploid cells were detected in 122 of 167 clinical samples containing tumor cells and in 3 of 177 samples microscopically free of tumor. The high false-negative rate, shown to be due in large part to the presence of near-diploid tumor cells, makes single-parameter DNA analysis impractical for use in automated cytology. Short-term cultures of tumor cells, used to confirm that tumors had DNA content indistinguishable from diploid, demonstrated a single near-diploid peak on repeat DNA analysis with or without the addition of diploid lymphocytes and internal DNA standards. Chromosome banding studies showed clonal structural abnormalities with minimal numeric alterations. Survival of small cell lung cancer patients was similar for patients with near-diploid and aneuploid tumors. Cell cycle analysis could be performed in only a minority of samples, and there were no apparent differences in the proliferative fraction between lung cancer cell types. We conclude that flow cytometric DNA content analysis provides useful biological information and is a useful marker for following tumor cell cultures, but multiparameter analyses will be required for use in automated cytology and in cell kinetic studies.

A simple, rapid, high-resolution chromosome technic for lymphocytes

Phytohemagglutinin (PHA) stimulated lymphocytes were exposed to a hypotonic solution consisting of equal parts of 0.075 M 2-Mercaptoethanol and 0.075 M KCl, followed by addition of colcemid. The cells were fixed and washed in the usual manner. The slides then were subjected to trypsin-Giemsa banding. This method yields a high percentage of mitotic figures in prophase and prometaphase, ideal for high-resolution chromosome analysis.

Rh mosaicism and aberrant MNSs antigen expression in a patient with chronic myelogenous leukemia

This is, to our knowledge, the first report of combined Rh and MNSs antigen alteration in a leukemic patient. Red blood cells of a chronic myelogenous leukemia patient demonstrated mixed field reactions with anti-Rho (D) reagents in August 1980. Earlier tests indicated he was Rho (D) positive in 1967, but Rho (D) and Du negative from 1973 to 1980. Titration studies with anti-hr' (c) and anti-hr" (e) indicated depressed expression, and there was also very weak s expression. One hundred per cent of cells studied from 1967 to 1980 were Philadelphia chromosome (Ph1) positive. No abnormalities in chromosomes associated with the Rh or MNSs blood groups 1 and 4, respectively, were noted. Phenotypes from August 1980 through September 1981 revealed normalization of red blood cell antigen status with an increase of Rho (D) positive cells from 35% to 100%. Chromosomal studies in October, 1980 and June, 1981 revealed Ph1 mosaicism with 25 and 75% Ph1 negative cells, respectively. These findings suggest that normalization of previously altered red blood cell antigen expression may reflect resurgence of normal stem cell lines.

Fatal hypereosinophilia with chromosome 15q- in a patient with multiple primary and familial neoplasms

A man with large-cell carcinoma of the lung, cerebral meningioma, occult adenocarcinoma of the prostate, and follicular adenoma of the thyroid developed symptomatic, rapidly progressive hypereosinophilia with abnormalities of eosinophil ultrastructure and bone marrow karyotype (45,X,15q22-). Although the patient's eosinophilia defied strict classification as idiopathic hypereosinophilic syndrome (HES), simple tumor-associated eosinophilia, or eosinophilic leukemia, it appeared to be incited by the lung cancer and quickly acquired malignant independence. The family had an excess of prostate cancer and lymphoproliferative neoplasms.

Flowcytometric and cytogenetic analysis of human cultured cell lines derived from high- and low-grade astrocytomas

Five human cell lines cultured from high- and low-grade astrocytomas in cerebral hemisphere have been analyzed for DNA and protein distribution by flowcytometric (FCM) and correlated with cytogenetic profiles. Simultaneous calibration with chicken erythrocytes as a co-running standard provided an estimate of chromosomal number of predominate stem cells of each cell line by the ratio of the DNA content of the major peak (G1) to that of chicken erythrocyte (T/E ratio) of FCM. Various lines had different distributions of chromosomal number, ranging from near diploid to tetraploid. Each line had a stem-cell population and chromosomal markers indicative of clonal selection, but no common marker specific to astrocytomas. The histogram of DNA distribution obtained by FCM correlated well with the chromosomal distribution by cytogenetic analysis. In addition, simultaneous measurement of protein and DNA content in multidimensional FCM demonstrated a sigmoid configuration of the profiles, which indicated a gradual increase of protein content associated with an increase of chromosomal number or with progression of cell cycle. To avoid confusion of a bimodal chromosomal distribution with the G2/M phase of the cell cycle, and to determine chromosomal numbers associated with a DNA histogram, simultaneous cytogenetic and FCM study are required. More rapid than cytogenetic analysis, the T/E ratio allows estimation of chromosomal number of the stem-cell population associated with DNA histograms of cultured glioma-derived cell lines.

Clinical implications of cytogenetic studies in cutaneous T-cell lymphoma (CTCL)

Detailed cytogenetic studies were performed in 41 patients with cutaneous T-cell lymphoma (CTCL): four patients had limited plaques, 13 patients had generalized plaques, eight patients had cutaneous tumors, 16 patients had generalized erythroderma, and four additional patients, who had relatively benign chronic dermatosis, served as controls. Correlating the histologic and cytogenetic results in the various tissues, it was observed that 62% of the peripheral blood specimens were cytogenetically positive but only 49% were morphologically positive; in the lymph node the ratio was 80 versus 45%, and in the bone marrow, 6 versus 3%. These studies demonstrate that chromosome abnormalities are frequently detectable before morphologic changes become apparent. Chromosome banding preparations showed extensive and wide-ranging heteroploidy; the #1 chromosome was most frequently involved in structural abnormalities while chromosomes #11, 21, and 22 were most frequently involved in numerical abnormalities. These cytogenetic findings support the impression that CTCL is a disease whose various clinical manifestations represent a chronologic sequence, with the cytogenetic findings paralleling the clinical symptoms: patients with minimal chromosomal changes had the best survival and the more extensive the chromosome abnormalities, the more advanced the clinical disease. Clone formation was seen in eight patients and this phenomenon, along with hyperdiploidy and near-tetraploidy, was associated with a poor prognosis and short survival. We conclude that CTCL progresses from an early phase with extensive chromosomal abnormalities and lack of clone formation to a terminal phase with clone selection. Cytogenetic studies can, therefore, be of significant diagnostic and prognostic value in CTCL.