Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An ouabain- and thioguanine-resistant subline (TIKAUT) of spontaneous AKR lymphoma, TKA, was trisomic for chromosome 15 and contained a single 33 kb EcoRI fragment, containing the oncogene c-myc. The original TKA lymphoma and derived in vitro line contained the same 33 kb fragment, as well as a normal 22 kb fragment. It has been concluded that the original 15-trisomic TKA tumor has duplicated a 15-chromosome that contained the changed fragment, while maintaining the normal fragment as well. Subsequently, in the derived TIKAUT line, the changed chromosome duplicated again, giving rise to three copies, and the normal homologue was eliminated altogether. This confirms our earlier somatic hybrid study showing that the duplicated 15-chromosome of a T-cell leukemia confers an advantage on the cell that favors tumorigenicity, whereas the normal homologue exerts a counteracting influence. Therefore, in the course of tumor progression, the changed chromosome tends to be amplified, whereas its normal homologue tends to be eliminated.
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PMID:Triplication of one chromosome No. 15 with an altered c-myc containing EcoRI fragment and elimination of the normal homologue in a T-cell lymphoma line of AKR origin (TIKAUT). 632 25

Reactivity of B16 melanoma cell surface proteins with antisera to the major envelope glycoprotein, gp70, of murine leukemia viruses was assessed by radioimmunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Surface proteins from cultured monolayers of the B16 melanoma and variant lines B16-F1, B16-F1(1r6), B16-F10, and B16-F10(1r6), and from purified B16 melanoma tumor cells, contained three glycosylated components specifically reactive with gp70 antisera, with apparent molecular weights of 70,000, 80,000, and 85,000 (B16-gp70, B16-gp80, and B16-gp85). Antisera raised in syngeneic C57BL/6 mice by immunizing with X-irradiated B16, B16-F10, or B16-F10(1r6) cells immunoprecipitated only solubilized B16-gp70, B16-gp80, and B16-gp85. Absorption of mouse antiserum to B16-gp70/80/85 antigens with purified viruses from various sources indicated that antigens on all three molecules were related to endogenous AKR-type murine leukemia virus antigens. Mice hyperimmunized against melanoma cells were challenged subcutaneously with 4 X 10(4), 10(5), or 2.5 X 10(5) viable B16 or B16-F10 cells, inocula that were lethal and nonmetastatic in unimmunized mice. The lowest cell dose was rejected by 90% of immunized mice. Tumors grew in an average of 58% of immunized mice challenged with 10(5) cells, pulmonary metastases occurring in 61% of those mice. Inocula of 2.5 X 10(5) cells grew in all immunized mice, with a 60% incidence of metastasis. These studies indicate that host immunity to B16-gp70/80/85 antigens can either inhibit or stimulate B16 melanoma tumor progression.
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PMID:Multiple antigens related to the major envelope glycoprotein of murine leukemia virus expressed on B16 melanoma cells as targets of host immune response. 632 88

Cancer patients who were pregnant at the time of cancer diagnosis were identified by the National Cancer Registry of the German Democratic Republic for the years 1970 through 1979. A total of 355 such cases occurred in women aged 15-44, and during the same period 2, 103, 112 live births were registered. Rank by site in order of decreasing frequency was cervix, breast, ovary, lymphoma, melanoma, brain and leukemia. On the basis of general female population rates, 555.8 cases were expected, giving a significantly reduced observed to expected ratio (O/E) of 0.64. O/E ratios rose with age. The O/E for invasive carcinoma of the cervix was significantly elevated at 1.15; carcinoma in situ of the cervix occurred significantly less frequently than expected (O/E = 0.57). For breast, brain, melanoma and leukemia, significantly fewer cases were observed than expected. Explanations considered for the low number of pregnancy-associated incident cancer cases include underreporting of pregnancy-associated cancer, altered tumor progression in pregnancy or decreased fertility in women with early neoplastic disease.
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PMID:Pregnancy in association with a newly diagnosed cancer: a population-based epidemiologic assessment. 646 98

The effect of thymosin against tumor progression was examined in mice immunosuppressed by cytostatics or X-ray irradiation. When pretreated with cytostatic agents, such as 5-fluorouracil (5-FU) or BCNU, or by X-ray, and then inoculated with P388 or L1210 leukemias, mice died rapidly within a few days. In these systems, thymosin alpha 1 given concomitantly with the cytostatic agents or after X-irradiation prevented rapid death and extended survival, although the mice eventually died with leukemia like normal mice inoculated with cells of the same tumor. Rapid death in the 5-FU-treated mice was also prevented by adoptive transfer of spleen cells from the donor mice if these had been treated with 5-FU plus thymosin alpha 1, but not if they had received 5-FU alone. However, the restorative activity of the donor spleen cells was abrogated by treatment with anti-asialo GM1, but not by treatment with anti-Thy 1 or anti-mouse Ig serum, suggesting that the effector cells in the spleen are NK cells. In fact, thymosin alpha 1, when given concomitantly with 5-FU or after X-irradiation, maintained the NK activity of spleen, which was damaged by treatment with 5-FU or X-irradiation alone. The present study indicates that thymosin alpha 1 exerts a preventive activity against progression of leukemias at least in part through an effect on NK cells or their progenitor cells.
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PMID:Thymosin alpha 1 restores NK-cell activity and prevents tumor progression in mice immunosuppressed by cytostatics or X-rays. 655 15

The accumulation of amino acid and dipeptide derivatives of DNR has been studied in vitro on L1210 cells. Only Leu-DNR reaches accumulation levels close to DNR, while Val-DNR, Ile-DNR, and Leu-Leu-DNR reach intermediate values. Intracellular DNR was found when the L1210 cells were incubated in the presence of DNR, Leu-Leu-DNR, Leu-Ala-DNR, and Leu-DNR. The cytostatic activity of the derivatives in vitro on L1210 cells cannot be correlated with their uptake or conversion into DNR. At equitoxic doses given iv on the iv inoculated form of L1210 leukemia, all the derivatives are less active than DNR. When given iv on the sc inoculated L1210 leukemia, Leu-DNR, Ala-Leu-DNR and Leu-Leu-DNR are much more active than DNR with a striking increase in ILS and reduction of tumor progression. The superiority of those compounds could be due to their greater hydrophobicity and to their hydrolysis in situ by enzymes secreted by tumor cells or present on the tumor cells surface.
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PMID:Amino acid and dipeptide derivatives of daunorubicin. 2. Cellular pharmacology and antitumor activity on L1210 leukemic cells in vitro and in vivo. 745 66

About half of the patients with follicular lymphoma will develop an aggressive B cell lymphoma with morphological changes in growth pattern and cellular morphology. Changes of the immunophenotype, especially of the expression of immunoglobulin (Ig) have been documented less frequently. Multiple tumor samples of two patients with follicular lymphoma who developed tumor progression, were studied by Southern blot analysis for rearrangements of the Ig genes and the oncogenes BCL2 and MYC. In both patients, the general pattern of Ig gene rearrangements, especially of the Ig light-chain genes, and the structure of the t(14;18) breakpoint as assessed by the polymerase chain reaction (PRC) and fine restriction mapping, remained unaltered with time. However, both within the functional Ig heavy-chain allele and around the t(14;18) breakpoint, extensive secondary alterations took place. This indicates clonal evolution rather than the appearance of an independent lymphoma. In the first case with progression from follicular lymphoma to Burkitt's lymphoma 3 years after diagnosis, alterations were especially present 3' of the t(14;18) breakpoint. In the second patient with a change from follicular to diffuse centroblastic lymphoma 4 years after diagnosis, subsequent class switches from IgM to IgG and to defective IgH expression were accompanied by deletion of C mu sequences and a rearrangement of the MYC gene, respectively. Additionally, in both patients alterations in individual restriction sites occurred, which most likely were due to somatic mutations within both the functional IgH and translocated allele. Our data indicate that complex alterations of both the functional and non-functional IgH allele may accompany tumor progression and may erroneously suggest the appearance of independent clones by Southern blot analysis. It remains to be established whether these alterations are causative events or the consequence of genetic instability and clonal evolution.
Leukemia 1995 Oct
PMID:Histological conversion of follicular lymphoma with structural alterations of t(14;18) and immunoglobin genes. 756 20

Leukemias induced with the v-abl or BCR/ABL oncogene undergo a process of tumor progression which suggests that the ABL oncogene is required but not sufficient for full transformation. In order to identify cellular changes that correlate with progression to full transformation in v-abl transformed lymphoblasts Abelson virus (A-MuLV)-infected murine bone marrow was plated over a pre-established stromal feeder layer. Shortly after A-MuLV infection, transformed lymphoblasts were poorly oncogenic, but over time, progressed in a stepwide manner to a more oncogenic state. The transformants first acquired the ability to grow efficiently in agar, but only over the feeder layer. They next progressed to efficient feeder-independent growth in liquid culture, and then to efficient feeder-independent growth in soft agar. Cell lines that reached the advanced stage of feeder-independent agar growth showed increased detection by antiphosphotyrosine Western blot of the GAP-associated p62 phosphoprotein as well as of a 55 kDa phosphoprotein while detection of the P160 v-abl phosphoprotein remained constant throughout all stages of progression. Although the identity of the p55 phosphoprotein and the mechanism by which detection of p55 and p62 phosphoproteins change on the Western blots during tumor progression are unknown, the data demonstrate that these changes strongly correlate with the stage of progression of v-abl-transformed cells and raise the possibility that these changes may play a role in tumor progression in this model.
Leukemia 1995 Jan
PMID:Increased detection of specific tyrosine phosphoproteins correlates with tumor progression of Abelson virus-infected lymphocytes. 784 13

The effects of dietary restriction (DR) on spontaneous oncogenesis in male Fischer 344 rats were analyzed. Previously reported analyses of studies carried out in our laboratory demonstrated that DR reduces the incidence and delays the onset, but not the progression, of leukemia in male F344 rats. In this report, the influence of DR on pituitary tumors, adrenal pheochromocytoma, pancreatic islet cell tumors, and interstitial cell tumors of the testis was analyzed. DR reduced the relative incidence (relative onset rates) and delayed the onset of the four tumors. DR also retarded the progression (duration from onset to death) of pituitary tumors and pheochromocytoma. DR has delayed the onset of all tumors of the male F344 rat so far analyzed, but its effect on tumor progression appears to be lesion-dependent.
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PMID:Anti-tumor action of dietary restriction is lesion-dependent in male Fischer 344 rats. 787 82

Moloney murine leukemia virus (M-MuLV) induces promonocytic leukemias, called MML, in pristane-treated adult mice. These tumors invariably express fused gag-myb mRNA as a consequence of virus integration and activation of the c-myb locus. In the present study it was determined that while BALB/c and DBA/2N mice are highly susceptible, C57BL/6, C3H/He, STS/A, NFS, NIH/Swiss, SJL/J, and NZB mice are strongly resistant to tumor induction. Although C57BL/6 mice were resistant because they were unable to support early virus replication in hematopoietic tissue, NFS and C3H/He mice supported replication and were shown, using RT-PCR, to have cells in the bone marrow and spleen that expressed the aberrant, leukemia-related gag-myb mRNA. This provided evidence that early stages of leukemia were permitted to develop in these mice, but preneoplastic cells were unable to progress to the acute phase. Experiments in which MML was induced by M-MuLV plus pristane treatment in immunodeficient C3H/He nu/nu and sublethally irradiated C3H/He mice suggested that the immune response may play a role in eliminating preleukemic cells in immunocompetent C3H/He. Tumors from these mice had rearrangements at the c-myb locus and expressed gag-myb RNA. It was concluded that, at least in the case of C3H/He mice, resistance is not due to an inability of virus to activate c-myb or to a lack of other tumor promoting events. Rather, leukemia development appears to be restricted by an immune response, presumably T-cell mediated. Evidence is provided that non-H-2 MHC genes are required for resistance in both C57BL/6 and C3H/He mice and that resistance is dominant. This provides an animal model for the study of tumor progression as it relates to the immune response.
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PMID:Susceptibility and resistance to Moloney murine leukemia virus-induced promonocytic leukemia. 797 49

Initially, lymphoid cells transformed by v-abl or BCR/ABL oncogenes are poorly oncogenic but progress to full transformation over time. Although expression of the oncogene is necessary to initiate and maintain transformation, other molecular mechanisms are thought to be required for full transformation. To determine whether tumor progression in ABL oncogene-transformed lymphoid cells has a genetic basis, we examined whether progression of the malignant phenotype of transformed clones correlates with particular cytogenetic abnormalities. A modified in vitro bone marrow transformation model was used to obtain clonal Abelson murine leukemia virus-transformed B lymphoid cells that were poorly oncogenic. Multiple subclones were then derived from each clone and maintained over a marrow-derived stromal cell line for several weeks. Over time, clonally related Abelson murine leukemia virus-transformed subclones progressed asynchronously to full transformation. The data show that tumor progression can occur in the absence of detectable cytogenetic changes but, more importantly, that certain cytogenetic abnormalities appear reproducibly in highly malignant subclones. Therefore, three independent subclones showed deletion in a common region of chromosome 13. Other highly malignant cells carried a common breakpoint in the X chromosome, and, finally, two subclones carried an additional chromosome 5. These results are consistent with the hypothesis that ABL oncogenes are sufficient for the initial transformation of cells but that additional genetic events can drive oncogenic progression. These observations further suggest that diverse genetic mechanisms may be able to drive tumor progression in cells transformed with ABL oncogenes.
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PMID:Nonrandom cytogenetic changes accompany malignant progression in clonal lines abelson virus-infected lymphocytes. 799 46


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