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J M Trujillo

Publications and source records attributed to J M Trujillo.

At least 37 records · Page 2Linked to original sources
PubMed1992

The t(15;17) breakpoint in acute promyelocytic leukemia cluster within two different sites of the myl gene: targets for the detection of minimal residual disease by the polymerase chain reaction.

The retinoic acid receptor alpha (RAR alpha) and the myl gene are involved in the translocation breakpoint t(15;17)(q22;q21) in acute promyelocytic leukemia (APL). The majority of the breakpoint sites have been mapped within the second intron of the RAR alpha gene; however, the breakpoint sites on the myl gene are variable. Using primer sets derived from exon 2 or exon 3 of the RAR alpha gene and a primer derived from the myl cDNA, we were able to amplify the breakpoint sites of the fusion transcripts of all six APL RNA samples by the reverse transcriptase-polymerase chain reaction (RT-PCR). A DNA fragment of 290 bp (breakpoint A) was amplified using RNA samples from three patients, whereas two DNA fragments of 630 and 774 bp (breakpoint B) were amplified using RNA samples from the other three APL patients. DNA sequence analysis of the amplified fragments suggests that the APL breakpoints clustered within two different introns of the myl gene. Northern blot analysis demonstrated that fusion transcripts RAR alpha/myl and myl/RAR alpha of varying sizes were detected in patients with different breakpoint sites on the myl gene. In addition, we analyzed five APL samples in complete remission and detected t(15;17)-positive cells. We conclude that the t(15;17) breakpoints in APL can be amplified by PCR using a single primer set and that minimal residual disease can be demonstrated in APL using RT-PCR.

Base Sequence↗
PubMed1992

Acute-phase proteins in patients with head and neck cancer treated with interleukin 2/interferon alfa.

Circulating acute-phase proteins may mediate adverse reactions in patients receiving biologic response modifiers, including inhibition of immune responsiveness and clinical toxic effects. Nine patients with unresectable head and neck squamous cell carcinoma were prospectively examined for levels of acute-phase proteins during interleukin 2/interferon alfa immunotherapy and for clinical toxic effects. Simultaneous determination of the in vitro immunomodulatory capacity of autologous serum on the induction of lymphokine-activated killer cells was assessed in 4-hour chromium release assays. Of the seven acute-phase proteins analyzed, haptoglobin and C-reactive protein levels were elevated before therapy was started. Toxic events leading to cessation of interleukin 2/interferon alfa therapy had a high correlation with elevated C-reactive protein and lowered C3 component of complement levels. No relationship was noted between serum levels of acute-phase proteins and induction inhibition of lymphokine-activated killer cell cytotoxicity. The role of C-reactive protein and complement degradation products in mediating interleukin 2/interferon alfa toxicity requires further investigation.

Acute-Phase Proteins↗
PubMed1992

PCR amplification of chromosome-specific DNA isolated from flow cytometry-sorted chromosomes.

We have established a method for amplifying and obtaining large quantities of chromosome-specific DNA by linker/adaptor ligation and polymerase chain reaction (PCR). Small quantities of DNA isolated from flow cytometry-sorted chromosomes 17 and 21 were digested with MboI, ligated to a linker/adaptor, and then subjected to 35 cycles of PCR. Using this procedure, 20 micrograms of chromosome-specific DNA can be obtained. Southern blot analysis using several DNA probes previously localized to chromosomes 17 and 21 indicated that these gene sequences were present in the amplified chromosome-specific DNA. A small quantity of the chromosome-specific DNA obtained from the first round of PCR amplification was used to amplify DNA for a second, third, and fourth round of PCR (30 cycles), and specific DNA sequences were still detectable. Fluorescence in situ hybridization using these chromosome-specific DNA probes clearly indicated the hybridization signals to the designated chromosomes. We showed that PCR-amplified chromosome 17-specific DNA can be used to detect nonrandom chromosomal translocation of t(15;17) in acute promyelocytic leukemia by fluorescence in situ hybridization.

Base Sequence↗
PubMed1992

Seroprevalence and cofactors of HTLV-I infection in Tumaco, Colombia.

This study presents an analysis of the factors associated with HTLV-I seroprevalence in the endemic area of Tumaco, Colombia. During June to August 1988, 1,077 individuals were selected at random from a population of 45,594. The overall prevalence rate of HTLV-I antibodies was 2.8%. Among females prevalence was significantly higher (p less than 0.02) than among males. Rates increased substantially with age. HTLV-I prevalence among individuals with history of use of intravenous medications was significantly higher (p less than 0.001) than in those without such history. Logistic regression analysis included age in years, indicators for male gender, and for i.v. injections, and their interactions. Age was very strongly associated to HTLV-I infection among females. At early ages prevalence was not different between sexes, but females presented a significantly higher rate than males after age 42. History of i.v. administered medications was very strongly associated in the univariate analysis and, although significance was borderline in the multivariate analysis, it had the effect of doubling the odds of HTLV-I infection.

Adolescent↗
PubMed1992

Characterization of a fusion cDNA (RARA/myl) transcribed from the t(15;17) translocation breakpoint in acute promyelocytic leukemia.

A nonrandom chromosomal translocation breakpoint, t(15;17)(q22;q21), is found in almost all patients with acute promyelocytic leukemia (APL). Most of these breakpoints occur within the second intron of the retinoic acid receptor-alpha (RARA) gene. We screened a cDNA library of APL and have identified and sequenced a cDNA transcribed from the t(15;17) translocation breakpoint. The 5' end of cDNA p1715 consists of 503 bp of the RARA exon II sequence. A 1.76-kb cDNA without homology to any known gene available in GenBank was found truncated downstream. This cDNA sequence was assigned to chromosome 15 by dot blot hybridization of the flow cytometry-sorted chromosomes. We designate this fusion cDNA RARA/myl, which is different from myl/RARA reported by de The et al. (H. de The, C. Chomienne, M. Lanotte, L. Degos, and A. Dejean, Nature (London) 347:558-561, 1990). This result demonstrates that the two different types of hybrid mRNA can be transcribed from this breakpoint. We screened a non-APL cDNA library and identified a 2.8-kb myl cDNA. This cDNA is able to encode a polypeptide with a molecular weight of 78,450. Alternative splicing of the myl gene which resulted in myl proteins with different C terminals was found. Southern blot analysis of the genomic DNA isolated from 17 APL patients by using the myl DNA probe demonstrated that the myl gene in 12 samples was rearranged. Northern (RNA) blot analysis of RARA gene expression in two APL RNA samples showed abnormal mRNA species of 4.2 and 3.2 kb in one patient and of 4.8 and 3.8 kb in another patient; these were in addition to the normal mRNA species of 3.7 and 2.7-kb. The myl DNA probe detected a 2.6-kb abnormal mRNA in addition to the normal mRNA species of 3.2, 4.2, and 5.5 kb. Using the polymerase chain reaction, we demonstrated that both RARA/myl and myl/RARA were coexpressed in samples from three different APL patients. From this study, we conclude that the t(15;17) translocation breakpoint results in the transcription of two different fusion transcripts which are expected to be translated into fusion proteins.

Amino Acid Sequence↗
PubMed1992

AML-associated cytogenetic abnormalities (inv (16), del (16), t(8;21)) in patients with myelodysplastic syndromes.

Evidence suggests that prognosis in patients with myelodysplastic syndromes (MDS) or acute myelogenous leukemia (AML) depends more on karyotype than on formal classification as either MDS or AML according to the French-American-British (FAB) system. We provide further evidence of overlap between these two entities, reporting 4 patients who presented with either inv(16) (p13q22), del(16) (q22), or t(8;21) despite an FAB diagnosis of MDS rather than the diagnosis of AML with which these abnormalities are generally associated. In 3 patients, disease was relatively long-standing (3-10 months) prior to diagnosis, suggesting that the association between MDS and these cytogenetic abnormalities may not merely reflect a transient phenomenon. Two patients with inv(16) and the MDS subtype refractory anemia with excess blasts in transformation (RAEB-t) received AML-type chemotherapy as did a patient with t(8;21) and RAEB-t. All entered CR paralleling the high CR rate seen in patients with AML and these abnormalities. Our data support the concept that MDS and AML may be different manifestations of the same disease.

Adolescent↗
PubMed1992

Cytogenetics for detection of minimal residual disease in acute myeloblastic leukemia.

Bone marrow samples collected from acute myeloblastic leukemia (AML) patients in complete clinical and hematological remission were studied for the persistence of cytogenetic abnormalities. AML patients from the three favorable cytogenetic categories [inv 16, t(8;21) and t(15;17)] and patients from the unfavorable cytogenetic categories (+8, -5, -7 and Philadelphia-positive) were studied. Seventy-one patients had evaluable metaphase spreads in remission marrows and 20 (28%) had one or more abnormal metaphases identical to that present in the pretreatment marrow. All 20 of these patients relapsed within 78 weeks, thus there were no false positive studies. Fifty-one patients had only diploid metaphases in their complete remission marrow, 25 relapsed, and 21 remained in continuous complete remission. Thus there was a 49% false negative rate of this study. These data indicate that the failure to detect residual chromosomally abnormal cells in the bone marrow does not guarantee continuous complete remission. Cytogenetic study was most useful in the favorable cytogenetic groups and least useful in the unfavorable groups. The persistence of normal metaphases in pretreatment marrows did not affect outcome or risk of recurrence. Twenty-five of 34 evaluable patients who relapsed after remission had either the identical cytogenetic abnormality present in the pretreatment marrow or showed the identical abnormality with additional chromosomal changes. Thus study indicates that cytogenetic examinations of complete remission bone marrow samples in patients with AML provides an objective method for detecting residual leukemia, and identifies patients with a potential for prolonged disease-free survival.

Bone Marrow↗
PubMed1991

Interferon-alpha produces sustained cytogenetic responses in chronic myelogenous leukemia. Philadelphia chromosome-positive patients.

OBJECTIVES: To evaluate the frequency and the course of complete cytogenetic responses in interferon-alpha (IFN-alpha)-treated patients with chronic myelogenous leukemia. DESIGN: Two prospective trials in consecutive patients. SETTING: A major tertiary cancer center. PATIENTS: Ninety-six consecutive patients with chronic myelogenous leukemia with disease duration of less than 1 year. INTERVENTION: Patients received partially pure IFN-alpha intramuscularly, from 3 to 9 million U/d (51 patients) or recombinant IFN-alpha 2a (Roferon, Hoffmann-LaRoche, Inc., Nutley, New Jersey), 5 million U/m2 body surface area daily (45 patients). MEASUREMENTS: Hematologic and cytogenetic tests were administered. MAIN RESULTS: Seventy of the patients (73%) achieved hematologic remission (95% CI, 63% to 81%), and 18 (19%) had complete suppression of the Philadelphia chromosome on at least one cytogenetic test. A complete cytogenetic response was induced in 7 of 51 or 14% (CI, 6% to 26%) of the patients treated with the partially pure IFN-alpha and in 11 of 45 or 24% (CI, 13% to 40%) of the patients treated with recombinant IFN-alpha 2a. The difference in complete cytogenetic response between the two groups was 10.7% (CI, - 5% to 26%; P greater than 0.2). Eleven patients had durable, ongoing, complete cytogenetic responses from 6 to more than 45 months (median, more than 30 months). CONCLUSION: This study was the first to show sustained, complete cytogenetic responses in a subset of patients with chronic myelogenous leukemia treated with single-agent therapy. The nature of this remission, that is, whether it depends on continuous therapy, requires further study.

Adult↗
PubMed1991

Purification of a new peroxidase catalysing the formation of lignan-type compounds.

A novel peroxidase that catalyses the dimerization of ferulic acid or caffeic acid via oxidative coupling and formation of beta beta'-linkage to the lignan-type compounds 8,8'-bis(caffeic acid) or 8,8'-bis(ferulic acid) respectively was purified from the leaves of Bupleurum salicifolium. The enzyme, for which the name caffeate peroxidase is proposed, was purified 2700-fold. It is a glycoprotein and has an Mr of 38,000 as determined by gel filtration and SDS/PAGE. The Km values for ferulic acid and caffeic acid were 0.24 mM and for H2O2 0.04 mM with caffeic acid and 0.48 mM with ferulic acid. The purified peroxidase does not exhibit activity on other phenylpropanoids tested and has no detectable phenol oxidase or NADPH oxidase activity. The caffeate peroxidase could be involved in the biosynthesis of lignans.

Catalysis↗
PubMed1991

Growth modulation by epidermal growth factor (EGF) in human colonic carcinoma cells: constitutive expression of the human EGF gene.

The functional role of epidermal growth factor (EGF) in epithelium-derived human colonic carcinoma cells was investigated by transfection with plasmid pUCDS3, which contained synthetic human EGF encoding sequences, into two human colonic carcinoma cell types with dissimilar phenotypic properties: the moderately differentiated and growth factor-responsive Moser and the highly metastatic KM12SM cells. The Moser cells exhibited a proliferative response to treatment with exogenous EGF, while the KM12SM cells did not. The constitutive expression of the human EGF gene in these colonic carcinoma cell types resulted in elevated expression of EGF mRNA, with concurrent production and secretion of a large amount of EGF, and downmodulation of transforming growth factor-alpha (TGF-alpha) secretion. Growth stimulation and down-modulation of both high and low affinity EGF receptors were observed in the EGF-transfected Moser clones. Results of experiments using anti-EGF and anti-EGF-receptor antibody to block the proliferation of EGF-transfected Moser clones suggested that autocrine stimulatory mechanisms involving both EGF and TGF-alpha were operative in these cells. By comparison, a growth-inhibitory effect, with no apparent EGF receptor modulation, was observed in the EGF-transfected KM12SM clones. Both the parental and EGF-transfected KM12SM clones possessed fewer EGF receptors than the Moser cells, and anti-EGF or anti-EGF-receptor antibody did not affect the cells' growth properties. These results suggested that the mechanisms of growth inhibition in the EGF-transfected KM12SM clones were non-autocrine or intracellular in nature. Thus, constitutive expression of the human EGF gene in two phenotypically different, epithelium-derived human colonic carcinoma cells resulted in divergent altered growth characteristics.

Cell Division↗
PubMed1991

8;20 chromosomal translocation in a case of acute leukemia. Cytogenetic, immunophenotypic, ultrastructural, and molecular characteristics.

An 8;20 chromosomal translocation was observed in the leukemia cells of a 3-year-old girl. To our knowledge, this is the first report of this translocation in de novo acute leukemia. This chromosomal defect was present in the leukemia cells at diagnosis and also at relapse, but remission bone marrow cells had the 46,XX karyotype. By morphologic and cytochemical criteria the leukemia was myeloid but these features were more lymphoid when the leukemia recurred. However, the immunophenotype was consistent with myeloid leukemia and did not change at relapse. No evidence for either immunoglobulin or TCR gene rearrangement was observed.

Biomarkers, Tumor↗
PubMed1991

Serum lactate dehydrogenase-3 isoenzyme in chronic granulocytic leukemia.

Abnormal levels of serum lactate dehydrogenase-3 (LD-3) activity were observed in 92% of patients (35 of 38) with active chronic granulocytic leukemia (CGL), in 40% of patients (4 of 10) in partial remission, and in 13% of patients (1 of 8) in complete remission. In evaluating the electrophoretic LD isoenzyme patterns of these patients, three criteria were used. In criterion-1 elevations, the LD-3/total LD ratio, expressed as a fraction of serum total LD, and LD-3 value, expressed in absolute units, were greater than the upper limit of the reference range. In criterion-2 elevations, only the LD-3/total LD ratio was greater than the upper limit of the reference range. In criterion-3 elevations, only the absolute LD-3 activity exceeded the upper limit of the reference range, and these specimens showed isomorphic elevation of all five LD isoenzymes. Use of the last of these criteria increased the clinical sensitivity of serum LD-3 elevations in active CGL from 82% to 92%. The mean serum LD-3 absolute value and serum total LD activity usually showed statistically significant differences (P less than 0.05) among patients with active CGL, those in partial remission, and those in complete remission, but did not distinguish between subgroups of individuals with active CGL. Elevation of the serum LD-5/total LD ratio in 16 of 58 patients was due to hepatic injury or methodologic imprecision, showing analytically insignificant, borderline abnormalities in all cases of active CGL. In 10 of 62 patients in complete remission or partial remission, however, such elevation was unexplained. Our results indicate that the evaluation of serum LD-3 values in both absolute and relative terms slightly increases the clinical sensitivity of LD-3, and, therefore, suggest that LD-3 might be a useful marker for CGL.

Biomarkers, Tumor↗
PubMed1991

Immunomodulation of the induction phase of lymphokine-activated killer activity by acute phase proteins.

Effective treatment of head and neck cancer with biologic response modifiers may be benefitted by an understanding of in vivo factors capable of modulating the lymphokine-activated killer (LAK) cell phenomenon. Eighteen patients with squamous cell carcinoma of the head and neck were studied. Killer cells from each patient, activated by recombinant interleukin-2 (10 U/ml), were induced in either complete medium alone or complete medium plus 10% autologous serum solution and analyzed. Cytotoxicity against both K562 and squamous cell carcinoma (MDA686-Ln) cell lines was determined by use of standard chromium-release assays. The immunomodulatory capacity of serum was correlated with levels of various acute phase proteins. Autologous serum significantly inhibited the induction phase of the LAK phenomenon in 61% of patients and stimulated it in 22%. No patients with early stage I or II disease had significant inhibition of induction. No direct correlation between inhibition and serum acute phase protein levels were seen. An inverse relationship was seen between the C3 component of complement and induction inhibition (r = -0.6). These findings suggest that advances of in vivo immunomodulatory therapy will require elucidation of mechanisms of serologic inhibition of the induction phase of the LAK phenomenon. Such studies may lead to serologic modification to enhance treatment efficacy of biologic response modifiers.

Acute-Phase Proteins↗
PubMed1991

Rearrangement of the retinoic acid receptor gene in acute promyelocytic leukemia.

The retinoic acid receptor-alpha (RAR-alpha) gene was previously localized to chromosome 17q21, a region close to the t(15;17) (q22;q21) abnormality in acute promyelocytic leukemia (APL). We used the RAR-alpha gene as a probe and found that eight of nine APL patient samples with t(15;17) (q22;q21) showed rearranged bands. A tenth APL patient was diploid and demonstrated no rearrangement. One patient who had rearrangement as an acute leukemia did not have rearrangement in remission. The results obtained from intron/exon mapping of the RAR-alpha gene demonstrated that breakpoints of seven of the eight patients occurred within intron 1. Northern blot analysis of leukemic samples indicated the expression of two RAR-alpha mRNA of 2.7 and 3.7 kb. However, two additional mRNA of 4.1 and 3.2 kb were found in an APL patient. We conclude that the RAR-alpha gene is directly involved in the t(15;17) translocation in APL and may transcribe aberrant messages.

Blotting, Northern↗
PubMed1991

Down regulation of myeloperoxidase gene associated with specific nuclease hypersensitive sites during TPA induced differentiation of HL-60.

The level of myeloperoxidase (MPO) mRNA is reduced significantly after HL-60 induced differentiation with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). We examined the chromatin structural changes of the MPO gene during TPA induction. Before TPA induction about nine DNase I hypersensitive sites (HS) were found on the 5' upstream and at various intron regions of the MPO gene. A new HS was found on intron 8 within 4 h of induction; its appearance preceded down regulation of the MPO gene. At the same time DNase I HS found in 0.3 and 1-1.5 kb upstream of the MPO CAP site, were significantly reduced or disappeared after TPA induction. These chromatin structural changes could be closely linked to the mechanism which regulates the MPO gene expression.

Blotting, Southern↗
PubMed1990

RAS mutations are rare events in Philadelphia chromosome-negative/bcr gene rearrangement-negative chronic myelogenous leukemia, but are prevalent in chronic myelomonocytic leukemia.

Previous reports have indicated that mutations of the RAS oncogenes are not associated with the chronic phase of Philadelphia chromosome-positive chronic myelogenous leukemia (Ph1+ CML). However, further studies were needed to determine their association with Ph1- CML and chronic myelomonocytic leukemia (CMML). Therefore, 6 patients with Ph1- CML who were also negative for BCR rearrangements (Ph1-/BCR- CML) and 30 patients with CMML were analyzed for the presence of RAS oncogene point mutations to determine the similarities of these diseases at the molecular level. The assay used the polymerase chain reaction for amplification of the target RAS sequences and panels of specific synthetic oligonucleotide probes for hybridization to wild type and/or mutated sequences. None of the six Ph1-/BCR- CML patients had mutations in the RAS oncogenes, while 17 of 30 (57%) of the CMML patients had RAS oncogene mutations. Eighty percent of the mutations involved substitution of aspartic acid for glycine (G----A) in the 12th or 13th codons of N-ras or K-ras. Furthermore, although not statistically significant, survival studies raise the possibility of shortened survival in patients with RAS oncogene point mutations, with the average survival being 33 months for Ph1-/BCR- CML, 35 months for CMML without point mutations, and 11 months for CMML with RAS mutations. Thus, RAS mutations appear to be associated with CMML and not Ph1-/BCR- chronic phase CML, there is a high propensity for the K-ras or N-ras mutations to involve an G----A substitution in the 12th or 13th codons, and RAS mutations in CMML may relate to prognosis and require further studies.

Gene Rearrangement↗
PubMed1990

Chromosomal breakpoints within the first intron of the ABL gene are nonrandom in patients with chronic myelogenous leukemia.

Bone marrow cells from 37 patients with chronic myelogenous leukemia (CML), who had the characteristic Philadelphia chromosome in their leukemic cells, were examined for ABL gene rearrangement by pulsed-field gel electrophoresis. By using several probes from the ABL gene, we found that in 33 of 37 (89%) patients studied, the translocation breakpoints in ABL fell within the 175-kilobase (kb) intron between exons 1b and 1a. Furthermore, breakpoints in this intron clustered in three regions, approximately 30 +/- 5, 100 +/- 13, and 135 +/- 8 kb downstream from exon 1b. These findings suggest that there may be specific sequences in this intron that facilitate the processes of chromosomal translocation.

Blotting, Southern↗