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J Buer

Publications and source records attributed to J Buer.

53 records · Page 3Linked to original sources
PubMed1996

Peripheral blood tyrosinase messenger RNA detection and survival in malignant melanoma.

BACKGROUND: The most widely accepted criteria for the evaluation of prognosis of malignant melanoma are histopathologic and clinical presentation. No currently available laboratory tests provide additional prognostic information. It has recently been suggested that reverse transcription and polymerase chain reaction (RT-PCR)-based detection of tyrosinase messenger RNA (mRNA) in peripheral blood might be useful in the early detection of circulating tumor cells, since tyrosinase is thought to be a melanocyte-specific marker. PURPOSE: To further evaluate the clinical relevance of this potential marker, we examined peripheral blood samples from patients with malignant melanoma in different stages of disease for the presence of tyrosinase mRNA. METHODS: Total cellular RNA was extracted from heparinized peripheral blood cells from 64 patients with malignant melanoma, from five healthy control subjects, and from four patients with other cancers using the RNAzol A method. For analysis of tyrosinase mRNA, RT-PCR was performed as previously described by Smith et al.; the sensitivity of this assay was tested using RNA extracted from human melanoma cells (SK-mel 1 and SK-mel 3 cell lines) serially diluted with peripheral blood obtained from healthy control subjects. Two additional human melanoma cell lines (SK-mel 30 and RPMI-7951) served as positive controls for RT-PCR detection of tyrosinase mRNA. Overall patient survival curves were constructed using Kaplan-Meier estimates. RESULTS: Tyrosinase mRNA was detected by RT-PCR assay of all four of the established melanoma cell lines tested. Nine of the 64 patients with malignant melanoma were found to have detectable tyrosinase mRNA in their peripheral blood cells (tyrosinase-positive patients). The 16 patients with localized primary melanoma did not have detectable tyrosinase mRNA in their peripheral blood cells. Among the 48 patients with metastatic disease, all 27 patients who exhibited no evidence of disease progression were tyrosinase negative. Notably, all nine tyrosinase-positive patients had visceral metastases and were found to exhibit disease progression at the time of the sampling. Four of the nine tyrosinase-positive patients were also found to test negative at times without evidence of progressive disease; one patient became negative after achieving stable disease and three became positive for tyrosinase transcripts on disease progression. The probability of survival from time of sampling was significantly lower in the nine tyrosinase-positive patients when tested versus the 23 patients with comparable disease but without detectable tyrosinase mRNA (two-sided; P < or = .05). CONCLUSIONS: The results of this study demonstrate that the detection of tyrosinase mRNA in cells in the peripheral blood by RT-PCR may be a useful prognostic marker for predicting tumor progression and poor clinical outcome in patients with malignant melanoma.

Adult↗
PubMed1996

Linomide and interleukin-2 in patients with advanced renal cell carcinoma.

Quinoline-3-carboxamide (Linomide) is a novel, synthetic immunomodulator acting via immunologic and non-immunologic mechanisms. It has shown efficacy against various malignancies, experimental autoimmune encephalomyelitis, and septic shock in animal models and has been investigated for clinical use in minimal residual myeloid leukemia with promising results. Interleukin-2 has shown considerable efficacy in palliative anti-tumor-treatment of advanced renal cell cancer, revealing remission rates of up to 40% in combination therapy regimens. Linomide is reported to exhibit synergistic effects with interleukin-2. Here we report on a clinical phase I/II study examining tolerance and efficacy of a combination therapy schedule of SQ interleukin-2 and PO Linomide in advanced renal cell cancer. Seventeen patients received 10 IU/m2 interleukin-2 per week for 8 weeks, resting interleukin-2 for another 8 weeks. In week 5 they started 5 mg Linomide daily, continued with 10 mg from week 7 to 16. No objective remissions were observed. Among 15 patients evaluable for response, 10 (66.7%) were progredient during the study. Three patients died during the observation period, including two not evaluable for response. Median survival was 4.0 months, median progression-free survival 2.5 months with a Kaplan-Meier estimate of 3.63 months. Fever, reduced general condition, nausea/vomiting, dyspnea, anorexia, chills and hypotension were the most common side effects, reaching WHO grade 3 in 6 and grade 4 in 2 cases. In summary, Linomide in combination with interleukin-2 provides no advantages in efficacy or toxicity over other therapy regimens employing interleukin-2.

Adjuvants, Immunologic↗
PubMed1996

Cytogenetic studies in renal cell carcinoma patients receiving low-dose recombinant interleukin-2-based immunotherapy.

A variety of cytogenetic aberrations have been reported in sporadic and familial renal cell carcinoma. Rearrangements of the short arm of chromosome 3 (3p), trisomy 17, and nuclear hyperdiploidy have been reported to be common clonal chromosome changes. We analyzed a total of ten tumor-derived cell lines from patients who underwent nephrectomy for renal cell carcinoma employing conventional cytogenetics. All patients received an immunomodulatory therapy based on recombinant interleukin-2 (rIL-2). Tumor stage and grade, histo- and cytopathology, and patients' response to immunotherapy were assessed and correlated statistically to rearrangement of 3p, trisomy 17, and nuclear hyperdiploidy. Trisomy 17 as clonal aberration could be revealed only in papillary renal cell carcinoma, whereas tumors with compact or tubulopapillary growth pattern lacked this abnormality (p < 0.002). One of 3 patients with diploid or near-diploid karyotype (< or = 49 chromosomes) achieved a partial remission while two presented with stable disease after immunotherapy. In contrast, all 6 patients with tumor progression upon rIL-2-based immunotherapy revealed hyperdiploid (> 49 chromosomes) karyotypes. The correlation between hyperdiploidy and tumor progression was found to be statistically significant (p < 0.029). Interestingly, the only patient achieving an objective tumor remission after immunotherapy presented with a normal diploid karyotype. Our findings suggest tumor hyperdiploidy as an adverse prognostic factor in renal cell carcinoma patients receiving rIL-2-based immunotherapy.

Aged↗
PubMed1996

Exposure to vinblastine modulates beta 1 integrin expression and in vitro binding to extracellular matrix molecules in a human renal carcinoma cell line.

Solitary stroma-invading tumor cells expressing the ATP-binding cassette transporter P-glycoprotein have been reported to be associated with a significantly higher incidence of vessel invasion and lymph node metastases. In contrast to P-gp-mediated multidrug resistance (MDR) which has become well characterized over the last decade, little is known about further morphological and functional alterations in drug-resistant tumor cells. Binding of malignant cells to components of the extracellular matrix mediated by beta 1 integrins has been suggested to play a substantial role in the metastatic cascade. We studied alterations of beta 1 integrin expression and in vitro adhesiveness to extracellular matrix proteins of the human renal carcinoma line Caki-1 in comparison to the vinblastine resistant sublines Caki-1/V1 and Caki-1/V10 (cultured in the presence of 1 ng/ml and 10 ng/ml vinblastine, respectively). Both VLA-1 and VLA-2 receptors were acquired by the Caki-1/V10 subline, whereas untreated and Caki-1/VI cells lacked surface expression of these antigens. VLA-6 was found to be decreased in the vinblastine-resistant sublines. Attachment of drug-resistant Caki-1/V1 and Caki-1/V10 cells to collagen type I was significantly increased when compared to parental cells (p < or = 0.005). Significant differences in the attachment to type IV collagen were observed between Caki-1/V10 and untreated cells (p < or = 0.045). Both Caki-1/V1 and Caki-1/ V10 cells exhibited increased adhesion to fibronectin when compared to cells of the untreated line (p < or = 0.04). Whether an aberrant expression of beta 1 integrin receptors in resistant cells in combination with altered tumor cell adhesiveness is caused by MDR induction or whether it is an epiphenomenon of cytotoxic stress is unknown. Future studies will be needed to characterize the clinical relevance of MDR-associated changes in tumor cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

Biochemotherapy of advanced metastatic renal-cell carcinoma: results of the combination of interleukin-2, alpha-interferon, 5-fluorouracil, vinblastine, and 13-cis-retinoic acid.

We conducted a phase I/II clinical trial evaluating the sequential outpatient combination of S.C. recombinant human interleukin-2 (rIL-2; given at 10 MIU/m2 b.i.d. on days 3-5 weeks 1 and 4 and at 5 MIU/m2 on days 1, 3, and 5 of weeks 2 and 3), s.c. recombinant human alpha-interferon (rIFN-alpha; given at 6 MIU/m2 on day 1 of weeks 1 and 4 and on days 1, 3, and 5 of weeks 2 and 3 and at 9 MIU/m2 on days 1, 3, and 5 of weeks 5-8), i.v. bolus 5-fluorouracil (5-FU; given at 1,000 mg/m2 once weekly during weeks 5-8), and i.v. bolus vinblastine (given at 6 mg/m2 once weekly during weeks 5 and 8) in conjunction with p.o. 13-cis-retinoic acid (13-C-RA; given at 35 mg/m2 daily during weeks 1-8). Therapy was always given in the outpatient setting. Grade 3 constitutional symptoms (malaise, chills, fevers, anorexia) were observed in 4%-8% of treatment cycles and required a 50% reduction in the doses of rIL-2 and rIFN-alpha. None of the patients experienced major 5-FU-related toxicities such as severe diarrhea and/or stomatitis; up to 20% of patients developed vinblastine-associated peripheral polyneuropathy, which was reversible after the cessation of therapy. 13-cis-Retinoic acid produced no significant side effect; no toxic death occurred. Among 24 patients with progressive metastatic disease, there were 4 complete remissions (lung, lymph nodes) and 6 partial remissions (lung, pleura, liver, lymph nodes, and peritoneal carcinosis), for an overall objective response rate of 42% (95% confidence interval, 22%-63%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗
PubMed1995

Lymphocyte-conditioned medium in combination with interleukin-2 effectively induces antitumour autoimmunity by adoptive transfer of short activated killer (SHAK) cells.

In this study, effective antitumour immunity was transferred by autologous short activated killer (SHAK) cells induced over four hours with lymphocyte conditioned medium (LCM) and recombinant interleukin-2 (rIL-2). Among eight patients with progressive metastatic renal cell carcinoma refractory to standard therapy, there were six objective tumour responses to SHAKs. Progression-free survival ranged from 0 to 8+ months, and overall survival ranged from 2 to 14+ months, with a median of 9+ months. Systemic toxicity of SHAKs was limited to flulike symptoms. Patient SHAKs provided a tumour-specific immunity, both cellular and humoral (expression and secretion of secondary cytokines, including IL-2, GM-CSF, INF-gamma and TNF-alpha), far superior to rIL-2 activated killer cells.

Adoptive Transfer↗
PubMed1994

Cytokine-based biotherapy of gastrointestinal tumors.

Over the past 20 years the administration of cytokines has emerged as an important fourth modality for the treatment of human cancer. Advances in the field of therapy of gastrointestinal tumors have become a major focus of current research, given the lack of progress of conventional antineoplastic therapy in most of these tumors. Among the heterogeneous group of gastrointestinal malignancies, novel therapeutic strategies have been employed for each individual tumor type, and cytokines (interferon-alpha) have gained an established role in the treatment of advanced carcinoid tumors. Although our understanding of the mechanisms of biological response modification is still limited, further improvement in the management of gastrointestinal malignancies can be expected from multimodality therapy regimens employing cytokines in combination with other biological response modifiers, chemotherapeutic agents, active-specific immunotherapy, and immunotoxin- and radionuclide-conjugated monoclonal antibodies. A wide range of clinical and preclinical studies have been conducted in colorectal carcinoma; however, potential therapeutic benefit of cytokine-based biotherapy has not been fully defined. Therefore, largescale, i.e., multicenter, studies are required to quantify the potential therapeutic effects of cytokines in gastrointestinal tumors.

Clinical Trials as Topic↗
PubMed1994

In vivo time and dose dependency of interleukin-6 secretion in response to low-dose subcutaneous recombinant interleukin-2.

Serum concentrations of Interleukin-6 (IL-6) were determined in renal cell carcinoma patients treated with low-dose subcutaneous human recombinant interleukin-2 (rIL-2). In all patients, administration of rIL-2 resulted in a significant increase in IL-6 serum levels to peak values within 4 to 6 hours as measured by enzyme-linked immunosorbent assays (ELISA). Repetitive administration of rIL-2 induced significantly lower IL-6 serum peaks when compared to the initial administration of rIL-2. Cumulative IL-6 release, as expressed by the area under the concentration curve (AUC), appeared to be independent of rIL-2 dose distribution (10 million IU rIL-2/m2 versus 20 million IU rIL-2/m2), and IL-6 serum peaks showed no direct dose dependency. Prior rIL-2 immunotherapy had no measurable effect on rIL-2 induced IL-6 release, while steroids resulted in a significant suppression of secondary IL-6 did not correlate with response to rIL-2 therapy or survival of rIL-2 treated renal cell carcinoma patients.

Aged↗
PubMed1994

Detection of clonal T-cell populations in gastrointestinal lymphomas by analysis of cRNA conformational polymorphisms of rearranged T-cell-receptor-gamma genes.

Analysis of complementary RNA molecules of junctional regions of rearranged T-cell-receptor-gamma genes show a pattern of conformational polymorphisms which is specific for an individual lymphocytic clone. In a blinded study we analysed formalin-fixed, paraffin-embedded histological specimens from gastrointestinal lymphomas and control tissues (lymphomas: pleomorphic T-cell 10, anaplastic large cell [Ki1+] 9, centroblastic 5, immunocytoma 1, B-CLL 2, Hodgkin's 2, centroblastic-centrocytic 1, MALT [mucosa associated lymphoid tissue] 1, T-cell acute lymphoblastic leukaemia 1, non-lymphoid or polyclonal lymphoid tissues 5). Junctional regions of rearranged TCR-gamma genes were amplified by the polymerase chain reaction and the products were transcribed into cRNA. Conformational patterns of cRNA molecules were analysed by polyacrylamide gel electrophoresis. 13/20 T-lineage lymphomas and the T-cell acute lymphocytic leukaemia displayed a distinct cRNA band pattern, all B-lineage lymphomas and the non-lymphoid control tissues were negative. Only one case of nasopharyngeal (lymphoepithelial, Schmincke-Regaud) carcinoma showed a faint cRNA banding pattern. This novel and non-radioactive assay allows for the rapid detection and molecular characterization of clonal lymphoid populations in minute histological biopsy specimens.

Base Sequence↗
PubMed1994

Molecular detection and characterization of clonal cell populations in acute lymphocytic leukemia by analysis of conformational polymorphisms of cRNA molecules of rearranged T-cell-receptor-gamma and immunoglobulin heavy-chain genes.

Junctional regions of rearranged T-cell-receptor-gamma (TCR) and immunoglobulin heavy-chain (IgH) genes represent an idiotypic DNA sequence for an individual lymphocytic cell, and any clone or clonal disease developing from this cell. In this study, a novel methodology for detection and characterization of clone specific DNA sequences in patients with acute lymphocytic leukemia (ALL) was developed. Junctional regions of rearranged TCR-gamma IgH genes in specimens of bone marrow aspirates of patients with ALL (precursor-B-ALL ten, T-ALL two, null-ALL one; ALL not classified one), of a patient with lymphoid blast crisis of chronic myeloid leukemia, of a B-cell chronic lymphocytic leukemia, and in DNA from peripheral blood mononuclear cells of ten healthy volunteers were amplified by polymerase chain reaction (PCR). The PCR products were transcribed into complementary RNA (cRNA). Conformational polymorphisms of cRNA molecules were analyzed by non-denaturing polyacrylamide gel electrophoresis. A specific cRNA banding pattern for rearranged TCR-gamma or IgH genes was observed in all patients with lymphocytic leukemia. In contrast, analysis of DNA from healthy volunteers yielded a smear of confluent polymorphisms representing multiple different cRNA molecules. In two patients with precursor-B-ALL, cRNA banding patterns of junctional regions of rearranged TCR-gamma genes were analyzed in sequential bone marrow aspirates. The banding patterns disappeared after chemotherapy and achievement of blast clearance. This novel and rapid molecular assay offers several advantages as compared to Southern blot analyses and previous PCR based methodologies for the detection of clonal lymphocytic populations. With this methodology, studies on the clonal evolution of lymphoproliferative disorders (e.g. the prognostic significance of the emergence of additional clones) can be performed more easily than with any other traditional molecular method.

B-Lymphocytes↗
PubMed1993

Conformational polymorphisms of cRNA of T-cell-receptor genes as a clone-specific molecular marker for cutaneous lymphoma.

A novel molecular assay for the detection and characterization of monoclonal lymphoid populations in clinical specimens was developed. The assay is based on the principle that upon non-denaturing polyacrylamide gel electrophoresis RNA molecules separate into several metastable conformational forms. These conformational polymorphisms strictly depend on the nucleotide sequence of the individual molecule. Using DNA from formalin-fixed, paraffin-embedded tissue of patients with mycosis fungoides, highly variable junctional sequences of rearranged T-cell receptor gamma genes were amplified by polymerase chain reaction. Subsequently, the polymerase chain reactions products were transcribed into complementary RNA and analyzed by non-denaturing polyacrylamide gel electrophoresis. In clinical specimens with a monoclonal lymphoid population, a clone-specific pattern of bands was identified representing conformational polymorphisms of cRNA molecules of rearranged T-cell receptor gamma genes of the predominant lymphoid clone. Three biopsies from one patient taken from different sites of the body over 3 years yielded an identical pattern of bands. This methodology provides a novel and rapid tool for the molecular identification and characterization of clonal lymphoid populations in clinical specimens. It is likely to be of special value for studies on the clonal evolution of lymphoid disorders of the skin.

Base Sequence↗
PubMedDate not supplied

Immunocytochemical detection of P-glycoprotein: initial expression correlates with survival in renal cell carcinoma patients.

We evaluated 28 patients with advanced renal cell carcinoma for the initial expression of P-glycoprotein (MDR1 gene product) employing immunocytochemistry. Tumor specimens were obtained upon primary tumor nephrectomy. In all patients, progression-free survival time following nephrectomy was evaluated and correlated statistically with the staining results. Progression-free survival of patients with no or very few (< 1%) P-glycoprotein-positive tumor cells (n = 8, median survival 27.0 months) was significantly extended (p < 0.04) as compared to patients with 1% or more P-glycoprotein-positive tumor cells (n = 20, median survival 4.0 months). Correlations with histopathological tumor characteristics were insignificant. These results suggest a potential role for P-glycoprotein as a biologic parameter predictive of tumor progression in renal cell carcinoma patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Tumour microdissemination and survival in metastatic melanoma.

The value of tyrosinase messenger RNA (mRNA) detection by reverse-transcriptase polymerase chain reaction (RT-PCR) as a marker for circulating melanoma cells remains controversial. However, it has been suggested that detection of melanoma cell mRNA may be used to evaluate prognosis and disease progression in patients with advanced malignant melanoma. We used a highly sensitive tyrosinase RT-PCR detection assay to test peripheral blood specimens of 80 patients with metastatic malignant melanoma. Moreover, we developed a multiple marker RT-PCR assay detecting a variety of additional melanocyte/tumour specific markers addressing the potential heterogeneity of gene expression of circulating melanoma cells. Thus subgroups of 32 and 12 out of all the 80 patients were also analysed for multimarker gene expression in their peripheral blood and bone marrow specimens, respectively. Altogether, 15 out of 80 patients tested positive for one or more molecular markers with heterogeneous melanocyte/tumour gene expression patterns. All RT-PCR positive patients presented with progressive and widely disseminated disease. We concluded that the detection of melanoma cell mRNA occurs in a stage of massive tumour progression and may predict poor clinical outcome in advanced malignant melanoma patients (p < 0.001). In addition, the multiple marker RT-PCR analysis was more reliable and sensitive than a single molecular marker assay for the detection of melanoma cells.

Adult↗
PubMedDate not supplied

In vivo tumor necrosis factor-alpha as indicator of biologic and clinical response to low-dose SC recombinant interleukin 2.

The effect of low-dose human recombinant interleukin-2 (rIL-2) on the induction of secondary tumor necrosis factor-alpha (TNF-alpha) in vivo was studied in 16 patients with metastatic renal cell carcinoma. In all patients s.c. rIL-2 resulted in a significant increase in TNF-alpha serum levels within 4 to 8 hours, as determined by enzyme-linked immunosorbent assay (ELISA). TNF-alpha serum concentrations remained elevated up to 24 hours following single s.c. administration of rIL-2. Total secondary TNF-alpha release, as assessed by the area under the curve (AUC), appeared to be independent of dose distribution of rIL-2 (10 million IU rIL-2 q12 hours versus 20 million IU rIL-2 q24 hours). rIL-2 induced TNF-alpha release was significantly higher in patients who had received prior rIL-2 immunotherapy, while steroids resulted in a significant suppression of TNF-alpha release. Secondary TNF-alpha release was statistically associated with progression-free survival of renal cell carcinoma patients and may be a prognostic factor in patients receiving rIL-2.

Adult↗