Biomedical subjects

Guido Bisping

Publications and source records attributed to Guido Bisping.

7 recordsLinked to original sources

PubMed2006

Proteasome inhibition in multiple myeloma.

The ubiquitin-proteasome pathway is the major cellular degradative system for various proteins critical for proliferation, survival and homing of myeloma cells. Bortezomib is the first specific and reversible proteasome inhibitor for clinical application in humans. Phase I studies have defined the maximum tolerated dose and suggested activity against multiple myeloma. From single agent phase II studies, a rate of at least partial responses ranging from 27% for relapsed and refractory to 38% for second-line patients was derived. In comparison with pulsed dexamethasone, bortezomib enabled a higher response rate, a longer time to myeloma progression and a longer survival for patients after one to three prior lines of therapy. Preclinical and clinical phase I studies as well as initial phase II studies combining bortezomib with conventional chemotherapy or thalidomide support the assumption that bortezomib sensitizes myeloma cells to these drugs resulting in additive or synergistic activity.

Antineoplastic Agents↗

PubMed2006

Growth inhibition and induction of apoptosis in acute myeloid leukemia cells by new indolinone derivatives targeting fibroblast growth factor, platelet-derived growth factor, and vascular endothelial growth factor receptors.

In acute myeloid leukemia (AML), receptor tyrosine kinase ligands promote growth and survival and contribute to AML-associated marrow neoangiogenesis. We have tested simultaneous inhibition of vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptor signaling by novel indolinone derivatives using 14 myeloid, including 11 human leukemic, cell lines. Compounds inhibited colony formation of all cell lines in a dose-dependent fashion. Inhibitory concentrations for 50% of the colony formation/survival (IC50) for BIBF1000 were <100 nmol/L for 3 of 11, <or=500 nmol/L for 6 of 11, and <1,000 nmol/L for 10 of 11 leukemic cell lines, with one cell line being resistant in the dose range <1,000 nmol/L. BIBF1120 was less effective with 4 of 11 leukemic cell lines being resistant within the dose range <1,000 nmol/L. Testing of myeloid 32D cells transfected with empty vector, wild-type Flt3, or Flt3 carrying an internal tandem duplication mutation revealed higher resistance for the internal tandem duplication mutant. These effects of the compounds were associated with inhibition of tyrosine phosphorylation and the mitogen-activated protein kinase pathway. Furthermore, both compounds induced apoptosis in the sensitive cell lines. In Mono-Mac1 cells, the compounds had a direct proapoptotic effect that was increasing the proapoptotic effect of 1-beta-D-arabinofuranosylcytosine. The data provide a rationale for clinical evaluation of these tyrosine kinase inhibitors in AML.

Acute Disease↗

PubMed2005

Targeting receptor kinases by a novel indolinone derivative in multiple myeloma: abrogation of stroma-derived interleukin-6 secretion and induction of apoptosis in cytogenetically defined subgroups.

In multiple myeloma (MM), both vascular endothelial (VEGF) and basic fibroblast growth factor (bFGF) promote tumor growth and survival. We have used the novel indolinone BIBF 1000 to study effects of simultaneous inhibition of VEGF, FGF and transforming growth factor-beta on MM cells and their interactions with bone marrow stroma cells (BMSCs). Both, in the absence and presence of myeloma-stroma cell contacts, BIBF 1000 abrogated BMSC-derived secretion of interleukin-6 (IL-6). In addition, BIBF 1000 directly induced apoptosis in t(4;14)-positive cell lines as well as in CD138+ marrow cells from patients with t(4;14) myeloma. To a similar extent, BIBF 1000 induced apoptosis in MM.1S and MM.1R cells carrying the translocation t(14;16). In case of MM.1S and other dexamethasone-sensitive t(14;16) cell lines, BIBF 1000 and dexamethasone had additive proapoptotic effects. Induction of apoptosis by BIBF 1000 was associated with inhibition of the mitogen-activated protein kinases (MAPK) pathway in t(4;14) and inhibition of the phosphatidyl-inositol-3 kinase/AKT pathway in t(14;16) cells. Apoptotic effects did not occur in t(4;14)-or t(14;16)-positive MM cells carrying n- or k-Ras mutations. The data provide the rationale for clinical evaluation of this class of targeted kinase inhibitors in MM with focus on defined cytogenetic subgroups.

Anti-Inflammatory Agents↗

PubMed2005

Bortezomib in combination with dexamethasone for relapsed multiple myeloma.

Fifteen patients with advanced multiple myeloma were scheduled to receive bortezomib 1.3 mg/m2 IV days 1, 4, 8, and 11 every 3 weeks for eight cycles in combination with dexamethasone. One patient (7%) achieved a complete response, 10 (67%) a partial response, and one (7%) a minor response (MR) resulting in an overall response rate (> or = MR) of 80% (9/9 with > or = 2nd untreated and 3/6 with refractory relapse). Responses occurred after a median of 3 weeks and were independent of conventional prognostic parameters including deletion of chromosome 13. Adverse events, mainly myelosuppression, neuropathy and fatigue, were manageable.

Adolescent↗

PubMed2004

Graft-versus-host disease after allogeneic hematopoietic stem cell transplantation induces a CD8+ T cell-mediated graft-versus-tumor effect that is independent of the recognition of alloantigenic tumor targets.

Cure of hematologic malignancies after allogeneic hematopoietic stem cell transplantation is partially attributable to immunocellular antitumor reactions termed graft-versus-tumor (GvT) effect. GvT effects are heterogeneous with respect to effector cell populations, target antigens, and their interrelation with graft-versus-host disease (GvHD). In the present study, allogeneic parent-into-F1 murine transplantation models (BALB/c or C57BL/6 --> [C57BL/6 x BALB/c]F1) with different tumors derived from either parental strain were used to evaluate tumor-specific GvT effects. Compared with syngeneic F1-into-F1 controls, significant CD8+ T cell-mediated GvT effects occurred in both allogeneic transplantation models, even in the absence of histoincompatibilities between donor cells and host tumor. Identical genetic background of donor and tumor precluded allorecognition of tumor cells, indicating that tumor-associated antigens (TAAs) were targeted. With allowance made for selective major histocompatibility complex (MHC) disparities between donor cells and normal host tissue, GvHD was identified as a driving force for TAA-specific GvT effects. Adoptive transfer of the effector cells into secondary tumor-bearing recipients confirmed sustained antitumor activity and specificity of the T-cell response. The results provide experimental proof of a donor CD8+ T cell-mediated TAA-specific antitumor response in vivo that is driven by GvHD. It may represent one of the mechanisms contributing to GvT effects observed in allogeneic transplant recipients.

Adoptive Transfer↗

PubMed2003

Hyperfractionated cyclophosphamide in combination with pulsed dexamethasone and thalidomide (HyperCDT) in primary refractory or relapsed multiple myeloma.

Sixty patients with advanced multiple myeloma received 2-6 monthly treatment courses combining hyperfractionated cyclophosphamide (300 mg/m2 i.v. over 3 h q 12 h x 6, d 1-3) with pulsed dexamethasone (20 mg/m2/d p.o., d 1-4, 9-12, 17-20) and once daily thalidomide at individually escalating doses (100-400 mg/d) depending on tolerability (HyperCDT). Responding patients were maintained on daily thalidomide and monthly dexamethasone pulses. Complete, partial and minor response rates were 4%, 68% and 12% respectively; overall response rate was 84% (efficacy analysis). Median event-free and overall survival was 11 and 19 months respectively. During at least one treatment cycle, 67% of patients experienced grade 4 neutropenia resulting in 17% grade 3 and 9% grade 4 infections. Side-effects, presumably related to thalidomide, included neuropathy (40% grade 2, 16% grade 3), constipation (17%), oedema (5%), bradycardia (5%), skin reactions (3%), cerebrovascular events (5%) and deep vein thromboses (8%). Thromboses were not related to known thrombophilic risk factors. Four patients with prior myeloma therapy > 50 months developed myelodysplastic syndrome or secondary acute myeloid leukaemia 2-4 months after study entry. HyperCDT is a highly active and reasonably well-tolerated salvage regimen in advanced or refractory multiple myeloma.

Acute Disease↗

PubMed2002

Paracrine interactions of basic fibroblast growth factor and interleukin-6 in multiple myeloma.

Myeloma cells express basic fibroblast growth factor (bFGF), an angiogenic cytokine triggering marrow neovascularization in multiple myeloma (MM). In solid tumors and some lymphohematopoietic malignancies, angiogenic cytokines have also been shown to stimulate tumor growth via paracrine pathways. Since interleukin-6 (IL-6) is a potent growth and survival factor for myeloma cells, we have studied the effects of bFGF on IL-6 secretion by bone marrow stromal cells (BMSCs) and its potential reverse regulation in myeloma cells. Both myeloma-derived cell lines and myeloma cells isolated from the marrow of MM patients were shown to express and secrete bFGF. Cell-sorting studies identified myeloma cells as the predominant source of bFGF in MM marrow. BMSCs from MM patients and control subjects expressed high-affinity FGF receptors R1 through R4. Stimulation of BMSCs with bFGF induced a time- and dose-dependent increase in IL-6 secretion (median, 2-fold; P <.001), which was completely abrogated by anti-bFGF antibodies. Conversely, stimulation with IL-6 enhanced bFGF expression and secretion by myeloma cell lines (2-fold; P =.02) as well as MM patient cells (up to 3.6-fold; median, 1.5-fold; P =.002). This effect was inhibited by anti-IL-6 antibody. When myeloma cells were cocultured with BMSCs in a noncontact transwell system, both IL-6 and bFGF concentrations in coculture supernatants increased 2- to 3-fold over the sum of basal concentrations in the monoculture controls. The IL-6 increase was again partially, but significantly, inhibited by anti-bFGF. The data demonstrate a paracrine interaction between myeloma and marrow stromal cells triggered by mutual stimulation of bFGF and IL-6.

Bone Marrow Cells↗