Comparative evaluation of safety and efficacy of pamidronate and zoledronic acid in multiple myeloma patients (single center experience)

Osteolytic bone destruction, caused by the aberrant production and activation of osteoclasts, results in significant morbidity for patients with multiple myeloma (MM). Pamidronate [(3-amino-1-hydroxypropylidene)-1,1-bis-phosphonate] inhibits osteoclastic activity and reduces bone resorption. A potency of zoledronic acid (2-[imidazol-1-yl]-1-hydroxyethylidene-1,1-bisphosphonic acid, a new third generation bisphosphonate, as inhibitor of resorption was 850-fold greater than pamidronate, as was shown in preclinical models of bone resorption. Randomized, double-blind study was conducted to compare the efficacy and safety of zoledronic acid and pamidronate for treating myeloma bone disease. Since March 1999 the efficacy and safety of pamidronate and zoledronic acid is evaluated in MM patients all receiving anti-myeloma chemotherapy acc. to VMCP/VBAP alternating regimen. Nine patients with stage III myeloma and osteolytic lesions (3 female, 6 male, median age 57 years, range 52-67, with monoclonal protein: IgG-7, IgA-2) were randomly assigned (1:1:1 ratio) to treatment with either 4 or 8 mg of zoledronic acid via 15-minute intravenous infusion or 90 mg of pamidronate via 2-hour intravenous infusion every 3 to 4 weeks for 12 months. All patients have received 500 mg of calcium supplements and 500 IU of vit.D, orally, once daily, for the duration of administration of study medication. In extension phase of the study (June 2000-April 2002) patients did not received bisphosphonates. In 7 patients 18 cycles of assessed treatment was administered to each of them and one patient received 16 cycles. One patient died after receiving of 12 pamidronate therapy cycles at 11 month of the trial duration (and at 49 month since MM diagnosis and anti-tumour treatment). The patient's death occurred during the progression of plasma cell proliferation due to acute left ventricle cardiac failure. During the 12-month-period of bisphosphonate treatment skeletal related events (SRE) and progression of osteolysis occurred with the same frequency in 3 treatment groups. One patient experienced spinal cord compression and received radiation to bone and 2 patients experienced vertebral fracture. Time from study entry to the first SRE was 304 days in pamidronate and 366 and 392 days in 4 and 8 mg zoledronic acid group, respectively. The skeletal morbidity rate was identical in all treatment groups. Single hypocalcemic events occurred in 2 patients, mild hypertransaminasemia was observed in 3, worsening of renal function parameters in 2 patients (transient in one of them). Muscular pain and fever up to 39 degrees C (transient and self-limiting "flu-like" symptoms) occurred in 6 patients after several or some dozens of hours from study drug administration. Adverse events were similar in nature and frequency with zoledronic acid and pamidronate and were experienced by a similar proportion of patients in each treatment group. Median time of patient's observation duration after completing of administered treatment with zoledronic acid and pamidronate amounts to 20 months. At present actual median survival time of analysed patients since MM diagnosis is 42 months, since the beginning of treatment with pamidronate and zoledronic acid--33 months, and since completing treatment--20 months and is similar in 3 treatment groups. As was shown in our single center study in MM patients the safety and efficacy of pamidronate 90 mg and zoledronic acid 4 mg and 8 mg in monthly i.v. infusion are comparable. Thus the recommended dosage of zoledronic acid is 4 mg administered as a 15 minute i.v. infusion at intervals of 3 to 4 weeks.     

Intrathecal bradykinin administration: opposite effects on nociceptive transmission

Injected intrathecally, bradykinin (BK) produced either hyperalgesia (0.15 microg) or antinociception (6.0 microg) in rats when thermal noxious stimuli were used. Similarly, des-Arg(9)-BK at the lower dose (0.15 microg) decreased, whereas at the higher dose (6.0 microg) it increased the threshold to thermal noxious stimuli; however, these effects were less pronounced than those of BK. The antinociception induced by BK was abolished by HOE 140, a B(2) receptor antagonist, injected intrathecally at a dose of 1.3 ng and was markedly attenuated by des-Arg(10)-HOE 140, a B(1) receptor antagonist (1.15 ng i.t.). The results obtained in this study showed that--depending on the dose used--BK and des-Arg(9)-BK could produce pro- as well as antinociceptive actions. Both B(2) and B(1) receptors are involved in the action of intrathecally applied BK.     

Nutrients intake of the adolescents in Poland--ten years literature review (1990-2000)

The dietary survey among adolescents (11-15 years old) performed during last decade in Poland are not representative for national level. The analysis of data obtained by 24-h recall in different regions showed that contribution of dietary fat to energy intake was too high (37-42%), while contribution of proteins (10-11%) and carbohydrates (47-52%) too low. The intake of proteins, fibre, calcium, magnesium, copper and iron (especially among girls), vitamin C and niacin did not meet the recommended levels. The results suggest that girls are more likely to have risk of nutritional deficiencies than boys as well as adolescents from rural area than from towns. Inadequate intake of nutrients during adolescence can increase risk of dietary related diseases in later life.     

Superantigen reactive Vbeta6+ T cells induce perforin/granzyme B mediated caspase-independent apoptosis in tumour cells

The endogenous viral superantigen 7 in DBA/2 mice serves as a target antigen on syngeneic ESb-MP lymphoma cells for allogeneic graft-vs-leukaemia reactive cells. Allogeneic viral superantigen 7 reactive Vbeta6+ T cells are able to transfer graft-vs-leukaemia reactivity and to kill specifically viral superantigen 7+ ESb-MP tumour cells in vitro. Here we elucidate the mechanism of this superantigen specific cell lysis. Already 10 min after co-incubation with in vitro stimulated Vbeta6+ T cells, viral superantigen 7+ ESb-MP tumour cells show an apoptotic phenotype (Annexin V-positivity, DNA-fragmentation). This extremely rapid type of cell death is not mediated by the death inducing ligands CD95L, TRAIL and TNF but by perforin and granzyme B. Surprisingly, neither mitochondria nor any of the known caspases appear to be involved in this type of tumour cell killing. In contrast, nitric oxide, released by activated macrophages and endothelial cells, induces in the same tumour cells another type of apoptosis which is much slower and involves mitochondria and caspase activation. A synergistic effect between the two different effector mechanisms of superantigen reactive donor cytotoxic T lymphocytes and nitric oxide releasing host macrophages and endothelial cells might explain the effective immune rejection of even advanced metastasised cancer in this graft-vs-leukaemia animal model.     

Transplants as a therapy after spinal cord injury

This review describes shortly phenomena that take place in different parts of central nervous system (CNS) after the spinal cord injury: 1/ due to axotomy many of neurones present outside the cavity of lesion (even those of supraspinal origin) can atrophy or die as an effect of necrosis or apoptosis; 2/ at the injury site itself, the primary and secondary effects lead to increased cell loss and the scar or cyst formation that are the mechanical barrier for regenerating axons; 3/ due to abolished conduction across the injury site the spinal cord circuitry below the lesion is deprived of supraspinal inputs. Then this review presents the new therapeutic strategies that were developed recently to obtain at least partial recovery of motor functions after spinal cord injury. The cell body can be rescued by applying various factors that increase intrinsic neural repair (e.g. neurotrophins or anti-apoptotic agents). To enhance the axonal regrowth through the lesion cavity, the scar and cyst formation can be reduced by constructing the bridges using e.g. the Schwann cells, fetal tissue, stem cells, olfactory ensheating glial cells, or by application of macrophages. To induce partial restoration of some functions that are controlled by neural circuitry below the lesion the various methods for enhancing the plasticity in segmental circuitry were developed (e.g. rehabilitation by locomotor training or intraspinal transplantation of monoaminergic cells). As a consequence of the great unpredictability of effects obtained after injury at different parts of the spinal cord the various strategies for repair need to be coordinated for optimal recovery.     

Naked DNA vaccination differentially modulates autoimmune responses in experimental autoimmune encephalomyelitis

Vaccination with naked DNA represents a therapeutic strategy currently under consideration in multiple sclerosis (MS). In this study, we tested the potential therapeutic effect of vaccination with a naked DNA construct encoding proteolipid protein (pRc/CMV-PLP) upon the outcome of subsequent sensitization for experimental autoimmune encephalomyelitis (EAE) actively-induced in SJL mice with PLP139-151 peptide in adjuvant. Intramuscular vaccination with the naked DNA pRc/CMV-PLP construct led to PLP expression in local muscle tissue that persisted for about 8 weeks. Early sensitization for EAE (4 weeks after DNA vaccination) caused recipient mice to develop a severe, exacerbated form of disease (in comparison to control mice), while late sensitization (>10 weeks) resulted in a milder, ameliorated form. In the groups sensitized <10 weeks post-DNA vaccination with pRc/CMV-PLP induction of a Th1-type cytokine response was noted. In contrast, sensitization >10 weeks post-DNA vaccination led to peripheral tolerance as evidenced by a decrease in T cell proliferation and cytotoxic T cell response, no Th2 response, and no increase in apoptosis. These data are novel in that they demonstrate a differential effect of DNA vaccination and have important implications for its use as a mechanism to enhance or modulate immune reactivity.     

Tumor necrosis factor-related apoptosis-inducing ligand retains its apoptosis-inducing capacity on Bcl-2- or Bcl-xL-overexpressing chemotherapy-resistant tumor cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor family and has recently been shown to exert tumoricidal activity in vivo in the absence of any observable toxicity. The signaling pathways triggered by TRAIL stimulation and the mechanisms involved in resistance against TRAIL-mediated apoptosis are still poorly defined. We show here that TRAIL-induced apoptosis involves late dissipation of mitochondrial membrane potential (delta psi(m)) and cytochrome c release. These events follow activation of caspase-8 and caspase-3 and induction of DNA fragmentation. In addition, caspase-8-deficient cells are resistant against TRAIL-induced apoptosis, and inhibition of caspase-8 but not caspase-9 prevents mitochondrial permeability transition and apoptosis. In contrast, various Bcl-2- or Bcl-xL-overexpressing tumor cell lines are sensitive to TRAIL-induced apoptosis; however, they show a delay in TRAIL-induced mitochondrial permeability transition compared with control transfectants. This indicates that TRAIL-induced apoptosis depends on caspase-8 activation rather than on the disruption of mitochondrial integrity. Because most chemotherapeutic drugs used in the treatment of malignancies lead to apoptosis primarily by engagement of the mitochondrial proapoptotic machinery, we tested whether drug-resistant tumor cells retain sensitivity for TRAIL-induced apoptosis. Tumor cells overexpressing Bcl-2 or Bcl-xL become resistant to apoptosis induced by the chemotherapeutic drug etoposide. However, these cells are not protected or are only marginally protected against TRAIL-induced apoptosis. Thus, TRAIL may still kill tumors that have acquired resistance to chemotherapeutic drugs by overexpression of Bcl-2 or Bcl-xL. These data will influence future treatment strategies involving TRAIL.