Multiple myeloma: new aspects of biology and treatment

Recently, considerable progress has been made in understanding of the biology and treatment of multiple myeloma. Molecular genetic abnormalities such as bcl-2,c-myc, ras, p53, and Rb genes have been identified in this disease and are related to a poor prognosis. Cytokine studies have revealed that interleukin-6 is a potent growth factor for myeloma cells and is also responsible for the progressive bone resorption together with interleukin-1 beta and tumor necrosis factor. Myeloablative chemotherapy followed by allogeneic or autologous hematopoietic stem cell transplantation has increased the incidence of complete remission. However, relapses are still observed because of drug resistance of tumor cells. Immunotherapeutic approaches targeting to cell surface antigens and interleukin-6 signals are being developed to further eliminate myeloma cells. Translating new biological advances into treatment protocols is essential to improve the prognosis of multiple myeloma.

Hepatosplenic gamma delta T-cell lymphoma associated with hepatitis B virus infection

Hepatitis B virus (HBV) infection has been implicated in the development of hepatocellular and hematopoietic malignancies. We describe a patient with chronic hepatitis B who developed hepatosplenic gamma delta T-cell lymphoma. A 45-year-old woman presented with marked hepatosplenomegaly and hepatic failure during the course of chronic hepatitis B. Peripheral blood examination revealed 57% abnormal lymphoid cells which expressed the gamma delta T-cell receptor. The cytogenetic analysis of tumor cells showed an abnormal karyotype; 47, XX, -13, +2mar in all 20 metaphases examined. A clonal rearrangement of the T-cell receptor genes was demonstrated by Southern blot analysis, showing monoclonal expansion of tumor cells. A liver biopsy specimen showed fibrosis of the portal areas and sinusoidal infiltration of tumor cells. HBV infection was documented by the presence of IgG anti-HBc and anti-HBs antibodies in serum. Although HBV-DNA was not detected in tumor cells by polymerase chain reaction analysis, there is a possibility that proliferation of gamma delta T cells in response to HBV infection played a role in the pathogenesis of hepatosplenic gamma delta T-cell lymphoma.

Prevalence and characterization of perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) directed against HMG1 and HMG2 in ulcerative colitis (UC)

In a previous study, we reported that the high mobility group (HMG) non-histone chromosomal proteins HMG1 and HMG2 were novel target antigens of P-ANCA. In this study, we determined the immunodiagnostic value of anti-HMG1/HMG2 antibodies in patients with UC. Sixty sera from patients with UC were tested for reactivity with HMG1 and HMG2 by means of ELISA. Anti-HMG1 antibody was detected in 32% of patients (40% of P-ANCA+ patients). Anti-HMG2 antibody was detected in 33% (40% of P-ANCA+ patients). Thirty-five percent of sera were positive for antibody to either HMG1 or HMG2 (43% of P-ANCA+ patients). P-ANCA+ patients expressed anti-HMG1/HMG2 antibodies with significantly greater frequency compared with P-ANCA- patients. Furthermore, the anti-HMG1/HMG2 antibodies were significantly related to disease activity in UC. Sixteen of the 18 UC patients, who had high titres of anti-HMG1 or -HMG2 antibody during the active phase, showed lower titres in the inactive phase. Anti-HMG1/HMG2 antibodies appear to be useful as a marker for disease activity in UC.

[A case of lung cancer with pericardial effusion without cardiac tamponade]

Cardiac tamponade as an initial manifestation of primary lung cancer is uncommon. All such cases had shown symptoms of cardiac tamponade at the first visit of the hospital. We report a case of lung cancer with pericardial effusion without cardiac tamponade. Echocardiography, revealed little pericardial effusion and it has not increased for 3 months. Pericardiotomy revealed adenocarcinoma and lung cancer was confirmed by bronchial biopsy. It is necessary to further examine patients with even slight amounts of pericardial effusion.

[Clinical evaluation of benign asbestos pleurisy]

Seventeen cases of benign asbestos pleurisy were evaluated clinically. All cases were male and almost all cases were more than 60 years-old. Most cases presented with chief complaints of chest pain and dyspnea, but 2 cases had no complaints. Pleural effusion appeared predominantly in the right side. Six cases had 2 or 3 episodes of pleural effusion, and 1 case had 5. Ten cases had an occupational history of asbestos exposure in shipyards and 5 other cases had a history in building construction. Almost all cases had more than 30 years of exposure to asbestos and benign asbestos pleurisy appeared after more than 30 years from the first exposure to asbestos. Among the patients, 6 cases had diffuse pleural thickening and 2 cases had malignancies. Pleural fluid was bloody in 14 of 17 cases (82%) and all pleural fluid showed an exudate. Lymphocytes represented 70% and eosinophils 15% of the cellular population of the pleural fluid. Hyaluronic acid in pleural fluid in cases of benign asbestos pleurisy averaged 29.5 micrograms/ml, which was significantly (p < 0.05) lower than in malignant pleural mesothelioma. Leukocytosis in peripheral blood and a high CRP value were uncommon in benign asbestos pleurisy.

Enhanced apoptosis relates to bile duct loss in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized by an immune-mediated destruction of intrahepatic small bile ducts. Apoptosis, a unique pattern of cell death, has been suggested to be responsible for the biliary destruction in PBC. To address this issue, we attempted to detect the apoptosis of biliary epithelial cells by in situ nick-end labeling and by the expression of apoptosis-related proteins using immunohistochemistry in patients with various hepatobiliary diseases, including PBC. The data was noteworthy for several reasons. First, apoptosis was occasionally detected on biliary cells in all liver specimens; however, the positive rate was high in PBC and relatively low in other livers. Strong expression of CD95 was frequently observed in the epithelial cells of the injured bile ducts of PBC, which accompanied high intensity CD95 ligand-expressing mononuclear cells. Perforin and granzyme B immunoreactivities were occasionally found on the bile ducts in control liver diseases as well as PBC, but granzyme B-positive biliary cells were prominent in PBC. In contrast, Lewis Y expression, as detected using BM-1 antibody, was consistently present in the injured bile ducts of PBC. These data suggest that apoptosis, via the perforin/granzyme B pathway, may be associated with the degrading fraction of cell cycle regulation in the small-sized biliary tree under physiological and pathological liver conditions. Moreover, enhanced apoptosis, mediated by CD95/CD95 ligand interaction, may contribute to the bile duct injury and loss observed in PBC.

Kidney-specific expression of a novel mouse organic cation transporter-like protein

Using the signal sequence trap method, we have cloned a novel 12-membrane-spanning transporter-like protein, termed renal-specific transporter (RST), from the mouse kidney. RST is a 553-amino-acid protein highly homologous to recently cloned organic cation transporters, e.g. it is 30% identical to rat organic cation transporter I at the amino acid level. Northern blot analysis has revealed that the RST gene is expressed abundantly and specifically in the kidney. In situ hybridization analysis has shown that RST gene expression is restricted to the renal proximal tubule, where various organic cations such as endogenous catecholamines and choline or clinically used cationic drugs are known to be actively excreted.

Sleep and mood disorders

Mood disorders are found in one-third to one-half of patients with chronic sleep problems. Likewise, most patients with mood disorders experience insomnia, but a minority obtain significantly increased amounts of sleep. Although mood disorders cause significant morbidity and mortality, they often go undiagnosed. Attention to sleep complaints could lead to better identification of mood disorders. Management of sleep problems in patients with mood disorders should focus on treating underlying mood disorders with attention to the nature of the sleep complaint. Patients with depression show characteristic abnormalities in sleep continuity, slow-wave sleep and REM sleep patterns. Differences in sleep patterns cannot reliably distinguish patients with depression from those with other psychiatric disorders, but sleep changes may provide a window on neurobiologieal abnormalities in depression.

Immunotherapy of multiple myeloma with a monoclonal antibody directed against a plasma cell-specific antigen, HM1.24

Multiple myeloma remains an incurable malignancy because of marked resistance of tumor cells to conventional chemotherapeutic agents. Alternative strategies are needed to solve these problems. To develop a new strategy, we have generated a monoclonal antibody (MoAb), which detects a human plasma cell-specific antigen, HM1.24. In this report, we evaluated the in vivo antitumor effect of unconjugated anti-HM1.24 MoAb on human myeloma xenografts implanted into severe combined immunodeficiency (SCID) mice. Two models of disseminated or localized tumors were established in SCID mice by either intravenous or subcutaneous injection of human myeloma cell lines, ARH-77 and RPMI 8226. When mice were treated with a single intraperitoneal injection of anti-HM1.24 MoAb 1 day after tumor inoculation, the development of disseminated myeloma was completely inhibited. In mice bearing advanced tumors, multiple injections of anti-HM1.24 MoAb reduced the tumor size and significantly prolonged survival, including tumor cure, in a dose-dependent manner. The proliferation of cultured human myeloma cells was inhibited in vitro by anti-HM1.24 IgG-mediated complement-dependent cytotoxicity, but not by the antibody alone. Moreover, spleen cells from SCID mice mediated antibody-dependent cell cytotoxicity against RPMI 8226 cells. These results indicate that anti-HM1.24 MoAb can be used for immunotherapy of multiple myeloma and related plasma cell dyscrasias.

5-Fluorouracil derivatives. XXII. Synthesis and antitumor activities of 1-carbamoyl-5-fluorouracils

Fifty-four 1-carbamoyl-5-fluorouracils were synthesized from 5-fluorouracil and isocyanate or amine. Antitumor activity was tested in the L-1210 tumor system, and 11 compounds gave better values of therapeutic ratio than HCFU (1-hexylcarbamoyl-5-fluorouracil). 1-(4-Methoxycyclohexylcarbamoyl)-5-fluorouracil gave the best result.

Purification and characterization of beta-N-acetylgalactosaminidase from Bacillus sp. AT173-1

Beta-N-Acetylgalactosaminidase [EC 3.2.1.53] was purified to homogeneity from the culture media of Bacillus sp. AT173-1. The enzyme has a molecular weight of 48,000 as estimated by SDS-PAGE under reducing conditions and an isoelectric point of 4.3. The enzyme requires dithiothreitol as an activator and is most active at pH 6.0. Analysis of its substrate specificity using 2-aminopyridine-labeled oligosaccharides as substrates revealed the enzyme specifically hydrolyzes beta-N-acetylgalactosaminyl linkages of GalNAcbeta1-4Galbeta1-4Glc, GalNAcbeta1-3Gal alpha1-4Galbeta1-4Glc, and N-glycans terminating with beta-N-acetylgalactosamine residues but not those with beta-N-acetylglucosamine residues. The enzyme is thus a novel beta-N-acetylgalactosaminidase with practically no beta-N-acetylglucosaminidase activity.

Thrombopoietin-responsive essential thrombocythaemia with myelofibrosis

Platelet-derived growth factor (PDGF) and other cytokines released from megakaryocytes are thought to play a crucial role in the pathogenesis of myelofibrosis. We describe a patient with essential thrombocythaemia (ET) who developed myelofibrosis with an increased level of serum thrombopoietin (TPO). Recombinant human (rh) TPO stimulated the proliferation and spontaneous megakaryocyte colony formation of the neoplastic cells in the peripheral blood. Moreover, serum concentrations of PDGF, platelet factor 4, and beta-thromboglobulin were elevated and the production of these growth factors from the megakaryocyte progenitors was augmented with the addition of rhTPO in vitro. These results indicate that TPO may contribute to the development of myelofibrosis in ET.

Initial trajectories of sensory axons toward laminar targets in the developing mouse spinal cord

The formation of laminar-specific projections is a key event in the development of appropriate neuronal connections in many regions of the central nervous system. In order to provide a framework for defining functions of molecules related to spinal laminar targeting of dorsal root ganglion neurons in mice, we have characterized the initial trajectories of sensory axons in relation to the maturation of their target laminae in the spinal cord. We show that morphological and biochemical differentiation of distinct clusters of neurons in the dorsal region of the spinal cord precedes initial collateral branching from sensory axons. Between embryonic day (E) 12.5 and E13.5, sensory axons develop swelling ("nodes") along their entire intraspinal extent and elaborate interstitial collateral branches from these nodes. Collaterals from the different classes of sensory axons then penetrate the gray matter of the spinal cord sequentially. Each class of sensory axons projects directly to its target lamina, never branching into inappropriate laminae en route. Some cutaneous afferents traverse the entire width of the spinal cord to reach superficial laminae on the contralateral side, strictly avoiding both the ventral spinal cord and inappropriate laminae of the deep dorsal horn. The pathways taken by developing sensory afferents are compatible with the idea that cells in inappropriate laminae exert inhibitory influences on sensory axons which regulate their laminar specificity.

Influence of the sensory retina on healing of the rabbit retinal pigment epithelium

PURPOSE

To compare the healing process of the retinal pigment epithelium (RPE) with and without the overlying sensory retina.

METHODS

A dome-shaped retinal detachment was created in the pigmented rabbit eye by injecting balanced salt solution into the subretinal space. The detached retina was partially removed with a vitrector; in some eyes, the detached retina was removed completely. RPE about 1.5 mm in diameter was removed from Bruch's membrane and aspirated through the retinal break. All eyes were examined morphologically.

RESULTS

Independent of the sensory retina, 4 days postoperatively the RPE wound was covered by immature RPE cells that gradually formed an epithelial-like sheet by 2 weeks postoperatively. In eyes with overlying sensory retina, regenerated RPE cells similar to normal RPE cells formed a monolayer in most areas. The RPE-photoreceptor outer segment interface gradually organized. In eyes with no sensory retina, the regenerated RPE cells were longer, mounded, and their microvilli were shorter and disorganized. The RPE cells were multilayered in some areas and often had a tubuloacinar structure.

CONCLUSIONS

The RPE wounds healed rapidly, independent of the presence of the overlying sensory retina, up to 2 weeks after RPE removal. Reconstruction of the RPE monolayer and the apical morphology of regenerated RPE cells were influenced by the sensory retina.

Coexpression studies with endothelin receptor subtypes indicate the existence of intracellular cross-talk between ET(A) and ET(B) receptors

Human Girardi heart cells expressing endothelin ET(B) receptors (GH(B) cells) were transfected with human ET(A) cDNA, and coexpression of ET(A) and ET(B) in the ratio of 4:6 was demonstrated by Scatchard analysis. [125I]Endothelin (ET)-1 binding to ET(A)-transfected GH cells (GH(AB) cells) was displaced by an ET(A) antagonist, BQ-123, in a biphasic manner. An ET(B) agonist, BQ-3020, and an ET(B) antagonist, BQ-788, inhibited [125I]ET-1 binding to GH(AB) cells in a monophasic manner with low affinities (IC50 = 2,800 and 890 nM, respectively); IC50 values for ET(B) receptors seemed to be as weak as those for ET(A) receptors. However, BQ-3020 and BQ-788 had a high affinity for ET(B) receptors in a binding experiment using [125I]ET-1 in the presence of 1 microM BQ-123, where ET(A) receptors are masked (IC50 = 0.49 and 0.89 nM, respectively). The ET(B)-mediated increase in intracellular calcium concentrations in GH(AB) cells was not affected by 0.1 microM BQ-788 alone but was inhibited significantly by the same concentration of BQ-788 in combination with 10 microM BQ-123. ET-1 suppressed forskolin-stimulated accumulation of cAMP through the activation of ET(A) and ET(B) in GH(AB) cells; 1 microM BQ-123 or BQ-788 inhibited the suppression by only 20%, whereas a mixture of BQ-123 and BQ-788 (1 microM each) completely inhibited the cAMP decrease. These findings suggest that the stimulation of ET(A) receptors with ET-1 results in a lowering of the affinity of BQ-3020 and BQ-788 for ET(B) receptors in GH(AB) cells. We conclude that there is intracellular cross-talk between ET(A) and ET(B) receptors in GH(AB) cells.

[Unilateral mixed-dust pneumoconiosis with aluminum deposition associated with interstitial pneumonia]

A 63-year-old stoneworker complained of fever and a productive cough. His chest roentgenogram showed a nodular mass and a diffuse interstitial shadow in the right lung. Angiography of the pulmonary artery revealed obstruction of the right upper trunk. Open-lung biopsy was done. Histologic examination showed mixed-dust pneumoconiosis with a massive focus of mixed-dust fibrosis with silicotic nodules, and diffuse interstitial fibrosis of pattern with lymphoid infiltration. Chemical analysis revealed a high content of aluminum in lymph node, which was thought to be due to inhalation of alumina used for lettering stones. The unilateral interstitial pneumonia was thought to have developed due to deposition of free silica and aluminum dust. Although this patient had been given a diagnosis of rheumatoid arthritis and the value of rheumatoid factor was high, the interstitial pneumonia was not believed to be associated with the collagen vascular disease.

Molecular cloning of a novel mouse aspartic protease-like protein that is expressed abundantly in the kidney

By use of the signal sequence trap method, we isolated a cDNA encoding a novel aspartic protease-like protein from the mouse kidney, and termed it 'kidney-derived aspartic protease-like protein (KAP).' The protein, a 419-amino-acid polypeptide with a 16-amino-acid signal sequence, had 47% identity with mouse cathepsin D, and its overall structure was closely related to known aspartic proteases. Northern blot analysis revealed that KAP mRNA is expressed at the highest level in the kidney, at a moderate level in the lung, and at low levels in the spleen and adipose tissue. In situ hybridization analysis demonstrated that the mRNA is expressed abundantly in the proximal straight tubule and slightly, but significantly, in the proximal convoluted tubule in the kidney. This intra-renal distribution differs distinctly from those of previously reported proteases such as cathepsins B, D, and H.

Cholinergic mechanisms responsible for blood pressure regulation on sympathoexcitatory neurons in the rostral ventrolateral medulla of the rat

We examined whether reticulospinal sympathoexcitatory neurons in the rostral ventrolateral medulla (RVLM) have muscarinic receptors and ACh inputs, and whether these cholinergic mechanisms on RVLM neurons are involved in the pressor response induced by peripheral administration of physostigmine. Microiontophoretic application of ACh and carbachol enhanced the firing rate of RVLM sympathoexcitatory neurons and the enhancement of RVLM neurons by these cholinoceptor agonists was abolished by the nonselective muscarinic receptor antagonist scopolamine and/or by the M2 muscarinic receptor antagonist methoctramine. Physostigmine and the ACh releaser 3,4-diaminopyridine also enhanced the firing rate of RVLM neurons. Intravenous administration of physostigmine enhanced RVLM sympathoexcitatory neuronal activity and the physostigmine-induced response was reversed by iontophoretic application of scopolamine onto the neurons. These results are consistent with the hypothesis that M2 muscarinic receptors responsible for blood pressure regulation are present on RVLM sympathoexcitatory neurons and these receptors receive ACh inputs. Physostigmine injected systemically may exert a portion of its hypertensive effect through a direct enhancement of cholinergic mechanisms on RVLM sympathoexcitatory neurons.

Novel autoantigens of perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) in ulcerative colitis: non-histone chromosomal proteins, HMG1 and HMG2

Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from ulcerative colitis (UC) patients have been described as reacting with proteins in the granules of human neutrophils such as cathepsin G and lactoferrin and with yet unidentified antigens. Here we report the existence of a new member of perinuclear ANCA (P-ANCA) in UC patients. In the previous study, we found that UC patients had a novel P-ANCA against neutrophil 28-kD protein. In this study, we purified the same antigens from HL-60 lysates by using reversed phase high-performance liquid chromatography, and revealed that the 28-kD antigen consisted of two different proteins. The N-terminus amino acids of these proteins are identical with those of high mobility group (HMG) non-histone chromosomal proteins HMG1 and HMG2. Immunoblotting analysis of human neutrophil lysates using rabbit anti-HMG1/2 antisera revealed a single band of 28 kD, and the 28-kD band detected by immunoblotting analysis using patient's serum IgG completely disappeared after preincubation with a mixture of HMG1 and HMG2. Furthermore, rabbit anti-HMG1/2 antisera showed a perinuclear staining pattern in indirect immunofluorescence studies using ethanol-fixed neutrophils. These data demonstrate that HMG1 and HMG2 are novel target antigens of P-ANCA. HMGI and HMG2 are distributed in the nuclei and cytoplasm of eukaryotic cells and act as transcription factors. Their intracellular localization and functions are distinct from those of the previously reported granular antigens of P-ANCA.

Development of locomotor activity induced by NMDA receptor activation in the lumbar spinal cord of the rat fetus studied in vitro

The development of neuronal circuits generating locomotor activity was characterized in an isolated lumbar spinal cord preparation from of fetal and neonatal rats. Locomotor activity induced by bath application of the NMDA receptor agonists, NMA and NMDA, was monitored from both sides of the corresponding lumbar ventral roots. Activation of NMDA receptors first evoked rhythmic motor activity at E15.5. NMA-induced rhythmic motor activity was not observed under synaptic blockade by TTX or cadmium ions, suggesting that this activity was evoked by synaptic drive from the interneuronal circuits in the spinal cord. At E15.5-E16.5, the rhythmic motor activity on both sides was synchronized. Phase relationship of the rhythmic motor activity between both sides was variable at E17.5-E19.5. The rhythmic motor activity was alternating on both sides at E20.5. Mid-sagittal splitting of the spinal cord did not affect the rhythm generation at all stages examined, suggesting the existence of independent rhythm-generating circuits on each side. The rhythmic motor activity in the presence of strychnine was synchronized on both sides at all stages examined. These results indicate that the changes in rhythm pattern are mediated by development of glycinergic inhibitory pathways, while the basic rhythm can be generated without the glycinergic inhibitory pathways.

Spontaneous motoneuronal activity mediated by glycine and GABA in the spinal cord of rat fetuses in vitro

1. Spontaneous motoneuronal activity was monitored from the lumbar ventral roots in an isolated spinal cord preparation from rat fetuses at embryonic days (E) 13.5-18.5. 2. Spontaneous bursts that were synchronized in both left and right ventral roots were observed periodically (mean interval, 1.5-2.6 min) from E14.5 to 17.5. This activity was abolished in Ca(2+)-free saline or by application of tetrodotoxin (1 microM), indicating that it was synaptically mediated. 3. The glutamate receptor blocker kynurenate (4 mM) failed to block spontaneous bursts at E14.5-15.5, though it completely abolished them at E17.5. The glycine receptor antagonist strychnine (10 microM) completely blocked spontaneous bursts at E14.5-15.5. Bicuculline, a GABAA receptor antagonist, reduced the amplitude of the spontaneous bursts. 4. At E15.5, a brief application of glycine (250 microM to 2 mM) evoked excitatory responses resembling the spontaneous bursts in both time course and amplitude. Such glycine-induced responses were not observed under Ca(2+)-free conditions, suggesting that they were synaptically evoked. These synaptic responses were not blocked by kynurenate (4 mM), but they were abolished by strychnine (10 microM). 5. It is concluded that glycine and GABA generate the earliest spontaneous motor activity of the fetus and function transiently as excitatory transmitters in the embryonic spinal cord.

Isolation of the active form of RAC-protein kinase (PKB/Akt) from transfected COS-7 cells treated with heat shock stress and effects of phosphatidylinositol 3,4,5-trisphosphate and phosphatidylinositol 4,5-bisphosphate on its enzyme activity

RAC-protein kinase (PKB/Akt) has been shown to be activated by growth factor stimulation as a downstream target of phosphatidylinositol 3-kinase and also by heat shock through a pathway independent of phosphatidylinositol 3-kinase. RAC-protein kinase was purified by antibody affinity chromatography from COS-7 cells transfected with the epitope-tagged expression plasmid. The protein kinase activity of RAC-protein kinase purified from heat-treated cells was 9-fold higher than the enzyme isolated from untreated control cells. Phosphatidylinositol 3,4,5-trisphosphate did not enhance the activity of RAC-protein kinase purified from either heat-treated cells or control cells, whereas phosphatidylinositol 4,5-bisphosphate suppressed the enzyme isolated from heat-treated cells. These results indicate that RAC-protein kinase may interact with phosphoinositides, however, it could not be activated by simple association with the product of phosphatidylinositol 3-kinase reaction.