The RCK gene associated with t(11;14) translocation is distinct from the MLL/ALL-1 gene with t(4;11) and t(11;19) translocations

We previously demonstrated that the 11q23 breakpoint region, designated the RCK locus, of the RC-K8 B-lymphoma cell line with t(11;14)(q23;q32) is centromeric to PBGD, while breakpoints of infantile leukemia cell lines with t(11;19)(q23;p13) are detectable by pulsed-field gel electrophoresis with the CD3D probe. In the present study, using a probe within 1.0 kilobase of the t(11;14) breakpoint, we isolated a partial complementary DNA clone for the putative RCK gene, which detects a 7.5-kilobase mRNA. Sequence analysis predicted a novel protein of 472 amino acids which demonstrated sequence homology to a translation initiation factor/helicase family. We also isolated a phage clone from the CD3D/G yeast artificial chromosome clone (yB22B2) which detects 11- and 12-kilobase mRNAs, most likely for the MLL/ALL-1 gene associated t(4;11)(q21;q23) and t(11;19)(q23;p13) translocations. By pulsed-field gel electrophoresis after NotI digestion, this recombinant clone is on a 96-kilobase fragment, while RCK and PBGD probes are on a more telomeric 690-kilobase NotI fragment. These results, altogether, suggested that two different genes, RCK and MLL/ALL-1, are associated with 11q23 translocation of hematopoietic tumors.

The establishment of an interleukin-6-dependent myeloma cell line (FLAM-76) carrying t(11;14)(q13;q32) chromosome abnormality from an aggressive nonsecretory plasma cell leukemia

A new myeloma cell line designated FLAM-76 was established from a patient with an aggressive nonsecretory plasma cell leukemia. The cell line exhibited morphologic features of flaming cells and contained an abundant eosinophilic cytoplasm with many dilated cisternae of rough endoplasmic reticulum. FLAM-76 cells were positive for cytoplasmic kappa (kapp)-type immunoglobulin but did not secrete it into the culture medium. The cells proliferated in the presence of exogenous interleukin-6 (IL-6) and more than 800 pg/ml of IL-6 was necessary for their continuous growth. The cells did not grow without IL-6, and they did not produce IL-6. Thus, the growth of FLAM-76 appeared to be regulated by the paracrine mechanism of IL-6. Alpha-interferon (alpha-IFN) inhibited the IL-6-dependent growth of FLAM-76 in doses greater than 1000 U/ml. FLAM-76 cells expressed CD38 (OKT10) and cell adhesion-associated antigens such as CD44 and CD54 (ICAM-1). Chromosome analysis revealed FLAM-76 to have a hypodiploid chromosome constitution with t(11;14)(q13;q32) abnormality, which frequently is seen in neoplasms of B-cell origin. Immunoglobulin (JH and Ck) gene rearrangement (but no BCL-1 gene rearrangement) was found in this cell line.

Histogenesis of diffuse small cleaved cell lymphoma. An immunohistochemical and molecular genetic (bcl-2 gene) study with comparison to follicular small cleaved cell lymphoma and mantle zone lymphoma

Immunohistochemical and molecular genetic (bcl-2 gene) studies were performed on specimens from 24 patients with follicular small cleaved cell lymphoma (FSCCL), 24 patients with diffuse small cleaved cell lymphoma (DSCCL) and 4 patients with mantle zone lymphoma (MZL) to determine the cellular origin of the disease and whether or not DSCCL represents the diffuse counterpart of FSCCL. Two patients with FSCCL, 22 patients with DSCCL, and all of the patients with MZL had a phenotype of mantle zone (MZ) B-lymphocytes (SIgD+, Leu-1+, Leu-8+, positive alkaline phosphatase [ALPase+], and negative common acute lymphoblastic leukemia antigen [CALLA-]), and all the tested patients (2 patients with FSCCL, 13 patients with DSCCL, and 4 patients with MZL) had germlines of bcl-2 gene. Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements. These results indicate that FSCCL are almost always derived from FCC, whereas some FSCCL, most DSCCL, and all MZL are derived from MZ B-lymphocytes, and these lymphomas should be included in the same category as MZ B-lymphocyte-derived lymphomas. Histologically diagnosed DSCCL often may represent a diffuse counterpart of MZ B-lymphocyte-derived lymphoma. MZ B-lymphocyte-derived lymphomas histologically show a follicular (nodular), a follicular MZ, or a diffuse growth pattern and clinically show a high incidence of peripheral blood (PB) involvement or bone marrow (BM) involvement.

Gene rearrangement and overexpression of PRAD1 in lymphoid malignancy with t(11;14)(q13;q32) translocation

The proto-oncogene PRAD1 (parathyroid adenoma 1) on chromosome 11q13 was found to be overexpressed in all five B-cell lines with t(11;14)(q13;q32) translocation tested. One B-cell lymphoma and four myeloma cell lines with this translocation demonstrated more than 10-fold overexpression as determined by Northern blot analysis, when compared with normal lymphoid tissues such as thymus, spleen and lymph node. Hematopoietic cell lines without the translocation were also examined, but none of these demonstrated the overexpression, confirming that overexpression of the PRAD1 gene is associated with t(11;14) translocation. A truncated form of mRNA was seen in one of five cell lines with the translocation, SP-49. Hybridization with different regions of the PRAD1 cDNA revealed that the truncated form of mRNA retained the coding region but had lost the 3' untranslated region. Southern blot analysis demonstrated a gene rearrangement in this SP-49 cell line. To study the genetic alteration responsible for the truncated form of mRNA in this cell line, the rearranged allele as well as the germline allele were cloned. The restriction map revealed that the rearranged portion was at the 3' end of the PRAD1 gene, eliminating the mRNA-destabilizing signal AUUUA. Human-rodent hybrid cell analysis demonstrated that the region introduced 3' of PRAD1 was derived from chromosome 11, suggesting that the PRAD1 gene region is deleted at the 3' end. Over-expression of the PRAD1 gene in association with t(11;14)(q13;q32) translocation suggested that in these cases the regulation of PRAD1 was altered by the juxtaposed gene, most likely the immunoglobulin heavy-chain gene from chromosome 14.

CD7 expression in malignant pleural mesothelioma

CD7 antigen was found to be expressed on malignant mesothelioma arising from the right pleura in a 15-year-old girl not only by immunostaining using monoclonal antibodies, but also by Northern blot analysis. The level of expression in this tumor was comparable to those in T-cell lines, Jurkat and CCRF-CEM. Cytogenetic analysis of the tumor showed hypodiploidy (n = 43). CD7 has been regarded as one of the hematopoietic cell markers selectively expressed on the majority of T cells and multipotential stem cells. To our knowledge, this is the first report of a non-hematopoietic tumor expressing CD7.

[Overexpression of PRAD1 gene in B-cell malignancy with t(11;14)(q13;q32) translocation]

PRAD1 (parathyroid adenoma 1) gene at chromosome 11q13 has been cloned from parathyroid adenomas as a putative oncogene, activated by translocation with the parathyroid hormone gene. 4.5 kb and 1.7 kb mRNA are transcribed and both have the same open reading frame of 885 bp encoding 34 kd protein of a cyclin gene family, cyclin D1. Recently, overexpression of PRAD1 gene has been reported to be correlated closely with the rearrangement of bcl-1 locus, particularly in centrocytic lymphoma. In our study, overexpression of PRAD1 gene was shown in five B cell lines with t(11;14)(q13;q32) including one centrocytic lymphoma line and 4 myeloma lines, when compared with other hematopoietic cell lines without translocation. One of the cell lines, SP-49, demonstrated a truncated mRNA of 3.4 kb, in addition to 1.7 kb of normal size. Southern blot analysis demonstrated a rearrangement with PRAD1 cDNA probe, suggesting that the gene is altered in this particular cell line. By cloning analysis, we confirmed that 1.8 kb deletion in 3' region of PRAD1 gene eliminating the destabilizing signal of PRAD1 mRNA, gave rise to the aberrant mRNA of 3.4 kb. These findings suggest that PRAD1 gene is most likely the candidate oncogene for bcl-1 activated by t(11; 14)(q13;q32) translocation. The gene alteration found in one cell line, SP-49, might also play an important role for deregulation of the gene.

Phenotypic and genotypic lineage switch of a lymphoma with shared chromosome translocation and T-cell receptor gamma gene rearrangement

A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) gamma gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR delta/alpha gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR delta/alpha gene complex was studied. The result showed that two rearrangements of TCR alpha gene detected with J alpha probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma.

An outbreak of Legionnaires' pneumonia in a nursing home

An outbreak of Legionnaires' pneumonia occurred at a nursing home in December 1990. A 79-year-old female and a 73-year-old male clerk who were staying at the nursing home developed pneumonia with only a 5-day interval. Legionella pneumophila serogroup I was isolated from transtracheal aspirate of the former and sputum of the latter. After treatment with a combination of erythromycin and rifampicin both patients improved. Serological surveillance of inpatients and staff of the nursing home was performed in February 1991. Seven out of 51 samples (14.0%) showed a titer higher than 1:128 of anti-Legionella pneumophila serogroup I antibody determined by indirect immunofluorescence; two of these seven complained of respiratory symptoms. Molecular epidemiology analyzed by restriction endonuclease digestion of isolated L. pneumophila showed an identical pattern which suggested a common origin.

Rearrangements on chromosome 11q23 in hematopoietic tumor-associated t(11;14) and t(11;19) translocations

We previously demonstrated that the breakpoint of t(11;14)(q23;q32) in the RC-K8 B cell lymphoma cell line lies between CD3 and THY1/ETS1 on chromosome 11q23, and we cloned this region and named it the rck locus. Pulsed-field gel electrophoresis showed that the rck probe B (distal to the breakpoint) and the porphobilinogen deaminase (PBGD) probe detect the same germ line band and also the same rearranged band when DNA from RC-K8 cells was digested with NotI enzyme. Furthermore, Southern blot analysis with somatic cell hybrids showed that the PBGD gene moved to the 14q+chromosome, which confirmed PBGD to be more distal to the centromere than the rck locus. These data allowed us to construct the following order of genes: 11 cen-q23-CD3-rck-PBGD-THY1/ETS1. In this study, three infantile leukemia cell lines with t(11;19)(q23;p13) translocation were also analyzed by pulsed-field gel electrophoresis. CD3D probe detected the rearranged bands in DNA from two of them after digestion with NotI and SacII enzymes, demonstrating that the breakpoints of both cell lines were estimated to be within 360 kilobases of CD3D.

[A case of aortitis syndrome complicated with amyloidosis, type AA]

We recently saw a patient who had aortitis syndrome associated with secondary amyloidosis. To our knowledge, she is the fourth report of this complication occurring in aortitis syndrome. In November 1985, the patient, a 18 year-old woman, was admitted to our hospital because of a high fever, back pain, abdominal pain and general fatigue. On physical examination, bruit was audible on the abdomen, bilateral radial artery was weakly palpable. Angiography showed the stenosis of bilateral carotid artery, subclavian artery, renal artery and superior mesenteric artery. From the above findings, she was diagnosed aortitis syndrome, and treatment was begun with prednisolone. However, she developed recurrently a high fever, chest pain, abdominal pain and exertional dyspnea. Laboratory findings at the active stage revealed the marked elevation of leukocytes, erythrocyte sedimentation rate and C-reactive protein. On her clinical course, the number of circulating thrombocytes was paralleled with the activity of the disease. On June 1988, she developed suddenly a high fever and severe pain of abdomen. Pathological findings of her stomach showed the deposition of amyloid protein A. Laboratory findings depicted the marked increment of thrombocytes, beta-thromboglobulin and platelet factor 4. These results suggest that circulating thrombocytes may play a role in product ion of amyloid protein.

Staurosporine, a protein kinase inhibitor, attenuates intracellular Ca(2+)-dependent contractions of strips of rabbit aorta

The protein kinase inhibitor staurosporine was found to be a potent relaxant of rabbit aortic strips contracted by various agonists. This relaxing effect was slow, long-lasting and in a non-competitive fashion against various agonists. The effect of staurosporine on the KCl-induced contraction was not altered by atropine, propranolol, theophylline or indomethacin. Staurosporine (5-200 nM) inhibited the contractile responses to prostaglandin F2 alpha (3 microM), endothelin (0.1 microM), phenylephrine (3 microM) and KCl (30 mM), with ED50 values of 10.8 +/- 0.6, 24.6 +/- 8.7, 48.8 +/- 7.0, 54.0 +/- 12.7 nM, respectively. Even in Ca(2+)-free physiological salt solution, staurosporine potently antagonized the contractile responses elicited by 10 microM prostaglandin F2 alpha and 0.1 microM endothelin; in fact it was more effective than it was in normal Ca2+ solution: ED50 of 11.3 +/- 3.8 vs. 21.0 +/- 4.4 nM (P less than 0.02), and of 10.6 +/- 3.6 vs. 24.6 +/- 4.3 nM (P less than 0.01), respectively. Thus, staurosporine has an equipotent inhibitory action on intracellular and extracellular calcium-dependent contractions of aortic tissues.

[bcl-2 gene in B cell lymphoma]

In t(14;18) lymphomas, bcl-2 gene is activated by the juxtaposition of immunoglobulin (Ig) gene. The fused bcl-2-Ig gene generates chimeric mRNAs which consist of bcl-2 at 5' side and Ig at 3' side. Chimeric mRNA does not disrupt the bcl-2 coding frame of 239 amino acid polypeptide. Activated bcl-2 gene introduced in normal B lymphoblastoid cells (LCL) demonstrated an increased cloning efficiency in soft agar but failed to confer tumorigenicity to LCLs as a single agent. bcl-2 gene rearrangement in Japaneses B cell lymphoma was studied and found that 10 out of 32 cases of follicular lymphoma (31%) and 5 out of 56 cases of diffuse lymphoma (9%) were rearranged, suggesting less frequency of B cell lymphoma, particularly follicular lymphoma in Japan is partly due to less bcl-2 involvement than American cases. Three cases out of 15 cases with bcl-2 rearrangement demonstrated a unique pattern of rearrangement. Two cases of the three were analysed and found that both cases were translocated at the later step than DH-JH joining of Ig rearrangement. Thus, bcl-2 translocation in Japanese B cell lymphomas might occur at the later stage of B cell development, when compared with that in American cases. Less involvement of bcl-2 in Japanese B cell lymphoma may be explained by low susceptibility to bcl-2 rearrangement at the step of DH-JH recombination.

[BCL-2 gene in lymphocytic malignancy]

In t(14;18) (q32;q21) lymphomas, bcl-2 gene is activated by the juxtaposition of immunoglobulin (Ig) gene. The fused bcl-2-Ig gene generates chimeric mRNAs which consist of bcl-2 at 5' portion and Ig at 3' portion. Chimeric mRNA does not disrupt the bcl-2 coding frame of 239 amino acid polypeptide. Bcl-2-Ig transgenic mice demonstrated the extended B cell survival and the follicular lymphoproliferation, but they did not develop a malignancy until 25 weeks. Ten percent of them, however, developed malignant diffuse large-cell lymphomas after a long latency. Forty percent of these malignancies demonstrated the c-myc rearrangement, indicating that multiple step changes are required for malignant transformation in bcl-2 activated cells. Study on the bcl-2 gene rearrangement in Japanese B cell lymphoma and B-CLL revealed that 10 out of 32 cases of follicular lymphoma (31%), 5 out of 56 cases of diffuse lymphoma (9%) and 2 out of 30 cases of B-CLL (7%) were rearranged. Less frequency of B cell lymphoma, particularly follicular lymphoma in Japan might be partly due to the less bcl-2 involvement than in American cases. The ratio of bcl-2 involvement in B-CLL is not significantly different between Japan and U.S.A.. bcl-2 rearrangement at 5' promoter region is noted for Japanese B-CLL which was demonstrated for American cases. The clinical application of polymerase chain reaction for bcl-2 translocation was also discussed.

Molecular cloning of the gene coding for the human T cell differentiation antigen CD7

The CD7 molecule is a differentiation antigen found on the surface of T lymphocytes and also on a very minor fraction of acute nonlymphocytic leukemia (ANLL). To study the genomic structure of the CD7 gene, two clones (SY4 and SY22) were isolated by screening a genomic library with a CD7 cDNA probe. Restriction mapping of these two phage clones showed that both overlapped each other, covering a total length of 23 kilobases (kb). Transfection of mouse L cells demonstrated that SY22 contains the gene expressing the CD7 antigen reactive with monoclonal CD7 antibody (Tp40), while SY4 does not. Subcloning of a 10.5 kb fragment from a 14.4 kb insert of SY22 contained the structural gene for the CD7 antigen. Detailed restriction mapping and partial sequence analysis revealed the CD7 gene to consist of four exons. By RNase protection assay, multiple initiation sites -122 base pairs (bp) to -38 bp from ATG translation initiation site were demonstrated. The promoter region had high G + C content and contained two SP1 binding sites (CCGCCC) and an AP2 binding site (CCCCAGGC), but lacked CAAT and TATA motifs.

Effects of HA1077, a protein kinase inhibitor, on myosin phosphorylation and tension in smooth muscle

We examined the effects of HA1077, a potent inhibitor of protein kinases in vitro, on the relationship between tension and myosin-light chain (MLC20) phosphorylation in the initial phase of contraction of the rabbit aorta. The dose-response curve of HA1077 for MLC20 phosphorylation was to the left of the tension curve produced by 40 mM K+. In contrast, the potassium dose-response (15-100 mM) curves for tension and MLC20 phosphorylation were virtually identical. The nifedipine dose-response (1-3000 nM) curves for tension and MLC20 phosphorylation after 40 mM K(+)-stimulation were much the same. HA1077 inhibited the contraction induced by 30 microM prostaglandin F2 alpha (ED50 = 50 microM). Stimulation with prostaglandin F2 alpha induced both mono (MLC-P) and diphosphorylation (MLC-P2) of MLC20. In the presence of various concentrations of HA1077 (1-300 microM), the dose-response curves for MLC-P and MLC-P2 were also to the left of the tension curve. HA1077 inhibited MLC-P2 (ED50 less than microM) more effectively than it inhibited MLC-P (ED50 = 2.1 microM). These observations indicate that the relationship between tension and MLC20 phosphorylation involves inhibition of protein kinases by HA1077. The mechanism underlying the formation of MLC-P2 induced by prostaglandin F2 alpha may differ from that underlying MLC-P formation.

Molecular cloning of the chromosomal breakpoint of a B-cell lymphoma with the t(11;14)(q23;q32) translocation

The breakpoint of t(11;14)(q23;q32) chromosome translocation in a B-cell lymphoma line, RC-K8, was cloned. Immunoglobulin heavy chain (IGH) constant gene, C gamma 2 at the 5' end, was involved in this translocation, and the DNA segment juxtaposed to the C gamma 2 was proved to be derived from chromosome 11 by somatic cell hybrid study. The normal counterpart of chromosome 11 was also isolated. With a DNA probe near the breakpoint of chromosome 11, Southern blot analysis of RC-K8 and 10 other cases with translocation involving the 11q23 region was conducted, but no rearrangement bands have been observed thus far except for RC-K8.

[The relationship between the aortic pulse wave velocity and osteoporosis in elderly women]

The relationship between arteriosclerosis and osteoporosis (OP) was assessed in 20 elderly women. The aortic pulse wave velocity (PWV) was used as the index of arteriosclerosis and bone mineral content (BM) of the vertebral body, which was measured by quantitative computed tomography, was used as an index of OP. PWV and BM showed a significant correlation with aging (PWV and age: r = 0.466, p less than 0.05, BM and age: r = -0.487, p less than 0.05). In the group in which the serum alkaline phosphatase (ALP) was higher than 180 IU/l (n = 11), there was a significant inverse correlation between PWV and BM (r = -0.728, p less than 0.02). On the other hand, there was no correlation between PWV and BM in the group in which ALP was lower than 180 IU/l (n = 9). These results suggest that in cases with OP and high levels of ALP, calcium (Ca) seems to be released from the bone system and transferred to the wall of the aorta. The mechanism and pathogenesis of this Ca transference is unknown and should be investigated.

[Lung ventilation imaging with TECHNEGAS: clinical study of lung deposition and ventilation/perfusion]

In order to optimize inhalation method for lung ventilation imaging with Tc-99m-gas (TECHNEGAS), relation between lung deposition of TECHNEGAS and inhalation method was evaluated. Submaximal inhalation with breath-holding (BH), continuous submaximal inhalation (C) and tidal inhalation (TV) were compared in 35 patients (36 studies) with various lung diseases. Mean lung deposition of TECHNEGAS was 6.6-7.4%/LD in BH group and was significantly higher than other groups of inhalation method (p less than 0.05-0.001). Lung deposition increased according to the times of inhalation in C group. TV group resulted in the lowest lung deposition which was same as 5 times of inhalation in C group. Lung/filter ratio (L/F) was highest in BH group. Image quality of TECHNEGAS was significantly better in BH group. Hot spot in central airway was seen in 15% of patients. All of them was in TV or C groups. In order to improve lung deposition and image quality of the TECHNEGAS, sufficient breath-holding was important. L/F seemed to be the index of effective inhalation of the TECHNEGAS. TV was suitable for poorly cooperative or dyspneic patients. TECHNEGAS was useful for evaluation of lung ventilation to provide good quality image with safety and simplicity.

bcl-2 translocation in Japanese B cell lymphoma: novel bcl-2 translocation with immunoglobulin heavy chain diversity segment

Breakpoints of a lymphoma case with bcl-2 gene rearrangement that did not show comigration of immunoglobulin (Ig) heavy chain joining (JH) fragment were cloned. Sequence analysis revealed that the translocation broke the 3' side of the Ig heavy chain diversity (DH) segment at the heptamer recombination signal and each end was ligated to the bcl-2 locus. Since Southern blot demonstrated that both alleles of JH were rearranged, this translocation was suggested to have occurred at the step of VH-DH, or DH-DHJH recombination, one step later than that of DH-JH recombination where the common pattern of bcl-2 rearrangement generally occurs. Cases that showed comigration with JH fragment were also studied by polymerase chain reaction with 5' bcl-2 oligomer and 3' JH consensus anti-sense oligomer since it has been demonstrated that bcl-2 translocation at the major breakpoint clustering region (mbr) in American cases clusters within an about 150 bp region in the mbr. The results demonstrated that four out of five cases studied were amplified, indicating that the same clustering mechanism exists for Japanese cases. The present study, together with our previous report on Ig kappa-bcl-2, indicated that bcl-2 translocation in Japanese B cell lymphomas might occur at a later stage of B cell development, as compared with that in American cases. Less involvement of bcl-2 in Japanese B cell lymphoma may also be in part explainable by low susceptibility to bcl-2 rearrangement at the step of DH-JH recombination.

Diphosphorylation of myosin light chain in smooth muscle cells in culture. Possible involvement of protein kinase C

Prostaglandin (PG) F2 alpha (30 microM) stimulated both monophosphorylation and diphosphorylation of myosin light chain (MLC) in a smooth muscle cell line (SM-3). The diphosphorylation was significantly decreased by treatment with the protein kinase C inhibitor staurosporine (30 nM, 30 min) from 20.1% of total MLC to 4.5%. The protein kinase C down-regulation treatment of SM-3 cells with phorbol dibutyrate suppressed to 8.7% the MLC diphosphorylation activity in the SM-3 cells. This down-regulation treatment had little effect on the monophosphorylation. We propose that the MLC diphosphorylation in PGF2 alpha-stimulated SM-3 cells in culture may be regulated through mechanisms sensitive to protein kinase C.

Alteration in the myosin phosphorylation pattern of smooth muscle by phorbol ester

Pretreatment with a high concentration of phorbol 12-myristate 13-acetate (PMA, 100 nM) increased the degree of tension and extent of myosin light chain (MLC20) phosphorylation in the K(+)-stimulated rabbit aortic artery. Pretreatment with 100 nM PMA did not alter the relationship between MLC20 phosphorylation and the tension seen with K+ stimulation in the initial phase and steady state of contraction. However, a low concentration of PMA (10 nM) potentiated only the MLC20 phosphorylation during the steady state of contraction with no effect on the tension. In contrast, the prostaglandin (PG) F2 alpha-induced tension development and the MLC20 phosphorylation were not affected by PMA pretreatment at both low and high concentrations. The inhibitory action of nifedipine on the K(+)-induced contraction was not affected by pretreatment with 100 nM PMA; the concentration producing half-maximal inhibition of nifedipine for the K(+)-induced contraction (33 nM) was the same as that of the K+ plus 100 nM PMA-induced contraction (32 nM). Our results suggest that PMA may increase the level of myosin light chain kinase-dependent MLC20 phosphorylation and the tension in the K(+)-stimulated artery, an effect which differs from that seen with increases in K+ concentrations. The regulatory mechanism for the contraction involving PGF2 alpha stimulation may differ from that seen in the case of K+ stimulation.

Evaluation of inferior mesenteric vein blood flow circulation with per-rectal administration of thallium-201 and technetium-99m pertechnetate

We administered both per-rectal thallium-201 (201Tl) and technetium-99m pertechnetate (99mTc) to patients with liver diseases in order to understand the abnormalities of inferior mesenteric vein (IMV) blood flow circulation. As 201Tl heart-to-liver uptake ratio (H:L), reflecting the degree of portal-systemic shuntings (PSS), increased, the visualization of IMV in general became poor on 99mTc scintigrams. 201Tl H:L in the group with no visualization of IMV on 99mTc scintigrams was significantly higher than in the group with clear visualization of IMV (p less than 0.001). However, there were patients who showed IMV visualization among those with high 201Tl H:L. In these patients, it was considered that IMV blood flowed in the normograde direction, escaping mainly through PSS at the upper part of the portal system, and resulting in elevated H:L. In the patients without IMV visualization, IMV blood flowed in the retrograde direction, escaping mainly through collaterals at the lower part of IMV. Inferior vena cava (IVC) was visualized on 99mTc scintigrams in some patients without IMV visualization, indicating the presence of collaterals from the distal part of IMV to IVC. Per-rectal studies using these two radiotracers can afford us useful informations on the abnormalities of IMV blood flow hemodynamics in patients with liver diseases.

Stimulus-specific patterns of myosin light chain phosphorylation in smooth muscle of rabbit thoracic artery

When the rabbit thoracic artery was stimulated with submaximal concentrations of agonist [40 mM K+, 30 microM prostaglandin F2 alpha (PGF2 alpha) or 7 microM histamine], about 90% of a maximal contraction occurred. Each agonist induced a rapid development of contraction followed by a sustained response. The maximal rate of force generation stimulated with PGF2 alpha was twice that seen with K+ or histamine. Stimulation with 40 mM K+ increased the extent of monophosphorylated 20 kDa myosin light chain (MLC-P) for up to 1 min to a maximal value of 38.8 +/- 1.0%, there was a subsequent rapid decrease and the MLC-P level remained just above the basal value for 40 min (6.8 +/- 3.0%). In the case of stimulation with 7 microM histamine, MLC-P level increased rapidly and was sustained for up to 40 min (28.0 +/- 4.9%). In contrast to the stimulation with K+ or histamine, PGF2 alpha induced both mono- and diphosphorylated MLC20 (MLC-P and MLC-P2 respectively) at a low concentration (3 microM). The monophosphorylation of MLC20 induced by 30 microM PGF2 alpha reached the maximal value of 32.8 +/- 5.2%, and was sustained for up to 40 min (15.2 +/- 5.4%). The diphosphorylation of MLC20 increased rapidly (7.4 +/- 4.0% at 5 min), then decreased to the basal value within 40 min. These results suggest that different modes of stimulation of smooth muscle contraction produce different profiles of MLC20 phosphorylation. The implications of these observations are that the diphosphorylated form, specifically induced by certain agents, may modify the mode of contraction of the aortic artery.

Genuine CD7 expression in acute leukemia and lymphoblastic lymphoma

CD7 has been used as a valuable marker for normal and malignant T cells and also for a proportion of acute nonlymphocytic leukemia (ANLL) cells. Difference in reactivity was noticed among CD7 antibodies, however, when tested against ANLL cells and myeloid/monocytoid cell lines; Tp40 antibody produced in our laboratories was not reactive with the HL-60 promyelocytic line, whereas 4A antibody was reactive, even though both detected a quite similar or an identical epitope on CD7 molecule. Preincubation of HL-60 cells with human immunoglobulin preparation clearly negated the reactivity by 4A, suggesting that 4A antibody is not reactive to CD7 itself, but it probably binds with immunoglobulin G Fc receptors expressed on HL-60 cells. Five cases of ANLL which were positive with 4A antibody were selected and tested with Tp40 antibody, and only two were found to be positive. Expression of CD7 mRNA in these two cases (but not in other cases) was also demonstrated by Northern blotting with a cDNA probe for CD7 recently cloned in our laboratories, indicating that CD7 is expressed on a certain fraction of ANLL, although the positive cases may be smaller than the reports so far appeared. A Northern blot study was also conducted with two acute lymphocytic leukemia cases and one lymphoblastic lymphoma case with CD7+, CD2-/+/-, CD5-/+/- phenotype and germline T cell receptor beta genes. CD7 mRNA is expressed in all three cases and CD3 mRNA is also observed in two cases, suggesting that these tumor cells are of T precursor origin.

[The evaluation of split renal function in the experimentally induced transient renal vein obstruction]

The split renal function was measured in order to evaluate the alteration of renal function secondary from transient renal vein obstruction. Three microcuries of I-131 Hippuran and 7 microCi of Tc-99m DTPA were injected into the femoral vein of adult male rats 30 min, 3 hr, 6 hr, 2 days and 1 week after the renal vein obstruction for 30 min. Blood samples were taken from the tail vein 5, 10, 15, 20 and 30 min after injection. Immediately after taking blood sample at 30 min, both kidneys and urinary bladder with ureters were taken. The radioactivities of Tc-99m and I-131 of these samples were measured respectively using a well type scintillation counter at the energy ranges of 140 KeV +/- 25% and 360 KeV +/- 25%. In the obstructed side, the blood clearances of I-131 Hippuran (ERPF) and Tc-99m DTPA (GFR) were decreased at 30 min and 6 hr after the release of left renal vein obstruction. Therefore the filtration fraction was not significantly changed. In conclusion, the single study using either Tc-99m DTPA or I-131 Hippuran may be enough to evaluate the alteration of split renal function in a model of renal vein obstruction, although the combined study using both agents is more preferable.

[Assessment of split renal function before and after angioplasty or bypass grafting in the patients with renovascular hypertension]

Two different methods to assess the change of split renal function following angioplasty or bypass grafting were studied in a total of 12 patients with renovascular hypertension. The studies were performed before and within seven days after the therapeutic intervention. Split effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) after injections of I-131 hippuran and Tc-99m DTPA were measured using kidney counting corrected for depth and dose, described by Schlegel and Gates. In six of 10 patients with unilateral renal artery stenosis and in two patients with bilateral renal artery stenoses (two of 4 affected kidneys), the split renal function was improved after the therapeutic intervention, in accordance with the drop in blood pressure and the reduction of plasma renin activity. The improvement in ERPF and GFR was more likely in the patients without severely reduced renal function. In such patients, the improvement in ERPF was more pronounced than that in GFR. And in two patients with functional improvement, the Captopril-induced reduction of split GFR in the affected kidney was disappeared after the intervention. Moreover, in the long-term follow-up of three patients with functional improvement, one patient showed the deterioration of split renal function suggesting the relapse of renal artery stenosis. These results suggest that the combined studies of split ERPF and GFR determinations can be useful to evaluate the therapeutic effect as well as the presence or absence of functional improvement after the intervention.

bcl-2 gene rearrangement analysis in Japanese B cell lymphoma; novel bcl-2 recombination with immunoglobulin kappa chain gene

The rearrangement of bcl-2 gene was studied in 56 Japanese B cell lymphoma cases to investigate the contribution of bcl-2 gene to lymphomagenesis in Japan. Ten out of 56 cases showed bcl-2 gene rearrangement; it was detected in only 5 out of 16 follicular lymphoma cases (31%) and in 5 out of 40 diffuse B cell lymphoma cases (13%). The incidence of bcl-2 gene involvement in Japanese follicular lymphomas was lower than those reported in the United States. This might contribute to the lower incidence of follicular lymphoma cases in Japan. Novel recombination between bcl-2 and Ig kappa genes at the 5' region of bcl-2 and J kappa 4 segment was observed in one follicular lymphoma case, suggesting that bcl-2 gene is transcriptionally activated by Ig kappa enhancer. It was also suggested that this case had originated from a more differentiated B cell than most follicular lymphomas with bcl-2-Ig H recombination.

Growth- and tumor-promoting effects of deregulated BCL2 in human B-lymphoblastoid cells

Human follicular B-cell lymphomas possess a t(14;18) that translocates a putative protooncogene, BCL2, into the immunoglobulin heavy chain locus. The normal BCL2 gene is quiescent in resting B cells, expressed in proliferating, but down-regulated in differentiated B cells. Inappropriately high levels of BCL2-immunoglobulin chimeric RNA are present in t(14;18) lymphomas for their mature B-cell stage. We examined the biologic effects of BCL2 deregulation in human B cells by introducing BCL2 into human B-lymphoblastoid cell lines (LCLs) with retroviral gene transfer. Although deregulated BCL2 expression as a single agent was not sufficient to confer tumorigenicity to LCLs, it consistently produced a 3- to 4-fold increment in LCL clonogenicity in soft agar. In addition, BCL2 deregulation complements the transforming effects of the MYC oncogene in LCLs. BCL2 augmented the clonogenicity of LCLs bearing exogenous MYC and increased the frequency and shortened the latency of tumor induction in immunodeficient mice. These results demonstrate a role for BCL2 as a protooncogene that affects B-cell growth and enhances B-cell neoplasia.

[Angiotensin II-induced hypertension chemotherapy of bone and soft-tissue sarcomas]

We treated 14 patients with high grade sarcomas by angiotensin II-induced hypertension chemotherapy. The chemotherapy protocol described by Rosen was selected according to histological classification of sarcomas (small cell sarcoma, spindle cell sarcoma, pleomorphic sarcoma). The level of angiotensin-induced hypertension was one and half times as high as blood pressure at rest. Induced hypertension was maintained for 30-60 minutes. In three cases of 5 primary osteosarcomas, induced hypertension resulted in the increase of tumor stain and/or vascularity angiographically, and chemotherapeutic effects were CR or PR. The six cases with soft-tissue sarcomas were 2 cases each of CR, PR, and NC. The decrease of relative tumor blood flow under the condition of angiotensin II-induced hypertension was detected in 5 cases of 6 soft-tissue sarcomas by 133Xe clearance method. In the case of rhabdomyosarcoma, the decrease of tumor stain and vascularity by induced hypertension was observed on angiogram. As the side effects accompanying induced hypertension, nausea and chest oppression were noted in 2 cases, respectively. In this study it was suggested that angiotensin II-induced hypertension chemotherapy was effective for osteosarcoma, but that it might be ineffective for soft-tissue sarcomas.

GaAs/AlGaAs integrated-optic wavelength demultiplexer

An integrated-optic dual-channel wavelength (de)multiplexer is demonstrated on a GaAs/AlGaAs heterostructure. The device, an asymmetric Mach-Zehnder interferometer, operates with a channel separation of 19 nm in the 1500-nm-wavelength range.

Role of the macrophage in the pathogenesis of experimental autoimmune myasthenia gravis

To clarify the role of Ia antigen positive macrophages which invade motor end-plates in the induction of the chronic phase, experimental autoimmune myasthenia gravis (EAMG) rats were injected intraperitoneally with silica dust on day 6 after immunization. Silica injection partially inhibited the invasion of motor end-plates with macrophages as compared with a saline injection. The titer of antibodies to the Narke acetylcholine receptor (AChR) in the chronic phase did not differ in either the saline or the silica groups, while the titer of antibodies to rat-AChR (non-crossreactive antibodies) was lower in the silica group than in the saline group. The silica group survived longer than the saline group. These results suggest that Ia antigen positive macrophages in the acute phase act as antigen-presenting cells and play an important role in the production of antibodies to self-AChR in the chronic phase.

Thermostable DNA polymerase chain amplification of t(14;18) chromosome breakpoints and detection of minimal residual disease

Achieving the capacity to detect minimal numbers of neoplastic cells is a major cancer diagnostic challenge. Chromosomal translocations such as the t(14;18)(q32;q21) found in follicular and some nonfollicular lymphomas provide a tumor-specific molecular marker. The 14;18 breakpoints are focused at one of six immunoglobulin heavy chain joining (JH) regions on chromosome 14 and a small major breakpoint region (MBR) of the BCL2 gene on chromosome 18. We utilized universal oligonucleotide primers of a region 5' to the BCL2 MBR and at the 3' end of JH segments to initiate a DNA polymerase chain reaction that amplified these BCL2-JH junctures. Use of thermostable DNA polymerase enabled annealing and synthesis steps at temperatures approaching the melting point of the primers, providing a sensitive and specific assay capable of detecting 1 lymphoma cell in 10(6) normal cells. This technique identified the subclinical presence of leukemic cells in all seven patients examined, including two in clinical remission. It also assessed the effectiveness of protocols designed to purge malignant cells from marrow. Moreover, this approach enabled the rapid DNA sequencing of chromosomal breakpoints without their molecular cloning. This assay markedly refines the capacity to detect minimal residual disease and should improve the ability to determine the stage of disease, stratify treatment, and evaluate therapy.

Observation of portal circulation through superior mesenteric vein by enteric coated capsule of thallium-201

A new method of oral administration of an enteric coated capsule of 201Tl (201Tl-capsule) was developed to evaluate the portal circulation through the superior mesenteric vein (SMV). The 201Tl-capsule was not collapsed in the artificial gastric juice, whereas it melted soon after soaking in the artificial intestinal juice. In a clinical trial of 42 cases, 201Tl was satisfactory released in the duodenum in 36 cases where clear liver images were observed except in 1 patient. Heart to liver ratio (H/L) at 60 or 90 min after duodenal release of 201Tl was 0.32 +/- 0.07 (mean +/- 1 s.d.) in normal controls, 0.34 +/- 0.12 in chronic hepatitis, 0.31 +/- 0.12 in acute hepatitis, 0.45 +/- 0.13 in liver cirrhosis and 0.48 +/- 0.32 in cirrhosis with hepatocellular carcinoma. In 11 patients who had both oral and rectal studies with 201Tl, 7 showed a high H/L ratio of more than 0.8 in the rectal study but only 1 showed a similarly high ratio of 1.07 in the oral study. In the group of varied liver disorders we have studied so far, it was found that most of the SMV blood flowed into the liver and the degree of portal systemic shunting (PSS) from the SMV was much smaller compared to that from the inferior mesenteric vein. The present study with oral administration of the 201Tl-capsule was of value in understanding portal circulation through the SMV, however, this technique seemed of limited usefulness for evaluating overall pathologic PSS.

Alternative promoters and exons, somatic mutation and deregulation of the Bcl-2-Ig fusion gene in lymphoma

The most common translocation in human lymphoma, the t(14;18)(q32;q21), generates heterogeneous 4.2-7.2 kb Bcl-2-immunoglobulin (Ig) chimeric mRNAs resulting from alternative Bcl-2 5' exons and varied Ig 3' untranslated regions (UT). The normal human Bcl-2 gene has a three exon structure with an untranslated first exon, a facultative 220 bp intron I, but an enormous 370 kb intron II. S1 protection and primer extension analysis defined initiation sites in exon II associated with classic promoter elements and a decanucleotide (ATG-CAAAGCA) homologous with Ig variable region enhancers. Multiple initiation sites were also found in a GC-rich region with Sp1 binding motifs in exon I. Most t(14;18) breakpoints cluster within the 3' UT of Bcl-2 implicating that event in gene deregulation. The Bcl-2 gene introduced into the Ig constant (C gamma) locus of SU-DHL-6 displayed somatic mutation. While Bcl-2--Ig mRNAs demonstrated an unaltered 2.5 h half-life, the Bcl-2--Ig gene revealed an inappropriately high rate of transcription for a mature B-cell. This indicates the translocated Bcl-2 allele has escaped normal control mechanisms.

Expression of Bcl-2 and Bcl-2-Ig fusion transcripts in normal and neoplastic cells

We examined the expression of the Bcl-2 gene at chromosome segment 18q21, that is translocated into the Ig heavy chain gene locus in t(14;18) bearing lymphomas. Bcl-2, while B cell associated, is expressed in a variety of hematopoietic lineages including T cells. Bcl-2 mRNA levels are high during pre-B cell development, the time at which the t(14;18) translocation occurs, but are down regulated with maturation. Like certain other oncogenes, Bcl-2 is quiescent in resting B cells but up-regulated with B cell activation. Mature B cell lymphomas with a t(14;18) have log-folds more mRNA than matched counterparts without the translocation. A sensitive S1 protection assay revealed that all transcripts in t(14;18) B cells were Bcl-2-Ig fusion mRNAs and originated from the translocated allele. Thus, there is a marked deregulation of Bcl-2 when it is introduced into the Ig locus in t(14;18) lymphomas.

Mechanism of the t(14;18) chromosomal translocation: structural analysis of both derivative 14 and 18 reciprocal partners

To elucidate the mechanism of the t(14;18)(q32;q21) chromosomal translocation found in follicular lymphoma, we examined the structure of both derivative (der) chromosomal breakpoints as well as their germ-line predecessors. We noted that chromosome segment 18q21 was juxtaposed with immunoglobulin heavy (H) chain gene diversity (DH) regions on all five der(18) chromosomes we examined, and we confirmed the juncture with immunoglobulin H-chain gene joining (JH) regions on the der(14) chromosome. However, the t(14;18) was not fully reciprocal in that chromosome 14 DNA between the DH and JH regions was deleted. Furthermore, extra nucleotides, reminiscent of "N" segments, were present at the der(14) and possibly der(18) junctions. This indicates that despite the mature B-cell phenotype of follicular lymphoma, the t(14;18) occurs during attempted DH-JH joining, the earliest event in immunoglobulin rearrangement in a pre-B-cell. Our detailed analysis of the germ-line 18q21 region indicated that most breakpoints clustered within a 150-base-pair major breakpoint region. However, we found no evidence for evolutionarily conserved immunoglobulin-like recombinational signals at 18q21, arguing against a role for immunoglobulin recombinase in chromosome 18 breakage. Instead, a direct repeat duplication of chromosome 18 sequences was discovered at both chromosomal junctures, typical of the repair of a naturally occurring staggered double-stranded DNA break. These results prompt a translocation model with illegitimate pairing of a staggered double-stranded DNA break at 18q21 and an immunoglobulin endonuclease-mediated break at 14q32 and with N-segment addition, repair, and ligation to generate der(14) and der(18) chromosomes.

T cell receptor beta chain gene rearrangements in leukemias with immature T cell phenotype

The arrangements of the T cell receptor (TCR) beta genes were studied in leukemias with immature T cell phenotype. Three cases of acute lymphocytic leukemia (ALL) and one case of chronic myelocytic leukemia in blastic crisis (CML-BC), which expressed only Tp40 antigen of cluster of differentiation (CD) 7 without erythrocyte rosette receptor (E), did not show rearrangements of TCR beta chain genes. Two of 5 ALL cases which expressed an additional T cell antigen, T1 of CD5, showed rearrangements of TCR beta genes. Two cases of CML-BC expressing T1 and Tp40, however, had unrearranged TCR beta genes. The results altogether showed that a part of E- T1+ Tp40+ ALL cases is of T cell origin.

Development of multiple organ-localized autoimmune diseases in nude mice after reconstitution of T cell function by rat fetal thymus graft

Restoration of T cell function of athymic BALB/c nu/nu mice was investigated after transplantation of xenogeneic thymic rudiments from 15-d-old embryonic rats into kidney subcapsule. The rudiments developed well and formed a proper thymus structure composed of donor epithelia and host lymphocytes. Examination of antibody responses to SRBC revealed that approximately half the normal number of indirect PFCs were observed. Skin grafts from syngeneic BALB/c mice and thymic donor rat strains were accepted, whereas those from allogeneic mice and the rats of other than donor strains were vigorously rejected. Thymus-grafted nude mice under a conventional environment survived without any evident infectious diseases. Histological and immunofluorescence studies, however, showed a high incidence of multiple organ-localized autoimmune diseases in thyroid, salivary gland, stomach, adrenal, prostate, ovary, and testis in mice that produced the corresponding autoantibodies. These results together suggested that rat thymic grafts reconstituted T cell functions of nu/nu mice to a considerable degree, but that organ-localized autoimmune diseases developed, probably because certain auto-antigens of the recipients were recognized by the newly reconstituted host immunity.

Effector mechanism in antitumor activity of monoclonal antibodies produced against an ascitic mouse mammary tumor

Therapeutic effects of monoclonal antibodies with different immunoglobulin classes, detecting the same antigenic determinant of tumor specific antigen expressed on ascitic mouse mammary tumor MM46, were examined. With i.v. administration of gamma 2a, gamma 2b, or gamma 1 antibody we were able to keep a significant proportion of mice tumor free against i.p. inoculation of 5 X 10(4) MM46 cells with doses as small as 0.5 micrograms, but with administration of mu, gamma 3, or alpha antibody we were not able to keep mice tumor free with doses up to 5 micrograms. With 200 micrograms of antibody, however, an antitumor effect was observed even with mu or gamma 3 antibody, although alpha antibody still showed no effect at all. The therapeutic effect of gamma 2a was further examined in mice challenged with an increasing dose of tumor cells, and a significant effect was demonstrated against 1 X 10(6) cells with 200 micrograms of antibody but not against 5 X 10(6) cells. To assess the effector cells in antitumor activity of antibody in vivo, a histological examination of the tumor cells treated with each class of antibody was carried out. The tumor treated by gamma 2a antibody revealed a remarkable cell infiltration consisting predominantly of mononuclear cells, whereas those treated by mu, gamma 3, or alpha antibody did not. The tumor cells treated by gamma 1 or gamma 2b antibody showed a moderate cellular reaction. Next, a Winn assay was carried out in athymic C3H/HeN-nu/nu mice using gamma 2a antibody. A significant antitumor effect was observed even in those mice, indicating that T-cells are not predominant effector cells. The role of macrophages was studied in mice treated with two macrophage toxic agents, carrageenan and silica particles. These agents were shown to reduce the antitumor effect of gamma 2a antibody in both Winn assays and therapeutic experiments. Thus, histological examination and the blocking effect of macrophage toxic agents suggested the participation of host macrophages as effector cells in antibody-mediated tumor cell suppression in vivo.