Cytomorphologic diagnosis of malignant lymphoma arising in the heart: a case report.

BACKGROUND: Primary malignant lymphoma of the heart is extremely rare. Because its clinical signs and symptoms are typically nonspecific, it is often very difficult to detect cardiac involvement while the patient is alive. We describe a case of malignant lymphoma involving predominantly the heart and pericardium and diagnosed by pericardiac effusion cytology antemortem. CASE: An 83-year-old woman presented with dyspnea on exertion. Echocardiography revealed a low-echoic tumor mass close to the right ventricular wall and massive pericardiac effusion. Diagnosis of diffuse large B-cell lymphoma was made by cytomorphologic examination and flow cytometry of the tumor cells obtained from the effusion. Although chemotherapy was instituted immediately, the patient died of progressive heart failure. Diffuse large B-cell lymphoma predominantly involving the intracardiovascular region was confirmed at autopsy. CONCLUSION: From the experience in this case, we conclude that cytopathologic examination of sonographically guided aspiration of the cardiovascular region is very useful for antemortem diagnosis of primary malignant lymphoma of the heart.

Immunoglobulin heavy chain variable region (VH) genes of B cell chronic lymphocytic leukemia cells from lymph nodes show somatic mutations and intraclonal diversity irrespective of follicular dendritic cell network.

We analyzed the immunoglobulin heavy chain variable region (VH) gene in 4 Japanese cases of B cell chronic lymphocytic leukemia (B-CLL) with enlarged lymph nodes to clarify the presence of somatic mutations and intraclonal diversity. We also attempted to determine the role of the follicular dendritic cell (FDC) network in some proliferation centers, where tumor cells are mitotically active. Immunohistochemical studies revealed that all 4 cases showed the typical immunophenotype: CD5+, CD23+, IgM+ and IgD+. DNA was extracted from paraffin sections (lymph node) and rearranged VH gene was amplified by PCR. All but one exhibited a moderate number of somatic mutations, with percentages ranging from 4.1 to 9.5, and one of which indicated the effect of antigen selection on its VH gene. Multiple clone analysis of whole tissues showed intraclonal diversity in one case, whose VH gene carried a somatic mutation but the effect of antigen selection was not apparent. We further examined microdissected tissues to elucidate the relationship between FDC network and VH gene status in 2 cases. In one case, intraclonal diversity was not apparent irrespective of FDC network, however, both tumor cells around the FDC network and those apart from the FDC showed signs of intraclonal diversity in another case, suggesting that intraclonal diversity was not related to the FDC network in B-CLL. Here we demonstrate that some cases of B-CLL involved in lymph node carried mutated VH genes and showed intraclonal diversity like the tumor cells in the peripheral blood. However, the significance of the FDC network in the proliferation center still remains to be resolved.

Direct-antiglobulin-test-negative immune haemolytic anaemia and thrombocytopenia in a patient with Hodgkin's disease.

A case of direct-antiglobulin-test (DAT)-negative auto-immune haemolytic anaemia (AIHA) and immune thrombocytopenia (ITP) associated with Hodgkin's disease (HD) is reported. A 52-year-old male was admitted with anaemia, thrombocytopenia, and lymphadenopathy. The patient was DAT negative, although he exhibited the clinical features of warm-type AIHA and elevated levels of red-blood-cell-associated IgG (RBC-IgG). The serum level of platelet-associated IgG (PA-IgG) was markedly increased. A biopsy specimen of the inguinal lymph nodes showed HD of mixed cellularity. Marked improvement of subjective symptoms, normalization of haematological values and a decrease in the level of both RBC- and PA-IgG were observed after the start of combination chemotherapy for HD. Although the association of HD, ITP, and/or AIHA has been infrequently reported, the measurement of RBC-IgG is recommended in cases of HD with anaemia even though DAT is negative, since HD is known to be associated with various protean immunological abnormalities.

Primary central nervous system lymphomas express Vh genes with intermediate to high somatic mutations.

Primary central nervous system lymphoma (PCNSL) is a rare disease, especially among non-AIDS patients. Although almost all PCNSLs belong to the diffuse large B-cell lymphoma (DLBL) category, its clinical course differs from that of other types of DLBL. To elucidate the histogenesis of PCNSL, we analyzed the source of the cells from its variable region (VH) sequences using the polymerase chain reaction (PCR) method to amplify the immunoglobulin heavy chain (IgH) gene of DNA extracted from paraffin sections. Fifteen patients with AIDS-unrelated PCNSL of DLBL type, (7 males and 8 females), were evaluated. Only one case showed positive evidence of EBV infection. The prognosis was very poor with a median survival of 9 months. Analysis of the VH sequences revealed that the VH4 family was used in 4 cases and the VH3 family in 2 cases. The homology with previously published germline sequences was random, ranging from 82.7-93.2%, showing intermediate to high somatic mutations. In 3 of 6 cases, the existence of intraclonal diversity was suspected. These findings suggest that PCNSLs are histogenetically derived from antigen selected B cells in the germinal center (GC) environment.

Blastic natural killer cell lymphoma arising from the mediastinum with terminal deoxynucleotidyl transferase expression.

Blastic natural killer (NK) cell lymphoma/leukemia is a relatively rare NK cell malignancy. We report the second case of blastic NK cell lymphoma arising from the mediastinum with an aggressive clinical course. The patient was a 63-year-old Japanese man with an anterior mediastinum tumor. The biopsy specimen showed diffuse proliferation of tumor cells with frequent mitotic figures and apoptotic bodies. Both angiocentric features and small foci of coagulative necrosis were found in this section. The tumor cells had medium to large nuclei with a fine chromatin pattern, inconspicuous nucleoli and scanty cytoplasm. The nuclear contour was oval to moderately irregular, showing slight pleomorphism as compared with typical lymphoblastic lymphoma. The tumor cells were positive for CD2, CD56 and terminal deoxynucleotidyl transferase, but negative for other T-cell antigens, B-cell antigens and myeloid markers. In situ hybridization for Epstein-Barr virus encoded small ribonucleic acid 1 was negative.

Aberrant expression of immunoglobulin heavy chain genes in Epstein-Barr virus-negative, human immunodeficiency virus-related lymphoid interstitial pneumonia.

The two-step polymerase chain reaction (PCR) and sequencing analysis was used to analyze the immunoglobulin heavy chain variable (Ig V(H)) genes of open-chest biopsy or autopsy samples from five patients with Epstein-Barr virus-negative human immunodeficiency virus (HIV)-related lymphoid interstitial pneumonia (LIP), and the results were compared with those for Ig V(H) genes from five HIV-negative LIP patients. The findings of this study are consistent with the different immunological situations of HIV-related and HIV-negative LIP. (a) The Ig V(H)3 subgroup was underexpressed in three of five cases of HIV-related LIP. In contrast, none of the HIV-negative cases showed this abnormality. Because the Ig V(H)3 subgroup encodes the largest portion of Ig V(H) genes, a depletion of B cells expressing Ig V(H)3 genes reflects a major alteration in the B-cell compartment. (b) All HIV-related LIP cases demonstrated two or three oligoclonal populations. HIV-negative cases showed minor monoclonal or polyclonal populations, but not oligoclonal ones. These oligoclonal populations suggest the coexistence of several occult clonal B-cell populations in HIV-related LIP. (c) Some oligoclonal clones in HIV-related LIP showed mutated framework regions not demonstrated in HIV-negative clones. This degree of variation exceeds the usual mutation rate for frameworks, suggesting a role for framework residues in antigen binding. (d) The frequency of D-D fusions of minor oligoclonal clones (HIV-related LIP) is higher than that of minor monoclonal clones (HIV-negative LIP). Such D-D fusions may enhance the probability of expression of antibodies capable of binding HIV glycoproteins.

Expression of cell cycle regulating proteins in an unusual transformation of mantle cell lymphoma.

We describe here two patients with mantle cell lymphoma (MCL) who after a few years, developed to the diffuse large cell lymphoma (DLCL) (anaplastic centrocytic lymphoma) growing in a diffuse sheets without the classical MCL component. In both the initial and second biopsy specimens, in each case, tumor cells were positive for cyclin D1, sIgM, sIgD, and CD5, but were negative for CD10 and CD23. In a study of immunoglobulin heavy chain (IgH) gene rearrangement, using the polymerase chain reaction (PCR) method, the products obtained from each paired biopsy tissue sample were the same size, and in one case had an identical sequence to the non-mutated VH gene. Immunohistochemistry was used to examine the expression of p53, p27Kip1 and cyclin E. Interestingly, there was clear overexpression of p53 protein in case 1 but not in case 2, compared with other typical MCL cases. The expression of p27Kip1 in the second biopsies of each case was decreased compared with those in the initial biopsies. In case 2, however, p27Kip1 was clearly expressed in the first and second biopsies, in contrast to other typical MCL cases. Thus these 2 cases demonstrate not only that the variant form of MCL may arise de novo, but also that MCL may transform to DLCL at the time of relapse. Although the mechanism of tumor progression/transformation is still poorly understood, the overexpression of p53 or p27Kip1 may be linked to a cellular mechanism involved in the development of the variant form of MCL.

Diffuse large B cell lymphoma expressing the natural killer cell marker CD56.

The expression of the natural killer (NK) cell antigen, CD56, in hematological malignancies is rare. However, there are several reports that some hematological malignancies, such as T/NK cell lymphoma, multiple myeloma (MM) and acute myeloid leukemia (AML), express this molecule. In B cell non-Hodgkin's lymphomas (NHL), however, very limited number of cases have been reported to express CD56 molecule. Although one study has recently described that half of microvillous B cell lymphoma (MVL), an uncommon subset of large cell lymphoma, expressed CD56, there have been no reports about most common type of B-NHL, diffuse large B cell lymphoma (DLBL) other than a mention of weak CD56 expression in one of 83 DLBL. We herein presented the first case of diffuse large B cell lymphoma expressing CD56 clearly. The immunophenotype determined by immunostaining and flow cytometric analysis was CD10+, CD19+, CD20+, CD45RO-, CD3- and CD56+. On immunohistochemical study, neither bcl-2 nor TIA-1 was positive for tumor cell. Monoclonal immunoglobulin heavy chain (IgH) gene rearrangement was detected, and the sequence analysis of the variable region of IgH (VH) suggested that this tumor was derived from antigen selected post germinal center B cell. Conventional combination chemotherapy (CHOP) was administered, and the patient has still been in complete remission for 10 months.

CDR3 sequences of MALT lymphoma show homology with those of autoreactive B-cell lines.

We have examined the CDR3 sequence and adjacent regions of immunoglobulin genes from B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Twenty-nine sequences (15 sequences from 13 low-grade MALT lymphomas, marginal zone B-cell lymphomas; 7 sequences from 6 high-grade MALT lymphomas; 7 sequences from 7 diffuse large cell lymphomas) were obtained after cloning of the polymerase chain reaction-amplified segments. In the low-grade MALT, high-grade MALT and diffuse large cell lymphomas, the mean length of the CDR3 region was 47.6+/-10.31 (range 21 to 60), 38.71+/-10.37 (range 27 to 57) and 40.86+/-3.34 (range 39 to 48) nucleotides, respectively. The length of the CDR3 region was significantly greater in the low-grade MALT lymphoma group than in the other two groups. CDR3 sequences in lymphoma cell clones of 14 cases showed 60 to 81% homology with autoantibody-associated lymphocyte clones including rheumatoid factor. The incidences of these autoantibody-associated lymphocyte clones were higher in the high-grade MALT (4/6) and diffuse large lymphomas (5/7) than in the low-grade MALT lymphoma (5/13). Cases with more than 70% homology at the nucleotide level were found to have 71 to 82% homology with autoantibodies at the protein level in the low-grade MALT lymphomas (2/13), and 67% homology in the high-grade MALT lymphomas (2/7). These results indicate that MALT lymphomas may be derived from the malignant transformation of autoreactive B-cells.

Clinicopathological evaluation of the Revised European-American Classification of Lymphoid Neoplasms (REAL) in Japan.

After the publication of a Revised European-American Classification of Lymphoid Neoplasms (REAL classification) in 1994, there have been reports from Europe and America regarding its practical utility and clinical significance. However, no studies have been published from Eastern countries including Japan. It has been well recognized that the distribution of malignant lymphoma in Japan is quite different from that seen in Western countries. In addition, some new entities have also been described in the REAL classification. Therefore, it seems important to examine its practical utility and clinical significance in Japan. Of the 579 cases reviewed, approximately 68% were B-cell non-Hodgkin's lymphoma (NHL) followed by 27% T-cell lymphomas. Hodgkin's disease (HD) comprised only 5% of all cases, making the ratio of NHL to HD 20.6. The most common type was diffuse large B-cell lymphoma which represented about 37% of all cases. Peripheral T-cell lymphomas, unspecified (PTCL), occurred in 15% whereas marginal zone B-cell lymphoma followed (14.9%). However, follicle center lymphoma (FCL) was less common (4.4%) as has been previously reported. We evaluated the clinical significance of the new REAL classification in 244 cases. International Prognostic Index (IPI) was a powerful predictor of survival (p<0.0001), and the immunophenotype was significant (p<0.05). Furthermore, here, we also attempt to establish a prognostic scheme based on the histologic type. In conclusion, the REAL classification appears to be useful and clinically significant in Japan.

Expression of Cell Cycle Regulating Proteins in an Unusual Transformation of Mantle Cell Lymphoma.

We describe here two patients with mantle cell lymphoma (MCL) who after a few years, developed to the diffuse large cell lymphoma (DLCL)( anaplastic centrocytic lymphoma) growing in a diffuse sheets without the classical MCL component. In both the initial and second biopsy specimens, in each case, tumor cells were positive for cyclin D1, sIgM, sIgD, and CD5, but were negative for CD10 and CD23. In a study of immunoglobulin heavy chain (IgH) gene rearrangement, using the polymerase chain reaction (PCR) method, the products obtained from each paired biopsy tissue sample were the same size, and in one case had an identical sequence to the non-mutated VH gene. Immunohistochemistry was used to examine the expression of p53, p27(Kip1) and cyclin E. Interestingly, there was clear overexpression of p53 protein in case 1 but not in case 2, compared with other typical MCL cases. The expression of p27(Kip1) in the second biopsies of each case was decreased compared with those in the initial biopsies. In case 2, however, p27(Kip1) was clearly expressed in the first and second biopsies, in contrast to other typical MCL cases. Thus these 2 cases demonstrate not only that the variant form of MCL may arise de novo, but also that MCL may transform to DLCL at the time of relapse. Although the mechanism of tumor progression/transformation is still poorly understood, the overexpression of p53 or p27(Kip1) may be linked to a cellular mechanism involved in the development of the variant form of MCL.

Low-grade pulmonary mucosa-associated lymphoid tissue lymphoma with or without intraclonal variation.

We examined the immunoglobulin heavy chain variable (Ig VH) region genes of 11 low-grade pulmonary mucosa-associated lymphoid tissue (MALT) lymphomas by a two-step polymerase chain reaction (PCR) and sequencing analysis. We observed frequent somatic mutations with the positive selective pressure of the rearranged Ig VH genes in all cases, indicative of postgerminal center cell origin. Eight cases demonstrated intraclonal variations (hypermutation with intraclonal variation type), but the other cases showed only one major clone without intraclonal heterogeneity (hypermutation without intraclonal variation type). The former might reflect the reentry of marginal zone B cells into a germinal center environment leading to further mutations. The latter might be no longer susceptible to hypermutation mechanisms and seemed to be stable. Four cases used Ig VH genes (hv3019b9, VH26, and VH4.21), which are frequently found in a variety of autoantibodies, such as cold agglutinins, rheumatoid factors, and anti-DNA antibodies.

Role of p27Kip1 and cyclin-dependent kinase 2 in the proliferation of non-small cell lung cancer.

The cell cycle is governed by a family of cyclin-dependent kinases (Cdks). Cdk2 forms a functional complex with cyclin E and plays a pivotal role in the regulation of G1/S transition. Cdk2 activity is negatively regulated by interactions with inhibitors. p27Kip1, one of the most potent inhibitors of Cdk2, was recently identified as a powerful negative prognostic marker in non-small cell lung cancer as well as in colorectal and breast cancer. In the present study, the expression of p27 and Ki-67 antigen in nonneoplastic and cancerous lung tissues was determined by immunohistochemistry. After establishing that the antibody-measured p27 labeling index was a good reflection of the level of p27 expression measured by Western blotting, we show that p27 labeling index is decreased in cancerous lung tissues, compared with nonneoplastic lung tissues, and exhibits a significant inverse relation to the proliferation marker Ki-67 antigen, detected with monoclonal antibody MIB-1. Consistent with these data, all cancerous lung tissues showed enhanced degradation activity of p27 compared with nonneoplastic lung tissues and, in addition, increased levels of the phosphorylated form of Cdk2, as determined with Western blot analysis. The H1 histone kinase activity associated with Cdk2 was also increased in non-small cell lung cancers. Statistical analysis showed that proliferative activity as measured by MIB-1 labeling index was highly correlated with Cdk2 activity (r = 0.767, P < 0.0015). These results suggest that p27 and Cdk2 may play an important role in the proliferation of non-small cell cancer.

[A case of marginal zone B-cell lymphoma].

A 60-year-old woman had an abnormal shadow in the right lower lung field on chest roentgenogram. Transbronchial lung biopsy revealed findings consistent with malignant lymphoma, and a right middle lobectomy was performed. Pathological findings showed that tumor cells had infiltrated the epithelium, forming so-called lymphoepithelial lesions. Flow cytometric analysis of the resected specimen revealed that B-cell associated antigens (CD 19, 20) were expressed, and that the tumor cells were CD 5-, CD 10-. A marked increase in the number of lymphocytes with an IgM kappa component suggested monoclonal origin for the tumor cells in the resected specimen. Southern blot analysis showed clonal rearrangement of the heavy chain of the immunoglobulin gene. A diagnosis of malignant lymphoma of bronchus-associated lymphoid tissue was made. This tumor was defined according to the revised European. American classification of lymphoid neoplasms as a marginal zone B-cell lymphoma.

Alleviation of monocrotaline-induced pulmonary hypertension by antibodies to monocyte chemotactic and activating factor/monocyte chemoattractant protein-1.

Administration of monocrotaline (MCT) causes pulmonary vascular lesions consisting of monocyte/macrophage infiltration in the early phase and medial thickening in pulmonary arteries and arterioles associated with pulmonary hypertension (PH) in the later phase. However, the molecular mechanism of monocyte/macrophage infiltration and its roles remain elusive. Herein, we have evaluated the role of a potent monocyte chemotactic and activating chemokine/monocyte chemoattractant protein-1 (MCAF/MCP-1) in MCT-induced PH in rats. A single injection of MCT induced PH at Day 21, as evidenced by increases in the ratio of right ventricular to left ventricular and septum weights (RV/LV+S) and right ventricular systolic pressure (RVSP). A significant increase in macrophage number in lungs started at Day 14, reaching a maximum at Day 21. MCAF/MCP-1 levels in bronchoalveolar lavage fluids were elevated significantly at Day 14 and remained high until Day 28, whereas plasma MCAF/MCP-1 levels increased at Day 7, returning to normal levels by Day 21. Immunoreactive MCAF/MCP-1 proteins were mainly detected in macrophages in alveoli and in perivascular regions of pulmonary arterioles and venules. Intravenous administration of anti-MCAF/MCP-1 antibodies with MCT significantly decreased macrophage infiltration and eventually reduced the increases in RV/LV+S and RVSP, as well as medial thickening of pulmonary arterioles. Thus, MCAF/MCP-1 is essentially involved in MCT-induced PH by recruiting and activating macrophages.

A particular characteristic of IgH complementarity-determining region 3 suggests autoreactive B-cell origin of primary gastric B-cell lymphomas.

To clarify the origin of tumor cells and the possible role of antigen in the pathogenesis of mucosa-associated lymphoid tissue (MALT) lymphoma, we analyzed the third complementarity determining region of IgH gene in nine primary gastric B-cell lymphomas by PCR. The presence of vacA gene of Helicobacter pylori was also determined. These cases were diagnosed histopathologically as three low (extranodal marginal zone B-cell lymphoma)- and three high-grade MALT lymphomas and three diffuse large-cell lymphomas without evidence of MALT lymphoma. All cases showed a monoclonally rearranged JH band. A single dominant clone was detected by sequencing the IgH CDR3 regions in eight cases. In the remaining cases. In the remaining case, two major sequences were identified. Complementarity-determining region 3 (CDR3) sequences in lymphoma cell clones of seven cases showed 61% to 81% homology with autoantibody-associated lymphocyte clones including rheumatoid factor. The N-D-N region in the low-grade MALT lymphoma group was significantly longer than in the high-grade lymphoma groups. Although vacA gene of H. pylori was detected in five of nine cases, all lymphoma cell clones showed no association with foreign antigen. These results indicate that autoantigen may be responsible for the clonal selection of lymphoma cells, and thus autoimmunity may play a role in the pathogenesis of primary gastric B-cell lymphomas.

Proliferating cell nuclear antigen in hypertrophied spinal ligaments. Immunohistochemical localization of proliferating cell nuclear antigen in hypertrophied posterior longitudinal ligament of the cervical spine.

STUDY DESIGN: An experimental immunohistochemical investigation using an antibody for proliferating cell nuclear antigen. Surgically-extirpated specimens of posterior longitudinal ligament tissues from patients with hypertrophy of the posterior longitudinal ligament and other disorders of the cervical spine were analyzed. OBJECTIVE: To analyze the developmental mechanism of hypertrophy of the posterior longitudinal ligament, the authors evaluated the growth activity of cells in the posterior longitudinal ligament tissues by examining the immunolocalization of the proliferating cell nuclear antigen. SUMMARY OF BACKGROUND DATA: Although a number of cases of hypertrophy of the posterior longitudinal ligament have been reported, the pathophysiology of ligament hypertrophy is still unclear. It is well established that the proliferating cell nuclear antigen is a cell proliferation marker, and immunohistochemical analysis using an anti-proliferating cell nuclear antigen antibody is of value in assessing the cell growth activity of several tissues. METHODS: During anterior decompression surgery in the cervical spine, the authors extirpated posterior longitudinal ligament tissues in one piece from patients with hypertrophy of the posterior longitudinal ligament, ossification of the posterior longitudinal ligament, cervical disc herniation, and cervical spondylotic myelopathy. Midsagittal sections of the specimens were stained with an antibody against the proliferating cell nuclear antigen. RESULTS: In cases of hypertrophy of the posterior longitudinal ligament, immunostaining with the proliferating cell nuclear antigen was detected in cells in the posterior longitudinal ligament, not only at the vertebral endplate level, but also at the midvertebral level. A similar distribution of proliferating cell nuclear antigen-positive cells was observed in cases of ossification of the posterior longitudinal ligament. In cases of cervical disc herniation, however, proliferating cell nuclear antigen-positive cells in posterior longitudinal ligament tissues were restricted to the vertebral endplate level. No immunostaining with the proliferating cell nuclear antigen was seen in posterior longitudinal ligament tissues in cases of cervical spondylotic myelopathy. CONCLUSIONS: Cell growth activity was accelerated in posterior longitudinal ligament tissues in cases of hypertrophy of the posterior longitudinal ligament; such an unusual phenotype of posterior longitudinal ligament cells was also expressed in cases of ossification of cervical disc herniation and cervical spondylotic myelopathy. Therefore, up-regulation of the growth of posterior longitudinal ligament cells may contribute to the development of hypertrophy of the posterior longitudinal ligament, and some common regulatory mechanism(s) on the proliferation of posterior longitudinal ligament cells seem to underlie the development of hypertrophy of the posterior longitudinal ligament and ossification of the posterior longitudinal ligament.

[A case of thymic carcinoma producing granulocyte colony-stimulating factor].

A 73-year-old man was admitted complaining of chest pain and weight loss. A chest X-ray film and chest CT scan showed a tumorous mass in the anterior mediastinum with moderate pleural effusion. Percutaneous needle biopsy specimens from the mass resulted in a diagnosis of poorly differentiated squamous cell carcinoma of the thymus. Laboratory findings on admission showed marked leukocytosis with no evidence of infection or bone marrow metastasis. The level of serum granulocyte colony-stimulating factor (G-CSF) was abnormally high (79.2 pg/ml, normal < 30). Carcinoma cells in the specimen showed positive staining with anti G-CSF monoclonal antibody, thus indicating that they produced G-CSF. Because multiple metastatic lesions on the chest wall and liver were detected, we performed combination chemotherapy with cisplatin, vindesine and mitomycin C. After 2 courses of chemotherapy, a decrease in tumor size was verified by CT scan. As the tumor size decreased, the patients white blood cell count and serum G-CSF concentration fell to normal levels.

Interleukin-11 Gene Expression in Human Lymphoid Malignancy.

Interleukin-11 (IL-11) has diverse biological effects in hematopoiesis has been shown to share important functions with IL-6. However, unlike IL-6, there has been little information about the expression of IL-11 in lymphoid malignancy. Using reverse transcriptase polymerase chain reaction, IL-11 transcript was found in a number of lymphoid cell lines. A high level of expression was found in follicular lymphoma cell line FL18, and this was also detectable by Northern blotting. When TPA/A23187 were added to the culture of bone marrow stromal cell line KM102, IL-11 transcripts were rapidly upregulated. In contrast, levels of IL-11 transcripts were not increased in FL18 even upon the stimulation. The addition of actinomycin D to the cultures showed that the half life of the transcripts was similar in both FL18 and KM102. This suggests that posttran scriptional processes might not be involved in the constitutive expression of FL18. The results of IL-11 bioassay and enzymed-linked immunosorbent assay showed that FL18 did not secrete biologically active IL-11 into the medium. IL-11 transcript was also found in lymphoma cells in patient with malignant lymphoma, but not in B and T lymphocytes from reactive hyperplasia. Our results indicate that IL-11 transcripts can sometimes be produced in the neoplastic transformation of lymphoid cells.

12-O-tetradecanoylphorbol-13-acetate (TPA) downregulates expression of CD30 in erythroleukemia cell line K562.

CD30, a member of the tumour necrosis factor/nerve growth factor receptor superfamily, has been thought to have pleiotropic functions on immune response. However, there has been only a little information about the mechanism of CD30 expression. In this study, modulation of the CD30 molecule was investigated by the treatment with 12-O-tetradecanoyl-phorbol-13-acetate (TPA). When cultures were supplemented with TPA, CD30 transcript was downregulated in a dose- and time-dependent manner in the erythroleukemia cell line K562. Half reduction of CD30 transcript, precursor protein and surface protein was at 3 h, 6 h, and 40 h, respectively, by Northern blot and Western blot analyses. This consecutive reduction of both the transcript and proteins suggests that TPA directly inhibits the transcriptional step of CD30, and subsequently CD30 molecules would decrease on the cell surface. To determine whether the protein kinase C (PKC) pathway is involved in this reduction, a PKC inhibitor, 10 microM H-7, was added to the K562 culture. The addition of H-7 recovered the inhibitory effect of TPA, indicating that PKC is involved in the transcription of CD30. When either 2 micrograms/ml actinomycin D or 20 micrograms/ml cycloheximide was added simultaneously with TPA to the culture, the repressive effect of TPA on CD30 was abolished. These results showed that the repression would also partly involve ongoing mRNA and protein synthesis under TPA treatment.