FDG-PET in T-cell and NK-cell neoplasms

BACKGROUND

A growing number of studies demonstrate the utility of (18)fluoro-2-deoxyglucose positron emission tomography (FDG-PET) in the management of malignant lymphoma. The results of FDG-PET, however, have not been studied extensively for T-cell and natural killer (NK)-cell neoplasms.

PATIENTS AND METHODS

We retrospectively evaluated pretreatment FDG-PET scans in 41 patients with T/NK-cell neoplasms diagnosed according to the World Health Organization (WHO) classification. Histological subtypes frequently included were peripheral T-cell lymphoma, unspecified (PTCLu, n = 11), extranodal NK/T-cell lymphoma, nasal type (ENKL, n = 8), primary cutaneous anaplastic large cell lymphoma (C-ALCL, n = 5), and angioimmunoblastic T-cell lymphoma (AILT, n = 4).

RESULTS

FDG-PET detected a lymphoma lesion in at least one site in 36 out of 41 patients. The positive rate was equally high in most histological subtypes except for cutaneous lymphomas: PTCLu 91%, ENKL 100%, C-ALCL 60%, AILT 100%. All the patients without an FDG-avid lesion had lesions restricted to skin. Among patients who had cutaneous lesions, only 50% had FDG-avid cutaneous lesions, all of which were tumorous. The positive rate of FDG-PET for bone marrow involvement was only 20%.

CONCLUSION

T/NK-cell neoplasms incorporated in this study were generally FDG-avid except for cutaneous lesions and bone marrow involvement.

A high incidence of late-onset neutropenia following rituximab-containing chemotherapy as a primary treatment of CD20-positive B-cell lymphoma: a single-institution study

BACKGROUND

Late-onset neutropenia (LON) has been reported following rituximab-containing chemotherapy. Its incidence and risk factors, however, have not been extensively studied.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of 107 patients treated with rituximab-containing chemotherapy as a primary treatment of CD20-positive B-cell lymphomas and identified cases with LON as defined by the neutrophil count of <or=1.0 x 10(9)/l without an apparent cause after the recovery of neutrophil count following completion of the intended chemotherapy.

RESULTS

With a median follow-up of 411 days, 23 patients developed LON out of the 107 at a median of 106 days after the last chemotherapy. Cumulative incidence of LON among the total patients was 24.9%. The median neutrophil count nadir was 0.61 x 10(9)/l. The LON episodes were generally self-limited, and filgrastim was administered in one patient. Including this patient, there were no serious infectious episodes in the cases with LON. In multivariate analysis, intensive chemotherapy regimens including high-dose therapy followed by autologous hematopoietic stem cell transplantation (ASCT) and high-dose methotrexate-containing regimens without ASCT were a risk factor for LON.

CONCLUSION

This study suggests that LON is a frequent complication of rituximab-containing intensive chemotherapy.

High-grade cytomegalovirus antigenemia after hematopoietic stem cell transplantation

Clinical impact of high-grade (HG) cytomegalovirus (CMV) antigenemia after hematopoietic stem cell transplantation has not been clarified. Therefore, in order to investigate the risk factors and outcome for HG-CMV antigenemia, we retrospectively analyzed the records of 154 Japanese adult patients who underwent allogeneic hematopoietic stem cell transplantation for the first time from 1995 to 2002 at the University of Tokyo Hospital. Among 107 patients who developed positive CMV antigenemia at any level, 74 received risk-adapted preemptive therapy with ganciclovir (GCV), and 17 of these developed HG-antigenemia defined as > or = 50 positive cells per two slides. The use of systemic corticosteroids at > or = 0.5 mg/kg/day at the initiation of GCV was identified as an independent significant risk factor for HG-antigenemia. Seven of the 17 HG-antigenemia patients developed CMV disease, with a cumulative incidence of 49.5%, which was significantly higher than that in the low-grade antigenemia patients (4%, P<0.001). However, overall survival was almost equivalent in the two groups. In conclusion, the development of HG-antigenemia appeared to depend on the profound immune suppression of the recipient. Although CMV disease frequently developed in HG-antigenemia patients, antiviral therapy could prevent a fatal outcome.

Cardiac complications after haploidentical HLA-mismatched hematopoietic stem cell transplantation using in vivo alemtuzumab

Alemtuzumab is a humanized monoclonal antibody directed against human CD52 with a strong lympholytic effect. We have performed unmanipulated hematopoietic stem cell transplantation (HSCT) from 2- or 3-locus-mismatched family donors in 14 patients using in vivo alemtuzumab. All achieved complete donor cell engraftment and grade III-IV acute graft-versus-host disease was observed in only one patient. However, eight of the 14 patients developed grade II-IV cardiac complications according to Bearman's criteria. Next, we retrospectively analyzed the records of 142 adult patients who underwent allogeneic HSCT from 1995 to 2004 to evaluate whether the use of alemtuzumab was an independent risk factor for cardiac complications. Among several factors that increased the incidence of grade II-IV cardiac complications with at least borderline significance, a multivariate analysis identified the cumulative dose of anthracyclines (P=0.0016) and the use of alemtuzumab (P=0.0001) as independent significant risk factors. All of the cardiac complications in the alemtuzumab group were successfully treated with diuretics and/or catecholamines. Patient selection and close monitoring of cardiac function may be important in HLA-mismatched HSCT using in vivo alemtuzumab.

Predictors for severe cardiac complications after hematopoietic stem cell transplantation

The value of pre-transplant factors for predicting the development of cardiac complications after transplantation has been inconsistent among studies. We analyzed the impact of pre-transplant factors on the incidence of severe cardiac complications in 164 hematopoietic stem cell transplant recipients. We identified eight patients (4.8%) who experienced grade III or IV cardiac complications according to the Bearman criteria. Seven died of cardiac causes a median of 3 days after the onset of cardiac complications. On univariate analysis, both the cumulative dose of anthracyclines and the use of anthracyclines within 60 days before transplantation affected the incidence of severe cardiac complications (P=0.0091 and 0.011). The dissociation of heart rate and body temperature, which reflects "relative tachycardia", was also associated with a higher incidence of cardiac complications (P=0.024). None of the variables obtained by electrocardiography or echocardiography were useful for predicting cardiac complications after transplantation, although the statistical power might not be sufficient to detect the usefulness of ejection fraction. On a multivariate analysis, the cumulative dose of anthracyclines was the only independent significant risk factor for severe cardiac complications. We conclude that the cumulative dose of anthracyclines is the most potent predictor of cardiac complications and the administration of anthracyclines should be avoided within two months before transplantation.

Increased incidence of acute graft-versus-host disease with the continuous infusion of cyclosporine A compared to twice-daily infusion

We retrospectively compared the incidence of acute graft-versus-host disease (GVHD) before and after September 1999, when we changed the mode of cyclosporine A (CsA) administration from twice-daily infusions (TD) (n=58) to continuous infusion (CIF) (n=71). The incidence of grade II-IV acute GVHD in the CIF group (56%) was significantly higher than that in the TD group (27%, P=0.00022). Multivariate analysis identified only two independent significant risk factors for the development of grade II-IV acute GVHD; CIF of CsA (relative risk 2.59, 95% CI 1.46-4.60, P=0.0011) and the presence of HLA mismatch (2.01, 95% CI 1.15-3.53, P=0.014). The incidence of relapse was significantly lower in the CIF group when adjusted for disease status before transplantation (0.41, 95% CI 0.18-0.95, P=0.038), which resulted in better disease-free survival in high-risk patients (43 vs 16% at 2 years, P=0.039), but not in standard-risk patients (72 vs 80%, P=0.45). CIF of CsA with a target level of 250-400 ng/ml may not be appropriate for GVHD prophylaxis in standard-risk patients.

Male predominance among Japanese adult patients with late-onset hemorrhagic cystitis after hematopoietic stem cell transplantation

Late-onset hemorrhagic cystitis (LHC) after hematopoietic stem cell transplantation (HSCT) is mainly caused by viral infections. We retrospectively analyzed the records of 141 Japanese adult patients who underwent a first allogeneic HSCT from 1995 to 2002. In all, 19 patients developed LHC a median of 51 days after HSCT. Adenovirus (AdV) was detected in the urine of 10 LHC patients, of whom eight had AdV type 11. Five of the six available serum samples from these patients were also positive for AdV type 11, but the detection of AdV in serum was not associated with a worse outcome. Male sex and the development of grade II-IV acute graft-versus-host disease were identified as independent significant risk factors for LHC. Male predominance was detected in LHC after HSCT, as has been previously shown in children with AdV-induced acute HC. The detection of AdV DNA in serum did not predict a poor outcome.

Reverse seroconversion of hepatitis B virus after hematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation in patients previously positive for hepatitis B surface antibody (HBsAb), so-called reverse seroconversion, has been considered to be a rare complication after hematopoietic stem cell transplantation (HSCT). We experienced two patients who developed reverse seroconversion among nine who were HBsAb positive and Hepatitis B core antibody (HBcAb) positive before HSCT; one after autologous bone marrow transplantation (BMT) and another after allogeneic peripheral blood stem cell transplantation (PBSCT). We reviewed the literature and considered that reverse seroconversion of HBV after HSCT is not uncommon among HBsAb positive recipients. The use of corticosteroids, the lack of HBsAb in donor, and a decrease in serum HBsAb and HBcAb levels may predict reverse seroconversion after HSCT.

Expression of p16INK4A and p14ARF in hematological malignancies

The INK4A/ARF locus yields two tumor suppressors, p16INK4A and p14ARF, and is frequently deleted in human tumors. We studied their mRNA expressions in 41 hematopoietic cell lines and in 137 patients with hematological malignancies; we used a quantitative reverse transcription-PCR assay. Normal peripheral bloods, bone marrow and lymph nodes expressed little or undetectable p16INK4A and p14ARF mRNAs, which were readily detected in 12 and 17 of 41 cell lines, respectively. Patients with hematological malignancies frequently lacked p16INK4A expression (60/137) and lost p14ARF expression less frequently (19/137, 13.9%). Almost all patients without p14ARF expression lacked p16INK4A expression, which may correspond to deletions of the INK4A/ARF locus. Undetectable p16INK4A expression with p14ARF expression in 41 patients may correspond to p16INK4A promoter methylation or to normal expression status of the p16INK4A gene. All patients with follicular lymphoma (FL), myeloma or acute myeloid leukemia (AML) expressed p14ARF while nine of 23 patients with diffuse large B cell lymphoma (DLBCL) lost p14ARF expression. Patients with ALL, AML or blast crisis of chronic myelogenous leukemia expressed abundant p16INK4A mRNAs more frequently than patients with other diseases (12/33 vs 6/104, P < 0.01). Patients with FL and high p14ARF expression had a significantly shorter survival time while survival for patients with DLBCL and increased p14ARF expression tended to be longer. These observations indicate that p16INK4A and p14ARF expression is differentially affected among hemato- logical malignancies and that not only inactivation but also increased expression may have clinical significance.

Hairy cell leukemia with translocation (11;20)(q13;q11) and overexpression of cyclin D1

We report on a male Japanese patient with hairy cell leukemia (HCL). A cytogenetic study with lipopolysaccharide stimuli showed a novel translocation (11;20)(q13;q11) in 10% of the analyzed cells. Northern blot analysis and RT-PCR analysis for cyclin D1 revealed the overexpression of cyclin D1, although the southern blot analysis of PRAD1 gene showed no rearrangement. In this particular case, the t(11;20)(q13;q11) might play some role in the oncogenesis of HCL and the overexpression of cyclin D1.

Expression of p21(Cip1/Waf1/Sdi1) and p27(Kip1) cyclin-dependent kinase inhibitors during human hematopoiesis

Expression of p21 and p27 cyclin-dependent kinase inhibitors is associated with induced differentiation and cell-cycle arrest in some hematopoietic cell lines. However, it is not clear how these inhibitors are expressed during normal hematopoiesis. We examined various human hematopoietic colonies derived from cord blood CD34(+) cells, bone marrow, and peripheral blood cells using a quantitative reverse transcription-polymerase chain reaction assay, immunochemistry, and/or Western blot analysis. p21 mRNA was expressed increasingly over time in all of the colonies examined (granulocytes, macrophages, megakaryocytes, and erythroblasts), whereas p27 mRNA levels remained low, except for erythroid bursts. Erythroid bursts expressed both p21 and p27 mRNAs with differentiation but expressed neither protein, whereas both proteins were expressed in megakaryocytes and peripheral blood monocytes. In bone marrow, p21 was immunostained almost exclusively in a subset of megakaryocytes and p27 protein was present in megakaryocytes, plasma cells, and endothelial cells. In megakaryocytes, reciprocal expression of p27 to Ki-67 was evident and an inverse relationship between p21 and Ki-67 positivities was also present, albeit less obvious. These observations suggest that a complex lineage-specific regulation is involved in p21 and p27 expression and that these inhibitors are involved in cell-cycle exit in megakaryocytes.

A new multiple myeloma cell line, MEF-1, possesses cyclin D1 overexpression and the p53 mutation

BACKGROUND

The t(11;14)(q13;q32) translocation with cyclin D1 overexpression commonly is found in multiple myeloma (MM) and in mantle cell lymphoma (MCL). Several reports have shown that p53 mutations in MCL lead to blastoid transformation and a worse prognosis; however, the role of p53 mutations in MM with t(11;14) is unclear.

METHODS

In this study the authors describe a patient with MM with t(11;14) and a p53 mutation at presentation and characterized a cell line, MEF-1, established from this patient. Immunohistochemical analysis of p53 and cyclin D1 proteins was performed. The p53 gene was analyzed by polymerase chain reaction-single strand conformation polymorphism and direct sequencing. The expression of cyclin D1 mRNA was examined by Northern blot analysis.

RESULTS

MEF-1 had t(11;14) with overexpression of cyclin D1 mRNA and produced immunoglobulin kappa-light chain. MEF-1 had a mutation in exon 7 (codon 255-257) of the p53 gene, which was noted in the patient's myeloma cells.

CONCLUSIONS

p53 mutations may be important genetic events in disease progression of MM with t(11;14). The MEF-1 cell line may be a useful tool to study mechanisms of progression in MM based on abnormalities of the cyclin D1 gene.

Growth arrest associated with 12-o-tetradecanoylphorbol-13-acetate-induced hematopoietic differentiation with a defective retinoblastoma tumor suppressor-mediated pathway

The retinoblastoma tumor suppressor (Rb) gene product plays an essential role in cell-cycle regulation. However, its role in terminal differentiation of hematopoietic cells is speculative. Here we show a model of 12-o-tetradecanoylphorbol-13-acetate (TPA)-induced hematopoietic differentiation and growth arrest with a defective Rb-mediated pathway. TPA treatment arrested the cell cycle of a human hematopoietic cell line, MEG-01s, at the G1-S boundary and induced expression of p21/SDI1/WAF1/CIP1 and p27/KIP1. Both of these proteins were present in cyclin E-associated complexes, the histone H1 and Rb kinase activities of which were then inactivated. However, MEG-01s cells lacked the intact Rb protein and the Rb-mediated pathway was defective. This model raises a question about the role for Rb in terminal differentiation of hematopoietic cells.

Cyclin D1 overexpression detected by a simple competitive reverse transcription-polymerase chain reaction assay for lymphoid malignancies

t(11;14)(q13;q32) observed in B-cell malignancies is associated with cyclin D1 (bcl-1, PRAD1, CCND1) overexpression. We devised a simple competitive reverse transcription-polymerase chain reaction (RT-PCR) assay for rapid detection of cyclin D1 overexpression. Sharing a single upstream primer derived from a homologous sequence in cyclins D1, D2 and D3, each PCR product serves as a competitor and cyclin D1 overexpression is determined by comparing the intensities of the three amplified products. We analyzed cyclin D1 in clinical specimens from 104 patients with lymphoid malignancies. Cyclin D1 overexpression was evident in 13 of 104 (7/72 non-Hodgkin's lymphomas, 0/6 adult T-cell lymphoma/leukemias, 0/4 Hodgkin's diseases, 0/11 acute lymphoblastic leukemias, 3/4 multiple myelomas, 1/2 Waldenström's macroglobulinemias, 1/2 prolymphocytic leukemias and 1/3 chronic lymphocytic leukemias). Among 72 patients for whom cytogenetic studies had been done, all 7 patients with t(11;14) were positive. The relative expression levels of D-type cyclins altered dramatically in the presence of t(11;14). Thus, this RT-PCR assay can identify tumors with cyclin D1 overexpression. Cyclin D1 overexpression was frequent in extranodal specimens (11 out of 32 vs. 2 of 72 lymph nodes) and was restricted to specific types of lymphoid malignancies, as observed using other methods. This reliable assay should be suitable to provide clinical guidance for the diagnosis and management of lymphoid malignancies, especially in the case of extranodal involvement.

[Mantle cell lymphoma with multiple extranodal involvement]

A 79-year-old male was admitted to our hospital because of general fatigue and night sweat. Physical examination showed generalized superficial lymphadenopathy, marked splenomegaly, and tumors in the conjunctiva and the abdomen. Chest X-ray and computed tomography (CT) revealed pleural effusion and intrathoracic lymphadenopathy. Abdominal ultrasonography and CT showed hepatosplenomegaly and intraperitoneal tumors. Upper gastrointestinal fiberscopy revealed multiple polypoid lesions and ulcers in the duodenum and the stomach. Involvement of relatively small-sized lymphocytes with cleaved nuclei was identified in each biopsied specimen from a cervical lymph node, a tumor in the conjunctiva, gastrointestinal polypoid lesions, and the bone marrow. Surface marker analysis of abnormal lymphocytes in the bone marrow revealed that CD5, CD19, and CD20 were strongly positive, but CD23 was weakly positive. Although (11:14)(q13:q32) translocation was not identified by chromosome analysis of bone marrow cells, Northern blot analysis of bone marrow cells revealed overexpression of the PRAD1 oncogene. Diagnosis of mantle cell lymphoma (MCL) was made. Combination chemotherapy by cyclophosphamide and vincristine was not effective, but etoposide perorally given at a dose of 50 mg per day was effective. In MCL, extranodal involvement of a digestive tract and bone marrow is well known. This case suggests that involvement of multiple organs including lacrimal glands and pleura could be characteristic of MCL cells.

Detection of cyclin D1 (bcl-1, PRAD1) overexpression by a simple competitive reverse transcription-polymerase chain reaction assay in t(11;14)(q13;q32)-bearing B-cell malignancies and/or mantle cell lymphoma

In mantle cell lymphoma, the t(11;14)(q13;q32) and its molecular counterpart, bcl-1 rearrangement, are consistent features and lead to cyclin D1 (bcl-1, PRAD1) proto-oncogene overexpression. In order to detect cyclin D1 overexpression, we developed a simple assay involving a reverse transcription followed by competitive polymerase chain reaction (PCR). A single upstream primer was derived from a homologous region between cyclin D1 and the other D-type cyclins, cyclins D2 and D3, while three downstream primers were specific to their respective D-type cyclins. Because the upstream primer was shared in PCR amplification of the three sequences, each PCR product served as a competitor and the quantification of the target was made by comparison of the intensity of the three products. With this assay we analyzed 45 hematopoietic cell lines and 40 clinical specimens. Cyclin D1 was rarely expressed in lymphoid cell lines except in t(11;14)(q13;q32)-bearing B-cell malignancies and/or mantle cell lymphoma, which expressed cyclin D1 predominantly. In myeloid cell lines, the levels of cyclin D1 expression varied and never exceeded the sum of cyclin D2 and D3 levels. Cyclin D3 was ubiquitously expressed while cyclins D1 and D2 were differentially used. The observations suggest that human cyclin D3 may play a fundamental role in hematopoiesis and that cyclins D1 and D2 may have different lineage- or differentiation-dependent functions. With this assay, small aliquots of clinical specimens such as 100 microL peripheral blood were enough to detect cyclin D1 overexpression without a well-controlled standard. The technique was validated as highly comparable with Northern analysis. This rapid and reliable detection of cyclin D1 overexpression may have practical clinical utility in the analysis and management of B-cell malignancies.

Severe hepatitis related to chemotherapy in hepatitis B virus carriers with hematologic malignancies. Survey in Japan, 1987-1991

BACKGROUND

Hepatitis B (HB) virus (HBV) infection is often reactivated, leading to severe hepatitis and death. Because the actual incidence of such complications is unknown, the authors surveyed hospitals to record the incidence of these complications and to identify clinical parameters that would possibly predict the development of hepatic complications.

METHODS

First, 250 hospitals, belonging to the Japanese Society of Clinical Hematology, were surveyed for hematologic patients with chronic hepatitis or those with asymptomatic hepatitis virus infection in whom severe hepatitis related to chemotherapy occurred between 1987 and 1991. Second, 117 hospitals that responded to the first questionnaire were surveyed for HBV carriers without severe hepatitis who were prescribed chemotherapy.

RESULTS

One-half the number of patients with severe hepatitis were HBV carriers. The incidence of severe hepatitis (52.7%) and the mortality rate (23.6%) were extremely high in HBV carriers. The incidence of severe hepatitis was significantly higher in patients with chronic hepatitis or those receiving corticosteroids (P < 0.05). The mortality rate was significantly lower in patients who were positive for hepatitis Be antigen (HBeAg) and negative for the antibody to HBeAg (anti-HBe), compared with findings in other patients (P < 0.05).

CONCLUSIONS

HBV infection is a major causal agent for severe hepatitis related to chemotherapy in Japanese individuals. Chemotherapy, including corticosteroids, to treat hematologic malignancies should be considered risky in HBV carriers, especially those with chronic hepatitis or serologies negative for HBeAg and positive for anti-HBe.

Severe hepatitis related to chemotherapy in hepatitis B virus carriers with hematologic malignancies. Survey in Japan, 1987-1991

BACKGROUND

Hepatitis B (HB) virus (HBV) infection is often reactivated, leading to severe hepatitis and death. Because the actual incidence of such complications is unknown, the authors surveyed hospitals to record the incidence of these complications and to identify clinical parameters that would possibly predict the development of hepatic complications.

METHODS

First, 250 hospitals, belonging to the Japanese Society of Clinical Hematology, were surveyed for hematologic patients with chronic hepatitis or those with asymptomatic hepatitis virus infection in whom severe hepatitis related to chemotherapy occurred between 1987 and 1991. Second, 117 hospitals that responded to the first questionnaire were surveyed for HBV carriers without severe hepatitis who were prescribed chemotherapy.

RESULTS

One-half the number of patients with severe hepatitis were HBV carriers. The incidence of severe hepatitis (52.7%) and the mortality rate (23.6%) were extremely high in HBV carriers. The incidence of severe hepatitis was significantly higher in patients with chronic hepatitis or those receiving corticosteroids (P < 0.05). The mortality rate was significantly lower in patients who were positive for hepatitis Be antigen (HBeAg) and negative for the antibody to HBeAg (anti-HBe), compared with findings in other patients (P < 0.05).

CONCLUSIONS

HBV infection is a major causal agent for severe hepatitis related to chemotherapy in Japanese individuals. Chemotherapy, including corticosteroids, to treat hematologic malignancies should be considered risky in HBV carriers, especially those with chronic hepatitis or serologies negative for HBeAg and positive for anti-HBe.

Oncogenic collaboration of the cyclin D1 (PRAD1, bcl-1) gene with a mutated p53 and an activated ras oncogene in neoplastic transformation

Cyclin D1 is one of the key regulators in G1 progression in the cell cycle and is also a candidate oncogene (termed PRAD1 or bcl-1) in several types of human tumors. We report a collaboration of the cyclin D1 gene with ras and a mutated form of p53 (p53-mt) in neoplastic transformation. Transfection of cyclin D1 alone or in combination with ras or with p53-mt was not sufficient for focus formation of rat embryonic fibroblasts. However, focus formation induced by co-transfection of ras and p53-mt was enhanced in the presence of the cyclin D1-expression plasmid. Co-transfection of ras- and p53-mt-transformants with the cyclin D1-expression plasmid resulted in reduced serum dependency in vitro. Furthermore, the transformants expressing exogenous cyclin D1 grew faster than those without the cyclin D1 plasmid when injected into nude mice. These observations strengthen the significance of cyclin D1 overexpression through gene rearrangement or gene amplification observed in human tumors as a step in multistep oncogenesis; deregulated expression of cyclin D1 may reduce the requirement for growth factors and may stimulate in vivo growth.

Neoplastic transformation of normal rat embryo fibroblasts by a mutated p53 and an activated ras oncogene induces parathyroid hormone-related peptide gene expression and causes hypercalcemia in nude mice

Parathyroid hormone-related peptide (PTHRP) is a 141-amino acid protein identified in various carcinomas associated with humoral hypercalcemia of malignancy (HHM). Although the causal role of PTHRP in HHM syndrome has been established, the molecular and cellular mechanism by which PTHRP gene is overexpressed in certain malignancies remains unknown. We have demonstrated in the present study that PTHRP secretion was markedly induced concomitantly with the formation of transformed foci after normal rat embryo fibroblasts (REFs) were co-transfected with an activated ras (ras) and a mutated form of p53 (p53-mt) genes. In either ras- or p53-mt-transfected (nontransformed) cells, only modest or barely detectable secretion of PTHRP was observed, respectively. Northern blot analysis revealed that PTHRP mRNA was markedly induced in fully transformed cells 11 days after transfection with both ras and p53-mt genes. Inhibition of RNA synthesis with actinomycin D resulted in almost complete disappearance of PTHRP mRNA at 2-3 h, suggesting a transcriptional mechanism. Transient transfection experiments revealed that PTHRP promoter activity was induced in ras + p53-mt transfectants. REFs transformed by ras and p53-mt genes and thereby induced to secrete PTHRP in vitro produced aggressively growing tumors associated with HHM syndrome when injected into nude mice. These results suggest that activation of PTHRP gene is closely related to malignant transformation of normal mammalian cells and that ras and p53 may be important regulators of PTHRP gene transcription. The transfection-focus formation system of REFs should provide an excellent model to study the molecular and cellular mechanism underlying concomitant overexpression of PTHRP gene with carcinogenesis.

Overexpression of the PRAD1 oncogene in a patient with prolymphocytic leukemia with t(11;14)(q13;q32)

Prolymphocytic leukemia (PLL) was diagnosed by morphologic and immunophenotypical studies in a 72-year-old Japanese man. Massive splenomegaly was present but lymphadenopathy was minimal in this case. Chromosomal analysis of peripheral mononuclear cells showed t(11;14)(q13;q32) in all metaphases examined, except for one normal karyotype. Northern blot analysis of RNA prepared from leukemic cells obtained from the patient revealed overexpression of the PRAD1/cyclin D1 proto-oncogene, which has not been described previously in patients with PLL.

Bone marrow stromal cells produce and respond to activin A: interactions with basic fibroblast growth factor and platelet-derived growth factor

Activin A, a homodimer of the beta A-chain, regulates hematopoiesis. We recently reported that murine bone marrow (BM) stromal cells, ST2 and MC3T3-G2/PA6, produce activin A [16]. Basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF), potent mitogens of BM stromal cells, induced a rapid increase in beta A-chain mRNA levels and activin secretion in these cells. Cycloheximide (CHX) did not inhibit the increases in beta A-chain mRNA levels, suggesting that these growth factors directly stimulate beta A-chain gene expression. Furthermore, activin A stimulated mitogenesis in ST2 cells, by itself and with bFGF and PDGF. Consistent with this observation, we detected mRNAs of activin A receptors in the murine stromal cells. These findings suggest that BM stromal cells, stimulated by bFGF and PDGF, produce activin A, which may stimulate stromal cells themselves in concert with these peptide growth factors.

Clinical significance of serial measurement of the serum levels of soluble interleukin-2 receptor and soluble CD8 in malignant lymphoma

We serially measured the serum levels of soluble interleukin-2 receptor (sIL-2R) and soluble CD8 (sCD8) in 36 patients with malignant lymphoma (33 non-Hodgkin's lymphoma cases and three Hodgkin's disease cases). The level of serum sIL-2R was significantly elevated in patients with active disease (18) compared to those in remission (18), and correlated with the clinical stage of the lymphoma. The temporal profile of the sIL-2R level reliably represented the disease status, which was judged clinically, during the course of the disease. In three patients, the tumor bulk paralleled the sIL-2R level. On the other hand, a less significant correlation was found between the serum sCD8 level and disease activity. The serial measurement of sCD8 appeared to be less useful for monitoring the disease activity, although there was a significant correlation between the sCD8 and sIL-2R levels. This study indicates that serial measurement of the serum sIL-2R level may be useful for monitoring the tumor burden in response to treatment and for early detection of disease progression in malignant lymphoma.

Overexpression of the PRAD1 oncogene in a patient with multiple myeloma and t(11;14)(q13;q32)

The t(11;14)(q13;q32) chromosomal translocation is associated with several B-cell lymphoproliferative disorders and is thought to result in upregulation of expression of PRAD1/cyclin D1 proto-oncogene. A patient with multiple myeloma of IgG kappa-type with t(11;14)(q13;q32) is now shown to overexpress PRAD1. The clinical stage of the disease was advanced (IIIA), with a myeloma cell count of 94.6% in the bone marrow. Chromosomal analysis of bone marrow cells showed t(11;14)(q13;q32) in five of 20 metaphases as well as other karyotypic features. Northern blot analysis of RNA prepared from myeloma cells revealed overexpression of PRAD1. Multiple myeloma with t(11;14)(q13;q32) has been associated with an aggressive clinical course. Although neither myeloma cells in the peripheral blood nor extramedullary lesions were apparent in the present patient, the myeloma was refractory to several chemotherapeutic regimens from the beginning. Detection of PRAD1 expression may offer an easier alternative to cytogenetic analysis in myeloma and is a potentially useful indicator of a poor prognosis.

Cyclin D1 (Bcl-1, PRAD1) protein expression in low-grade B-cell lymphomas and reactive hyperplasia

Mantle cell (centrocytic) lymphoma (MCL) and occasional cases of B-cell small lymphocytic lymphoma/chronic lymphocytic leukemia (B-SLL/CLL) show a characteristic translocation, t(11:14)(q13;q32) involving rearrangement of the Bcl-1 region. Recently it was shown that the key Bcl-1 region oncogene is cyclin D1/PRAD1; cyclin D1 mRNA was shown to be overexpressed in cases of MCL. We examined cyclin D1 protein expression in low-grade B-cell lymphomas and reactive lymphoid hyperplasias using polyclonal and monoclonal antibodies to cyclin D1 protein. Definite nuclear staining was seen in 15 of 15 MCLs, 1 of 7 B-SLL/CLLs, 0 of 7 reactive hyperplasias, 0 of 10 follicular lymphomas, and 0 of 4 lymphomas of mucosa-associated lymphoid tissue using immunoperoxidase stains on paraffin-embedded sections. Best results were obtained with the affinity-purified polyclonal antibody on microwave-treated, formalin-fixed, paraffin-embedded tissue. MCLs showed diffuse nuclear staining, whereas the one positive B-SLL/CLL showed dot-like or globular nuclear staining. Nuclear cyclin D1 protein can be detected in all cases of MCL and in rare cases of B-SLL/CLL using an immunohistochemical technique on formalin-fixed, paraffin-embedded tissue, and it does not appear to be detectable in reactive hyperplasias and other low-grade B-cell lymphomas. This protein may be useful in subclassification of low-grade B-cell lymphomas.

Erythromycin improves gastrointestinal motility in extremely low birthweight infants

Erythromycin (EM) was administered to five extremely low birthweight infants (ELBWI) with delayed enteral feeding to evaluate the clinical effect on severely impaired gastrointestinal motility. Five patients studied responded well to EM administration without any adverse effects during the course. Four patients were given 15-30 mg/kg per day EM intravenously as a loading and thereafter 3-5 mg/kg per day as a maintenance dose. One patient responded well without loading. The infants could be fed enterally 4, 5, 6, 4 and 2 days after the initiation of EM administration, respectively. Erythromycin administration is a safe and useful way to facilitate gastrointestinal motility in ELBWI who require prolonged ventilator support with an increased risk for nutrient deprivation.

PRAD1/cyclin D1 proto-oncogene: genomic organization, 5' DNA sequence, and sequence of a tumor-specific rearrangement breakpoint

PRAD1 (previously D11S287) is a putative proto-oncogene at 11q13, activated by overexpression through gene rearrangement or gene amplification in several types of human tumors including parathyroid adenomas, centrocytic lymphomas and other B-cell tumors with t(11;14), and breast cancers. PRAD1 (also CCND1) encodes cyclin D1, which may regulate the G1-S phase transition in the cell cycle. Here, we report the cloning and characterization of the chromosomal PRAD1/cyclin D1 gene and the sequence of its promoter region. The gene spans about 15 kb and has 5 exons; its promoter region has Sp1 binding sites and no obvious TATA box, characteristics of housekeeping genes and growth-regulating genes. Furthermore, an E2F binding motif present close to the major transcription start site may be involved in cell cycle-dependent expression of this gene. We also report the sequence of DNAs spanning joining regions of a reciprocal parathyroid hormone/PRAD1 gene rearrangement in a parathyroid adenoma. Comparison with normal sequences suggests that the rearrangement was not a simple break-and-ligate event, but rather involved multiple steps, including two microdeletions and a microinversion. Very short sequences conserved near the breakpoints and symmetrical elements in the eventually inverted DNA segment might have played a role in this illegitimate complex recombination, which may have similarities with a constitutional translocation in Duchenne muscular dystrophy.

Coding sequence of the overexpressed transcript of the putative oncogene PRAD1/cyclin D1 in two primary human tumors

PRAD1 (cyclin D1) is a recently identified member of the family of cyclin genes, believed to play roles in regulating transitions through the cell cycle. The PRAD1 gene, located at 11q13, has been implicated in the pathogenesis of a variety of tumors, including parathyroid adenomas, t(11;14) bearing B-lymphoid tumors (particularly centrocytic lymphomas) where it is highly likely to be the BCL1 oncogene, and possibly in breast carcinomas and squamous cell cancers of the head and neck as well. PRAD1's tumorigenic influence appears to be effected through overexpression of its normal-sized transcript, but it has not been established whether the transcript's coding sequence is normal or contains oncogenic mutations. We have sequenced the coding region of the overexpressed PRAD1 transcript from two primary tumors with clonal PRAD1 region rearrangements: a benign parathyroid adenoma and a malignant centrocytic lymphoma. Each sequence is identical to the normal PRAD1 cDNA sequence, and presumably encodes normal PRAD1 protein. Thus, PRAD1 likely functions as a direct-acting oncogene whose rearrangement in tumors leads to overexpression or deregulated expression of its normal protein product.

Cyclin D and oncogenesis

The D-type cyclins are among the candidate 'G1 cyclins' in higher eukaryotes that may regulate G1-S-phase progression. The human cyclin D1 gene, also known as PRAD1 (and previously as D11S287), is a putative proto-oncogene strongly implicated in several types of human tumors, including parathyroid adenomas, B-cell neoplasms (as the 'BCL-1 oncogene'), and breast and squamous cell cancers. The mechanism by which deregulated production of cyclin D1/PRAD1, and perhaps other D-type cyclins, contributes to tumor development is only beginning to be deciphered.

Cloning and characterization of human cyclin D3, a cDNA closely related in sequence to the PRAD1/cyclin D1 proto-oncogene

Cyclins regulate cell cycle progression by complexing with and activating cdc2 or related kinases. PRAD1/cyclin D1 is a recently discovered putative oncogene in several types of human tumors and may regulate G1-S phase progression. We have cloned a related human cDNA, called cyclin D3, from a placental cDNA library by cross-hybridization with PRAD1. In synchronized HeLa cells, the mRNA levels of PRAD1 and cyclin D3 were regulated reciprocally through the cell cycle: cyclin D3 mRNA levels peaked in S phase, where PRAD1 mRNA was lowest in S. In normal human mammary epithelial (70N) cells synchronized by growth factor deprivation and subsequent growth factor stimulation, PRAD1 expression peaked in G1 and declined before S phase, while cyclin D3 expression rose later in G1 and remained elevated in S. Therefore, the close relationship (53.1% identity) between PRAD1 and cyclin D3 does not necessarily imply redundant functions of these candidate G1 cyclins; they may have distinct roles in progression from G1 through S phase.

Assignment of the human cyclin D3 gene (CCND3) to chromosome 6p----q13

The PRAD1/cyclin D1 gene (CCND1), a member of the D-type cyclin gene family, has been implicated as a protooncogene in parathyroid, lymphoid, and mammary tumors. We cloned and mapped another member of this family, the human cyclin D3 gene (CCND3), to chromosome 6p----q13 using human x rodent hybrids. This assignment raises the hypothesis that cyclin D3 may be involved in the pathogenesis of human neoplasms with abnormalities of chromosome 6.

Erythrocytosis in hypophosphatemic rickets: irreversible complication due to nephrocalcinosis after vitamin D and phosphate therapy

A patient with hypophosphatemic vitamin D-resistant rickets developed secondary erythrocytosis during treatment with large doses of vitamin D2 and phosphate. Erythrocytosis was accompanied by a fall in circulating plasma volume and appeared to have developed as a consequence of nephrocalcinosis because it occurred after the appearance of nephrocalcinosis following several episodes of hypercalcemia and hyperphosphatemia. Nephrocalcinosis and erythrocytosis did not disappear even after recovery of renal function. Thus, the present observations point to the importance of preventing these irreversible complications that could cause renal failure, erythrocytosis, and thrombotic events during the management of hypophosphatemic vitamin D-resistant rickets.

A novel cyclin encoded by a bcl1-linked candidate oncogene

We have previously identified a candidate oncogene (PRAD1 or D11S287E) on chromosome 11q13 which is clonally rearranged with the parathyroid hormone locus in a subset of benign parathyroid tumours. We now report that a cloned human placental PRAD1 complementary DNA encodes a protein of 295 amino acids with sequence similarities to the cyclins. Cyclins can form a complex with and activate p34cdc2 protein kinase, thereby regulating progress through the cell cycle. PRAD 1 messenger RNA levels vary dramatically across the cell cycle in HeLa cells. Addition of the PRAD1 protein to interphase clam embryo lysates containing inactive p34cdc2 kinase and lacking endogenous cyclins allows it to be isolated using beads bearing p13suc1, a yeast protein that binds cdc2 and related kinases with high affinity and coprecipitates kinase-associated proteins. Addition of PRAD1 also induces phosphorylation of histone H1, a preferred substrate of cdc2. These data suggest that PRAD1 encodes a novel cyclin whose overexpression may play an important part in the development of various tumours with abnormalities in 11q13.

Parathyroid hormone-related protein in adult T-cell leukemia-lymphoma

OBJECTIVE

To determine whether parathyroid hormone-related protein is synthesized and secreted by the tumor cells of patients with adult T-cell leukemia-lymphoma.

DESIGN AND PATIENTS

Convenience sample of three patients with adult T-cell leukemia-lymphoma. Two patients developed hypercalcemia, and one patient was normocalcemic.

SETTING

Inpatient facilities at two university-affiliated medical centers.

INTERVENTION

All patients had a lymph node biopsy. In addition, samples of ascitic or pleural fluid, or both, were obtained from these patients.

MEASUREMENTS AND RESULTS

Using RNA blot analysis, we showed that parathyroid hormone-related protein (PTHrP) messenger RNAs (mRNAs) were constitutively expressed in the tumor cells from all patients. Cyclic adenosine monophosphate (cAMP) production-stimulating activity, assessed using osteoblast-like UMR106 cells, was demonstrated in the pleural and ascitic fluids from the two patients who developed hypercalcemia. The elution profiles of the cAMP production-stimulating activity in the ascitic fluid extracts were very similar to those of the tumor extracts from hypercalcemic nude rats that had been implanted with a human cancer tumor.

CONCLUSIONS

Parathyroid hormone-related protein is produced by tumor cells in adult T-cell leukemia-lymphoma, which may be an important factor in the development of hypercalcemia in the patients with this disease. However, the development of hypercalcemia may depend on other factors such as the number of tumor cells, access of the protein into systemic circulation, and the presence of some additional substances.

Hypocalcemia increases and hypercalcemia decreases the steady-state level of parathyroid hormone messenger RNA in the rat

To examine the effects of serum calcium concentrations on PTH biosynthesis, rats were made hyper- (serum total calcium, approximately 3.5 mM) or hypocalcemic (approximately 1.25 mM) and steady-state levels of PTH mRNA in parathyroid cells were measured by the primer extension method using a 32P-labeled synthetic oligomer. PTH mRNA levels increased about twofold in the rats made slightly hypocalcemic by infusion of calcium-free solution and decreased slightly in those made hypercalcemic by CaCl2 infusion (120-150 mumol/h) compared with the levels present in nonfasting control rats. Infusion of calcitonin (0.5 U/h) or EGTA (90 mumol/h) with calcium-free solution increased PTH mRNA levels further (two- to sevenfold) above the levels present in animals infused with calcium-free solution alone. These changes in PTH mRNA levels were observed after 48- but not 24-h infusion, and there was an inverse correlation between PTH mRNA levels and serum calcium concentrations. The results suggest that changes in serum calcium concentrations in the near physiological range regulate the biosynthesis of PTH by affecting steady-state levels of PTH mRNA when hypercalcemia or hypocalcemia continues for a relatively long period.

Expression of parathyroid hormone-related protein in a human T cell lymphotrophic virus type I-infected T cell line

We analyzed human T cell lymphotrophic virus type I (HTLV-I)-infected T cells for the presence of mRNA coding for parathyroid hormone-related protein (PTHrP) by Northern blotting using synthetic DNA probes. We report here that PTHrP mRNAs were detected in a HTLV-I-infected T cell line, MT-2, but not in uninfected T cell or B cell lines, and that PTH-like bioactivity was detected only in the conditioned medium of MT-2 cells. Our study suggests that the pathophysiology of hypercalcemia in patients with adult T cell leukemia/lymphoma may resemble that which occurs with solid tumors.