Allogeneic transplantation following a reduced-intensity conditioning regimen in relapsed/refractory peripheral T-cell lymphomas: long-term remissions and response to donor lymphocyte infusions support the role of a graft-versus-lymphoma effect

Rescue chemotherapy or autologous stem cell transplantation (autoSCT) gives disappointing results in relapsed peripheral T-cell lymphomas (PTCLs). We have retrospectively evaluated the long-term outcome of 52 patients receiving allogeneic SCT for relapsed disease. Histologies were PTCL-not-otherwise specified (n=23), anaplastic large-cell lymphoma (n=11), angioimmunoblastic T-cell lymphomas (n=9) and rare subtypes (n=9). Patients were allografted from related siblings (n=33, 64%) or alternative donors (n=13 (25%) from unrelated and 6 (11%) from haploidentical family donors), following reduced-intensity conditioning (RIC) regimens including thiotepa, fludarabine and cyclophosphamide. Most of the patients had chemosensitive disease (n=39, 75%) and 27 (52%) failed a previous autoSCT. At a median follow-up of 67 months, 27 of 52 patients were found to be alive (52%) and 25 (48%) were dead (n=19 disease progression, n=6 non-relapse mortality (NRM)). The cumulative incidence (CI) of NRM was 12% at 5 years. Extensive chronic graft-versus-host disease increased the risk of NRM (33% versus 8%, P=0.04). The CI of relapse was 49% at 5 years, influenced by disease status at the time of allografting (P=0.0009) and treatment lines (P=0.007). Five-year overall survival and progression-free survival (PFS) were 50% (95% CI, 36 - 63%) and 40% (95% CI, 27 - 53%), respectively. The current PFS was 44% (95% CI, 30-57%). In all, 8 out of 12 patients (66%) who received donor-lymphocytes infusions for disease progression had a response. At multivariable analysis, refractory disease and age over 45 years were independent adverse prognostic factors. RIC allogeneic SCT is an effective salvage treatment with a better outcome for younger patients with chemosensitive disease.

Prevalence of human herpesvirus-6 chromosomal integration (CIHHV-6) in Italian solid organ and allogeneic stem cell transplant patients

The unique phenomenon of human herpesvirus-6 (HHV-6) chromosomal integration (CIHHV-6) may account for clinical drawbacks in transplant setting, being misinterpreted as active infection and leading to unnecessary and potentially harmful treatments. We have investigated the prevalence of CIHHV-6 in 205 consecutive solid organ (SO) and allogeneic stem cell transplant (alloSCT) Italian patients. Fifty-two (38.5%) of 135 solid organ transplant (SOT) and 16 (22.8%) of 70 alloSCT patients resulted positive for plasma HHV-6 DNA by real-time polymerase chain reaction. Seven SOT and three alloSCT patients presented HHV-6-related diseases, requiring antivirals. Two further patients (0.9%) were identified, presenting high HHV-6 loads. The quantification of HHV-6 on hair follicles disclosed the integrated state, allowing the discontinuation of antivirals. Before starting specific treatments, CIHHV-6 should be excluded in transplant patients with HHV-6 viremia by the comparison of HHV-6 loads on different fluids and tissues. Pretransplantation screening of donors and recipients may further prevent the misdiagnosis of CIHHV-6.

Allogeneic stem cell transplantation following reduced-intensity conditioning can induce durable clinical and molecular remissions in relapsed lymphomas: pre-transplant disease status and histotype heavily influence outcome

The safety and efficacy of reduced-intensity conditioning (RIC) followed by allogeneic stem cell transplantation (SCT) for relapsed lymphomas remains unresolved. We conducted a prospective, multicentered, phase II trial. A total of 170 relapsed/refractory lymphomas received a RIC regimen followed by SCT from sibling donors. The primary study end point was non-relapse mortality (NRM). Histologies were non-Hodgkin's lymphomas (NHL) (indolent (LG-NHL), n=63; aggressive (HG-NHL), n=61; mantle cell lymphoma (MCL), n=14) and Hodgkin's disease (HD, n=32). Median follow-up was 33 months (range, 12-82). The results show that frequencies were as follows: cumulative NRM at 3 years, 14%; acute and chronic graft-versus-host disease (GVHD) 35 and 52%, respectively; 3-year overall survival (OS), 69% for LG-NHL, 69% for HG-NHL, 45% for MCL and 32% for HD (P=0.058); and 3-year relapse incidence, 29, 31, 35 and 81%, respectively (P<0.001). Relapse risk differed significantly at 3 years between follicular lymphoma (FL) and chronic lymphocytic leukemia (CLL) (14 versus 46%, P=0.04). Molecular remission occurred in 94 and 40% (P=0.002) of patients with FL and CLL, respectively. On multivariate analysis, OS was influenced by chemorefractory disease (hazard ratio (HR)=3.6), diagnosis of HD (HR=3.5), and acute GVHD (HR=5.9). RIC allogeneic SCT is a feasible and effective salvage strategy in both indolent and aggressive NHL.

Treatment of refractory chronic GVHD with rituximab: a GITMO study

The anti-CD20 chimaeric monoclonal antibody Rituximab has recently been shown to induce significant clinical response in a proportion of patients with refractory chronic graft-versus-host disease (cGVHD). We now report 38 patients, median age 48 years (22-61), receiving Rituximab for refractory cGVHD, assessed for clinical response and survival. Median duration of cGVHD before Rituximab was 23 months (range 2-116), the median number of failed treatment lines was 3 (range 1 to > or =6) and the median follow-up after Rituximab was 11 months (1-88). Overall response rate was 65%: skin 17/20 (63%), mouth 10/21 (48%), eyes 6/14 (43%), liver 3/12 (25%), lung 3/8 (37.5%), joints 4/5, gut 3/4, thrombocytopaenia 2/3, vagina 0/2, pure red cell aplasia 0/1 and, myasthenia gravis 1/1. During the study period 8/38 died: causes of death were cGVHD progression (n=3), disease relapse (n=1), infection (n=3), sudden death (n=1). The actuarial 2 year survival is currently 76%. We confirm that Rituximab is effective in over 50% of patients with refractory cGVHD and may have a beneficial impact on survival.

Bone marrow failure associated with human herpesvirus 8 infection after transplantation

BACKGROUND

Human herpesvirus 8 (HHV-8) infection has been linked to the development of Kaposi's sarcoma and to rare lymphoproliferative disorders.

METHODS

We used molecular methods, serologic methods, in situ hybridization, and immunohistochemical analyses to study HHV-8 infection in association with nonmalignant illnesses in three patients after transplantation.

RESULTS

Primary HHV-8 infections developed in two patients four months after each received a kidney from the same HHV-8-seropositive cadaveric donor. Seroconversion and viremia occurred coincidentally with disseminated Kaposi's sarcoma in one patient and with an acute syndrome of fever, splenomegaly, cytopenia, and marrow failure with plasmacytosis in the other patient. HHV-8 latent nuclear antigen was present in immature progenitor cells from the aplastic marrow of the latter patient. Identification of the highly variable K1 gene sequence of the HHV-8 genome in both the donor's peripheral-blood cells and the recipients' serum confirmed that transmission had occurred. HHV-8 viremia also occurred after autologous peripheral-blood stem-cell transplantation in an HHV-8-seropositive patient with non-Hodgkin's lymphoma. Reactivation of the infection was associated with the development of fever and marrow aplasia with plasmacytosis; there was no evidence of other infections. HHV-8 transcripts and latent nuclear antigen were expressed in the aplastic marrow but not in two normal marrow samples obtained before transplantation.

CONCLUSIONS

Primary HHV-8 infection and reactivation of infection may be associated with nonneoplastic complications in immunosuppressed patients.

Nonmalignant disease associated with human herpesvirus 8 reactivation in patients who have undergone autologous peripheral blood stem cell transplantation

Fever, cutaneous rash, and hepatitis-for which an infectious cause was suspected-developed in an Italian patient with non-Hodgkin lymphoma after autologous peripheral blood stem cell (PBSC) transplantation. Polymerase chain reaction (PCR) with degenerate primers for the highly conserved DNA polymerase gene of herpesviruses detected herpesvirus sequences 100% identical to human herpesvirus-8 (HHV-8) in serial cell-free serum samples, collected immediately before or concomitant with the occurrence of clinical symptoms; no other common infections were documented. The presence of the HHV-8 genome (clade C) was confirmed by PCR with HHV-8-specific primers for orf 26 and orf-K1. HHV-8 viremia was undetectable either before transplantation or when the patient was clinically asymptomatic. Semiquantitative PCR analysis showed variations of the viral load correlating with the clinical status. Anti-HHV-8 antibodies were detected before and after transplantation by an immunofluorescence assay for lytic antigens. Active HHV-8 infection may be associated with nonmalignant illness after PBSC/bone marrow transplantation.

Retrospective analysis of mantle cell lymphoma: experience of the "Gruppo Italiano per lo Studio dei Linfomi" (GISL)

BACKGROUND AND OBJECTIVE

Mantle cell lymphoma is a recently recognized histologic entity with specific biological and clinical features. Clinically, the reported unfavorable outcome of these patients has focused attention on this category of non-Hodgkin's lymphoma (NHL).

DESIGN AND METHODS

The slide specimens of 69 NHL patients, originally classified as Working Formulation (WF) group B and E, were reviewed. The clinical features at presentation, response to therapy, response duration and survival were analyzed in cases reclassified as MCL. The correlation between clinical and histologic characteristics and the final outcome was evaluated.

RESULTS

Out of 69 cases, 34 specimens were reclassified as MCL; in 6 patients, previously classified as WF group B, the nodular pattern was confirmed; in 2 instances the blastoid form was recognized. After a median follow-up of 35.7 months, the entire series displayed a median overall survival of 41.2 months; a significantly longer survival was associated with the nodular histologic pattern, IPI score < 2, response achievement, and a higher Hb level. The vast majority of patients received anthracycline-containing combination chemotherapy. Complete remission rate was 38.8% and overall response rate was 67.6%; response achievement was significantly influenced only by Hb level. Median response duration was 23.3 months.

INTERPRETATION AND CONCLUSIONS

The present study confirms the unfavorable clinical course of MCL and the possible need for an alternative therapeutic strategy for this NHL category. Therefore, the correct identification of MCL at diagnosis appears of relevance.

Occurrence of a novel t(11;19)(q13;q13.3) in complete remission of acute promyelocytic leukemia

A woman with t(15;17) and PML/RAR alpha positive acute promyelocytic leukemia (APL-M3v) achieved a complete remission (CR) with cytogenetic and molecular conversion, after one-month ATRA plus idarubicin treatment. During CR, less than one-month after consolidation therapy with topoisomerase II inhibitors, a novel t(11;19) (q13;q13.3) was detected in peripheral blood stem cells and later in harvest bone marrow cells. Persisting CR and the negativity for BCL1 and PRAD1 genes rearrangement, the autotransplantation was performed, with good outcome. The patient is still in CR eighteen months post-transplant, in spite of the persistence of a small t(11;19) clone in BM cells. The emergence of a novel chromosomal change during CR of acute leukemia is a rare phenomenon. This is the first t(11;19)(q13;q13.3) described in APL. This finding raises the issue of whether the abnormal karyotypes at remission might represent a risk of tumor recurrence. The meaning of this genomic instability is yet unknown.

[The treatment of the cardiac patient in dentistry and oromaxillofacial surgery. I. The practical management of patients with arrhythmias]

Cardiac patients consist of a high incidence rate in odontostomatology, both clinical and surgical. Moreover this serious complication disease conditions odontostomatological and, particularly, surgical works. In this article the authors present the results of several years of research carried out to obtain a correct clinical and therapeutic approach for clinical and surgical dentistry. After an introduction on the clinical features of heart diseases the most important clinical cases of heart dysrhythmia are discussed: like, i.e. hypokinetic arrhythmia, hyperkinetic arrhythmia and the management of patients with pacemakers. The principal diacritic features of dysrhythmic diseases are illustrated. Anxiety is a sort of disease not directly related with dysrhythmia. Moreover a lot of clinical studies find in heart arrhythmia the principal problem caused by anxiety on heart physiology. Consequently the authors describe anxiety in the same part of pathologies commonly known as heart dysrhythmia. In the last phase the authors illustrate the most opportune therapeutic steps corresponding to the principal pathologies described above. These matters were dealt with from an odontostomatological point of view. The results obtained suggest the necessity of keeping to the management that was described. Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.

[The treatment of the cardiac patient in dentistry and oromaxillofacial surgery. II. The practical management of patients with hemodynamic pathologies]

When odontostomatological or surgical treatment is performed we suggest, in a first phase, to distinguish cardiac patients from the others. In a second phase a careful nosological diagnosis will be performed. Consequently, patients' medical history plays a fundamental role in both diagnostic phases. In this article the authors present the results of several years of research carried out to obtain a correct clinical and therapeutic approach for clinical and surgical Odontostomatology. After an introduction on the clinical features of heart hemodynamic pathologies the most important clinical cases are discussed: like, for example, acardiohemia, valvulopathies and heart decompensation. The principal diacritic features of hemodynamic diseases are illustrated. Essential hypertension (borderline and resident) is a sort of disease not directly related to hemodynamics pathology. Moreover a lot of clinical studies find in heart hemodynamic pathologies the principal problem caused by hypertension on heart physiology. Consequently the authors describe essential hypertension in the same part of pathologies commonly known as heart hemodynamic pathologies. In the last phase the authors illustrate the most opportune therapeutic steps corresponding to the principal pathologies above-described. These matters were dealt with from an odontostomatological point of view. The results obtained suggest the necessity of keeping to the management that was described. Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.

[Treatment of the patient with a coagulation defect in oral and maxillofacial surgery. III. The management of patients in a hypocoagulative state because of a hemophilic-type primary pathology]

Hemophilia plays a particularly important role among the diseases caused by abnormal coagulation. Defective blood-clotting factor diseases have a particular importance between coagulopathies: hemophilia, among these hematic disorders, plays a principal role. In this paper the authors present the results of scientific research on hemophilic disease carried out to obtain a correct clinical and therapeutic approach for clinical and surgical Odontostomatology. The authors, after having presented in short the physiopathologic function of coagulation factors, illustrate the clinical and therapeutic aspects of Hemophilia A and Hemophilia B. The correct Odontostomatological and Maxillo-Facial Surgical approach is presented as the result of the authors' research. Also von Willebrand's disease is illustrated even if it is not exactly a hemophilic disease. This is because all hemophilias must produce a gynephoric inheritance pattern. Nevertheless clinical, therapeutic and molecular biology appearance suggests the illustration of von Willebrand's disease together with hemophilias. Von Willebrand's disease can be divided into three nosologic groups and to each one corresponds a particular clinical and therapeutic management. Such cases are illustrated and examined from an Odontostomatologic point of view. The results obtained suggest the necessity of keeping to the management that was described. Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.

[Management of facial pain resulting from cancer in oral and maxillofacial surgery]

Pain, which is among the most prevalent symptoms experienced by cancer patients, must absolutely be treated. The most important biologic effects of this sort of pain plays on patients' psychosociality. This is in reference to the quality of pain, the amount of pain and to the character of the patients. Actually, pain only in appearance is presented as a symptom; it is usually a disease. Patient assessment, the use of anticancer therapies and systematically administered non-opioid and opioid analgesics are pivotal. Practical aspects of cancer pain treatment include both drug selection, method of analgesic administration: selection of the appropriate route, dose titration and an understanding of the management of side effects. Pain therapy includes another series of possibilities like the use of adjuvant analgesics, psychological therapies, physiatric techniques and invasive interventions such as the use of intraspinal drugs, neural blockade and neuroablative techniques. This kind of therapy must be employed at all times, whether the case may be resolved surgically or not. So we think that pain can be effectively treated. This study was carried out to obtain the correct therapeutic approach for facial cancer pain syndrome. The research was performed on seven women and thirteen men with a mean age of 58 years. All the patients' clinical appearances were standardized with care. Study participants included odontostomatologists and anesthesiologists with experience of controlling cancer pain. The sensation of pain was quantified by means of the Visual Analogue Scale (VAS) while their psychosocial ability was assessed with the Karnofsky Performance Scale (KPS). In this way the authors hoped to obtain a good quality of standardization. The study was performed for a period of two months. The conclusions are that Trans Epidermis Nervous Stimulation (TENS) offers positive results for variable periods and only in 60% of patients with a low level of pain. The use of antiphlogistic non-steroid drugs and of opioid drugs, with a particular management requested from the personal clinical status of each patient, result as being the most effective therapeutic resource. Such therapies must be employed, whether the case may be resolved surgically or not. Nevertheless it is necessary to realize that drugs or other therapies for cancer pain are independent and propaedeutic to each surgical approach. Finally, the use of opioids is addressed in the management of patients with pain that is refractory to other interventions. This approach can provide adequate relief to the vast majority of patients. We find the morphinomania risk in cancer pain patients is not scientifically wellfounded.

[Management of patients with coagulation disorder in oral and maxillofacial surgery. I. Management of patients with hypocoagulation caused by primary thrombocytopathy]

Any oral and maxillo-facial surgical treatment, however urgent it may be, must not include pathological states in which the patient's life may be particularly at risk as, for example, with Disseminated Intravascular Coagulation (DIC) or throm-botic thrombocytopenic purpura. In this article the authors present the result of studies carried out on the nosology of thrombocytopathy from an odontostomatological point of view. Thrombocytopathy can be divided into two groups: the first including the pathologies with a predominant defective number of thrombocytes (i.e.: thrombocytopenia, thrombocythemia, thrombocyto-sis), the second including forms with predominant qualitative defects (commonly known as thrombocytopathies). The authors, after having presented in short the physiopathologic functions of thrombocytes, illustrate the clinical and therapeutic aspects of the most important thrombocytopathies. Morbus Maculosus Werhofii, Glanzmann's disease, Bernard-Soulier syndrome, thrombocytopathies from defective reaction of release, Thrombocytopathies from defective procoagulant activity of blood plaques, thrombocytopathies in linkage to other genetic anomalies, von Willebrand's pseudodisease and a lot of acquired thrombocytopathies are identified. In the last part the authors illustrate the most opportune clinical steps corresponding to the most important thrombocytopathies. The results obtained suggest the necessity of keeping to the management that was described, Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.

[Management of patients with coagulation defect in oral and maxillofacial surgery. I. Management of patients with drug-induced hypocoagulation]

Odontoiatric problems, clinical and surgical, connected with defective coagulation, are very frequent. Such cases can be divided into two groups: in the first we find patients with iatrogenic coagulopathy while in the second we find patients with hypocoagulative diseases. In this article the authors present the result of several years of research carried out to obtain a correct clinical and therapeutic approach for clinical and surgical Odontostomatology. After an introduction on clinical pharmacology and the use of anticoagulants, the principal clinical cases are discussed. Various laboratory tests evaluating patients with pharmacological coagulopathy are examined. The most specific and significant tests are illustrated following up the authors experiences. In the last part the authors illustrate cases corresponding to the two serious and frequent complications that can be found in patients with iatrogenic coagulopathy: hematorrhea and thromboembolism. These matters were dealt with from an Odontostomatologic point of view. The results obtained suggest the necessity of keeping to the management that was described. Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.

Hepatitis C virus infection in subsets of neoplastic lymphoproliferations not associated with cryoglobulinemia

Hepatitis C virus (HCV) is both hepatotropic and lymphotropic and a clear-cut association has been proposed between HCV infection and mixed cryoglobulinemia (MC), a benign lymphoproliferative disorder, which sometimes evolves into a frank malignant B cell non-Hodgkin's lymphoma (B-NHL). Moreover, in the presence of antibodies to HCV, as well as of HCV-specific genomes has been reported in the sera of over 37% patients with B-NHL, not associated with MC. Thus, we decided to perform both a serologic and a molecular study to give insights into a possible relationship between HCV infection and neoplastic lymphoproliferations. We used ELISA and RIBA tests to show that anti-HCV antibodies were present in the serum of 29 out of 69 unselected B-NHL patients (42%), while seropositivity in a healthy population was about 1%. The prevalence of anti-HCV antibodies was low in definite subsets of B lymphoid disorders, including multiple myeloma, Waldenström's macroglobulinemia and monoclonal gammopathies of undetermined significance. Then, using reverse transcriptase polymerase chain reaction, we detected HCV sequences directly in the pathologic lymph node biopsies in 13 out of 34 B-NHL cases, and in particular in six out of eight low-grade lymphomas of MALT type and in five out of eight centroblastic-centrocytic follicular lymphomas. In contrast, the peripheral blood samples from 10 B cell chronic lymphocytic leukemia patients resulted negative for the presence of HCV genomes. Similarly, viral sequences were absent in 10 T cell NHL, while only one out of the 14 Hodgkin's disease cases tested resulted positive. Finally, we used a PCR-based assay to characterize the genotypes (I-IV) present in the positive lymphomatous tissues. The presence of both serologic and molecular markers of HCV infection in a high percentage of certain types of B-NHL, not associated with cryoglobulinemia, and its absence from other lymphoproliferative diseases extends the spectrum of HCV-associated lymphoproliferations arguing in favor of some role of this viral infection in the pathogenesis of the malignant proliferation of definite B lymphoid populations.

MOPP/EBV/CAD hybrid chemotherapy with or without limited radiotherapy in advanced or unfavorably presenting Hodgkin's disease: a report from the Italian Lymphoma Study Group

PURPOSE

We explored the feasibility, toxicity, and preliminary results of a chemotherapy (CT) regimen, mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/epidoxirubicin, bleomycin, and vinblastine (EBV)/lomustine (CCNU), doxorubicin, and vindesine (CAD), derived through hybridization, shortening, and intensification of a corresponding 10-drug alternating combination CAD/MOPP/doxorubicin, bleomycin, and vinblastine (ABV), effective in treatment of advanced Hodgkin's disease (HD).

PATIENTS AND METHODS

Hybridization involved all drugs except CCNU and mechlorethamine, which were administered in alternating cycles; the length of therapy was reduced from nine to six cycles. The average projected drug doses during the six cycles were increased by 42%, with an overall 1.54 dose-intensification; epidoxorubicin was substituted for doxorubicin at equivalent tumoricidal doses. Radiotherapy (RT) was optional and its indications were limited.

RESULTS

Eighty assessable patients with previously untreated, advanced or unfavorably presenting HD were treated in nine cooperating institutions between 1988 and 1991. RT was delivered to 22 patients. Remissions were complete (CR) in 75 patients (93%), partial in three (4%), and null in two (3%). The median relative dose-intensity was 0.71 for the overall regimen. Three of five patients who failed to achieve CR, and two of the four who relapsed, received lower relative dose-intensive cycles. Nonhematologic toxicity was acceptable, but there was considerable hematologic toxicity. Fatal gastrointestinal bleeding was seen in one patient.

CONCLUSION

Caution is advised due to the short median follow-up period. Nevertheless, in addition to the excellent response rate, (1) the results were reached through abbreviation, intensification, and hybridization of an existing alternating regimen; (2) RT had limited use in this program, which may have contributed to lowering the risk of second tumors; and (3) the results were obtained in a multicenter study (a condition that often impairs results from clinical trials).

bcl-2 gene expression in hematopoietic cell differentiation

Nonrandom translocations with breakpoint at band q21 on chromosome 18 might cause bcl-2 gene deregulation and might contribute to neoplastic transformation in human lymphomas. As the pattern of expression of bcl-2 in hematopoietic cells is still unclear, we have measured the level of the corresponding messenger RNA (mRNA) in a variety of myeloid and lymphoid cell malignancies not usually associated with the t(14;18) translocation. Molecular genetic analysis showed that bcl-2 was rearranged in only 2 of 77 patients: one was affected by hairy cell leukemia and one by diffuse small cleaved cell lymphoma with peripheral blood invasion. Although in rare cases of myeloid leukemia fairly high levels can be found, the expression of bcl-2 appears to be typical of certain lymphoid malignancies. High levels of bcl-2 mRNA had been found, previously, in established pre-B-cell lines. However, in fresh specimens, the peak level of bcl-2 expression shifts to a more differentiated cell type, represented by the long-living B lymphocytes that are found in most cases of chronic lymphocytic leukemia. bcl-2 gene product might have a role in prolonging cell survival and, even in the absence of translocations, might contribute to some of the biologic features that are typical of this disorder.

Human herpesvirus-6 in human lymphomas: identification of specific sequences in Hodgkin's lymphomas by polymerase chain reaction

In search of a possible involvement of the human herpesvirus type 6 (HHV-6) in human Hodgkin's and non-Hodgkin's lymphomas, we studied the levels of anti-HHV-6 antibodies in the sera of 94 cases by an immunofluorescence assay, as well as the presence of HHV-6 sequences in the affected tissues of 66 cases by polymerase chain reaction, using one set of primer oligonucleotides. Our results showed higher anti-HHV-6 antibody titers in human lymphomas than in normal blood donors, but the difference is statistically significant only when normal donors are compared with Hodgkin's lymphoma cases. HHV-6 sequences were detected in 3 of 25 Hodgkin's lymphomas and 0 of the 41 cases of non-Hodgkin's lymphomas studied. The three cases positive for HHV-6 sequences belong to the nodular sclerosis-lymphocyte depletion histologic subtype and share remarkable similarities in their clinical features. Furthermore, Southern blot analysis of total genomic DNA obtained from the neoplastic tissues of two of the three patients showed the same restriction fragment length polymorphism. Our results suggest that: (1) the high level of anti-HHV-6 antibodies in Hodgkin's disease is due to an activation of the immune system not related to the presence of HHV-6 sequences in affected lymph nodes; (2) the presence of HHV-6 sequences in human lymphoid tissues is not a frequent event, rather it is in fact a very rare event in non-Hodgkin's lymphomas, while in Hodgkin's cases it is more frequent than previously reported on the basis of Southern blot analysis; and (3) the presence of HHV-6 sequences in Hodgkin's lymphomas may have a relation with the clinical presentation of the disease.

Kappa light chain gene rearrangement in a T-cell lymphoma

Forty-three patients were studied to determine whether light chain gene rearrangements may occur in hematopoietic cells not pertaining to the B-lineage. In only one patient, affected by T-cell lymphoblastic lymphoma, one kappa light chain allele was rearranged. Neither at the protein level nor at the RNA level the rearranged gene was expressed. These data confirm that, although rarely, kappa light chain gene rearrangements may occur in neoplastic T-cells. Furthermore, as in our patient Ig heavy chain genes retained a germline configuration, the present data demonstrate that kappa light chain gene rearrangements may occur regardless of Ig heavy chain gene arrangement.

T-cell receptor genes expression in B-cell leukaemias

Using Northern-blot analysis we have studied the expression of T-cell receptor (TCR) alpha, beta and gamma chain genes in primary cells obtained from 36 leukaemic patients. Fifteen patients had myeloid leukaemias, two had T-cell leukaemias, and 19 leukaemias corresponding to various stages of B-lymphocyte differentiation. We observed that truncated TCR beta mRNAs were produced in B-cells at relatively high levels even in the absence of detectable gene rearrangements. Ti alpha mRNAs of abnormal size were also frequently found. Such transcripts were not detectable in total RNA extracted from leukaemic myeloid cells. Factors allowing Ti alpha and beta gene transcription must be active in leukaemic pre-B and B cells but not in myeloid cells. Neither B-lineage nor myeloid leukaemias expressed TCR gamma gene at detectable levels.

Myeloperoxidase gene expression in blast cells with a lymphoid phenotype in cases of acute lymphoblastic leukemia

By using a cDNA clone of the myeloperoxidase (MPO) gene, we have studied, by Northern blot analysis, the level of MPO mRNA in eight cases of acute lymphoblastic leukemia (ALL). The blast cell populations studied were characterized by morphologic, cytochemical, immunochemical, and molecular criteria. With all the methods used the populations were found to be highly homogeneous and showed a typical lymphoid phenotype. In particular, the Ig heavy-chain gene rearrangement was largely prevalent, and the germ line configuration was almost absent. However, in three of eight cases, high levels of MPO mRNA were detected. The remarkable homogeneity of the cell populations examined suggests that the MPO mRNA observed was present in cellular elements certainly identified as lymphoid. The absence of contamination by myeloid cells was confirmed by the results of Western blot analysis of the proteins of the cell population studied: no MPO protein was detectable. The levels of mRNA observed were high enough to be comparable to those observed in a promyelocytic cell population.

Prognostic significance of "short-term" effects of chemotherapy on MYC and histone H3 mRNA levels in acute leukemia patients

We have found that administration of chemotherapy alters expression of growth-regulated genes in leukemia blast cells. To determine if such changes might be correlated with therapeutic outcome, we studied steady-state mRNA levels of MYC and histone H3 in the leukemic blasts of patients just prior to and 24 hr after the administration of the first doses of antileukemic drug therapy. Among nine patients with acute myelogenous leukemia, mRNA levels of MYC and histone H3 were reduced in five patients, and hematologic remission was achieved in three of these individuals. No remission was obtained in the four patients without reduction in MYC and histone H3 mRNA. Among acute lymphocytic leukemia patients, the mRNA levels of MYC and/or histone H3 were reduced by the therapy in seven of nine patients. A complete hematologic remission was obtained in five of them, and a partial remission was obtained in the other two. No remission was obtained in the patients in which MYC and H3 mRNA levels were unaffected by the therapy. These studies are of interest because they suggest that a decrease in the mRNA levels of MYC and histone H3 24 hr after a single dose of antineoplastic drugs may predict which patients will achieve complete remission; lack of reduction in these mRNAs correlates with failure to achieve remission. In addition, these studies also provide further proof of the heterogeneity of altered growth regulation among human leukemias.

Alteration and abnormal expression of the c-myc oncogene in human multiple myeloma

Structural alterations of the c-myc oncogene in human Burkitt's lymphoma and mouse plasmacytoma suggest that this oncogene is involved in several B cell neoplasms. The possibility of c-myc alterations in human myeloma has not been explored, probably because the low proliferative activity characteristic of this tumor impairs the propagation of representative cell lines for the performance of adequate cytogenetic studies. This report describes alterations in the c-myc locus with concomitant elevated expression of mRNA in the tumor cells of two of 37 patients with multiple myeloma. In one case, somatic cell hybrid studies revealed that the cloned rearranged DNA was entirely derived from chromosome 8, thus indicating a novel mechanism of c-myc activation different from that in Burkitt's lymphoma. Seven other patients exhibited five- to 12-fold overexpression of c-myc RNA when compared with normal marrow cells. Elevated mRNA expression in about one fourth of our patients suggests that the c-myc oncogene has a pathogenetic role in the evolution of multiple myeloma.

HLA class II antigen associated invariant chain gene expression in malignant lymphoma

Expression of the gene encoding HLA class II antigen-associated invariant chain was studied in several types of fresh human malignant lymphoma by Northern blot analysis or slot-blot analysis. The invariant chain mRNA levels decreased with the stage of B-lymphocyte differentiation to plasma cells such as in immunoblastic lymphoma (IBL) or multiple myeloma (MM). The invariant chain gene (In-gene) was expressed in diffuse large cell lymphoma (DLCL), while its expression was hardly detected in IBL. It is suggested that the difference in In-gene expression between DLCL and IBL could be useful in distinguishing these two morphologically similar diseases.

Philadelphia-positive chronic myeloid leukemia with a chromosome 22 breakpoint outside the breakpoint cluster region

In chronic myelogenous leukemia (CML) the reciprocal translocation resulting in the Philadelphia chromosome (Ph1) leads to the formation of a chimeric transcriptional unit carrying both c-abl and bcr genetic information whose transcript is a new fused mRNA of 8.5-kilobases (kb) and whose translational product is a 210-kD phosphoprotein with tyrosine kinase activity implicated in the pathogenesis of CML. Twenty patients affected by Ph1-positive CML were studied by Southern blot analysis with bcr. Unexpectedly, in three Ph1-positive patients, the breakpoint of chromosome 22 was located neither inside the bcr region nor 5' to it. Northern blot analysis of the RNAs of two of these patients showed the absence of a detectable 8.5-kb chimeric mRNA. In the third patient a chimeric mRNA was detected by a c-abl cDNA probe but failed to hybridize with a bcr cDNA probe and showed very low hybridization levels with further 5' bcr cDNA probes. The possibility is raised that in CML a breakpoint outside bcr might either still allow the formation of a chimeric mRNA, possibly through alternative splicing mechanisms, or might prevent the transcription of the chimera. In the latter case different molecular events resulting in the formation of a Ph1 chromosome may underlie the same myeloid neoplastic phenotype.

Establishment and characterization of a human IgA-kappa-secreting plasma cell line (MT3)

We have established a new human plasma cell line from the peripheral blood of a patient with an IgA-kappa plasma-cell leukemia. Morphological, immunological, cytogenetic and molecular studies confirm that the cultured cells are derived from the same clone of leukemic plasma cell in vivo. The established cell line (MT3) grows in suspension, secretes high amounts of IgA kappa and exhibits morphological and ultrastructural characteristics of plasma cells. Surface marker analysis shows that both primary and cultured cells express the plasma-cell-associated antigens PCA-1 and T10, while specific B- and T-cell determinants and EBV nuclear antigen are undetectable. In the established cell line a few cells express Ia-like and CALLA antigens. Cytogenetic analysis of MT3 cells reveals a prevalent hypertriploid karyotype with constant chromosomal aberrations consisting of 14q+, 22q- and marker chromosomes.

The effect of cytosine-arabinoside treatment on the overexpression of c-myc protooncogene in a case of prolymphocytic leukemia

An unusually high level of expression of the c-myc protooncogene was observed in peripheral blood lymphocytes of a patient with prolymphocytic leukemia (atypical chronic lymphocytic leukemia). The overexpression of c-myc could not be attributed to a high level of proliferating activity of the leukemic cells in the blood. Treatment with cytosine-arabinoside at high doses abolished this altered expression of c-myc and resulted in a twofold increase in the expression of a gene sequence encoding the invariant gamma-chain of class II histocompatibility antigens, preferentially expressed in resting B lymphocytes. These observations suggest that the leukemic cells may have been arrested in the cell cycle outside the G0 phase. Our findings demonstrate that growth-regulated genes can be useful molecular markers of diseases with altered mechanisms of cellular proliferation.

HLA-associated invariant chain gene expression in human B cell neoplasia

The expression of the gene encoding the HLA-DR associated invariant chain (In-gene) in human B lymphocytes was analyzed by determining the level of invariant chain, mRNA in peripheral blood and bone marrow cells of several patients affected by hematological malignancies. In B cell neoplasms representative of different stages of B lymphocyte differentiation, In-gene activation was an early event that may occur in pre-B cells before immunoglobulin gene transcripts are detectable. The highest level of invariant chain mRNA were observed at an intermediate maturation stage corresponding to sIg, Ia, and B1 positive peripheral blood lymphocytes. At the terminal stage of B lymphocyte differentiation, the In-gene was turned off. In leukemic cell populations, the pattern of temporal activation of the In-gene corresponded to the pattern of activation of the genes encoding the HLA-DR alpha and beta chain.

Expression of growth-regulated genes in human acute leukemias

We have investigated the expression of six growth-regulated genes (c-myc, c-myb, p53, 4F1, 2F1, and ornithine decarboxylase) and the S-phase-specific histone H3 gene in acute myeloid and lymphoid leukemic cells. We have purposely chosen three growth-regulated protooncogenes that share similar biological features and three gene sequences that have in common the cell cycle dependence of their expression in cells of different tissue and in different species. The level of expression was determined by measuring the amounts of specific RNA by Northern blot analysis. Levels of expression of the six growth-regulated genes were compared to the level of expression of the S-phase-specific H3 gene and among themselves. This method distinguishes the increased expression of a growth-regulated gene due to a true altered activation from over-expression which simply reflects an increase in the fraction of cycling cells. We have found that six of 14 patients with acute leukemias have markedly high ratios of c-myc/H3, c-myc/p53, and c-myc/c-myb expression. Two patients with altered c-myc expression have also a high ratio p53/H3. Within the group of cell cycle-dependent genes the ratios of expression seem in the overall much more regular with the clear exception of a patient with acute myelogenous leukemia in which the ratios 4F1/H3 and 2F1/H3 are significantly increased. A possible interpretation of these findings is that the fraction of noncycling leukemic cells that often constitute the majority of the entire leukemic population is in some cases in a true resting state, whereas in other cases heterogeneous degrees of growth arrest might occur. The altered expression of c-myc seems the feature most commonly associated with this putative growth arrest of leukemic cells suggesting that this gene may contribute to the impairment of proliferative control that is associated with the leukemic phenotype.

HLA-DR-associated invariant chain is highly expressed in chronic lymphocytic leukemia

Total RNA extracted from peripheral blood lymphocytes of a patient with B-cell chronic lymphocytic leukemia (CLL) and the poly (A+) RNA was purified. A cDNA library was constructed and approximately 4,000 clones were screened in order to identify genes preferentially expressed in CLL. A relatively low repetition frequency characterizes the majority of the abundant mRNA species present in CLL lymphocytes. One clone, corresponding to the mRNA encoding the HLA-DR-associated invariant chain, was selected and its expression was examined in different leukemic cell populations and in normal tissues. DNA-RNA hybridization studies showed that the invariant chain mRNA (In-mRNA) is detectable in RNA preparations from human blood cells and their precursors, whereas no In-mRNA is found in several other tissues examined. Among various normal and leukemic leukocyte populations, the highest levels of In-mRNA are found in CLL. Therefore, a role of In-chain mRNA as a marker of CLL is proposed. Our data support a relationship between high levels of invariant chain mRNA and the out of cycle condition of CLL peripheral blood lymphocytes.

Altered expression of G1-specific genes in human malignant myeloid cells

We have studied the expression of cell-cycle genes specific to the G1 (2A9, 2F1, 4F1, c-myc) and S (histone H3) phases of the cell cycle in normal and malignant human myeloid cycling cells. The levels of expression were determined by measuring the amounts of specific RNA in blot hybridization assays. Levels of expression of the G1 genes were compared to the level of expression of the S-phase-specific H3 gene. This method can distinguish whether an increased expression of G1 genes is truly due to deregulation or simply reflects an increase in the fraction of proliferating cells. In a normal asynchronous system provided by the bone marrow cells of three normal donors, the expressions of the four G1-specific genes 2A9, 2F1, 4F1, and c-myc, and of the S-phase-specific gene H3 were in ratios that differed little from one individual to another. In the total RNA of eight patients in the chronic phase of chronic myelogenous leukemia, a high level of expression of G1 cell-cycle genes was paralleled by a high level of expression of the S-phase H3 gene, simply reflecting an increase in the fraction of proliferating cells. In patients with acute myelogenous leukemia (AML), the RNA levels of 2F1 and 4F1 paralleled the expression of H3-i.e., the ratios of expression 2F1/H3 and 4F1/H3 were the same as in normal bone marrow cells. However, in 9 of 10 patients with AML we found that the expression of c-myc was elevated with respect to H3 expression. The expression of 2A9 (with respect to H3) was also elevated in some of these AML patients. Two important conclusions can be drawn from these findings: increased levels of a G1-specific RNA in a tumor may not indicate overexpression of that gene but may instead simply reflect the fraction of proliferating cells; and in some patients with AML, however, the expression of certain G1 genes is truly deregulated and might contribute to the impairment of proliferative control that is associated with this phenotype.

Structure of the human gene encoding the invariant gamma-chain of class II histocompatibility antigens

The primary structures of a cDNA and the genomic DNA of a gene selectively expressed in chronic lymphocytic leukemia were determined. A computer search of the nucleotide sequence data bank identified this gene as the invariant gamma-chain associated with class II histocompatibility antigens. The invariant gamma-chain genomic sequence spans about 11 kilobases, with eight exons and seven introns. Three of the introns contain members of the Alu repeat family. A putative cap site and promoter sequence were identified at the 5' end of the gene. One or two copies of the gene is present in each haploid genome, and no evidence for amplification or polymorphism was obtained.

Study of the levels of expression of two oncogenes, c-myc and c-myb, in acute and chronic leukemias of both lymphoid and myeloid lineage

Total cellular RNA from a series of leukemic cell populations, both myeloid and lymphoid, as well as from normal circulating lymphocytes was analysed for the expression of two cellular oncogenes, c-myc and c-myb, by Northern blot hybridization assay. Expression of c-myc but not of c-myb was observed in unstimulated normal lymphocytes. Stimulation by PHA was shown to activate the expression of both genes. Remarkably different levels of expression of c-myc were observed in ALL, whereas in CLL the expression of c-myc was uniformly low or absent. Differential expression of c-myc was detected in AML as well as in CML, c-myb was differentially expressed in AML and ALL, and absent in CLL and CML. Other single cases of hemopoietic disorders were studied, but the expression of the two oncogenes was low or absent. Neither evident genome amplification nor genome rearrangements were detected in the cell DNAs digested with restriction endonucleases.

Kinetics of hybridization to human DNA of heterogeneous nuclear RNA isolated from normal human lymphoblasts and acute leukemia blast cells

Heterogeneous nuclear RNA was extracted from normal PHA-stimulated human lymphocytes and acute myeloid leukemia blast cells. Experiments were performed to determine the hybridization kinetics of these RNA's to human DNA. The best least squares solutions indicate in the hybridization reaction of both normal and leukemic RNA two main components. For leukemic cell RNA the rate constants of both components were significantly different from that of normal cell RNA. In particular, the difference between the rate constants of the second lower component suggests that the slowly hybridizing sequences in leukemic cell RNA have a degree of repetition higher than of the corresponding sequences of normal cell RNA.

Reassociation kinetics of the DNA of human acute leukemia cells

Human DNA isolated from normal phytohaemagglutinin-stimulated human lymphocytes and from acute leukemia blast cells have been studied by renaturation techniques using hydroxyapatite binding and DNA hyperchromism. In the leukemic genome, the unique sequences account for 62% of the genome of leukemic DNA. Repetitive sequences may be subdivided into at least three fractions: (a) foldback sequences, which represent 5% of the genome; (b) sequences with high repetition frequency (3. 10(4) times on the average), which represent 12% of the genome; (c) sequences with low repetition frequency (10 times on the average), which represent 16% of the genome. The average length of the repetitive sequences is evaluated to be between 200 and 500 nucleotides. There are at least two patterns of interspersion of repetitive sequences with unique sequences of different length: short (about 2000 nucleotides on average) and long (not defined). The results of our experiments on DNA from normal phytohaemagglutinin-stimulated human lymphocytes are in close agreement with those reported by other authors studying different types of human cells. The human leukemic DNA, as far as the parameters that have been studied, does not significantly differ from normal human DNA.

In vitrocleavage of 45S pre-ribosomal RNA and of giant heterogeneous RNA extracted from human leukemic cells

45S ribosomal precursor RNA and large heterogeneous RNA molecules (greater than 45S) extracted from human leukemic cells were incubated in vitro with purified RNase III, which specifically attacks double-helical RNA regions. About 50% of the ribosomal precursor was cleaved into two major fragments sedimenting at 28S and 32S respectively. A limited number of cleavages was also introduced in about 40% of heterogeneous RNA molecules sedimenting faster than 45S, causing a partial 'shift' to a polydisperse distribution in the 10S-45S range.

Immunological assay of double-helical segments in RNA fractions of different molecular size extracted from acute myeloid leukemia blast cells

Whole-cell RNA, extracted from acute myeloid leukemia blast cells, was fractionated by sedimentation through sucrose gradients. The proportion of double-helical segments present in each fraction was then determined by a quantitative microcomplement fixation assay that specifically measures double-helical RNA. Sizable amounts of double-helical segments were detected in all fractions of cellular RNA corresponding to S values higher than approximately 20. In all cell populations examined the highest proportion of double-helical segments was found in RNA fractions sedimenting faster then the 45 S ribosomal precursors RNA, i.e., in fractions including only heterogeneous nuclear RNA.

Accumulation of giant heterogeneous RNA molecules in acute myeloid leukemia blast cells

Time course and "chase" experiments showed that, after incubation of acute myeloid leukemia blast cells with a labeled RNA precursor, a large proportion of radioactivity remained associated with RNA molecules larger than 45 S even after several hr. Double-labeling experiments with [5-3H]uridine and [methyl-14C]methionine indicated that unmethylated giant heterogeneous RNA larger than 45 S is processed much more slowly than the 45 S ribosomal precursor, so that relatively large amounts of fairly stable RNA of the former class accumulate in the cell. The measurement of labeled giant heterogeneous RNA molecules bound to polyuridylate-fiberglass filters showed that molecules carrying polyadenylate segments seemingly turn over faster than those lacking polyadenylate.