Cytogenetic findings in 175 patients indicate that items of the Kiel classification should not be disregarded in the REAL classification of lymphoid neoplasms

The Spectrum of Lymphoma with 8q24 Aberrations: A Clinical, Pathological and Cytogenetic Study of 87 Consecutive Cases

To define the histologic, cytogenetic (CG) and clinical spectrum of non-Hodgkin lymphoma (NHL) carrying an 8q24 (c-myc) translocation, 87 patients with an 8q24 aberration were identified from 785 consecutive successfully analyzed cases. Aberrations involving 8q24 were found at diagnosis (n = 66) or at relapse/progression (n = 21). Histologically, Burkitt-like lymphoma (BLL) (32%) and Burkitt's leukemia/lymphoma (BL) (19%) with 8q24 changes at diagnosis, was the most common. Nevertheless, 46% of cytogenetically characterized BL and BLL cases do not show 8q24 aberrations. On the other hand, 8q24 aberration was also often found in follicular lymphoma (FL), mantle cell lymphoma (MCL) and low-grade NHL cases at progression. Cytogenetically, a de novo group is represented by classical t(8;14)(q24;q32) (n = 41), with isolated 8q24 changes, fewer secondary CG changes and represent mostly BL/BLL cases. In contrast, cases carrying variant 8q24 aberrations (n = 29) contain more CG events, carried primary 14q32 translocations, and included most FL, MCL and diffuse large B cell (DLBC) lymphoma cases. Clinically, the overall median follow-up was 8.6 months (range 0-192), with a median survival of 4.2 months from CG analysis. The presence of a 8q24 aberration give a statistically significant inferior prognosis than its absence in all histological groups, independent of clinical prognostic factors, when analyzed both at diagnosis and at relapse. We conclude that the finding of an 8q24 aberration is of marked negative prognostic significance, either at diagnosis or at disease progression, in a variety of NHL.

Additional cytogenetic abnormalities in adults with Philadelphia chromosome-positive acute lymphoblastic leukaemia: a study of the Cancer and Leukaemia Group B

We analysed the nature and prognostic significance of secondary cytogenetic changes in 111 newly diagnosed adults with acute lymphoblastic leukaemia (ALL) and t(9;22)(q34;q11.2) or its variants. Secondary aberrations were seen in 75 (68%) patients. They included, in order of descending frequency: +der(22)t(9;22), +21, abnormalities of 9p, high hyperdiploidy (>50 chromosomes), +8, -7, +X and abnormalities resulting in loss of material from 8p, gain of 8q, gain of 1q and loss of 7p. Eighty patients (72%) had > or =1 normal metaphase in their karyotype. There were four balanced and 12 unbalanced translocations previously unreported in ALL with t(9;22). The t(2;7)(p11;p13) and der(18)t(8;18)(q11.2;p11.2) were seen in two cases each, and have never before been reported in haematological malignancy. All but four patients were treated on front-line Cancer and Leukaemia Group B clinical protocols. The presence of -7 as a sole secondary abnormality was associated with a lower complete remission (CR) rate (P = 0.004), while the presence of > or =3 aberrations was associated with a higher CR rate (P = 0.009) and +der(22)t(9;22) with a higher cumulative incidence of relapse (P = 0.02). It will be of interest to see if newly diagnosed t(9;22)-positive adult ALL patients with these and other secondary aberrations respond differently to treatment regimens that include imatinib mesylate.

Cytogenetic analysis in mantle cell lymphoma: a review of 214 cases

Cytogenetic (CG) analysis was performed in 78 consecutive cases of mantle cell lymphoma (MCL) at the British Columbia Cancer Agency (BCCA). A clone containing a t(11;14) translocation was identified in 53 cases. Data from 47 cases with sufficient CG details were reviewed along with 167 cases of t(11; 14)-associated lymphoproliferative diseases (LPD) from the literature. Common aneuploidies included -Y, -13, -9, -18, +3 and +12. Common structural changes included: +3q, +12q, del(6q), del(1p), del(13q), del(10q), del(11q), del(9p) and del(17p). The commonest breakpoints clusters were 1p21-22, 1p31-32, 1q21, 6q11-q15, 6q23-25, 8q24, 9p21-24, 11q13-23, 13q12-14, and 17p12-13. When analyzed separately as lymph node-based disease (LN group) and peripheral blood disease (PB group), deletions and chromosomal losses were more common in the LN group, while gains of chromosome segments 3q and 12q were similar. The LN group was cytogenetically more complex. CG analysis is useful for confirming the diagnosis of MCL. Almost all cases will have t(11; 14), but poor quality and number of metaphases may render a difficult analysis. CG evolution in MCL follows a complex but defined pattern. Regions affected by recurrent changes are similar to other B cell lymphomas. The LN and PB groups of t(11;14)-associated LPD may have subtle differences in clonal evolution.

Dietary l-carnitine stimulates carnitine acyltransferases in the liver of aged rats

Aging affects oxidative metabolism in liver and other tissues. Carnitine acyltransferases are key enzymes of this process in mitochondria. As previously shown, the rate of transcription and activity of carnitine palmitoyltransferase CPT1 are also related to carnitine levels. In this study we compared the effect of dietary l-carnitine (100 mg l-carnitine/kg body weight/day over 3 months) on liver enzymes of aged rats (months 21-24) to adult animals (months 6-9) and age-related controls for both groups. The transcription rate of CPT1, CPT2, and carnitine acetyltransferase (CRAT) was determined by quantitative reverse transcription real-time PCR (RTQPCR) and compared to the activity of the CPT1A enzyme. The results showed that the transcription rates of CPT1, CPT2, and CRAT were similar in aged and adult control animals. Carnitine-fed old rats had a significant (p<0.05) 8-12-fold higher mean transcription rate of CPT1 and CRAT compared to aged controls, adult carnitine-fed animals, and adult controls, whereas the transcription rate of CPT2 was stimulated 2-3-fold in carnitine-fed animals of both age groups. With regard to the enzymatic activity of CPT1 there was a 1.5-fold increase in the old carnitine group compared to all other groups. RNA in situ hybridization also indicated an enhanced expression of CPT1A in hepatocytes from l-carnitine-supplemented animals. These results suggest that l-carnitine stimulates transcription of CPT1, CPT2, and CRAT as well as the enzyme activity of CPT1 in the livers of aged rats.

Secondary chromosome changes in mantle cell lymphoma: cytogenetic and fluorescence in situ hybridization studies

To better define the incidence and nature of secondary chromosome anomalies in mantle cell lymphoma (MCL) carrying the t(11:14)/BCL1 rearrangement, cytogenetic and fluorescence in situ hybridization studies (FISH) were performed in 42 patients (39 classical histology, 3 blastoid variant), using 6q21, 9p21/p16, 13q14, 17p13/p53 and chromosome-12-specific probes. Karyotypes from 89 cases published in 5 recent series including patients diagnosed in a homogeneous fashion were reviewed. In our series, FISH confirmed the interpretation of the karyotype in all cases and disclosed cryptic chromosome deletions in a sizeable fraction of cases. One patient (2.4% of total) was found with a cryptic 9p21 deletion by FISH. Two cases (4.8%) had a 6q21 deletion at CCA and at FISH; +12 was found in three cases by CCA plus nine by FISH (28.6%); 13q14 deletion was found in six cases by CCA plus 16 by FISH (52.4%), 17p13 deletion in three cases by CCA plus 8 by FISH (26.2%). In 131 patients (42 present series plus 89 in the literature) secondary chromosome aberrations seen by conventional cytogenetic analysis in more than 5 cases included deletions/translocations (del/t) 6q15-23 [15 cases]; -13 [14 cases]; del/t 1p21-31 [12 cases]; +3q [11 cases]; del/t 17p [9 cases]; 8p translocations and del(Y) [8 cases each]; -20 [7 cases]; 13q14 deletion, del/t 11q22-23, del/t 9q, del(10)(q22q24), -20, -21, -22 and -X [6 cases each]. We arrived at the following conclusions: i) though no secondary anomaly is specific for MCL, there is a distinct profile of recurrent chromosome lesions in MCL with 1p21-31 deletions, 8p translocations, 11q22-23 anomalies having a strong association with CD5+ B-cell lymphomas of low-to-intermediate grade histology; ii) FISH enabled the detection of cryptic chromosome 12, 13q and 17p rearrangements in a sizeable fraction of cases; iii) 9p21/p16 deletions did not occur at a high incidence in this series, possibly because of the low number of cases with blastoid variant.

Association of GB virus C (GBV-C)/hepatitis G virus (HGV) with haematological diseases of different malignant potential

Among risk groups for GB virus C (GBV-C)/HGV infection, patients with haematological diseases are particularly exposed due to the combination of transfusional support and immunodeficiency status. To examine any association between GBV-C/HGV positivity and different malignancy potential of hematological diseases, we investigated two groups of patients, one with clonal stem cell disease with long latency period (myelodysplasia, myeloproliferative disease) and one with malignant haematological diseases (Hodgkin's lymphoma, non-Hodgkin's lymphoma, acute leukemia, multiple myeloma). Virus positivity was compared with the data from cytogenetic analysis at first diagnosis. The frequency of GBV-C/HGV infection in these patients was studied using reverse transcription-polymerase chain reaction (RT-PCR) and E2 antibody assay. Serum GBV-C RNA was found in 29/47 (62%) patients. The prevalence of GBV-C RNA in the group of oncological cases (72%) was significantly higher (P= .02) than in the patients with clonal stem cell diseases (28%). Among the GBV-C negative cases, only 25% had malignant haematological diseases. The data from GBV-C/ HGV tested cases for which cytogenetic analysis was carried out indicated an association of GBV-C/HGV positivity with genomic destabilization in general. Of the cases with numerical and structural aberrations, 64% were GBV-C positive. A correlation could not be confirmed between GBV-C/HGV and liver enzyme levels, blood transfusions, chemotherapy treatment, or viral coinfection. These findings suggest a high risk of GBV-C/HGV infection in patients with haematological disorders especially in the group of malignant diseases. These observations may indicate that the persistence of GBV-C/HGV in these patients could be associated with susceptibility to genomic destabilisation.

Gain of 3q and deletion of 11q22 are frequent aberrations in mantle cell lymphoma

We used comparative genomic hybridization (CGH) to screen for DNA copy number changes in 34 specimens from 27 cases of mantle cell lymphoma (MCL). The most common gains were detected at 3q (52%), 8q (30%), and 15q (26%), whereas the most frequent losses involved 13q (41%), 1p (33%), 6q (30%), 9p (30%), and 11q (30%). The gain of 3q, with a minimal common region at 3q26.1-27, appeared in more than half of the lymphomas, suggesting the location of an important oncogene here. A common deleted region at 11q22 was found in one-third of the patients, which suggests that this region may harbor a tumor suppressor gene important in the tumorigenesis of MCL. The mean number of changes was higher in more aggressive blastoid variants of MCL than in lymphomas with typical morphology. Our results show that the chromosomal regions affected in MCL are highly consistent and are different from those seen in other types of non-Hodgkin's lymphoma.