Biomedical subjects

L J Medeiros

Publications and source records attributed to L J Medeiros.

At least 19 recordsLinked to original sources

PubMed2006

TCL1 shows a regulated expression pattern in chronic lymphocytic leukemia that correlates with molecular subtypes and proliferative state.

Expression of the human oncogene TCL1 in transgenic mice produces B-cell tumors that resemble chronic lymphocytic leukemia (CLL) suggesting its role in B-cell tumorigenesis. To clarify the expression pattern and regulation of TCL1 in CLL, we assessed 213 primary tumors by immunohistochemistry (IHC), flow-cytometry and/or Western blot, using a new monoclonal antibody. TCL1 protein was detectable in the majority of CLL (90% by IHC) but showed marked variations across cases with virtual absence in approximately 10% of tumors. Higher TCL1 levels correlated with markers of the 'pre-germinal center' CLL subtype including unmutated VH status (P=0.005), ZAP70 expression (P=0.007), and presence of chromosome 11q22-23 deletions (P=0.04). Intratumoral heterogeneity in TCL1 levels was also prominent and explained in part by markedly lower TCL1 expression in proliferating tumor cells. In vitro exposure of CLL cells to interleukin-4 (but not other growth factors) produced progressive and irreversible decrease in TCL1 protein levels in association with the onset of proliferation. TCL1 expression patterns in CLL are complex and highly dynamic and appear to reflect both the histogenetic subtypes of the disease and the growth parameters of individual tumors. The observed regulation pattern suggests that TCL1 may exert its effects predominantly in the unmutated/ZAP70-positive tumor subset.

Animals↗

PubMed2005

p53 gene mutations are uncommon but p53 is commonly expressed in anaplastic large-cell lymphoma.

Anaplastic large-cell lymphoma (ALCL), as defined in the World Health Organization, is a heterogeneous category in which a subset of cases is associated with the t(2;5)(p23;q35) or variant translocations resulting in overexpression of anaplastic lymphoma kinase (ALK). p53 has not been assessed in currently defined subsets of ALCL tumors. In this study, we assessed ALK+ and ALK- ALCL tumors for p53 gene alterations using PCR, single-strand conformation polymorphism and direct sequencing methods. We also immunohistochemically assessed ALCL tumors for p53 expression. Three of 36 (8%) ALCL tumors (1/14 ALK+, 2/22 ALK-) with adequate DNA showed p53 gene mutations. By contrast, p53 was overexpressed in 36 of 55 (65%) ALCL tumors (16 ALK+, 20 ALK-). p21, a target of p53, was expressed in 15 of 31 (48%) ALCL tumors including seven of 15 (47%) p53-positive tumors. p21 expression in a subset of ALCL suggests the presence of functional p53 protein. Apoptotic rate was significantly higher in p53-positive than p53-negative tumors (mean 2.78 vs 0.91%, P = 0.0003). We conclude that the p53 gene is rarely mutated in ALK+ and ALK- ALCL tumors. Nevertheless, wild-type p53 gene product is commonly overexpressed in ALCL and may be functional in a subset of these tumors.

Adult↗

PubMed2004

The activation profile of tumour-associated reactive T-cells differs in the nodular and diffuse patterns of lymphocyte predominant Hodgkin's disease.

AIMS: To compare the activation profile of T-cells in reactive lymphoid follicles with that of tumour-associated T-cells in lymphocyte predominant Hodgkin's disease (LPHD) with a nodular pattern (n = 21), LPHD with partial diffuse growth pattern (n = 11) and T-cell-rich large B-cell lymphoma (TCRLBCL, n = 8). METHODS AND RESULTS: Reactive germinal centres showed sparse numbers of T-cells positive for CD134, a transient/early T-cell activation marker, and only scattered T-cells in the interfollicular areas positive for CD38, a marker of persistent activation. Lymphoid follicles showing progressive transformation of germinal centres (PTGC) had more numerous CD134+ T-cells which were negative for CD38. Tumour-associated T-cells in nodular LPHD were frequently positive for CD134 (15 of 16 cases, 94%), but negative or only focally positive for CD38 (three of 21 cases, 14%). LPHD with diffuse areas, however, showed increased CD38+ T-cells in the diffuse component in 10 of 11 (90%) cases, with CD134+ T-cells being more prominent in the nodular tumour component. TCRLBCL showed strong, uniform CD38 expression in T-cells and histiocytes in eight cases. CONCLUSIONS: T-cells in nodular LPHD express markers of transient/early T-cell activation. By contrast, T-cells in the diffuse form of LPHD, similar to those in TCRLBCL, have an immunostaining profile consistent with persistent cellular activation. T-cell activation may precede or accompany histological progression in nodular LPHD and immunostaining for these markers, in small samples or in difficult cases, may be useful in highlighting those cases of LPHD undergoing histological progression.

ADP-ribosyl Cyclase↗

PubMed2002

Trimetrexate in relapsed T-cell lymphoma with skin involvement.

PURPOSE: Methotrexate (MTX) is active against lymphomas, but transport or polyglutamylation mutations confer MTX resistance. Because trimetrexate (TMTX) enters cells by passive diffusion and is not polyglutamylated, its activity in relapsed T-cell lymphoma was investigated. PATIENTS AND METHODS: Eligible patients had histologically confirmed relapsed T-cell lymphoma involving the skin, had received more than one previous regimen, were older than 16 years, had normal organ function, and had no CNS disease or serious infections, including human immunodeficiency virus. TMTX (200 mg/m(2)) was given intravenously every 14 days without topical or systemic corticosteroids. Patients who responded received up to 12 doses. RESULTS: Twenty patients were assessable for response. Median age was 59 years (range, 45 to 87 years); 13 patients were men. Three patients had anaplastic large-cell lymphoma, 15 had mycosis fungoides or Sézary syndrome (14 with large-cell transformation), and two had peripheral T-cell lymphoma. Serum lactate dehydrogenase was high in 35%, and beta-2 microglobulin was more than 3.0 mg/L in 35% of patients. The median number of previous regimens was three (range, two to 15) and included MTX in five patients. Disease was refractory to the regimen immediately preceding TMTX in 85% of patients. Responses were complete in one and partial in eight patients (overall response rate, 45%). Two of five patients previously treated with MTX responded. Grade 3 or 4 mucositis was observed after 4%, infection after 3%, neutropenic fever after 6%, neutrophils less than 100/microL after 4%, and platelets less than 10,000/microL after 3% of TMTX doses. CONCLUSION: TMTX is active with acceptable toxicity in this population and merits further investigation.

Aged↗

PubMed2002

Establishment and characterization of a new mantle cell lymphoma cell line, Mino.

Mantle cell lymphoma (MCL) is a distinct type of B-cell non-Hodgkin's lymphoma characterized by cyclin D1 overexpression and the cytogenetic abnormality, the t(11;14)(q13;q32). MCL cell lines have been difficult to establish and in vitro studies of these neoplasms are scarce. We describe the establishment and characteristics of a new MCL cell line, Mino. The cells are large, growing singly and in small clumps in vitro. By flow cytometry, the immunophenotype was compatible with MCL (i.e. CD5+CD20+CD23-FMC7+). Conventional cytogenetics showed hyperdiploidy with multiple complex karyotypic abnormalities, but no evidence of the t(11;14), proven to be present only by fluorescence in situ hybridization and polymerase chain reaction (PCR) methods. Western blots showed expression of cyclin D1 but no detectable cyclin D2 and cyclin D3; the retinoblastoma protein was predominantly phosphorylated. There was expression of tumor suppressor gene products including p53, p16(INK4a), and p21(WAF1). Sequencing of the TP53 gene revealed a mutation (codon 147(valine-->glycine)) in exon 5. Epstein Barr virus was absent. In summary, Mino is a new MCL cell line that may be useful to study the pathogenesis of MCL.

Amino Acid Substitution↗

PubMed2002

Is there an increased rate of additional malignancies in patients with mantle cell lymphoma?

PURPOSE: To examine the frequency of additional neoplasms preceding and following the diagnosis of mantle cell lymphoma (MCL). PATIENTS AND METHODS: A total of 156 patients with MCL treated on the hyperfractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone alternated with methotrexate and cytosine arabinoside (Hyper-CVAD/M-A) program with or without rituximab from 1994 to 2000 were the subjects of this report. RESULTS: These patients were followed for a median time of 26 months, and a total of 32 (21%) additional neoplasms were diagnosed, 21 preceding the diagnosis of MCL and 11 following MCL. After excluding certain types of non-invasive neoplasms, including basal cell carcinoma, meningioma and cervical intraepithelial neoplasia, we observed seven second malignancies after the diagnosis of MCL, and the 5-year cumulative incidence rate of second malignancy was 11%. The observed-to-expected (O/E) ratio was 7/0.07 = 100 [95% confidence interval (CI) 49.3 to 186.6; P <0.0001]. Of the 21 malignancies diagnosed prior to MCL, 16 were invasive and five non-invasive. There were a total of 10 urologic malignancies occurring before or after the diagnosis of MCL was established. CONCLUSIONS: Our findings suggest that there is an increased incidence of second malignancies in patients with MCL. In addition, the high number of cases with urinary tract cancer in our series may substantiate prior reports describing a possible association between lymphoma and urologic malignancies.

Adult↗

PubMed2002

Primary cutaneous non-Hodgkin's lymphoma with aggressive histology: inferior outcome is associated with peripheral T-cell type and elevated lactate dehydrogenase, but not extent of cutaneous involvement.

BACKGROUND: The aim of this study was to explore the association between extent of cutaneous involvement, presenting features and progression-free survival (PFS) in patients with primary cutaneous non-Hodgkin's lymphoma (PCNHL) of aggressive histology. METHODS: Previously untreated patients with localized or extensive PCNHL of aggressive histology, treated with combination chemotherapy, but excluding lymphoblastic lymphoma and mycosis fungoides and its variants, were reviewed retrospectively. RESULTS: We identified 53 patients, of whom 52 (35 males, 17 females) were treated with doxorubicin-based regimens. Median age was 52 years (range 25-81 years), and disease was localized and extensive in 37 and 16 patients, respectively. Twenty-four patients had diffuse large B-cell lymphoma, nine had grade 3 follicular lymphoma, 13 had peripheral T-cell lymphoma (PTCL; not otherwise specified) and seven had anaplastic large cell lymphoma (WHO classification). With a median follow-up of 101 months (range 2-237 months) for survivors, the 10-year PFS was 65 +/- 7% and overall survival was 72 +/- 8%. The first failure involved the skin in 33% of B-cell and 91% of relapsing T-cell lymphomas. Univariate analysis revealed that PTCL (P = 0.005), lymphopenia (P = 0.01) and high serum levels of beta(2)-microglobulin (P = 0.0006) and LDH (P = 0.002), but not extent of skin involvement, were associated with inferior PFS. Multivariate analysis revealed that only PTCL and high serum lactate dehydrogenase (LDH) were independently associated with inferior PFS. CONCLUSIONS: PTCL and elevated serum LDH level, but not extent of cutaneous involvement are associated with inferior PFS in aggressive PCNHL treated with combination chemotherapy.

Adult↗

PubMed2002

Irinotecan in relapsed or refractory non-Hodgkin's lymphomas. Indications of activity in a phase II trial.

Because irinotecan (CPT-11, Camptosar) is a topoisomerase I inhibitor with a broad spectrum of antitumor clinical activity, we investigated its activity in relapsed or refractory non-Hodgkin's lymphomas (NHLs). Irinotecan at 300 mg/m2 i.v. was administered every 21 days with intensive loperamide management of diarrhea. Responders received up to six treatment cycles. Of 44 registered patients, 32 are evaluable for response. Seventeen patients had received one previous regimen, and 15 patients had received two. Disease was refractory to the regimen preceding irinotecan in 12 patients. At baseline, serum lactate dehydrogenase levels were high in 47% (14/30), and beta-2-microglobulin levels were higher than 3.0 mg/L in 29% (8/28) of patients. Responses were seen in 12 of 32 (38%) patients (95% confidence interval [CI] = 21%-56%). Response rates were 43% for seven indolent (95% CI = 10%-82%), 0% for three mantle cell (95% CI = 0%-71%), 44% for 18 relapsed aggressive (95% CI = 22%-69%), and 20% for five refractory aggressive NHLs (95% CI = 1%-72%). Grade 3/4 toxicities included myelosuppression, neutropenic fever, and diarrhea. Irinotecan appears active and relatively well tolerated in patients with relapsed aggressive or indolent NHL. Accrual to this study is continuing for better determination of response rates in all histologic subtypes of NHL.

Adult↗

PubMed2001

Primary hepatic lymphoma: favorable outcome after combination chemotherapy.

BACKGROUND: Primary hepatic non-Hodgkin lymphoma (PHL) is a rare and difficult to diagnose lymphoproliferative disorder of unknown etiology. It is believed that the prognosis in affected patients is dismal, consisting of early recurrence and short survival. METHODS: A retrospective cohort review of patients with PHL diagnosed between 1974 and 1995 at a university cancer center was performed. RESULTS: Twenty-four patients with PHL were identified. Typically, the disease occurred in middle-aged men (median age, 50 years). The primary presenting complaint was right upper quadrant abdominal pain, with hepatomegaly found at physical examination. Serum liver enzymes, lactate dehydrogenase, and beta-2-microglobulin levels all were elevated, but alpha-fetoprotein and carcinoembryonic antigen levels were within normal range. Hypercalcemia was found in 6 of 15 patients who were tested. Six of 10 patients who were tested were positive for the hepatitis C virus (HCV). Liver scans demonstrated either a solitary lesion or multiple lesions. Pathologic examination revealed diffuse large cell lymphoma in 23 patients (96%). Combination chemotherapy was the mainstay of treatment; surgery consisted of diagnostic biopsy. The complete remission rate was 83.3%, and the 5-year cause specific and failure free survival rates were 87.1% and 70.1%, respectively. HCV infection did not appear to influence the outcome of therapy. CONCLUSIONS: The outcome of patients with PHL who are treated with combination chemotherapy may be more favorable than that reported elsewhere. The frequent association of PHL with HCV infection observed in this series warrants further investigation.

Adult↗

PubMed2001

Localized non-Hodgkin lymphoma involving the thyroid gland.

BACKGROUND: The current study was undertaken to define the natural history and patterns of failure of localized non-Hodgkin lymphoma (NHL) involving the thyroid gland. METHODS: A retrospective review of 51 patients with Ann Arbor Stage I or II NHL involving the thyroid gland was performed. The median age of the patients was 59 years. There were 33 females. There were 21 patients with Stage I disease and 30 patients with Stage II disease. The International Prognostic Index (IPI) was known for 43 patients (it was 0 in 16 patients and > or = 1 in 27 patients). Fifteen patients had mediastinal involvement. Four patients underwent thyroidectomy, 18 patients received radiation therapy, 5 patients received chemotherapy, and 24 patients received combined modality therapy (CMT) with chemotherapy and radiation therapy. Treatment modality, patient gender, IPI, disease stage, and mediastinal involvement were examined for significance with regard to overall survival (OS) and failure free survival (FFS). RESULTS: The 5-year OS and FFS rates were 64% and 76%, respectively. The 5-year FFS rates by treatment regimen were 76% for radiation therapy, 50% for chemotherapy, and 91% for CMT (P = 0.15). IPI was found to be the only significant predictor of OS. The 5-year OS rates were 86% and 50%, respectively, for IPIs of 0 and > or = 1 (P = 0.02). None of the 5 variables were found to correlate significantly with FFS, although the 5-year FFS rates were 93% and 68%, respectively, for IPIs of 0 and > or = 1 (P = 0.08). Eleven patients failed treatment. Nine patients had a component of distant failure across the diaphragm. CONCLUSIONS: The prognosis of patients with localized NHL involving the thyroid gland appears to be very good, especially when CMT is used. Distant recurrences appear to account for the majority of treatment failures. The IPI was found to be a significant prognostic factor for OS and a marginal one for FFS.

Adolescent↗

PubMed2001

Primary cutaneous non-Hodgkin's lymphoma of Ann Arbor stage I: preferential cutaneous relapses but high cure rate with doxorubicin-based therapy.

PURPOSE: Establish frequency, presenting features, response and relapse patterns, and outcome of primary cutaneous non-Hodgkin's lymphoma (PCNHL). PATIENTS AND METHODS: Review of untreated patients, older than 16 years, presenting between 1971 and 1993 with cutaneous lymphoma, not mycosis fungoides, and Ann Arbor stage I. RESULTS: We identified 46 patients, 27 males, with median age of 57 years. Treatment was radiotherapy in 10 patients, doxorubicin-based therapy in 33 patients that was followed by radiotherapy in 25 patients, and other combination with radiotherapy in one patient. The complete response rate was 95%. After a median follow-up of 140 months (range, 61 to 284 months), 18 patients have relapsed, and 14 have died from lymphoma. The first failure was exclusively cutaneous in 50% of relapses. For the 44 treated patients, progression-free survival (PFS; actuarial +/- SE) was 61% +/- 7% and survival was 58% +/- 9% at 12 years. For the 18 patients with diffuse large B-cell lymphoma, after doxorubicin-based regimens, PFS was 71% +/- 12% (P = .0003) versus 0% after radiotherapy; survival was 77% +/- 12% versus 25% +/- 22% (P = 004), respectively. For the nine patients with follicular center-cell lymphoma treated with combined modality, the 12-year PFS was 89% +/- 11% and survival 70% +/- 18%. CONCLUSION: PCNHL is rare, and its first relapse is exclusively cutaneous in 50% of patients. Patients with diffuse large B-cell lymphoma are curable with doxorubicin-based regimens but not with radiotherapy. Prospective studies in PCNHL should define the cytogenetics, the basis for cutaneous tropism, the prognosis of histologic subtypes, and the role of radiotherapy.

Adult↗

PubMed2001

Orbital mass secondary to precursor T-cell acute lymphoblastic leukemia: a rare presentation.

We describe a 40-year-old woman with a history of precursor T-cell acute lymphoblastic leukemia who developed an orbital mass associated with diffuse infiltration of the paranasal sinuses. The clinical and radiologic findings suggested an orbital abscess. Examination of orbital and ethmoid sinus biopsy specimens revealed relapse of precursor T-cell acute lymphoblastic leukemia. Although orbital involvement by granulocytic sarcoma (also known as extramedullary myeloid cell tumor and chloroma) with or without concurrent acute myeloid leukemia is well described in the literature, similar presence of acute lymphoblastic leukemia of either precursor T-cell or B-cell lineage is rare.

Adult↗

PubMed2001

Differential expression of BCL-2 family proteins in ALK-positive and ALK-negative anaplastic large cell lymphoma of T/null-cell lineage.

Anaplastic large-cell lymphoma (ALCL) of T- or null-cell lineage, as defined in the revised European-American lymphoma classification, includes a subset of tumors that carry the t(2;5)(p23;q35) resulting in overexpression of anaplastic lymphoma kinase (ALK). Patients with ALK+ ALCL are reported to have a better prognosis than patients with ALK- ALCL. Because the mechanisms for this survival difference are unknown, we investigated the hypothesis that apoptotic pathways may be involved. We therefore assessed expression levels of the anti-apoptotic proteins BCL-2 and BCL-XL and the pro-apoptotic proteins BAX and BCL-XS in T/null-cell ALCL using immunohistochemical methods and correlated the findings with ALK expression and apoptotic rate (AR), the latter assessed by a modified Tdt-mediated dUTP nick-end labeling assay. ALK was detected in 21 of 66 (31.8%) ALCLs. BCL-2 was not detected in 21 ALK+ ALCLs but was present in 26 of 45 (57.8%) ALK- ALCLs (P < 0.0001). ALK+ and ALK- ALCLs also showed significant differences in expression of BCL-XL, BAX, and BCL-XS. ALK+ tumors less commonly had a high level of BCL-XL (1 of 17 versus 14 of 35, P = 0.01), and more commonly had high levels of BAX (13 of 18 versus 15 of 36, P = 0.05), and BCL-XS (11 of 16 versus 12 of 31, P = 0.05) compared with ALK- tumors. ALK+ tumors also had a higher mean AR than ALK- tumors (3.4% versus 1.1%, P = 0.0002). Differential expression of BCL-2 family proteins may be responsible for the higher AR observed in ALK+ ALCL and provides a possible biological explanation for the better prognosis reported for patients with ALK+ ALCL.

Adolescent↗

PubMed2001

DNA topoisomerase IIalpha in multiple myeloma: a marker of cell proliferation and not drug resistance.

DNA topoisomerase IIalpha (topo IIalpha) is the target for a number of antineoplastic agents. Down-regulation of this enzyme is one form of drug resistance. Topo IIalpha is also involved in DNA replication and transcription and serves as an indicator of proliferation rate in many human malignancies. This study examines whether topo IIalpha is one of the mechanisms of chemoresistance commonly observed in multiple myeloma (MM) or alternatively, whether topo IIalpha is associated with tumor cell proliferation. Bone marrow (BM) biopsy sections from 72 cases of MM, stratified according to proliferative activity (bromodeoxyuridine uptake), were immunostained for topo IIalpha. Immunoreactivity with an additional marker of drug resistance, glutathione-S-transferase pi, and the proliferation marker Ki-67 were also examined. Topo IIalpha was expressed in 26 (36%) cases and correlated strongly with proliferative activity (P <.001). A role for drug resistance could not be supported, given this strong relationship with proliferation and the finding that glutathione-S-transferase pi expression in 57 (78%) cases was independent of topo IIalpha immunoreactivity. Topo IIalpha was identified in 91 to 100% of highly proliferative tumors, as evaluated by bromodeoxyuridine uptake or Ki-67 reactivity, respectively. Proliferation also correlated with the histologic grade of the MM. Therefore, topo IIalpha immunoreactivity is primarily a marker of cell proliferation in MM and as such is likely to have prognostic significance. Highly proliferative tumors are most likely to be sensitive to chemotherapeutic protocols using anti-topo IIalpha agents.

Adult↗

PubMed2001

Reticulum cell sarcoma of lymph node with mixed dendritic and fibroblastic features.

We report a case of clinically aggressive reticulum cell sarcoma with mixed follicular dendritic cell (FDC) and fibroblastic reticular cell (FRC) features. Histologically, the tumor was confined to lymph nodes occurring as a multifocal epithelioid and spindle cell proliferation with appreciable mitotic rate and numerous admixed non-neoplastic B-cells. Ultrastructural examination revealed elongated cells with prominent nucleoli, interdigitating cell processes and frequent desmosomes. These features are typical of FDC sarcoma. However, immunohistochemical stains showed no expression of antigens characteristic of FDCs, including CD21, CD23 and CD35. Cytogenetic characterization of this tumor, by conventional G-banding and multicolor spectral karyotyping, revealed multiple clonal chromosomal aberrations, including del(X)(p11.4) and add (21)(p11.2). Gene expression analysis by cDNA microarray of RNA obtained from short-term tumor cultures revealed high-level expression of a set of genes (including PDGF receptor-alpha and -beta, certain metalloproteinases, and CD105) that were also highly expressed in cultures of nodal FRC cultured from non-neoplastic lymph nodes. We propose that this tumor represents a nodal sarcoma with intermediate differentiation between FDCs and FRCs. This case adds to the diversity of tumors that may arise from lymph node stroma and supports a possible relationship between the FDC and FRC lineages.

Adult↗

PubMed2001

Ovarian non-Hodgkin's lymphoma: a clinicopathologic study of eight primary cases.

Primary (localized) non-Hodgkin's lymphoma (NHL) of the ovary is rare. We studied eight cases of primary ovarian NHL to better understand the clinicopathologic and immunophenotypic features of these tumors. The patients ranged in age from 29 to 62 years (mean 47 years). Pelvic complaints were the most common symptoms; however, three of eight neoplasms were discovered incidentally. All tumors were unilateral and Ann Arbor stage I(E). The three incidental NHL were microscopic (largest 1.2 cm), whereas the grossly evident lesions ranged from 7.5 to 20 cm (mean 13.3). Each tumor was classified according to the World Health Organization Classification as follows: diffuse large B-cell lymphoma (three cases), follicular lymphoma (two cases), Burkitt lymphoma (one case), T-cell anaplastic large cell lymphoma (one case), and precursor T-lymphoblastic lymphoma (one case). Six tumors were of B-cell lineage, and two tumors were of T-cell lineage. All three diffuse large B-cell lymphomas were positive for BCL-6, two were positive for CD10, and two were positive for BCL-2. Estrogen and progesterone receptors were negative in all NHLs assessed. Patients were treated by various combinations of surgery, chemotherapy, and radiotherapy. Clinical follow-up ranged from 1.3 to 11.7 years (mean 5.2) and all patients were alive without disease at last follow-up. We conclude that most patients with primary ovarian NHL present with symptoms attributable to an ovarian mass, but in a subset of patients ovarian NHL may be detected incidentally. With appropriate therapy, patients appear to have a favorable prognosis although follow-up is short for some patients in this study.

12E7 Antigen↗

PubMed2001

Leukemic mantle cell lymphoma: clinical and pathologic spectrum of twenty-three cases.

Twenty-three patients with marked leukemic involvement by mantle cell lymphoma (MCL) are described. Each patient had an absolute lymphocyte count more than 10 x 10(9)/L. The diagnosis of MCL was supported by compatible immunophenotypic findings and the t(11;14)(q13;q32) in all cases. Morphologically, these cases exhibited a spectrum of findings that we divided into two groups using a cutoff of 20% large or blastoid cells (log rank test, P =.004). Patients with small-cell (<20%) morphologic features survived longer than patients with large/blastoid (> or =20%) morphologic features, (P =.003, log rank test). The most common additional karyotypic abnormality identified in this study involved chromosome 17, in 13 of 23 (56.5%) cases, which correlated with p53 overexpression but not with cytologic features. We conclude that cytologic features of MCL predict the prognosis of patients with marked leukemic involvement. Chromosome 17 abnormalities are common in leukemic MCL, may be involved in pathogenesis, and are associated with p53 expression.

Adult↗

PubMed2001

Cyclin D1 and E2F-1 immunoreactivity in bone marrow biopsy specimens of multiple myeloma: relationship to proliferative activity, cytogenetic abnormalities and DNA ploidy.

Cyclin D1, encoded by the CCND1 gene, is immunohistochemically detectable in up to one-third of cases of multiple myeloma (MM). To examine the mechanism of cyclin D1 overexpression, we compared cyclin D1 immunoreactivity with the results of conventional cytogenetics to determine if the t(11;14)(q13;q32) or other abnormalities of 11q11-14 explained cyclin D1 overexpression. Karyotypic abnormalities were found in 45 out of 67 (67%) MM cases; the t(11;14) was present in seven cases (10%). Additional 11q11-14 abnormalities were not identified. The t(11;14) correlated with cyclin D1 upregulation in low to intermediately proliferative MM, but was not present in highly proliferative tumours (assessed using bromodeoxyuridine labelling index). Cyclin D1 indirectly activates the transcription factor E2F-1. In the bone marrow biopsy specimens of MM cases, E2F-1 was concurrently expressed with cyclin D1 (P = 0.001), indicating that cyclin D1 is functional. However, as neither E2F-1 nor cyclin D1 expression correlated with proliferative activity, the speculation that t(11;14) upregulates the CCND1 gene to induce higher proliferation and possibly more aggressive disease is not supported. We conclude that in low to intermediately proliferative MM cases, cyclin D1 is probably upregulated by t(11;14), but an alternative mechanism is more probable in highly proliferative MM.

Adult↗