CD20 is a surface marker protein of B-cell lymphoma, and its extracellular region is the target of specific antibodies and drugs. To obtain a cheap and easily modified specific preparation targeting CD20, we optimized the gene of CD20 extracellular region according to codon degeneracy to facilitate its expression in Escherichia coli. The optimized gene was cloned into pGEX-4T-1 vector, and the recombinant vector was transformed into E. coli BL21(DE3) for expression. The purified protein was identified by SDS-PAGE and Western blotting. Systematic evolution of ligands by exponential enrichment (SELEX) was employed to screen the ssDNA aptamer that specifically binds to the fusion protein, and the affinity of the aptamer to CD20 was detected by flow cytometry. Then, the cytotoxicity test was carried out to examine the inhibitory effect of the aptamer on B lymphoma cells. In this study, we established the prokaryotic expression method of CD20 and obtained the aptamer specifically binding to the extracellular region of CD20, which laid a foundation for the development of therapeutic drugs targeting CD20.
Humans ; Escherichia coli/metabolism* ; SELEX Aptamer Technique/methods* ; Aptamers, Nucleotide/genetics* ; Antigens, CD20/metabolism* ; Ligands

OBJECTIVETo study the clinicopathologic features and significance of aberrant CD56 expression in diffuse large B-cell lymphoma (DLBCL).

METHODSThe clinical and pathologic profiles of 10 cases of DLBCL with aberrant expression of CD56 were investigated. Immunohistochemical staining, in-situ hybridization for Epstein-Barr virus encoded RNA and gene rearrangement for IgH and Igκ were carried out.

RESULTSThere were 6 male and 4 female patients. The medium age of patients was 46 years. All of them presented with extranodal lymphoma involvement, with gastrointestinal tract being the commonest site (5/10). Histologic examination showed that most of the atypical lymphoid cells were centroblast-like and demonstrated a diffuse growth pattern. Apoptosis and necrosis were identified in some cases. Immunohistochemical study showed that the tumor cells were positive for CD20 or CD79α and aberrantly expressed CD56. Five cases had the GCB phenotype while the remaining cases had the non-GCB phenotype, according to Hans classification. Bcl-6 was positive in most cases (9/10). All cases showed a high proliferation index by Ki-67. The tumor cells were negative for CD3ε, CD138 and granzyme B. In-situ hybridization for Epstein-Barr virus encoded RNA was performed in 7 cases and none of them showed positive signals. IgH gene rearranged bands were detected in 4 cases (4/6) and Igκ was detected in 3 cases (3/6). Follow-up data were available in 8 patients. Two patients died of disease progression within 5 to 13 months after diagnosis and the other 6 patients were alive 8 to 60 months after therapy.

CONCLUSIONSDLBCL with aberrant expression of CD56 is rare. Most of them present with extranodal involvement, show high frequency of bcl-6 expression and high proliferation index. The patients often have good response to chemotherapy.

Antigens, CD20 ; metabolism ; Apoptosis ; CD56 Antigen ; metabolism ; CD79 Antigens ; metabolism ; Disease Progression ; Female ; Gene Rearrangement ; Granzymes ; metabolism ; Herpesvirus 4, Human ; genetics ; Humans ; Immunophenotyping ; In Situ Hybridization ; Lymphoma, Large B-Cell, Diffuse ; genetics ; metabolism ; pathology ; Male ; Middle Aged ; Necrosis ; Phenotype ; Proto-Oncogene Proteins c-bcl-6 ; metabolism ; RNA, Viral ; analysis

Spontaneous gastric perforation is a rare complication of gastric lymphoma that is potentially life threatening since it can progress to sepsis and multi-organ failure. Morbidity also increases due to prolonged hospitalization and delay in initiating chemotherapy. Therefore prompt diagnosis and appropriate treatment is critical to improve prognosis. A 64-year-old man presented to the emergency department with severe abdominal pain. Chest X-ray showed free air below the right diaphragm. Abdominal CT scan also demonstrated free air in the peritoneal cavity with large wall defect in the lesser curvature of gastric lower body. Therefore, the patient underwent emergency operation and primary closure was done. Pathologic specimen obtained during surgery was compatible to diffuse large B cell lymphoma. Fifteen days after primary closure, the patient received subtotal gastrectomy and chemotherapy was initiated after recovery. Patient is currently being followed-up at outpatient department without any particular complications. Herein, we report a rare case of gastric lymphoma that initially presented as peritonitis because of spontaneous gastric perforation.
Abdominal Pain ; Antigens, CD20/metabolism ; Antigens, CD45/metabolism ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; Gastrectomy ; Humans ; Intestinal Perforation/diagnostic imaging ; Lymphoma, Large B-Cell, Diffuse/*diagnosis/drug therapy/pathology ; Lymphoma, Non-Hodgkin/*diagnosis/drug therapy/pathology ; Male ; Middle Aged ; Positron-Emission Tomography ; Stomach Neoplasms/*diagnosis/drug therapy/pathology ; Tomography, X-Ray Computed

The sandwich sign is used to describe mesenteric lymphoma in which mesenteric vessels and fat are enveloped by enlarged mesenteric lymph nodes. We present two cases of primary pleural lymphoma demonstrating the "pleural sandwich sign". Contrast-enhanced computed tomography showed conglomerated parietal pleural and extrapleural masses encasing the intercostal arteries. Histopathological examinations confirmed low grade marginal zone B-cell lymphoma in an 80-year-old man and diffuse large B-cell lymphoma in a 68-year-old man. The pleural sandwich sign may suggest the diagnosis of primary pleural lymphoma.
Aged ; Aged, 80 and over ; Antigens, CD20/metabolism ; Antineoplastic Agents/therapeutic use ; Humans ; Lymphoma, B-Cell, Marginal Zone/*diagnosis/drug therapy/metabolism ; Lymphoma, Large B-Cell, Diffuse/*diagnosis ; Male ; Pleura/*pathology ; Pleural Neoplasms/*diagnosis/drug therapy/metabolism/pathology ; Positron-Emission Tomography ; Tomography, X-Ray Computed

Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal diffuse large B-cell lymphoma that most commonly involves the central nervous system and skin. To our knowledge, no state-of-the art imaging findings have been reported for hepatic IVLBCL in the English literature. We report the first case of hepatic involvement of IVLBCL along with a literature review.
Antigens, CD20/metabolism ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; Humans ; Liver Neoplasms/drug therapy/*pathology/radiography ; Lymphoma, Large B-Cell, Diffuse/drug therapy/*pathology/radiography ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Remission Induction ; Rituximab/administration & dosage ; Tomography, X-Ray Computed

BACKGROUND: Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates. METHODS: A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and kappa and lambda immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology. RESULTS: The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1). CONCLUSIONS: Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.
Antibodies, Monoclonal/immunology ; Antigens, CD19/immunology/metabolism ; Antigens, CD20/immunology/metabolism ; Bone Marrow/*pathology ; Female ; Flow Cytometry ; Humans ; Immunophenotyping ; Lymphoma, B-Cell/*pathology ; Male ; Neoplasm Staging ; Neprilysin/immunology/metabolism

OBJECTIVETo profile the clinicopathologic features of a series of grey zone lymphoma (GZL) cases with hybrid features of diffuse large B-cell lymphoma (DLBCL) and classical Hodgkin lymphoma (CHL), with a purpose to gain an in-depth understanding of the borderline B-cell neoplasm.

METHODSThe clinical, morphologic and immunophenotyical characteristics of 16 cases were retrospectively analyzed.

RESULTSThe patients were mostly male adults, with a male to female ratio of 1.7: 1.0 and a mean age of 40.2 years. Eight patients presented with peripheral nodal lesions and five cases with mediastinal involvement. Histologically and immunophenotypically, the 16 cases were classified into three sub-categories. In 4 cases, the morphologic features resembled CHL more closely, but the neoplastic cells showed uniform and intense positive staining of CD20 (pattern 1). Although the initial impression of the other 8 cases was that of DLBCL, the expression levels of CD20 and PAX5 were variable, and CD30 or CD15 was positive (pattern 2). A characteristic feature of pattern 3, observed in the remaining 4 cases, demonstrated a broad spectrum of morphology with hybrid features of both CHL and DLBCL. The neoplastic cells in pattern 3 were positive for CD20, CD30 and CD15. EBV-LMP1 was detected in 6 of the 11 tested cases. Clinically, most patients with GZL seemed insensitive to immuno-chemotherapy of the R-CHOP regimen.

CONCLUSIONSThe diagnostic criteria for GZL with features intermediate between DLBCL and CHL is proposed by the three histologic patterns commonly seen in these lesions. Cases presented with peripheral lesions might differ from those with mediastinal presentation pathologically. At current time, there is no effective treatment for these borderline B-cell lymphomas and the prognosis is poor.

Adolescent ; Adult ; Aged ; Antibodies, Monoclonal, Murine-Derived ; therapeutic use ; Antigens, CD20 ; metabolism ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Cyclophosphamide ; therapeutic use ; Diagnosis, Differential ; Doxorubicin ; therapeutic use ; Female ; Hodgkin Disease ; drug therapy ; metabolism ; pathology ; Humans ; Ki-1 Antigen ; metabolism ; Lewis X Antigen ; metabolism ; Lymphoma, Large B-Cell, Diffuse ; drug therapy ; metabolism ; pathology ; Male ; Middle Aged ; PAX5 Transcription Factor ; metabolism ; Prednisone ; therapeutic use ; Prognosis ; Retrospective Studies ; Rituximab ; Vincristine ; therapeutic use ; Viral Matrix Proteins ; metabolism ; Young Adult

OBJECTIVETo assess the prognostic value of CD20(+) tumor-infiltrating lymphocytes (TILs) in early-stage breast cancer.

METHODSParaffin sections were collected from 130 cases of stage I-III breast cancer undergoing surgery between January, 2000 and December, 2002 in our hospital. Immunohistochemistry was used to analyze mesenchymal CD20(+) TILs infiltration in the tumor and evaluate its association with the density of CD4(+) and CD8(+) TILs. The association of CD20(+) TILs was evaluated with the histopathologic features, overall survival (OS), distant disease-free survival (DDFS), and disease-free survival (DFS) of the patients.

RESULTSAggregations of CD20(+) lymphocytes were observed in 37.69% (49/130) of the cases. CD3(+) T cells were found to aggregate around CD20(+) B cell aggregations to form lymphoid follicle-like structures. The aggregations of CD20(+) TILs were positively correlated with the densities of mesenchymal CD8+ and CD4(+) TILs. Overall, CD20(+) TIL aggregations were not significantly correlated with the outcomes of the patients, but multivariate COX regressions suggested that CD20(+) TIL aggregations were positively correlated with DDFS (HR=0.251, 95% CI=0.071-0.894, P=0.033) and OS (HR=0.325, 95% CI=0.103-1.028, P=0.056) in hormone receptor-negative patients but not in the positive patients. Further analysis suggested that post-operative adjuvant endocrine therapy significantly improved the OS of patients positive for hormone receptors without CD20(+) TIL aggregations (P=0.001).

CONCLUSIONThe long-term therapeutic effects of adjuvant endocrine therapy are correlated with CD20(+) TIL aggregations to affect prognostic value of CD20(+) TIL aggregations in early-stage breast cancer patients.

Antigens, CD20 ; metabolism ; B-Lymphocytes ; cytology ; Breast Neoplasms ; immunology ; pathology ; Disease-Free Survival ; Female ; Humans ; Lymphocytes, Tumor-Infiltrating ; cytology ; Middle Aged ; Neoplasm Invasiveness ; Prognosis ; Survival Rate

OBJECTIVETo report the diagnosis, differential diagnosis and treatment of a rare case of primary bone marrow CD8+ cytotoxic T-cell lymphoma coexpressed CD20.

METHODSThe clinical characteristics, therapeutic course and the outcome of this patient were reviewed. Meanwhile, a series of examinations including morphology, flow cytometry, immunohistochemistry and molecular biology of bone marrow and skin samples were also performed.

RESULTSBone marrow biopsy showed an extensive involvement by abnormal T lymphocytes. Flow cytometry and immunohistochemistry showed weakly positive CD20, CD8(+), CD2(+), CD3(+), CD5(+), TIA(+), PAX-5(-), CD4(-), CD56(-), CD57(-), CD30(-), ALK-1(-), P53(-), TdT(-), Ki-67≈5%. A final diagnosis of primary bone marrow CD8+ cytotoxic T-cell lymphoma coexpressed CD20 was made. The patient initially presented a relatively indolent course was, but he was expired in the end 3 years later due to extensive involvements of skin and other organs though timely therapy was administrated.

CONCLUSIONPrimary bone marrow CD8 cytotoxic T-cell lymphoma coexpressed CD20 was encountered rarely in clinical practice, which might be a challenging in terms of diagnosis and differential diagnosis. Further investigation of pathogenesis and therapeutic strategies of this rare disease was warranted.

Antigens, CD20 ; metabolism ; CD8-Positive T-Lymphocytes ; metabolism ; pathology ; Humans ; Lymphoma, T-Cell ; diagnosis ; pathology ; Male ; Middle Aged ; T-Lymphocytes, Cytotoxic ; metabolism ; pathology

Adult ; Antigens, CD20 ; metabolism ; Cervical Vertebrae ; pathology ; Eosinophilic Granuloma ; complications ; metabolism ; pathology ; surgery ; Follow-Up Studies ; Hodgkin Disease ; complications ; metabolism ; pathology ; surgery ; Humans ; Ki-1 Antigen ; metabolism ; Male ; Middle Aged ; Spinal Neoplasms ; complications ; metabolism ; pathology ; surgery ; Thoracic Vertebrae ; pathology