Hyperphosphorylation of CD20 in hairy cells. Alteration by low molecular weight B cell growth factor and IFN-alpha.

Hairy cell leukemia (HCL) is a B cell tumor affecting the pre-plasma stage of B cell differentiation. Hairy cells produce B cell growth factor (BCGF)-related growth factor(s) and we have previously shown that low mol wt (LMW)-BCGF-induced proliferation of hairy cells is inhibited in vitro and in vivo by IFN-alpha. We therefore suggested that this effect might contribute to the exquisite sensitivity of HCL to IFN-alpha therapy. To elucidate the mechanism involved in the therapeutic effect of IFN-alpha, we have analyzed the pattern of phosphorylated proteins in hairy cells. We detected the presence of a hyperphosphorylated protein with a molecular mass of about 35 kDa. This protein was identified as the CD20 molecule (B1), which is a structurally unique phosphoprotein exclusively detected on B cells and expressed during most stages of B cell development. Incubation of hairy cells with mitogenic concentrations of LMW-BCGF induces an additional increase in CD20 protein phosphorylation. In contrast, preincubation of cells with IFN-alpha, but not IFN-gamma, decreases both basal and LMW-BCGF-induced CD20 phosphorylation. CD20 phosphorylation in hairy cells is also reduced after in vivo IFN-alpha administration. In contrast, in one case of a patient unresponsive to IFN-alpha therapy, CD20 phosphorylation is not altered by in vitro IFN-alpha treatment, whereas LMW-BCGF still elicits CD20 phosphorylation stimulation. Our results suggest that IFN-alpha may act in HCL, at least in part, by inhibiting leukemic cell proliferation via regulation of phosphorylation, since CD20 phosphorylation is thought to be associated with cellular proliferation. A model involving dysregulation of CD20 is discussed.     

Hairy cell leukemia associated with carcinoma: report of two patients and review of the literature

The association of carcinoma and hairy cell leukemia (HCL) in two patients is recorded. One of the cases was a 58-year-old male who developed carcinoma of the kidney, while the second patient was a 48-year-old woman with carcinoma in the breast. This rare association is probably coincidental, as it is not described in most of the larger reported series of patients with HCL. It is of interest to note that the first patient had received radiation therapy thirty years before the diagnosis of HCL and carcinoma was made.     

Cytologic detection of malignant lymphoma cells with a hairy appearance in ascitic fluid. Report of a case with immunofluorocytometric analysis

Neoplastic lymphocytes with a hairy appearance were detected in the ascitic fluid from a case of retroperitoneal malignant lymphoma. Although the tumor cells resembled those of hairy-cell leukemia (HCL), no leukemic change was observed, and the anatomic location of the neoplastic cells was different from that seen in HCL. The tumor cells were positive for some immunohistochemical markers of HCL (i.e., CD1 9 and SIg) but were negative for others (CD11c, CD25 and tartrate-resistant acid phosphatase). Immunocytofluorometric and postmortem histologic studies showed the lesion to be a well-differentiated B-cell lymphocytic lymphoma with plasmocytic differentiation in some cells.     

Characterization of T-cell repertoire in hairy cell leukemia patients before and after recombinant immunotoxin BL22 therapy

We previously reported that hairy cell leukemia (HCL) patients have high percentages of CD56+/CD57+/CD3+ large granular lymphocytes consistent with cytotoxic T-lymphocytes (CTLs), and other investigators have reported skewing of the T-cell repertoire. In previous studies of up to seven HCL patients, many of the 22 established T-cell receptor (TCR) beta variable region (TRBV) families showed mono- or oligoclonal restriction. To determine whether percentages of CTLs are correlated with TRBV clonal excess, we studied 20 HCL patients with flow cytometry, PCR of TCR gamma and TRBV regions, and fractional gel electrophoresis of PCR-amplified TRBV CDR3 domains (CDR3 spectratyping). Increased percentages of CD3+/CD8+/CD57+ CTLs correlated with more mono/oligoclonal and fewer polyclonal TRBV families (r=0.53; P=0.016). Age correlated with number of mono/oligoclonal TRBV families (r=0.51; P=0.022). Time since last purine analog therapy correlated with number of polyclonal TRBV families (r=0.46; P=0.040), but treatment with the anti-CD22 recombinant immunotoxin BL22 was not related to clonal excess. We conclude that abnormalities in the T-cell repertoire in HCL patients may represent deficient immunity, and may be exacerbated by purine analogs. Increased CD3+/CD57+ T-cells may be a useful marker of abnormal TRBV repertoire in HCL patients, and might prove useful in deciding whether patients should receive biologic antibody-based treatment rather than repeated courses of purine analog for relapsed disease.     

Morphological and immunological changes of hairy cell leukemia during alpha-2-interferon therapy

We describe a patient who presented with the clinical picture of hairy cell leukemia (HCL). Bone marrow and peripheral blood lymphoma cells showed morphological and immunological features of HCL. Under recombinant alpha-2-interferon (alpha-2-IF) therapy the characteristic morphology changed from HCL to prolymphocytic leukemia (PLL). At diagnosis the lymphoma cells expressed CD24 and FMC7 surface antigen, but stained negative for surface immunoglobulins, light chains and anti-CD5. During alpha-2-IF treatment surface antigen expression changed to CD24, CD5 and FMC7. Surface IgD and lambda light chains became strongly positive. Southern Blot analysis of peripheral blood mononuclear cells showed two rearranged immunoglobulin bands at diagnosis but only one upon alpha-2-IF therapy. These data suggest, that this patient suffered from a biclonal lymphoma, HCL and PLL. While undergoing alpha-2-IF treatment the HCL came into remission, whereas the PLL clone proved to be poorly sensitive to alpha-2-IF therapy.     

Oxysterols induce transition of monocytic cells to phenotypically mature dendritic cell-like cells

Dendritic cells (DCs) activate adaptive immune responses in atherosclerotic plaques; however, the origin of DCs is in question. We attempted to determine whether cholesterol or its oxide forms, which are detected in abundance in atheromatous lesions, could induce differentiation or transition of monocytic cells to DCs. Treatment of THP-1 cells with 27-hydroxycholesterol (27OH-Chol) and 7α-hydroxycholesterol (7αOH-Chol) resulted in an increase in the numbers of adherent cells, and, in contrast to PMA, decreased uptake of FITC-conjugated dextran. In addition, treatment with 27OH-Chol and 7αOH-Chol induced expression of mDC-specific molecules, including CD40, CD80, CD83, and CD88. Of the two oxysterols, 27OH-Chol enhanced expression of MHC class I and II molecules as well as CCR7. However, treatment with an identical concentration of cholesterol and 7-ketocholesterol did not influence adherence, uptake of FITC-conjugated dextran, and expression of the aforementioned molecules. This is the first study to report on change of monocytic cells by oxysterols to phenotypically atypical cells with some characteristics of mDCs detected in atherosclerotic lesions. We propose that a certain type of oxysterol would contribute to immune responses in atherosclerotic lesions by enhancing expression of multiple CD molecules as well as MHC molecules by monocytic cells.     

Hairy cell leukaemia with unusual BRAF mutations

Hairy cell leukaemia (HCL) diagnosis is based on the morphologic detection of circulating abnormal hairy cells in the peripheral blood and/or bone marrow, an HCL immunological score of 3 or 4 based on the expression of the CD11c, CD25, CD103 and CD123 and also the presence of a BRAF V600E activating mutation in the B-raf proto-oncogene (BRAF gene) (7q34). When using new generation sequencing of 21 targeted genes in 124 HCL patients, we identified a cohort of 6/124 (2%) patients with unusual BRAF mutations: two patients presented non-V600 mutations (BRAF F595L, BRAF W604L respectively) and four other patients silent BRAF mutations. When using droplet digital PCR (ddPCR) three of the four patients with concomitant BRAF V600E and silent mutation were negative. The respective role of these mutations in the occurrence of HCL or its progression remains to be clarified, but BRAF sequencing is necessary in case of negative BRAF V600E by ddPCR.     

Phenotypic modulation of chronic lymphocytic, prolymphocytic, and lymphoplasmacytic leukemia cells by TPA: induction of TRAP isoenzyme 5 and HD6 (CD22) antigen and enhancement of IgM messenger RNA

B-cell neoplasias such as CLL can be viewed as models of monoclonal populations restricted within discrete ranges of B-cell maturation. It is unknown whether other B-cell leukemias such as prolymphocytic leukemia (PLL), lymphoplasmacytoid immunocytoma (IC), and hairy cell leukemia (HCL) involve different B lineages or are malignant variants of B cells in successive stages of development along the same lineage. Therefore in vitro maturation was induced with the phorbol ester TPA in leukemic cell samples from 10 CLL, 4 PLL, and 4 IC patients. Morphologically, both plasmacytic and hairy cell-like phenomena were induced. The latter unexpected finding was confirmed by reaction with HD6 (CD22) antibody which stains HCL but is unreactive with plasma cells, multiple myeloma, and CLL cells. Tartrate-resistant acid phosphatase was demonstrated in TPA-cultured CLL, PLL, and IC cells, and the same isoenzyme band as in HCL was revealed by isoelectrofocusing. On the other hand, an increase of IgM messenger RNA was detected in up to 20% of the cells in CLL cultures by single-cell in situ hybridization with fluoro-chrome-labeled DNA probes. An abundance of IgM messenger RNA characterizes lymphoplasmacytoid cells as found in IC. Our data demonstrate that CLL, PLL, and IC can be induced to realize a common genetic program which bears characteristics of HCL indicating that these four entities are more closely related than previously thought.     

A gastrointestinal stromal tumor (GIST) masquerading as an ovarian mass

Background

Malignant gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors originating in the wall of the gastrointestinal tract. Myogenic gastrointestinal stromal tumor, a distinctive morphologic variant is characterized by an unusually prominent myxoid stromal background.

Case presentation

We report a case of myxoid variant of GIST in a 42 years old woman presenting as an epigastric mass associated to an ovarian cyst and elevated CA-125. Histologically, the lesions was composed of a proliferation of spindle cells in an abundant myxoid stroma, without evidence of atypia or anaplasia. Immunohistochemical stains showed strong positive staining with muscle actin, positive staining with CD34 and weak positive staining with CD117, while showed negative for S-100.

Conclusion

At surgery every effort should be made to identify the origin of the tumor. A complete surgical removal of the tumor should be obtained, as this is the only established treatment that offers long term survival.     

Phenotyping of circulating CD8⁺ T cell subsets in human cutaneous leishmaniasis

Recovery from CL is usually accompanied with long-lasting protection and induction of strong immune response. The phenotypes, generation and maintenance of central (=T_CM) and effector (=T_EM) memory T cell subsets in human leishmaniasis are not well known. Profile of T cell subsets were analyzed on peripheral CD8⁺ T cells from volunteers with history of cutaneous leishmaniasis (HCL).In HCL and control groups, mean frequencies of CCR7⁺CD45RA⁺CD8⁺ naïve and CCR7^?CD45RA^?CD8⁺ T_EM cells were higher than other subsets before culture, but after stimulation with soluble Leishmania antigen, the frequency of naïve T cells was significantly decreased and the frequency of T_EM cells was significantly increased. T_EM phenotype composed the highest portion of proliferating Carboxy Fluorescein diacetate Succinimidyl Ester (CFSE)-dim population which was significantly higher in HCL volunteers than in control group. Stimulation of isolated CD8⁺ memory T cells, but not naïve T cells, from HCL volunteers induced a significantly higher IFN-γ production compared with that of healthy controls. Intracellular IFN-γ staining provided the same result.Memory population is shown to be responsible for Leishmania-induced IFN-γ production. Leishmania-reactive proliferating T_EM cells were identified as the most frequent subset which may play a role in recall immune response and protection against Leishmania infection.     

<Emphasis Type="Italic">Paracoccidioides brasiliensis</Emphasis> Infection Mimicking Recurrent Hodgkin Lymphoma: A Case Report and Review of the Literature

Paracoccidioides infection is a rare entity in the USA. This dimorphic fungus is found in Central and South America and is thought to be acquired by inhalation through the soil. We report a case of Paracoccidioides brasiliensis infection presenting as a clavicular bone lesion, peripancreatic mass, and various skin lesions. A 35-year-old man with a history significant for Hodgkin lymphoma presented with a left clavicular mass that was suspected clinically and radiologically as recurrent Hodgkin lymphoma. He was not experiencing any associated symptoms and was undergoing chemotherapy treatment for his known Hodgkin disease. On CT imaging, the mass was seen as a lytic bone lesion with an overlying soft tissue mass. This was biopsied and histologically diagnosed as a Paracoccidioides brasiliensis infection with associated necrotizing granulomatous inflammation. Also found on the CT scan was an enlarging peripancreatic mass which on endoscopic biopsy had similar histologic findings. In conclusion, this report presents a rare case of Paracoccidioides brasiliensis infection mimicking recurrent Hodgkin lymphoma.     

Uterine adenocarcinoma with generalised metastasis in a bottlenose dolphin Tursiops truncatus from northern Patagonia,Argentina

An endometrial adenocarcinoma with areas of squamous differentiation and generalised metastasis was observed in a bottlenose dolphin Tursiops truncatus stranded in northern Patagonia in July 1997. This is the second report of a uterine adenocarcinoma in a free-living cetacean and the first in a Delphinidae. This neoplasm likely compromised reproduction for several years. In addition, the dolphin presented tattoo-like skin lesions and its digestive tract was infested by Anisakis simplex, Pseudoterranova sp., Braunina cordiformis and Corynosoma australe.     

Growth hormone deficiency and replacement in patients with treated Cushing's Disease, prolactinomas and non-functioning pituitary adenomas: effects on body composition, glucose metabolism, lipid status and bone mineral density

BACKGROUND/AIMS: This study was designed to determine whether previous Cushing's disease (CD) or prolactinoma (PRL) could exert adverse effects additional to those of growth hormone (GH) deficiency as a consequence of variable degrees of prior hypogonadism or hypercatabolism. We report the effects of 5 years GH treatment in 124 GH deficiency adults; 42 patients with non-functioning pituitary adenomas (NFPA), 43 with treated PRL and 39 with treated CD. METHODS: Fasting plasma glucose, HbA(1c), lipoprotein profile, anthropometry and bone mineral density (BMD) were measured at baseline, 6 months and annually up to 5 years. RESULTS: Mean body mass index remained unchanged in the PRL group and tended to increase in the NFPA group. In contrast, body mass index decreased in the CD group. Decreases in waist and waist/hip ratio were seen in all groups at 6 months. Decreases in total cholesterol and low-density lipoprotein cholesterol were seen in all groups and remained sustained at 5 years. Plasma glucose and HbA(1c) increased at 6 months. Subsequently, plasma glucose returned to baseline values at 5 years; in contrast, HbA(1c )remained unchanged at the end of the study. Baseline lumbar spine and hip BMD were lower in the PRL and CD groups than in the NFPA group, decreased over 1 year in all groups and subsequently increased by 2 years in NFPA with a subsequent increase in lumbar spine BMD in PRL and CD groups delayed to 3-5 years. CONCLUSIONS: Baseline characteristics and response to GH replacement are qualitatively similar in NFPA, PRL and CD patients. Because improvements in BMD occur later in PRL and CD patients, an extended trial of GH therapy may be indicated in those patients who were commenced on GH therapy as an additional treatment for reduced BMD.     

Peripheral calcifying cystic odontogenic tumour of the maxillary gingiva

ABSTRACT: BACKGROUND: Odontogenic tumors are lesions that are derived from remnants of the components of the developing tooth germ. The calcifying cystic odontogenic tumor or calcifying odontogenic cyst is a benign cystic neoplasm of odontogenic origin that is characterized by an ameloblastoma-like epithelium. Calcifying cystic odontogenic tumor may be centrally or peripherally located, and its ghost cells may exhibit calcification, as first described by Gorlin in 1962. Most peripheral calcifying cystic odontogenic tumors are located in the anterior gingiva of the mandible or maxilla. CASE PRESENTATION: Authors report a rare case of a peripheral calcifying cystic odontogenic tumor of the maxillary gingiva. A 39-year-old male patient presented with a fibrous mass on the attached buccal gingiva of the upper left cuspid teeth. It was 0.7-cm-diameter, painless and it was clinically diagnosed as a peripheral ossifying fibroma. After an excisional biopsy, the diagnosis was peripheric calcifying cystic odontogenic tumor. The patient was monitored for five years following the excision, and no recurrence was detected. CONCLUSIONS: All biopsy material must be sent for histological examination. If the histological examination of gingival lesions with innocuous appearance is not performed, the frequency of peripheral calcifying cystic odontogenic tumor and other peripheral odontogenic tumors may be underestimated.     

Genomic profiling of plasmablastic lymphoma using array comparative genomic hybridization (aCGH): revealing significant overlapping genomic lesions with diffuse large B-cell lymphoma

Background

Cholestatic jaundice as a presenting symptom of Precursor T-lymphoblastic leukemia (T-ALL)/lymphoma (T-LBL) has never been reported in literature. Similarly, precursor T-ALL/T-LBL is characteristically negative for synaptophysin. We report the first case of a patient with precursor T-ALL/T-LBL who presented with cholestatic jaundice and aberrant tumor expression of synaptophysin.

Case report

42 year old male presented with anorexia, nausea, jaundice, pale stools, dark urine and about 35 pound weight loss over the previous 3 weeks. The initial laboratory work was suggestive of cholestatic jaundice. Markedly elevated LDH (2025 U/L) and CA 19-9 (1778 u/ML) were also noticed. The CT scan of abdomen showed massive hepatomegaly with coarse echotexture with contracted gall bladder and normal sized common bile duct. Chest x-ray revealed a mediastinal mass with mediastinal widening. CT scan of the chest showed anterior mediastinal mass (16 cm × 10 cm). CT guided biopsy of the mass showed malignant lymphoma with diffuse proliferation of medium sized lymphoid cells. The neoplastic cells were positive for CD1a, CD3, CD4, CD5, CD8 and CD43 with aberrant expression of synaptophysin. PET CT scan again showed a large anterior mediastinal mass with diffuse liver involvement and abnormal activity in axial bones. CT guided liver biopsy and bone marrow biopsy revealed the same morphology and immunohistochemistry. Bone marrow aspirate showed 85% lymphoblasts. Thus, the diagnosis of precursor T-ALL/T-LBL was made and jaundice with elevated CA 19-9 were attributed to intrahepatic cholestasis.

Conclusion

Our case illustrates an unusual presentation of hematological malignancies as cholestatic jaundice. It also indicates the non-specific nature of CA 19-9 for pancreaticobiliary malignancies. It is the first case report of neoplastic precursor T cell lymphoblasts with unusual expression of synaptophysin. Tissue biopsy with thorough immunohistochemistry is required to differentiate precursor T-ALL/T-LBL from thymoma and small cell carcinoma.     

Age-related Epstein-Barr virus-positive cutaneous ulcer arising after a self-limited subcutaneous abscess: a case report

ABSTRACT: INTRODUCTION: Epstein-Barr virus-positive mucocutaneous ulcer is a newly recognized clinicopathologic entity in the spectrum of Epstein-Barr virus-positive lymphoproliferative disorders. This entity is characterized by a self-limited, indolent course. CASE PRESENTATION: We report the case of a 74-year-old, type 2 diabetic man who presented with an ulceroinfiltrative skin lesion on the left side of his neck. Histological examination showed that the lesion consisted of large atypical cells, some with Hodgkin-Reed-Sternberg-like morphology, in the midst of reactive lymphocytes, plasma cells, eosinophils and histiocytes. The atypical cells were partially positive for CD45, CD20, CD79a, CD30, B-cell lymphoma 2 and latent membrane protein 1 (CS.1-4), and negative for CD15, B-cell lymphoma 6 and CD10. In situ hybridization for Epstein-Barr virus-encoded ribonucleic acid was positive. Two years before, the patient had been diagnosed with a self-limited subcutaneous abscess in the same anatomic area that healed after antibiotic therapy. CONCLUSION: Older patients with positive Epstein-Barr virus serology may develop B-cell lymphoproliferations due to age-related immune suppression. Epstein-Barr virus-encoded ribonucleic acid testing and clonality analysis, eventually complemented with close clinical follow-up, should be performed for suspicious inflammatory lesions in older patients.     

儿童皮肤肥大细胞瘤的临床病理分析

目的探讨儿童皮肤肥大细胞瘤的临床病理特征。方法对5例皮肤肥大细胞瘤进行临床病理观察和免疫组化检测。结果患者年龄3个月-8岁,3例出生时即有病变,1例在出生后半年内,另一例在7岁时发现病变,均无明显症状,免疫组化示CD43、CD117、LCA、VIM阳性,甲苯胺蓝染色见胞浆内有紫红色颗粒。结论皮肤肥大细胞瘤好发于儿童,大多数在出生时即有或6个月内发病,临床医生易诊断为脉管瘤。组织病理学上关键在于认识肥大细胞,结合免疫组化和甲苯胺蓝染色,并通过询问病史可以确诊。儿童皮肤肥大细胞瘤预后良好,在青春期会自动消退。     

CD8 cells of patients with diffuse cutaneous leishmaniasis display functional exhaustion: the latter is reversed, in vitro, by TLR2 agonists

Leishmania mexicana (Lm) causes localized (LCL) and diffuse (DCL) cutaneous leishmaniasis. DCL patients have a poor cellular immune response leading to chronicity. It has been proposed that CD8 T lymphocytes (CD8) play a crucial role in infection clearance, although the role of CD8 cytotoxicity in disease control has not been elucidated. Lesions of DCL patients have been shown to harbor low numbers of CD8, as compared to patients with LCL, and leishmanicidal treatment restores CD8 numbers. The marked response of CD8 towards Leishmania parasites led us to analyze possible functional differences between CD8 from patients with LCL and DCL. We compared IFNγ production, antigen-specific proliferation, and cytotoxicity of CD8 purified from PBMC against autologous macrophages (MO) infected with Leishmania mexicana (MOi). Additionally, we analyzed tissue biopsies from both groups of patients for evidence of cytotoxicity associated with apoptotic cells in the lesions. We found that CD8 cell of DCL patients exhibited low cytotoxicity, low antigen-specific proliferation and low IFNγ production when stimulated with MOi, as compared to LCL patients. Additionally, DCL patients had significantly less TUNEL+ cells in their lesions. These characteristics are similar to cellular "exhaustion" described in chronic infections. We intended to restore the functional capacity of CD8 cells of DCL patients by preincubating them with TLR2 agonists: Lm lipophosphoglycan (LPG) or Pam3Cys. Cytotoxicity against MOi, antigen-specific proliferation and IFNγ production were restored with both stimuli, whereas PD-1 (a molecule associated with cellular exhaustion) expression, was reduced. Our work suggests that CD8 response is associated with control of Lm infection in LCL patients and that chronic infection in DCL patients leads to a state of CD8 functional exhaustion, which could facilitate disease spread. This is the first report that shows the presence of functionally exhausted CD8 T lymphocytes in DCL patients and, additionally, that pre-stimulation with TLR2 ligands can restore the effector mechanisms of CD8 T lymphocytes from DCL patients against Leishmania mexicana-infected macrophages.     

Down-regulation of macrophage CD9 expression by interferon-gamma.

CD9, a member of the tetraspanin family is a cell surface marker expressed on myeloid and nonmyeloid as well as on neoplastic cells. The present study has focused on the role of inflammation and macrophage activation in the regulation of CD9 expression. We report that the expression of CD9 on primary cultures of murine peritoneal macrophages was down regulated by Interferon-gamma, IFN-gamma. This down regulation was concentration-dependent and maximal by 48 h. The changes in surface expression were consistent with similar reductions in CD9 protein and message levels by Western and Northern blot analyses. The mechanism by which IFN-gamma decreases CD9 expression appears to be through the Stat1 signaling pathway as Stat1 knockout mice did not demonstrate any reduction in CD9 expression by IFN-gamma treatment. These results represent the first evidence for the down regulation of CD9 expression with macrophage activation.