Value of GCET1, HGAL (GCET2), and LMO2 in the Determination of Germinal Center Phenotype in Diffuse Large B-cell Lymphoma

Objective

Diffuse large B-cell lymphoma (DLBCL) is a biologically heterogeneous disease that is classified into germinal center B-cell (GCB) and non-GCB subtypes, which are prognostically different. The Hans algorithm is the most widely used tool based on CD10, BCL6, and MUM1 expression, but some cases with the non-GCB phenotype are still known to be misclassified. In this study, we investigate the extent to which GCET1, HGAL, and LMO2 protein expressions reflect GCB phenotype together with their roles in determining the GCB phenotype of DLBCL and their contributions to the performance of the Hans algorithm.

Materials and Methods

Sixty-five cases of DLBCL-not otherwise specified, 40 cases of follicular lymphoma (FL), and 19 non-GC-derived lymphoma cases were included in this study. The DLBCL cases were grouped as CD10+ (Group A) or only MUM1+ (Group B), and the remaining cases constituted the intermediate group (Group C). GCET1, HGAL, and LMO2 expressions were evaluated.

Results

In the FL group, GCET1, HGAL, and LMO2 were positive in 85%, 77.5%, and 100% of the cases, respectively. Among the non-GC-derived lymphoma cases, all three markers were negative in cases of small lymphocytic lymphoma, plasmablastic lymphoma, peripheral T-cell lymphoma, and anaplastic large cell lymphoma. GCET1 and HGAL were negative in cases of marginal zone lymphoma (MZL) and mantle cell lymphoma (MCL). Two of the 3 MZL and 2 of the 4 MCL cases were positive for LMO2. In the DLBCL group, the number of cases with GCET1, HGAL, and LMO2 positivity was 18 (90%), 17 (85%), and 20 (100%), respectively, in Group A and 0 (0%), 2 (13.3%), and 2 (13.3%), respectively, in Group B. Considering these rates, when the cases in the intermediate group were evaluated, it was concluded that 13 cases typed as non-GCB according to the Hans algorithm may have the GCB phenotype.

Conclusion

GCET1, HGAL, and LMO2 are highly sensitive markers for determining the germinal center cell phenotype and can increase the accuracy of the subclassification of DLBCL cases, especially for cases that are negative for CD10.

Treatment results of modified BFM protocol in pediatric high-risk Burkitt lymphoma

BACKGROUND

Chemotherapy with high dose methotrexate is the mainstay of treatment for Burkitt lymphoma (BL), especially to manage central nervous system (CNS) disease. However, methotrexate administration requires close drug level monitoring for appropriate folinic acid rescue, which might not be readily available in all centers. In this study, we assessed the long-term treatment outcomes of a modified Non-Hodgkin lymphoma (NHL)-Berlin-Frankfurt-Munster (BFM) 90 regimen in pediatric high-risk BL without CNS involvement.

METHODS

Between 1999 and 2011, 42 patients (median age: 7 years) with advanced-stage BL were treated with modified NHL-BFM 90 regimen (methotrexate at a dose of 1 g/m2). Demographic data, stage, lactate dehydrogenase (LDH) and treatment results were retrospectively evaluated. The patients were assessed for toxicity, survival and CNS recurrence.

RESULTS

Thirty-six patients had Stage III and six had Stage IV disease, respectively. The median LDH level was 1,432 IU/L. Four patients died of infectious and metabolic complications. One patient had local recurrence at the 48 < sup > th < /sup > month of the follow-up and he is in the second remission for 72 months. In Kaplan-Meier analysis, the overall survival and event-free survival rates at 10 years were found as 90 % and 88 %, respectively. None of our patients died of treatment failure.

CONCLUSIONS

The administration of the reduced dose of methotrexate seems to not compromise treatment success nor increase the risk of CNS recurrence in high-risk BL without CNS involvement. The limitation of the study is that it is not randomized. Our treatment scheme might be considered for centers without methotrexate measurement facility.

Invasive Saprochaete capitata Infection in a Patient with Autosomal Recessive CARD9 Deficiency and a Review of the Literature

PURPOSE

Autosomal recessive (AR) CARD9 deficiency is an inherited immune disorder which results in impaired innate immunity against various fungi. Superficial and invasive fungal infections, mainly caused by Candida or Trichophyton species, are the hallmark of CARD9 deficiency. Together with the increasing number of CARD9-deficient patients reported, different pathogenic fungal species have been described such as Phialophora, Exophiala, Corynespora, Aureobasidium, and Ochroconis. Saprochaete capitata is an opportunistic infectious agent in immunocompromised patients and is a common cause of invasive fungal disease in patients with hematological malignancies. In this study, we investigated the causative genetic defect in a patient with S. capitata fungal infection which disseminated to lymph nodes and common bile duct.

METHODS

The identification of the isolated yeast strain was made by direct microscopic examination and confirmed by internal transcribed spacer (ITS) sequencing. We applied whole exome sequencing to search for the disease-causing mutation. Sanger sequencing was used to validate the mutation in the patient and his parents.

RESULTS

S. capitata was isolated from the biopsy specimen as the causative microorganism responsible for the invasive fungal disease in the patient. Whole exome sequencing revealed a homozygous c.883C > T, (p.Q295*) mutation in CARD9, confirmed by Sanger sequencing.

CONCLUSIONS

This is the first report of invasive Saprochaete infection associated with autosomal recessive (AR) CARD9 deficiency in the literature and thereby further extends the spectrum of fungal diseases seen in these patients.

The Role of the Local Bone Marrow Renin-Angiotensin System in Multiple Myeloma

Objective:

Angiotensin II promotes growth and angiogenesis via type 1 receptors (AGTR1) in certain tumors. In this study, we examine the bone marrow AGTR1 expression in multiple myeloma (MM) and its relationship with the regulation of angiogenesis and prognostic factors.

Materials and Methods:

Bone marrow AGTR1 mRNA levels of 39 MM patients and 15 healthy controls were analyzed with quantitative RT-PCR. Immunohistochemical staining of the tissue vascular endothelial growth factor (VEGF), CD34, and factor VIIIrAg (fVIIIrAg) was used to assess bone marrow angiogenesis.

Results:

Bone marrow samples of the patients showed increased VEGF, fVIIIrAg, and CD34 staining and higher AGTR1 expression levels when compared to controls. Patients with severe-diffuse bone marrow infiltration showed higher bone marrow VEGF, fVIIIrAg, CD34, and AGTR1 mRNA levels when compared to other patients.

Conclusion:

AGTR1 expression was found positively correlated with plasma β2-microglobulin level and patients with increased AGTR1 expression showed increased bone marrow CD34 levels.

Increased costimulatory molecule expression of thymic and peripheral B cells and a sensitivity to IL-21 in myasthenia gravis

B cells may contribute to the pathogenesis of myasthenia gravis with anti-acetylcholine antibodies (AChR+ MG) by co-stimulation or selection of T cells. In this study, we investigated costimulatory molecules on B cells in the blood and in the thymus as well as by TLR9 and IL-21 stimulations in AChR+ MG patients with or without immunosuppressive treatment and controls. CD80 and CD86 expression on B cells was increased in the peripheral blood and in the thymus of untreated patients. CD86 was further amplified by IL-21. A role for activated B cells, active thymic environment and IL-21 is implicated in MG.

DEK protein level is a biomarker of CD138positive normal and malignant plasma cells

Overexpression of DEK oncogene is associated with increased proliferation of carcinoma cells and it is observed in several solid tumors due to the amplification of the 6p22.3 chromosomal region where DEK locates. Although the same chromosomal amplification occurs in multiple myeloma (MM), a plasma cell neoplasm, whether the expression and the copy number of the DEK gene are affected in MM remains elusive. We show that despite the increased copy number in CD138positive MM cells (4 out of 41 MM samples), DEK mRNA expression was down-regulated compared with that in CD138negative bone marrow (BM) cells of the same patients (P<0.0001). DEK protein was not detectable by immunohistochemistry (IHC) in CD138positive normal plasma cells or in malignant plasma cells of MM patients (n = 56) whereas it was widely expressed in normal and neoplastic B-cells. Stable knockdown or overexpression of DEK in CD138positive MM cell lines did not affect the proliferation and viability of the cells profoundly in the presence or absence of chemotherapeutic agent melphalan whereas knockdown of DEK moderately but significantly increased the expression level of CD138 (p<0.01). Decreased DEK expression in plasma cells suggests a potential role of this gene in plasma cell development and lack of detectable DEK protein by IHC could be used as a biomarker for normal and malignant plasma cells.

[Microvascular obstruction due to thrombosis and fibrin deposition in myocardial infarction]

OBJECTIVE

It is widely known that myocardial damage is not immediately terminated after the elimination of epicardial occlusion in cases of myocardial infarction. In situ thrombosis during epicardial occlusion might contribute to poor myocardial perfusion after reperfusion of an occluded epicardial artery. In the current study, we sought to determine the effects of ischemia and reperfusion on microvascular thrombotic occlusion.

METHODS

Thirty male Wistar rats were included in the study. After the rats had been anesthetized and thoracotomized, the left coronary artery was occluded for 30 minutes in the first group, and it was occluded for 30 minutes and reperfused for an additional 20 minutes in the second group. Ten rats were used as a sham-operated control group. After completion of the study protocol, excised heart preparations were analyzed by immunohistochemistry and electron microscopy.

RESULTS

A significant difference was found between the infarction plus reperfusion group and the other 2 groups, with respect to microvascular fibrin and thrombocyte deposition in immunohistochemistry analysis. These results were confirmed by morphological examination with electron microscopy.

CONCLUSION

In situ fibrin formation accompanies microvascular obstruction in acute myocardial infarction. Our results indicate that additional therapeutic approaches are needed in order to achieve better tissue perfusion in contemporary treatment of acute myocardial infarction after successful reopening of the infarct-related artery.

Osteoporosis and osteopathy markers in patients with mastocytosis

Objective:

Osteoporosis, osteosclerosis, and lytic bone lesions have been observed in patients with systemic mastocytosis (SM). We examined bone mineral density (BMD) biochemical turnover markers and serum tryptase levels in SM, which is considered a rare disease.

Materials and Methods:

Seventeen adult patients (5 females, 12 males; median age: 33 years, range: 20-64) with mastocytosis were included in this study. We investigated the value of quantitative ultrasound (QUS) of the calcaneus in the assessment of BMD in SM patients, as well as BMD of the lumbar spine (L1-L4), femoral neck, and distal radius using dual energy x-ray absorptiometry (DXA) and plasma tryptase levels, biochemical markers of bone turnover.

Results:

At lumbar spine L1-L4, the femoral neck, and the distal radius or as calcaneus stiffness, 12 of 17 patients had T-scores of less than -1 at least at 1 site, reflecting osteopenia. Three of 17 patients had T-scores showing osteoporosis (T-score <-2.5). There was no relationship between DXA and bone lesion severity. We also found a significant positive correlation between tryptase levels and disease severity, as well as between disease severity and pyridinoline (p<0.01 by Spearman’s test).

Conclusion:

DXA and calcaneal QUS may not be appropriate techniques to assess bone involvement in SM patients because of the effects of osteosclerosis. This study further shows that the osteoclastic marker pyridinoline is helpful in patients with severe disease activity and sclerotic bone lesions to show bone demineralization.

Isolated central nervous system relapse in a child with non- Hodgkin lymphoma during treatment

Isolated central nervous system (CNS) relapse of non-Hodgkin lymphoma (NHL) is very rare. We report a five-year-old boy with T-cell lymphoblastic lymphoma (T-LBL), who developed CNS relapse under treatment when the primary tumor was in complete remission. The patient presented initially with persistent cough and an anterior mediastinal mass and had no bone marrow or CNS involvement at diagnosis. During re-induction treatment, a routine lumbar puncture revealed blasts in the cerebrospinal fluid (CSF). The patient developed neurological signs and symptoms consequently. Craniospinal radiotherapy followed by BFM (Berlin-Frankfurt-Münster) high-risk chemotherapy protocol was initiated. Despite complete response after three courses, the patient experienced CNS relapse and expired due to disease progression. In the treatment of a NHL patient, routine CSF analysis should be done for tumor cells even when the primary disease is in complete remission.

Use of laboratory-grown bacterial alginate in copper removal

Industrial production leads to toxic heavy metal pollution in water bodies. Copper is one of the examples that requires removal from effluents before being discharged. It is difficult and sometimes very expensive to remove toxic heavy metals by conventional treatment techniques. This study aims to remove copper by the use of bacterial alginate as a non-conventional technique. Bacterial alginates (natural polymers composed of mannuronic and guluronic acid monomers) were synthesized by Azotobacter vinelandii ATCC(®) 9046 in a laboratory fermentor under controlled environmental conditions. The alginates produced, with a range of different characteristics in terms of monomer distribution and viscosity, were investigated for maximum copper uptake capacities. The average copper uptake capacities of alginates produced were found to be about 1.90 mmol/L Cu(2+)/g alginate. Although the GG-block amount of alginates was varied from 12 to 87% and culture broth viscosities were changed within the range of 1.47 and 14 cP, neither the block distribution nor viscosities of alginate samples considerably affected the copper uptake of alginates.

Intestinal Langerhans cell histiocytosis-like lesion in an adult presented with diverticulitis: a reactive or neoplastic condition?

The involvement of the gut by Langerhans cell histiocytosis (LCH) is very rare in adults; however this is usually observed with a disseminated disease in children. We report a 75-year-old male patient who underwent right hemicolectomy for a complicated intestinal diverticular disease. The surgical specimen revealed LCH-like proliferative lesion associated with diverticulitis. The overall morphological and immunohistochemical findings are indistinguishable from LCH. Systemic scans and subsequently performed bone marrow biopsies were free of disease. Although the HUMARA clonality assay cannot be assessed, the lack of evidence of LCH progression or disease elsewhere in the whole body strongly supported the possibility of an atypical reactive phenomenon probably due to the underlying intestinal diverticular disease. Therefore, it is important to avoid diagnosing such a unifocal Langerhans cell proliferation as LCH in patients with underlying pathologies in the absence of systemic involvement. Therefore, without knowledge of clonal status of a unifocal Langerhans cell proliferation, we recommend using the terminology of LCH-like lesion.

The Outcome of Large B-Cell Lymphoma Evolving in a Hematopoietic Stem Cell Transplant Patient During Treatment of Chronic Graft-Versus-Host Disease

Immunosuppression is a risk factor for the development of posttransplant lymphoproliferative disorder. This type of malignancy developed in an immunocompromised man. The patient presented with focal convulsion starting from right face and right arm followed by two generalized convulsions with one minute interval. Diagnosis was made by computed tomographic (CT) scan of the cranium following oral and intravenous administration of contrast dyes which revealedmass leisons in the frontotemporal lobe and by stereotaxic biopsy. Tissue sections showed a malignant tumor cell infiltration with large areas of necrosis and many mitoses. Many tumor cells were positive for CD 20 and CD 10. These findings were consistent with large B-cell lymphoma. Central nervous system radiation with a dose of 56 Gy was given with clinical and radiological improvement. The patient died due to multiorgan failure. Finally, the immunocompromised patients should be closely followed for the development of lymphoproliferative disorder.