Mojmír Moulis

Rapid Detection and Identification of Mucormycetes from Culture and Tissue Samples by Use of High-Resolution Melt Analysis

ABSTRACT We present a method for rapid and simple detection of clinically relevant mucormycetes of the Mucorales order in cultures and clinical samples. This seminested real-time PCR uses mucormycete-specific primers and is followed by species identification using high-resolution melt (HRM) analysis. The method is highly suitable for routine clinical diagnostics.

Rapid Detection and Identification of Mucormycetes in Bronchoalveolar Lavage Samples from Immunocompromised Patients with Pulmonary Infiltrates by Use of High-Resolution Melt Analysis

ABSTRACT Rapid differential diagnostics of pulmonary infiltrates suspected of invasive fungal disease in an immunocompromised host and early initiation of effective antifungal therapy are crucial for patient outcomes. There are no serological tests available to detect mucormycetes; therefore, PCR-based methods are highly suitable. We validated our previously published PCR followed by high-resolution melt analysis (PCR/HRMA) to detect Rhizopus spp., Rhizomucor pusillus, Lichtheimia corymbifera, and Mucor spp. in bronchoalveolar lavage (BAL) samples from immunocompromised patients who were at risk of invasive fungal disease. All PCR/HRMA-positive samples were retested using novel real-time quantitative PCR (RQ PCR) assays specific to the species identified. In total, between January 2009 and December 2012 we analyzed 99 BAL samples from 86 patients with pulmonary abnormalities using PCR/HRMA. Ninety (91%) BAL samples were negative, and 9 (9%) samples were positive. The sensitivity and specificity of PCR/HRMA were 100% and 93%, respectively. By combining the positive results of PCR/HRMA with positive RQ PCR results, the specificity was raised to 98%. PCR/HRMA, due to its high negative predictive value (99%), represents a fast and reliable tool for routine BAL sample screening for the differential diagnosis of pulmonary infiltrates in immunocompromised patients for the four most clinically important mucormycetes.

Retrospective analysis of 235 unselected patients with mantle cell lymphoma confirms prognostic relevance of Mantle Cell Lymphoma International Prognostic Index and Ki-67 in the era of rituximab: long-term data from the Czech Lymphoma Project Database

Abstract Although a prognostic model (MIPI, Mantle Cell Lymphoma International Prognostic Index) for patients with mantle cell lymphoma (MCL) has been established, its clinical significance for daily practice in the rituximab era remains controversial. Data of 235 unselected patients with MCL from the Czech Lymphoma Project Database were analyzed. MIPI, simplified MIPI (s-MIPI) and Ki-67 proliferation index were assessed for all patients and for a subgroup of 155 rituximab-treated (RT) patients. MIPI divided all patients into subgroups of low-risk (22%), intermediate-risk (29%) and high-risk (49%), with median overall survival 105.8 vs. 54.1 vs. 24.6 months, respectively (p < 0.001). s-MIPI revealed similar results. The validity of both indexes was confirmed in RT patients. We confirmed the Ki-67 index to be a powerful single prognostic factor for overall survival (64.4 vs. 20.1 months, p < 0.001) for all patients and for the RT subset. Our results confirm the clinical relevance of MIPI, s-MIPI and Ki-67 for risk stratification in MCL also in the rituximab era.

Clinical relevance of uPA, uPAR, PAI 1 and PAI 2 tissue expression and plasma PAI 1 level in colorectal carcinoma patients.

BACKGROUND/AIMS Urokinase (uPA) is a serine protease, which together with uPAR, tPA, PAI 1 and PAI 2 forms the plasminogen activator system, a component of metastatic cascade contributing to the invasive growth and angiogenesis of malignant tumours. METHODOLOGY Both preceding therapy and after 6-8 weeks of the treatment, plasma PAI 1 levels (photometric microplate method on the ELISA) and uPA, uPAR, PAI 1 and PAI 2 tissue expression (immunohistochemical reaction) were analysed from 80 colorectal carcinoma patients. RESULTS Analysis showed higher pre-treatment plasma levels of PAI 1 in patients with advanced tumours, which decreased after surgery or the start of therapy (p=0.004); Patients with higher plasma level PAI 1 before (0.013) and after therapy (0.004) had significantly shorter survival. There was a higher expression of uPA (p<0.001), uPAR (p<0.001), PAI 1 (p=0.042) and PAI 2 (p<0.001) in advanced colorectal carcinoma. A relationship between PAI 2 (p=0.010) and uPAR (p=0.019) expression and survival was demonstrated. There is a correlation between pre-treatment plasma PAI 1 levels and PAI 2 (p=0.028) and uPAR (p=0.043) expression. CONCLUSIONS Immunohistochemical analysis of PAS in tumour tissue and plasma PAI 1 levels was found to be a useful prognostic factor in colorectal carcinoma patients. Plasma PAI 1 could be advantageous in evaluating the effectiveness of a mode of treatment.

Complex analysis of cyclin D1 expression in mantle cell lymphoma: two cyclin D1-negative cases detected

Background and Aim: The cytogenetic and diagnostic hallmark of mantle cell lymphoma (MCL) is translocation t(11;14)(q13;q32), resulting in overexpression of cyclin D1. Cyclin D1 expression was analysed in 32 cases of MCL. Methods: The t(11;14) translocation was detected by fluorescence in situ hybridisation, level of cyclin D1 mRNA by competitive RT-PCR, and level of cyclin D1 and D2 proteins by immunohistochemistry and/or immunoblotting. Results: In 30 cases, the presence of translocation t(11;14), a high level of cyclin D1 mRNA, and a high level of the cyclin D1 protein were confirmed. Two cyclin D1-negative cases overexpressing cyclin D2 were detected by immunoblotting. Conclusions: There are rare cyclin D1-negative cases of MCL overexpressing cyclin D2. Anti-cyclin D1 antibodies with low specificity can bind both cyclin D1 and cyclin D2, thus providing false cyclin D1-positive signals in immunohistochemical analysis.

Cladribine (2-chlorodeoxyadenosine) in frontline chemotherapy for adult Langerhans cell histiocytosis: A single-center study of seven cases

Abstract Background. Adult Langerhans cell histiocytosis is a rare disorder with diverse clinical manifestations and inconsistent treatment outcomes to conventional therapeutic regimens. Cladribine (2-chlorodeoxyadenosine) repeatedly proved effective in cases of relapsed multifocal and multisystem disease forms. In this retrospective study we present an analysis of cladribine in frontline systemic therapy. Material and methods. A cohort of seven male patients with biopsy proved multisystem (six cases) and multifocal (one case) Langerhans cell histiocytosis received cladribine at a dose of 5 mg/m2 subcutaneously (five cases) or by two-hour intravenous infusion (two cases) over five consecutive days, every four weeks for a median of four courses (range 4–6). The treatment was enhanced with cyclophosphamide (300 mg intravenously on days 1–5 in cycles 4–6) and corticoids (dexamethasone 24 mg orally or methylprednisolone 250 mg intravenously on days 1–5 in cycles 4–6) in two patients, with radiotherapy (20 Gy on skin or bone lesions) in three patients and with photochemotherapy (psoralen plus ultraviolet A light, PUVA) on skin lesions in one patient. Results. All patients achieved clinically relevant treatment response confirmed by positron emission tomography (PET). Durable complete remissions were maintained in six patients (86%), including two patients with hypophysis involvement, with the median follow-up of 37 months (range 15–94; 49.8 ± 35.2 [6]). One patient had an aggressive, early relapsing disease requiring further treatment lines. The treatment-related toxicities consisted of transient bone marrow suppression affecting the leukocytes predominantly. Grade 3 lymphopenia occurred in five patients (71%) and grade 3 neutropenia in one patient (14%). Conclusion. Cladribine, both as a single agent as well as in combination with an alkylating cytostatic and corticoids, represents an effective treatment option with favorable toxicity profile for adult patients with multisystem or aggressive multifocal form of Langerhans cell histiocytosis.

Virtual microscope interface to high resolution histological images

The Hypertext atlas of Dermatopathology, the Atlas of Fetal and Neonatal Pathology and Hypertext atlas of Pathology (this one in Czech only) are available at http://www.muni.cz/atlases. These atlases offer many clinical, macroscopic and microscopic images, together with short introductory texts. Most of the images are annotated and arrows pointing to the important parts of the image can be activated.The Virtual Microscope interface is used for the access to the histological images obtained in high resolution using automated microscope and image stitching, possibly in more focusing planes. Parts of the image prepared in advance are downloaded on demand to save the memory of the users computer. The virtual microscope is programmed in JavaScript only, works in Firefox/Mozilla and MSIE browsers without need to install any additional software.

Complex analysis of the TP53 tumor suppressor in mantle cell and diffuse large B-cell lymphomas

Mutations and deletions of the tumor suppressor TP53 gene are the most frequent genetic alterations detected in human tumors, though they are rather less frequent in lymphomas. However, acquisition of the TP53 mutation was demonstrated to be one of the characteristic markers in mantle cell lymphoma (MCL) and diffuse large B-cell lymphoma (DLBCL) and prognostic value of the TP53 status has been recognized for these diseases. We present the complex analysis of the TP53 aberrations in 57 cases of MCL and 131 cases of DLBCL. The TP53 status was determined by functional analyses in yeast (FASAY) followed by cDNA and gDNA sequencing. The level of the p53 protein was assessed by immunoblotting and loss of the TP53-specific locus 17p13.3 was detected by FISH. Altogether, we detected 13 TP53 mutations among MCL cases (22.8%) and 29 TP53 mutations in 26 from 131 DLBCL cases (19.8%). The ratio of missense TP53 mutations was 76.9% in MCL and 82.8% in DLBCL. The frequency of TP53 locus deletion was rather low in both diseases, reaching 9.3% in MCL and 15.3% in DLBCL. The presence of TP53 mutation was associated with shorter overall survival (OS) and progression-free survival (PFS) in MCL. Among DLBCL cases, the TP53 mutations shortened both OS and PFS of patients treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) and decreased both OS and PFS of patients with secondary DLBCL disease.

Salvage lenalidomide in four rare oncological diseases

In rare disorders, there are often no standard therapy recommendations. Patients with refractory disease may require novel experimental approaches. Applied as second- up to fourth-line treatment, lenalidomide (10-25 mg perorally on days 1-21 in a 28-day cycle) was used in our cohort of four adult patients with aggressive, multisystem and relapsing diseases. Complete and long-lasting remissions (more than 1 year, no maintenance therapy) were achieved in patients with Langerhans cell histiocytosis (11 cycles, combination with dexamethasone and etoposide, consolidated by allogeneic blood stem cell transplant) and plasma-cell Castleman disease (15 cycles, monotherapy). Mixed response with complete disappearance of brain infiltrates was reached in Erdheim-Chester disease (6 cycles, monotherapy) and gastrointestinal bleeding was well controlled in multiple angiomatosis (9 cycles, combination with thalidomide). For disease activity evaluation each patient underwent fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography scan imaging, which was complemented by clinical and laboratory investigations.

NOD/SCID IL2Rγ-null mouse xenograft model of human p53-mutated chronic lymphocytic leukemia and ATM-mutated mantle cell lymphoma using permanent cell lines.

Xenograft models represent a promising tool to study the pathogenesis of hematological malignancies. To establish a reliable and appropriate in vivo model of aggressive human B-cell leukemia and lymphoma we xenotransplanted four p53-mutated cell lines and one ATM-mutated cell line into immunodeficient NOD/SCID IL2Rγ-null mice. The cell lines MEC-1, SU-DHL-4, JEKO-1, REC-1, and GRANTA-519 were transplanted intraperitoneally or subcutaneously and the engraftment was investigated using immunohistochemistry and flow cytometry. We found significant differences in engraftment efficiency. MEC-1, JEKO-1 and GRANTA-519 cell lines engrafted most efficiently, while SU-DHL-4 cells did not engraft at all. MEC-1 and GRANTA-519 massively infiltrated organs and the whole intraperitoneal cavity showing very aggressive growth. In addition, GRANTA-519 cells massively migrated to the bone marrow regardless of the transplantation route. The MEC-1 and GRANTA-519 cells can be especially recommended for in vivo study of p53-mutated chronic lymphocytic leukemia and ATM-mutated mantle cell lymphoma, respectively.