Endoglin (CD 105) is expressed on endothelial cells in the primary central nervous system lymphomas and correlates with survival

Elevated expression of N-myc downstream regulated gene 1 protein in glioblastomas reflects tumor angiogenesis and poor patient prognosis

N-myc downstream regulated gene 1 (NDRG1) is a member of the NDRG family, of which four members (NDRG1, NDRG2, NDRG3, and NDRG4) have been identified. NDRG1 is repressed by c-MYC and N-MYC proto-oncogenes. NDRG1 is translated into a 43 kDa protein that is associated with the regulation of cellular stress responses, proliferation, and differentiation. In this study, we aimed to clarify the relationship between progression of glioblastoma (GB) IDH-wildtype and NDRG1 expression in tumor cells. We assessed the expression of NDRG1 in 41 GBs using immunostaining and evaluated its prognostic significance. NDRG1 expression by GBs was evaluated using Histoscore, which showed high and low scores in 23 and 18 cases, respectively. NDRG1-positive cells were strongly expressed in Ki-67 labeled proliferating tumor cells and CD105 positive proliferating microvessels around the area of palisading necrosis. Statistical analyses showed lower survival rates in the high-score group than the low-score group (P < 0.01). This study indicated that overexpression of NDRG1 by GB reflects tumor angiogenesis and poor patient prognosis.

Correlation of functional magnetic resonance imaging features of primary central nervous system lymphoma with vasculogenic mimicry and reticular fibers

Objective

To deepen the imaging-pathological mechanism of primary central nervous system lymphoma (PCNSL) and provide a theoretical basis for clinical diagnosis and treatment, the functional magnetic resonance imaging (fMRI) characteristics of PCNSL were analyzed, and the relationship between the fMRI characteristics and vasculogenic mimicry (VM) and reticular fiber in PCNSL was discussed.

Methods

Ninety-six patients with PCNSL treated in our hospital were divided into three groups according to the pathological examination results, including strong positive group of VM (n = 40), weak positive group of VM (n = 56), strong positive group of reticular fiber (n = 45) and weak positive group of reticular fiber (n = 51). The levels of augmentation index and apparent diffusion coefficient (ADC) were compared among the groups. receiver operator characteristic (ROC) curve analysis was used to analyze the clinical value of ADC value in differential diagnosis of PCNSL.

Results

The levels of augmentation index in the strong positive group of VM were significantly higher than that in the weak positive group of VM, and the ADC value in the strong positive group of VM was significantly lower than that in the weak positive group of VM (P < 0.001). The levels of augmentation index in the strong positive group of reticular fiber were significantly higher than that in the weak positive group of reticular fiber, and ADC value in the strong positive group of reticular fiber was significantly lower than that in reticular fiber weak positive group (P < 0.001). Pearson correlation analysis showed that the levels of augmentation index were positively correlated with VM and reticular fiber (r = 0.529, 0.548, P < 0.001) and the ADC value was negatively correlated with VM and reticular fiber (r = -0.485, -0.513, P < 0.001). There was a significant negative correlation between necrotic lesions and VM (r = -0.185, P < 0.05). The area under the curve (AUC) values of average ADC value, minimum ADC value, and maximum ADC value for individual differential diagnosis of PCNSL were 0.920, 0.901, and 0.702, while the AUC of the combined differential diagnosis was 0.985, with a sensitivity of 95.00 % and a specificity of 92.70 %.

Conclusion

The levels of augmentation index and the ADC value of PCNSL focus are significantly correlated with VM and reticular fiber, and there is a strong negative correlation between necrotic lesions and VM. MRI imaging technology is of great significance in revealing the biological behavior of PCNSL, which can effectively reveal the relationship between VM and reticular fibers and the MRI characteristics in PCNSL, thereby providing a new imaging basis for the clinical diagnosis and treatment of PCNSL.

Targeting the tumor microenvironment in primary central nervous system lymphoma: Implications for prognosis

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma, and there is limited research on its tumor microenvironment (TME). Nevertheless, more and more studies have evidence that TME has essential effects on tumor cell proliferation, immune escape, and drug resistance. Thus, it is critical to elucidate the role of TME in PCNSL. The understanding of the PCNSL TME is gradually unfolding, including factors that distinguish it from systemic diffuse large B-cell lymphoma (DLBCL). The TME in PCNSL exhibits both transcriptional and spatial intratumor heterogeneity. Cellular interactions between tumor cells and stroma cells reveal immune evasion signaling. The comparative analysis between PCNSL and DLBCL suggests that PCNSL is more likely to be an immunologically deficient tumor. In PCNSL, T cell exhaustion and downregulation of macrophage immune function are accompanied by suppressive microenvironmental factors such as M2 polarized macrophages, endothelin B receptor, HLA depletion, PD-L1, and TIM-3. MMP-9, Integrin-β1, and ICAM-1/LFA-1 play crucial roles in transendothelial migration towards the CNS, while CXCL13/CXCR5, CD44, MAG, and IL-8 are essential for brain parenchymal invasion. Further, macrophages, YKL-40, CD31, CD105, PD-1/PD-L1 axis, osteopontin, galectin-3, aggregative perivascular tumor cells, and HLA deletion may contribute to poor outcomes in patients with PCNSL. This article reviews the effect of various components of TME on the progression and prognosis of PCNSL patients to identify novel therapeutic targets.

Extranodal lymphoma: pathogenesis, diagnosis and treatment

Approximately 30% of lymphomas occur outside the lymph nodes, spleen, or bone marrow, and the incidence of extranodal lymphoma has been rising in the past decade. While traditional chemotherapy and radiation therapy can improve survival outcomes for certain patients, the prognosis for extranodal lymphoma patients remains unsatisfactory. Extranodal lymphomas in different anatomical sites often have distinct cellular origins, pathogenic mechanisms, and clinical manifestations, significantly influencing their diagnosis and treatment. Therefore, it is necessary to provide a comprehensive summary of the pathogenesis, diagnosis, and treatment progress of extranodal lymphoma overall and specifically for different anatomical sites. This review summarizes the current progress in the common key signaling pathways in the development of extranodal lymphomas and intervention therapy. Furthermore, it provides insights into the pathogenesis, diagnosis, and treatment strategies of common extranodal lymphomas, including gastric mucosa-associated lymphoid tissue (MALT) lymphoma, mycosis fungoides (MF), natural killer/T-cell lymphoma (nasal type, NKTCL-NT), and primary central nervous system lymphoma (PCNSL). Additionally, as PCNSL is one of the extranodal lymphomas with the worst prognosis, this review specifically summarizes prognostic indicators and discusses the challenges and opportunities related to its clinical applications. The aim of this review is to assist clinical physicians and researchers in understanding the current status of extranodal lymphomas, enabling them to make informed clinical decisions that contribute to improving patient prognosis.

High intratumoral susceptibility signal grade on susceptibility-weighted imaging: a risk factor for hemorrhage after stereotactic biopsy

OBJECTIVE

This study aimed to examine the association of preoperative intratumoral susceptibility signal (ITSS) grade with hemorrhage after stereotactic biopsy (STB).

METHODS

The authors retrospectively reviewed 66 patients who underwent STB in their institution. Preoperative factors including age, sex, platelet count, prothrombin time-international normalized ratio, activated thromboplastin time, antiplatelet agent use, history of diabetes mellitus and hypertension, target location, anesthesia type, and ITSS data were recorded. ITSS was defined as a dot-like or fine linear low signal within a tumor on susceptibility-weighted imaging (SWI) and was graded using a 3-point scale: grade 1, no ITSS within the lesion; grade 2, 1-10 ITSSs; and grade 3, ≥ 11 ITSSs. Postoperative final tumor pathology was also reviewed. The association between preoperative variables and the size of postoperative hemorrhage was examined.

RESULTS

Thirty-four patients were men and 32 were women. The mean age was 66.6 years. The most common tumor location was the frontal lobe (27.3%, n = 18). The diagnostic yield of STB was 93.9%. The most common pathology was lymphoma (36.4%, n = 24). The ITSS was grade 1 in 37 patients (56.1%), grade 2 in 14 patients (21.2%), and grade 3 in 15 patients (22.7%). Interobserver agreement for ITSS was almost perfect (weighted kappa = 0.87; 95% CI 0.77-0.98). Age was significantly associated with ITSS (p = 0.0075). Postoperative hemorrhage occurred in 17 patients (25.8%). Maximum hemorrhage diameter (mean ± SD) was 1.78 ± 1.35 mm in grade 1 lesions, 2.98 ± 2.2 mm in grade 2 lesions, and 9.51 ± 2.11 mm in grade 3 lesions (p = 0.01). Hemorrhage > 10 mm in diameter occurred in 10 patients (15.2%), being symptomatic in 3 of them. Four of 6 patients with grade 3 ITSS glioblastomas (66.7%) had postoperative hemorrhages > 10 mm in diameter. After adjusting for age, ITSS grade was the only factor significantly associated with hemorrhage > 10 mm (p = 0.029). Compared with patients with grade 1 ITSS, the odds of postoperative hemorrhage > 10 mm in diameter were 2.57 times higher in patients with grade 2 ITSS (95% CI 0.31-21.1) and 9.73 times higher in patients with grade 3 ITSS (95% CI 1.57-60.5).

CONCLUSIONS

ITSS grade on SWI is associated with size of postoperative hemorrhage after STB.

Multiparametric MR Imaging Features of Primary CNS Lymphomas

Objective

Primary central nervous system lymphomas (PCNS) are relatively rare tumors, accounting for about 4% of all brain tumors. On neuroimaging, they are characterized by a low MR signal in T1, isointense in T2, bright uniform contrast enhancement, and diffusion restriction. The aim of this study is to note the lack of effectiveness of the MR/CT perfusion technique in complex multiparametric imaging in the differential diagnosis of primary lymphomas of the central nervous system in comparison with highly malignant gliomas and brain metastases.

Materials and Methods

This prospective study included 80 patients with CNS tumors examined/operated at the Federal Center for Neurosurgery (Tyumen, Russia) from 2018 to 2021. The patients were divided into 4 groups: group 1 consisted of 33 cases with primary CNS lymphomas (10 cases with atypical manifestations according to perfusion parameters and 23 cases of classic CNS lymphomas), group 2 with anaplastic astrocytomas—14 cases, group 3—23 cases with glioblastomas and group 4—10 cases with solitary metastatic lesions. The study was carried out on a General Electric Discovery W750 3T magnetic resonance tomograph, a Canon Aquilion One multispiral X-ray computed tomograph (Gadovist 7.5 ml, Yomeron 400 mg−50 ml). Additionally, immunohistochemical analysis was carried out with the following markers: CD3, CD20, CD34, Ki-67, VEGF.

Results

It has been established that MR/CT perfusion is not a highly sensitive method for visualizing primary CNS lymphomas, as previously thought, but at the same time, the method has a number of undeniable advantages that make it indispensable in the algorithm of a complex multiparametric diagnostic approach for this type of tumor. Nevertheless, PLCNS is characterized by an atypical manifestation, which is an exception to the rule.

Conclusions

The possibilities of neuroimaging of primary lymphomas, even with the use of improved techniques for collecting MR/CT data, are limited and do not always allow reliable differentiation from other neoplasms.

Primary central nervous system lymphomas with massive intratumoral hemorrhage: Clinical, radiological, pathological, and molecular features of six cases

Primary central nervous system lymphomas (PCNSLs) rarely exhibit intratumoral hemorrhage. The differential diagnosis of hemorrhagic neoplasms of the central nervous system (CNS) currently includes metastatic carcinomas, melanomas, choriocarcinomas, oligodendrogliomas, and glioblastomas. Here we present the clinical, radiological, pathological, and molecular genetic features of six cases of PCNSL associated with intratumoral hemorrhage. The median age of patients was 75 years, with male predominance. While conventional PCNSLs were associated with low cerebral blood volume (CBV), perfusion magnetic resonance imaging (MRI) revealed elevated CBV in three cases, consistent with vascular proliferation. All six cases were diagnosed pathologically as having diffuse large B-cell lymphoma (DLBCL) with a non-germinal center B-cell-like (non-GCB) phenotype; marked histiocytic infiltrates and abundant non-neoplastic T-cells were observed in most cases. Expression of vascular endothelial growth factor and CD105 in the lymphoma cells and the small vessels, respectively, suggested angiogenesis within the neoplasms. Neoplastic cells were immunohistochemically negative for programmed cell death ligand 1 (PD-L1), while immune cells in the microenvironment were positive for PD-L1. Mutations in the MYD88 gene (MYD88) (L265P) and the CD79B gene (CD79B) were detected in five and one case, respectively. As therapeutic modalities used for PCNSLs differ from those that target conventional hemorrhagic neoplasms, full tissue diagnoses of all hemorrhagic CNS tumors are clearly warranted.

Histomorphological and Morphometric Evaluation of Microvessel Density in Nodal Non-Hodgkin Lymphoma Using CD34 and CD105

Background  Expression of angiogenic markers determined by microvessel density (MVD) could be used as a reliable predictor of prognosis and as a potential target for antiangiogenic therapy in different categories of non-Hodgkin lymphoma (NHL).

Aims  The aim of this study was to evaluate MVD using immunohistochemical methods and computer-assisted quantitative image analysis in nodal NHL patients and compare CD34 and CD105 expression in lymph nodes of NHL patients.

Materials and Methods  The present study was conducted on 60 lymph node biopsies received in the Department of Pathology at our tertiary care center for histopathological examination. Representative paraffin-embedded tissue sections were stained with hematoxylin and eosin along with immunohistochemical stains for CD34 and CD105. MVDs were analyzed at 400× using automated image analyzer by two investigators independently.

Statistical Analysis  Data were calculated, tabulated, and statistically analyzed using SPSS (Statistical Package for Social Studies) statistical program version 18. The values entered were mean of morphometric parameters. In all tests, p -values below 0.05 were regarded as significant.

Results  MVD was determined by CD34 and CD105 antibody highly correlated with different categories of NHL. Higher MVD was observed in cases of aggressive NHL as compared with indolent NHL and the difference was statistically significantly. MVD using CD105 was correlated more strongly as compared to CD34 with different categories of NHL.

Conclusion  The present study concluded that NHL exhibits potent angiogenic activity that increased significantly with increasing aggressiveness. The study also demonstrated that CD105 is more specific than CD34 as a marker of neoangiogenesis in NHL.

Expression of the ghrelin/growth hormone secretagogue receptor axis and its functional role in promoting tumor growth in primary central nervous system lymphomas

Ghrelin and its receptor, growth hormone secretagogue receptor (GHS-R), have been found in a variety of malignant tumor tissues, suggesting a biological function of the ghrelin/GHS-R axis in tumor growth and progression. Among central nervous system tumors, primary central nervous system lymphomas (PCNSLs) are relatively rare and characterized by a rapid progression and poor prognosis. In order to clarify ghrelin expression and its functional role in promoting tumor growth and progression in PCNSLs, we undertook an immunohistochemical investigation for ghrelin and GHS-R expression in 43 patients and tested the effect of ghrelin inhibition on lymphoma cells. Furthermore, we investigated the expression of CD105, a marker for tumor angiogenesis, to explore its association with the ghrelin/GHS-R axis. The Kaplan-Meier method and Cox's proportional hazards regression model were used to determine the association of ghrelin/GHS-R expression with overall survival rate. The immunohistochemical study showed moderate/strong immunostaining of cells for ghrelin and GHS-R in 40 patients (93.0%) and 39 patients (90.7%), respectively. A ghrelin inhibitor did not affect tumor cell proliferation in vitro. Expression levels of ghrelin and GHS-R were divided into high and low groups by the rate of moderate-strong staining cells to tumor cells. The survival rate was significantly lower in patients with high GHS-R expression (P = 0.0368 by log-rank test; P = 0.0219 by Wilcoxon test). In addition, multivariate analysis of overall survival using Cox's proportional hazards regression model indicated that GHS-R was a significant independent prognostic factor (P = 0.0426). CD105 expression on tumor vessels was positive in 33 patients (33/37, 89.2%). There was a positive correlation between the moderate-strong staining rate of ghrelin and CD105-positive vessel count. These results indicated that the ghrelin/GHS-R axis plays a potential role in promoting tumor growth and progression through neoangiogenesis, rather than the proliferation of tumor cells.

Pretreatment intratumoral susceptibility signals correlate with response to high-dose methotrexate and progression-free survival in primary central nervous system lymphoma

We aimed to estimate the frequency of intratumoral susceptibility signals (ITSS) in susceptibility-weighted imaging (SWI) in consecutive patients with primary central nervous system lymphoma (PCNSL), and to determine if pretreatment heterogeneity of PCNSL is predictive of response to chemotherapy by using ITSS on SWI. We retrospectively examined 29 immunocompetent patients with PCNSL who underwent SWI-MRI before treatment. A univariate analysis was conducted with Fisher's exact test. Progression free survival (PFS) was calculated by the Kaplan-Meier method and compared by the log rank test. The patients, including 16 males, were initially treated at a median age of 69 years. All tissue types were diffuse large B-cell lymphoma. Nineteen patients (66%) presented lesions with ITSS. Sixteen patients (55%) received initial treatment with R-MTX (rituximab plus high-dose methotrexate). Seven out of nine patients with ITSS exhibited a poor response, whereas all seven without ITSS exhibited a good response to R-MTX. Regarding the absence of ITSS, the sensitivity, specificity, and diagnostic accuracy for a good response to R-MTX were 0.78, 1.00, and 0.88, respectively. Patients without ITSS showed significantly longer PFS compared to patients with ITSS (median PFS: 28.9 vs 2.1 months, P < 0.01). In conclusion, ITSS in PCNSL patients were more common than previously reported. We have to be careful to use ITSS for differentiating PCNSL and glioblastoma. Presence of ITSS correlated significantly with therapeutic response to R-MTX. ITSS may be a new marker for the response to chemotherapy in patients with PCNSL. A prospective multi-institutional analysis is needed.

Delayed Contrast Enhancement in Magnetic Resonance Imaging and Vascular Morphology of Primary Diffuse Large B-Cell Lymphoma (DLBCL) of the Central Nervous System (CNS): A Retrospective Study

Background

This study aimed to compare the magnetic resonance imaging (MRI) findings of primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (CNS) with delayed contrast enhancement and histological microvessel density (MVD). T1-weighted and T2-weighted contrast-enhanced and non-enhanced brain imaging were used. CNS lymphoma tissue was evaluated using primary antibodies to endothelial cells and smooth muscle cells, and histochemical staining for reticulin fibers and basement membrane, which allowed quantification of the MVD.

Material/Methods

Twenty-one patients with histologically confirmed primary DLBCL of the CNS underwent pre-contrast-enhanced and postcontrast-enhanced MRI. Histology of the CNS lymphoma tissue included immunohistochemical staining with antibodies to CD34 for vascular endothelial cells and alpha smooth muscle actin (ASMA) for vascular smooth muscle cells, and histochemical staining included periodic acid-Schiff (PAS) and silver staining for reticulin fibers to evaluate microvessel density (MVD).

Results

In primary DLBCL of the CNS, a positive correlation was found between the degree of necrosis and the size of the lymphoma (r=0.546, P=0.01). Delayed imaging enhancement was significantly correlated with the number of mature vessels, MVD, basement membrane, and reticulin fibers (r=0.593, 0.466, 0.446 and 0.497, respectively). Standardized β regression coefficient analysis showed that the MVD, PAS-positive structures, the number of mature vessels, and reticulin fibers, were significantly associated with delayed enhancement on MRI (β values, 0.425, 0.409, 0.295, and 0.188, respectively).

Conclusions

In primary DLBCL of the CNS, delayed imaging enhancement on MRI may be due to reduced neovascularization and vascular infiltration by lymphoma cells.

Prognostic role of microvessel density in patients with glioma

BACKGROUND

The aim of this study was to systematically evaluate the prognostic role of microvessel density (MVD) in patients with glioma through performing a meta-analysis.

METHODS

Web of Science, EMBASE, PubMed, Cochrane Library, and China National Knowledge Infrastructure were searched for potentially relevant literature. The study characteristics and relevant data were extracted. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled to estimate the prognostic role of MVD in patients with glioma.

RESULTS

Nine studies with 536 patients were included. The pooled HR of higher MVD for overall survival (OS) was 1.64 (95% CI, 1.07-2.50) in patients with glioma. Subgroup analyses were also performed. The pooled HRs of higher MVD in studies from East Asia studies examining high-grade gliomas and studies using anti-CD105 antibodies were 1.99 (95% CI, 1.04-3.80), 1.60 (95% CI, 1.09-2.34) and 2.99 (95% CI, 1.50-5.99), respectively. No significant publication bias was found (P = .592), but significant between-study heterogeneity was observed (I = 80.5%, P <.001) in the meta-analysis.

CONCLUSION

Our results suggested that higher MVD was associated with worse OS in patients with glioma. The findings may assist future research on antiangiogenic therapy and help predict prognosis in glioma. However, due to the limited number of studies, more well-designed studies are warranted to further verify our results.

Evaluation of Endoglin (CD105) expression in pediatric rhabdomyosarcoma

BACKGROUND

The Intratumoral Microvessel Density (IMVD) is commonly used to quantify tumoral vascularization and is usually assessed by pan-endothelial markers, such as CD31. Endoglin (CD105) is a protein predominantly expressed in proliferating endothelium and the IMVD determined by this marker measures specifically the neovascularization. In this study, we investigated the CD105 expression in pediatric rhabdomyosarcoma and assessed the neovascularization by using the angiogenic ratio IMVD-CD105 to IMVD-CD31.

METHODS

Paraffin-embedded archival tumor specimens were selected from 65 pediatric patients affected by rhabdomyosarcoma. The expression levels of CD105, CD31 and Vascular Endothelial Growth Factor (VEGF) were investigated in 30 cases (18 embryonal and 12 alveolar) available for this study. The IMVD-CD105 to IMVD-CD31 expression ratio was correlated with clinical and pathologic features of these patients.

RESULTS

We found a specific expression of endoglin (CD105) in endothelial cells of all the rhabdomyosarcoma specimens analyzed. We observed a significant positive correlation between the IMVD individually measured by CD105 and CD31. The CD105/CD31 expression ratio was significantly higher in patients with lower survival and embryonal histology. Indeed, patients with a CD105/CD31 expression ratio < 1.3 had a significantly increased OS (88%, 95%CI, 60%-97%) compared to patients with higher values (40%, 95%CI, 12%-67%). We did not find any statistical correlation among VEGF and EFS, OS and CD105/CD31 expression ratio.

CONCLUSION

CD105 is expressed on endothelial cells of rhabdomyosarcoma and represent a useful tool to quantify neovascularization in this tumor. If confirmed by further studies, these results will indicate that CD105 is a potential target for combined therapies in rhabdomyosarcoma.

Endothelial Cell Hypertrophy and Microvascular Proliferation in Meningiomas Are Correlated with Higher Histological Grade and Shorter Progression-Free Survival

Microvascular proliferation (MVP) is a hallmark of glioblastoma. Endothelial cell hypertrophy (ECH), also known as endothelial hyperplasia, is correlated with a shorter survival of patients with gliomas. However, the prognostic value of these 2 morphological features has not been studied in meningiomas. The aim of this study was to evaluate the prognostic value of angiogenesis in meningiomas, most notably ECH, MVP, and microvascular density, which were evaluated using immunohistochemistry with antibodies against CD34 and CD105 (a marker of neovascularization) in a series of 139 meningiomas. ECH, MVP, and CD105 immunoreactivity were significantly correlated with higher histological grades (p < 0.0001, p = 0.0004, and p = 0.0003, respectively). ECH and MVP but not CD105 immunoreactivities were significantly correlated with a shorter progression-free survival time (PFS) (p = 0.017, p = 0.021, and p = 0.137, respectively). In Cox multivariate analysis, ECH was an independent predictor of shorter PFS (p = 0.028). Therefore, ECH and MVP are markers of shorter PFS in meningiomas and are significantly correlated with grade. These findings give insight into the use of anti-angiogenic therapies. Further studies are needed to determine whether these markers could allow us to identify patients who could benefit from anti-angiogenic therapies.

Prognostic impact of MYC protein expression in central nervous system diffuse large B-cell lymphoma: comparison with MYC rearrangement and MYC mRNA expression

The prognostic role of MYC has been well documented in non-central nervous system diffuse large B-cell lymphoma; however, it remains controversial in central nervous system diffuse large B-cell lymphoma. To investigate the prognostic value of MYC, we analyzed the MYC protein expression by immunohistochemistry, mRNA expression by RNA in situ hybridization, and gene status by fluorescence in situ hybridization in 74 cases of central nervous system diffuse large B-cell lymphoma. Moreover, we examined the correlation between MYC translocation, mRNA expression, and protein expression. The mean percentage of MYC immunopositive cells was 49%. Using a 44% cutoff value, 49 (66%) cases showed MYC protein overexpression. The result of mRNA in situ hybridization using the RNA scope technology was obtained using the H-scoring system; the median value was 34.2. Using the cutoff value of 63.5, 16 (22%) cases showed MYC mRNA overexpression. MYC gene rearrangement was detected in five out of 68 (7%) cases. MYC translocation showed no statistically significant correlation with mRNA expression; however, all MYC translocation-positive cases showed MYC protein overexpression, with a higher mean percentage of MYC protein expression than that of translocation-negative cases (78 vs 48%, P=0.001). The level of MYC mRNA expression was moderately correlated with the level of MYC protein expression (P<0.001). The mean percentage of MYC protein expression in the high MYC mRNA group was higher than that in the low MYC mRNA group (70 vs 47%, P<0.001). A univariate analysis showed that age over 60 years, Eastern Cooperative Oncology Group (ECOG) performance status ≥2 and MYC protein overexpression were significantly associated with an increased risk of death. MYC translocation and MYC mRNA expression had no prognostic significance. On multivariate analysis, MYC protein overexpression and ECOG score retained prognostic significance.

Endothelin B receptor expression in malignant gliomas: the perivascular immune escape mechanism of gliomas

In order to clarify the role of endothelin B receptors (ETBRs) in gliomas, we analyzed cell cultures and surgical specimens of gliomas using RT-PCR and immunohistochemistry. RT-PCR measured the absolute expression of ETBR mRNA in twelve samples, which included gliomas that were classified using the World Health Organization (WHO) classification system Grade I-IV, as well as two glioblastoma cell lines (CCF-STTG1 and U87-MG). Using immunohistochemistry, 77 glioma specimens were evaluated for their expression of ETBR and infiltrating T lymphocytes, including an analysis of cytotoxic T cells (CTLs) and regulatory T lymphocytes (Tregs). The number of ETBR-positive vessels in the glioblastomas (Grade IV) was significantly higher than in other grades of gliomas (comparisons to Grade IV, Grade I: p = 0.0323, Grade II: p = 0.0009, Grade III: p = 0.0273). The ETBR expression rate (defined as the number of ETBR-positive blood vessels divided by the total number of blood vessels) in the glioblastomas was higher than the ETBR expression rate in the low-grade gliomas (compared to Grade IV, Grade I: p = 0.0132, Grade II: p = 0.0018, Grade III: p = 0.0745). In addition, the cases which had an ETBR expression rate of 50 % or higher exhibited fewer infiltrating CTLs and more infiltrating Tregs compared to the cases with an ETBR expression rate <50 % (CTLs: p = 0.0342; Tregs: p = 0.0175). Isocitrate dehydrogenase 1 (IDH-1) mutations were identified in 21 cases, but there was no correlation between ETBR expression and IDH-1 mutations for any WHO grade. These results suggest that ETBR expression during neo-angiogenesis may interfere with the homing of CTLs around the tumor and be involved in the immune escape mechanism of gliomas.

Primary central nervous system lymphomas and related diseases: Pathological characteristics and discussion of the differential diagnosis

Although primary diffuse large B-cell lymphomas of the CNS are designated as primary CNS lymphomas according to the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissue in 2008, a variety of other lymphomas (Burkitt lymphomas, EBV-positive diffuse large B-cell lymphoma of the elderly) and related diseases (lymphomatoid granulomatosis) that are also found in the CNS have been spotlighted in recent years. The histopathology of primary CNS Burkitt lymphomas mimics that of primary diffuse large B-cell lymphomas of the CNS after steroid administration. Therefore, for correct diagnosis of the involved lymphoma, comprehensive fluorescent in situ hybridization analysis for c-MYC and BCL2 is recommended in all primary CNS lymphoma cases with aggressive clinical course, multifocal involvement of the CNS, and a high proliferation index. The pathological characteristics of primary CNS EBV-positive diffuse large B-cell lymphoma of the elderly have similarities with those of the latency phenotype III, EBV lymphoproliferative disorders that arise in the setting of immunodeficiency. These age-related lymphomas usually occur in elderly immunocompetent patients, and the incidence of this disease was estimated to range from 4.0% to 13.6% of all primary CNS lymphomas. Shorter overall survival has been reported for patients with this disease. Lymphomatoid granulomatosis (LYG) is a systemic, EBV-driven, angiocentric and angiodestructive lymphoproliferative disorder. Primary LYG that shows distinct clinicopathological features compared with systemic LYG was recently reported. Finally, this review focuses on the relationship between primary CNS lymphomas and demyelinating diseases, and the concomitant use of intraoperative cytology and frozen sections that are helpful in rapid intraoperative diagnosis.

Primary Central Nervous System (CNS) Lymphoma B Cell Receptors Recognize CNS Proteins

Primary lymphoma of the CNS (PCNSL) is a diffuse large B cell lymphoma confined to the CNS. To elucidate its peculiar organ tropism, we generated recombinant Abs (recAbs) identical to the BCR of 23 PCNSLs from immunocompetent patients. Although none of the recAbs showed self-reactivity upon testing with common autoantigens, they recognized 1547 proteins present on a large-scale protein microarray, indicating polyreactivity. Interestingly, proteins (GRINL1A, centaurin-α, BAIAP2) recognized by the recAbs are physiologically expressed by CNS neurons. Furthermore, 87% (20/23) of the recAbs, including all Abs derived from IGHV4-34 using PCNSL, recognized galectin-3, which was upregulated on microglia/macrophages, astrocytes, and cerebral endothelial cells upon CNS invasion by PCNSL. Thus, PCNSL Ig may recognize CNS proteins as self-Ags. Their interaction may contribute to BCR signaling with sustained NF-κB activation and, ultimately, may foster tumor cell proliferation and survival. These data may also explain, at least in part, the affinity of PCNSL cells for the CNS.

MYC protein expression in primary diffuse large B-cell lymphoma of the central nervous system

Primary diffuse large B-cell lymphoma of the central nervous system (CNS DLBCL) is a rare, aggressive subtype of DLBCL, the biology of which is poorly understood. Recent studies have suggested a prognostic role of MYC protein expression in systemic DLBCL, but little is known about the frequency and significance of MYC protein expression in CNS DLBCL. Hence, we investigated MYC protein expression profiles of CNS DLBCL and assessed the relationship between MYC expression and a variety of histopathologic, immunophenotypic, genetic, and clinical features. Fifty-nine CNS DLBCL diagnosed at our institution over the past 13 years were evaluated. The majority of cases (80%) showed centroblastic morphology, and 12 (20%) displayed a perivascular pattern of infiltration. According to the Hans criteria, 41 (69%) cases had a non-germinal center B-cell and 18 (31%) had a germinal center B-cell cell-of-origin (COO) phenotype. Mean MYC protein expression was 50% (median: 50%, range: 10-80%). Forty-three cases (73%) showed MYC overexpression (≥ 40%), and 35 (60%) showed MYC/BCL2 coexpression. MYC overexpression was seen in the single case harboring MYC translocation and in the cases showing increased copies of MYC (27%); however, no significant difference in mean MYC expression was seen between groups harboring or lacking MYC aberrations. In our series, age was associated with a significantly increased risk of death, and the perivascular pattern of infiltration was associated with a significantly increased risk of disease progression. Neither MYC expression (with or without BCL2 coexpression) nor other variables, including COO subtype were predictive of clinical outcome. Our findings indicate that the proportion of CNS DLBCL overexpressing MYC is higher compared to systemic DLBCL, and MYC overexpression appears to be independent of genetic MYC abnormalities. Thus, MYC expression and other immunophenotypic markers used for prognostication of systemic DLBCL might not apply to CNS DLBCL due to differences in disease biology.

BCL2 expression in CD105 positive neoangiogenic cells and tumor progression in angioimmunoblastic T-cell lymphoma

The angiogenic microenvironment has been known to be a component of angioimmunoblastic T-cell lymphoma since its initial characterization. We have shown that angioimmunoblastic T-cell lymphoma endothelial cells produce vascular endothelial growth factor-A (VEGFA), and participate in lymphoma progression. In squamous cell carcinoma, endothelial BCL2 expression induces a crosstalk with tumor cells through VEGFA, a major mediator of tumoral angiogenesis. In the present study, we analyzed BCL2 and VEGFA in 30 angioimmunoblastic T-cell lymphomas, using triple immunofluorescence to identify protein coexpression in well-characterized lymphoma cells and microenvironment neoangiogenic endothelial cells. Using quantitative real-time PCR, we assessed mRNA expression levels in laser-microdissected endothelial and lymphoma cells. In lymphoma cells, as in endothelial cells, BCL2 and VEGFA proteins were coexpressed. BCL2 was expressed only in neoangiogenic CD34(+)CD105(+) endothelial cells. In laser-microdissected cells, mRNA studies showed a significant relationship between BCL2 and VEGFA levels in CD34(+) endothelial cells, but not in CD3(+)CD10(+)lymphoma cells, or in CD34(+) endothelial cells from lymph node hyperplasia. Further study showed that, in AITL, BCL2 mRNA levels in CD34(+)CD105(+) neoangiogenic endothelial cells also correlated with microvessel density, International Prognostic Index, Ann Arbor stage, bone marrow involvement and elevated LDH. BCL2 expression by CD105(+) neoangiogenic endothelial cells is related to tumor progression in angioimmunoblastic T-cell lymphoma.

Galectin 1 proangiogenic and promigratory effects in the Hs683 oligodendroglioma model are partly mediated through the control of BEX2 expression

We have previously reported that galectin 1 (Gal-1) plays important biological roles in astroglial as well as in oligodendroglial cancer cells. As an oligodendroglioma model, we make use of the Hs683 cell line that has been previously extensively characterized at cell biology, molecular biology, and genetic levels. Galectin 1 has been shown to be involved in Hs683 oligodendroglioma chemoresistance, neoangiogenesis, and migration. Down-regulating Gal-1 expression in Hs683 cells through targeted small interfering RNA provokes a marked decrease in the expression of the brain-expressed X-linked gene: BEX2. Accordingly, the potential role of BEX2 in Hs683 oligodendroglioma cell biology has been investigated. The data presented here reveal that decreasing BEX2 expression in Hs683 cells increases the survival of Hs683 orthotopic xenograft-bearing mice. Furthermore, this decrease in BEX2 expression impairs vasculogenic mimicry channel formation in vitro and angiogenesis in vivo, and modulates glioma cell adhesion and invasive features through the modification of several genes previously reported to play a role in cancer cell migration, including MAP2, plexin C1, SWAP70, and integrin beta(6). We thus conclude that BEX2 is implicated in oligodendroglioma biology.

Density of microvessels positive for CD105 (endoglin) is related to prognosis in meningiomas

Microvessel density (MVD) is considered to be a prognostic marker in many tumours. Nevertheless, conflicting results were achieved regarding its prognostic role in meningiomas when it was quantified through pan-endothelial markers such as CD34, CD31 or Factor VIII. In the present study, MVD was assessed in meningiomas through the specific marker for neo-angiogenesis CD105. Fifty-four formalin fixed, paraffin embedded, surgical cases of meningiomas (WHO 28 grade I and 26 grade II) as well as ten normal leptomeningeal samples were submitted to immunohistochemical analysis for CD105. CD34 immuno-expression was also evaluated on consecutive parallel sections. For each case, MVD was estimated in terms of number of vessels/mm(2). CD105 was not evidenced in normal samples, whereas it was demonstrated in the vessels within 14/28 WHO grade I cases and within 24/26 WHO grade II meningiomas. On the contrary, CD34 antibody stained blood vessels in both normal and neoplastic samples; moreover, in each case, it stained more microvessels than CD105 antibody (25.33 +/- 21.16 vs. 50.72 +/- 26.75). Higher CD105 counts were significantly correlated with higher histological grade and Ki-67 LI > 4%. No statistical significant correlations were encountered between MVD measured by either CD105 and CD34 and sex, age, site of tumour or extent of surgical resection. CD105-MVD, but not CD34-MVD, showed an inverse significant correlation with overall survival and recurrence-free survival. In conclusion, our study suggests the higher specificity of CD105 in comparison to pan-endothelial markers in the evaluation of meningioma neo-angiogenesis, and its higher prognostic significance. CD105 might serve as a target for therapeutic approaches blocking blood supply in meningiomas.