Positive p16 Immunostaining Is an Independent Prognostic Variable for Disease-free Survival and Overall Survival in Patients With Squamous Cell Carcinoma of the Vulva Treated With Radical Surgery and Inguinofemoral Lymphadenectomy: An Italian Single Center Retrospective Study

BACKGROUND/AIM

The expression of the cyclin-dependent kinase inhibitor p16 correlates with the presence of human papillomavirus. The purpose of this investigation was to assess the prognostic relevance of p16 expression in patients with vulvar squamous cell carcinoma (VSCC) treated with radical surgery followed by adjuvant (chemo) radiation in selected cases.

PATIENTS AND METHODS

Seventy-eight patients were analyzed retrospectively.

RESULTS

Positive p16 immunostaining was detected in 19 (24.4%) patients. Five-year disease-free survival (DFS) and 5-year overall survival (OS) were better in p16-positive compared to p16-negative patients (83.9% versus 37.3% p=0.002 and 91.7% versus 57.6%, p=0.003, respectively). p16 expression retained prognostic relevance at multivariate analysis for both DFS and OS.

CONCLUSION

p16 expression was detected in 24.4% of patients with VSCC and was found to be an independent prognostic variable for both DFS and OS.

Prenatal Environmental Stressors and DNA Methylation Levels in Placenta and Peripheral Tissues of Mothers and Neonates Evaluated by Applying Artificial Neural Networks

Exposure to environmental stressors during pregnancy plays an important role in influencing subsequent susceptibility to certain chronic diseases through the modulation of epigenetic mechanisms, including DNA methylation. Our aim was to explore the connections between environmental exposures during gestation with DNA methylation of placental cells, maternal and neonatal buccal cells by applying artificial neural networks (ANNs). A total of 28 mother-infant pairs were enrolled. Data on gestational exposure to adverse environmental factors and on mother health status were collected through the administration of a questionnaire. DNA methylation analyses at both gene-specific and global level were analyzed in placentas, maternal and neonatal buccal cells. In the placenta, the concentrations of various metals and dioxins were also analyzed. Analysis of ANNs revealed that suboptimal birth weight is associated with placental H19 methylation, maternal stress during pregnancy with methylation levels of NR3C1 and BDNF in placentas and mother's buccal DNA, respectively, and exposure to air pollutants with maternal MGMT methylation. Associations were also observed between placental concentrations of lead, chromium, cadmium and mercury with methylation levels of OXTR in placentas, HSD11B2 in maternal buccal cells and placentas, MECP2 in neonatal buccal cells, and MTHFR in maternal buccal cells. Furthermore, dioxin concentrations were associated with placental RELN, neonatal HSD11B2 and maternal H19 gene methylation levels. Current results suggest that exposure of pregnant women to environmental stressors during pregnancy could induce aberrant methylation levels in genes linked to several pathways important for embryogenesis in both the placenta, potentially affecting foetal development, and in the peripheral tissues of mothers and infants, potentially providing peripheral biomarkers of environmental exposure.

Cervical Adenocarcinoma: A Still Under-investigated Malignancy

BACKGROUND/AIM

The aim of the study was to correlate the expression of mismatch repairs proteins (MMR), programmed-death-ligand1 (PDL-1), and estro-progestinic receptors (ER/PgR) in tissue samples from a series of cervical adenocarcinoma (ADC) patients with their clinicopathological features.

MATERIALS AND METHODS

Thirty-nine ADC specimens were retrospectively retrieved from the Division of Pathology of the University Hospital of Pisa from 2015 to 2021. Histological subtype, grade (G), Silva pattern, presence of lymph vascular space invasion (LVI), and perineural invasion (PNI) were annotated. On representative samples, immunostaining for ER/PgR, MLH1, PMS2, MSH2, MSH6, and PDL-1(sp142) was performed.

RESULTS

Thirty-five ADCs were HPV-associated usual type (24 invasive and 11 in situ), 2 were clear cell type, one was a minimal deviation adenocarcinoma (MDA), and one was an invasive stratified mucin-producing carcinoma (iSMC). ADC associated with LVI were mostly G2-3, whereas those associated also with PNI were G3 with Silva pattern C. No difference in the expression of ER/PgR was observed with a dichotomic age stratification (51 years) of patients. Only 6 ADCs were MMR-deficient, all of them were of the usual type (4 invasive and 2 in situ). The heterodimer MLH-1/PMS2 was the one most frequently altered (5/6), whereas only one case had MSH6 loss. None of ADCs express PDL-1, except iSMC which showed PDL-1 expression >1% in neoplastic cells.

CONCLUSION

Both invasive and in situ usual type ADCs indicate MMR deficiency, highlighting how this could be an early event in tumorigenesis. None of the cases, except for iSMC, express PDL-1.

Lymph-vascular Space Involvement and/or p53 Overexpression Correlated With the Clinical Outcome of Early-stage Endometrial Cancer Patients Treated With Adjuvant Vaginal Brachytherapy

BACKGROUND/AIM

The majority of patients with endometrial cancer (EC) are diagnosed at an early stage and undergo primary surgery, followed by observation or adjuvant therapy according to risk factors on surgical samples. The objective of this study was to assess the correlation between a risk profile represented by the presence of substantial lymph-vascular space involvement (LVSI) and/or p53 overexpression and the clinical outcome of patients with early-stage endometrial cancer (EC) who received adjuvant vaginal brachytherapy (BT).

PATIENTS AND METHODS

This investigation assessed 79 patients who underwent hysterectomy, bilateral salpingo-oophorectomy, and pelvic and/o aortic lymphadenectomy or sentinel lymph node biopsy followed by hypofractionated (HDR)-vaginal BT, using 192Ir source, for stage I-II endometrioid (n=70) or non-endometrioid (n=9) EC. Thirty-four patients (43.0%) were considered to have an unfavorable risk profile defined by the presence of substantial LVSI and /or p53 overexpression.

RESULTS

Five-year disease-free survival (DFS) and five-year overall survival (OS) were 93.7% and 95%, respectively. There was a significant correlation between unfavorable risk-profile and pelvic recurrence rate (p=0.002) and distant recurrence rate (p=0.017). Patients with abnormal p53 had a higher risk of local relapse (p=0.041). Substantial LVSI was strongly associated with pelvic recurrence (p=0.001) and distant metastasis (p<0.001).

CONCLUSION

The presence of substantial LVSI and/or p53 overexpression strictly correlated with poor outcome of patients with early-stage EC and should be taken into consideration for better planning adjuvant treatment in this clinical setting.

Perineural Invasion Correlates With Common Pathological Variables and Clinical Outcomes of Patients With Squamous Cell Carcinoma of the Vulva Treated With Primary Radical Surgery and Inguinal-femoral Lymphadenectomy

BACKGROUND/AIM

The aims of the study were: i) to assess the incidence of perineural invasion (PNI) in squamous cell carcinoma of the vulva and ii) to correlate PNI with common pathological prognostic variables and clinical outcome of patients.

PATIENTS AND METHODS

The hospital records of 64 patients with vulvar squamous cell carcinoma who underwent primary radical surgery were reviewed.

RESULTS

PNI was significantly related to stage (p=0.038), size (p=0.038), lymph-vascular space involvement (p=0.013) and nodal status (p=0.038), but not to patient age, tumor grade and stromal invasion. Five-year disease-free survival was 30.0% in patients with PNI and 53.1% in those without PNI (p=0.018), and the corresponding 5-year overall survival was 50.0% and 77.1% (p=0.031), respectively.

CONCLUSION

PNI was associated with common pathological prognostic variables and with a poorer clinical outcome in patients with vulvar squamous cell carcinoma.

Is Perineural Invasion a Novel Prognostic Factor Useful to Tailor Adjuvant Treatment in Patients Treated With Primary Surgery for Cervical and Vulvar Carcinoma?

Perineural invasion (PNI) is detected in 7.0-35.1% of cervical carcinomas. This histological finding correlates with cervical invasion, lymph-vascular space invasion (LVSI), tumor size, positive resection margins, parametrial invasion, node metastases and advanced stage. Some authors have reported that PNI has no prognostic relevance, others have found that PNI is related to disease-free survival or overall survival (OS) at univariate analysis, and others have observed that it is an independent poor prognostic factor for OS. The evaluation of PNI status should be included in the decision-making process for planning adjuvant treatment. PNI has been found in 7.6-52.4% of vulvar carcinomas. This feature, which is strongly associated with depth of invasion, LVSI, tumor size, advanced stage and nodal involvement, is an independent prognostic variable for the risk of recurrence and death in most series. PNI should be evaluated routinely in histopathology reports of vulvar carcinoma and could help clinicians to tailor adjuvant treatment.

Malignant Transformation in Mature Cystic Teratomas of the Ovary: Case Reports and Review of the Literature

Malignant transformation occurs in 1.5-2% of mature cystic teratomas (MCT)s of the ovary and usually consists of squamous cell carcinoma, whereas other malignancies are less common. Diagnosis and treatment represent a challenge for gynecologic oncologists. The preoperative detection is very difficult and the diagnostic accuracy of imaging examinations is uncertain. The tumor is usually detected post-operatively based on histopathologic findings. This paper reviewed 206 consecutive patients who underwent surgery for a histologically-proven MCT of the ovary between 2010 and 2017. Malignant transformation occurred in 3 (1.5%) of them, and consisted of squamous cell carcinoma in one, type 2 papillary renal carcinoma in one, and papillary thyroid carcinoma in another one. The paper reported the clinical, radiological and histological features of these cases and reviewed the literature data on the treatment options.

The Role of Somatostatin in Vasogenic Meningioma Associated Brain Edema

Many tumors, including meningiomas, express somatostatin receptors, suggesting the application of somatostatin analogues for therapy and diagnosis. Sixty percent of meningiomas are associated with perilesional edema, whose development seems to be related to the vascular endothelial growth factor, although it requires an efficient pial blood supply. However, in several neoplastic models, other mediators seem to cooperate with vascular endothelial growth factor in regulating angiogenesis. We evaluated somatostatin receptors (sst2) in relation to the possibility that somatostatin analogues may influence vascular endothelial growth factor production with reduction of edema. Of 35 studied meningiomas, 21 presented peritumoural edema. Vascular endothelial growth factor, microvascular density and pial blood supply were significantly related to the edema (P = 0.0001, P = 0.0001, P = 0.0005). Similarly, a relation was found between sst2 and microvascular density (r = 0.58, P <0.001) and between sst2 and vascular endothelial growth factor expression (P = 0.03). This suggests that somatostatin analogues may be relevant for the treatment of meningiomas.

Immunohistochemical and Molecular Study of Radiation-Induced Multiple Meningiomas with Pleural and Pulmonary Metastasis

In the present study, the telomerase activity and the putative alterations of genes involved in cell-cycle control (p53, Fas and pRb) were investigated in a radiation-induced meningioma with multiple recurrences and pleural-pulmonary metastases (the patient, a 34-year-old male, had a history of carcinoma of the tongue of testicular lymphocytic lymphoma). Expression of VEGF and vasculature pattern were also studied. Expression of VEGF, pRb and p53 were evaluated by immunohistochemistry on formalin-fixed, paraffin-embedded samples of the tumor. VEGFmRNA was determined by competitive PCR. Fas, FasL and hTERT were evaluated by RT-PCR. Telomerase activity was examined by the TRAP assay. An intense vascularization was observed, supported by high expression of VEGFmRNA (isoforms 121 and 165). pRb and p53 were overexpressed. Fas was undectable with PCR, whereas FasL was positive. Furthermore, the lesion showed an elevated telomerase activity (TPG, 22), according to the high expression of hTERT. These findings emphasized that even among generally benign neoplasms, such as meningiomas, some highly malignant tumors may develop, as in our case, in which several mechanisms were activated in the cancer progression to guarantee the immortalization of cellular clones (angiogenic phenomenon, activation of telomerase and of anti-apoptotic mechanisms) and the blood spread. Thus, the data illustrate the importance of searching for genetic aberrations (which are a hallmark of malignancy) in meningiomas, as predictive and reliable factors of the possibility to recur and to metastasize.

Mammary Fetal Gland: Identification of New Oncofetal Antigens by Monoclonal Antibodies B72.3, MM1.80 and 4.36

Aims and Background

The B72.3, MM1.80 and 4.63 monoclonal antibodies directed against tumor-associated antigens react in human breast also with metaplastic, preneoplastic and metastatic cells, whereas they do not react with normal adult mammary tissue. The aim of our study was to point out the expression of these antigens during mammary gland development, since tumor-associated antigens are known to represent antigens of differentiation.

Study design

Fifty female fetal breasts between 20 and 40 weeks of gestational age were studied.

Results

Mammary tissue was identified only in 15 cases. B72.3, MM1.80 and 4.36 monoclonal antibodies reacted with epithelial antigens and maintained the same location and intensity in the various gestational ages. Immunoreactivity was weak, cytoplasmic and widespread for the 4.36 monoclonal antibody, intense and cytoplasmatic in a large number of cells for the B72.3 monoclonal antibody, and intense and luminal for the MM1.80 monoclonal antibody.

Conclusions

Such data further support the hypothesis that the normal process of development and differentiation can occur during tumor progression processes. Identification of these new oncofetal markers could offer a new perspective able to recognize the different phases of neoplastic progression and could be useful for prevention.

Prognosis of Patients with Gestational Trophoblastic Neoplasia and Obstetric Outcomes of Those Conceiving After Chemotherapy

AIM

To assess prognosis of gestational trophoblastic neoplasia (GTN) and obstetric outcome after chemotherapy.

PATIENTS AND METHODS

Sixty-six patients had diagnosis of hydatiform mole on curettage and 18 developed GTN. Two patients were referred with pathological diagnosis of GTN. Chemotherapy was tailored according to International Federation of Gynecology and Obstetrics risk scoring system.

RESULTS

All patients with GTN but one, were recovered by chemotherapy and had no evidence of disease after a median follow-up of 80 months. Only the patient with epithelioid trophoblastic tumor died of disease. Seven out of the eight women who tried to conceive after chemotherapy became pregnant. Ten conceptions occurred, resulting in no molar pregnancy, three miscarriages and seven term-live healthy births (70.0%). All seven babies showed normal development and growth after a median follow-up of 38 months.

CONCLUSION

The prognosis of women with GTN is very good, and obstetric outcomes of those who conceive after chemotherapy are similar to those of the general population.

MERRF syndrome without ragged-red fibers: the need for molecular diagnosis

We report a patient with myoclonic epilepsy who underwent muscle biopsy for suspected mitochondrial disease (myoclonic epilepsy with ragged-red fibers, MERRF). In spite of normal histochemical studies and of the absence of a severe COX deficiency, the molecular analysis showed the common MERRF mutation (A8344G) in the tRNA(Lys) gene on mitochondrial DNA. The case serves to illustrate the importance of pursuing the proposed mitochondrial genetic abnormality, even in patients with normal biopsy findings.

Expression of endothelin 1 and its angiogenic role in meningiomas

Meningiomas are one of the most frequent central nervous system tumours. Although slow-growing at times, they continue to be a cause of morbidity and mortality. The endothelin (ET) family consists of three isoforms: ET-1 is the most abundant one. ET-1 may be involved in meningioma tumourigenesis in concert with other growth factors, in particular with angiogenic agents. We analysed ET-1 expression by immunohistochemistry and its activating system by reverse-transcription-polymerase chain reaction in 56 cases of meningioma. We found an association between high-grade meningiomas and high ET-1 expression levels (p=0.002). Moreover, we evaluated the potential angiogenic role of ET-1, finding an elevated microvessel count in tumours with high ET expression levels (p=0.004). ET-1 may contribute to meningioma growth by inducing formation of new blood vessels. The finding that ET-1 expression positively correlates with vascular endothelial growth factor (VEGF) expression in meningiomas (p=0.03) also supports the hypothesized modulating effect of ET-1 on angiogenesis. Thus, the influence of the ET system on the progression of meningiomas may occur through stimulation of VEGF. The association of ET-1 and meningioma represents a potential area for therapeutic intervention with selective ET inhibitors. Additional clinical studies will be needed before inhibitors can be incorporated in clinical practice.

Telomerase activity and hTERT mRNA expression in glial tumors

Human telomerase is a structurally complex ribonucleoprotein that is responsible for the maintenance of telomeric DNA at the ends of the chromosomes. The enzyme is proposed as having an important role in cell immortalization and oncogenesis. A limited number of studies have been performed on the telomerase system in brain tumors, and these studies are somewhat conflicting. The relative ineffectiveness of current therapies for malignant gliomas led to the need for novel targets for more promising approaches. In order to clarify the prognostic significance of telomerase expression in gliomas and to speculate on therapeutic implications, we examined telomerase activity by the telomeric repeat amplification protocol (TRAP) assay in 42 gliomas, (32 multiform glioblastomas, 4 anaplastic astrocytomas, 4 differentiated astrocytomas, 1 oligoastrocytoma and 1 oligosarcoma). Telomerase messenger expression (hTERT mRNA) was evaluated by reverse transcription-PCR analysis in the same group of tumors. High telomerase activity was detected in 21/42 gliomas (50%). The levels of telomerase in terms of its messenger level expression overlapped the activity; in fact, a significant association between telomerase activity and hTERT mRNA expression was found (chi2 test; p<0.0001). At univariate analysis, advanced age as well as high telomerase activity and hTERT mRNA levels were seen to be significant predictors of worse prognosis regarding both overall survival (p=0.007, p=0.007, p=0.04, respectively) and disease-free interval (p=0.008, p=0.008, p=0.04, respectively). All these variables maintained a significant independent prognostic role in multivariate analysis. Telomerase may represent an indicator of progression and poor prognosis in this type of cancer, with interesting therapeutic implications.

Distal embolization during primary angioplasty: histopathologic features and predictability

BACKGROUND

Distal embolization during primary percutaneous coronary interventions (PCIs) may affect myocardial reperfusion. We evaluated the prevalence and features of embolization during primary PCI and its relationship with clinical and angiographic variables.

METHODS

Forty-six consecutive patients with acute myocardial infarction underwent primary PCI with a filter-based distal protection device. Histopathologic analysis was performed on retrieved embolic fragments, assessing the presence and relative amount of fibrin, necrosis, lipid droplets, collagen, mucopolysaccharides, and leukocytes, as well as the total debris volume. Such variables were related to baseline clinical and angiographic variables.

RESULTS

Embolic material was recovered in 41 (89%) of 46 cases, with a mean total debris volume of 1.2 +/- 2.2 mm3. Prevalent histopathologic patterns were organized thrombus (47%), fresh thrombus (29%), and plaque fragments (24%). At multivariate analysis, none of the baseline clinical variables considered significantly predicted the total debris volume. Among angiographic variables, angiographic signs of high thrombus burden (cut-off coronary occlusion pattern or large intracoronary minus image) independently predicted the total debris volume at multivariate analysis (odds ratio 15.8, P < .005). Compared with its nonuse, abciximab did not affect the total number and the mean total volume of embolized material (15 +/- 16 vs 10 +/- 8 fragments, 1.5 +/- 2.5 vs 1.0 +/- 1.9 mm3, respectively, for both P > .20), or its qualitative composition.

CONCLUSIONS

Distal embolization occurs in most patients during primary PCI and mainly consists of plaque fragments and partially organized thrombi, which are likely to be scarcely responsive to antiplatelet drugs. Baseline angiographic signs of a high thrombus burden are the only significant predictors of the extent of distal embolization.

Inclusion body myopathy associated with motor neuron syndrome: three case reports

BACKGROUND

Hereditary inclusion body myopathy (h-IBM) is an autosomal-recessive or autosomal-dominant hereditary disease characterized by peculiar findings in muscle biopsies which resemble those occurring in inclusion body myositis (IBM). The absence of an inflammatory infiltrate in myofibers in h-IBM is a relevant differential criterion between the two pathologies. Motor neuron diseases (MND) represent a group of disorders involving both upper and lower motor neurons, characterized by fasciculations, progressive muscle weakness, and muscle atrophy. The most common form and prototype of MND is the amyotrophic lateral sclerosis (ALS) or Charcot's Disease, a progressive and fatal neurodegenerative disorder occurring in late adulthood. The pathogenesis of ALS remains still unknown, a variety of hypotheses having been proposed to account for the disease. The association of both pathologies is not common and offers new hypotheses about the pathogenic mechanisms in skeletal muscle and nervous system degeneration.

PATIENTS AND METHODS

Described are three case reports in which we observed the clinical, laboratory and histopathological association of IBM and MND. In one case, dementia was also present. Muscle data was obtained by muscle biopsies and immunohistochemistry, while diagnosis of MND was supported by common neurophysiological techniques.

RESULTS

The accumulation ofphosphorylated neurofilaments with a hereditary IBM-like pattern in skeletal muscle fibers without accumulation of amyloid-beta protein was observed.

CONCLUSIONS

A better knowledge of the mechanisms in cellular death cascade could explain the pathogenesis of these different degenerative disorders.

A novel mitochondrial tRNAPhe mutation causes MERRF syndrome

A woman with typical features of myoclonic epilepsy with ragged red fibers (MERRF) had a novel heteroplasmic mutation (G611A) in the mitochondrial DNA tRNA phenylalanine gene. The mutation was heteroplasmic (91%) in muscle but undetectable in accessible tissues from the patient and her maternal relatives. Single-fiber PCR analysis showed that the proportion of mutant genomes was higher in cytochrome c oxidase (COX)-negative ragged red fibers (RRFs) than in COX-positive non-RRFs. This report shows that typical MERRF syndrome is not always associated with tRNA lysine mutations.

Angiogenesis in intracranial meningiomas: immunohistochemical and molecular study

Much of the morbidity of intracranial meningiomas is related to the degree of tumour vascularity and the extent of peritumoural vasogenic oedema. Several studies have shown that vascular endothelial growth factor (VEGF) is up-regulated in meningiomas, although its relationship with tumour vasculature is still unclear. In order to better understand the angiogenic assessment of intracranial meningiomas, we analysed its vascular pattern, both as number and as morphologic configuration of microvessels. Moreover, we investigated the mRNA-VEGF expression, relating this expression to vascular pattern. A total of 40 intracranial meningiomas, classified as benign (31 cases), atypical (7 cases), and anaplastic (2 cases) were analysed. RT-PCR analyses of mRNA-VEGF and competitive-PCR were performed. VEGF expression and microvessel density (MVD) were also immunohistochemically investigated. Grade II-III meningiomas showed numerous small microvessels (mean: 34), while the majority of Grade I showed few larger vessels (mean: 13.09) (P = 0.000003). A microvessel pattern overlapping into atypical subtype was found in eignt of the 31 (25.8%) Grade I meningiomas. A significant association was found between grading and vascular pattern (P = 0.0002), as well as between the MVD and the immunohistochemical expression of VEGF (P = 0.0005). The expression of mRNA agreed with the immunohistochemical expression of the protein (P < 0.0001). A total of 39 cases expressed the 121 VEGF isoform and, among these, 28 cases also expressed the 165 isoform. Only 9 cases expressed both isoforms 165 and 189. Grade II and III meningiomas showed a preponderant expression of soluble isoforms (121 and 165). These results prompt us to speculate that the microvessel pattern could underlie a higher metabolic demand, probably due to a rapid growth with a consequent worse clinical behaviour of the tumour. In this sense, the vascular pattern may be used as a prognostic factor, in order to mostly focus attention on those Grade I meningiomas which have a higher likelihood of either recurrence or development of perilesional oedema. The pattern of vasculature itself seems to be dependent on the types of VEGF isoforms: the Grade II-III meningiomas (that presented numerous microvessels) expressed the soluble isoforms 121 and 165, while the isoform 189 was more frequently detected in Grade I meningiomas.

Telomerase in intracranial meningiomas

Telomere length maintenance is essential for tumorigenesis; most human tumors stabilize their chromosome ends via the activity of a specialized reverse transcriptase, telomerase, that uses the template region of the RNA moiety complementary to the TTAGGG repeat to synthesize one strand of telomeric DNA. Meningiomas are estimated to constitute between 13% and 26% of primary intracranial tumors. The aim of this study was to evaluate telomerase activity and its messenger expression in meningiomas in relation to their different histologic pattern and grade of cytonuclear atypies, which are associated with relapse, and consequently represent the most important parameter for the evaluation of the clinical behavior of this tumor. Telomerase activity was examined by the telomeric repeat amplification protocol (TRAP) assay in 32 meningiomas (26 typical and 6 atypical/anaplastic). Telomerase messenger expression (hTERT mRNA) was evaluated by reverse transcription-PCR analysis in the same group of tumors. Telomerase activity ranged from undetectable to low levels in 19/26 (73%) of typical meningiomas, while all the atypical/anaplastic meningiomas showed medium-high levels of activity (>3 TPG units, median value), (chi(2) test; p=0.001). The levels of telomerase in terms of its messenger level expression overlapped the activity; a significant association between telomerase activity and hTERT mRNA expression was also found (chi(2) test; p=0.01). Moreover, 2 atypical/anaplastic meningiomas of our series relapsed; in these samples we found high levels of telomerase, both in terms of activity and mRNA expression. Telomerase activity and its hTERT mRNA expression tended to increase as the histologic grading of intracranial tumors increased, suggesting a role of telomerase reactivation in the progression of these tumors. Moreover, our results indicate RT-PCR assay as a rapid tool to identify and quantify telomerase RNA in intracranial meningiomas as in other human tumor models.

Meningioma-associated brain oedema: the role of angiogenic factors and pial blood supply

BACKGROUND

Approximately 60% of meningiomas are associated with perilesional brain oedema. Several aspects have been evaluated in order to understand the pathophysiological mechanisms of oedema (age, sex of the patient, size and location of the tumour, histotype, grading), although at present they have yet to be completely clarified. We focused on pial blood supply, microvascular density (MVD) and angiogenic growth factors (i.e. vascular endothelial growth factor--VEGF) in order to evaluate their putative role in the development of brain oedema.

METHODS

We retrospectively studied 55 patients with intracranial meningiomas. Computerized tomography (CT) and angiographic studies were obtained in all cases. The angiograms provided an accurate differentiation between pial and dural blood supply, concomitantly with its semi-quantitative evaluation. The location and the volume of oedema, in relation to the meningioma surface, was evaluated using CT scans, as an oedema index (E/I). We also determined the expression of VEGF and MVD using standard immunohistochemical methods.

RESULTS

Thirty-two out of 55 meningiomas presented peritumoural oedema, with an angiographic blush ranging from 2 to 4; VEGF protein was expressed in 27 out of 32 cases, independent of grade or histotype of tumours. In all patients, MVD ranged from 4 to 33.3 vessels (median value: 10.6). A significant relationship was found between the expression of VEGF and MVD (p = 0.0003) and between VEGF and E/I (p = 0.0023). Moreover, the E/I ratio was related to the blush (p = 0.0005). A significant association was also present between VEGF expression and pial blush (p = 0.0001).

CONCLUSION

Our data confirm the central role of VEGF and pial blood supply in the pathogenesis of peritumoural oedema and support the hypothesis that the development of oedema in meningioma is vasogenic in type.

[Mixed neuroglial tumor: description of a case]

A case of neuroglial tumor in a 18-year-old man is presented. The neoplasm was composed by two cell types. One type showed features typical of neuronal cells, while the other resembled glial cells. The diagnosis was confirmed by immunohistochemistry results.

A bactericidal protein in Bombina variegata pachypus skin venom

The skin venom of the yellow bellied toad Bombina variegata pachypus has an antimicrobial activity which seems to be correlated to the presence of a 6700 mol. wt polypeptide. This polypeptide was purified by electroelution from SDS-urea-polyacrylamide gels and characterized for its antimicrobial activity. A bactericidal action was detected at concentrations with little or no cytolytic effect. The determination of the Minimal Inhibitory Concentration showed that there was activity against gram positive and gram negative bacteria and also against yeasts. The skin secretions of three other anuran species (Bufo viridis, Hyla arborea and Discoglossus pictus) were examined for the presence of antimicrobial activities. Only the Hyla arborea secretion exhibited antimicrobial properties. A small amount of a 6700 mol. wt polypeptide was detected among the Hyla secreted products.

Isolation of Bacillus subtilis transformation-deficient mutants and mapping of competence genes

We have isolated and characterized 48 Bacillus subtilis competence-deficient mutants. The mutants, obtained by nitrosoguanidine mutagenesis or by insertional mutagenesis with transposon Tn917, had a reduced transformation frequency and a wild-type transduction frequency. The com mutations were mapped by PBS1 transduction and at least four new com genes have been identified. The mutants were also characterized for their capacity to bind and take up the transforming DNA.