Ipilimumab in the common daily practice: Feasibility, safety, and efficacy in heavily pretreated metastatic melanoma patients

e20002

Background: Effective anti-tumor responses are being observed in metastatic melanoma (MM) patients (pts) with the anti-CTLA-4 antibody Ipilimumab (Ipi) in clinical trials; however no data support the feasibility and clinical effectiveness of Ipi use in the daily practice. We report a single Institution experience utilizing Ipi within a compassionate program for MM pts. Methods: 27 stage III (2) or IV (25) pts (14 males, 13 females), median age 55 (23–77) years, ECOG performance status 0- 1, with MM (23 cutaneous, 3 uveal, 1 mucosal) progressing to 3 median (1–5) systemic therapies for metastatic disease received Ipi. Eight pts had evidence (6) or history (2) of brain metastases and 11 elevated (>1x upper limit of normal [ULN]) LDH. In the induction phase (IF) pts received Ipi (10 mg/kg i.v.) q3 weeks (wks) x 4 cycles; after a 12 wks rest treatment was repeated q12 wks in the maintenance phase (MF). Tumor assessment (TA) per modified World Health Organization criteria was performed at baseline, week (wk) 12 (±2) and wk 24, then every 12 wks. Adverse Events (AE) and immune related AE (irAE) were collected according to Common Terminology Criteria for Adverse Events version 3.0. Results: All pts received at least one Ipi dose, and 18/27 completed the IF. Of the remaining 9 pts, 4 are completing the IF and 5 were withdrawn for AE severity (3 pts) or disease progression (2 pts). Eight pts entered the MF. TA at wk 12 showed partial response (PR) in 1/18 or stable disease (SD) in 5/18 pts. TA at wk 24 showed PR and SD in 3/8 and 5/8 pts, respectively, with an ongoing clinical benefit (SD + PR + CR) of 34% (8/23 pts); these pts are still on treatment. Slow, steady declines in tumor volume and appearance of new lesions with subsequent shrinking of total tumor burden has been observed. One patient had Grade 3 AE (myocardial infarction) and 2 pts had Grade 3 irAE (diarrhoea). Excluding pts who are in IF, to date median overall survival is 27 wks (19–39). Conclusions: Ipi treatment is feasible, safe and clinically effective also in the common daily practice and in heavily pretreated, progressing, MM pts. A sizable proportion of these pts experiences durable clinical benefit.

No significant financial relationships to disclose.

Primary hepatic epithelioid hemangioendothelioma progressively responsive to interferon-alpha: is there room for novel anti-angiogenetic treatments?

Primary hepatic epithelioid hemangioendothelioma (HEH) is a rare, low-grade malignant neoplasm of endothelial origin, with an unpredictable clinical course and prognosis. No standard therapeutic strategies are still available for HEH, due to the infrequency of the disease and to its variable natural history that limit the identification of the most effective treatment. In the absence of metastatic disease, surgical resection or liver transplantation represent the treatment of choice for HEH, while several antineoplastic agents have been proposed in the presence of metastatic nonresectable disesase. Herein, we describe the biological characterization and the clinical course of a primary HEH progressively responsive to treatment with intermediate doses of interferon-alpha (IFN)-alpha2a. Furthermore, based on the newly-identified expression of endoglin (CD105) on HEH, we discuss the clinical potential of novel anti-angiogenetic approaches to the disease.

Intracranial Haemorrhage in Patients on Antithrombotics: Clinical Presentation and Determinants of Outcome in a Prospective Multicentric Study in Italian Emergency Departments

BACKGROUND

Intracranial haemorrhage (ICH) is the type of stroke associated with the highest death rate, and about 30% of ICH occurs in patients on antithrombotic treatment. This study relates clinical presentations and outcome of ICH patients on oral anticoagulant (OA) or antiplatelet (AP) therapy admitted to 33 Italian emergency departments (ED).

METHODS

Consecutive patients were enrolled after cranial computed tomography (CT). Primary outcome was the Modified Rankin Scale (MRS) score at 3 months of follow-up. Common descriptive statistics were computed after stratification for traumatic or spontaneous ICH and identification of the anatomical location of bleeding. Multivariate logistic regression was used to assess predictors of death.

RESULTS

We recruited 434 patients on AP therapy and 232 on OA. There were 432 spontaneous and 234 traumatic ICH patients. The proportions of AP and OA patients undergoing neurosurgery were 21.8 and 19.4%, respectively, while < 30% underwent procoagulant medical treatment. At the 3-month follow-up, the case fatality rate was 42.0%, while disability or death (MRS 3-6) was 68.1%. The odds ratio for death in OA versus AP patients was 2.63 (95% CI 1.73-4.00) in the whole population and 2.80 (95% CI 1.77-4.41) in intraparenchymal event patients. Glasgow Coma Scale, age, spontaneous event and anticoagulant use were found to be predictors of death both in traumatic and spontaneous events.

CONCLUSION

This study confirms the high prevalence of death or disability in OA and AP patients with ICH. As far as the determinants of mortality and disability are concerned, the results of this study might be useful in the clinical management and allocation of resources in the ED setting. The observed low use of procoagulant therapy highlights the need for ED educational programmes to heighten the awareness of available and effective haemostatic treatments.

Emerging role of endoglin (CD105) as a marker of angiogenesis with clinical potential in human malignancies

Angiogenesis is crucial for tumor development and progression, and antiangiogenetic therapy represents a promising approach for cancer treatment. Thus, the in-depth understanding of the molecular mechanism(s) regulating angiogenesis, together with the characterization of molecules expressed by endothelial cells and involved in distinct steps of the angiogenetic process, will greatly improve the design of new and more effective therapeutic strategies in human malignancies. Endoglin (CD105), a cell membrane glycoprotein predominantly expressed on cellular lineages within the vascular system, and over-expressed on proliferating endothelial cells, is involved in blood vessels development and represents a powerful marker of neovascularization. CD105 binds several factors of the Transforming Growth Factor (TGF)-beta superfamily, a pleiotropic cytokine that regulates different cellular functions including proliferation, differentiation and migration. In human malignancies of different histotype, CD105 is highly expressed on endothelial cells of both peri- and intra-tumoral blood vessels, while it is weakly expressed or absent on neoplastic cells. This unique tissue distribution strongly suggests for a prognostic, diagnostic and therapeutic potential of CD105 in neoplastic diseases. In this review we will summarize the structural and functional features of CD105, as well as its tissue distribution in normal and neoplastic tissues. Furthermore, the practical implications of CD105 in human malignancies will also be discussed.

Endoglin (CD105): a target for anti-angiogenetic cancer therapy

Targeting of tumor vasculature is a promising strategy for cancer treatment. Among endothelial cell markers, Endoglin, a cell membrane glycoprotein, is emerging as an attractive therapeutic target on angiogenetic blood vessels, and it currently represents a powerful marker to quantify tumor angiogenesis. In normal human tissues, Endoglin is weakly expressed on erytroid precursors, stromal cells and activated monocytes, whereas it is strongly expressed on proliferating endothelial cells. In human neoplasias of different histotype, Endoglin is mainly present on endothelial cells of both peri- and intra-tumoral blood vessels, while it is weakly expressed or absent on neoplastic cells. Endoglin is an accessory component of the receptor complex of Transforming Growth Factor (TGF)-beta, a pleiotropic cytokine that modulates angiogenesis by the regulation of different cellular functions including proliferation, differentiation and migration. Interestingly, the over-expression of Endoglin antagonizes several cellular responses to TGF-beta1, while its down-regulation potentiates cellular responses to TGF-beta1. In animal models, administration of radiolabeled anti-Endoglin monoclonal antibodies (mAb) efficiently images primary tumors, and naked or conjugated anti-Endoglin mAb suppress angiogenesis and tumor growth. In this review we will summarize the complex of experimental evidences pointing to Endoglin as a vascular target to design innovative bioimmunotherapeutic strategies in human neoplasias.

Cancer testis antigens expression in mesothelioma: role of DNA methylation and bioimmunotherapeutic implications

Recent evidences suggest that malignant mesothelioma may be sensitive to immunotherapy; however, little is known about malignant mesothelioma-associated tumour antigens. Focusing on cancer/testis antigens, the expression of well-characterised immunogenic tumour-associated antigens was investigated in malignant mesothelioma cells. At variance with MAGE-4 and NY-ESO-1, malignant mesothelioma cells frequently expressed MAGE-1, -2 and -3, GAGE 1-2, GAGE 1-6, SSX-2 and SSX 1-5, and distinct malignant mesothelioma cells concomitantly expressed at least four cancer/testis antigens. Additionally, the tumour-associated antigens RAGE-1 was expressed at high levels in both benign and malignant mesothelial cells. Lastly, treatment with the DNA hypomethylating agent 5-aza-2'-deoxycytidine induced and up-regulated the expression of the cancer/testis antigen examined in malignant mesothelioma cells. Overall, these findings strongly suggest that cancer/testis antigens-based immunotherapy may represent a suitable therapeutic approach to malignant mesothelioma, and foresee the clinical use of 5-aza-2'-deoxycytidine to design new chemo-immunotherapeutic strategies in malignant mesothelioma patients.

Endoglin: An accessory component of the TGF-beta-binding receptor-complex with diagnostic, prognostic, and bioimmunotherapeutic potential in human malignancies

Endoglin (CD105) is a cell membrane glycoprotein over-expressed on highly proliferating endothelial cells in culture, and on endothelial cells of angiogenetic blood vessels within benign and malignant tissues. CD105 binds several factors of the Transforming Growth Factor (TGF)-beta superfamily, and its over-expression modulates cellular responses to TGF-beta1. The complex of experimental findings accumulated in the last few years strongly indicate that CD105 is a powerful marker of angiogenesis, and that it might play a critical role in the pathogenesis of vascular diseases and in tumor progression. In this paper, we will review the structural, biological and functional features of CD105, as well as its distribution within normal and neoplastic tissues, emphasizing its foreseeable role as a molecular target for new diagnostic and bioimmunotherapeutic approaches in human malignancies.

Bioimmunotherapeutic targets on angiogenetic blood vessels in solid malignangies

Physiological angiogenesis is a tightly regulated process that occurs mainly during reproduction, development and wound healing. Although angiogenesis is a continuous process, different consecutive steps can be identified, including: i) release of pro-angiogenetic factors; ii) release of proteolytic enzymes; iii) endothelial cell migration, morphogenesis and proliferation. Angiogenesis is also a hallmark of malignant diseases, and an inverse correlation between tumor vascularity and survival was demonstrated. Thus, strategies aimed at interfering with tumor blood supply by targeting tumor vasculature, presently represent promising new approaches for the treatment of solid malignancies. In fact, at least 30 angiogenetic inhibitors, utilized alone or in combination with other therapeutic agents, are currently being tested in clinical trials in humans. In this paper, we will review current knowledges on selected molecules expressed by endothelial cells and involved in distinct steps of the angiogenetic process, that represent potential targets for bioimmunotherapeutic approaches in human malignancies.

Unbalanced expression of HLA-A and -B antigens: a specific feature of cutaneous melanoma and other non-hemopoietic malignancies reverted by IFN-gamma

Conflicting evidences suggested that levels of HLA-A and -B antigens expressed on normal and neoplastic cells of given individuals are genetically predetermined, or, on the other hand, regulated by molecular mechanisms generating the down-regulated expression of HLA-B antigens frequently observed on melanoma cells. In our study, we quantitated, both at the protein and mRNA level, the amounts of HLA-A and -B antigens constitutively expressed on 23 primary cultures of metastatic melanomas and on autologous peripheral blood mononuclear cells (PBMC). Flow cytometric analyses identified a significantly (p < 0.01) lower expression of HLA-B antigens on melanoma cell cultures but not on autologous PBMC. Consistently, lower amounts of HLA-B antigens mRNA were detected by RNase protection assay exclusively in neoplastic cells. This unbalanced expression of HLA-A and -B antigens was readily reverted by interferon (IFN)-gamma but not by the DNA hypomethylating agent 5-aza-2'-deoxycytidine in 4 melanoma cell cultures investigated. Significantly (p < 0.05) lower levels of HLA-B antigens were also detected on cells from solid malignancies of different histotypes but not on neoplastic cells from hemopoietic neoplasms; levels of HLA-B antigens were rapidly up-regulated by IFN-gamma exclusively on non-hemopoietic transformed cells. Together, these data strongly argue against a genetic predetermination of the amounts of HLA-A and -B antigens expressed on normal and neoplastic cells of distinct melanoma patients and suggest that constitutively low levels of HLA-B antigens are a specific feature of non-hemopoietic transformed cells that is controlled by common regulatory mechanism(s) and that is possibly shared by non-hemopoietic normal cells.

Overexpression of protectin (CD59) down-modulates the susceptibility of human melanoma cells to homologous complement

The clinical efficacy of therapeutic complement (C)-activating monoclonal antibodies (mAb) to melanoma-associated antigens can be impaired by the levels of expression of C-inhibitory molecules on neoplastic cells. Protectin (CD59) is a glycosylphosphatidylinositol (GPI)-anchored cell membrane glycoprotein, acting as terminal regulator of C cascade, which is heterogeneously expressed in melanomas and represents the main restriction factor of C-mediated lysis of melanoma cells. Thus, we investigated whether the overexpression of CD59 could influence the constitutive susceptibility of distinct melanoma cells to homologous C. Infection of CD59-positive Mel 100 and 70-W melanoma cells by a retroviral vector carrying the CD59 cDNA, significantly (P < 0.05) upregulated their constitutive expression of CD59, whereas it did not affect that of additional C-regulatory molecules. Transduced CD59 was entirely GPI-anchored and showed a molecular weight identical to native CD59. Additionally, higher amounts of soluble CD59 were detected in the conditioned media of CD59-transduced melanoma cells compared with parental cells. CD59-transduced melanoma cells, sensitized by the anti-GD3 disialoganglioside mAb R24, were significantly (P < 0.05) less susceptible to homologous C-lysis than were parental cells; this effect was fully reverted by the masking of CD59 with F(ab')(2) fragments of the anti-CD59 mAb YTH53.1. These results provide conclusive evidence demonstrating that absolute levels of CD59 expression regulate the susceptibility to homologous C of specific melanoma cells, and suggest an additional explanation for the poor clinical results obtained with C-activating mAb in the clinical setting.

Emerging role of protectin (CD59) in humoral immunotherapy of solid malignancies

Over the past two decades, complement (C)-activating monoclonal antibodies (mAb), directed to specific tumor-associated antigens (TAA), have been extensively utilized for passive immunotherapy of solid tumors of different histology. However, the clinical outcome of this therapeutic approach has been substantially disappointing; antigenic heterogeneity of neoplastic cells and their limited accessibility by therapeutic mAb, have been provided as substantial explanations for the poor clinical results obtained. Nevertheless, in light of the recent advances in the knowledge of the mechanisms regulating C-activity, it begins to be evident that membrane and soluble C-inhibitory proteins play a key role in the protection of neoplastic cells from C-attack, providing additional insights on biological features of transformed cells that may hamper the clinical efficacy of humoral immunotherapy. Among C-regulatory proteins investigated, this review will focus on protectin (CD59) that represents the main restriction factor of C-susceptibility of neoplastic cells from solid malignancies. In view of the functional role of CD59, we will describe its tissue distribution and biological features in malignant neoplasms; major emphasis will be given to cutaneous melanoma, in which the C-regulatory role of CD59 has been extensively investigated, and clinical approaches of humoral immunotherapy have been implemented. According to the available data, the foreseeable strategies to improve the therapeutic efficacy of humoral immunotherapy of solid malignancies will be discussed.

Endoglin is a suitable target for efficient imaging of solid tumors: in vivo evidence in a canine mammary carcinoma model

Increasing evidence suggests that endoglin (CD105) is a new powerful marker of neovascularization in solid malignancies; thus, using breast cancer as a model, we investigated whether targeting of CD105 by monoclonal antibody (mAb) MAEND3 can be used for in vivo imaging of solid tumors. Immunohistochemistry and flow cytometry identified differential expression of CD105 on breast cancer and endothelial cells; in fact, neoplastic cells were weakly and rarely stained by mAb MAEND3, which in contrast, strongly and invariably stained blood vessel endothelia within the breast adenocarcinomas investigated and cultured endothelial cells. Moreover, in contrast to CD31, which currently represents the reference marker to assess angiogenetic activity, CD105 expression was highest in semiconfluent and actively proliferating endothelial cells, and it progressively decreased as cells reached tight confluency and low [3H]thymidine uptake. i.v. administration of 18 MBq of 125I-labeled mAb MAEND3 efficiently imaged spontaneous mammary adenocarcinomas in two dogs; the uptake of radiolabeled mAb was rapid and intense because tumor: background ratios of 8.2:1 and 9.3:1 were reached 8 h after mAb administration, in the absence of immediate and/or long-term clinical side effects. Altogether, our present data suggest that targeting of CD105 on tumor-associated blood vessels may represent a new strategy for in vivo imaging of solid malignancies, regardless of their histological origin.

Differential levels of soluble intercellular adhesion molecule-1 (sICAM-1) in early breast cancer and benign breast lesions

To date, no soluble markers can discriminate benign from malignant breast lesions; therefore, to assess the diagnostic potential of circulating intercellular adhesion molecule-1 (sICAM-1), serum concentrations of sICAM-1 were quantitated in 230 consecutive patients that underwent surgery for breast neoplasias, utilizing an enzyme-linked immunosorbent assay. Histological diagnosis revealed that 177 patients had breast cancer and 53 had a benign breast disease. In the cancer patient group, 90 subjects had pT1 tumors without (pT1N0M0, n = 46) or with (pT1N1M0, n = 41; pT1N2M0, n = 3) regional lymph node metastases. Mean levels of serum sICAM-1 of patients with pT1 breast cancer, without or with regional lymph node involvement, were significantly (P < 0.05) higher than those of patients with benign breast lesions and of 49 age-matched control subjects. Elevated levels of serum sICAM-1 were detected in 27/90 (30%) pT1 breast tumors and in 1/53 (2%) benign breast lesions; thus, among subjects with high levels of sICAM-1, 96% had breast cancer. No significant correlation was found between levels of serum sICAM-1 and breast cancer progression. These observations, altogether, suggest that in the presence of a suspicious breast neoplasm the quantitative analysis of serum sICAM-1 can orient clinical diagnosis towards malignancy.

The overlooked "nonclassical" functions of major histocompatibility complex (MHC) class II antigens in immune and nonimmune cells

Besides their "classical" antigenic peptide-presenting activity, major histocompatibility complex (MHC) class II antigens can activate different cellular functions in immune and nonimmune cells. However, this "nonclassical" role and its functional consequences are still substantially overlooked. In this review, we will focus on these alternative functional properties of MHC class II antigens, to reawaken attention to their present and foreseeable immunobiologic and pathogenetic implications. The main issues that will be addressed concern 1) the role of MHC class II molecules as basic components of exchangeable oligomeric protein complexes with intracellular signaling ability; 2) the nonclassical functions of MHC class II antigens in immune cells; 3) the pathogenetic role of MHC class II antigens in inflammatory/autoimmune and infectious disease; and 4) the functional role of MHC class II antigens in solid malignancies.

Prolonged upregulation of the expression of HLA class I antigens and costimulatory molecules on melanoma cells treated with 5-aza-2'-deoxycytidine (5-AZA-CdR)

The immunogenic potential of melanoma cells and their recognition by the host's cytotoxic cells depends on the presence and on the level of expression of human leukocyte antigen (HLA) class I antigens, costimulatory molecules and melanoma-associated antigens (MAA), on neoplastic cells. In this study, we demonstrate that the DNA hypomethylating agent 5-aza-2'-deoxycytidine (5-AZA-CdR), significantly (p < 0.05) enhanced the constitutive expression of HLA class I antigens, HLA-A1 and -A2 alleles, and of the costimulatory molecules intercellular adhesion molecule-1 and lymphocyte function-associated antigen-3, on a panel of 12 melanoma cells. This upregulation peaked at day 4, slowly decreased thereafter, and returned to baseline levels 32 days after the end of treatment. In addition, treatment with 5-AZA-CdR induced a persistent expression of MAGE-1 in Mel 275 melanoma cells; this was still detectable, by reverse transcriptase polymerase chain reaction, 60 days after the end of treatment. In contrast, 5-AZA-CdR did not affect the constitutive expression of the high molecular weight-MAA by the melanoma cells investigated. These observations, together with data obtained comparing the effect of 5-AZA-CdR with that of interferon-gamma, strongly suggest that 5-AZA-CdR may have prospective therapeutic implications in active and/or passive specific immunotherapy for human melanoma.

Structure, distribution, and functional role of protectin (CD59) in complement-susceptibility and in immunotherapy of human malignancies (Review)

Protectin (CD59) is a glycosyl-phosphatidylinositol-anchored cell membrane glycoprotein, ubiquitously expressed, though to a different extent, on benign and malignant cells. CD59 inhibits complement (C)-mediated lysis of target cells by preventing the formation of the membrane attack complex, in the terminal step of C-activation. Recent experimental evidence demonstrates that CD59 is the main restriction factor of C-mediated lysis of malignant cells of different histotype. Additionally, a soluble form of CD59, that retains its anchoring ability and functional properties, has been most recently identified in body fluids and in culture supernatants of different malignant cells. In view of its functional role, CD59 may protect neoplastic cells from C-mediated lysis, contributing to their escape from innate C-control and to tumor progression; additionally, the expression of CD59 by neoplastic cells may contribute to impair the therapeutic efficacy of C-activating monoclonal antibodies (mAb) directed to tumor-associated antigens. In the light of the functional role of CD59, this review focuses on the structural features, tissue distribution and regulation of the expression of CD59 in malignant tissues, and on the foreseeable application(s) of CD59 to improve the therapeutic efficacy of clinical approaches of humoral immunotherapy with C-activating mAb in human malignancies.

Intercellular adhesion molecule-1 is upregulated via the protein kinase C pathway in human thyroid carcinoma cell lines

Nonantigen specific adhesion systems lymphocyte function-associated antigen 1/intercellular adhesion molecule (LFA-1/ICAM-1) and cluster designation 2/lymphocyte function-associated antigen 3 (CD2/LFA-3) are considered a crucial step in immune-mediated cell-cell adhesion reactions. In particular, the LFA-1/ICAM-1 system is deeply involved in major histocompatibility system (MHC)-restricted and non-MHC-restricted cellular cytotoxicity of effector cells against cancer tissues. We have investigated in human thyroid carcinoma cell lines the role of the protein kinase C (PKC) pathway on ICAM-1 expression. Incubation with tissue plasminogen activator (TPA), an agonist of PKC, of two papillary (NPA and TPC-1) and one anaplastic (ARO) carcinoma cell lines induced an ICAM-1 upregulation of both protein and mRNA production. This phenomenon was dependent on RNA and protein synthesis and was inhibited by PKC antagonists such as staurosporine and H-7. A parallel increase in the soluble form of ICAM-1 followed the upregulation of cellular ICAM-1 levels induced by TPA. In conclusion, the PKC pathway is involved in the regulation of ICAM-1 expression in human thyroid carcinoma cell lines. Further studies are necessary to clarify the effects of the PKC pathway on the diffusion of thyroid tumors.

Lateral ventricle subependymomas. Case report taking into particular consideration the aspects of magnetic resonance and review of the literature

Subependymomas are rare neuroectodermic tumours. The authors report a case of a patient he had a subendymoma in the left lateral ventricle, with particular attention to the MR aspects on these lesions and review of the literature.

Melanoma cells constitutively release an anchor-positive soluble form of protectin (sCD59) that retains functional activities in homologous complement-mediated cytotoxicity

Protectin (CD59), a glycosylphosphatidylinositol-anchored cell membrane glycoprotein, is differentially expressed on melanocytic cells and represents the main restriction factor of C-mediated lysis of melanoma cells. In this study, we report that CD59-positive melanoma cells constitutively release a soluble form of CD59 (sCD59), and that its levels directly correlate (r = 0.926; P < 0.05) with the amount of membrane-bound CD59. SDS-PAGE analysis showed that the molecular components of sCD59 are similar to those of cellular CD59 expressed by melanoma cells. Melanoma-released sCD59 is anchor positive since it inserts into cell membranes of homologous cells that transiently increase their expression of CD59. Moreover, sCD59 is functional: it blocks the binding of the anti-CD59 mAb YTH53.1 to melanoma cells and reverses its effects on C-mediated lysis. In fact, preincubation of mAb YTH53.1 with scalar doses of conditioned media of CD59-positive but not of CD59-negative melanoma cells reduced significantly (P < 0.05), and in a dose-dependent fashion, the enhancement of C-mediated lysis of anti-GD3-sensitized melanoma cells induced by the masking of cellular CD59 by mAb YTH53.1. Altogether, these data demonstrate that CD59-positive human melanoma cells release a soluble form of CD59 that is structurally similar to cellular CD59, retains its anchoring ability, is functional, and may impair the effectiveness of clinical approaches to humoral immunotherapy for human melanoma.

Biphasic control of NF-kappa B activation induced by the triggering of HLA-DR antigens expressed on B cells

The regulation of NF-kappa B activation following the triggering of HLA-DR antigens by mAb L243 has been studied at various times in Raji cells. Electrophoretic mobility shift assays demonstrated a strong increase of NF-kappa B DNA binding after triggering of HLA-DR antigens. Using TNF-alpha-activity neutralizing antibodies, the authors demonstrated that the upregulation of NF-kappa B was found to depend, at later time point, on an autocrine effect of TNF-alpha secreted following triggering of HLA-DR antigens. In contrast, it was found to be TNF-alpha independent in the early time point. Moreover, the upregulation of NF-kappa B binding activity is regulated by the triggering of selected epitopes of HLA-DR antigens. In fact, mAb L243 but not the staphylococcal superantigens, staphylococcal exotoxin toxic shock syndrome toxin-I or staphylococcal enterotoxin B, regulate the NF-kappa B binding activity.

Triggering of HLA-DR antigens differentially modulates tumor necrosis factor alpha release by B cells at distinct stage of maturation

Triggering of HLA class II antigens by the anti-HLA-DR monoclonal antibody (mAb) L243 significantly (P < 0.05) and differentially enhanced the release of tumor necrosis factor alpha (TNF-alpha) by the non-Hodgkin's lymphoma cells Ri-I, Ci-I, and Sc-I, which are at a distinct stage of B-cell differentiation, and by the more mature Burkitt lymphoma cell Raji; in contrast, it did not induce TNF-alpha release by the pre-B leukemia cells Nalm-6 and BV173. TNF-alpha release peaked at 24 h and decreased thereafter, and it was dose dependent and preceded by an increase of TNF-alpha mRNA detectable after 3 h of stimulation with mAb L243. Secreted TNF-alpha mediated the enhancement of nuclear factor kappa B (NF-kappa B) and activator protein-1 (AP-1) binding activity; in fact, the triggering of HLA-DR antigens in the presence of antihuman TNF-alpha-neutralizing antibodies did not upregulate NF-kappa B and AP-1. In contrast, released TNF-alpha was not responsible for the homotypic aggregation of Ri-I, Ci-I, Sc-I, and Raji cells induced by mAb L243, and it did not affect the proliferation of B cells investigated. Altogether, our data demonstrate that: (a) the ability of B cells to release TNF-alpha after triggering of HLA-DR antigens depends on their stage of differentiation; (b) levels of released TNF-alpha seem to correlate with the stage of B-cell maturation but do not correlate with the amounts of cell surface HLA-DR antigens; (c) secreted TNF-alpha regulates the levels of expression of NF-kappa B and AP-1 by an autocrine loop; and (d) intracellular signals mediating TNF-alpha release by B cells are distinct from those regulating homotypic aggregation and proliferation.

Tumour-derived interleukin 1alpha (IL-1alpha) up-regulates the release of soluble intercellular adhesion molecule-1 (sICAM-1) by endothelial cells

Levels of circulating soluble intercellular adhesion molecule-1 (sICAM-1) are elevated in patients affected by solid malignancies; however, the cellular sources generating high levels of sICAM-1 remain to be characterized. Using conditioned media (CM) from seven ICAM-1-positive or -negative neoplastic cells, we demonstrate that tumour-derived interleukin 1alpha (IL-1alpha) significantly (P < 0.05) up-regulates the release of sICAM-1 by human umbilical vein endothelial cells. The intensity of the effect correlated with the amounts of IL-1alpha detectable in CM. Levels of ICAM-1 mRNA were also up-regulated by tumour-secreted IL-1alpha. The up-regulation of the shedding of sICAM-1 and of its expression at protein and mRNA level were completely reversed by the addition of anti-IL-1alpha neutralizing antibodies. Consistent with the in vitro data, tumour endothelia were strongly stained for ICAM-1 compared with autologous normal tissue endothelia. Taken altogether, our observations reveal an IL-1alpha-mediated tumour-endothelium relationship sustaining the shedding of sICAM-1 by endothelial cells. This is a general phenomenon in solid malignancies that correlates with the ability of neoplastic cells to secrete IL-1alpha rather than with their expression of ICAM-1 and/or histological origin. sICAM-1 has been previously shown to inhibit LFA-1/ICAM-1-mediated cell-cell interactions; therefore, the ability of neoplastic cells to secrete IL-1alpha is likely to represent a mechanism for their escape from immune interaction.

Melanoma-associated hypopigmentation: where are the antibodies?

Antibodies to the B16 melanoma cell line and to tyrosinase have been recently defined in our laboratory in sera of patients with vitiligo, melanoma, melanoma-associated hypopigmentation (MAH), and in healthy subjects. The antibody titers in each subject were measured by enzyme-linked immunosorbent assay, were compared with the mean optical density (OD) of the control group, and were expressed as relative OD. The titers of anti-B16 antibodies (relative OD +/- standard error) were 1.000 (0.058) in the controls, 1.025 (0.077) in patients with metastatic melanoma, 0.5862 (0.15) in MAH, 1.377 in surgery-induced MAH, 1.087 in vaccination with anti-idiotypic antibodies, and 2.098 (0.15) in autoimmune vitiligo. The titers in vitiligo were significantly higher (p < 0.0001) than in MAH or in healthy controls. Antityrosinase antibodies were found in titers of 1.000 (0.1024) in the controls, 1.516 (0.225) in metastatic melanoma, 1.027 (0.180) in MAH, 1.075 in surgery-induced MAH, 2.308 in vaccination-induced MAH, and 4.536 in vitiligo. Differences were found between vitiligo and MAH (p = 0.008), surgery-induced MAH (p = 0.009), vaccination-induced MAH (p = 0.059), and healthy subjects (p < 0.0001). The results of this study point to the cross-antigenicity between melanocytes and melanoma cells, and to participation of antibodies against melanoma-associated membrane antigens in the mechanism leading to the development of MAH in patients with melanoma.

Expression and structural features of endoglin (CD105), a transforming growth factor beta1 and beta3 binding protein, in human melanoma

Human endoglin (CD105) is a member of the transforming growth factor beta (TGF-beta) receptor family that binds TGF-beta1 and -beta3, but not TGF-beta2, on human endothelial cells. Immunohistochemical analyses demonstrated that CD105 is expressed on normal and neoplastic cells of the melanocytic lineage. The anti-CD105 MAb, MAEND3, stained 50, 25 and 34% of intradermal naevi, primary and metastatic melanomas investigated, respectively, and nine out of 12 melanoma cell lines. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that CD105 expressed by melanoma cells consists of a homodimeric protein with an apparent molecular weight of 180 and 95 kDa under non-reducing and reducing conditions. Cross-linking of 125I-labelled TGF-beta1 to melanoma cells, Mel 97, by disuccinimidyl suberate (DSS) demonstrated that CD105 expressed on pigmented cells binds TGF-beta1; the pattern of binding of TGF-beta1 to melanoma cells was found to be similar to that of human umbilical vein endothelial cells. The addition of exogenous, bioactive TGF-beta1 significantly (P<0.05) inhibited the growth of CD105-positive melanoma cells, Mel 97, but did not affect that of CD105-negative melanoma cells, F0-1. These data, altogether, demonstrate that CD105 is expressed on pigmented cells and might play a functionally relevant role in the biology of human melanoma cells by regulating their sensitivity to TGF-betas.

Triggering of target of an antiproliferative antibody-1 (TAPA-1/CD81) up-regulates the release of tumour necrosis factor-alpha by the EBV-B lymphoblastoid cell line JY

Target of an antiproliferative antibody-1 (TAPA-1/CD81) has been shown to be non-covalently associated to HLA-DR antigens on the cell surface of B cells. In this study the authors report that triggering of CD81 by MoAb 5A6 or 1D6 significantly (P < 0.05) up-regulates the release of tumour necrosis factor-alpha (TNF-alpha) by the Epstein-Barr virus-positive (EBV)-B lymphoblastoid cell line JY. The accumulation of TNF-alpha in the culture medium of JY cells incubated with either anti-CD81 MoAb was found to be dose-dependent and similar to that obtained following crosslinking of HLA-DR antigens with MoAb L243. The effect of the combination of anti-CD81 and anti-HLA-DR MoAb on the release of TNF-alpha by JY cells was not synergistic or additive. In addition, the combination of anti-CD81 and anti-HLA-DR MoAb did not affect proliferation and homotypic aggregation of JY cells induced by each MoAb used alone. Both anti-CD81 or anti-HLA-DR MoAb induced protein tyrosine phosphorylation. However, different cytoplasmic proteins were phosphorylated following triggering of either molecule. Taken together, the data demonstrate that CD81 and HLA-DR antigens induce similar effector phenomena in the regulation of TNF-alpha release, homotypic aggregation and inhibition of JY cell proliferation.

Levels of cell membrane CD59 regulate the extent of complement-mediated lysis of human melanoma cells

Normal and neoplastic cells are protected from autologous complement (C) attack by different cell-surface C-regulatory proteins including CD59 (protectin), CD46 (membrane cofactor protein) and CD55 (decay-accelerating factor). Indirect immunofluorescence (IIF) analysis showed a differential expression of CD59, CD46, and CD55 in nine human melanoma cell lines and that the expression of CD59 was highly heterogeneous compared with that of CD46 and CD55. Levels of cell membrane CD59 were found to regulate the differential sensitivity of melanoma cells investigated to homologous C-mediated lysis; in fact, an inverse correlation (r > 0.7, p < 0.05) was found between levels of cell membrane CD59, but not of CD46 and CD55, and extent of C-mediated lysis of melanoma cells sensitized with scalar concentrations of the anti-GD3 ganglioside mAb R24. Masking of CD59 by 2.5 micrograms/ml of the anti-CD59 mAb YTH53.1 induced or enhanced C-mediated lysis of melanoma cells sensitized with 2.5 micrograms/ml of mAb R24; the latter phenomenon was found to be directly correlated (r > 0.865, p < 0.01) with levels of cell membrane CD59. CD59 is bound to melanoma cells by a glycosylphosphatidylinositol anchor: treatment of C-resistant melanoma cells Mel 97, by increasing doses of phosphatidylinositol-specific phospholipase C (PI-PLC), progressively decreased cell-surface expression of CD59 and increased C-mediated lysis of cells sensitized with mAb R24. Staining of 38 benign and malignant lesions of melanocytic origin by mAb YTH53.1 demonstrated that CD59 is consistently expressed in vivo and confirmed the heterogeneous expression detected in vitro. Our data, altogether, demonstrate that CD59 is the main restriction factor of C-mediated lysis of melanoma cells and that levels of CD59 may account for their differential resistance to C-mediated lysis. The analysis of the levels of CD59 could represent an useful strategy in selecting melanoma patients who may benefit from immunotherapeutic treatment(s) that trigger C activation.

Anti-tyrosinase antibodies participate in the immune response to vaccination with anti-idiotypic antibodies mimicking the high-molecular-weight melanoma-associated antigen

Seven patients with metastatic melanoma were vaccinated with anti-idiotypic monoclonal antibody (mAb) MK2-23 which mimics the high-molecular-weight melanoma-associated antigen (HMW MAA). Sera samples were assayed for anti-anti-idiotypic antibodies, by Ab1-Ab2 complex inhibition test, for anti-B16 epitope antibodies, which are a heterogeneous group against various antigens presented on B16 melanoma cells and for anti-tyrosinase antibodies, which are specific against tyrosinase. Our results pointed to the participation of anti-tyrosinase antibodies in the immune response to vaccination by anti-idiotypic antibodies mimicking the HMW MAA. The anti-tyrosinase antibody kinetic curves presented an initial increase in titres in five cases followed by decreasing titres; in two cases a constant decrease was noted. The inhibition assay demonstrated an increasing percentage of inhibition (range 17-100%) within 100-400 days of treatment. The titre of the anti-tyrosinase antibodies increased following the vaccination, then decreased--probably due to absorption of the antibodies to melanoma cells and normal melanocytes. A positive slope in the percentage of inhibition was roughly associated with a negative slope of anti-tyrosinase antibodies. In one case, a long-standing complete clinical response was accompanied by development of melanoma-associated hypopigmentation. Anti-B16 epitope antibodies had no role in the response to vaccination. The development of anti-tyrosinase antibodies in response to vaccination by anti-idiotypic antibodies mimicking another antigen may be explained by induction of non-specific polyclonal B lymphocytes activation, a well-recognized phenomenon in autoimmune disorders.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of protectin (CD59) in human melanoma and its functional role in cell- and complement-mediated cytotoxicity

Immunohistochemical and/or indirect immunofluorescence analysis with monoclonal antibody (MAb) H19 demonstrated the expression of protectin (CD59) in 54 surgically removed metastatic melanoma lesions and on 8 out of 12 melanoma cell lines. CD59 expression had a low degree of intra- and intertumor heterogeneity. SDS-PAGE analysis showed that the molecular weight of CD59 expressed on melanoma cells is about 20 kDa. Treatment of melanoma cells with 5U/ml of phosphatidylinositol-specific phospholipase C completely abolished cell-surface expression of CD59. Interferon-gamma and/or tumor necrosis factor-alpha or phorbol 12-myristate 13-acetate neither modulated the expression of CD59 by melanoma cells nor influenced the amounts of CD59-specific mRNA. F(ab')2 fragments of anti-CD59 MAb YTH53. I did not inhibit the lysis of melanoma cells by allogeneic natural killer (NK) cells or lymphokine-activated killer (LAK) cells. In contrast, the whole Ig molecule of MAb HI9 or YTH53.I significantly (p < 0.05) enhanced NK-cell-mediated lysis of melanoma cells, suggesting the induction of antibody-dependent cell-mediated cytotoxicity. Lastly, masking of CD59 by MAb YTH53.I or its F(ab')2 fragments significantly (p < 0.05) enhanced, in a dose-dependent fashion, the lysis of anti-GD3-sensitized melanoma cells by homologous complement. These data demonstrate that CD59 expressed by human melanoma cells might regulate host-tumor interaction by protecting neoplastic cells from complement-mediated lysis.

Acute traumatic posterior fossa subdural haematomas

Acute Posterior Fossa Subdural Haematoma (PFSDH) caused by trauma is a clinical rarity: only 13 cases have been encountered in the literature. Three consecutive personal cases of PFSDH are presented. Two of them are respectively the sixth and the seventh surgically treated cases with success. Among the 16 cases 60% had a sudden clinical worsening within 24 hours. Seven cases had an occipital fracture. Of the thirteen cases operated upon 11 (85%) were in a state of deep coma. The surgical mortality was 46%. One patient had a good recovery (Grade 5) and six a moderate disability (Grade 4) on the Glasgow Outcome Scale. We conclude that surgical treatment must always be carried out even in patients presenting in an agonal state.

Typical interhemispheric subdural haematomas and falx syndrome: four cases and a review of the literature

Typical Interhemispheric Subdural Haematomas (ISDHs) are located along the whole interhemispheric fissure. In the four cases of our series, three of which surgically treated, and in the 29 cases reported in literature ISDH has been usually encountered in elderly age (mean age 56) in most of cases following head injury. Anticoagulant therapy was a favouring factor. The source of bleeding was never demonstrated at surgery, nevertheless some authors report a parafalcic bridging-veins laceration due to a brain linear acceleration during trauma, as cause. Clinically, immediate loss of consciousness was usually absent. Focal symptoms arose within 8-48 hours after trauma. In the majority of cases with ISDH, focal symptoms have been characterized by controlateral motor palsy with crural dominance as it has been observed in the "falx syndrome". Facial palsy was absent in all cases but one. Skull fractures were rare. On CT scan ISDH was shown as a spontaneously high density parafalcic area in a flat-convex lenticular shape. In the only case studied with MRI, the site where the ISDH emerged at brain convexity from the interhemispheric fissure, has been clearly localized by means of multiplanarity reconstructions, allowed us a target surgical approach. The majority of patients underwent surgery. The overall mortality rate was 24%: 14% among the 7 cases conservatively treated and 27% among the 26 operated ones. These last patients had a good recovery in 58% and an improvement in 15%. Surgical treatment must be promt as much as possible because of the possible sudden worsening of patient clinical conditions. Craniotomy is the surgical treatment that achieved the best results, nevertheless in our opinion the additional data offered by MRI may repropose the use of target cranial burr holes.

Cross-linking of HLA class II antigens modulates the release of tumor necrosis factor-alpha by the EBV-B lymphoblastoid cell line JY

In addition to their functional role as peptide-binding proteins HLA class II Ag can also act as signal-transducing molecules. The present study showed that cross-linking of HLA class II Ag by the anti-HLA-DR mAb L243 or by the anti-HLA-DR,-DP mAb IVA12 significantly (p &lt; 0.05) increased the release of TNF-alpha by the EBV-B lymphoblastoid cell line JY. In contrast, the anti-HLA-DR mAb 2.06 or the superantigens staphylococcal exotoxin toxic shock syndrome toxin-1 and staphylococcal enterotoxin B that bind to HLA-DR,-DQ Ag did not affect the release of TNF-alpha by JY cells. The accumulation of TNF-alpha in the culture medium of JY cells peaked at 24 h, decreased thereafter, and was found to be dependent on the dose of mAb L243 or mAb IVA12 used to cross-link HLA class II Ag. mAb L243 or staphylococcal exotoxin toxic shock syndrome toxin-1 enhanced the spontaneous homotypic aggregation of JY cells and mediated a dose-dependent inhibition of JY cell proliferation. These phenomena were not mediated by TNF-alpha released in response to cross-linking of HLA class II Ag; polyclonal anti-TNF-alpha neutralizing antibody did not affect JY cell aggregation and the inhibition of JY cell proliferation mediated by mAb L243. In contrast, TNF-alpha secreted by JY cells enhanced a nuclear factor-kB-like activity through the binding to the 75-kDa TNF-alpha receptor. These results demonstrate an additional role of HLA class II Ag as signal-transducing molecules regulating the production of bioactive TNF-alpha by EBV-B cells. The release of TNF-alpha after the triggering of HLA class II molecules could be relevant to different aspects of B cell biology and might play a role in the pathogenesis of human diseases in which antibodies cross-reactive to HLA class II Ag have been identified.

Cross-linking of HLA class II antigens modulates the release of tumor necrosis factor-alpha by the EBV-B lymphoblastoid cell line JY

In addition to their functional role as peptide-binding proteins HLA class II Ag can also act as signal-transducing molecules. The present study showed that cross-linking of HLA class II Ag by the anti-HLA-DR mAb L243 or by the anti-HLA-DR,-DP mAb IVA12 significantly (p < 0.05) increased the release of TNF-alpha by the EBV-B lymphoblastoid cell line JY. In contrast, the anti-HLA-DR mAb 2.06 or the superantigens staphylococcal exotoxin toxic shock syndrome toxin-1 and staphylococcal enterotoxin B that bind to HLA-DR,-DQ Ag did not affect the release of TNF-alpha by JY cells. The accumulation of TNF-alpha in the culture medium of JY cells peaked at 24 h, decreased thereafter, and was found to be dependent on the dose of mAb L243 or mAb IVA12 used to cross-link HLA class II Ag. mAb L243 or staphylococcal exotoxin toxic shock syndrome toxin-1 enhanced the spontaneous homotypic aggregation of JY cells and mediated a dose-dependent inhibition of JY cell proliferation. These phenomena were not mediated by TNF-alpha released in response to cross-linking of HLA class II Ag; polyclonal anti-TNF-alpha neutralizing antibody did not affect JY cell aggregation and the inhibition of JY cell proliferation mediated by mAb L243. In contrast, TNF-alpha secreted by JY cells enhanced a nuclear factor-kB-like activity through the binding to the 75-kDa TNF-alpha receptor. These results demonstrate an additional role of HLA class II Ag as signal-transducing molecules regulating the production of bioactive TNF-alpha by EBV-B cells. The release of TNF-alpha after the triggering of HLA class II molecules could be relevant to different aspects of B cell biology and might play a role in the pathogenesis of human diseases in which antibodies cross-reactive to HLA class II Ag have been identified.

Pure subdural haematomas of arteriolar origin

Fifteen consecutive cases of subdural haematomas (SDHs) of arteriolar origin operated on during the last twenty years in the Neurosurgical Clinic of the University of Genoa are reported. These SDHs are rare and form as a result of a rupture of a cortical arteriolar branch typically on the vicinity of the Sylvian fissure. They are always in a pure form and never associated with parenchymal lesions. Their aetiology is spontaneous, as in the 40% of our series, or more frequently related to minor traumas. These SDHs are often encountered in elderly patients generally presenting with severe clinical conditions (in the 60% of our patients GCS on admission was < 8). Prompt surgical treatment is required in all cases before further worsening of their neurological condition, even if CT scanning does not reveal parenchymal lesions. The mortality rate is over 50% and mainly relates to the pre-operative GC score. Clinical features, neuroradiological aspects and treatment are discussed and literature reviewed.

Differential expression of cell adhesion molecules CD54/CD11a and CD58/CD2 by human melanoma cells and functional role in their interaction with cytotoxic cells

Immunohistochemical staining with monoclonal antibodies showed a differential distribution of intercellular adhesion molecule 1 (ICAM-1/CD54) and lymphocyte function-associated antigen 3 (LFA-3/CD58) and their respective counterreceptors lymphocyte function-associated antigens 1 (LFA-1/CD11a) and 2 (LFA-2/CD2) on ten melanoma cell lines and in 46 surgically removed metastatic melanoma lesions. CD11a and CD2 were not detected on melanoma cells while CD54 and CD58 were coexpressed on the majority of the melanoma cell populations investigated. CD54 showed a higher degree of intra- and intertumor heterogeneity than CD58. gamma-Interferon and/or tumor necrosis factor alpha upregulated the expression of CD54 by melanoma cells, but neither modulated that of CD58 nor induced that of CD11a and CD2. Anti-CD54 and anti-CD58 monoclonal antibodies partially inhibited the lysis of melanoma cells by allogeneic natural killer cells, lymphokine-activated killer cells and, to a greater extent, by autologous tumor-infiltrating lymphocytes. Soluble CD54 (cCD54) purified from serum of patients with melanoma inhibited the lysis of melanoma cells F0-1 by natural killer cells in a dose-dependent fashion. These results suggest that membrane-bound CD54 and CD58 and cCD54 play a role in host-tumor interactions in patients with malignant melanoma and may account for the relationship between CD54 expression in primary lesions and the clinical course of disease.

Giant fusiform aneurysm in middle cerebral artery branches: a report of two cases and a review of the literature

Giant fusiform aneurysm (2.5 cm in length or more) is an unusual pathological entity typically described involving the main trunks of cerebral arteries and, rarely, cerebral artery branches. We are presenting two cases of middle cerebral artery branch giant fusiform aneurysm, one surgically and the other conservatively treated. We were unable to find in the literature reports of similar aneurysms at the same location. Clinical and pathological aspects, radiological findings, and treatment are discussed.

Traumatic posterior fossa extradural hematomas

17 cases of operated Posterior Fossa Epidural Hematomas (PFEDH) of traumatic origin are reported. Clinical and neuroradiological findings are presented and discussed. Authors emphasize the importance of CT scan in determining a more precise diagnosis and the related improvement in the morbidity (13%) and mortality (12%) rates.

Reduction in susceptibility to natural killer cell-mediated lysis of human FO-1 melanoma cells after induction of HLA class I antigen expression by transfection with B2m gene

Induction of HLA class I antigens on cultured melanoma cells FO-1 after transfection with a human or a mouse B2m gene was associated with a statistically significant reduction in their susceptibility to natural killer (NK) cell-mediated lysis. These results indicate that the structural differences between human and mouse beta 2-mu do not abolish the ability of the HLA class I molecular complex to modulate NK cell-mediated lysis of melanoma cells FO-1. The role of HLA class I antigens in the phenomenon is corroborated by the ability of anti-HLA class I MAb to enhance, although to a different extent, the susceptibility of transfected FO-1 cells to NK cell-mediated lysis. Gamma interferon (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) significantly reduced the susceptibility to NK cell-mediated lysis of transfected FO-1 cells. Surprisingly, TNF-alpha reduced the extent of lysis more than IFN-gamma, although the latter cytokine enhanced HLA class I antigen expression more than the former one. This finding, in conjunction with a reduction in the susceptibility to NK cell-mediated lysis of untransfected FO-1 cells incubated with IFN-gamma or TNF-alpha, suggests that the two cytokines reduce NK cell-mediated lysis of transfected cells by modulating not only the expression of HLA class I antigens, but also that of other structures. Induction of HLA class I antigens and their modulation with IFN-gamma did not affect the susceptibility to lymphokine-activated killer (LAK) cell-mediated lysis of transfected FO-1 cells. Characterization of the molecular mechanism(s) underlying abnormalities in HLA class I antigen expression by melanoma cells and of the role of these molecules in the interactions of melanoma cells with various types of effector cells may suggest novel immunotherapeutic approaches to melanoma.

Glomerular dynamics and salt balance in pregnant rats with renal hypertension

These studies were aimed at investigating whether chronic hypertension in pregnancy causes changes both in salt excretion (NaE) and in glomerular hemodynamics. Metabolic and renal micropuncture studies were performed in pregnant (P) and Virgin (V) Munich-Wistar rats with normal blood pressure (N) and two-kidney Goldblatt hypertension (H). Mean NaE was higher in PN than VN (2.7 vs. 1.7 meq/day, P less than 0.01). Hypertension raised NaE both in P and V rats: in P and V rats with "benign" hypertension (blood pressure less than 180 mmHg) NaE averaged 3.2 and 2.6 meq/day, respectively (P less than 0.05); mean NaE was 5.9 and 3.8 meq/day, respectively (P less than 0.01), in P and V rats with "malignant" hypertension (blood pressure greater than or equal to 180 mmHg). Afferent arteriole resistance (Ra) averaged 1.73 and 3.50 10 dyn.s-1.cm5 in PN and VN, respectively (P less than 0.01). Hypertension raised Ra in V, but not in P rats (4.47 vs. 2.14 10 dyn.s-1.cm5, P less than 0.01). Thus glomerular plasma flow, glomerular capillary hydrostatic pressure, and single-nephron glomerular filtration rate were markedly higher in PH than VH rats: in PH rats single-nephron filtration fraction was significantly lower than in VH. These results show that in PH rats a marked rise in NaE is associated with glomerular vasodilation.

Reversibility of acute cyclosporin nephrotoxicity by dopamine. Micropuncture study in the rat

The ability of dopamine to neutralise the effects acutely induced by cyclosporin (CsA) on glomerular dynamics was evaluated in four groups of female Munich-Wistar rats, prepared for micropuncture: group I (n = 9), normal rats receiving saline as placebo; group II (n = 10), rats treated with CsA (20 mg/kg b.w. in 1 h); group III (n = 8) rats treated with CsA, as in group II, and then with vasodilating doses of dopamine (1.2-2.0 micrograms/100 g b.w./min in continuous intravenous infusion); group IV (n = 7), rats administered Cremophore EL, the vehicle of CsA, in corresponding doses. Single nephron GFR (SNGFR), glomerular plasma flow (GPF), afferent and efferent arteriole resistances (Ra and Re, respectively), SN filtration fraction (SNFF), ultrafiltration coefficient (Kf) were measured. Body weight, blood pressure and haematocrit were similar in the four groups. GFR was significantly reduced in group II (0.83 +/- 0.08 ml/min vs 1.29 +/- 0.01 in group I, 1.46 +/- 0.25 in group III, and 1.40 +/- 0.09 in group IV, P less than 0.05 vs all the groups), while no statistical difference was detected in urinary volume. SNGFR was significantly reduced in group II vs group I (18.7 +/- 1.8 nl/min vs 30.6 +/- 1.3, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute traumatic vertex epidural haematomas surgically treated

Eleven consecutive cases of acute traumatic vertex epidural haematomas (VEDHs) among 416 epidural haematomas (EDHs) operated on during the same period in the Neurosurgical Clinic of the University of Genoa, are reported. Clinical features, neuroradiological aspects (X-ray, angiography and CT scan) and results are discussed, in order to point out the problems encountered in the diagnosis, expecially due to the mystifying clinical picture and the unsuitability of the axial CT scan in the detection of these lesions. In this series mortality rate was 18%, against 50% reported in the literature.