Galectins and Gliomas

Malignant gliomas, especially glioblastomas, are associated with a dismal prognosis. Despite advances in diagnosis and treatment, glioblastoma patients still have a median survival expectancy of only 14 months. This poor prognosis can be at least partly explained by the fact that glioma cells diffusely infiltrate the brain parenchyma and exhibit decreased levels of apoptosis, and thus resistance to cytotoxic drugs. Galectins are a family of mammalian beta-galactoside-binding proteins characterized by a shared characteristic amino acid sequence. They are expressed differentially in normal vs. neoplastic tissues and are known to play important roles in several biological processes such as cell proliferation, death and migration. This review focuses on the role played by galectins, especially galectin-1 and galectin-3, in glioma biology. The involvement of these galectins in different steps of glioma malignant progression such as migration, angiogenesis or chemoresistance makes them potentially good targets for the development of new drugs to combat these malignant tumors

Multicentre phase II studies evaluating imatinib plus hydroxyurea in patients with progressive glioblastoma

Contains fulltext : 79699.pdf (publisher's version ) (Closed access)BACKGROUND: We evaluated the efficacy of imatinib mesylate in addition to hydroxyurea in patients with recurrent glioblastoma (GBM) who were either on or not on enzyme-inducing anti-epileptic drugs (EIAEDs). METHODS: A total of 231 patients with GBM at first recurrence from 21 institutions in 10 countries were enrolled. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 600 mg per day for patients not on EIAEDs and at 500 mg twice a day if on EIAEDs. The primary end point was radiographic response rate and secondary end points were safety, progression-free survival at 6 months (PFS-6), and overall survival (OS). RESULTS: The radiographic response rate after centralised review was 3.4%. Progression-free survival at 6 months and median OS were 10.6% and 26.0 weeks, respectively. Outcome did not appear to differ based on EIAED status. The most common grade 3 or greater adverse events were fatigue (7%), neutropaenia (7%), and thrombocytopaenia (7%). CONCLUSIONS: Imatinib in addition to hydroxyurea was well tolerated among patients with recurrent GBM but did not show clinically meaningful anti-tumour activity

Vaccination anti-tumorale: État actuel des connaissances

SCOPUS: cp.jinfo:eu-repo/semantics/publishe

Approches thérapeutiques innovantes dans le mélanome

SCOPUS: re.jinfo:eu-repo/semantics/publishe

Therapeutic efficacy of antitumor dendritic cell vaccinations correlates with persistent Th1 responses, high intratumor CD8+ T cell recruitment and low relative regulatory T cell infiltration.

Despite the increasing number of immunotherapeutic strategies for the treatment of cancer, most approaches have failed to correlate the induction of an anti-tumor immune response with therapeutic efficacy. We therefore took advantage of a successful vaccination strategy-combining dendritic cells and irradiated GM-CSF secreting tumor cells-to compare the immune response induced against 9L gliosarcoma tumors in cured rats versus those with progressively growing tumors. At the systemic level, the tumor specific cytotoxic responses were quite heterogeneous in uncured vaccinated rats, and were surprisingly often high in animals with rapidly-growing tumors. IFN-gamma secretion by activated splenic T cells was more discriminative as the CD4+ T cell-mediated production was weak in uncured rats whereas high in cured ones. At the tumor level, regressing tumors were strongly infiltrated by CD8+ T cells, which demonstrated lytic capacities as high as their splenic counterparts. In contrast, progressing tumors were weakly infiltrated by T cells showing impaired cytotoxic activities. Proportionately to the T cell infiltrate, the expression of Foxp3 was increased in progressive tumors suggesting inhibition by regulatory T cells. In conclusion, the main difference between cured and uncured vaccinated animals does not depend directly upon the induction of systemic cytotoxic responses. Rather the persistence of higher CD4+ Th1 responses, a high intratumoral recruitment of functional CD8+ T cells, and a low proportion of regulatory T cells correlate with tumor rejection.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

In vitro and in vivo pharmacological characterizations of the antitumor properties of two new olivacine derivatives, S16020-2 and S30972-1.

S16020-2, a new olivacine derivative and a topoisomerase II inhibitor, has recently entered clinical trials. New analogues and derivatives have been synthesized from the S16020-2 compound. Preliminary data indicate that S30972-1, one of these S16020-2 derivatives, may exhibit a comparatively higher level of antitumor potency associated with an improved therapeutic index than does S16020-2. The antitumor activities of S16020-2 and S30972-1 were therefore characterized both in vitro and in vivo, with Adriamycin and etoposide chosen as reference compounds. The in vitro data show that S30972-1 is a topoisomerase II inhibitor, mediating its activity through an ATP-dependent mechanism such as S16020-2. The two olivacine derivatives exhibited similar activities in vitro at the levels of the global growth of six human cancer cell lines, of the induction of apoptosis, and of the G2 cell cycle phase arrest. The in vivo antitumor activity characterization included the use of two murine leukemia types (P388-LEU and L1210-LEU), two murine lymphoma-like models (P388-LYM and L1210-LYM), two mammary adenocarcinomas (MXT-HI and MXT-HS), and one melanoma (B16). The data show that S30972-1 is actually more efficient in vivo than S16020-2, a feature that may relate to the fact that S30972-1 is less toxic than S16020-2. The S30972-1 compound exhibited in vivo a level of antitumor activity that was also actually higher than that exhibited by Adriamycin and similar to that exhibited by etoposide.Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe