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G Finocchiaro

Publications and source records attributed to G Finocchiaro.

At least 37 records · Page 2Linked to original sources
PubMed2000

Identification of regulatory regions of the putative tumor suppressor gene DMBT1.

The lack of expression of the putative tumor suppressor gene DMBT1 has been described in gliomas, lung carcinomas, and other malignancies. To investigate the mechanisms regulating DMBT1 expression we have screened a human genomic library with a 5' cDNA probe and identified a fragment of approximately 3 kb upstream of the proposed coding sequence of DMBT1. This fragment contains subregions that may up- or down-regulate the expression of a reporter gene. These findings may help to elucidate the mechanisms regulating the alternative splicing and the tissue specific expression of DMBT1.

Agglutinins↗
PubMed2000

Gene therapy of experimental brain tumors using neural progenitor cells.

Glioblastomas, the most frequent and malignant of primary brain tumors, have a very poor prognosis. Gene therapy of glioblastomas is limited by the short survival of viral vectors and by their difficulty in reaching glioblastoma cells infiltrating the brain parenchyma. Neural stem/progenitor cells can be engineered to produce therapeutic molecules and have the potential to overcome these limitations because they may travel along the white matter, like neoplastic cells, and engraft stably into the brain. Retrovirus-mediated transfer of the gene for interleukin-4 is an effective treatment for rat brain glioblastomas. Here, we transferred the gene for interleukin-4 into C57BL6J mouse primary neural progenitor cells and injected those cells into established syngeneic brain glioblastomas. This led to the survival of most tumor-bearing mice. We obtained similar results by implanting immortalized neural progenitor cells derived from Sprague-Dawley rats into C6 glioblastomas. We also documented by magnetic resonance imaging the progressive disappearance of large tumors, and detected 5-bromodeoxyuridine-labeled progenitor cells several weeks after the injection. These findings support a new approach for gene therapy of brain tumors, based on the grafting of neural stem cells producing therapeutic molecules.

Animals↗
PubMed2000

Paracrine delivery of IL-12 against intracranial 9L gliosarcoma in rats.

OBJECT: Interleukin-12 (IL- 12) has potential for the treatment of tumors because it can stimulate an antitumor immune response and possesses antiangiogenic properties. In the study reported here, the authors investigated the therapeutic role of locally delivered IL-12 in a malignant brain tumor model. METHODS: After genetically engineering 9L gliosarcoma cells to express IL-12 (9L-IL12 cells), the authors used these cells as a source of locally delivered cytokine. First, they investigated the behavior of these cells, which were implanted with the aid of stereotactic guidance into the rat brain, by using serial magnetic resonance imaging and histopathological examination. Second, they assessed the antitumor efficacy of proliferating, as well as nonproliferating (irradiated), 9L-IL12 cells by implanting these cells in animals challenged by wild-type 9L gliosarcoma (9Lwt) cells. The IL-12 expression in brain regions injected with 9L-IL12 was confirmed by reverse transcription-polymerase chain reaction. Last, the authors explored whether animals treated with 9L-IL12 cells developed an antitumor immunological memory by rechallenging the survivors with a second injection of 9Lwt cells. The authors demonstrated that local delivery of IL-12 into the rat brain by genetically engineered cells significantly prolongs survival time in animals challenged intracranially with a malignant glioma. CONCLUSIONS: These findings support continued efforts to refine local delivery systems of IL-12 in an attempt to bring this therapy to clinical trials.

Animals↗
PubMed2000

MR imaging and proton MR spectroscopy in adult Krabbe disease.

We present the MR imaging findings in four patients (two pairs of siblings from two unrelated families) with adult Krabbe disease. In the first family, clinical presentation mimicked familial spastic paraplegia. Their MR images showed selective, increased signal intensity on T2-weighted sequences along the corticospinal tracts, most prominently in the proband and barely detectable in her brother. Proton MR spectroscopy showed increased choline and myo-inositol in the affected white matter. In the second family, the clinical presentation differed in that the signs of pyramidal tract involvement were asymmetrical, with concomitant asymmetry on MR images in one. In adults, Krabbe disease may present on MR imaging with selective pyramidal fiber involvement.

Adult↗
PubMed1999

Identification of PTEN-related sequences in glioma cells and in non-neoplastic cell lines.

The PTEN gene, which encodes a tumor suppressor with phosphatase activity, is located on chromosome 10q23 and is mutated in different tumors, including glioblastomas (GBM). We found evidence for a PTEN-related sequence (PTEN-rs) on genomic DNA of GBM and non-neoplastic cells. PTEN-rs does not contain introns and presents several conserved missense mutations, including a T to G transversion at the initiation codon. Rsa I digestion may help to identify this putative PTEN pseudogene which, according to RT-PCR analysis on glioma, fibroblast, brain and lung cells, does not appear to be transcribed.

Fibroblasts↗
PubMed1999

A recurrent 19q11-12 breakpoint suggested by cytogenetic and fluorescence in situ hybridization analysis of three glioblastoma cell lines.

Loss of genetic material at chromosome 19 is a rather frequent finding in malignant gliomas. Loss of heterozygosity at region 19q13.3 is common in oligodendrogliomas and is also present, together with other genetic alterations on the same chromosome, in glioblastoma multiforme (GBM). Here we describe the results of cytogenetic and fluorescence in situ hybridization analysis on three GBM cell lines in which a series of complex chromosomal rearrangements affecting chromosome 19 were present. These genetic alterations suggest the presence of a common breakpoint at 19q11-12 which may point to the localization of a fragile site and/or to the presence of tumor suppressor gene(s) in the pericentromeric region of chromosome 19.

Brain Neoplasms↗
PubMed1999

Eradication of rat malignant gliomas by retroviral-mediated, in vivo delivery of the interleukin 4 gene.

Overexpression of interleukin 4 (IL-4) can impair the tumorigenicity of glioma cells, but direct evidence of its antitumor efficacy after in vivo gene transfer into malignant gliomas has not been provided. To test this, we first injected into the brain of Sprague Dawley rats a 1:1 mixture of C6 rat glioblastoma cells and psi2.L4SN20 or E86.L4SN50 retroviral producer cells (RPCs), secreting 20 and 50 ng of IL-4/5 x 10(5) cells/48 h, respectively. Twenty-seven and 56% of rats receiving injections with these low- or medium-level IL-4 RPCs, respectively, survived tumor injection, whereas control rats died in about 1 month. E86.L4SN50 RPCs coinjected with 9L gliosarcoma cells into syngeneic Fischer 344 rats yielded similar results. A novel IL-4 RPC clone expressing higher levels of IL-4, E86.L4SN200, coinjected with 9L cells increased to 75% the fraction of long-term survivors and induced tumor regression in 50% of rats when injected into established 9L gliosarcomas. Cured rats developed an immunological memory because they rejected a challenge of wild-type 9L cells into the contralateral hemisphere. Magnetic resonance imaging was used to monitor 9L and C6 gliomas and gave direct evidence for tumor rejection in treated rats. Immunohistology showed inflammatory infiltrates in IL-4-treated tumors in which CD8+ T lymphocytes were more abundant, although CD4+ T lymphocytes, B lymphocytes, and macrophages were also present. Overall, these findings suggest that IL-4 gene transfer is a new, promising approach for treating malignant gliomas.

Animals↗
PubMed1999

Retrovirus-mediated IL-4 gene therapy in spontaneous adenocarcinomas from MMTV-neu transgenic mice.

Gene therapy approaches to the treatment of experimental cancer are usually based on established neoplastic cell lines which are manipulated in vitro and subsequently transplanted in host animals. However, the relevance of these artificial models to the biology and therapy of human tumors is uncertain. We have previously validated an experimental model based on MMTV-neu transgenic mice in which breast tumors arise spontaneously in 100% of animals and have many features in common with their human counterpart, including the involvement of the neu oncogene and the ability to metastatize. In this article we report the effect of intratumoral, retrovirus-mediated, IL-4 expression on the growth of breast tumors arising in these mice. The size of IL-4 inoculated tumors on the right side was significantly smaller than that of controlateral untreated tumors, suggesting a local effect of IL-4. In addition, the non-injected tumors on the left side of treated animals were significantly smaller than those arising in control transgenic mice, suggesting that IL-4 can also inhibit tumor growth systemically. These findings suggest that IL-4 gene transfer can significantly reduce the growth rate of spontaneously arising breast tumors and that immune-based gene therapy could efficiently complement other approaches based on different mechanisms, such as suicide gene transfer or antisense technology.

Animals↗
PubMed1998

Retroviral-mediated transfer of the galactocerebrosidase gene in neural progenitor cells.

Globoid cell leukodystrophy (GCL or Krabbe disease) is a recessive disease caused by mutations of the lysosomal enzyme galactocerebrosidase (GALC) and twitcher is the murine model of GCL. We have prepared retroviral packaging cell lines to transduce the GALC gene. Retroviral transduction restored GALC activity in GCL fibroblasts and increased such activity to very high levels in immortalized neural progenitor cells (ST14A cells). GALC activity was also normalized in twitcher fibroblasts co-cultured with ST14A cells over-expressing GALC, demonstrating that this enzyme is secreted and can be imported efficiently by GALC-deficient cells. These results give the necessary background to evaluate the therapeutic effect in twitcher of brain grafting of neural progenitor cells engineered to release high levels of GALC.

3T3 Cells↗
PubMed1998

PTEN/MMAC1 mutations in primary glioblastomas and short-term cultures of malignant gliomas.

A novel tumor suppressor, PTEN/MMAC1, was recently found on chromosome 10q23 and mutations of this gene were described in about 20% of primary glioblastomas (GBM) and 60% of GBM cell lines. To define further the relevance of PTEN/MMAC1 mutations in GBM we investigated by SSCP analysis its coding sequence in 44 gliomas, including 41 GBM, and in 21 short-term cultures (15 GBM and six malignant astrocytomas). Loss of heterozygosity (LOH) at 10q23 was present in at least one marker in the vicinity of the PTEN/MMAC1 locus in 59% of the informative GBM (primary tumors and cell cultures). SSCP variant bands were found in seven primary GBM (17%) and in one short-term GBM culture and sequence analysis confirmed the presence of somatic mutations in all these cases (five missense, one splicing mutation and two small deletions). These data indicate that PTEN/MMAC1 is inactivated in a subset of GBM and suggest that the high mutation frequency previously found in GBM established cell lines reflects culture condition artifacts rather than the true mutation frequency in vivo. Other suppressors, located on chromosome 10q, may also have a critical role in glioma tumorigenesis.

Astrocytoma↗
PubMed1998

In vitro and in vivo effects of retrovirus-mediated transfer of the connexin 43 gene in malignant gliomas: consequences for HSVtk/GCV anticancer gene therapy.

In tumors, gap junctional intercellular communication (GJIC) is usually down-regulated and the expression of connexins, membrane proteins constituting gap junction channels, is often low or altered. GJIC, allowing the intercellular diffusion of ganciclovir (GCV) triphosphate, is also one mediator of the 'bystander effect', the phenomenon by which herpes simplex virus thymidine kinase (HSVtk)-transduced, neoplastic cells kill surrounding HSVtk-negative cells when treated with GCV. We set up experiments to evaluate the effects of retrovirus-mediated in vivo gene transfer of connexin 43 in malignancies with low GJIC capacity. We found that U-87 human glioblastoma cells transfected in vitro by the human Cx43 cDNA grow significantly more slowly than control U-87 cells and lose their tumorigenicity when injected subcutaneously in nude mice. When the Cx43 gene was transduced in vitro in U-87 cells by a retroviral producer cell line (N3.2.ii, titer 1.5 x 10(6) c.f.u./ml) in vivo results were similar. However, only when U-87 cells were co-injected with N3.2.ii cells in nude mice in a 1:5 ratio, a 50% reduction in tumor size was obtained during the first 3 weeks. Moreover the coinjection of U-87 cells with N3.2.ii and SBA cells (a retroviral producer cell line expressing the HSVtk gene), was not able to potentiate the effects of GCV administration, suggesting that Cx43 gene transfer requires more efficient vectors to increase the bystander effect in vivo.

Animals↗
PubMed1997

Limited efficacy of the HSV-TK/GCV system for gene therapy of malignant gliomas and perspectives for the combined transduction of the interleukin-4 gene.

The growth of U-87 or C6 gliomas co-implanted in nude mice with retroviral producer cells (VPC) expressing the herpes simplex virus-thymidine kinase (HSV-tk) gene is only partially impaired by treatment with ganciclovir (GCV). The effect of GCV is even less evident when C6 and VPC are co-implanted into the rat brain. Furthermore, tumors from C6 cells carrying the HSV-tk gene are not eradicated by GCV, although they remain sensitive to GCV when replated in vitro. These limits of the HSV-tk/GCV system in glioma gene therapy may be due to insufficient gene transfer and/or insufficient delivery of GCV to glioma cells. Combination of HSV-tk and one or more cytokines may improve the antitumor efficacy. Among cytokines, interleukin-4 (IL-4) has already been shown to be active against gliomas. In nude mice, GCV treatment inhibited tumor growth more effectively after co-injection of C6 cells with a mixture of VPC transducing IL-4 and HSV-tk genes than after co-injection with either IL-4 or HSV-tk VPC only. In immunocompetent Sprague-Dawley rats, co-injection of IL-4 VPC and C6 cells was also effective in inhibiting the growth of C6 brain tumors, 38% of the animals surviving for at least 2 months. Furthermore, increased and prolonged antitumor efficacy was obtained by transducing both IL-4 and HSV-tk genes.

Animals↗
PubMed1997

Construction of a 5-Mb YAC contig from the putative 10q25 tumor-suppressor region for glioblastomas.

During the final step of the malignant progression to glioblastoma multiforme (GBM), the most frequent and malignant of primary brain tumors, more than 90% of the cases exhibit loss of genetic material on chromosome 10. We previously identified a 4-cM deletion interval in the 10q24-qter region that is common to all the GBM we have examined. A contig of 20 YACs spanning the 5 Mb of chromosomal DNA in the region has been assembled. Overlaps between YACs have been verified by STS content, fingerprinting analysis, and/or Alu-Alu PCR. The contig contains 17 known microsatellite markers, 15 new STSs derived from the insert ends of YACs, 9 ESTs, and 11 others STSs, for a total of 52 STSs (average marker density 1/100 kb). The physical map of this region will facilitate the search for a candidate tumor-suppressor gene(s) that is inactivated during the information of GBM.

Base Sequence↗
PubMed1997

Gene transfer of suicide genes for the treatment of malignant gliomas: efficacy, limitations, and perspectives for a combined immunotherapy.

The potential of gene therapy strategies for malignant gliomas that are based on retroviral-mediated transfer of a "suicide gene" such as Herpes Simplex Virus-thymidine kinase HSV-tk and subsequent treatment by a prodrug (ganciclovir, for example), has been emphasized by the promising results obtained by several groups. However, further experimental data as well as preliminary clinical results indicate that the low efficiency of retroviral-mediated gene transfer in vivo as well as difficulties for the diffusion of the prodrug inside the tumour mass can limit the efficacy of this form of gene therapy. To achieve a more effective limitation of tumour growth other approaches may be combined with the "suicide gene" strategy and the enhancement of the immunological response to the tumour by cytokine gene transfer is prominent among these approaches. The authors' experiments in nude mice confirm the antineoplastic role of IL-4 and encourage testing the effects of the simultaneous transfer of IL-4 and HSV-tk genes in immunocompetent animals.

Animals↗
PubMed1997

Perspectives for the gene therapy of malignant gliomas by suicide gene transfer.

A promising strategy in the treatment of malignant gliomas involves the creation of Herpes Simplex Virus-thymidine kinase (HSV-tk) modified tumor cells. Some authors have observed complete tumor regression after ganciclovir (GCV) treatment of established gliomas transduced in vivo by the HSV-tk gene. Yet, further investigations did not confirm completely these results, even if confirmed the therapeutic potential of such a therapy. Using the rat C6 glioblastoma as a model of malignant brain tumor, we investigated the efficacy of in vivo and in vitro transduction of growing brain tumors with the HSV-tk gene, followed by GCV administration. The stereotactic injection into the left striatum of C6 cells mixed with retroviral producer cells and GCV treatment did not improve significantly the animal survival compared to controls. On the contrary, there was a significant prolongation of the survival of rats inoculated with C6 cells engineered in vitro to express the HSV-tk gene. Nevertheless, complete eradication of the tumors was not achieved. We also injected a group of six rats with a mixture of cells expressing the murine Interleukin-4 (IL-4) gene and C6 cells. IL-4 has been shown to produce the regression of experimental brain tumors. Our preliminary experience seems to confirm that hypothesis. Our results indicate that the outcome of HSV-tk gene therapy can be limited not only by low gene transfer but also by insufficient delivery of GCV to tumor cells. Combined strategies, based on contemporary transduction of HSV-tk and IL-4, may enhance the therapeutic perspectives of such a therapy.

Animals↗
PubMed1997

Clinicopathological features of early gastric cancer in younger versus older patients in a high incidence area of northern Italy.

AIMS: The relationship between the clinicopathological features of early gastric cancer and age were analysed in a retrospective study of 168 patients. METHODS: 168 patients, residents of the Region of Cremona, who had undergone surgery in the period 1978 to 1990 for early gastric cancer, were divided into two groups by age and compared. Group I (n = 89) consisted of patients less than 65 years of age and Group II (n = 79) of patients between 66 and 85 years of age. RESULTS: There were no significant differences between the two groups with respect to the sex ratio, tumour size, depth of tumour invasion, and 5-year survival rate. Group I patients showed more lymph node involvement (p < 0.01), cancer of the diffuse histological type (p < 0.01), and cancers located in the gastric body (p < 0.05). Conversely, Group II exhibited more cancers of the protruded (p < 0.05) and intestinal histological type (p < 0.01), and more adenomatous residue (p < 0.01). CONCLUSIONS: Our findings suggest that early gastric cancer may present differently in different age groups; persons 65 years of age and older are more likely to have early gastric cancer of the slow-growing type than middle-aged patients.

Adult↗