GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • American Association for Cancer Research (AACR)  (5)
  • 1
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 64, No. 1 ( 2004-01-01), p. 378-385
    Abstract: Natural killer (NK) cells were first identified for their ability to kill tumor cells of different origin in vitro. Similarly, γδ T lymphocytes display strong cytotoxic activity against various tumor cell lines. However, the ability of both the NK and γδ cells to mediate natural immune response against human malignant tumors in vivo is still poorly defined. Severe combined immunodeficient (SCID) mice have been successfully engrafted with human tumors. In this study, the antitumor effect of local as well as of systemic treatments based on NK cells or Vδ1 or Vδ2 γ/δ T lymphocytes against autologous melanoma cells was investigated in vivo. The results show that all three of the populations were effective in preventing growth of autologous human melanomas when both tumor and lymphoid cells were s.c. inoculated at the same site. However, when lymphoid cells were infused i.v., only NK cells and Vδ1 γ/δ T lymphocytes could either prevent or inhibit the s.c. growth of autologous melanoma. Accordingly, both NK cells and Vδ1 γδ T lymphocytes could be detected at the s.c. tumor site. In contrast, Vδ2 γδ T lymphocytes were only detectable in the spleen of the SCID mice. Moreover, NK cells maintained their inhibitory effect on tumor growth even after discontinuation of the treatment. Indeed they were present at the tumor site for a longer period. These data support the possibility to exploit NK cells and Vδ1 γδ T lymphocytes in tumor immunotherapy. Moreover, our study emphasizes the usefulness of human tumor/SCID mouse models for preclinical evaluation of immunotherapy protocols against human tumors.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2004
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 75, No. 15_Supplement ( 2015-08-01), p. LB-119-LB-119
    Abstract: Background: We showed that standard dose TMZ (150 mg/mq/day day1-5q28) is tolerable and active in 32 heavily pre-treated patients with advanced CRC and MGMT promoter methylation (Pietrantonio et al., Ann Oncol 2014). In a subsequent study, we included 32 pts treated with dose-dense TMZ (75 mg/mq/day day 1-21q28, for up to 6 cycles or until progression/unacceptable toxicity). Additional predictive markers are needed for improved selection of patients for TMZ therapy in metastatic CRC. Retained MGMT expression by IHC was proposed as marker for negative selection of pts with brain tumors. We conducted a retrospective analysis to assess MGMT expression in our 2 studies and to correlate this with the outcomes. Methods: All 64 patients included in the 2 studies were defined as MGMT methylation-positive according to methylation-specific PCR. A total of 40 patients had tissue available for IHC. Expression of nuclear MGMT protein was defined scored semiquantitatively according to extension and intensity. Using ROC analysis, IHC score & lt;4 was considered as MGMT-low expression vs. IHC score 4-12 as MGMT-high. Extended RAS-BRAF mutations were assessed by Sanger sequencing. Results: Herein, we report for the first time the results of the dose-dense TMZ study. We obtained 4 confirmed partial responses and 2 stable disease, accounting for a response rate of 12% and a clinical benefit of 18%. Median PFS was 1.8 months. OS data are not mature. Thus, the results are comparable to those obtained in the previous study. MGMT-low expression was found in 15 (38%) samples and MGMT-high in 25 (62%). RAS-BRAF mutations were found in 28 (70%) pts and were not correlated with MGMT expression (p = 1). Response rate was significantly higher in patients with MGMT-low (53%) vs. those with MGMT-high (p & lt;0.0001). Progression-free survival was significantly longer in MGMT-low vs. MGMT-high(5 vs. 2.3 months; p = 0.001). Further analyses are ongoing to validate MGMT IHC as a biomarker and to correlate it with quantitative gene methylation analysis. Conclusions: In this translational study on MGMT methylated CRC, absence of MGMT expression was significantly correlated with tumor response and benefit from TMZ treatment. Citation Format: Filippo De Braud, Filippo Pietrantonio, Maria Di Bartolomeo, Katia Fiorella Dotti, Claudia Maggi, Roberto Iacovelli, Marta Caporale, Rosa Berenato, Federica Perrone, Elena Tamborini, Alessio Pellegrinelli, Stefano Federici, Fabrizio Festinese, Giuseppe Pelosi, Ilaria Bossi, Paola Valentina Consonni, Susanna Maggi, Massimo Milione. MGMT immunohistochemistry (IHC) improves patients’ selection for temozolomide (TMZ) treatment in advanced chemorefractory MGMT-methylated colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-119. doi:10.1158/1538-7445.AM2015-LB-119
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2015
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 66, No. 7 ( 2006-04-01), p. 3629-3638
    Abstract: The phenomenon of cell cannibalism, which generally refers to the engulfment of cells within other cells, was described in malignant tumors, but its biological significance is still largely unknown. In the present study, we investigated the occurrence, the in vivo relevance, and the underlying mechanisms of cannibalism in human melanoma. As first evidence, we observed that tumor cannibalism was clearly detectable in vivo in metastatic lesions of melanoma and often involved T cells, which could be found in a degraded state within tumor cells. Then, in vitro experiments confirmed that cannibalism of T cells was a property of metastatic melanoma cells but not of primary melanoma cells. In particular, morphologic analyses, including time-lapse cinematography and electron microscopy, revealed a sequence of events, in which metastatic melanoma cells were able to engulf and digest live autologous melanoma-specific CD8+ T cells. Importantly, this cannibalistic activity significantly increased metastatic melanoma cell survival, particularly under starvation condition, supporting the evidence that tumor cells may use the eating of live lymphocytes as a way to “feed” in condition of low nutrient supply. The mechanism underlying cannibalism involved a complex framework, including lysosomal protease cathepsin B activity, caveolae formation, and ezrin cytoskeleton integrity and function. In conclusion, our study shows that human metastatic melanoma cells may eat live T cells, which are instead programmed to kill them, suggesting a novel mechanism of tumor immune escape. Moreover, our data suggest that cannibalism may represent a sort of “feeding” activity aimed at sustaining survival and progression of malignant tumor cells in an unfavorable microenvironment. (Cancer Res 2006; 66(7): 3629-38)
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2006
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 67, No. 11 ( 2007-06-01), p. 5408-5417
    Abstract: Proton pumps like the vacuolar-type H+ ATPase (V-ATPase) are involved in the control of cellular pH in normal and tumor cells. Treatment with proton pump inhibitors (PPI) induces sensitization of cancer cells to chemotherapeutics via modifications of cellular pH gradients. It is also known that low pH is the most suitable condition for a full PPI activation. Here, we tested whether PPI treatment in unbuffered culture conditions could affect survival and proliferation of human B-cell tumors. First, we showed that PPI treatment increased the sensitivity to vinblastine of a pre-B acute lymphoblastic leukemia (ALL) cell line. PPI, per se, induced a dose-dependent inhibition of proliferation of tumor B cells, which was associated with a dose- and time-dependent apoptotic-like cytotoxicity in B-cell lines and leukemic cells from patients with pre-B ALL. The effect of PPI was mediated by a very early production of reactive oxygen species (ROS), that preceded alkalinization of lysosomal pH, lysosomal membrane permeabilization, and cytosol acidification, suggesting an early destabilization of the acidic vesicular compartment. Lysosomal alterations were followed by mitochondrial membrane depolarization, release of cytochrome c, chromatin condensation, and caspase activation. However, inhibition of caspase activity did not affect PPI-induced cell death, whereas specific inhibition of ROS by an antioxidant (N-acetylcysteine) significantly delayed cell death and protected both lysosomal and mitochondrial membranes. The proapoptotic activity of PPI was consistent with a clear inhibition of tumor growth following PPI treatment of B-cell lymphoma in severe combined immunodeficient mice. This study further supports the importance of acidity and pH gradients in tumor cell homeostasis and suggests new therapeutic approaches for human B-cell tumors based on PPI. [Cancer Res 2007;67(11):5408–17]
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2007
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 78, No. 13_Supplement ( 2018-07-01), p. 3613-3613
    Abstract: Functional profiling is an emerging trend in precision medicine. Manual laboratory methods proved to be effective in predicting the response to drug treatments both in patients stratified according to genetic profiling and in patients without any specific molecular aberration. In this work, we validated the predictive power of an innovative functional profiling platform, based on lab-on-a-chip technology, which allows testing the response of live tumor cells exposed to anticancer drugs in a fully-automated process, requiring only a Ficoll stratification as a manual step. 15 AML patients (Age: 40% & lt;60 years, 46% in the 60-70 years range, 14% & gt;70 years; Gender: 40% Female; ELN Classification: 20% Favorable, 26% Intermediate-I, 33% Intermediate-II, 14% Adverse; AML stage: 53% De novo, 7% Relapse, 40% Refractory; Treatment: 20% FLAI-3, 40% FLAI-5, 26% Decitabine; 7% Cytarabine, 7% 5-azacitidine) were treated at the Policlinico Sant'Orsola in Bologna. At the same time, bone marrow samples were challenged with the same drugs at scaled concentrations in the functional profiling platform developed by CellPly and an output score was extracted from time-lapse fluorescence image analysis of patient tumor cells exposed to the drug or drug combination for 24 hours. Clinical follow up resulted in the following classification: complete hematologic response (CR) was found in 6/15 patients (6/6 with a De Novo disease), while the remaining 9/15 patients (2/9 de novo; 1/9 Relapse; 6/9 Refractory) were classified as stable disease (SD). In-vitro functional profiling of 14 patients provided a correlation with the clinical outcome (p=0.01) irrespective of the stage of the disease. 100% of the patients identified as responders by functional profiling (n = 5), resulted in a CR outcome. 89% of the patients identified as non-responders (n = 9) resulted in an SD outcome. The same patient samples were also investigated for the molecular assessment of the most relevant genes commonly analyzed in AML patients. FLT3-ITD mutation was found in 2/14 patients, both in SD. Negative FLT3 was not correlated to clinical outcome. FLT3-TKD mutation was found in 3/14 patients, 2/3 resulted in CR, 1/3 in SD. TP53 mutation was found in 1/13 patients, classified as SD. Intronic variant rs1625895 was found in 6/13 patients equally distributed in CR and SD. NPM1 mutation was identified in 4/13 patients, 2/4 resulted in CR, 2/4 in SD indicating no direct correlation. IDH2 was found in 1/11 patients (with R172K mutation) with an SD. As a conclusion, functional profiling proved to be highly correlated with clinical outcome irrespective of patient stage and demonstrated a superior predictive power compared to molecular profiling. Citation Format: Laura Rocchi, Andrea Faenza, Viviana Guadagnuolo, Laura Rambelli, Giovanni Marconi, Maria Chiara Fontana, Martina Pazzaglia, Cristina Papayannidis, Giorgia Simonetti, Nicola Pecorari, Luca Giulianelli, Dario Biscarini, Marco Bettelli, Michele Federici, Rita Ruggiano, Giovanni Martinelli, Roberto Guerrieri, Massimo Bocchi. Lab-on-a-chip-based in-vitro functional profiling proves to be effective in predicting therapy outcome in AML patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3613.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2018
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...