Paradoxical antiproliferative effect by a murine mammary tumor-derived epithelial cell line

[Background] Despite significant advancement in breast cancer therapy, there is a great need for a better understanding of the mechanisms involved in breast carcinogenesis and progression, as well as of the role of epigenetic contributions from stromal cells in mammary tumorigenesis. In this study, we isolated and characterized murine mammary tumor-derived epithelial and myofibroblast cell lines, and investigated the in vitro and in vivo effect of cellular soluble factors produced by the epithelial cell line on tumor cells[Methods] Morphology, immunophenotype, cytogenetics, invasiveness, and tumorigenicity of epithelial (LM-234ep) and myofibroblast (LM-234mf) cell lines isolated from two murine mammary adenocarcinomas with common ancestor were studied. The in vitro effects of LM-234ep conditioned medium on proliferation, cell cycle distribution, and expression of cell cycle proteins, were investigated in LM-234mf cells, mouse melanoma cells (B16-F10), and human cervical adenocarcinoma cells (HeLa). The in vivo anti-tumor activity of LM-234ep conditioned media was evaluated in subcutaneous tumors formed in nude mice by B16-F10 and HeLa cells.[Results] LM-234ep cells were found to be cytokeratin positive and hipertriploid, whereas LM- 234mf cells were α-smooth muscle actin positive and hypohexaploid. Chromosome aberrations were found in both cases. Only LM-234mf revealed to be invasive in vitro and to secrete active MMP-2, though neither of the cell types were able to produce progressing tumors. LM-234epderived factors were able to inhibit the in vitro growth of LM-234mf, B16-F10, and HeLa cells, inducing cell cycle arrest in G0/G1 phase. The administration of LM-234ep conditioned medium inhibited the growth of B16-F10 and HeLa tumors in nude mice.[Conclusion] Our data suggest the existence of epithelial cell variants with tumor suppressive properties within mammary tumors. To our knowledge, this is the first report showing antiproliferative and antineoplastic activities induced by tumor-derived epithelial cells.This work was supported by Cancer Research Foundation (Fundación de Investigación del Cáncer, FUNDIC), Buenos Aires, Argentina.Peer reviewe

Immunotherapy for liver tumors: present status and future prospects

Increasing evidence suggests that immune responses are involved in the control of cancer and that the immune system can be manipulated in different ways to recognize and attack tumors. Progress in immune-based strategies has opened new therapeutic avenues using a number of techniques destined to eliminate malignant cells. In the present review, we overview current knowledge on the importance, successes and difficulties of immunotherapy in liver tumors, including preclinical data available in animal models and information from clinical trials carried out during the lasts years. This review shows that new options for the treatment of advanced liver tumors are urgently needed and that there is a ground for future advances in the field

Metastatic breast cancer patients treated with low-dose metronomic chemotherapy with cyclophosphamide and celecoxib: clinical outcomes and biomarkers of response

Background Preclinical results showing therapeutic effect and low toxicity of metronomic chemotherapy with cyclophosphamide (Cy) + celecoxib (Cel) for mammary tumors encouraged its translation to the clinic for treating advanced breast cancer patients (ABCP). Patients and methods A single-arm, mono-institutional, non-randomized, phase II, two-step clinical trial (approved by Bioethics Committee and Argentine Regulatory Authority) was designed. Patients received Cy (50 mg po.d) + Cel (200 mg p.o.bid). Patient eligibility criteria included: ABCP who progressed to anthracyclines, taxanes and capecitabine, ≤4 chemotherapy schemes, with good performance status. Several pro- and anti-angiogenic molecules and cells were determined as biomarkers. Informed consent was signed by all patients. Primary endpoint was clinical benefit (CB). Results Twenty patients were enrolled. Main clinical outcomes were prolonged disease stabilization and partial remission in 10/20 and 1/20 patients, respectively. CB was 55 %, and time to progression (TTP) was 21.1 weeks. Median TTP in patients who achieved CB was 35.6 weeks, and mean overall survival was 44.20 weeks. There were no grade 3/4 toxicities associated with treatment. Circulating endothelial cells (CECs) increased at the time of progression in patients who showed CB (P = 0.014). Baseline CECs and circulating endothelial progenitor cells showed marginal associations with TTP. Serum VEGF decreased (P = 0.050), sVEGFR-2 increased (P = 0.005) and VEGF/sVEGFR-2 ratio decreased during treatment (P = 0.041); baseline VEGF and VEGF/sVEGFR-2 were associated with TTP (P = 0.035 and P = 0.030, respectively), while sVEGFR-2 did not. Conclusions Treatment was effective, showing low toxicity profile and excellent tolerability. The combination had anti-angiogenic effect. Increased levels of CEC could be useful for detecting progression. Baseline VEGF and VEGF/sVEGFR-2 values could be useful as early predictors of response. Trial registration ANMAT#4596/09.Fil: Perroud, Herman A. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; ArgentinaFil: Alasino, Carlos María. Institute of Oncology of Rosario; ArgentinaFil: Rico, María José. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; ArgentinaFil: Mainetti, Leandro Ernesto. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; ArgentinaFil: Queralt, Francisco. Institute of Oncology of Rosario; ArgentinaFil: Pezzotto, Stella Maris. Research Council of the National University of Rosario (CIUNR); ArgentinaFil: Rozados, Viviana R. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; ArgentinaFil: Scharovsky, O. Graciela. Universidad Nacional de Rosario. Consejo de Investigaciones UNR, Facultad de Ciencias Médicas; Argentin

Reversal of gastrointestinal carcinoma-induced immunosuppression and induction of antitumoural immunity by a combination of cyclophosphamide and gene transfer of IL-12

Immunotherapy-based strategies for gastrointestinal carcinomas (GIC) have been exploited so far, but these approaches have to face strong mechanisms of immune escape induced by tumours. We previously demonstrated that sub-therapeutic doses of an adenovirus expressing IL-12 genes (AdIL-12) mediated a potent antitumour effect against subcutaneous (s.c.) colorectal carcinomas (CRC) in mice pre-treated with low doses of cyclophosphamide (Cy). In our study we used this combination to assess its impact on the immunosuppressive microenvironment. In s.c. CRC model we demonstrated that non-responder mice failed to decrease Tregs in tumour, spleen and peripheral blood. Reconstitution of Tregs into tumour-bearing mice treated with combined therapy abolished the antitumoural effect. In addition, Cy + AdIL-12 modified Tregs functionality by inhibiting the in vitro secretion of IL-10 and TGF-β and their ability to inhibit dendritic cells activation. Combined treatment decreased the number of myeloid-derived suppressor cells (MDSCs) in comparison to non-treated mice and, interestingly, administration of Tregs restored splenic MDSCs population. Furthermore, combined therapy potently generated specific cytotoxic IFN-γ-secreting CD4+ T cells able to eradicate established CRC tumours after adoptive transfer. Finally, we evaluated the combination on disseminated CRC and pancreatic carcinoma (PC). Cy + AdIL-12 were able to eradicate liver metastatic CRC (47%) and PC tumour nodules (40%) and to prolong animal survival. The results of this study support the hypothesis that Cy + AdIL-12 might be a valid immunotherapeutic strategy for advanced GIC.Fil: Malvicini, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Ingolotti, Mariana. Universidad Austral; ArgentinaFil: Piccioni, Flavia Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: García, Mariana Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Bayo Fina, Juan Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Atorrasagasti, María Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Alaniz, Laura Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Aquino, Jorge Benjamin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; ArgentinaFil: Espinoza, Jaime A.. Universidad Adolfo Ibañez; Chile. Universidad de La Frontera; ChileFil: Gidekel, Manuel. Universidad Adolfo Ibañez; ChileFil: Scharovsky, Olga Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Medicas. Instituto de Genetica Experimental; ArgentinaFil: Matar, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Medicas. Instituto de Genetica Experimental; ArgentinaFil: Mazzolini Rizzo, Guillermo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral; Argentin

Paradoxical antiproliferative effect by a murine mammary tumor-derived epithelial cell line

<p>Abstract</p> <p>Background</p> <p>Despite significant advancement in breast cancer therapy, there is a great need for a better understanding of the mechanisms involved in breast carcinogenesis and progression, as well as of the role of epigenetic contributions from stromal cells in mammary tumorigenesis. In this study, we isolated and characterized murine mammary tumor-derived epithelial and myofibroblast cell lines, and investigated the <it>in vitro </it>and <it>in vivo </it>effect of cellular soluble factors produced by the epithelial cell line on tumor cells.</p> <p>Methods</p> <p>Morphology, immunophenotype, cytogenetics, invasiveness, and tumorigenicity of epithelial (LM-234ep) and myofibroblast (LM-234mf) cell lines isolated from two murine mammary adenocarcinomas with common ancestor were studied. The <it>in vitro </it>effects of LM-234ep conditioned medium on proliferation, cell cycle distribution, and expression of cell cycle proteins, were investigated in LM-234mf cells, mouse melanoma cells (B16-F10), and human cervical adenocarcinoma cells (HeLa). The <it>in vivo </it>anti-tumor activity of LM-234ep conditioned media was evaluated in subcutaneous tumors formed in <it>nude </it>mice by B16-F10 and HeLa cells.</p> <p>Results</p> <p>LM-234ep cells were found to be cytokeratin positive and hipertriploid, whereas LM-234mf cells were α-smooth muscle actin positive and hypohexaploid. Chromosome aberrations were found in both cases. Only LM-234mf revealed to be invasive <it>in vitro </it>and to secrete active MMP-2, though neither of the cell types were able to produce progressing tumors. LM-234ep-derived factors were able to inhibit the <it>in vitro </it>growth of LM-234mf, B16-F10, and HeLa cells, inducing cell cycle arrest in G₀/G₁phase. The administration of LM-234ep conditioned medium inhibited the growth of B16-F10 and HeLa tumors in <it>nude </it>mice.</p> <p>Conclusion</p> <p>Our data suggest the existence of epithelial cell variants with tumor suppressive properties within mammary tumors. To our knowledge, this is the first report showing antiproliferative and antineoplastic activities induced by tumor-derived epithelial cells.</p

Terapia génica: el desafío terapéutico del siglo XXI

La terapia génica es una forma de medicina molecular que probablemente tendrá un gran impacto en la salud humana a lo largo del siglo XXI. Tiene como objetivo modificar o reparar una alteración genética adquirida, corregir un error génico de nacimiento o dotar a una célula con una nueva función. Los avances recientes de la Biología Molecular y de la tecnología del ADN recombinante han hecho posible el desarrollo de este tipo de enfoque terapéutico. Esta novedosa metodología puede llegar a tener profundas implicancias en la forma en que se traten las enfermedades en el futuro. Se describen los distintos tipos de terapia génica que se están desarrollando en la actualidad, los requisitos que se deben cumplir para poder aplicarlos eficientemente, las desventajas de cada método, los genes más comúnmente transducidos y sus vías de administración. También se analizan las patologías hereditarias o adquiridas que son susceptibles de ser tratadas con terapia génica, tales como enfermedades neoplásicas, infecciosas, del sistema inmune o que afectan a diferentes órganos, así como las distintas estrategias implementadas para llevarla a cabo

Clinical response in patients with ovarian cancer treated with metronomic chemotherapy

Ovarian cancer (OC) is the leading cause of death from gynaecological cancer. It is extremely hard to diagnose in the early stages and around 70% of patients present with advanced disease. Metronomic chemotherapy (MCT) is described as the chronic administration of, generally low, equally spaced, doses of chemotherapeutic drugs with therapeutic efficacy and low toxicity. This is an effective and low-cost way to treat several types of tumours, including ovarian cancer. Here, we present six cases of advanced ovarian cancer treated with MCT with low doses of cyclophosphamide, which showed clinical response and stable disease.Fil: Perroud, Herman A. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; ArgentinaFil: Scharovsky, Graciela Olga. Universidad Nacional de Rosario. Consejo de Investigaciones UNR, Facultad de Ciencias Médicas; ArgentinaFil: Rozados, Viviana R. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; ArgentinaFil: Alasino, Carlos María. Institute of Oncology of Rosario; Argentin

Modulation of IL-10/IL-10R expression by mafosfamide, a derivative of 4-hydroxycyclophosphamide, in a rat B-cell lymphoma

We have already shown that IL-10 plays an important role in immunosuppression and metastatic dissemination in the rat B-cell lymphoma L-TACB model. It was suggested that the up-regulation of IL-10 production and IL-10 receptor (IL-10R) expression would be part of the transition from primary tumor to metastatic phenotype and that IL-10, besides its immunosuppressive activity, may act as a growth factor for metastatic L-TACB cells. The treatment of L-TACB-bearing rats with a single low-dose cyclophosphamide decreased IL-10 production, reverted immunosuppression and induced the immunologic rejection of tumor metastasis without any effect on primary tumor growth. Our current aim was to investigate the effects of cyclophosphamide on the expression of IL-10 and IL-10R on primary and metastatic L-TACB cells. Considering that cyclophosphamide is a prodrug, we used mafosfamide, a compound that yields in vitro the same active metabolites as cyclophosphamide does in vivo. Mafosfamide induced down-regulation of IL-10 production and IL-10R expression on metastatic cells and, concomitantly, inhibited metastatic cell proliferation. We suggest that mafosfamide would inhibit the regulatory loop mediated by the IL-10/IL-10R system and, as a consequence, metastatic cell proliferation. These results may have a considerable impact on the design of new therapies for metastatic lymphomas.Fil: Rico, María José. Universidad Nacional de Rosario. Instituto de Genética Experimental; Facultad de Ciencias Médicas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET);Argentina.Fil: Matar, Pablo. Universidad Nacional de Rosario. Instituto de Genética Experimental; Facultad de Ciencias Médicas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET);Argentina.Fil: Scharovsky, O. Graciela. Universidad Nacional de Rosario. Instituto de Genética Experimental; Facultad de Ciencias Médicas. Consejo Nacional de Investigaciones UNR; Argentina

From immune surveillance to tumor-immune escape: the story of an enemy with multiple strategies of resistance and counterattack

Tumors must circumvent the immune response of the host to become clinically detectable. For this purpose, malignant cells have devised multiple strategies to thwart immune attack. These mechanisms are suggested to conspire in advanced stages of cancer to limit the ability of the immune system to restrain the tumor and the effectiveness of immunotherapy strategies to successfully eradicate malignant cells. From tumor biology to cancer immunotherapy and back again, we will summarize here some of the most important mechanisms used by tumors to evade the immune response and their potential impact in the design of cancer immunotherapy strategies.Los tumores deben evadir la respuesta inmunológica para ser clínicamente detectables en el paciente. A estos fines, las células cancerosas han desarrollado múltiples estrategias para eludir el ataque inmunológico. Estos mecanismos conspiran en estadíos avanzados de un tumor limitando la habilidad del sistema inmune para inhibir el crecimiento tumoral y la efectividad de estrategias de inmunoterapia en cáncer. Desde la biología tumoral a la clínica, en el presente artículo expondremos los más importantes mecanismos utilizados por tumores para evadir la respuesta inmunológica y su potencial impacto en el diseño de estrategias de inmunoterapia