The E6/E7 oncogenes of human papilloma virus and estradiol regulate hedgehog signaling activity in a murine model of cervical cancer.

Human papilloma virus oncogenes and estradiol are major etiologic factors associated with cervical cancer. In order to understand the mechanism by which these two factors promote carcinogenesis, the role of the Hedgehog (Hh) signaling pathway was evaluated during the normal growth of cervical epithelium and in the presence of E6/E7 oncogenes and exogenous estradiol. Hh signaling activity was determined in live animals (i.e., Gli-Luc reporter levels) during the estrous cycle and was found to be higher in the cervical area during the major growth phases, proestrus-estrus, in comparison to the diestrus phase. The same pattern was observed in transgenic mice expressing the E6/E7 oncogenes, though with notably higher levels than in control mice. Adding estradiol also markedly increased Gli activity in the cervix and the skin. In agreement with the correlation between high bioluminescence and tissue growth in different context, cervical cell proliferation was reduced upon Hh signaling inhibition in mice. Treatment with itraconazole, a putative novel Hh inhibitor, at an early stage of cervical carcinogenesis, did not decrease Hh signaling but it did reduce growth. Therefore, Hh signaling likely contributes to cervical carcinogenesis and itraconazole is effective to reduce growth but by a mechanism involving additional signaling pathways.

Hedgehog signaling dynamics in mouse embryos determined by a bioluminiscent reporter.

Determination of cellular signaling in live embryos is key to understand the molecular processes that drive development. Here, we show that a transgenic mouse line carrying a luciferase-based gene reporter of Gli-mediated transcriptional activation (Gli-Luc) displays sonic hedgehog (Shh) signaling in discrete developmental processes during short-term cultures of whole embryos or embryo explants. The bioluminescence in E9.5 embryos was detected in regions in which Shh activity has been demonstrated. Later, in E10.5 embryos, bioluminescence intensity markedly increased, mostly corresponding to the high Shh activity of the developing midbrain and limb. Notably, the dynamic range of the Gli-Luc reporter in the developing limb revealed the progressive emergence of bioluminescence in the zone of polarizing activity, where reporter activity locally increased and spatially spread in agreement with the signaling gradient expected for Shh. In the midbrain of E9.5 mouse embryos, bioluminescence was not detected along the ventral region as expected but, instead, Shh-dependent anterior and posterior bioluminescence foci emerged by E10.5 indicating that the Gli-Luc reporter can only respond transcriptionally to relatively high levels of GliA and/or without the interaction with other transcription factors. The present work supports the use of bioluminescence to identify and study the dynamics of centers of morphogen signaling during mouse embryogenesis.

Relationship of dendritic cell density, HMGB1 expression, and tumor-infiltrating lymphocytes in non-small cell lung carcinomas.

Lung cancer is the leading cause of cancer death worldwide and non-small cell lung carcinoma (NSCLC) is the most common type of lung carcinomas. In adenocarcinomas, the most frequent histologic type of NSCLC, dendritic cells (DCs) are localized in close contact with tumor cells, and tumor-infiltrating lymphocytes (TILs) are observed in the peritumoral zones. In NSCLC, no studies investigating the density of intratumoral DCs and their impact on the density of TILs have been performed. In addition, the role of the alarmin high-mobility group box1 (HMGB1) in intratumoral DCs recruitment has not been analyzed. In the present study, a total of 82 cases of advanced stages of NSCLC were included. Tissue samples were obtained from biopsies and autopsies. DCs in biopsies or combinations of DCs and NK cells, CD3 T lymphocytes, or CD8 T lymphocytes from autopsy specimens were quantified in high power fields. Also, distribution of HMGB1 in tumor cells was detected. In lung adenocarcinomas, irrespective of subclassification, high densities of infiltrating DCs directly associated to high densities of peritumoral TILs. A 2.5-fold increase in TILs was found in specimens with high densities of infiltrating DCs compared with TILs from adenocarcinomas with low densities of infiltrating DCs. High densities of infiltrating DCs were associated with lung adenocarcinomas expressing cytoplasmic or nuclear-cytoplasmic HMGB1. Our results suggest that in adenocarcinoma patients, HMGB1 produced by tumor cells recruits DCs, which associate to an increase of TILs. Encouraging tumor-DCs-T lymphocytes interactions should improve the quality of life and survival of NSCLC patients.

[Participation of damage-associated molecular patterns in conventional treatment of cancer]. / Participación de los patrones moleculares asociados al daño en el tratamiento convencional del cáncer.

Cells of the innate immune system are involved in discriminating between the innocuous cell death (apoptosis) which occurs in tissues during homeostasis, and the cell death associated to tissue damage (necrosis). Recently, a new variant of apoptosis termed immunogenic apoptosis has been described. In cancer, this type of cell death has acquired great relevance. In vitro and in vivo experimental models support that radiotherapy and some chemotherapeutic drugs induce the immunogenic apoptosis of malignant cells. Dying cells express at cytoplasmic membrane or release several nuclear or intracytoplasmic molecules termed "danger signals" or damage associated molecular patterns (DAMPs). DAMPs alert the organism and play a role inducing an efficient anti-tumor immune response. In this review, the importance of cell death by immunogenic apoptosis, the cytotoxic drugs that induce this type of cell death, the biologic role of some DAMPs and their participation in the activation of the antitumor immune response, in particular in the phagocytic cell, are indicated. The goal of this information should impact in improving the participation of the immune system in the recognition and efficient elimination of the residual tumor cells and to overcome the evasion mechanisms of tumor cells. This knowledge should lead to a better control of the growth of tumors with a concomitant reduction in the tumor recurrence. Also, an increase in the survival of the cancer patients or probably their definitive cure could be reached in the future.