RESUMO
Mollusk hemocyanins have been used for decades in immunological and clinical applications as natural, nontoxic, nonpathogenic, and nonspecific immunostimulants for the treatment of superficial bladder cancer, as carriers/adjuvants of tumor-associated antigens in cancer vaccine development and as adjuvants to dendritic cell-based immunotherapy, because these glycoproteins induce a bias towards Th1 immunity. Here, we analyzed the preclinical therapeutic potential of the traditional keyhole limpet hemocyanin (KLH) and two new hemocyanins from Concholepas concholepas (CCH) and Fissurella latimarginata (FLH) in mouse models of oral squamous cell carcinoma. Due to the aggressiveness and deadly malignant potential of this cancer, the hemocyanins were applied in combination with adjuvants, such as alum, AddaVax, and QS-21, which have been shown to be safe and effective in human vaccines, to potentiate their antitumor activity. The immunogenic performance of the hemocyanins in combination with the adjuvants was compared, and the best formulation was evaluated for its antitumor effects in two murine models of oral cancer: MOC7 cells implanted in the flank (heterotopic) and bioluminescent AT-84 E7 Luc cells implanted in the floor of the mouth (orthotopic). The results demonstrated that the hemocyanins in combination with QS-21 showed the greatest immunogenicity, as reflected by a robust, specific humoral response predominantly characterized by IgG2a antibodies and a sustained cellular response manifesting as a delayed hypersensitivity reaction. The KLH- and FLH-QS-21 formulations showed reduced tumor development and greater overall survival. Hemocyanins, as opposed to QS-21, had no cytotoxic effect on either oral cancer cell line cultured in vitro, supporting the idea that the antitumor effects of hemocyanins are associated with their modulation of the immune response. Therefore, hemocyanin utilization would allow a lower QS-21 dosage to achieve therapeutic results. Overall, our study opens a new door to further investigation of the use of hemocyanins plus adjuvants for the development of immunotherapies against oral carcinoma.
Assuntos
Adjuvantes Imunológicos/uso terapêutico , Hemocianinas/uso terapêutico , Imunoterapia , Neoplasias Bucais/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Hemocianinas/química , Imunidade Celular , Imunidade Humoral , Camundongos , Camundongos Endogâmicos C57BL , Moluscos/química , Polissorbatos/administração & dosagem , Saponinas/administração & dosagem , Esqualeno/administração & dosagemRESUMO
The immune system is composed of immune as well as non-immune cells. As this system is a well-established component of human papillomavirus- (HPV)-related carcinogenesis, high risk human papillomavirus (hrHPV) prevents its routes and mechanisms in order to cause the persistence of infection. Among these mechanisms are those originated from stromal cells, which include the cancer-associated fibroblasts (CAFs), the myeloid-derived suppressor cells (MDSCs) and the host infected cells themselves, i.e. the keratinocytes. These types of cells play central role since they modulate immune cells activities to create a prosperous milieu for cancer development, and the knowledge how such interactions occur are essential for prognostic assessment and development of preventive and therapeutic approaches. Nevertheless, the precise mechanisms are not completely understood, and this lack of knowledge precluded the development of entirely efficient immunotherapeutic strategies for HPV-associated tumors. As a result, an intense work for attaining how host immune response works, and developing of effective therapies has been applied in the last decade. Based on this, this review aims to discuss the major mechanisms of immune and non-immune cells modulated by hrHPV and the potential and existing immunotherapies involving such mechanisms in HPV-related cancers. It is noticed that the combination of immunotherapies has been demonstrated to be essential for obtaining better results, especially because the possibility of increasing the modulating capacity of the HPV-tumor microenvironment has been shown to be central in strengthening the host immune system.
Assuntos
Neoplasias/etiologia , Neoplasias/patologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Células Estromais/metabolismo , Animais , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Evasão da Resposta Imune , Imunoterapia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Mastócitos/imunologia , Mastócitos/metabolismo , Mastócitos/patologia , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Neoplasias/metabolismo , Neoplasias/terapia , Células Estromais/patologia , Microambiente Tumoral/imunologiaRESUMO
The modulation of the host innate immune system is a well-established carcinogenesis feature of several tumors, including human papillomavirus- (HPV-) related cancers. This virus is able to interrupt the initial events of the immune response, including the expression of Toll-like receptors (TLRs), cytokines, and inflammation. Both TLRs and cytokines play a central role in HPV recognition, cell maturation and differentiation as well as immune signalling. Therefore, the imbalance of this sensitive control of the immune response is a key factor for developing immunotherapies, which strengthen the host immune system to accomplish an efficient defence against HPV and HPV-infected cells. Based on this, the review is aimed at exposing the HPV immune evasion mechanisms involving TLRs and cytokines and at discussing existing and potential immunotherapeutic TLR- and cytokine-related tools.
Assuntos
Citocinas/metabolismo , Imunoterapia/métodos , Neoplasias/imunologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/imunologia , Receptores Toll-Like/metabolismo , Animais , Transformação Celular Neoplásica , Humanos , Evasão da Resposta Imune , Neoplasias/virologia , Infecções por Papillomavirus/virologiaRESUMO
INTRODUCTION: Cervical cancer and cervical intraepithelial neoplasia (CIN) are well-known outcomes of a human papillomavirus (HPV) infection. Viral oncogenes expressions like E6, E7, and, recently recognized E5, lead to HPV-related malignant progression. Although HPV prevention by powerful vaccines against most frequent and oncogenic genotypes is feasible, current treatment against cervical neoplasia is distant from an ideal one. In addition, late diagnosis is commonly associated with a poor prognosis. On top of that, radiotherapy, chemotherapy, or surgery are less effective in high-grade lesions. Areas covered: Due to their peculiarities, HPV oncogenes represent an excellent target for cancer immunotherapy. Safety, efficacy, and potential immunogenicity are features achieved by DNA vaccines targeting HPV. The literature search has indicated that genetic immunotherapy is becoming a pharmacological tool and therapeutic option against cervical disease, as more and more DNA vaccines are reaching clinical trial phases. Expert commentary: Among some of the promising results, a phase II randomized trial showed a clinical activity of a nucleic acid-based vaccine in HPV16 or HPV18 positive CIN patients. The concept of a synergic combination of anti-HPV DNA vaccines with radiotherapy, chemotherapy, sophisticated delivery methods, immunomodulators or immune adjuvants opens a new and interesting perspective in cervical malignancy treatment.
Assuntos
Vacinas Anticâncer/administração & dosagem , Displasia do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Animais , Vacinas Anticâncer/imunologia , Feminino , Humanos , Imunoterapia/métodos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/imunologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/virologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Displasia do Colo do Útero/imunologia , Displasia do Colo do Útero/virologiaRESUMO
The immune response is a key factor in the fight against HPV infection and related cancers, and thus, HPV is able to promote immune evasion through the expression of oncogenes. In particular, the E5 oncogene is responsible for modulation of several immune mechanisms, including antigen presentation and inflammatory pathways. Moreover, E5 was suggested as a promising therapeutic target, since there is still no effective medical therapy for the treatment of HPV-related pre-neoplasia and cancer. Indeed, several studies have shown good prospective for E5 immunotherapy, suggesting that it could be applied for the treatment of pre-cancerous lesions. Thus, insofar as the majority of cervical, oropharyngeal and anal cancers are caused by high-risk HPV (hrHPV), mainly by HPV16, the aim of this review is to discuss the immune pathways interfered by E5 oncoprotein of hrHPV highlighting the various aspects of the potential immunotherapeutic approaches.
Assuntos
Evasão da Resposta Imune , Imunomodulação , Proteínas Oncogênicas Virais/imunologia , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/fisiologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Animais , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Imunoterapia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/terapia , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Replicação ViralRESUMO
Expression of HPV E5, E6 and E7 oncogenes are likely to overcome the regulation of cell proliferation and to escape immunological control, allowing uncontrolled growth and providing the potential for malignant transformation. Thus, their three oncogenic products may represent ideal target antigens for immunotherapeutic strategies. In previous attempts, we demonstrated that genetic vaccines against recombinant HPV16 E7 antigen were able to affect the tumor growth in a pre-clinical mouse model. To improve this anti-HPV strategy we developed a novel approach in which we explored the effects of E5-based genetic immunization. We designed novel HPV16 E5 genetic vaccines based on two different gene versions: whole E5 gene and E5Multi. The last one is a long multi epitope gene designed as a harmless E5 version. Both E5 genes were codon optimized for mammalian expression. In addition, we demonstrated that HPV 16 E5 oncogene is expressed in C3 mouse cell line making it an elective model for the study of E5 based vaccine. In this mouse model the immunological and biological activity of the E5 vaccines were assessed in parallel with the activity of anti-E7 and anti-E6 vaccines already reported to be effective in an immunotherapeutic setting. These E7 and E6 vaccines were made with mutated oncogenes, the E7GGG mutant that does not bind pRb and the E6F47R mutant that is less effective in inhibiting p53, respectively. Results confirmed the immunological activity of genetic formulations based on attenuated HPV16 oncogenes and showed that E5-based genetic immunization provided notable anti-tumor effects.