RESUMO
Anti-CD20 monoclonal antibodies (MAbs) have revolutionized the treatment of B-cell leukemia and lymphoma. However, many patients do not respond to such treatment due to either deficiency of the complementary immune response or resistance to apoptosis. Other currently available treatments are often inadequate or induce major side effects. Therefore, there is a constant need for improved therapies. The prostaglandin E2 receptor 4 (EP4) receptor has been identified as a promising therapeutic target for hematologic B-cell malignancies. Herein, we report that EP4 receptor agonists PgE1-OH and L-902688 have exhibited enhanced cytotoxicity when applied together with anti-CD20 MAbs rituximab, ofatumumab and obinutuzumab in vitro in Burkitt lymphoma cells Ramos, as well as in p53-deficient chronic lymphocytic leukemia (CLL) cells MEC-1. Moreover, the enhanced cytotoxic effects of EP4 receptor agonists and MAbs targeting CD20 have been identified ex vivo on primary lymphocytes B obtained from patients diagnosed with CLL. Incubation of cells with PgE1-OH and L-902688 preserved the expression of CD20 molecules, further confirming the anti-leukemic potential of EP4 receptor agonists in combination with anti-CD20 MAbs. Additionally, we demonstrated that the EP4 receptor agonist PgE-1-OH induced apoptosis and inhibited proliferation via the EP4 receptor triggering in CLL. This work has revealed very important findings leading towards the elucidation of the anticancer potential of PgE1-OH and L-902688, either alone or in combination with MAbs. This may contribute to the development of potential therapeutic alternatives for patients with B-cell malignancies.
Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD20/imunologia , Leucemia de Células B/metabolismo , Linfoma de Células B/metabolismo , Receptores de Prostaglandina E Subtipo EP4/agonistas , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Humanos , Leucemia de Células B/tratamento farmacológico , Linfoma de Células B/tratamento farmacológico , Pirrolidinonas/farmacologia , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Rituximab/farmacologia , Rituximab/uso terapêutico , Tetrazóis/farmacologiaRESUMO
We report on the design, synthesis, and biological evaluation of a series of nucleotide-binding oligomerization-domain-containing protein 2 (NOD2) desmuramylpeptide agonists with improved in vitro and in vivo adjuvant properties. We identified two promising compounds: 68, a potent nanomolar in vitro NOD2 agonist, and the more lipophilic 75, which shows superior adjuvant activity in vivo. Both compounds had immunostimulatory effects on peripheral blood mononuclear cells at the protein and transcriptional levels, and augmented dendritic-cell-mediated activation of T cells, while 75 additionally enhanced the cytotoxic activity of peripheral blood mononuclear cells against malignant cells. The C18 lipophilic tail of 75 is identified as a pivotal structural element that confers in vivo adjuvant activity in conjunction with a liposomal delivery system. Accordingly, liposome-encapsulated 75 showed promising adjuvant activity in mice, surpassing that of muramyl dipeptide, while achieving a more balanced Th1/Th2 immune response, thus highlighting its potential as a vaccine adjuvant.
Assuntos
Acetilmuramil-Alanil-Isoglutamina/química , Adjuvantes Imunológicos/química , Proteína Adaptadora de Sinalização NOD2/agonistas , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacologia , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Formação de Anticorpos/efeitos dos fármacos , Linhagem Celular , Desenho de Fármacos , Humanos , Imunoglobulina G/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipossomos/química , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Adaptadora de Sinalização NOD2/metabolismo , Ovalbumina/imunologia , Relação Estrutura-Atividade , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/citologia , Células Th2/imunologia , Células Th2/metabolismoRESUMO
Treatment of patients with relapsed or refractory chronic lymphocytic leukemia (CLL) has significantly improved more recently with the approval of several new agents, including ibrutinib, idelalisib, and venetoclax. Despite the outstanding efficacies observed with these agents, these treatments are sometimes discontinued due to toxicity, unresponsiveness, transformation of the disease and/or resistance. Constitutive NF-κB activation that protects CLL cells from apoptotic stimuli represents one of molecular mechanisms that underlie the emergence of drug resistance. As prostaglandin E (EP)4 receptor agonists have been shown to successfully inhibit the NF-κB pathway in B-cell lymphoma cells, we investigated the potential of the highly specific EP4 receptor agonist L-902688 for the potential treatment of patients with CLL. We show here that low micromolar concentrations of L-902688 can indeed induce selective cytotoxicity towards several B-cell malignancies, including CLL. Moreover, L-902688-mediated activation of the EP4 receptor in patient derived CLL cells resulted in inhibition of the NF-κB pathway, cell proliferation, and induction of apoptosis. Most importantly, we show for the first time that in combination with ibrutinib, idelalisib, or venetoclax, L-902688 induces synergistic cytotoxic activity against patient derived CLL cells. To conclude, the modulation of NF-κB activity by EP4 receptor agonists represents an innovative approach to improve the treatment of patients with CLL. In particular, EP4 receptor agonists appear to represent promising adjuncts to the already existing therapies for patients with CLL due to these promising synergistic activities.
Assuntos
Adenina/análogos & derivados , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Leucemia Linfocítica Crônica de Células B , Piperidinas/administração & dosagem , Purinas/administração & dosagem , Pirrolidinonas/administração & dosagem , Quinazolinonas/administração & dosagem , Receptores de Prostaglandina E Subtipo EP4/agonistas , Sulfonamidas/administração & dosagem , Tetrazóis/administração & dosagem , Adenina/administração & dosagem , Adulto , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Células Jurkat , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Células U937RESUMO
In the last decade, cancer immunotherapy has emerged as an effective alternative to traditional therapies such as chemotherapy and radiation. In contrast to the latter, cancer immunotherapy has the potential to distinguish between cancer and healthy cells, and thus to avoid severe and intolerable side-effects, since the cancer cells are effectively eliminated by stimulated immune cells. The cytosolic nucleotide-binding oligomerization domains 1 and 2 receptors (NOD1 and NOD2) are important components of the innate immune system and constitute interesting targets in terms of strengthening the immune response against cancer cells. Many NOD ligands have been synthesized, in particular NOD2 agonists that exhibit favorable immunostimulatory and anticancer activity. Among them, mifamurtide has already been approved in Europe by the European Medicine Agency for treating patients with osteosarcoma in combination with chemotherapy after complete surgical removal of the primary tumor. This review is focused on NOD receptors as promising targets in cancer immunotherapy as well as summarizing current knowledge of the various NOD ligands exhibiting antitumor and even antimetastatic activity in vitro and in vivo.