RESUMO
Tumor-draining lymph nodes (tumor-DLNs) provide a rich source of tumor-reactive lymphocytes which can be used in adoptive immunotherapy (AIT) and that circumvent the need to resect autologous tumor, without the challenges and shortcomings associated with using autologous tumor or anti-CD3 monoclonal antibody. Bryostatin/Ionomycin (Bryo/Io) provide a useful method of activating tumor-DLNs such that they can readily be expanded to sufficient numbers to be used in AIT, and growing the tumor-DLN lymphocytes in the gamma chain cytokines IL-7 plus IL-15 is superior to IL-2 in terms of T cell numbers and phenotype. AIT with these cells induces tumor regression and provides protection against metastases and future tumor challenge. Here, we provide a stepwise protocol to sensitize tumor-DLN cells in donor mice, activate tumor-DLN T cells ex vivo using Bryo/Io, expansion of these cells in gamma chain cytokines and adoptive transfer of the expanded cells back into tumor-bearing hosts. Methods relevant to these experiments, such as injecting tumor cells intravenously and monitoring for pulmonary metastases, tumor volume measurement and resection, and use of luciferase-expressing tumor cells to monitor for metastases following resection, are described in detail. The methods outlined herein can be easily adapted to suit similar experiments across multiple tumor cell lines and syngeneic mouse models.
Assuntos
Citocinas , Imunoterapia Adotiva , Camundongos , Animais , Imunoterapia Adotiva/métodos , Briostatinas , Ionomicina/farmacologia , Linfonodos , Ativação Linfocitária , Camundongos Endogâmicos C57BLRESUMO
Small molecule activators of protein kinase C (PKC) have traditionally been classified as either tumor promoters or suppressors. Although bryostatin 1 has well established anti-cancer activity, most natural products that target the PKC regulator domain exhibit tumor promotion properties. In this study, we examine a focused library of indolactam analogues in cell-based assays to establish the structural features of the scaffold that enhance bryostatin 1-like activity. These systematic biological assessments identified specific indole substitution patterns that impart diminished tumor promotion behavior in vitro for indolactam analogues, while still maintaining nanomolar potency for PKC.
Assuntos
Lactamas , Neoplasias , Proteína Quinase C , Humanos , Briostatinas/farmacologia , Briostatinas/química , Briostatinas/metabolismo , Lactonas , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol , Lactamas/química , Lactamas/farmacologiaRESUMO
Protein kinase C delta (PKC-δ) is an important signaling molecule in human cells that has both proapoptotic as well as antiapoptotic functions. These conflicting activities can be modulated by two classes of ligands, phorbol esters and bryostatins. Phorbol esters are known tumor promoters, while bryostatins have anti-cancer properties. This is despite both ligands binding to the C1b domain of PKC-δ (δC1b) with a similar affinity. The molecular mechanism behind this discrepancy in cellular effects remains unknown. Here, we have used molecular dynamics simulations to investigate the structure and intermolecular interactions of these ligands bound to δC1b with heterogeneous membranes. We observed clear interactions between the δC1b-phorbol complex and membrane cholesterol, primarily through the backbone amide of L250 and through the K256 side-chain amine. In contrast, the δC1b-bryostatin complex did not exhibit interactions with cholesterol. Topological maps of the membrane insertion depth of the δC1b-ligand complexes suggest that insertion depth can modulate δC1b interactions with cholesterol. The lack of cholesterol interactions suggests that bryostatin-bound δC1b may not readily translocate to cholesterol-rich domains within the plasma membrane, which could significantly alter the substrate specificity of PKC-δ compared to δC1b-phorbol complexes.
Assuntos
Forbóis , Proteína Quinase C-delta , Humanos , Briostatinas , Isoenzimas/metabolismo , Ésteres de Forbol/química , Lactonas/químicaRESUMO
INTRODUCTION: HIV-1 eradication is hindered by the presence of inducible long-lived reservoirs of latently infected cells which rapidly disseminate viral particles upon treatment interruption. Eliminating these reservoirs by the so-called shock and kill strategy represents a crucial concept toward an HIV-1 cure. Several molecules called latency-reversing agents (LRAs) are under intensive investigations to reactivate virus gene expression. These studies are mainly conducted on CD4+ T cells where LRAs are well tolerated and did not induce global cellular activation. However, despite their broad spectrum, the putative impact of LRAs on other cellular reservoirs such as macrophages is still ill-defined. METHODS: We investigated the impact of the protein kinase C (PKC) activator bryostatin-1, bromodomain inhibitor JQ1 and histone deacetylase inhibitor romidepsin used either alone or in combination on human primary monocyte-derived macrophages (MDMs). RESULTS: We demonstrate that bryostatin-1, JQ1, and romidepsin or their combinations are not toxic at nanomolar concentrations but induce metabolic and morphologic alterations of MDMs. Bryostatin-1 triggered the secretion of pro-inflammatory cytokines, while JQ-1 decreased it. Phagocytosis and endocytosis were modestly impaired upon bryostatin-1 treatment whereas efferocytosis was markedly downregulated by romidepsin. Despite its pro-inflammatory profile, bryostatin-1 did not induce classically activated macrophage markers. Finally, we reveal that conditioned medium from bryostatin-1-treated macrophages did not potentiate its reactivation feature. CONCLUSIONS: Our study reveals that LRAs can diversely impact basic physiologic features of human primary macrophages and could potentially decrease reactivation of nearby CD4+ T cells latently infected with HIV-1. Our observations further stress the need to include different cell populations when assessing HIV-1 cure strategies.
Assuntos
Infecções por HIV , Soropositividade para HIV , Humanos , Ativação Viral , Latência Viral , Briostatinas/farmacologia , Briostatinas/uso terapêutico , Linfócitos T CD4-Positivos , Infecções por HIV/tratamento farmacológico , MacrófagosRESUMO
PURPOSE: DNMT3A mutations confer a poor prognosis in acute myeloid leukemia (AML), but the molecular mechanisms downstream of DNMT3A mutations in disease pathogenesis are not completely understood, limiting targeted therapeutic options. The role of miRNA in DNMT3A-mutant AML pathogenesis is understudied. EXPERIMENTAL DESIGN: DNA methylation and miRNA expression was evaluated in human AML patient samples and in Dnmt3a/Flt3-mutant AML mice. The treatment efficacy and molecular mechanisms of TLR7/8-directed therapies on DNMT3A-mutant AML were evaluated in vitro on human AML patient samples and in Dnmt3a/Flt3-mutant AML mice. RESULTS: miR-196b is hypomethylated and overexpressed in DNMT3A-mutant AML and is associated with poor patient outcome. miR-196b overexpression in DNMT3A-mutant AML is important to maintain an immature state and leukemic cell survival through repression of TLR signaling. The TLR7/8 agonist resiquimod induces dendritic cell-like differentiation with costimulatory molecule expression in DNMT3A-mutant AML cells and provides a survival benefit to Dnmt3a/Flt3-mutant AML mice. The small molecule bryostatin-1 augments resiquimod-mediated AML growth inhibition and differentiation. CONCLUSIONS: DNMT3A loss-of-function mutations cause miRNA locus-specific hypomethylation and overexpression important for mutant DNMT3A-mediated pathogenesis and clinical outcomes. Specifically, the overexpression of miR-196b in DNMT3A-mutant AML creates a novel therapeutic vulnerability by controlling sensitivity to TLR7/8-directed therapies.
Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Animais , Briostatinas/uso terapêutico , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Metilases de Modificação do DNA/genética , Humanos , Imunidade Inata , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos , MicroRNAs/genética , MicroRNAs/uso terapêutico , Mutação , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/uso terapêuticoRESUMO
The advent of CAR-T cell therapy has changed the face of clinical care for relapsed and refractory pre-B-acute lymphocytic leukemia (B-ALL) and lymphoma. Although curative responses are reported, long-term cures remain below 50%. Different CAR T-cell leukemia targets appear to have different mechanisms of CAR-T escape. For CD22, therapeutic evasion is linked to down-modulation of the number CD22 proteins expressed on the extracellular aspect of the leukemia cell plasma membrane. Recently, pharmacologic agents known to induce cellular differentiation or epigenetic modification of leukemia have been shown to impact CD22 and CD19 expression levels on B-ALL, and thereby increase sensitivity to CAR-T mediated cytolysis. We explored the impact of epigenetic modifiers and differentiation agents on leukemia cell lines of B cell origin, as well as normal B cells. We confirmed the activity of bryostatin to increase CD22 expression on model cell lines. However, bryostatin does not change CD22 levels on normal B cells. Furthermore, bryostatin inhibited CAR-T mediated cytolysis of the Raji Burkitt lymphoma cell line. Bryostatin increased the cytolysis by CD22 CAR-T for B-ALL cell lines by at least three mechanisms: 1) the previously reported increase in CD22 target cell numbers on the cell surface, 2) the induction of NK ligands, and 3) the induction of ligands that sensitize leukemia cells to activated T cell antigen-non-specific killing. The opposite effect was seen for Burkitt lymphoma, which arises from a more mature B cell lineage. These findings should caution investigators against a universal application of agents shown to increase killing of leukemia target cells by CAR-T in a specific disease class, and highlights that activation of non-CAR-mediated killing by activated T cells may play a significant role in the control of disease. We have termed the killing of leukemia targets, by a set of cell-surface receptors that does not overlap with NK-like killing "CTAK," CAR-T Cell antigen-non-specific killing.
Assuntos
Linfoma de Burkitt , Linfoma de Células B , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores de Antígenos Quiméricos , Briostatinas/farmacologia , Linfoma de Burkitt/terapia , Linhagem Celular , Humanos , Ligantes , Linfoma de Células B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Linfócitos TRESUMO
Yes-associated protein 1 (YAP1) interacts with TEAD transcription factor in the nucleus and upregulates TEAD-target genes. YAP1 is phosphorylated by large tumor suppressor (LATS) kinases, the core kinases of the Hippo pathway, at 5 serine residues and is sequestered and degraded in the cytoplasm. In human cancers with the dysfunction of the Hippo pathway, YAP1 becomes hyperactive and confers malignant properties to cancer cells. We have observed that cold shock induces protein kinase C (PKC)-mediated phosphorylation of YAP1. PKC phosphorylates YAP1 at 3 serine residues among LATS-mediate phosphorylation sites. Importantly, PKC activation recruits YAP1 to the cytoplasm even in LATS-depleted cancer cells and reduces the cooperation with TEAD. PKC activation induces promyelocytic leukemia protein-mediated SUMOylation of YAP1. SUMOylated YAP1 remains in the nucleus, binds to p73, and promotes p73-target gene transcription. Bryostatin, a natural anti-neoplastic reagent that activates PKC, induces YAP1/p73-mediated apoptosis in cancer cells. Bryostatin reverses malignant transformation caused by the depletion of LATS kinases. Therefore, bryostatin and other reagents that activate PKC are expected to control cancers with the dysfunction of the Hippo pathway.
Assuntos
Transdução de Sinais , Humanos , Briostatinas , Fosfoproteínas/metabolismo , Proteína Quinase C/metabolismo , Serina , Transdução de Sinais/genética , Proteínas de Sinalização YAPRESUMO
While combination antiretroviral therapy maintains undetectable viremia in people living with HIV (PLWH), a lifelong treatment is necessary to prevent viremic rebound after therapy cessation. This rebound seemed mainly caused by long-lived HIV-1 latently infected cells reverting to a viral productive status. Reversing latency and elimination of these cells by the so-called shock-and-kill strategy is one of the main investigated leads to achieve an HIV-1 cure. Small molecules referred to as latency reversal agents (LRAs) proved to efficiently reactivate latent CD4+ T cells. However, the LRA impact on de novo infection or HIV-1 production in productively infected macrophages remains elusive. Nontoxic doses of bryostatin-1, JQ1, and romidepsin were investigated in human monocyte-derived macrophages (MDMs). Treatment with bryostatin-1 or romidepsin resulted in a downregulation of CD4 and CCR5 receptors, respectively, accompanied by a reduction of R5 tropic virus infection. HIV-1 replication was mainly regulated by receptor modulation for bryostatin-1, while romidepsin effects rely on upregulation of SAMHD1 activity. LRA stimulation of chronically infected cells did not enhance HIV-1 production or gene expression. Surprisingly, bryostatin-1 caused a major decrease in viral production. This effect was not viral strain specific but appears to occur only in myeloid cells. Bryostatin-1 treatment of infected MDMs led to decreased amounts of capsid and matrix mature proteins with little to no modulation of precursors. Our observations revealed that bryostatin-1-treated myeloid and CD4+ T cells respond differently upon HIV-1 infection. Therefore, additional studies are warranted to more fully assess the efficiency of HIV-1 eradicating strategies. IMPORTANCE HIV-1 persists in a cellular latent form despite therapy that quickly propagates infection upon treatment interruption. Reversing latency would contribute to eradicate these cells, closing the gap to a cure. Macrophages are an acknowledged HIV-1 reservoir during therapy and are suspected to harbor latency establishment in vivo. However, the impact of latency reversal agents (LRAs) on HIV-1 infection and viral production in human macrophages is poorly known but nonetheless crucial to probe the safety of this strategy. In this in vitro study, we discovered encouraging antireplicative features of distinct LRAs in human macrophages. We also described a new viral production inhibition mechanism by protein kinase C agonists that is specific to myeloid cells. This study provides new insights into HIV-1 propagation restriction potentials by LRAs in human macrophages and underline the importance of assessing latency reversal strategy on all HIV-1-targeted cells.
Assuntos
Fármacos Anti-HIV/farmacologia , Briostatinas/farmacologia , HIV-1/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Depsipeptídeos/farmacologia , Diterpenos/farmacologia , Proteína do Núcleo p24 do HIV/metabolismo , Humanos , Macrófagos/metabolismo , Macrófagos/virologia , Receptores CCR5/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
Latent HIV reservoirs persist in people living with HIV despite effective antiretroviral therapy and contribute to rebound viremia upon treatment interruption. Macrophages are an important reservoir cell type, but analysis of agents that modulate latency in macrophages is limited by lack of appropriate in vitro models. We therefore generated an experimental system to investigate this by purifying nonproductively infected human monocyte-derived macrophages (MDM) following in vitro infection with an M-tropic enhanced green fluorescent protein reporter HIV clone and quantified activation of HIV transcription using live-cell fluorescence microscopy. The proportion of HIV-infected MDM was quantified by qPCR detection of HIV DNA, and GFP expression was validated as a marker of productive HIV infection by colabeling of HIV Gag protein. HIV transcription spontaneously reactivated in latently infected MDM at a rate of 0.22% ± 0.04% cells per day (mean ± the standard error of the mean, n = 10 independent donors), producing infectious virions able to infect heterologous T cells in coculture experiments, and both T cells and TZM-bl cells in a cell-free infection system using MDM culture supernatants. Polarization to an M1 phenotype with gamma interferon plus tumor necrosis factor resulted in a 2.3-fold decrease in initial HIV infection of MDM (P < 0.001, n = 8) and a 1.4-fold decrease in spontaneous reactivation (P = 0.025, n = 6), whereas M2 polarization using interleukin-4 prior to infection led to a 1.6-fold decrease in HIV infectivity (P = 0.028, n = 8) but a 2.0-fold increase in the rate of HIV reactivation in latently infected MDM (P = 0.023, n = 6). The latency reversing agents bryostatin and vorinostat, but not panobinostat, significantly induced HIV reactivation in latently infected MDM (P = 0.031 and P = 0.038, respectively, n = 6). IMPORTANCE Agents which modulate latent HIV reservoirs in infected cells are of considerable interest to HIV cure strategies. The present study characterizes a robust, reproducible model enabling quantification of HIV reactivation in primary HIV-infected human MDM which is relatively insensitive to the monocyte donor source and hence suitable for evaluating latency modifiers in MDM. The rate of initial viral infection was greater than the rate of HIV reactivation, suggesting that different mechanisms regulate these processes. HIV reactivation was sensitive to macrophage polarization, suggesting that cellular and tissue environments influence HIV reactivation in different macrophage populations. Importantly, latently infected MDM showed different susceptibilities to certain latency-reversing agents known to be effective in T cells, indicating that dedicated strategies may be required to target latently infected macrophage populations in vivo.
Assuntos
HIV-1/genética , HIV-1/fisiologia , Macrófagos/virologia , Transcrição Gênica , Ativação Viral , Briostatinas/farmacologia , Citocinas/farmacologia , HIV-1/efeitos dos fármacos , Humanos , Panobinostat/farmacologia , Linfócitos T/virologia , Latência Viral , Replicação Viral , Vorinostat/farmacologiaRESUMO
Activation of CXCR2 by chemokines such as CXCL1 and CXCL2 increases aggressiveness of breast cancer, inducing chemoresistance, hence CXCR2 antagonists are in clinical trials. We previously reported that inhibition of CXCR2 increases MIP-2 (CXCL2), which may inhibit anti-tumoral effects of CXCR2 antagonists. This seems to be due to inhibition of protein kinase C (PKC) by CXCR2 antagonist since specific inhibitor of PKC also enhances MIP-2 secretion. We here examined whether CXCR2 inhibitor also increases KC (CXCL1) secretion, ligand for CXCR2 involved in metastasis and PKC activators can prevent increases in chemokine secretion. We used SB 225002, which is a specific CXCR2 antagonist. The effects of PKC activators that have documented anti-tumoral effects and activates multiple isozymes of PKC such as Ingenol-3-angelate (I3A) and bryostatin-1 were examined here. In addition, FR236924, PKCε selective and 7α-acetoxy-6ß-benzoyloxy-12-O-benzoylroyleanone (Roy-Bz), PKCδ selective activators were also tested. The effects of activators were determined using brain metastatic (4TBM) and heart metastatic (4THM) subset of 4T1 breast carcinoma cells because these aggressive carcinoma cells with cancer stem cell features secrete high levels of KC and MIP-2. Inhibition of CXCR-2 activity increased KC (CXCL1) secretion. PKC activators prevented SB225002-induced increases in KC and MIP-2 secretion. Different activators/modulators induce differential changes in basal and SB225002-induced chemokine secretion as well as cell proliferation and the activators that act on PKCδ and/or PKCε such as bryostatin 1, FR236924 and Roy-Bz are the most effective. These activators alone also decrease cell proliferation or chemokine secretion or both. Given the role of KC and MIP-2 in drug resistance including chemotherapeutics, activators of PKCε and PKCδ may prevent emerging of resistance to CXCR2 inhibitors as well as other chemotherapeutics.
Assuntos
Quimiocinas/metabolismo , Ativadores de Enzimas/farmacologia , Neoplasias Mamárias Animais/enzimologia , Neoplasias Mamárias Animais/patologia , Proteína Quinase C-delta/metabolismo , Proteína Quinase C-épsilon/metabolismo , Receptores de Interleucina-8B/antagonistas & inibidores , Alcanos/farmacologia , Animais , Briostatinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimiocina CXCL2/metabolismo , Ciclopropanos/farmacologia , Diterpenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Indóis/farmacologia , Camundongos Endogâmicos BALB C , Compostos de Fenilureia/farmacologia , Receptores de Interleucina-8B/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
AIDS is a pandemic disease caused by HIV that affects 37 million people worldwide. Current antiretroviral therapy slows disease progression but does not eliminate latently infected cells, which resupply active virus, thus necessitating lifelong treatment with associated compliance, cost, and chemoexposure issues. Latency-reversing agents (LRAs) activate these cells, allowing for their potential clearance, thus presenting a strategy to eradicate the infection. Protein kinase C (PKC) modulators-including prostratin, ingenol esters, bryostatin, and their analogs-are potent LRAs in various stages of development for several clinical indications. While LRAs are promising, a major challenge associated with their clinical use is sustaining therapeutically meaningful levels of the active agent while minimizing side effects. Here we describe a strategy to address this problem based on LRA prodrugs, designed for controllable release of the active LRA after a single injection. As intended, these prodrugs exhibit comparable or superior in vitro activity relative to the parent compounds. Selected compounds induced higher in vivo expression of CD69, an activation biomarker, and, by releasing free agent over time, significantly improved tolerability when compared to the parent LRAs. More generally, selected prodrugs of PKC modulators avoid the bolus toxicities of the parent drug and exhibit greater efficacy and expanded tolerability, thereby addressing a longstanding objective for many clinical applications.
Assuntos
Fármacos Anti-HIV/farmacologia , Briostatinas/farmacologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Pró-Fármacos/farmacologia , Proteína Quinase C/metabolismo , Latência Viral/efeitos dos fármacos , Animais , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/uso terapêutico , Briostatinas/síntese química , Briostatinas/uso terapêutico , Linhagem Celular Tumoral , Células Cultivadas , Diterpenos/química , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ésteres de Forbol/química , Pró-Fármacos/síntese química , Pró-Fármacos/uso terapêutico , Proteína Quinase C/efeitos dos fármacosRESUMO
Latent HIV reservoirs are the main obstacle to eradicate HIV infection. One strategy proposes to eliminate these viral reservoirs by pharmacologically reactivating the latently infected T cells. We show here that a 4-deoxyphorbol ester derivative isolated from Euphorbia amygdaloides ssp. semiperfoliata, 4ß-dPE A, reactivates HIV-1 from latency and could potentially contribute to decrease the viral reservoir. 4ß-dPE A shows two effects in the HIV replication cycle, infection inhibition and HIV transactivation, similarly to other phorboids PKC agonists such PMA and prostratin and to other diterpene esters such SJ23B. Our data suggest 4ß-dPE A is non-tumorigenic, unlike the related compound PMA. As the compounds are highly similar, the lack of tumorigenicity by 4ß-dPE A could be due to the lack of a long side lipophilic chain that is present in PMA. 4ß-dPE activates HIV transcription at nanomolar concentrations, lower than the concentration needed by other latency reversing agents (LRAs) such as prostratin and similar to bryostatin. PKCθ/MEK activation is required for the transcriptional activity, and thus, anti-latency activity of 4ß-dPE A. However, CD4, CXCR4 and CCR5 receptors down-regulation effect seems to be independent of PCK/MEK, suggesting the existence of at least two different targets for 4ß-dPE A. Furthermore, NF-κb transcription factor is involved in 4ß-dPE HIV reactivation, as previously shown for other PKCs agonists. We also studied the effects of 4ß-dPE A in combination with other LRAs. When 4ß-dPE A was combined with another PKC agonists such as prostratin an antagonic effect was achieved, while, when combined with an HDAC inhibitor such as vorinostat, a strong synergistic effect was obtained. Interestingly, the latency reversing effect of the combination was synergistically diminishing the EC50 value but also increasing the efficacy showed by the drugs alone. In addition, combinations of 4ß-dPE A with antiretroviral drugs as CCR5 antagonist, NRTIs, NNRTIs and PIs, showed a consistent synergistic effect, suggesting that the combination would not interefer with antiretroviral therapy (ART). Finally, 4ß-dPE A induced latent HIV reactivation in CD4 + T cells of infected patients under ART at similar levels than the tumorigenic phorbol derivative PMA, showing a clear reactivation effect. In summary, we describe here the mechanism of action of a new potent deoxyphorbol derivative as a latency reversing agent candidate to decrease the size of HIV reservoirs.
Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/metabolismo , HIV-1/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Ésteres de Forbol/farmacologia , Proteína Quinase C/metabolismo , Ativação Viral/efeitos dos fármacos , Vorinostat/farmacologia , Briostatinas/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Células Jurkat , Transdução de Sinais/efeitos dos fármacos , Latência Viral/efeitos dos fármacosRESUMO
Bryostatin 1 is a marine natural product under investigation for HIV/AIDS eradication, the treatment of neurological disorders, and enhanced CAR T/NK cell immunotherapy. Despite its promising activity, bryostatin 1 is neither evolved nor optimized for the treatment of human disease. Here we report the design, synthesis, and biological evaluation of several close-in analogs of bryostatin 1. Using a function-oriented synthesis approach, we synthesize a series of bryostatin analogs designed to maintain affinity for bryostatin's target protein kinase C (PKC) while enabling exploration of their divergent biological functions. Our late-stage diversification strategy provides efficient access to a library of bryostatin analogs, which per our design retain affinity for PKC but exhibit variable PKC translocation kinetics. We further demonstrate that select analogs potently increase cell surface expression of CD22, a promising CAR T cell target for the treatment of leukemias, highlighting the clinical potential of bryostatin analogs for enhancing targeted immunotherapies.
Assuntos
Briostatinas/biossíntese , Briostatinas/farmacologia , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Proteína Quinase C/metabolismo , Briostatinas/química , Linhagem Celular Tumoral , Humanos , Leucemia/tratamento farmacológico , Modelos Moleculares , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Linfócitos TRESUMO
Bryostatins are complex macrolactones isolated from marine organisms Bryozoan Bugula neritina. They are potent modulators of protein kinase C isozymes (PKCα: ki = 1.3-188 nM), and are one of the most extensively investigated marine natural products in clinical trials. Although ~21 natural bryostatins have been isolated, however only bryostatin-1 (1) has received much interest among medicinal chemists and clinicians. The structure-activity relationship of bryostatins has been well established, with the identification of key pharmacophoric features important for PKC modulation. The low natural abundance and the long synthetic route have prompted medicinal chemists to come-up with simplified analogs. Bryostatin skeleton comprises three pyran rings connected to each other to form a macrocyclic lactone. The simplest analog 27 contains only one pyran, which is also able to modulate the PKCα activity; however, the cyclic framework appears to be essential for the desired level of potency. Another simplified analog 17 ("picolog") exhibited potent and in-vivo efficacy against lymphoma. Bryostatin-1 (1) has shown an acceptable intravenous pharmacokinetic profile in mice and displayed promising in-vivo efficacy in mice models of various cancers and Alzheimer's disease. Bryostatin-1 was investigated in numerous Phase I/II oncology clinical trials; it has shown minimal effect as a single agent, however, provided encouraging results in combination with other chemotherapy agents. FDA has granted orphan drug status to bryostatin-1 in combination with paclitaxel for esophageal cancer. Bryostatin-1 has also received orphan drug status for fragile X syndrome. Bryostatin-1 was also investigated in clinical studies for Alzheimer's disease and HIV infection. In a nutshell, the natural as well as synthetic bryostatins have generated a strong hope to emerge as treatment for cancer along with many other diseases.
Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Briostatinas/farmacologia , Neoplasias/tratamento farmacológico , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Briostatinas/química , Briostatinas/isolamento & purificação , Briozoários/química , Humanos , Neoplasias/metabolismo , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/isolamento & purificaçãoRESUMO
The reactivation of HIV latency cell will be necessary to curing HIV infection. Although many latency-reversal agents (LRAs) have proven effective to reactivate the latency cell, there is a lack of any systematic analysis of the molecular targets of these LRAs and related pathways in the context of transcriptome. In this study, we performed an integrated analysis of the target profile of bryostatin and transcriptome of the reactivated CD4+ T cells after exposing to bryostatin. The result showed a distinct gene expression profile between latency cells and bryostatin reactivated cells. We found bryostatin can target multiple types of protein other than only protein kinase C. Functional network analysis of the target profile and differential expressed genes suggested that bryostatin may activate a few novel pathways such as pyrimidine metabolism, purine metabolism and p53 signaling pathway, besides commonly known pathways DNA replication, cell cycle and so on. The results suggest that bryostatin may reactivate the HIV-latent cells through up-regulation of pyrimidine and purine metabolism or through starting the cell-cycle arrest and apoptosis induced by up-regulation of p53 signaling pathway. Our study provides some novel insights into the role of bryostatin and its affected pathways in controlling HIV latency and reactivation.
Assuntos
Briostatinas/farmacologia , Infecções por HIV/patologia , Transcriptoma/efeitos dos fármacos , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Purinas/metabolismo , Pirimidinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Latência ViralRESUMO
Bryostatins are a class of naturally occurring macrocyclic lactones with a unique fast developing portfolio of clinical applications, including treatment of AIDS, Alzheimer's disease, and cancer. This comprehensive account summarizes the recent progress (2014-present) in the development of bryostatins, including their total synthesis and biomedical applications. An emphasis is placed on the discussion of bryostatin 1, the most-studied analogue to date. This review highlights the synthetic and biological challenges of bryostatins and provides an outlook on their future development.
Assuntos
Antineoplásicos/química , Briostatinas/síntese química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Briostatinas/farmacologia , Briostatinas/uso terapêutico , Senescência Celular/efeitos dos fármacos , Doenças do Sistema Nervoso Central/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Humanos , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismoRESUMO
Recent advances in sampling and novel techniques in drug synthesis and isolation have promoted the discovery of anticancer agents from marine organisms to combat this major threat to public health worldwide. Bryozoans, which are filter-feeding, aquatic invertebrates often characterized by a calcified skeleton, are an excellent source of pharmacologically interesting compounds including well-known chemical classes such as alkaloids and polyketides. This review covers the literature for secondary metabolites isolated from marine cheilostome and ctenostome bryozoans that have shown potential as cancer drugs. Moreover, we highlight examples such as bryostatins, the most known class of marine-derived compounds from this animal phylum, which are advancing through anticancer clinical trials due to their low toxicity and antineoplastic activity. The bryozoan antitumor compounds discovered until now show a wide range of chemical diversity and biological activities. Therefore, more research focusing on the isolation of secondary metabolites with potential anticancer properties from bryozoans and other overlooked taxa covering wider geographic areas is needed for an efficient bioprospecting of natural products.
Assuntos
Antineoplásicos/química , Briozoários/química , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Organismos Aquáticos/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Briostatinas/química , Briostatinas/farmacologia , Briostatinas/uso terapêutico , Humanos , Invertebrados/químicaRESUMO
Bryostatin-1 (Bry-1) has been proven to be effective and safe in clinical trials of a variety of immune-related diseases. However, little is known about its effect on Crohn's disease (CD). We aimed to investigate the impact of Bry-1 on CD-like colitis and determine the mechanism underlying this effect. In the present study, 15-week-old male Il-10-/- mice with spontaneous colitis were divided into positive control and Bry-1-treated (Bry-1, 30 µg/kg every other day, injected intraperitoneally for 4 weeks) groups. Age-matched, male wild-type (WT) mice were used as a negative control. The effects of Bry-1 on colitis, intestinal barrier function and T cell responses as well as the potential regulatory mechanisms were evaluated. We found that the systemic delivery of Bry-1 significantly ameliorated colitis in Il-10-/- mice, as demonstrated by decreases in the disease activity index (DAI), inflammatory score and proinflammatory mediator levels. The protective effects of Bry-1 on CD-like colitis included the maintenance of intestinal barrier integrity and the helper T cell (Th)/regulatory T cell (Treg) balance. These effects of Bry-1 may act in part through nuclear factor erythroid 2-related factor 2 (Nrf2) signalling activation and STAT3/4 signalling inhibition. The protective effect of Bry-1 on CD-like colitis suggests Bry-1 has therapeutic potential in human CD, particularly given the established clinical safety of Bry-1.
Assuntos
Briostatinas/uso terapêutico , Colite/tratamento farmacológico , Colite/imunologia , Interleucina-10/deficiência , Intestinos/imunologia , Intestinos/patologia , Animais , Apoptose/efeitos dos fármacos , Briostatinas/farmacologia , Colite/patologia , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/metabolismo , Interleucina-10/metabolismo , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Permeabilidade , Transdução de Sinais/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/ultraestruturaRESUMO
Bryostatin-1, a macrolide lactone derived from marine organism Bugula neritina, has been shown to inhibit carcinogenesis in several prospective clinical trials. In the current study, the therapeutic potential of bryostatin-1 in inhibiting proliferation of hepatocarcinoma was evaluated by in vitro and in vivo studies. The mechanisms of action of bryostatin-1 were predicted by in silico assay and further validated by surface plasmon resonance and western blot assay. Our results show that bryostatin-1 (100, 200â¯nM) treatment can suppress cell proliferation and induce G1 cell cycle arrest in PLC/PRF/5 and SMCC7721â¯cell. We also found a significant inhibitory action of bryostatin-1 (100, 200â¯nM) on CyclinD1 activity in PLC/PRF/5â¯cells, and bryostatin-1 can promote ubiquitination-dependent protein degradation of CyclinD1 in PLC/PRF/5â¯cells. Western blot results confirmed that the active form phospho-GSK3ß Tyr216 expression was increased significantly after bryostatin-1 treatment. Activation of GSK3ß might be responsible for bryostatin-1 induced cyclinD1 degradation and cell cycle arrest. Taken together, bryostatin-1 may inhibit HCC cells proliferation by promoting cyclinD1 proteolysis and inducing cell cycle arrest.
Assuntos
Antineoplásicos/uso terapêutico , Briostatinas/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Briostatinas/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos BALB C , Camundongos NusRESUMO
Bugula neritina is a common invasive cosmopolitan bryozoan that harbors (like many sessile marine invertebrates) a symbiotic bacterial (SB) community. Among the SB of B. neritina, "Candidatus Endobugula sertula" continues to receive the greatest attention, because it is the source of bryostatins. The bryostatins are potent bioactive polyketides, which have been investigated for their therapeutic potential to treat various cancers, Alzheimer's disease, and AIDS. In this study, we compare the metagenomics sequences for the 16S ribosomal RNA gene of the SB communities from different geographic and life cycle samples of Chinese B. neritina. Using a variety of approaches for estimating alpha/beta diversity and taxonomic abundance, we find that the SB communities vary geographically with invertebrate and fish mariculture and with latitude and environmental temperature. During the B. neritina life cycle, we find that the diversity and taxonomic abundances of the SB communities change with the onset of host metamorphosis, filter feeding, colony formation, reproduction, and increased bryostatin production. "Ca. Endobugula sertula" is confirmed as the symbiont of the Chinese "Ca. Endobugula"/B. neritina symbiosis. Our study extends our knowledge about B. neritina symbiosis from the New to the Old World and offers new insights into the environmental and life cycle factors that can influence its SB communities, "Ca. Endobugula," and bryostatins more globally.