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We have previously reported two single-agent phase I trials, evaluating the dose or schedule, of a DNA vaccine (pTVG-HP) encoding prostatic acid phosphatase (PAP) administered with GM-CSF as the adjuvant. These were in patients with PSA-recurrent, radiographically non-metastatic, prostate cancer (PCa). We report here the long-term safety and overall survival of these patients. Specifically, 22 patients with non-metastatic, castration-sensitive PCa (nmCSPC) were treated with pTVG-HP, 100-1500 µg, administered over 12 weeks and followed for 15 y. 17 patients with non-metastatic castration-resistant PCa (nmCRPC) were treated with 100 µg pTVG-HP with different schedules of administration over 1 y and followed for 5 y. No adverse events were detected in long-term follow-up from either trial that were deemed possibly related to vaccination. Patients with nmCSPC had a median overall survival of 12.3 y, with 5/22 (23%) alive at 15 y. 8/22 (36%) died due to prostate cancer with a median survival of 11.0 y, and 9/22 (41%) died of other causes. Patients with nmCRPC had a median overall survival of 4.5 y, with 8/17 (47%) alive at 5 y. The presence of T-cells specific for the PAP target antigen was detectable in 6/10 (60%) individuals with nmCSPC, and 3/5 (60%) individuals with nmCRPC, many years after immunization. The detection of immune responses to the vaccine target years after immunization suggests durable immunity can be elicited in patients using a DNA vaccine encoding a tumor-associated antigen.Trial Registration: NCT00582140 and NCT00849121.
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Vacunas contra el Cáncer , Antígeno Prostático Específico , Neoplasias de la Próstata , Vacunas de ADN , Humanos , Masculino , Vacunas de ADN/inmunología , Vacunas de ADN/administración & dosificación , Vacunas de ADN/efectos adversos , Antígeno Prostático Específico/inmunología , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/administración & dosificación , Anciano , Estudios de Seguimiento , Neoplasias de la Próstata/inmunología , Persona de Mediana Edad , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Resultado del Tratamiento , Anciano de 80 o más Años , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Recurrencia Local de Neoplasia , Análisis de Supervivencia , Fosfatasa Ácida , Proteínas Tirosina Fosfatasas/inmunologíaRESUMEN
We report a rare case of a 59-year-old male with a history of metastatic prostate cancer presenting with acute onset dyspnea due to extensive bilateral pleural effusions. This case highlights the rarity of metastatic prostate cancer with pleural involvement and underscores the importance of accurate diagnosis using cytopathology and immunohistochemical staining.
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This study assesses the in vitro release of tenofovir (TFV)-loaded triphosphate (TPP) cross-linked chitosan nanoparticles (NPs) catalyzed by human prostatic acid phosphatase (hPAP) for 24 h. The physico-chemical characterization of the NPs included particle mean diameter (PMD), zeta potential (ζ), percent drug encapsulation efficiency (% EE), Fourier transform infra-red (FTIR) spectroscopy, powder X-ray diffractometry analysis (PXRD), and drug release kinetics. The first-order rate constant (k) and activation energy (Ea) of the cross-link (TPP) are determined by the integrated rate law and Arrhenius's equations. The hPAP Michaelis-Menten constant (Km) is determined by the Lineweaver-Burk's equation. The NP's safety profile is evaluated on vaginal epithelial cells (VK2/E6E7). The lyophilized drug-loaded NPs' PMD, ζ, and PDI are 149.97 nm, 4.4 mV, and 0.3, respectively. The % EE after lyophilization is 93.7 ± 4.4%. These NPs released drug at faster rate (63% of TFV within 6 h) under the enzyme's influence. The similarity and difference factors of drug release profiles (absence vs presence of hPAP) are 56.5 and 40.3, respectively. The hPAP's Km value of 0.019 mM suggests it has a good affinity for TPP at physiological pH ~ 7.4. The enhanced hydrolysis of TPP or degradation of chitosan NPs is fundamentally due to a decrease of TPP's activation energy by hPAP. In fact, the Ea value is 22.50 ± 3.06 kJ/mol or 16.33 ± 0.62 kJ/mol in the absence or presence of hPAP, respectively. The NPs are non-cytotoxic to the treated vaginal cell line. These hPAP-responsive NPs are promising topical nanomicrobicides for HIV/AIDS prevention.
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Quitosano , Nanopartículas , Femenino , Humanos , Tenofovir , Quitosano/química , Vagina , Nanopartículas/química , Fosfatasa Ácida , Tamaño de la Partícula , Portadores de Fármacos/químicaRESUMEN
KEY MESSAGE: PAP-FcK and PSA-FcK prostate cancer antigenic proteins transiently co-expressed in plant induce their specific humoral immune responses in mice. Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) have been considered as immunotherapeutic antigens for prostate cancer. The use of a single antigenic agent is unlikely to be effective in eliciting immunotherapeutic responses due to the heterogeneous and multifocal nature of prostate cancer. Thus, multiple antigens have been combined to enhance their anti-cancer effects. In the current study, PSA and PAP were fused to the crystallizable region (Fc region) of immunoglobulin G1 and tagged with KDEL, the endoplasmic reticulum (ER) retention signal motif, to generate PSA-FcK and PAP-FcK, respectively, and were transiently co-expressed in Nicotiana benthamiana. Western blot analysis confirmed the co-expression of PSA-FcK and PAP-FcK (PSA-FcK + PAP-FcK) with a 1:3 ratios in the co-infiltrated plants. PSA-FcK, PAP-FcK, and PSA-FcK + PAP-FcK proteins were successfully purified from N. benthamiana by protein A affinity chromatography. ELISA showed that anti-PAP and anti-PSA antibodies successfully detected PAP-FcK and PSA-FcK, respectively, and both detected PSA-FcK + PAP-FcK. Surface plasmon resonance (SPR) analysis confirmed the binding affinity of the plant-derived Fc fusion proteins to FcγRI/CD64. Furthermore, we also confirmed that mice injected with PSA-FcK + PAP-FcK produced both PSA- and PAP-specific IgGs, demonstrating their immunogenicity. This study suggested that the transient plant expression system can be applied to produce the dual-antigen Fc fusion protein (PSA-FcK + PAP-FcK) for prostate cancer immunotherapy.
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Vacunas contra el Cáncer , Neoplasias de la Próstata , Animales , Humanos , Masculino , Ratones , Fosfatasa Ácida/genética , Fosfatasa Ácida/metabolismo , Vacunas contra el Cáncer/uso terapéutico , Inmunidad , Próstata/metabolismo , Antígeno Prostático Específico , Neoplasias de la Próstata/terapiaRESUMEN
Semen prostatic acid phosphatase (PAP) has been proposed as an endogenous ligand for dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN), which plays a critical immuno-modulating role in maintaining homeostasis in the female reproductive tracts. In the current study, we assumed that semen PAP bears a set of fucosylated and mannosylated glycans, which may mediate the efficient binding of PAP to DC-SIGN. To investigate this hypothesis, we developed ELISA assays using Galanthus nivalis and Lotus tetragonolobus lectins capable of binding mannose-containing glycans or LewisX and LewisY motifs, respectively. In our assay with Galanthus nivalis, we detected that the relative reactivity of PAP mannose-presenting glycans in the normozoospermic idiopathic group was significantly higher than in the asthenozoospermic, oligozoospermic and oligoasthenozoospermic groups. Simultaneously, we observed slight differences in the relative reactivities of PAP glycans with Lotus tetragonolobus lectin among groups of patients with abnormal semen parameters. Subsequently, we examined whether DC-SIGN interacts with seminal plasma PAP glycans, and we detected a significantly higher relative reactivity in the normozoospermic group compared to the oligozoospermic group. Finally, we concluded that the significantly aberrant abundance of mannosylated functional groups of PAP among patients with semen disorders can suggest that PAP may thereby be engaged in modulating the immune response and promoting a tolerogenic response to male antigens in the female reproductive system.
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Fosfatasa Ácida , Moléculas de Adhesión Celular , Infertilidad , Lectinas Tipo C , Receptores de Superficie Celular , Semen , Humanos , Femenino , Masculino , Ligandos , Manosa , PolisacáridosRESUMEN
Prostatic acid phosphatase (PAP) exists as two splice variants, secreted PAP and transmembrane PAP, the latter of which is implicated in antinociceptive signaling in dorsal root ganglia. However, PAP is predominantly expressed in the prostate gland and the physiological role of seminal PAP, first identified in 1938, is largely unknown. Here, the author proposes that PAP, following ejaculation, functions to hydrolyze phosphocholine (PC) in seminal fluid and generate choline, which is imported by sperm via a choline transporter and converted to acetylcholine (ACh) by choline acetyltransferase. Auto- and paracrine cholinergic signaling, or choline directly, may subsequently stimulate sperm motility via α7 nicotinic ACh receptors (nAChRs) and contractility of the female reproductive tract through muscarinic ACh receptors (mAChRs). Consistent with a role of PAP in cholinergic signaling, 1) seminal vesicles secrete PC, 2) the prostate gland secretes PAP, 3) PAP specifically catalyzes the hydrolysis of PC into inorganic phosphate and choline, 4) seminal choline levels increase post-ejaculation, 5) pharmacological inhibition of choline acetyltransferase inhibits sperm motility, 6) inhibition or genetic deletion of α7 nAChRs impairs sperm motility, and 7) mAChRs are expressed in the uterus and oviduct (fallopian tube). Notably, PAP does not degrade glycerophosphocholine (GPC), the predominant choline source in the semen of rats and other mammals. Instead, uterine GPC phosphodiesterases may liberate choline from seminal GPC. In summary, the author deduces that PAP in humans, and uterine GPC phosphodiesterases in other mammals, function to generate choline for sperm cholinergic signaling, which promotes sperm motility and possibly contractility of the female reproductive tract.
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Tissue-specific antigens can serve as targets for adoptive T cell transfer-based cancer immunotherapy. Recognition of tumor by T cells is mediated by interaction between peptide-major histocompatibility complexes (pMHCs) and T cell receptors (TCRs). Revealing the identity of peptides bound to MHC is critical in discovering cognate TCRs and predicting potential toxicity. We performed multimodal immunopeptidomic analyses for human prostatic acid phosphatase (PAP), a well-recognized tissue antigen. Three physical methods, including mild acid elution, coimmunoprecipitation, and secreted MHC precipitation, were used to capture a thorough signature of PAP on HLA-A*02:01. Eleven PAP peptides that are potentially A*02:01-restricted were identified, including five predicted strong binders by NetMHCpan 4.0. Peripheral blood mononuclear cells (PBMCs) from more than 20 healthy donors were screened with the PAP peptides. Seven cognate TCRs were isolated which can recognize three distinct epitopes when expressed in PBMCs. One TCR shows reactivity toward cell lines expressing both full-length PAP and HLA-A*02:01. Our results show that a combined multimodal immunopeptidomic approach is productive in revealing target peptides and defining the cloned TCR sequences reactive with prostatic acid phosphatase epitopes.
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Fosfatasa Ácida , Antígenos de Neoplasias , Receptores de Antígenos de Linfocitos T , Fosfatasa Ácida/metabolismo , Antígenos de Neoplasias/metabolismo , Epítopos , Antígenos HLA-A/metabolismo , Antígeno HLA-A2 , Humanos , Leucocitos Mononucleares , Neoplasias/inmunología , Péptidos , Receptores de Antígenos de Linfocitos T/metabolismoRESUMEN
BACKGROUND: Current treatments for castrate (hormone)-resistant prostate cancer (CRPC) remain limited and are not curative, with a median survival from diagnosis of 23 months. The PAP-specific Sipuleucel-T vaccine, which was approved by the FDA in 2010, increases the Overall Survival (OS) by 4 months, but is extremely expensive. We have previously shown that a 15 amino accid (AA) PAP sequence-derived peptide could induce strong immune responses and delay the growth of murine TRAMP-C1 prostate tumors. We have now substituted one amino acid and elongated the sequence to include epitopes predicted to bind to several additional HLA haplotypes. Herein, we present the immunological properties of this 42mer-mutated PAP-derived sequence (MutPAP42mer). METHODS: The presence of PAP-135-143 epitope-specific CD8+ T cells in the blood of patients with prostate cancer (PCa) was assessed by flow cytometry using Dextramer™ technology. HHDII/DR1 transgenic mice were immunized with mutated and non-mutated PAP-derived 42mer peptides in the presence of CAF®09 or CpG ODN1826 (TLR-9 agonist) adjuvants. Vaccine-induced immune responses were measured by assessing the proportion and functionality of splenic PAP-specific T cells in vitro. RESULTS: PAP-135-143 epitope-specific CD8+ T cells were detected in the blood of patients with PCa and stimulation of PBMCs from patients with PCa with mutPAP42mer enhanced their capacity to kill human LNCaP PCa target cells expressing PAP. The MutPAP42mer peptide was significantly more immunogenic in HHDII/DR1 mice than the wild type sequence, and immunogenicity was further enhanced when combined with the CAF®09 adjuvant. The vaccine induced secretory (IFNγ and TNFα) and cytotoxic CD8+ T cells and effector memory splenic T cells. CONCLUSIONS: The periphery of patients with PCa exhibits immune responsiveness to the MutPAP42mer peptide and immunization of mice induces/expands T cell-driven, wild-type PAP immunity, and therefore, has the potential to drive protective anti-tumor immunity in patients with PCa.
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The role of human prostatic acid phosphatase (PAcP, P15309|PPAP_HUMAN) in prostate cancer was investigated using a new proteomics tool termed signal sequence swapping (replacement of domains from the native cleaved amino terminal signal sequence of secretory/membrane proteins with corresponding regions of functionally distinct signal sequence subtypes). This manipulation preferentially redirects proteins to different pathways of biogenesis at the endoplasmic reticulum (ER), magnifying normally difficult to detect subsets of the protein of interest. For PAcP, this technique reveals three forms identical in amino acid sequence but profoundly different in physiological functions, subcellular location, and biochemical properties. These three forms of PAcP can also occur with the wildtype PAcP signal sequence. Clinical specimens from patients with prostate cancer demonstrate that one form, termed PLPAcP, correlates with early prostate cancer. These findings confirm the analytical power of this method, implicate PLPAcP in prostate cancer pathogenesis, and suggest novel anticancer therapeutic strategies.
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Fosfatasa Ácida/metabolismo , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Retículo Endoplásmico/enzimología , Neoplasias de la Próstata/enzimología , Fosfatasa Ácida/genética , Andrógenos/farmacología , Antineoplásicos Hormonales/farmacología , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Detección Precoz del Cáncer , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/genética , Retículo Endoplásmico/patología , Humanos , Isoenzimas , Masculino , Valor Predictivo de las Pruebas , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Conformación Proteica , Relación Estructura-ActividadRESUMEN
The role of human prostatic acid phosphatase (PAcP, P15309|PPAP_HUMAN) in prostate cancer was investigated using a new proteomic tool termed signal sequence swapping (replacement of domains from the native cleaved amino terminal signal sequence of secretory/membrane proteins with corresponding regions of functionally distinct signal sequence subtypes). This manipulation preferentially redirects proteins to different pathways of biogenesis at the endoplasmic reticulum, magnifying normally difficult to detect subsets of the protein of interest. For PAcP this technique reveals three forms identical in amino acid sequence but profoundly different in physiological functions, subcellular location, and biochemical properties. These three forms of PAcP can also occur with the wild-type PAcP signal sequence. Clinical specimens from patients with prostate cancer demonstrate that one form, termed PLPAcP, correlates with early prostate cancer. These findings confirm the analytical power of this method, implicate PLPAcP in prostate cancer pathogenesis, and suggest novel anticancer therapeutic strategies.
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Transient receptor potential vanilloid subtype 1 (TRPV1) is a polymodal nociceptor that monitors noxious thermal sensations. Few studies have addressed the role of TRPV1 in mechanical allodynia in small-fiber neuropathy (SFN) caused by sensory nerve damage. Accordingly, this article reviews the putative mechanisms of TRPV1 depletion that mediates mechanical allodynia in SFN. The intraepidermal nerve fibers (IENFs) degeneration and sensory neuronal injury are the primary characteristics of SFN. Intraepidermal nerve fibers are mainly C-polymodal nociceptors and Aδ-fibers, which mediated allodynic pain after neuronal sensitization. TRPV1 depletion by highly potent neurotoxins induces the upregulation of activating transcription factor 3 and IENFs degeneration which mimics SFN. TRPV1 is predominately expressed by the peptidergic than nonpeptidergic nociceptors, and these neurochemical discrepancies provided the basis of the distinct pathways of thermal analgesia and mechanical allodynia. The depletion of peptidergic nociceptors and their IENFs cause thermal analgesia and sensitized nonpeptidergic nociceptors respond to mechanical allodynia. These distinct pathways of noxious stimuli suggested determined by the neurochemical-dependent neurotrophin cognate receptors such as TrkA and Ret receptors. The neurogenic inflammation after TRPV1 depletion also sensitized Ret receptors which results in mechanical allodynia. The activation of spinal TRPV1(+) neurons may contribute to mechanical allodynia. Also, an imbalance in adenosinergic analgesic signaling in sensory neurons such as the downregulation of prostatic acid phosphatase and adenosine A1 receptors, which colocalized with TRPV1 as a membrane microdomain also correlated with the development of mechanical allodynia. Collectively, TRPV1 depletion-induced mechanical allodynia involves a complicated cascade of cellular signaling alterations.
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PURPOSE OF REVIEW: Despite significant progress, patients with metastatic prostate cancer continue to have poor prognosis. Immunotherapy has revolutionized cancer care for many tumor types but has a limited role in the treatment of prostate cancer. This review discusses the promise of immunotherapy in prostate cancer treatment with an emphasis on emerging therapeutic targets. RECENT FINDINGS: Most prostate tumors have low tumor mutational burden and lack immunogenicity, representing significant hurdles to induction of anti-tumor immunity. However, recent research centered on deciphering key mechanisms of immune resistance in the prostate tumor microenvironment has led to the discovery of a range of new treatment targets. These discoveries are currently being translated into innovative immunotherapy clinical trials for patients with prostate cancer. Recent progress includes early evidence of activity for these novel approaches and the identification of potential predictive biomarkers of response. Novel treatment strategies using new antigen-directed therapies, drugs targeting the immunosuppressive tumor microenvironment, and combination immunotherapy therapies show great potential and are currently in clinical development. In addition, a deeper understanding of predictors of response and resistance to immunotherapy in prostate cancer is allowing for a more personalized approach to therapy.
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Vacunas contra el Cáncer/uso terapéutico , Inmunoterapia/métodos , Neoplasias de la Próstata/terapia , Extractos de Tejidos/uso terapéutico , Ensayos Clínicos como Asunto , Humanos , Masculino , Neoplasias de la Próstata/patología , Microambiente TumoralRESUMEN
OBJECTIVES: NKX3.1, a transcription factor related to androgen expression, has recently been introduced as a diagnostic marker of prostate adenocarcinoma. Salivary duct carcinoma (SDC) is typically positive for androgen receptor (AR). Therefore, we hypothesized that NKX3.1 is a new immunohistochemical marker for SDC and aimed to investigate whether NKX3.1 staining in combination with other immunomarkers of prostate carcinoma could have a diagnostic or prognostic value in SDC. METHODS: Materials obtained from 42 resected SDCs were examined by immunohistochemistry using antibodies against AR, NKX3.1, α-methylacyl-CoA racemase (AMACR), prostatic acid phosphatase (PAP), and prostate-specific antigen (PSA). RESULTS: In immunoreactivity among SDC cases, 81.0, 35.7, 58.5, 33.3, and 0% were positive for AR, NKX3.1, AMACR, PAP, and PSA, respectively. AMACR and PAP immunoreactivity rates were higher in recurrence cases than in cases with no recurrence. CONCLUSIONS: NKX3.1 expression is useful for SDC diagnosis, but decreased NKX3.1 expression was not correlated with SDC progression. The immunoreactivity of AMACR and PAP could be useful for assessing prognosis in SDC, but immunohistochemical staining of prostate-specific markers should be interpreted with caution when determining whether a metastatic tumor is of prostate origin, especially when patients have a history of SDC.
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Proteínas de Homeodominio/genética , Conductos Salivales/patología , Neoplasias de las Glándulas Salivales/diagnóstico , Factores de Transcripción/genética , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pronóstico , Antígeno Prostático Específico , Neoplasias de la Próstata/patología , Neoplasias de las Glándulas Salivales/secundarioRESUMEN
BACKGROUND: We previously found that PD-L1 expression is increased on tumor cells following vaccination treatments that lead to increased tumor-specific T cells that secrete IFNγ. Indoleamine 2,3-dioxygenase (IDO) is another IFNγ inducible gene that has potent immunosuppressive effects. There have been reports of IDO expression in prostate cancer; however, it is unknown whether IDO expression might similarly increase in prostate tumors following T-cell-based immunotherapy. METHODS: Blood samples from normal male blood donors (n = 12) and patients with different stages of prostate cancer (n = 89), including patients with metastatic, castration-resistant prostate cancer treated with a DNA vaccine and/or pembrolizumab, were evaluated for IDO activity by kynurenine and tryptophan levels. Metastatic tissue biopsies obtained pre- and post-treatments were evaluated for IDO expression. IDO suppression of vaccine-induced T-cell function was assessed by ELISPOT. RESULTS: Overall, IDO activity was increased in patients with more advanced prostate cancer. This activity, and IDO expression as detected immunohistochemically, increased following treatment with either a DNA vaccine encoding the prostatic acid phosphatase (PAP) tumor antigen or PD-1 blockade with pembrolizumab. Increased IDO activity after treatment was associated with the absence of clinical effect, as assessed by lack of PSA decline following treatment. Increased antigen-specific T-cell response, as measured by IFNγ release, to the vaccine target antigen was detected following in vitro stimulation of peripheral blood cells with 1-methyltryptophan. CONCLUSIONS: These findings suggest that IDO expression is a mechanism of immune evasion used by prostate cancer and that future clinical trials using T-cell-based immune strategies might best include IDO inhibition.
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Vacunas contra el Cáncer/administración & dosificación , Inmunoterapia , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Recurrencia Local de Neoplasia/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Neoplasias de la Próstata/tratamiento farmacológico , Linfocitos T/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Pronóstico , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Linfocitos T/efectos de los fármacosRESUMEN
Prostate cancer (PCa) is one of the most common cancer in men. Although hormone-sensitive PCa responds to androgen-deprivation, there are no effective therapies for castration-resistant PCa. It has been recently suggested that proton pump inhibitors (PPIs) may increase the risk of certain cancers; however, association with PCa remains elusive. Here, we evaluated the tumorigenic activities of PPIs in vitro, in PCa cell lines and epithelial cells from benign prostatic hyperplasia (BPH) and in vivo, in PCa mice xenografts. PPIs increased survival and proliferation, and inhibited apoptosis in LNCaP cells. These effects were attenuated or absent in androgen-insensitive DU-145 and PC3 cells, respectively. Specifically, omeprazole (OME) promoted cell cycle progression, increased c-Myc expression, ErbB2 activity and PSA secretion. Furthermore, OME induced the phosphorylation of MAPK-ERK1/2, PI3K/Akt and GSK-3ß, and blunted the expression and activity of cellular prostatic acid phosphatase. OME also increased survival, proliferation and PSA levels in BPH cells. In vivo, OME promoted tumor growth in mice bearing LNCaP xenografts. Our results indicate that PPIs display tumorigenic activities in PCa cells, suggesting that their long-term administration in patients should be carefully monitored.
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Fosfatasa Ácida/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neoplasias Hormono-Dependientes/enzimología , Omeprazol/toxicidad , Fosfatidilinositol 3-Quinasa/metabolismo , Neoplasias de la Próstata/enzimología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Inhibidores de la Bomba de Protones/toxicidad , Receptor ErbB-2/metabolismo , Fosfatasa Ácida/metabolismo , Animales , Apoptosis/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos NOD , Ratones SCID , Neoplasias Hormono-Dependientes/patología , Células PC-3 , Fosforilación , Neoplasias de la Próstata/patología , Transducción de SeñalRESUMEN
Glioblastoma (GBM) is the brain tumor with the worst prognosis composed of a cell subpopulation called Glioblastoma Stem-like Cells (GSCs) responsible for tumor recurrence mediated by cell invasion. GSCs persist in a hypoxic microenvironment which promotes extracellular adenosine production and activation of the A3 Adenosine Receptor (A3AR), therefore, the aim of this study was to determine the role of extracellular adenosine and A3AR on GSCs invasion under hypoxia. GSCs were obtained from a U87MG cell line and primary cultures of GBM patients, and then incubated under normoxia or hypoxia. Gene expression was evaluated by RNAseq, RT-qPCR, and western blot. Cell migration was measured by spreading and transwell boyden chamber assays; cell invasion was evaluated by Matrigel-coated transwell, ex vivo brain slice, and in vivo xenograft assays. The contribution of A3AR on cell migration/invasion was evaluated using the A3AR antagonist, MRS1220. Extracellular adenosine production was higher under hypoxia than normoxia, mainly by the catalytic action of the prostatic acid phosphatase (PAP), promoting cell migration/invasion in a HIF-2-dependent process. A3AR blockade decreased cell migration/invasion and the expression of Epithelial-Mesenchymal Transition markers. In conclusion, high levels of extracellular adenosine production enhance cell migration/invasion of GSCs, through HIF-2/PAP-dependent activation of A3AR under hypoxia.
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Adenosina/metabolismo , Neoplasias Encefálicas/metabolismo , Movimiento Celular , Glioblastoma/metabolismo , Células Madre Neoplásicas/metabolismo , Receptor de Adenosina A3/metabolismo , Fosfatasa Ácida/genética , Fosfatasa Ácida/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioblastoma/genética , Glioblastoma/patología , Humanos , Ratones Endogámicos NOD , Ratones SCID , Invasividad Neoplásica , Células Madre Neoplásicas/patología , Receptor de Adenosina A3/genética , Transducción de Señal , Células Tumorales Cultivadas , Hipoxia Tumoral , Microambiente TumoralRESUMEN
Specialized microdomains which have cholesterol-rich membrane regions contain transient receptor potential vanilloid subtype 1 (TRPV1) are involved in pain development. Our previous studies have demonstrated that the depletion of prostatic acid phosphatase (PAP) - a membrane-bound ectonucleotidase -- and disordered adenosine signaling reduce the antinociceptive effect. The role of membrane integrity in the PAP-mediated antinociceptive effect in small-fiber neuropathy remains unclear, especially with respect to whether TRPV1 and PAP are colocalized in the same microdomain which is responsible for PAP-mediated antinociception. Immunohistochemistry was conducted on the dorsal root ganglion to identify the membrane compositions, and pharmacological interventions were conducted using methyl-ß-cyclodextrin (MßC) - a membrane integrity disruptor that works by depleting cholesterol - in pure small-fiber neuropathy with resiniferatoxin (RTX). Immunohistochemical evidence indicated that TRPV1 and PAP were highly colocalized with flotillin 1 (66.7%±9.7%) and flotillin 2 (73.7%±6.0%), which reside in part in the microdomain. MßC mildly depleted PAP, which maintained the ability to hydrolyze phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and delayed the development of mechanical allodynia. MßC treatment had no role in thermal transduction and neuronal injury following RTX neuropathy. In summary, this study demonstrated the following: (1) membrane cholesterol depletion preserves PAP-mediated antinociception through PI(4,5)P2 hydrolysis and (2) pain hypersensitivity that develops after TRPV1(+) neuron depletion-mediated neurodegeneration following RTX neuropathy is attributable to the downregulation of PAP analgesic signaling.
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Background. Sipuleucel T, an autologous cell-based vaccine targeting prostatic acid phosphatase (PAP), has demonstrated efficacy for the treatment of advanced prostate cancer. DNA vaccines encoding PAP and live attenuated Listeria vaccines have entered clinical trials for patients with prostate cancer, and have advantages in terms of eliciting predominantly Th1-biased immunity. In this study, we investigated whether the immunogenicity and anti-tumor efficacy of a DNA and Listeria vaccine, each encoding PAP, could be enhanced by using them in a heterologous prime/boost approach. Methods. Transgenic mice expressing HLA-A2.01 and HLA-DRB1*0101 were immunized alone or with a heterologous prime/boost strategy. Splenocytes were evaluated for MHC class I and II-restricted, PAP-specific immune responses by IFNγ ELISPOTs. Anti-tumor activity to a syngeneic, PAP-expressing tumor line was evaluated. Results. PAP-specific cellular immunity and anti-tumor activity were elicited in mice after immunization with DNA- or listeria-based vaccines. Greater CD4+ and CD8+ responses, and anti-tumor responses, were elicited when mice were immunized first with DNA and boosted with Listeria, but not when administered in the opposite order. This was found to be dependent on CD4+ T cells elicited with DNA priming, and was not due to inflammatory signals by Listeria itself or due to B cells serving as antigen-presenting cells for DNA during priming. Conclusions. Heterologous prime/boost vaccination using DNA priming with Listeria boosting may provide better anti-tumor immunity, similar to many reports evaluating DNA priming with vaccines targeting foreign microbial antigens. These findings have implications for the design of future clinical trials.
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T-cell checkpoint inhibitors have demonstrated dramatic clinical activity against multiple cancer types, however little activity in patients with prostate cancer. Conversely, an anti-tumor vaccine was approved for the treatment of prostate cancer, having demonstrated an improvement in overall survival, despite few objective disease responses. In murine studies, we found that PD-1 expression on CD8+ T cells increased following anti-tumor vaccination, and that PD-1/PD-L1 blockade at the time of immunization elicited greater anti-tumor responses. Based on these data we initiated a pilot trial evaluating the immunological and clinical efficacy of a DNA encoding prostatic acid phosphatase (PAP) when delivered in combination with pembrolizumab. 26 patients were treated for 12 weeks with vaccine and received pembrolizumab either during this time or during the subsequent 12 weeks. Adverse events included grade 2 and 3 fatigue, diarrhea, thyroid dysfunction, and hepatitis. Median time to radiographic progression was not different between study arms. 8/13 (62%) of patients treated concurrently, and 1/12 (8%, p=0.01) of patients treated sequentially, experienced PSA declines from baseline. Of these, two were over 50% and one was a complete PSA response. No confirmed CR or PR were observed, however 4/5 patients treated concurrently had measurable decreases in tumor volume at 12 weeks. PSA declines were associated with the development of PAP-specific Th1-biased T cell immunity and CD8+ T cell infiltration in metastatic tumor biopsy specimens. These data are the first report of a clinical trial demonstrating that the efficacy of an anti-tumor vaccine can be augmented by concurrent PD-1 blockade.
RESUMEN
BACKGROUND: Prostatic acid phosphatase (PAP) is a prostate tumor antigen, and the target of the only FDA-approved anti-tumor vaccine, sipuleucel-T. We have previously reported in two clinical trials that a DNA vaccine encoding PAP (pTVG-HP) could elicit PAP-specific, Th1-biased T cells in patients with PSA-recurrent prostate cancer. In the current pilot trial we sought to evaluate whether this vaccine could augment PAP-specific immunity when used as a booster to immunization with sipuleucel-T in patients with metastatic, castration-resistant prostate cancer (mCRPC). METHODS: Eigthteen patients with mCRPC were randomized to receive sipuleucel-T alone or followed by intradermal immunization with pTVG-HP DNA vaccine. Patients were followed for time to progression, and immune monitoring was conducted at defined intervals. RESULTS: Overall, patients were followed for a median of 24 months. 11/18 patients completed treatments as per protocol. No treatment-associated events > grade 2 were observed. Th1-biased PAP-specific T-cell responses were detected in 11/18 individuals, and were not statistically different between study arms. Higher titer antibody responses to PAP were detectable in patients who received pTVG-HP booster immunizations. Median time to progression was less than 6 months and not statistically different between study arms. The median overall survival for all patients was 28 months. CONCLUSIONS: These findings suggest that prime-boost vaccination can augment and diversify the type of immunity elicited with anti-tumor vaccination in terms of T-cell and humoral immunity. Future studies will explore DNA as priming immunization rather than a booster immunization. TRIAL REGISTRATION: NCT01706458 .