RESUMEN
Reduced infiltration of anti-tumor lymphocytes remains a major cause of tumor immune evasion and is correlated with poor cancer survival. Here, we found that upregulation of regulator of G protein signaling (RGS)1 in helper TH1 cells and cytotoxic T lymphocytes (CTLs) reduced their trafficking to and survival in tumors and was associated with shorter survival of patients with breast and lung cancer. RGS1 was upregulated by type II interferon (IFN)-signal transducer and activator of transcription (STAT)1 signaling and impaired trafficking of circulating T cells to tumors by inhibiting calcium influx and suppressing activation of the kinases ERK and AKT. RGS1 knockdown in adoptively transferred tumor-specific CTLs significantly increased their infiltration and survival in breast and lung tumor grafts and effectively inhibited tumor growth in vivo, which was further improved when combined with programmed death ligand (PD-L)1 checkpoint inhibition. Our findings reveal RGS1 is important for tumor immune evasion and suggest that targeting RGS1 may provide a new strategy for tumor immunotherapy.
Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Quimiotaxis de Leucocito , Linfocitos Infiltrantes de Tumor/metabolismo , Proteínas RGS/metabolismo , Subgrupos de Linfocitos T/metabolismo , Animales , Apoptosis , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Carcinoma Ductal de Mama/inmunología , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/terapia , Línea Celular Tumoral , Quimiocinas/metabolismo , Técnicas de Cocultivo , Citotoxicidad Inmunológica , Femenino , Humanos , Inmunoterapia Adoptiva , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/trasplante , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Microscopía Fluorescente , Microscopía por Video , Proteínas RGS/genética , Transducción de Señal , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/trasplante , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Células TH1/inmunología , Células TH1/metabolismo , Factores de Tiempo , Imagen de Lapso de Tiempo , Células Tumorales Cultivadas , Escape del TumorRESUMEN
Carcinoma-associated fibroblasts (CAFs) are abundant and heterogeneous stromal cells in tumor microenvironment that are critically involved in cancer progression. Here, we demonstrate that two cell-surface molecules, CD10 and GPR77, specifically define a CAF subset correlated with chemoresistance and poor survival in multiple cohorts of breast and lung cancer patients. CD10+GPR77+ CAFs promote tumor formation and chemoresistance by providing a survival niche for cancer stem cells (CSCs). Mechanistically, CD10+GPR77+ CAFs are driven by persistent NF-κB activation via p65 phosphorylation and acetylation, which is maintained by complement signaling via GPR77, a C5a receptor. Furthermore, CD10+GPR77+ CAFs promote successful engraftment of patient-derived xenografts (PDXs), and targeting these CAFs with a neutralizing anti-GPR77 antibody abolishes tumor formation and restores tumor chemosensitivity. Our study reveals a functional CAF subset that can be defined and isolated by specific cell-surface markers and suggests that targeting the CD10+GPR77+ CAF subset could be an effective therapeutic strategy against CSC-driven solid tumors.
Asunto(s)
Transformación Celular Neoplásica/inmunología , Resistencia a Antineoplásicos/inmunología , Fibroblastos/inmunología , Neoplasias/inmunología , Células Madre Neoplásicas/inmunología , Neprilisina/inmunología , Receptores de Quimiocina/inmunología , Microambiente Tumoral/inmunología , Células A549 , Transformación Celular Neoplásica/patología , Fibroblastos/patología , Humanos , Células MCF-7 , Proteínas de Neoplasias/inmunología , Neoplasias/patología , Células Madre Neoplásicas/patología , Receptor de Anafilatoxina C5aRESUMEN
Activation-induced cell death (AICD) of T lymphocytes can be exploited by cancers to escape immunological destruction. We demonstrated that tumor-specific cytotoxic T lymphocytes (CTLs) and type 1 helper T (TH1) cells, rather than type 2 helper T cells and regulatory T cells, were sensitive to AICD in breast and lung cancer microenvironments. NKILA, an NF-κB-interacting long noncoding RNA (lncRNA), regulates T cell sensitivity to AICD by inhibiting NF-κB activity. Mechanistically, calcium influx in stimulated T cells via T cell-receptor signaling activates calmodulin, thereby removing deacetylase from the NKILA promoter and enhancing STAT1-mediated transcription. Administering CTLs with NKILA knockdown effectively inhibited growth of breast cancer patient-derived xenografts in mice by increasing CTL infiltration. Clinically, NKILA overexpression in tumor-specific CTLs and TH1 cells correlated with their apoptosis and shorter patient survival. Our findings underscore the importance of lncRNAs in determining tumor-mediated T cell AICD and suggest that engineering lncRNAs in adoptively transferred T cells might provide a novel antitumor immunotherapy.
Asunto(s)
Carcinoma/inmunología , ARN Largo no Codificante/inmunología , Linfocitos T Citotóxicos/inmunología , Células TH1/inmunología , Escape del Tumor/genética , Animales , Apoptosis/inmunología , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Carcinoma/genética , Carcinoma/patología , Femenino , Xenoinjertos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Masculino , Ratones Endogámicos NOD , Ratones SCID , ARN Largo no Codificante/genéticaRESUMEN
Neutrophil extracellular traps (NETs), which consist of chromatin DNA filaments coated with granule proteins, are released by neutrophils to trap microorganisms1-3. Recent studies have suggested that the DNA component of NETs (NET-DNA) is associated with cancer metastasis in mouse models4-6. However, the functional role and clinical importance of NET-DNA in metastasis in patients with cancer remain unclear. Here we show that NETs are abundant in the liver metastases of patients with breast and colon cancers, and that serum NETs can predict the occurrence of liver metastases in patients with early-stage breast cancer. NET-DNA acts as a chemotactic factor to attract cancer cells, rather than merely acting as a 'trap' for them; in several mouse models, NETs in the liver or lungs were found to attract cancer cells to form distant metastases. We identify the transmembrane protein CCDC25 as a NET-DNA receptor on cancer cells that senses extracellular DNA and subsequently activates the ILK-ß-parvin pathway to enhance cell motility. NET-mediated metastasis is abrogated in CCDC25-knockout cells. Clinically, we show that the expression of CCDC25 on primary cancer cells is closely associated with a poor prognosis for patients. Overall, we describe a transmembrane DNA receptor that mediates NET-dependent metastasis, and suggest that targeting CCDC25 could be an appealing therapeutic strategy for the prevention of cancer metastasis.
Asunto(s)
Neoplasias de la Mama/patología , ADN/metabolismo , Trampas Extracelulares/genética , Proteínas de la Membrana/metabolismo , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/patología , Neutrófilos/metabolismo , Actinina/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Femenino , Humanos , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Proteínas de la Membrana/genética , Ratones , Pronóstico , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de SeñalRESUMEN
TGF-ß plays a central role in mediating epithelial-mesenchymal transition (EMT) by activating the Smad pathway. In addition, accumulating evidence suggests that TGF-ß-induced EMT is NF-κB-dependent in various cancer types. However, it is largely unclear if NF-κB mediates TGF-ß-induced EMT in breast cancer, and if this mediation occurs, the regulatory mechanisms are unknown. In our study, we found that TGF-ß activates the NF-κB pathway. Inhibition of NF-κB signaling markedly abrogates TGF-ß-induced EMT. By studying the regulatory mechanism of TGF-ß-induced NF-κB signaling, we found that lncRNA NKILA was upregulated by TGF-ß and was essential for the negative feedback regulation of the NF-κB pathway. Accordingly, overexpression of NKILA significantly reduced TGF-ß-induced tumor metastasis in vivo. Consistent with the results from mice, the expression of NKILA was negatively correlated with EMT phenotypes in clinical breast cancer samples. Collectively, our study indicated that the NKILA-mediated negative feedback affects TGF-ß-induced NF-κB activation and that NKILA may be a therapeutic molecule in breast cancer metastasis via inhibition of EMT.
Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Cadherinas/metabolismo , Transición Epitelial-Mesenquimal , FN-kappa B/metabolismo , ARN Largo no Codificante/genética , Factor de Crecimiento Transformador beta/farmacología , Animales , Apoptosis , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Cadherinas/genética , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , FN-kappa B/genética , Transducción de Señal , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Neutrophils are recognized active participants in inflammatory responses and are intricately linked to cancer progression. In response to inflammatory stimuli, neutrophils become activated, releasing neutrophils extracellular traps (NETs) for the capture and eradication of pathogens, a phenomenon termed NETosis. With a deeper understanding of NETs, there is growing evidence supporting their role in cancer progression and their involvement in conferring resistance to various cancer therapies, especially concerning tumor reactions to chemotherapy, radiation therapy (RT), and immunotherapy. This review summarizes the roles of NETs in the tumor microenvironment (TME) and their mechanisms of neutrophil involvement in the host defense. Additionally, it elucidates the mechanisms through which NETs promote tumor progression and their role in cancer treatment resistance, highlighting their potential as promising therapeutic targets in cancer treatment and their clinical applicability.
RESUMEN
Basal-like breast cancer (BLBC) is the most aggressive molecular subtype of breast cancer with worse prognosis and fewer treatment options. The underlying mechanisms upon BLBC transcriptional dysregulation and its upstream transcription factors (TFs) remain unclear. Here, among the hyperactive candidate TFs of BLBC identified by bioinformatic analysis, POU4F1 is uniquely upregulated in BLBC and is associated with poor prognosis. POU4F1 is necessary for the tumor growth and malignant phenotypes of BLBC through regulating G1/S transition by direct binding at the promoter of CDK2 and CCND1. More importantly, POU4F1 maintains BLBC identity by repressing ERα expression through CDK2-mediated EZH2 phosphorylation and subsequent H3K27me3 modification in ESR1 promoter. Knocking out POU4F1 in BLBC cells reactivates functional ERα expression, rendering BLBC sensitive to tamoxifen treatment. In-depth epigenetic analysis reveals that the subtype-specific re-configuration and activation of the bivalent chromatin in the POU4F1 promoter contributes to its unique expression in BLBC, which is maintained by DNA demethylase TET1. Together, these results reveal a subtype-specific epigenetically activated TF with critical role in promoting and maintaining BLBC, suggesting that POU4F1 is a potential therapeutic target for BLBC.
Asunto(s)
Neoplasias de la Mama , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Humanos , Femenino , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/genética , Ratones , Animales , Factor de Transcripción Brn-3A/genética , Factor de Transcripción Brn-3A/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Modelos Animales de Enfermedad , Regiones Promotoras Genéticas/genéticaRESUMEN
The therapeutic efficacy of chemotherapy is in part a result of its ability to enhance adaptive antitumor immune responses. However, tumor cells exploit various evasion mechanisms to escape the immune attack and blunt chemosensitivity. Herein, we report that through single-cell profiling of the tumor immune microenvironment, we identified a subset of CD161-overexpressing CD8+ T cells enriched in chemoresistant tumors. CD161 engagement repressed the calcium influx and cytolytic capacity of CD8+ T cells through acid sphingomyelinase activation and ceramide generation. Targeting CD161 in adoptively transferred cytotoxic T lymphocytes enhanced antitumor immunity and reversed chemoresistance in patient-derived xenografts in vivo. Clinically, CD161 expression on CD8+ T cells was associated with chemoresistance and shortened patient survival. Our findings provide insights into novel immunosuppressive mechanisms in chemoresistance and highlight targeting CD161 as a potential therapeutic strategy.
Asunto(s)
Resistencia a Antineoplásicos , Microambiente Tumoral , Humanos , Linfocitos T CD8-positivos , Inmunosupresores , AnimalesRESUMEN
Although chemotherapy can stimulate antitumor immunity by inducing interferon (IFN) response, the functional role of tumor-associated macrophages in this scenario remains unclear. Here, we found that IFN-activated proinflammatory macrophages after neoadjuvant chemotherapy enhanced antitumor immunity but promoted cancer chemoresistance. Mechanistically, IFN induced expression of cytoplasmic long noncoding RNA IFN-responsive nuclear factor-κB activator (IRENA) in macrophages, which triggered nuclear factor-κB signaling via dimerizing protein kinase R and subsequently increased production of protumor inflammatory cytokines. By constructing macrophage-conditional IRENA-knockout mice, we found that targeting IRENA in IFN-activated macrophages abrogated their protumor effects, while retaining their capacity to enhance antitumor immunity. Clinically, IRENA expression in post-chemotherapy macrophages was associated with poor patient survival. These findings indicate that lncRNA can determine the dichotomy of inflammatory cells on cancer progression and antitumor immunity and suggest that targeting IRENA is an effective therapeutic strategy to reversing tumor-promoting inflammation.
Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Animales , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Macrófagos , Ratones , FN-kappa B/genética , Fenotipo , ARN Largo no Codificante/genéticaRESUMEN
PURPOSE: The different prognostic values of tumor-infiltrating neutrophils (TIN) in different tissue compartments are unknown. In this study, we investigated their different prognostic roles and the underlying mechanism.Experimental Design: We evaluated CD66b+ neutrophils in primary tumors from 341 patients with breast cancer from Sun Yat-sen Memorial Hospital by IHC. The association between stromal and parenchymal neutrophil counts and clinical outcomes was assessed in a training set (170 samples), validated in an internal validation set (171 samples), and further confirmed in an external validation set (105 samples). In addition, we isolated TINs from clinical samples and screened the cytokine profile by antibody microarray. The interaction between neutrophils and tumor cells was investigated in transwell and 3D Matrigel coculture systems. The therapeutic potential of indicated cytokines was evaluated in tumor-bearing immunocompetent mice. RESULTS: We observed that the neutrophils in tumor parenchyma, rather than those in stroma, were an independent poor prognostic factor in the training [HR = 5.00, 95% confidence interval (CI): 2.88-8.68, P < 0.001], internal validation (HR = 3.56, 95% CI: 2.07-6.14, P < 0.001), and external validation set (HR = 5.07, 95% CI: 2.27-11.33, P < 0.001). The mechanistic study revealed that neutrophils induced breast cancer epithelial-mesenchymal transition (EMT) via tissue inhibitor of matrix metalloprotease (TIMP-1). Reciprocally, breast cancer cells undergoing EMT enhanced neutrophils' TIMP-1 secretion by CD90 in a cell-contact manner. In vivo, TIMP-1 neutralization or CD90 blockade significantly reduced metastasis. More importantly, TIMP-1 and CD90 were positively correlated in breast cancer (r 2 = 0.6079; P < 0.001) and associated with poor prognosis of patients. CONCLUSIONS: Our findings unravel a location-dictated interaction between tumor cells and neutrophils and provide a rationale for new antimetastasis treatments.
Asunto(s)
Neoplasias de la Mama/patología , Neutrófilos/inmunología , Comunicación Paracrina/inmunología , Antígenos Thy-1/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Animales , Mama/inmunología , Mama/patología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Supervivencia sin Enfermedad , Transición Epitelial-Mesenquimal/inmunología , Femenino , Humanos , Ratones , Neutrófilos/metabolismo , Cultivo Primario de Células , Pronóstico , Células Tumorales CultivadasRESUMEN
PURPOSE: More than 30% of patients with diffuse large B-cell lymphoma (DLBCL) experience treatment failure after first-line therapy. Neutrophil extracellular traps (NETs), a pathogen-trapping structure in tumor microenvironment, can promote the transition of autoimmunity to lymphomagenesis. Here, we investigate whether NETs play a novel role in DLBCL progression and its underlying mechanism.Experimental Design: NETs in DLBCL tumor samples and plasma were detected by immunofluorescence and ELISA, respectively. The correlation between NETs and clinical features were analyzed. The effects of NETs on cellular proliferation and migration and mechanisms were explored, and the mechanism of NET formation was also studied by a series of in vitro and in vivo assays. RESULTS: Higher levels of NETs in plasma and tumor tissues were associated with dismal outcome in patients with DLBCL. Furthermore, we identified NETs increased cell proliferation and migration in vitro and tumor growth and lymph node dissemination in vivo. Mechanistically, DLBCL-derived IL8 interacted with its receptor (CXCR2) on neutrophils, resulting in the formation of NETs via Src, p38, and ERK signaling. Newly formed NETs directly upregulated the Toll-like receptor 9 (TLR9) pathways in DLBCL and subsequently activated NFκB, STAT3, and p38 pathways to promote tumor progression. More importantly, disruption of NETs, blocking IL8-CXCR2 axis or inhibiting TLR9 could retard tumor progression in preclinical models. CONCLUSIONS: Our data reveal a tumor-NETs aggressive interaction in DLBCL and indicate that NETs is a useful prognostic biomarker and targeting this novel cross-talk represents a new therapeutic opportunity in this challenging disease.
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Trampas Extracelulares/inmunología , Interleucina-8/metabolismo , Linfoma de Células B Grandes Difuso/patología , Neutrófilos/inmunología , Receptor Toll-Like 9/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Autoinmunidad , Línea Celular Tumoral/trasplante , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Interleucina-8/inmunología , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Neutrófilos/metabolismo , Supervivencia sin Progresión , Receptores de Interleucina-8B/inmunología , Receptores de Interleucina-8B/metabolismo , Transducción de Señal/inmunología , Receptor Toll-Like 9/inmunología , Microambiente Tumoral/inmunología , Adulto JovenRESUMEN
Metabolic reprogramming is a hallmark of cancer. Here, we demonstrate that tumour-associated macrophages (TAMs) enhance the aerobic glycolysis and apoptotic resistance of breast cancer cells via the extracellular vesicle (EV) transmission of a myeloid-specific lncRNA, HIF-1α-stabilizing long noncoding RNA (HISLA). Mechanistically, HISLA blocks the interaction of PHD2 and HIF-1α to inhibit the hydroxylation and degradation of HIF-1α. Reciprocally, lactate released from glycolytic tumour cells upregulates HISLA in macrophages, constituting a feed-forward loop between TAMs and tumour cells. Blocking EV-transmitted HISLA inhibits the glycolysis and chemoresistance of breast cancer in vivo. Clinically, HISLA expression in TAMs is associated with glycolysis, poor chemotherapeutic response and shorter survival of patients with breast cancer. Our study highlights the potential of lncRNAs as signal transducers that are transmitted between immune and tumour cells via EVs to promote cancer aerobic glycolysis.
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Neoplasias de la Mama/metabolismo , Vesículas Extracelulares/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Macrófagos/metabolismo , ARN Largo no Codificante/metabolismo , Aerobiosis , Apoptosis , Neoplasias de la Mama/genética , Línea Celular Tumoral , Células Cultivadas , Vesículas Extracelulares/genética , Femenino , Glucólisis , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Ácido Láctico/metabolismo , Microambiente TumoralRESUMEN
Trastuzumab is a standard treatment for HER2-positive (HER2+) breast cancer, but some patients are refractory to the therapy. MicroRNAs (miRNAs) have been used to predict therapeutic effects for various cancers, but whether miRNAs can serve as biomarkers for HER2+ metastatic breast cancer (MBC) patients remains unclear. Using miRNA microarray, we identify 13 differentially expressed miRNAs in the serum of HER2+ MBC patients with distinct response to trastuzumab, and four miRNAs are selected to construct a signature to predict survival using LASSO model. Further, our data show that miR-940 is mainly released from the tumor cells and miR-451a, miR-16-5p and miR-17-3p are mainly from the immune cells. All these four miRNAs directly target signaling molecules that play crucial roles in regulating trastuzumab resistance. In summary, we develop a serum-based miRNA signature that potentially predicts the therapeutic benefit of trastuzumab for HER2+ MBC patients and warrants future validation in prospective clinical trials.
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Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , MicroARNs/sangre , Receptor ErbB-2/metabolismo , Trastuzumab/administración & dosificación , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Estudios de Cohortes , Monitoreo de Drogas , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Metástasis de la Neoplasia , Estudios Prospectivos , Receptor ErbB-2/genéticaAsunto(s)
Eosinofilia/patología , Enfermedades Ureterales/patología , Adulto , Eosinofilia/diagnóstico por imagen , Eosinofilia/cirugía , Femenino , Humanos , Inflamación/patología , Tomografía Computarizada por Rayos X , Enfermedades Ureterales/diagnóstico por imagen , Enfermedades Ureterales/cirugíaRESUMEN
Jatropha hulls were successfully for the first time used as raw materials for the production of 2,3-butanediol via dilute sulfuric acid hydrolysis and fermentation with Klebsiella oxytoca. Two-step hydrolysis was used to effectively hydrolyze the hulls at 150°C after pretreatment. In the first-step, hemicellulose was hydrolyzed under mild conditions (0.5h, 1.5% acid) to avoid secondary decomposition. The remained cellulose was further hydrolyzed in the second-step under severer conditions (1h, 4% acid). After hydrolysis, total hydrolysis yield was 64%, which was much higher than that (37%) from the first-step. Maximum yields of 2,3-butanediol and acetoin in flask experiments were 35.6% and 41.4% from the hydrolysates of the first- and second-step hydrolysis, equivalent to 71.2% and 82.8% of the theoretical values, respectively. Similar yields were obtained in a controlled bioreactor but with higher productivities. Jatropha hulls are attractive raw materials for the production of 2,3-butanediol with high yield.
Asunto(s)
Butileno Glicoles/metabolismo , Jatropha/metabolismo , Klebsiella oxytoca/metabolismo , Celulosa/metabolismo , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Hidrólisis , Espectrofotometría UltravioletaRESUMEN
BACKGROUND AND PURPOSE: Retrograde ureteroscopic marsupialization is a pure natural orifice translumenal endoscopic surgery (NOTES). We retrospectively examined the feasibility and safety of this technique to manage symptomatic simple renal cysts. PATIENTS AND METHODS: Sixteen patients with simple renal cysts were selected and treated by incising the cyst wall to drain into the collecting system through retrograde ureteroscopy. A retrospective observational study was performed to evaluate the patient's symptomatic and radiologic results after ureteroscopic marsupialization. Symptomatic success based on pain relief was evaluated using a visual analog pain scale preoperatively and postoperatively. Radiologic success was defined as no recurrence of the cyst or a reduction in cyst size by at least half. RESULTS: There were no intraoperative or postoperative complications observed. The mean operative time was 35 minutes (range 20-50 min). The mean hospital stay was 3.4 days (range 2-5 d). Of the 16 patients, one patient was lost at follow-up. The symptoms based on pain had resolved in 13 (83%) cases but remained in 2 cases at a mean follow-up of 24.2 months (range 6-36 mos). The average visual analog pain scale decreased from 6.7 (range 4-9) to 1.1 (range 0-5) at the sixth month. The mean size of all cysts decreased from 6.8 cm (range 4-10 cm) to 1.3 cm (range 0-5 cm). Radiographic success was achieved in 93% (14/15) of patients. Cytology and cyst wall pathology reports revealed no evidence of malignancy. CONCLUSIONS: Retrograde ureteroscopic marsupialization is a complete transurethral NOTES marsupialization. With appropriate patient selection, the minimally invasive retrograde ureteroscopic marsupialization is feasible, safe, and effective. It can be preferred to more invasive laparoscopic or open surgical approaches.