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1.
MedComm (2020) ; 5(7): e618, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38974711

RESUMO

T-cell receptor (TCR) engineered T-cell therapy, unlike chimeric antigen receptor T-cell therapy, relies on the inherent ability of TCRs to detect a wider variety of antigenic epitopes, such as protein fragments found internally or externally on cells. Hence, TCR-T-cell therapy offers broader possibilities for treating solid tumors. However, because of the complicated process of identifying specific antigenic peptides, their clinical application still encounters significant challenges. Thus, we aimed to establish a novel "universal" TCR-T "artificial antigen expression" technique that involves the delivery of the antigen to tumor cells using DSPE-PEG-NY-ESO-1157-165 liposomes (NY-ESO-1 Lips) to express TCR-T-cell-specific recognition targets. In vitro as well as in vivo studies revealed that they could accumulate efficiently in the tumor area and deliver target antigens to activate the tumor-specific cytotoxic T-cell immune response. NY-ESO-1 TCR-T therapy, when used in combination, dramatically curbed tumor progression and extended the longevity of mice. Additionally, PD-1 blockage enhanced the therapeutic effect of the aforementioned therapy. In conclusion, NY-ESO-1 Lips "cursed" tumor cells by enabling antigenic target expression on their surface. This innovative technique presents a groundbreaking approach for the widespread utilization of TCR-T in solid tumor treatment.

2.
World J Gastrointest Oncol ; 16(5): 1808-1820, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38764811

RESUMO

BACKGROUND: Vessels encapsulating tumor clusters (VETC) represent a recently discovered vascular pattern associated with novel metastasis mechanisms in hepatocellular carcinoma (HCC). However, it seems that no one have focused on predicting VETC status in small HCC (sHCC). This study aimed to develop a new nomogram for predicting VETC positivity using preoperative clinical data and image features in sHCC (≤ 3 cm) patients. AIM: To construct a nomogram that combines preoperative clinical parameters and image features to predict patterns of VETC and evaluate the prognosis of sHCC patients. METHODS: A total of 309 patients with sHCC, who underwent segmental resection and had their VETC status confirmed, were included in the study. These patients were recruited from three different hospitals: Hospital 1 contributed 177 patients for the training set, Hospital 2 provided 78 patients for the test set, and Hospital 3 provided 54 patients for the validation set. Independent predictors of VETC were identified through univariate and multivariate logistic analyses. These independent predictors were then used to construct a VETC prediction model for sHCC. The model's performance was evaluated using the area under the curve (AUC), calibration curve, and clinical decision curve. Additionally, Kaplan-Meier survival analysis was performed to confirm whether the predicted VETC status by the model is associated with early recurrence, just as it is with the actual VETC status and early recurrence. RESULTS: Alpha-fetoprotein_lg10, carbohydrate antigen 199, irregular shape, non-smooth margin, and arterial peritumoral enhancement were identified as independent predictors of VETC. The model incorporating these predictors demonstrated strong predictive performance. The AUC was 0.811 for the training set, 0.800 for the test set, and 0.791 for the validation set. The calibration curve indicated that the predicted probability was consistent with the actual VETC status in all three sets. Furthermore, the decision curve analysis demonstrated the clinical benefits of our model for patients with sHCC. Finally, early recurrence was more likely to occur in the VETC-positive group compared to the VETC-negative group, regardless of whether considering the actual or predicted VETC status. CONCLUSION: Our novel prediction model demonstrates strong performance in predicting VETC positivity in sHCC (≤ 3 cm) patients, and it holds potential for predicting early recurrence. This model equips clinicians with valuable information to make informed clinical treatment decisions.

3.
Abdom Radiol (NY) ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713432

RESUMO

BACKGROUND: Vessels Encapsulating Tumor Clusters (VETC) are now recognized as independent indicators of recurrence and overall survival in hepatocellular carcinoma (HCC) patients. However, there has been limited investigation into predicting the VETC pattern using hepatobiliary phase (HBP) features from preoperative gadobenate-enhanced MRI. METHODS: This study involved 252 HCC patients with confirmed VETC status from three different hospitals (Hospital 1: training set with 142 patients; Hospital 2: test set with 64 patients; Hospital 3: validation set with 46 patients). Independent predictive factors for VETC status were determined through univariate and multivariate logistic analyses. Subsequently, these factors were used to construct two distinct VETC prediction models. Model 1 included all independent predictive factors, while Model 2 excluded HBP features. The performance of both models was assessed using the Area Under the Curve (AUC), Decision Curve Analysis, and Calibration Curve. Prediction accuracy between the two models was compared using Net Reclassification Improvement (NRI) and Integrated Discriminant Improvement (IDI). RESULTS: CA199, IBIL, shape, peritumoral hyperintensity on HBP, and arterial peritumoral enhancement were independent predictors of VETC. Model 1 showed robust predictive performance, with AUCs of 0.836 (training), 0.811 (test), and 0.802 (validation). Model 2 exhibited moderate performance, with AUCs of 0.813, 0.773, and 0.783 in the respective sets. Calibration and decision curves for both models indicated consistent predictions between predicted and actual VETC, benefiting HCC patients. NRI showed Model 1 increased by 0.326, 0.389, and 0.478 in the training, test, and validation sets compared to Model 2. IDI indicated Model 1 increased by 0.036, 0.028, and 0.025 in the training, test, and validation sets compared to Model 2. CONCLUSION: HBP features from preoperative gadobenate-enhanced MRI can enhance the predictive performance of VETC in HCC.

4.
Abdom Radiol (NY) ; 49(3): 710-721, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38112787

RESUMO

PURPOSE: Microvascular invasion (MVI) is a significant prognostic factor in combined hepatocellular cholangiocarcinoma (cHCC-CCA). However, its diagnosis relies on postoperative histopathologic analysis. This study aims to identify preoperative inflammatory biomarkers and MR-imaging features that can predict MVI in cHCC-CCA. METHODS: This retrospective study enrolled 119 patients with histopathologically confirmed cHCC-CCA between January 2016 and December 2021. Two radiologists, unaware of the clinical data, independently reviewed all MR image features. Univariable and multivariable analyses were performed to determine the independent predictors for MVI among inflammatory biomarkers and MRI characteristics. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the diagnostic performance. RESULTS: Multivariable logistic regression analysis identified four variables significantly associated with MVI (p < 0.05), including two inflammatory biomarkers [albumin-to-alkaline phosphatase ratio (AAPR) and aspartate aminotransferase-to-neutrophil ratio index (ANRI)] and two MRI features (non-smooth tumor margin and arterial phase peritumoral enhancement). A combined model for predicting MVI was constructed based on these four variables, with an AUC of 0.802 (95% CI 0.719-0.870). The diagnostic efficiency of the combined model was higher than that of the imaging model. CONCLUSION: Inflammatory biomarkers and MRI features could be potential predictors for MVI in cHCC-CCA. The combined model, derived from inflammatory biomarkers and MRI features, showed good performance in preoperatively predicting MVI in cHCC-CCA patients.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Invasividade Neoplásica , Imageamento por Ressonância Magnética/métodos , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Biomarcadores , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia
5.
Front Oncol ; 13: 1186290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37675222

RESUMO

Objective: To evaluate the usefulness of the apparent diffusion coefficient (ADC) in differentiating between benign and malignant LR-3 lesions classified by Liver Imaging Reporting and Data System 2018 (LI-RADS v2018). Methods: Retrospectively analyzed 88 patients with liver nodules confirmed by pathology and classified as LR-3 by LI-RADS. All patients underwent preoperative contrast-enhanced MR examination, and the following patient-related imaging features were collected: tumor size,nonrim APHE, nonperipheral "washout", enhancing "capsule", mild-moderate T2 hyperintensity, fat in mass, restricted diffusion, and nodule-in-nodule architecture. We performed ROC analysis and calculated the sensitivity and specificity. Results: A total of 122 lesions were found in 88 patients, with 68 benign and 54 malignant lesions. The mean ADC value for malignant and benign lesions were 1.01 ± 0.15 × 103 mm2/s and 1.41 ± 0.31 × 103 mm2/s, respectively. The ADC value of malignant lesions was significantly lower than that of benign lesions, p < 0.0001. Compared with other imaging features, ADC values had the highest AUC (AUC = 0.909), with a sensitivity of 92.6% and a specificity of 74.1% for the differentiation of benign and malignant lesions. Conclusions: ADC values are useful for differentiating between benign and malignant liver nodules in LR-3 classification, it improves the sensitivity of LI-RADS in the diagnosis of HCC while maintaining high specificity, and we recommend including ADC values in the standard interpretation of LI-RADSv2018.

6.
Phenomics ; 3(6): 549-564, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38223688

RESUMO

It is widely recognized that tumor immune microenvironment (TIME) plays a crucial role in tumor progression, metastasis, and therapeutic response. Despite several noninvasive strategies have emerged for cancer diagnosis and prognosis, there are still lack of effective radiomic-based model to evaluate TIME status, let alone predict clinical outcome and immune checkpoint inhibitor (ICIs) response for hepatocellular carcinoma (HCC). In this study, we developed a radiomic model to evaluate TIME status within the tumor and predict prognosis and immunotherapy response. A total of 301 patients who underwent magnetic resonance imaging (MRI) examinations were enrolled in our study. The intra-tumoral expression of 17 immune-related molecules were evaluated using co-detection by indexing (CODEX) technology, and we construct Immunoscore (IS) with the least absolute shrinkage and selection operator (LASSO) algorithm and Cox regression method to evaluate TIME. Of 6115 features extracted from MRI, five core features were filtered out, and the Radiomic Immunoscore (RIS) showed high accuracy in predicting TIME status in testing cohort (area under the curve = 0.753). More importantly, RIS model showed the capability of predicting therapeutic response to anti-programmed cell death 1 (PD-1) immunotherapy in an independent cohort with advanced HCC patients (area under the curve = 0.731). In comparison with previously radiomic-based models, our integrated RIS model exhibits not only higher accuracy in predicting prognosis but also the potential guiding significance to HCC immunotherapy. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-023-00136-8.

7.
Front Oncol ; 12: 986713, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505850

RESUMO

Purpose: The present study aimed to determine the reliable imaging features to distinguish atypical hepatocellular carcinoma (HCC) with peripheral rim-like enhancement from intrahepatic mass-forming cholangiocarcinoma (IMCC) on contrast-enhanced magnetic resonance imaging (MRI). Methods: A total of 168 patients (130 male, 57.10 ± 10.53 years) pathological confirmed HCC or IMCC who underwent contrast-enhanced MRI between July 2019 and February 2022 were retrospectively included. Univariate and multivariate logistic regression analyses were used to determine independent differential factors for distinguishing HCC from IMCC, and the model was established. Bootstrap resampling 1000 times was used to verify the model, which was visualized by nomograms. The predictive performance of the model was evaluated based on discrimination, calibration, and clinical utility. Results: Radiological capsule (OR 0.024, 95% CI: 0.006, 0.095, P<0.001), heterogeneous signal intensity (SI) on T1WI (OR 0.009, 95%CI: 0.001,0.056, P<0.001) were independent differential factors for predicting HCC over IMCC. A lobulated contour (OR 11.732, 95%CI: 2.928,47.007, P = 0.001), target sign on DP (OR 14.269, 95%CI: 2.849,82.106, P = 0.007), bile duct dilatation (OR 12.856, 95%CI: 2.013, P = 0.001) were independent differential factors for predicting IMCCs over HCCs. The independent differential factors constituted a model to distinguish atypical HCCs and IMCCs. The area under receiver operating characteristic (ROC) curve, sensitivity, and specificity values of the model were 0.964(0.940,0.987), 0.88, and 0.906, indicating that the model had an excellent differential diagnostic performance. The decision curve analysis (DCA) curve showed that the model obtained a better net clinical benefit. Conclusion: The present study identified reliable imaging features for distinguishing atypical HCCs with peripheral rim-like enhancement from IMCCs on contrast-enhanced MRI. Our findings may help radiologists provide clinicians with more accurate preoperative imaging diagnoses to select appropriate treatment options.

8.
Front Oncol ; 12: 992301, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110937

RESUMO

Purpose: The present study aimed to develop and validate a preoperative model based on gadobenate-enhanced magnetic resonance imaging (MRI) for predicting microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) size of ≤5 cm. In order to provide preoperative guidance for clinicians to optimize treatment options. Methods: 164 patients with pathologically confirmed HCC and preoperative gadobenate-enhanced MRI from July 2016 to December 2020 were retrospectively included. Univariate and multivariate logistic regression (forward LR) analyses were used to determine the predictors of MVI and the model was established. Four-fold cross validation was used to verify the model, which was visualized by nomograms. The predictive performance of the model was evaluated based on discrimination, calibration, and clinical utility. Results: Elevated alpha-fetoprotein (HR 1.849, 95% CI: 1.193, 2.867, P=0.006), atypical enhancement pattern (HR 3.441, 95% CI: 1.523, 7.772, P=0.003), peritumoral hypointensity on HBP (HR 7.822, 95% CI: 3.317, 18.445, P<0.001), and HBP hypointensity (HR 3.258, 95% CI: 1.381, 7.687, P=0.007) were independent risk factors to MVI and constituted the HBP model. The mean area under the curve (AUC), sensitivity, specificity, and accuracy values for the HBP model were as follows: 0.830 (95% CI: 0.784, 0.876), 0.71, 0.78, 0.81 in training set; 0.826 (95% CI:0.765, 0.887), 0.8, 0.7, 0.79 in test set. The decision curve analysis (DCA) curve showed that the HBP model achieved great clinical benefits. Conclusion: In conclusion, the HBP imaging features of Gd-BOPTA-enhanced MRI play an important role in predicting MVI for HCC. A preoperative model, mainly based on HBP imaging features of gadobenate-enhanced MRI, was able to excellently predict the MVI for HCC size of ≤5cm. The model may help clinicians preoperatively assess the risk of MVI in HCC patients so as to guide clinicians to optimize treatment options.

9.
Front Oncol ; 12: 862967, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992871

RESUMO

Purpose: The purpose of this study was to establish a model for predicting early recurrence (≤2 years) of hepatocellular carcinoma (HCC) after anatomical hepatectomy based on the hepatobiliary phase (HBP) imaging characteristics of gadobenate-enhanced MRI. Methods: A total of 155 patients who underwent anatomical hepatectomy HCC therapy and gadobenate-enhanced MRI were included retrospectively. The patients were divided into the early recurrence-free group (n = 103) and the early recurrence group (n = 52). Univariate and multivariate Cox regression analysis was used to determine the independent risk factors related to early recurrence, and four models were established. The preoperative model with/without HBP imaging features (HBP-pre/No HBP-pre model) and the postoperative model with/without HBP imaging features (HBP-post/No HBP-post model). Bootstrap resampling 1,000 times was used to verify the model and displayed by nomograms. The performance of nomograms was evaluated by discrimination, calibration, and clinical utility. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to evaluate the differences between models and to select the optimal model. Results: Shape, arterial peritumoral enhancement, AFP-L3, and peritumoral hypointensity on HBP were identified as independent risk factors. Prothrombin time (PT) and r-glutamyltransferase (GGT) were selected by multivariate Cox regression. These six factors construct the HBP-pre model. Removing peritumoral hypointensity on HBP was the No HBP-pre model. Adding microvascular invasion (MVI) and microscopic capsule factors were the HBP-post and No HBP-post model. The C-index was 0.766, 0.738, 0.770, and 0.742, respectively. The NRI and IDI of the HBP-pre vs. the No HBP-pre model and the HBP-post vs. the No HBP-post model significantly increased 0.258, 0.092, 0.280, and 0.086, respectively. The calibration curve and decision curve analysis (DCA) had good consistency and clinical utility. However, the NRI and IDI of the No HBP-post vs. the No HBP-pre model and the HBP-post vs. the HBP-pre model did not increase significantly. Conclusions: Preoperative gadobenate-enhanced MR HBP imaging features significantly improve the model performance while the postoperative pathological factors do not. Therefore, the HBP-pre model is selected as the optimal model. The strong performance of this model may help hepatologists to assess the risk of recurrence in order to guide the selection of treatment options.

10.
Syst Biol Reprod Med ; 66(4): 244-254, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32427532

RESUMO

Cryopreservation can induce damage in human spermatozoa through reactive oxygen species (ROS) generation. To reduce the potential risk of oxidative stress-induced sperm DNA damage, addition of different epigallocatechin-3-gallate (EGCG) concentrations were performed to determine the optimum concentration which was beneficial for IVF outcome for both fresh and frozen-thawed sperm. Next, the mouse sperm model exhibiting oxidative stress-induced DNA damage by exogenously treating with H2O2 but overcoming the low fertilization rate of frozen-thawed sperm was used to investigate the effect of EGCG on the embryonic development and the potential EGCG-mediated effects on ataxia telangiectasia mutated (ATM) pSer-1981 in zygotes, the latter was known for leading to the activation of major kinases involved in the DNA repair pathway and the cell cycle checkpoint pathway. We found the fertilization and embryonic development of embryos inseminated with frozen-thawed sperm was impaired compared to fresh sperm. EGCG promoted the development of embryos inseminated with both types of sperm at optimum concentration. In embryos inseminated with the H2O2 sperm, fertilization, embryonic development, and the time at which the cleavage rate of one-cell embryos reached ≥95% were not affected by EGCG treatment. However, the EGCG-treated group required less time to achieve 50% cleavage rate of one-cell embryos, and the EGCG-treated zygotes showed enhanced expression of ATM (pSer-1981) than the untreated group. EGCG at optimum concentrations may exert beneficial effects by modulating the ATM activation and moving up the time to enter into mitotic (M) phase. ABBREVIATIONS: ROS: reactive oxygen species; EGCG: epigallocatechin-3-gallate; ATM: ataxia telangiectasia mutated; M: mitotic.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Dano ao DNA , Fertilização in vitro , Espermatozoides/efeitos dos fármacos , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Catequina/farmacologia , Criopreservação , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Peróxido de Hidrogênio/farmacologia , Masculino , Camundongos , Estresse Oxidativo , Gravidez , Preservação do Sêmen , Espermatozoides/fisiologia
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(1): 20-26, 2020 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-32376564

RESUMO

OBJECTIVE: To investigate the effect of overexpression of leukemia inhibitory factor (LIF) on cisplatin and paclitaxel resistance of endometrial cancer cells in vitro. METHODS: Endometrial cancer cell lines HEC-1B and RL95-2 were infected with a recombinant lentivirus to overexpress LIF, and the changes in LIF expression was verified using RT-qPCR and ELISA. The viability of the LIF-overexpressing cells was assessed using CCK-8 assay, and the cell apoptosis and changes in mitochondrial membrane potential in response to cisplatin or paclitaxel treatment were analyzed with annexin V-FITC/PI staining and JC-1 assay, respectively. The effect of LIF overexpression on the expressions of Bcl-2 family proteins and STAT3 pathway was evaluated using Western blotting; dual-luciferase reporter gene assay was employed to detect the transcriptional activity of STAT3. The effect of STAT3 silencing on apoptosis of the LIF-overexpressing cells induced by cisplatin or paclitaxel was investigated. RESULTS: The cell lines infected with the recombinant lentivirus showed significantly increased mRNA and protein levels of LIF (P < 0.05) without obvious changes in the cell viability (P>0.05). LIF overexpression significantly attenuated cisplatin-or paclitaxel-induced apoptosis of the endometrial cancer cells (P < 0.05) and markedly increased mitochondrial membrane potential of the cells (P < 0.05). The expressions of Bcl-2, Bcl-xL and p-STAT3 proteins increased obviously while the expressions of Bax, Bad and STAT3 either decreased or showed no obvious changes in the LIF-overexpressing cells. Overexpressing LIF significantly enhanced the transcriptional activity of STAT3 (P < 0.05), and silencing STAT3 obviously enhanced apoptosis of the endometrial cancer cells overexpressing LIF (P < 0.05). CONCLUSIONS: s Overexpression of LIF can enhance cisplatin and paclitaxel resistance to endometrial cancer cells in vitro.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias do Endométrio/genética , Fator Inibidor de Leucemia/genética , Paclitaxel/farmacologia , Transdução de Sinais , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteína bcl-X/metabolismo
12.
Mol Ther Oncolytics ; 14: 94-106, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31193124

RESUMO

Leucine-rich-repeat-containing G protein-coupled receptors (LGRs) have been widely found to be implicated with development and progression in multiple cancer types. However, the clinical significance and biological functions of LGR6 in ovarian cancer remains unclear. In this study, LGR6 expression was mainly examined by immunohistochemistry. Functional assays in vitro and animal experiments in vivo were carried out to explore the effect of LGR6 on cancer stem cell (CSC) characteristics and chemotherapeutic responses in ovarian cancer cells. Luciferase assays and GSEA were used to discern the underlying mechanisms contributing to the roles of LGR6 in ovarian cancer. Here, we reported that LGR6 was upregulated in ovarian cancer, which positively correlated with poor chemotherapeutic response and progression survival in ovarian cancer patients. Loss-of-function assays showed that downregulating LGR6 abrogated the CSC-like phenotype and chemoresistance in vitro. More importantly, silencing LGR6 improved the chemoresistance of ovarian cancer cells to cisplatin in vivo. Mechanistic investigation further revealed that silencing LGR6 inhibited stemness and chemoresistance by repressing Wnt/ß-catenin signaling. Collectively, our results uncover a novel mechanism contributing to LGR6-induced chemotherapeutic resistance in ovarian cancer, providing the evidence for LGR6 as a potential therapeutic target in ovarian cancer.

13.
Zhonghua Nan Ke Xue ; 16(4): 349-53, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20626166

RESUMO

Male germ cells are particularly susceptible to DNA damage by genotoxic agents during spermiogenesis and spermatozoal maturation, and meanwhile lack an effective repair system to eliminate the lesions. Because the DNA damaged sperm still has fertilizability and developmental potentiality, damage repair may occur after fertilization, but its mechanism remains unknown. Histone H2AX phosphorylation (gammaH2AX) is reportedly involved in the repair of damaged sperm DNA after fertilization. This review aims to summarize the present knowledge on the mechanism of gammaH2AX-mediated repair of DNA damaged sperm in the zygote.


Assuntos
Reparo do DNA , Histonas/metabolismo , Espermatozoides/patologia , Zigoto , Dano ao DNA , Humanos , Masculino , Fosforilação
14.
J Androl ; 31(5): 437-44, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19834132

RESUMO

Human semen cryopreservation in the clinical management of male infertility is complicated by cryodamage to spermatozoa. We aimed to clarify the full pattern of cryodamage and evaluate the protective effects of ascorbate and catalase on cryopreserved spermatozoa. Semen samples were collected from 30 fertile males. Each sample was divided into 6 groups: fresh semen, cryopreserved semen without treatment, and samples cryopreserved with ascorbate (300 or 600 µM) or catalase (200 or 400 IU/mL). Spermatozoa were examined for their viability, motility, reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), apoptosis (positive for annexin V and negative for propidium iodide [ie, Ann(+)/PI(-)]), and DNA damage (Olive tail moment [OTM]) in the presence or absence of ascorbate or catalase during cryopreservation. In comparison with the fresh spermatozoa, there was a significant decrease in the viability, motility, and MMP but increase in Ann(+)/PI(-) and OTM in the cryopreserved spermatozoa (P < .01 and P < .05, respectively). Concurrently, ROS levels in the postthaw spermatozoa also increased significantly, and this elevation was well correlated with the quality variations of postthaw spermatozoa (P < .01 for all). Ascorbate (300 µM) and catalase (200 and 400 IU/mL) reduced the ROS levels in postthaw spermatozoa significantly, compared with those in the control (P < .05). Furthermore, these antioxidants also prevented those characteristics from being adversely affected (P < .05). This study demonstrated that cryopreservation results in cryodamage to human spermatozoa, possibly through the mechanism of ROS. Appropriate ascorbate or catalase supplementation of cryoprotective medium restrains ROS levels and the resultant cryodamage.


Assuntos
Ácido Ascórbico/farmacologia , Catalase/farmacologia , Criopreservação/métodos , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos , Adulto , Antioxidantes/farmacologia , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Análise do Sêmen
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