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1.
Int J Mol Sci ; 24(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37958873

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is defined as the accumulation of lipids in the form of lipid droplets in more than 5% of hepatocytes. It is regarded as a range of diverse pathologies, including simple steatosis and steatohepatitis. The structural characteristics of lipid droplets, along with their protein composition, mainly including perilipins, have been implicated in the etiology of the disease. These proteins have garnered increasing attention as a pivotal regulator since their levels and distinct expression appear to be associated with the progression from simple steatosis to steatohepatitis. Perilipins are target proteins of chaperone-mediated autophagy, and their degradation is a prerequisite for lipolysis and lipophagy to access the lipid core. Both lipophagy and chaperone-mediated autophagy have significant implications on the development of the disease, as evidenced by their upregulation during the initial phases of simple steatosis and their subsequent downregulation once steatosis is established. On the contrary, during steatohepatitis, the process of chaperone-mediated autophagy is enhanced, although lipophagy remains suppressed. Evidently, the reduced levels of autophagic pathways observed in simple steatosis serve as a defensive mechanism against lipotoxicity. Conversely, in steatohepatitis, chaperone-mediated autophagy fails to compensate for the continuous generation of small lipid droplets and thus cannot protect hepatocytes from lipotoxicity.


Asunto(s)
Autofagia Mediada por Chaperones , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Gotas Lipídicas/metabolismo , Metabolismo de los Lípidos , Hepatocitos/metabolismo , Autofagia/fisiología , Perilipinas/metabolismo , Hígado/metabolismo
3.
Antioxidants (Basel) ; 12(6)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37371999

RESUMEN

Hepatocellular carcinoma (HCC) represents a worryingly increasing cause of malignancy-related mortality, while Metabolic Associated Fatty Liver Disease (MAFLD) is going to become its most common cause in the next decade. Understanding the complex underlying pathophysiology of MAFLD-related HCC can provide opportunities for successful targeted therapies. Of particular interest in this sequela of hepatopathology is cellular senescence, a complex process characterised by cellular cycle arrest initiated by a variety of endogenous and exogenous cell stressors. A key biological process in establishing and maintaining senescence is oxidative stress, which is present in multiple cellular compartments of steatotic hepatocytes. Oxidative stress-induced cellular senescence can change hepatocyte function and metabolism, and alter, in a paracrine manner, the hepatic microenvironment, enabling disease progression from simple steatosis to inflammation and fibrosis, as well as HCC. The duration of senescence and the cell types it affects can tilt the scale from a tumour-protective self-restricting phenotype to the creator of an oncogenic hepatic milieu. A deeper understanding of the mechanism of the disease can guide the selection of the most appropriate senotherapeutic agent, as well as the optimal timing and cell type targeting for effectively combating HCC.

4.
Cancers (Basel) ; 15(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37173975

RESUMEN

BACKGROUND: Intraoperative Flow Cytometry (iFC) is a novel technique for the assessment of the grade of malignancy and the diagnosis of tumor type and resection margins during solid tumor surgery. Herein, we set out to analyze the role of iFC in the grading of gliomas and the evaluation of resection margins. MATERIAL AND METHODS: iFC uses a fast cell cycle analysis protocol (Ioannina Protocol) that permits the analysis of tissue samples within 5-6 min. Cell cycle analysis evaluated the G0/G1 phase, S-phase, mitosis, and tumor index (S + mitosis phase fraction) and ploidy status. In the current study, we evaluated tumor samples and samples from the peripheral borders from patients with gliomas who underwent surgery over an 8-year period. RESULTS: Eighty-one patients were included in the study. There were sixty-eight glioblastoma cases, five anaplastic astrocytomas, two anaplastic oligodendrogliomas, one pilocytic astrocytoma, three oligodendrogliomas and two diffuse astrocytomas. High-grade gliomas had a significantly higher tumor index than low grade gliomas (median value 22 vs. 7.5, respectively, p = 0.002). Using ROC curve analysis, a cut-off value of 17% in the tumor index could differentiate low- from high-grade gliomas with a 61.4% sensitivity and 100% specificity. All low-grade gliomas were diploid. From the high-grade gliomas, 22 tumors were aneuploid. In glioblastomas, aneuploid tumors had a significantly higher tumor index (p = 0.0018). Twenty-three samples from glioma margins were evaluated. iFC verified the presence of malignant tissue in every case, using histology as the gold standard. CONCLUSION: iFC constitutes a promising intraoperative technique for glioma grading and resection margin assessment. Comparative studies with additional intraoperative adjuncts are necessary.

6.
Curr Oncol ; 30(1): 832-838, 2023 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-36661712

RESUMEN

Meningiomas are the most frequent central nervous system tumors in adults. The majority of these tumors are benign. Nevertheless, the intraoperative identification of meningioma grade is important for modifying surgical strategy in order to reduce postoperative complications. Here, we set out to investigate the role of intraoperative flow cytometry for the differentiation of low-grade (grade 1) from high-grade (grade 2-3) meningiomas. The study included 59 patients. Intraoperative flow cytometry analysis was performed using the 'Ioannina Protocol' which evaluates the G0/G1 phase, S-phase, mitosis and tumor index (S + mitosis phase fraction) of a tumor sample. The results are available within 5 min of sample receipt. There were 41 grade 1, 15 grade 2 and 3 grade 3 meningiomas. High-grade meningiomas had significantly higher S-phase fraction, mitosis fraction and tumor index compared to low-grade meningiomas. High-grade meningiomas had significantly lower G0/G1 phase fraction compared to low-grade meningiomas. Thirty-eight tumors were diploids and twenty-one were aneuploids. No significant difference was found between ploidy status and meningioma grade. ROC analysis indicated 11.4% of tumor index as the optimal cutoff value thresholding the discrimination between low- and high-grade meningiomas with 90.2% sensitivity and 72.2% specificity. In conclusion, intraoperative flow cytometry permits the detection of high-grade meningiomas within 5 min. Thus, surgeons may modify tumor removal strategy.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Adulto , Humanos , Meningioma/cirugía , Meningioma/patología , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/patología , Citometría de Flujo , Aneuploidia
7.
Cancers (Basel) ; 14(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36428728

RESUMEN

Tumor-infiltrating lymphocytes (TILs) contribute to breast cancer (BC) prognosis. We investigated the prognostic impact of CD8+ TILs in patients with early breast cancer treated with adjuvant chemotherapy in a large observational clinical trial. Along with a 10 year follow-up, considering the efficacy and safety, we report the results of the translational part of our study. We examined the patients' tumors for total (t), stromal (s), and intratumoral (i) CD8 lymphocyte density (counts/mm2) on tissue-microarray cores. The impact of CD8+ TILs counts on DFS and OS, and its correlation with breast cancer subtypes and standard clinicopathological parameters, were investigated, along with efficacy and safety data. Among the 928 eligible patients, 627 had available CD8+ data. Of which, 24.9% had a high expression of sCD8, iCD8, and total CD8, which were correlated with higher Ki67, TILs density, ER/PgR negativity, and higher histological grade. The 5year DFS and OS rates were 86.1% and 91.4%, respectively. Patients with high iCD8 and tCD8 had longer DFS and OS compared to those with low counts/mm2 (DFS: HR = 0.58, p = 0.011 and HR = 0.65, p = 0.034 and OS: HR = 0.63, p = 0.043 and HR = 0.58, p = 0.020, respectively). Upon adjustment for clinicopathological parameters, iCD8 and tCD8 retained their favorable prognostic significance for DFS and OS, whereas high sCD8 was only prognostic for DFS. Menopausal status, tumor size, and nodal status retained their prognostic significance in all examined multivariate models. CD8+ TILs, and especially their intratumoral subset, represent a potential favorable prognostic factor in early BC.

8.
Eur Radiol ; 32(11): 7522-7531, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35484338

RESUMEN

OBJECTIVES: To explore the association between testicular volumetric apparent diffusion coefficient (ADC) histogram analysis metrics and histologic categories in nonobstructive azoospermia (NOA). The role of ADC histogram analysis in predicting the presence of spermatozoa, prior to testicular sperm extraction (TESE), was also investigated. METHODS: Forty-one NOA men and 17 age-matched controls underwent scrotal MRI with diffusion-weighted imaging. Histogram analysis of ADC data of the whole testis was performed. Metrics including mean, standard deviation, median, mode, 25th percentile, 75th percentile, skewness, kurtosis, and entropy of volumetric ADC histograms were calculated. Nonparametric statistical tests were used to assess differences in ADC histogram parameters between NOA histologic categories (hypospermatogenesis, severe hypospermatogenesis, early maturation arrest, and Sertoli cell-only syndrome) and normal testes and, between NOA with positive and negative sperm retrieval. RESULTS: Normal testes had a lower mean, median, mode, 25th percentile (p < 0.001), and 75th percentile of ADC (p = 0.001), compared to NOA histologic phenotypes. NOA with hypospermatogenesis had a lower 25th percentile of ADC compared to NOA with severe hypospermatogenesis. Regression analysis revealed that the 25th percentile of ADC had a moderately negative correlation with NOA histologic phenotype. The median ADC proved the most significant metric (p = 0.007) to predict the presence of sperm. CONCLUSIONS: Testicular volumetric ADC histogram parameters may contribute in the identification of the subpopulation of NOA men with a specific type of spermatogenic arrest. KEY POINTS: • Volumetric ADC histogram analysis metrics may be used as noninvasive markers of impaired spermatogenesis in nonobstructive azoospermia. • The 25th percentile of ADC proved useful in discriminating between NOA testes with hypospermatogenesis and severe hypospermatogenesis. • The median ADC proved the most significant parameter to predict the presence of viable spermatozoa prior to TESE.


Asunto(s)
Azoospermia , Infertilidad Masculina , Oligospermia , Humanos , Masculino , Azoospermia/diagnóstico por imagen , Azoospermia/patología , Testículo/diagnóstico por imagen , Testículo/patología , Oligospermia/patología , Estudios Retrospectivos , Semen , Espermatogénesis
9.
Cancers (Basel) ; 14(3)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35159028

RESUMEN

Hepatocarcinogenesis is a long process with a complex pathophysiology. The current therapeutic options for HCC management, during the advanced stage, provide short-term survival ranging from 10-14 months. Autophagy acts as a double-edged sword during this process. Recently, two main autophagic pathways have emerged to play critical roles during hepatic oncogenesis, macroautophagy and chaperone-mediated autophagy. Mounting evidence suggests that upregulation of macroautophagy plays a crucial role during the early stages of carcinogenesis as a tumor suppressor mechanism; however, it has been also implicated in later stages promoting survival of cancer cells. Nonetheless, chaperone-mediated autophagy has been elucidated as a tumor-promoting mechanism contributing to cancer cell survival. Moreover, the autophagy pathway seems to have a complex role during the metastatic stage, while induction of autophagy has been implicated as a potential mechanism of chemoresistance of HCC cells. The present review provides an update on the role of autophagy pathways in the development of HCC and data on how the modulation of the autophagic pathway could contribute to the most effective management of HCC.

10.
Ann Med Surg (Lond) ; 72: 103043, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34868572

RESUMEN

INTRODUCTION AND IMPORTANCE: Metronomic chemotherapy entails chronic, equally spaced administration of low doses of various chemotherapeutic drugs without extended rest periods. Its use as a second-line treatment in advanced or metastatic hepatocellular cancer remains under investigation. CASE PRESENTATION: We report a case of a 49-year-old Caucasian female patient with an enlarged (∼14 cm) hepatocellular cancer. In July 2016, she underwent right hepatectomy (after preceding TACE). During the follow-up period, she presented early disease recurrence with lung and peritoneal metastasis. Initially, she received an inhibitor of protein kinase (sorafenib) for six months without response. Afterwards, cyclophosphamide administration at low doses as metronomic chemotherapy provided complete regression of the metastatic lesions. The patient remains in good performance status almost 4 years after initial treatment, without signs of recurrence in her recent follow-up. CLINICAL DISCUSSION: Using cyclophosphamide as metronomic chemotherapy in advanced hepatocellular cancer may have a promising antiangiogenic antitumor effect. Future clinical trials need to demonstrate this effect in terms of tumor suppression and increased disease-free survival. CONCLUSION: Large multi-centered clinical trials have to be planned to investigate the precise role of cyclophosphamide in the therapy of hepatocellular cancer while defining the patients' profile that will benefit most from cyclophosphamide.

11.
Methods Protoc ; 4(3)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34564312

RESUMEN

Liver resection is the main treatment for primary and metastatic liver tumors in order to achieve long-term survival with good quality of life. The ultimate goal of surgical oncology is to achieve complete tumor removal with adequate clear surgical margins. Flow cytometry is a powerful analytical technique with applications such as phenotypic analysis and quantification of DNA content. Intraoperative flow cytometry (iFC) is the application of flow cytometry for DNA content/ploidy and cell cycle distribution analysis during surgery for tumor cell analysis and margin evaluation. It has been used for cell analysis of intracranial tumors and recently of head and neck carcinomas and breast carcinomas, as well as for tumor margin evaluation. Herein, we present a novel touch imprint iFC protocol for the detailed assessment of tumor margins during excision of malignant hepatic lesions. The protocol aims to offer information on surgical margins after removal of malignant liver tumors based on DNA content of cancer cells and to corroborate the results of iFC with that of histopathological analysis. Based on the established role of iFC in other types of malignancies, our specialized protocol has the potential, through characterization of cells in liver transection surface post hepatectomy, to offer significant information on the type of resection and tumor biology. This information can be used to effectively guide intra- and postoperative patient management.

12.
In Vivo ; 35(1): 333-339, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33402482

RESUMEN

BACKGROUND/AIM: The mechanisms underlying the contribution of the heparan sulfate proteoglycan syndecan-1 to liver tissue injury and to crucial biological processes, such as fibrogenesis, remain to be elucidated. Therefore, we investigated the immunohistochemical expression of syndecan-1 in chronic liver diseases (CLDs) and its probable role in hepatic fibrosis. MATERIALS AND METHODS: Immunohistochemistry was performed on formalin-fixed, paraffin-embedded tissue sections of biopsy material obtained from 128 patients diagnosed with CLDs. The correlation between syndecan-1 expression and the stage of fibrosis was investigated. RESULTS: According to the severity of fibrosis, cases were categorized into three groups: early fibrosis; intermediate fibrosis; advanced fibrosis. Syndecan-1 expression was significantly enhanced in advanced fibrosis compared to early (p<0.012) and intermediate (p<0.003) fibrosis. CONCLUSION: In CLDs, syndecan-1 immunohisto-chemical overexpression was found to be positively correlated with the severity of fibrosis, suggesting its probable role in hepatic fibrogenesis.


Asunto(s)
Glicoproteínas de Membrana , Sindecano-1 , Humanos , Inmunohistoquímica , Cirrosis Hepática/genética , Sindecano-1/genética
13.
Front Physiol ; 12: 801340, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35185602

RESUMEN

Chronic liver injury, regardless of the underlying disease, results in gradual alteration of the physiological hepatic architecture and in excessive production of extracellular matrix, eventually leading to cirrhosis Liver cellular architecture consists of different cell populations, among which hepatic stellate cells (HSCs) have been found to play a major role in the fibrotic process. Under normal conditions, HSCs serve as the main storage site for vitamin A, however, pathological stimuli lead to their transdifferentiation into myofibroblast cells, with autophagy being the key regulator of their activation, through lipophagy of their lipid droplets. Nevertheless, the role of autophagy in liver fibrosis is multifaceted, as increased autophagic levels have been associated with alleviation of the fibrotic process. In addition, it has been found that HSCs receive paracrine stimuli from neighboring cells, such as injured hepatocytes, Kupffer cells, sinusoidal endothelial cells, which promote liver fibrosis. These stimuli have been found to be transmitted via exosomes, which are incorporated by HSCs and can either be degraded through lysosomes or be secreted back into the extracellular space via fusion with the plasma membrane. Furthermore, it has been demonstrated that autophagy and exosomes may be concomitantly or reciprocally regulated, depending on the cellular conditions. Given that increased levels of autophagy are required to activate HSCs, it is important to investigate whether autophagy levels decrease at later stages of hepatic stellate cell activation, leading to increased release of exosomes and further propagation of hepatic fibrosis.

14.
Clin Neurol Neurosurg ; 175: 54-56, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30384116

RESUMEN

Teratomas involving the spinal cord are very rare tumors that affect more commonly children than adult. We report a rare case of an intradural extramedullary teratoma arising in the region of conus medullaris in a previously healthy adult patient. The lesion was totally excised and the postsurgical outcome was favorable. Teratomas should be taken into consideration in the differential diagnosis in previously healthy adults with sudden onset of lower back pain or neurological deficits of the lower extremities and with a tumoral lesion of the spinal cord. Total surgical excision is the indicative treatment of choice.


Asunto(s)
Neoplasias de la Médula Espinal/diagnóstico por imagen , Neoplasias de la Médula Espinal/cirugía , Teratoma/diagnóstico por imagen , Teratoma/cirugía , Adulto , Diagnóstico Diferencial , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Masculino , Neoplasias de la Médula Espinal/complicaciones , Teratoma/complicaciones
15.
Anticancer Res ; 38(7): 3985-3988, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29970521

RESUMEN

BACKGROUND/AIM: Since most cancers are associated with alterations of the p53 and Rb pathways, the expression of p53, p21, Rb, p16, p27, cyclin D1, cyclin A, cyclin B1 and Ki67 proteins were analyzed in bladder urothelial carcinomas (BUC). MATERIALS AND METHODS: One hundred twenty-two cases of BUC were studied by immunohistochemistry. RESULTS: The pathways p53/p21 and Rb/p16/cyclin D1 exhibited alterations in 81/115 and 63/84 cases, respectively. Alterations of the p53/p21 and Rb/p16/cyclin D1 pathways were positively correlated with high cyclin A expression. High expression of p53, Ki67, cyclin A and cyclin B1 was inversely correlated with the papillary morphology of the tumor and positively with tumor grade and T-stage. CONCLUSION: The results showed that a) alterations of the p53 and Rb pathways are associated with high proliferation of tumor cells in BUC and b) high expression of cell-cycle proteins is associated with adverse histopathological parameters of these tumors.


Asunto(s)
Proliferación Celular/genética , Proteína de Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Humanos , Inmunohistoquímica , Neoplasias de la Vejiga Urinaria/metabolismo
17.
J Comput Assist Tomogr ; 37(3): 450-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23674020

RESUMEN

OBJECTIVE: The objective of this study was to assess the accuracy of multidetector computed tomography (CT) in diagnosing perinephric (PN) and/or renal sinus (RS) fat invasion in patients with renal cell carcinoma (RCC), with reference to the CT findings predictive for the diagnosis of invasion. METHODS: This was a retrospective study of 48 RCCs. Examinations were performed on a 16-row CT scanner, including unenhanced and 3-phase contrast-enhanced CT scanning. Unenhanced transverse images and multiplanar reformations of each contrast-enhanced CT phase were evaluated. The predictive value of CT findings in diagnosing PN and/or RS fat invasion was determined using multivariate logistic regression analysis. RESULTS: The CT findings that were most predictive for the diagnosis of PN fat invasion were the presence of contrast-enhancing nodules in the PN fat and tumoral margins. Invasion of the pelvicaliceal system was the most significant predictor in the diagnosis of RS fat invasion. CONCLUSIONS: Multidetector CT provides satisfactory results in detecting PN and/or RS fat invasion in RCC.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Carcinoma de Células Renales/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Tejido Adiposo/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/patología , Distribución de Chi-Cuadrado , Medios de Contraste , Femenino , Humanos , Neoplasias Renales/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Estadísticas no Paramétricas
18.
Bull Acad Natl Med ; 196(3): 705-15; discussion 715-6, 2012 Mar.
Artículo en Francés | MEDLINE | ID: mdl-23472358

RESUMEN

Colorectal adenocarcinomas were long thought to be an homogeneous entity, in which traditional adenomas of the colon were the best-recognized and most common precursor lesions. Current morphological and molecular data suggest an alternative pathway of colorectal carcinogenesis involving "serrated neoplasia". This pathway seems to be responsible for approximately 10% to 15% of sporadic colorectal adenocarcinomas. These serrated lesions, that may progress to cancer, show relatively distinct histopathological molecular and epigenetic features not commonly seen in traditional adenomas. Key characteristics of the serrated neoplasia pathway include BRAF gene mutations, excess CpG island methylation, and subsequent microsatellite instability. A major challenge for pathologists is to identify these new potential precursor lesions, in order to enable early diagnosis and treatment.


Asunto(s)
Adenocarcinoma/etiología , Neoplasias Colorrectales/etiología , Adenocarcinoma/patología , Neoplasias Colorrectales/patología , Humanos
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