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1.
Braz. j. med. biol. res ; 53(2): e9106, 2020. graf
Article in English | LILACS | ID: biblio-1055491

ABSTRACT

Reperfusion strategies in acute myocardial infarction (AMI) can cause a series of additional clinical damage, defined as myocardial ischemia/reperfusion (I/R) injury, and thus there is a need for effective therapeutic methods to attenuate I/R injury. miR-26a-5p has been proven to be an essential regulator for biological processes in different cell types. Nevertheless, the role of miR-26a-5p in myocardial I/R injury has not yet been reported. We established an I/R injury model in vitro and in vivo. In vitro, we used cardiomyocytes to simulate I/R injury using hypoxia/reoxygenation (H/R) assay. In vivo, we used C57BL/6 mice to construct I/R injury model. The infarct area was examined by TTC staining. The level of miR-26a-5p and PTEN was determined by bioinformatics methods, qRT-PCR, and western blot. In addition, the viability and apoptosis of cardiomyocytes were separately detected by MTT and flow cytometry. The targeting relationship between miR-26a-5p and PTEN was analyzed by the TargetScan website and luciferase reporter assay. I/R and H/R treatment induced myocardial tissue injury and cardiomyocyte apoptosis, respectively. The results showed that miR-26a-5p was down-regulated in myocardial I/R injury. PTEN was found to be a direct target of miR-26a-5p. Furthermore, miR-26a-5p effectively improved viability and inhibited apoptosis in cardiomyocytes upon I/R injury by inhibiting PTEN expression to activate the PI3K/AKT signaling pathway. miR-26a-5p could protect cardiomyocytes against I/R injury by regulating the PTEN/PI3K/AKT pathway, which offers a potential approach for myocardial I/R injury treatment.


Subject(s)
Animals , Rabbits , Myocardial Reperfusion Injury/metabolism , Myocardial Ischemia/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Myocytes, Cardiac/pathology , MicroRNAs/metabolism , PTEN Phosphohydrolase/metabolism , Signal Transduction , Blotting, Western , Disease Models, Animal , Proto-Oncogene Proteins c-akt/metabolism , Real-Time Polymerase Chain Reaction , Flow Cytometry , Mice, Inbred C57BL
2.
Biol. Res ; 53: 01, 2020. graf
Article in English | LILACS | ID: biblio-1089072

ABSTRACT

BACKGROUND: Long non-coding RNA small molecule RNA host gene 1 (SNHG1) was previously identified to be relevant with Parkinson's disease (PD) pathogenesis. This work aims to further elucidate the regulatory networks of SNHG1 involved in PD. Methods: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-hydrochloride (MPTP)-induced mice and 1-methyl-4-phenylpyridinium (MPP+)-treated SH-SY5Y cells were respectively constructed as the in vivo and in vitro PD models. Expression levels of SNHG1 and miR-153-3p were detected by qRT-PCR. Protein expression levels of phosphate and tension homology deleted on chromosome ten (PTEN) were measured by western blotting assay. Cell viability and apoptosis were determined by MTT and flow cytometry assays. The interactions among SNHG1, miR-153-3p and PTEN were identified by luciferase reporter assay, RNA immunoprecipitation, and/or RNA pull-down analysis. RESULTS: Increased SNHG1 expression was found in midbrain of MPTP-induced PD mice and MPP+-treated SH-SY5Y cells. Overexpression of SNHG1 lowered viability and enhanced apoptosis in MPP+-treated SH-SY5Y cells. Moreover, SNHG1 acted as a molecular sponge to inhibit the expression of miR-153-3p. Furthermore, miR-153-3p-mediated suppression of MPP+-induced cytotoxicity was abated following SNHG1 up-regulation. Additionally, PTEN was identified as a direct target of miR-153-3p, and SNHG1 could serve as a competing endogenous RNA (ceRNA) of miR-153-3p to improve the expression of PTEN. Besides, enforced expression of PTEN displayed the similar functions as SNHG1 overexpression in regulating the viability and apoptosis of MPP+-treated SH-SY5Y cells. Finally, SNHG1 was found to activate PTEN/AKT/mTOR signaling pathway in SH-SY5Y cells by targeting miR-153-3p. CONCLUSION: SNHG1 aggravates MPP+-induced cellular toxicity in SH-SY5Y cells by regulating PTEN/AKT/mTOR signaling via sponging miR-153-3p, indicating the potential of SNHG1 as a promising therapeutic target for PD.


Subject(s)
Animals , Male , Mice , Parkinson Disease/metabolism , 1-Methyl-4-phenylpyridinium/toxicity , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism , RNA, Long Noncoding/metabolism , Parkinson Disease/genetics , Transfection , Signal Transduction , Cells, Cultured , Gene Expression Regulation , Blotting, Western , Apoptosis , MicroRNAs , Disease Models, Animal , Real-Time Polymerase Chain Reaction , RNA, Long Noncoding/genetics , Mice, Inbred C57BL
3.
Int. j. morphol ; 37(3): 800-804, Sept. 2019. graf
Article in Spanish | LILACS | ID: biblio-1012356

ABSTRACT

El glioblastoma multiforme es el subtipo de gliomas más frecuente en adultos, con una pobre sobrevida promedio posterior al diagnóstico incluso si se aplica el tratamiento óptimo. Se ha estudiado marcadores tumorales de buen pronóstico, siendo controversial la expresión del homólogo de fosfatasa y tensina. Se estudió muestras parafinadas obtenidas de pacientes con glioblastoma multiforme en el Hospital Carlos Van Buren de Valparaíso, Chile, entre 2010 y 2014. Se realizó análisis inmunohistoquímico para expresión de homólogo de fosfatasa y tensina, estudiándose la intensidad y el patrón de expresión en astrocitos y células epiteliales, además de revisión de datos clínicos. Análisis estadístico utilizando SPSS v20. Se estudió la expresión de PTEN en 21 pacientes. Un 52,4 % presentó una baja expresión en núcleos de astrocitos, con un promedio de sobrevida de 14,2 meses comparado con 10,2 meses del grupo con alta expresión (p=0,33). Se encontró una intensa expresión endotelial en tejido tumoral, comparado con tejido cerebral sin tumor. Se encontró una relación entre la expresión nuclear en astrocitos con diferencias en el tiempo de sobrevida, aunque no estadísticamente significativa, requiriéndose nuevos estudios para corroborarlo. La intensa expresión endotelial observada en tejido tumoral debe ser analizada de forma dirigida.


Glioblastoma multiforme is the most frequent glioma subtype in adults, with poor survival rate after diagnosis even applying the optimal treatment. Tumoural markers have been studied looking for good prognosis, being the phosphatase and tensin homologue controversial. Paraffined samples were used from Carlos Van Buren Hospital in Valparaíso, Chile, between 2010 and 2014. An immunohistochemical analysis was performed looking for phosphatase and tensing homologue expression, studying the intensity and expression pattern in astrocytes and epithelial cells, in addition to clinical data. Statistical analysis was performed using SPSS v20. It was studied the phosphatase and tensin homologue expression in 21 patients. In the study, 52,4 % presented low expression in astrocytic glial cell nuclei, with a survival mean of 14.2 months in comparison to 10.2 months in the high expression group (p=0.33). A very intense endothelial expression was found in tumoural tissue, in comparison to the tissue without tumor. A relation between nuclear expression in astrocytes and survival rate was found, although no statistically significant. The intense endothelial expression seen in tumoural tissue must be studied directly.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Young Adult , Brain Neoplasms/metabolism , Glioblastoma/metabolism , Immunohistochemistry , Survival Analysis , Astrocytes/metabolism , Retrospective Studies , PTEN Phosphohydrolase/metabolism
4.
Braz. j. med. biol. res ; 52(12): e8483, 2019. tab, graf
Article in English | LILACS | ID: biblio-1055462

ABSTRACT

PTEN is the most commonly inactivated tumor suppressor gene in primary prostate cancer (PCa) and its loss is associated with poor clinical outcomes. ERG rearrangement is a genomic alteration frequently found in PCa and its prognostic significance has yielded mixed results. Although the association of PTEN and ERG biomarkers has potential impact on clinical outcomes, studies examining the two genes simultaneously are scarce in Brazilian populations. In this study, we retrospectively examined the relationship between ERG expression and PTEN loss in 119 surgically treated prostate cancer patients from Northeastern Brazil through immunohistochemical analysis. ERG expression was found in 41.0% (48/117) of cases and the loss of PTEN detected in 38.1% (40/105) of samples. ERG-positive cases were significantly associated with lower prostate weight; ERG negatively correlated with Gleason score above 6. The lack of associations for PTEN loss alone in this cohort is counter to the literature, which shows that PTEN loss is usually associated with more aggressive disease. The overlapping of the two biomarkers revealed that samples with positive ERG expression without PTEN loss were associated with lower Gleason and lower Grade group. This study contributes with the discussion about the development of the molecular profiling of prostate cancer. The further development of similar studies could help in stratifying specific risk groups, leading to a more personalized therapeutic decision for prostate cancer treatment.


Subject(s)
Humans , Male , Middle Aged , Aged , Aged, 80 and over , Prostatic Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , PTEN Phosphohydrolase/metabolism , Prognosis , Prostatic Neoplasms/surgery , Prostatic Neoplasms/pathology , Immunohistochemistry , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/blood , Prevalence , Retrospective Studies , Cohort Studies , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/blood , Neoplasm Grading , Transcriptional Regulator ERG/genetics , Transcriptional Regulator ERG/metabolism , Transcriptional Regulator ERG/blood
5.
Braz. j. med. biol. res ; 52(7): e8381, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011592

ABSTRACT

Experiments were conducted to determine if the follicle-stimulating hormone (FSH) receptor binding inhibitor (FRBI) impacts the expression levels of AT-rich interactive domain-containing protein 1A (ARID1A) and phosphatase and tensin homolog (PTEN) in ovaries and blood, as well as expressions of follicle-stimulating hormone cognate receptor (FSHR) gene and proteins. Mice in FRBI-10, FRBI-20, FRBI-30, and FRBI-40 groups were intramuscularly injected with 10, 20, 30, and 40 mg FRBI/kg, respectively, for five consecutive days. Western blotting and qRT-PCR were utilized to determine expression levels of ARID1A and PTEN proteins and mRNAs. Serum ARID1A and PTEN concentrations of the FRBI-40 group were higher than the control group (CG) and FSH group (P<0.05). FSHR mRNA levels of FRBI-20, FRBI-30, and FRBI-40 groups were lower than that of CG and FSH groups on day 15 (P<0.05 or P<0.01). Expression levels of FSHR proteins of FRBI-30 and FRBI-40 groups were lower than those of CG and FSH groups (P<0.05). Levels of ARID1A and PTEN proteins of the FRBI-30 group were greater than CG on days 20 and 30 (P<0.05). FRBI doses had significant positive correlations to levels of ARID1A and PTEN proteins. Additionally, ARID1A and PTEN had negative correlations to FSHR mRNAs and proteins. A high dose of FRBI could promote the expression levels of ARID1A and PTEN proteins in ovarian tissues. FRBI increased serum concentrations of ARID1A and PTEN. However, FRBI depressed expression levels of FSHR mRNAs and proteins in mouse ovaries.


Subject(s)
Animals , Female , Rabbits , Ovarian Neoplasms/metabolism , Receptors, FSH/antagonists & inhibitors , Nuclear Proteins/blood , DNA-Binding Proteins/metabolism , PTEN Phosphohydrolase/blood , Follicle Stimulating Hormone/metabolism , Phosphorylation , Transcription Factors , Nuclear Proteins/metabolism , Transcriptional Activation/genetics , Up-Regulation , Blotting, Western , DNA-Binding Proteins/blood , PTEN Phosphohydrolase/metabolism , Real-Time Polymerase Chain Reaction
6.
Appl. cancer res ; 39: 1-6, 2019. ilus, tab
Article in English | LILACS, Inca | ID: biblio-994774

ABSTRACT

Background: PTEN loss is observed in 20­30% of prostate cancers and is associated with a poor outcome, but clinical details of the impact of this biomarker are unclear for intermediate grade tumors. Methods: We investigated 43 radical prostatectomy-derived grade 7 prostate tumors from the Clinics Hospital of Ribeirão Preto. Tissue microarray (TMA) blocks were constructed and PTEN copy number status was determined for all patients through fluorescence in situ hybridization (FISH). To determine the presence of PTEN protein loss in our study cohort, we performed immunohistochemistry (IHC) in TMA sections. We then developed an automated algorithm in HALO™ to identify regions of PTEN protein loss in whole prostate scanned sections from ten patients with known PTEN deletion status by FISH. Clinical analyses were conducted to determine the associations between PTEN loss and patient outcome. All statistical analyses were conducted in R v3.4.3 with P-values below 0.05 being considered statistically significant. Results: In this study of 43 grade 7 tumors, we found PTEN deletions by FISH in 18.9% of tumors, and PTEN protein loss by IHC in 16.3% of tumors. Both techniques were highly concordant and complementary. Clinical analysis demonstrated that PTEN deletion by FISH was significantly associated with positive margin invasion (P = 0.04) and Gleason score upgrade (P = 0.001). Digital image analysis of ten representative tumors demonstrated distinct intratumoral heterogeneity for PTEN protein loss in four tumors. Conclusions: This study shows that PTEN loss in Gleason grade 7 tumors can be heterogeneous and that a systematic analysis of this biomarker using a combination of FISH, IHC, and digital imaging may identify patients with a greater risk of poor outcome (AU)


Subject(s)
Humans , Male , Prostatic Neoplasms/pathology , PTEN Phosphohydrolase/metabolism , Prognosis , Prostatectomy , Prostatic Neoplasms/genetics , Immunohistochemistry , Biomarkers, Tumor , Cohort Studies , In Situ Hybridization, Fluorescence , Genetic Heterogeneity , Neoplasm Grading
7.
Biol. Res ; 52: 26, 2019. graf
Article in English | LILACS | ID: biblio-1011428

ABSTRACT

BACKGROUND: Acute myeloid leukemia (AML) is an aggressive and mostly incurable hematological malignancy with frequent relapses after an initial response to standard chemotherapy. Therefore, novel therapies are urgently required to improve AML clinical outcomes. 4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative designed and synthesized by our team, has been proven to show biological anti-tumor characteristics in our previous studies. However, its potential effect on leukemia remains unknown. The present research aims to investigate the underlying mechanism of treating leukemia with ATPR in vitro. METHODS: In this study, the AML cell lines NB4 and THP-1 were treated with ATPR. Cell proliferation was analyzed by the CCK-8 assay. Flow cytometry was used to measure the cell cycle distribution and cell differentiation. The expression levels of cell cycle and differentiation-related proteins were detected by western blotting and immunofluorescence staining. The NBT reduction assay was used to detect cell differentiation. RESULTS: ATPR inhibited cell proliferation, induced cell differentiation and arrested the cell cycle at the G0/G1 phase. Moreover, ATPR treatment induced a time-dependent release of reactive oxygen species (ROS). Additionally, the PTEN/PI3K/Akt pathway was downregulated 24 h after ATPR treatment, which might account for the anti-AML effects of ATPR that result from the ROS-mediated regulation of the PTEN/PI3K/AKT signaling pathway. CONCLUSIONS: Our observations could help to develop new drugs targeting the ROS/PTEN/PI3K/Akt pathway for the treatment of AML.


Subject(s)
Humans , Retinoids/pharmacology , Reactive Oxygen Species/metabolism , Antineoplastic Agents/pharmacology , Fluoroimmunoassay , Leukemia, Myeloid, Acute , Signal Transduction , Down-Regulation , Cell Differentiation/drug effects , Cell Survival/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , PTEN Phosphohydrolase/drug effects , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins c-akt/drug effects , Proto-Oncogene Proteins c-akt/metabolism
8.
Mem. Inst. Oswaldo Cruz ; 110(8): 996-1002, Dec. 2015. graf
Article in English | LILACS | ID: lil-769833

ABSTRACT

Chagas disease, which is caused by the intracellular protozoanTrypanosoma cruzi, is a serious health problem in Latin America. The heart is one of the major organs affected by this parasitic infection. The pathogenesis of tissue remodelling, particularly regarding cardiomyocyte behaviour after parasite infection, and the molecular mechanisms that occur immediately following parasite entry into host cells are not yet completely understood. Previous studies have reported that the establishment of parasitism is connected to the activation of the phosphatidylinositol-3 kinase (PI3K), which controls important steps in cellular metabolism by regulating the production of the second messenger phosphatidylinositol-3,4,5-trisphosphate. Particularly, the tumour suppressor PTEN is a negative regulator of PI3K signalling. However, mechanistic details of the modulatory activity of PTEN on Chagas disease have not been elucidated. To address this question, H9c2 cells were infected with T. cruzi Berenice 62 strain and the expression of a specific set of microRNAs (miRNAs) were investigated. Our cellular model demonstrated that miRNA-190b is correlated to the decrease of cellular viability rates by negatively modulating PTEN protein expression in T. cruzi-infected cells.


Subject(s)
Animals , Rats , Down-Regulation , MicroRNAs/physiology , Myocytes, Cardiac/parasitology , Protein Biosynthesis , PTEN Phosphohydrolase/metabolism , Trypanosoma cruzi/metabolism , Blotting, Western , Cell Line , Cell Survival , Formazans , Genes, Reporter , Myocytes, Cardiac/metabolism , Phosphorylation , PTEN Phosphohydrolase/genetics , Reverse Transcriptase Polymerase Chain Reaction , RNA, Messenger/metabolism , Tetrazolium Salts , Trypanosoma cruzi/classification
9.
Article in English | WPRIM | ID: wpr-71536

ABSTRACT

Several pathologic characteristics are associated with an adverse clinical outcome in papillary thyroid carcinoma (PTC), including the histological variant. This study aimed to investigate immunohistochemical expression and BRAF mutation status based on the histological variant and evaluated potential markers of aggressive behavior of PTC in Korean patients. In all, 407 PTC cases were classified to each histological variant, and the 94 representative cases were subjected to immunohistochemistry and BRAF mutation analysis. The classic type, follicular variant (FV) and tall cell variant (TCV) represented 76.9%, 14.2% and 6%, respectively. TCV showed a larger tumor size (P = 0.009), frequent extrathyroidal extension (P = 0.022) and cervical lymph node (LN) metastasis (P = 0.018). TCV and FV showed the reduced expression of galectin-3 (P = 0.003) and HBME1 (P = 0.114). Regardless of histology, PTEN loss and diffuse S100A4 expression were associated with LN metastasis (P = 0.007, P = 0.013). All TCVs harbored BRAF V600E mutation, and FV harbored less BRAF V600E mutation (P = 0.043). Immunohistochemical evaluation showed characteristic patterns in histological variants. PTEN and S100A4 expression are suggested as indicators of regional lymph node metastasis.


Subject(s)
Adult , Aged , Aged, 80 and over , Asian Continental Ancestry Group/genetics , Carcinoma, Papillary/genetics , DNA Mutational Analysis , Exons , Female , Galectin 3/metabolism , Humans , Immunohistochemistry , Lymphatic Metastasis , Male , Middle Aged , Mutation , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins B-raf/genetics , Republic of Korea , S100 Proteins/metabolism , Thyroid Neoplasms/genetics , Biomarkers, Tumor/metabolism , Young Adult
10.
Rev. méd. Chile ; 134(3): 271-278, mar. 2006. ilus, tab, graf
Article in Spanish | LILACS | ID: lil-426091

ABSTRACT

Background: Endometrioid carcinoma and clear cell carcinoma of the ovary are associated to endometriosis. Somatic mutations of PTEN (10q23.3) are present in endometrial endometrioid carcinoma. Therefore, these mutations could be also present in ovarian tumors. Molecular studies show that solitary endometriotic cysts are monoclonal, have aneuploid DNA, have a loss of 9p,11q and 22q heterozygosity (LOH) and a higher cellular proliferation index of the epithelial component. Aim: To determine the cellular proliferation index using Ki 67, the immunohistochemical expression of PTEN and LOH in patients with ovarian endometriosis without atypia (EN), ovarian endometriosis with atypia (EA) and endometriosis with adjacent ovarian carcinoma (ET). Material and methods: Paraffin embedded samples of 37 endometrioid and clear cell carcinomas of the ovary (CC/CE), 15 solitary ovarian EN and 15 ovarian EA, were studied. Expression of Ki 67 and PTEN was measured by immunohistochemistry. LOH of 10q23.3 locus was measured by polymerase chain reaction. Results: Ki 67 was 5.5 and 2.3% in EA and EN, respectively (p <0.005). There was a histological correlation between EA and a higher cellular proliferation index. PTEN was negative in 5 of 15 EN, 9 of 15 EA and 30 of 37 CE/CC. There was a correlation between LOH and loss of PTEN protein in EN, EA and ET (60%). Conclusions: Negative expression on PTEN in EN; EA; ET and CE/CC is a manifestation of the inactivation of this gene. The mechanisms that cause this inactivation, must be elucidated.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Middle Aged , Adenocarcinoma, Clear Cell/genetics , Carcinoma, Endometrioid/genetics , Endometriosis/genetics , Ovarian Neoplasms/genetics , PTEN Phosphohydrolase/genetics , Adenocarcinoma, Clear Cell/pathology , Carcinoma, Endometrioid/pathology , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Disease Progression , Endometriosis/pathology , Genetic Markers , Immunohistochemistry , /genetics , /metabolism , Loss of Heterozygosity/genetics , Ovarian Neoplasms/pathology , PTEN Phosphohydrolase/metabolism
11.
Article in Korean | WPRIM | ID: wpr-70848

ABSTRACT

BACKGROUND/AIMS: Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a recently clarified tumor suppressor gene located in 10q23.3. Alterations of this gene are associated with tumor progression and unfavorable outcome in various human cancers. Recently, PTEN has a possible role in angiogenesis by modulating angiogenic factor including vascular endothelial growth factor (VEGF). The aim of this study was to investigate the roles of PTEN and VEGF status for angiogenesis in human gastric cancer. METHODS: We conducted an immunohistochemical investigation of PTEN and VEGF expression in 90 cases of paraffin section obtained from gastric cancer patients undergone surgical treatment. RESULTS: Negative expression of PTEN and positive expression of VEGF in gastric cancer tissues, were demonstrated in 40.0% and 77.8% of cases, respectively. However, no significant correlation was found between PTEN, VEGF expression and various clinicopathological parameters. PTEN expression did not correlate significantly with VEGF expression (p=0.301). High microvessel density (MVD) was significantly associated with lymph node metastasis and poor survival (p=0.014, 0.011, respectively). The mean MVD value of PTEN negative tumors was 90.4+/-43.0 and significantly higher than that of PTEN positive tumors (p=0.028). The mean MVD value of VEGF positive tumors was 86.4+/-36.7 and significantly higher than that of VEGF negative tumors (p=0.002). The mean MVD value of PTEN negative and VEGF positive tumors was 98.0+/-42.2, and significantly higher than those of the others. CONCLUSIONS: These results suggest that loss of PTEN expression may play a critical role in tumor progression and metastasis by stimulating tumor angiogenesis in human gastric cancer.


Subject(s)
Adult , Aged , Carcinoma/blood supply , Disease Progression , Female , Humans , Immunohistochemistry , Male , Microcirculation/pathology , Middle Aged , Neovascularization, Pathologic/metabolism , PTEN Phosphohydrolase/metabolism , Stomach Neoplasms/blood supply , Survival Rate , Vascular Endothelial Growth Factor A/metabolism
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