GABRIEL ARANTES GALVAO DIAS DOS SANTOS

(Fonte: Lattes)
Índice h a partir de 2011
6
Projetos de Pesquisa
Unidades Organizacionais
LIM/55 - Laboratório de Urologia, Hospital das Clínicas, Faculdade de Medicina

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Agora exibindo 1 - 10 de 23
  • article 7 Citação(ões) na Scopus
    Can we use Ki67 expression to predict prostate cancer aggressiveness?
    (2022) MAIA, RONALDO; SANTOS, GABRIEL ARANTES DOS; REIS, SABRINA; VIANA, NAYARA I; PIMENTA, RUAN; GUIMARÃES, VANESSA R; RECUERO, SAULO; ROMÃO, POLIANA; LEITE, KATIA RAMOS MOREIRA; SROUGI, MIGUEL; PASSEROTTI, CARLO CARMARGO
    ABSTRACT Introduction: specialists have an urge for biomarkers that can discriminate indolent prostate cancer from aggressive tumors. Ki67 is a proliferation marker, and its expression is associated with the aggressiveness of several cancers. Objective: analyze the expression of Ki67 in prostate cancer samples correlating with the aggressiveness of the disease. Methods: Ki67 mRNA levels were determined utilizing data from a TCGA cohort (Tumor(n)=492 and control(n)=52). The protein expression was determined on 94 biopsies from patients by immunohistochemical assay. Results: in mRNA, the Ki67 upregulation is associated with cancer tissue (p<0.0001) and worst disease-free survival (p=0.035). The protein upregulation is associated with increase of the ISUP score (p<0.0001), cancer stage (p=0.05), biochemical recurrence (p=0.0006) and metastasis (p<0.0001). We also show a positive correlation between Ki67 expression and ISUP score (r=0.5112, p<0.0001) and disease risk stratification (r=0.3388, p=0.0009). Ki67 expression is a factor independently associated with biochemical recurrence (p=0.002) and metastasis (p<0.0001). Finally, the patients with high Ki67expression shows better survival regarding biochemical recurrence (p=0.008) and metastasis (p=0.056). Patients with high Ki67 expression are 2.62 times more likely to develop biochemical recurrence (p=0.036). Conclusion: Ki67 upregulation is associated with prostate cancer aggressiveness.
  • article 4 Citação(ões) na Scopus
    Hypothesis: The triad androgen receptor, zinc finger proteins and telomeres modulates the global gene expression pattern during prostate cancer progression
    (2021) SANTOS, Gabriel Arantes dos; VIANA, Nayara Izabel; PIMENTA, Ruan; REIS, Sabrina T.; LEITE, Katia Ramos Moreira; SROUGI, Miguel
    Currently, the biggest challenge for prostate cancer (PCa) is to understand the mechanism by which the disease acquires the castration-resistant phenotype and progresses to a fatal disease. PCa has a high genetic heterogeneity, and cannot be separated into well-defined molecular subtypes. Despite this, there is consensus about the role of the androgen receptor (AR) in all stages of the disease, including the transition to the castration-resistant phenotype. Since AR is a transcription factor, we investigated the possibility of PCa presenting a pattern of global gene expression during disease progression. By analyzing the TCGA and CCLE datasets, we were able to find a pattern of waves of genes being expressed during each stage of disease progression. This phenomenon suggests the existence of a mechanism that globally regulates gene expression, being AR, telomeres, and zinc finger proteins (ZNF), three important players. The AR modulates the telomere biology, and its transcription is regulated by ZNF. Recently, a study suggested that the telomere length might influence the expression of ZNF. Thus, we hypothesized that changes in the triad AR, telomeres, and ZNF control gene expression during the progression of PCa.
  • article 1 Citação(ões) na Scopus
    Upregulation of shelterin and CST genes and longer telomeres are associated with unfavorable prognostic characteristics in prostate cancer
    (2024) SANTOS, Gabriel Arantes dos; I, Nayara Viana; PIMENTA, Ruan; CAMARGO, Juliana Alves de; GUIMARAES, Vanessa R.; ROMA, Poliana; CANDIDO, Patricia; SANTOS, Vinicius Genuino dos; REIS, Sabrina; LEITE, Katia Ramos Moreira; SROUGI, Miguel
    Introduction: Search for new clinical biomarkers targets in prostate cancer (PC) is urgent. Telomeres might be one of these targets. Telomeres are the extremities of linear chromosomes, essential for genome stability and control of cell divisions. Telomere homeostasis relies on the proper functioning of shelterin and CST complexes. Telomeric dysfunction and abnormal expression of its components are reported in most cancers and are associated with PC. Despite this, there are only a few studies about the expression of the main telomere complexes and their relationship with PC progression. We aimed to evaluate the role of shelterin (POT1, TRF2, TPP1, TIN2, and RAP1) and CST (CTC1, STN1, and TEN1) genes and telomere length in the progression of PC. Methods: We evaluated genetic alterations of shelterin and CST by bioinformatics in samples of localized (n = 499) and metastatic castration-resistant PC (n = 444). We also analyzed the expression of the genes using TCGA (localized PC n = 497 and control n = 152) and experimental approaches, with surgical specimens (localized PC n = 81 and BPH n = 10) and metastatic cell lines (LNCaP, DU145, PC3 and PNT2 as control) by real-time PCR. Real-time PCR also determined the telomere length in the same experimental samples. All acquired data were associated with clinical parameters. Results: Genetic alterations are uncommon in PC, but POT1, TIN2, and TEN1 showed significantly more amplifications in the metastatic cancer. Except for CTC1 and TEN1, which are differentially expressed in localized PC samples, we did not detect an expression pattern relative to control and cell lines. Nevertheless, except for TEN1, the upregulation of all genes is associated with a worse prognosis in localized PC. We also found that increased telomere length is associated with disease aggressiveness in localized PC. Conclusion: The upregulation of shelterin and CST genes creates an environment that favors telomere elongation, giving selective advantages for localized PC cells to progress to more aggressive stages of the disease.
  • article 0 Citação(ões) na Scopus
    Evidence of a pan-tissue decline in stemness during human aging
    (2024) SANTOS, Gabriel Arantes dos; MAGDALENO, Gustavo Daniel Vega; MAGALHAES, Joao Pedro de
    Despite their biological importance, the role of stem cells in human aging remains to be elucidated. In this work, we applied a machine learning methodology to GTEx transcriptome data and assigned stemness scores to 17,382 healthy samples from 30 human tissues aged between 20 and 79 years. We found that (similar to)60% of the studied tissues exhibit a significant negative correlation between the subject's age and stemness score. The only significant exception was the uterus, where we observed an increased stemness with age. Moreover, we observed that stemness is positively correlated with cell proliferation and negatively correlated with cellular senescence. Finally, we also observed a trend that hematopoietic stem cells derived from older individuals might have higher stemness scores. In conclusion, we assigned stemness scores to human samples and show evidence of a pan-tissue loss of stemness during human aging, which adds weight to the idea that stem cell deterioration may contribute to human aging.
  • article 0 Citação(ões) na Scopus
    PSA density of the lesion: a mathematical formula that uses clinical and pathological data to predict biochemical recurrence in prostate cancer patients
    (2021) JUNQUEIRA, PEDRO HENRIQUE REZENDE; SANTOS, GABRIEL ARANTES DOS; XAVIER, MARCELO; ROMÃO, POLIANA; REIS, SABRINA; SROUGI, MIGUEL; NAHAS, WILLIAN CARLOS; PASSEROTTI, CARLO CARMARGO
    ABSTRACT A main challenge in the clinical management of prostate cancer is to identify which tumor is aggressive and needs invasive treatment. Thus, being able to predict which cancer will progress to biochemical recurrence is a great strategy to stratify prostate cancer patients. With that in mind, we created a mathematical formula that takes into account the patients clinical and pathological data resulting in a quantitative variable, called PSA density of the lesion, which has the potential to predict biochemical recurrence. To test if our variable is able to predict biochemical recurrence, we use a cohort of 219 prostate cancer patients, associating our new variable and classic parameters of prostate cancer with biochemical recurrence. Total PSA, lesion weight, volume and classic PSA density were positively associated with biochemical recurrence (p<0.05). ISUP score was also associated with biochemical recurrence in both biopsy and surgical specimen (p<0.001). The increase of PSA density of the lesion was significantly associated with the biochemical recurrence (p=0.03). Variables derived from the formula, PSA 15% and PSA 152, were also positive associated with the biochemical recurrence (p=0.01 and p=0.002 respectively). Logistic regression analysis shows that classic PSA density, PSA density of the lesion and total PSA, together, can explain up to 13% of cases of biochemical recurrence. PSA density of the lesion alone would have the ability to explain up to 7% of cases of biochemical recurrence. In conclusion, this new mathematical approach could be a useful tool to predict disease recurrence in prostate cancer.
  • article 4 Citação(ões) na Scopus
    Prognostic value of TERF1 expression in prostate cancer
    (2021) SANTOS, Gabriel Arantes dos; VIANA, Nayara Izabel; PIMENTA, Ruan; GUIMARAES, Vanessa Ribeiro; CAMARGO, Juliana Alves de; ROMAO, Poliana; REIS, Sabrina T.; LEITE, Katia Ramos Moreira; SROUGI, Miguel
    Background: Telomere dysfunction is one of the hallmarks of cancer and is crucial to prostate carcinogenesis. TERF1 is a gene essential to telomere maintenance, and its dysfunction has already been associates with several cancers. TERF1 is a target of miR-155, and this microRNA can inhibit its expression and promotes carcinogenesis in breast cancer. We aim to analyze TERF1, in gene and mRNA level, involvement in prostate cancer progression. Results: Alterations in TERF1 DNA were evaluated using datasets of primary tumor and castration-resistant tumors (CRPC) deposited in cBioportal. The expression of TERF1 mRNA levels was assessed utilizing TCGA datasets, clinical specimens, and metastatic prostate cancer cell lines (LNCaP, DU145, and PC3). Six percent of localized prostate cancer presents alterations in TERF1 (the majority of that was amplifications). In the CRPC cohort, 26% of samples had TERF1 amplification. Patients with TERF1 alterations had the worst overall survival only on localized cancer cohort (p = 0.0027). In the TCGA cohort, mRNA levels of TERF1 were downregulated in comparison with normal tissue (p = 0.0013) and upregulated in tumors that invade lymph nodes (p = 0.0059). The upregulation of TERF1 is also associated with worst overall survival (p = 0.0028) and disease-free survival (p = 0.0023). There is a positive correlation between TERF1 and androgen receptor expression in cancer tissue (r = 0.53, p < 0.00001) but not on normal tissue (r = - 0.16, p = 0.12). In the clinical specimens, there is no detectable expression of TERF1 and upregulation of miR-155 (p = 0.0348). In cell lines, TERF1 expression was higher in LNCaP and was progressively lower in DU145 and PC3 (p = 0.0327) with no differences in miR-155 expression. Conclusion: Amplification/upregulation of TERF1 was associated with the worst prognostic in localized prostate cancer. Our results corroborate that miR-155 regulates TERF1 expression in prostate cancer. TERF1 has the potential to become a biomarker in prostate cancer.
  • article 1 Citação(ões) na Scopus
    The influence of interstitial cells of Cajal density in the outcomes of pyeloplasty in adults: A prospective analysis
    (2023) SROUGI, Victor; BANDEIRA, Rodolfo Anisio Santana de Torres; REIS, Sabrina Thalita; SANTOS, Gabriel Arantes dos; ANDRADE, Hiury da Silva; LEITE, Katia Ramos Moreira; HAMILTON-CHO, David; MITRE, Anuar Ibrahim; ARAP, Marco Antonio; SROUGI, Miguel; DUARTE, Ricardo Jordao
    Purpose: To evaluate if the density of interstitial cells of Cajal (ICC) in the ureteropelvic junction (UPJ) influences the outcomes of pyeloplasty in adults. Methods: Twenty-three patients with the diagnosis of ureteropelvic junction obstruction (UPJO) that underwent laparoscopic dismembered pyeloplasty were included. ICC density was measured using immunohistochemistry reaction for c-KIT expression in the resected UPJ segment. Pyeloplasty outcome was evaluated by patient self-report pain, urinary outflow using DTPA renogram and hydronephrosis assessment using ultrasound (US) at 12 months of follow-up. A logistic regression analysis was performed to assess the association of pyeloplasty outcomes and ICC density. Results: Low, moderate, and high ICC density were present in 17.4%, 30.4%, and 52.2% of the patients, respectively. Complete pain resolution was observed in 100%, 85.7%, and 75% of patients with low, moderate and high ICC density, respectively (p = 0.791). DTPA renogram improved in 75%, 85.7%, and 91.7% of patients with low, moderate and high ICC density, respectively (p = 0.739). Hydronephrosis improved in 25%, 85.7%, and 91.7% of patients with low, moderate and high ICC density, respectively (p = 0.032). Conclusions: Patients with high ICC density have a significant amelioration of hydronephrosis after pyeloplasty. However, ICC density is not associated with functional outcomes.
  • article 1 Citação(ões) na Scopus
    Telomere Attrition and p53 Response 1 (TAPR1): a new player in cancer biology?
    (2021) SANTOS, Gabriel Arantes dos; REIS, Sabrina T.; LEITE, Katia Ramos Moreira; SROUGI, Miguel
  • article 14 Citação(ões) na Scopus
    Shorter leukocyte telomere length is associated with severity of COVID-19 infection.
    (2021) SANTOS, Gabriel Arantes dos; PIMENTA, Ruan; I, Nayara Viana; GUIMARAES, Vanessa R.; ROMAO, Poliana; CANDIDO, Patricia; CAMARGO, Juliana A. de; HATANAKA, Dina M.; QUEIROZ, Paula G. S.; TERUYA, Alexandre; LEITE, Katia R. M.; SROUGI, Victor; SROUGI, Miguel; REIS, Sabrina T.
    The infection by COVID-19 is a serious global public health problem. An efficient way to improve this disease's clinical management would be to characterize patients at higher risk of progressing to critically severe infection using prognostic biomarkers. The telomere length could be used for this purpose. Telomeres are responsible for controlling the number of maximum cell divisions. The telomere length is a biomarker of aging and several diseases. We aimed to compare leukocyte telomere length (LTL) between patients without COVID-19 and patients with different clinical severity of the infection. Were included 53 patients who underwent SARS-CoV-2 PCR divided in four groups. The first group was composed by patients with a negative diagnosis for COVID-19 (n = 12). The other three groups consisted of patients with a confirmed diagnosis of COVID-19 divided according to the severity of the disease: mild (n = 15), moderate (n = 17) and severe (n = 9). The LTL was determined by QPCR. The severe group had the shortest LTL, followed by the moderate group. The negative and mild groups showed no differences. There is an increase of patients with hypertension (p = 0.0099) and diabetes (p = 0.0067) in moderate and severe groups. Severe group was composed by older patients in comparison with the other three groups (p = 0.0083). Regarding sex, there was no significant difference between groups (p = 0.6279). In an ordinal regression model, only LTL and diabetes were significantly associated with disease severity. Shorter telomere length was significantly associated with the severity of COVID-19 infection, which can be useful as a biomarker or to better understand the SARS-CoV-2 pathophysiology.
  • article 3 Citação(ões) na Scopus
    Transcriptomic analysis reveals a tissue-specific loss of identity during ageing and cancer
    (2023) SANTOS, Gabriel Arantes dos; CHATSIRISUPACHAI, Kasit; AVELAR, Roberto A.; MAGALHAES, Joao Pedro de
    IntroductionUnderstanding changes in cell identity in cancer and ageing is of great importance. In this work, we analyzed how gene expression changes in human tissues are associated with tissue specificity during cancer and ageing using transcriptome data from TCGA and GTEx.ResultsWe found significant downregulation of tissue-specific genes during ageing in 40% of the tissues analyzed, which suggests loss of tissue identity with age. For most cancer types, we have noted a consistent pattern of downregulation in genes that are specific to the tissue from which the tumor originated. Moreover, we observed in cancer an activation of genes not usually expressed in the tissue of origin as well as an upregulation of genes specific to other tissues. These patterns in cancer were associated with patient survival. The age of the patient, however, did not influence these patterns.ConclusionWe identified loss of cellular identity in 40% of the tissues analysed during human ageing, and a clear pattern in cancer, where during tumorigenesis cells express genes specific to other organs while suppressing the expression of genes from their original tissue. The loss of cellular identity observed in cancer is associated with prognosis and is not influenced by age, suggesting that it is a crucial stage in carcinogenesis.