PRKAB2 as a prognostic biomarker and Rottlerin as a potential chemotherapeutic for pediatric adrenocortical tumor

Author(s)

Alcides Euzebio Tavares Xavier

• Document type: Master's Dissertation
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina de Ribeirão Preto (PCARP/BC)
• Defense date: 2023-05-30

Examining board members

Carlos Alberto Scrideli; Lucila Leico Kagohara Elias; Andréia Machado Leopoldino

• Advisor: Carlos Alberto Scrideli

Abstract

Pediatric adrenocortical tumor (ACT) is a rare neoplasm with high heterogeneity. Unlike the adult CAT, the anatomopathological parameters are considered inaccurate in predicting the prognosis of patients, which causes difficulties in the evolution of the disease, treatment and biology of CATs. AMP-activated protein kinases (AMPK), which have the PRKAB2 gene as the producer of one of the subunits of its complex, exert crucial activities for the maintenance of embryonic development and are strongly associated with the main characteristics of cancer. However, little is known about its role in TAC. This study evaluated the association between the PRKAB2 gene and clinical and biological characteristics in 63 patients with pediatric adrenocortical tumors, as well as in vitro studies on human TAC cell lines. Gene expression was determined by real-time PCR (RT-qPCR), and in silico evaluation of public datasets of pediatric cases of CAT. Association analysis between PRKAB2 and clinical characteristics was performed using Mann-Whitney tests, Kaplan-Meier curves, log-rank test and multivariate analysis using the Cox method. An analysis using our cohort expression from public datasets (GSE76019) revealed the association between lower PRKAB2 levels with cases of relapse, deaths and metastasis. In addition, low expression of PRKAB2 was significantly associated with lower event-free and overall survival, in addition to demonstrating its capacity as an independent marker of worse prognosis when analyzed in conjunction with factors associated with patient outcomes. Our in vitro tests demonstrated that the agent Rottlerin, a drug with the potential to activate AMPK, increased PRKAB2 protein and mRNA levels. Furthermore, Rottlerin modulated the AMPK/mTOR, Wnt/β-catenin, SKP2, shh, MAPK, TNF pathways. At a functional level, treatment with this agent showed cell waiting, clonogenic capacity and cell migration in the NCI-H295R human TAC lineage. These results suggest that Rotterin may be a promising drug in the treatment of CAT. (AU)

• FAPESP's process: 21/10702-9 - Evaluation of the clinical and functional significance of the PRKAB2 gene in pediatric adrenocortical tumor
• Grantee: Alcides Euzebio Tavares Xavier
• Support Opportunities: Scholarships in Brazil - Master