Rspo2-LGR4 exacerbates hepatocellular carcinoma progression via activation of Wnt/b-catenin signaling pathway / Rspo2-LGR4 agrava la progresión del carcinoma hepatocelular al activar la vía de señalización Wnt/beta-catenina

Background: The leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4) plays an important role in stem cell differentiation, organ development and cancer. Whether LGR4 affects the progression of hepatocellular carcinoma (HCC) remains unknown. This study aimed to reveal the role of LGR4 in HCC. Methods: Clinical samples of HCC were collected to assess the expression of LGR4 and its correlation with patients’ clinical characteristics. The expression level of LGR4 in HCC cells was altered by pharmacological and genetic methods, and the role of LGR4 in HCC progression was analyzed by in vivo and in vitro assays. HCC was induced by diethylnitrosamine (DEN) and carbon tetrachloride (CCl4) in wild-type and LGR4 deficient mice, the effect of LGR4 on HCC was examined by histopathological evaluation and biochemical assays. Results: LGR4 expression was up-regulated in HCC samples, and its expression level was positively correlated with tumor size, microvascular invasion (MVI), TNM stage and pathological differentiation grade of HCC patients. In the mouse HCC model induced by DEN+CCl4, knockdown of LGR4 effectively inhibited the progression of HCC. Silencing of LGR4 inhibited the proliferation, migration, invasion, stem cell-like properties and Warburg effect of HCC cells. These phenotypes were promoted by R-spondin2 (Rspo2), an endogenous ligand for LGR4. Rspo2 markedly increased the nuclear translocation of β-catenin, whereas IWR-1, an inhibitor of Wnt/β-catenin signaling, reversed its effect. Deficiency of LGR4 significantly reduced the nuclear translocation of β-catenin and the expression of its downstream target genes cyclinD1 and c-Myc. Conclusions: LGR4 promotes HCC progression via Wnt/β-catenin signaling pathway. (AU)

Antecedentes: El receptor de acoplamiento de proteínas G de secuencia repetida 4 (LGR4), rico en leucina, juega un papel importante en la diferenciación de células madre, el desarrollo de órganos y el cáncer. Se desconoce si LGR4 afecta la progresión del carcinoma hepatocelular (HCC). El objetivo de este estudio es revelar el papel de LGR4 en el HCC. Métodos: Se recolectaron muestras clínicas de HCC para evaluar la expresión de LGR4 y su correlación con los resultados clínicos de HCC. Alterar los niveles de expresión de LGR4 en las células de HCC mediante métodos farmacológicos y genéticos y analizar el papel de LGR4 en la progresión del cáncer de hígado mediante mediciones in vivo e in vitro. El HCC fue inducido en ratones de tipo salvaje y con defectos de LGR4 con Nitrosamina de dietilo (DEN) y cloruro de carbono (CCl4), y los efectos de LGR4 sobre el HCC fueron detectados por evaluación histopatológica y determinación bioquímica. Resultados: La expresión de LGR4 está regulada en HCC, y su nivel de expresión está positivamente relacionado con el tamaño tumoral, la infiltración microvascular (MVI), la etapa de TNM y el grado de diferenciación patológica en pacientes con HCC. En el modelo de HCC de ratón inducido por DEN+CCl4, golpear bajo LGR4 inhibió efectivamente la progresión del HCC. El silencio de LGR4 inhibe la proliferación, migración, invasión, propiedades similares a las células madre y el efecto Warburg de las células HCC. Estos fenotipos son promovidos por el ligando endógeno roof slab-specific sponge 2 (Rspo2)de LGR4. El Rspo2 aumentó significativamente la translocación nuclear de la proteína beta-catenina, mientras que el inhibidor de la señalización Wnt/beta-cateninaIWR-1 revirtió su acción... (AU)

Rspo2-LGR4 exacerbates hepatocellular carcinoma progression via activation of Wnt/ß-catenin signaling pathway.

BACKGROUND: The leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4) plays an important role in stem cell differentiation, organ development and cancer. Whether LGR4 affects the progression of hepatocellular carcinoma (HCC) remains unknown. This study aimed to reveal the role of LGR4 in HCC. METHODS: Clinical samples of HCC were collected to assess the expression of LGR4 and its correlation with patients' clinical characteristics. The expression level of LGR4 in HCC cells was altered by pharmacological and genetic methods, and the role of LGR4 in HCC progression was analyzed by in vivo and in vitro assays. HCC was induced by diethylnitrosamine (DEN) and carbon tetrachloride (CCl4) in wild-type and LGR4 deficient mice, the effect of LGR4 on HCC was examined by histopathological evaluation and biochemical assays. RESULTS: LGR4 expression was up-regulated in HCC samples, and its expression level was positively correlated with tumor size, microvascular invasion (MVI), TNM stage and pathological differentiation grade of HCC patients. In the mouse HCC model induced by DEN+CCl4, knockdown of LGR4 effectively inhibited the progression of HCC. Silencing of LGR4 inhibited the proliferation, migration, invasion, stem cell-like properties and Warburg effect of HCC cells. These phenotypes were promoted by R-spondin2 (Rspo2), an endogenous ligand for LGR4. Rspo2 markedly increased the nuclear translocation of ß-catenin, whereas IWR-1, an inhibitor of Wnt/ß-catenin signaling, reversed its effect. Deficiency of LGR4 significantly reduced the nuclear translocation of ß-catenin and the expression of its downstream target genes cyclinD1 and c-Myc. CONCLUSIONS: LGR4 promotes HCC progression via Wnt/ß-catenin signaling pathway.