Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological ...Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.展开更多
AIM: To evaluate the association between genetic polymorphisms of the gene encoding AMP-activated protein kinase (PRKAA1) and the risk of gastric cancer.
Radiotherapy is a part of the front-line treatment regime for many cancers. The mechanisms of radiation-induced effects in cancers mainly involves double-strand breaks (DBS) which plays very important role in maintain...Radiotherapy is a part of the front-line treatment regime for many cancers. The mechanisms of radiation-induced effects in cancers mainly involves double-strand breaks (DBS) which plays very important role in maintaining the stability of gene. As DNA repair gene breast cancer 1 (BRCA1) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) can act to maintain genetic stability though two distinct and complementary mechanisms for DNA DSB repair-homologous recombination (HR) and non-homologous end joining (NHEJ). Therefor, BRCA1 and DNA-PKcs are closely associated with radiation sensitivity, which means that they may be used as a useful tool to predict radio sensitivity in human tumour cells.展开更多
Fibrolamellar hepatocellular carcinoma(FLC)is a rare but aggressive liver cancer of children that occurs predominantly in teenagers without a history of liver disease.Surgical resection remains the only therapeutic op...Fibrolamellar hepatocellular carcinoma(FLC)is a rare but aggressive liver cancer of children that occurs predominantly in teenagers without a history of liver disease.Surgical resection remains the only therapeutic option,and the recurrence rate is extremely high(>50%within 3 years).A newly discovered chromosomal deletion that occurs in the majority of FLCs generates a novel kinase fusion between DnaJ heat shock protein family member B1(DNAJB1)and protein kinase cAMP-activated catalytic subunit alpha(PRKACA)(DNAJB1-PRKACA).Despite its high penetrance and apparent specificity for FLC,the oncogenic role of this fusion event remains unclear.In this review article,we discuss the histology,presentation and diagnosis,current treatment,and roles of the DNAJB1-PRKACA as well as research models contributing to our understanding of this disease.展开更多
基金supported by grants from Fundacao para a Ciencia e Tecnologia(FCT)of the Portuguese Ministry of Science and Higher Education(PTDC/DTP-PIC/0460/2012)by FEDER through Eixo I do Programa Operacional Fatores de Competitividade(POFC)(FCOMP-01-0124-FEDER-028692)co-funded by QREN
文摘Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.
基金Supported by A grant from the National R&D Program for Cancer Control,Ministry of Health and Welfare,South Korea,No.1120330
文摘AIM: To evaluate the association between genetic polymorphisms of the gene encoding AMP-activated protein kinase (PRKAA1) and the risk of gastric cancer.
文摘Radiotherapy is a part of the front-line treatment regime for many cancers. The mechanisms of radiation-induced effects in cancers mainly involves double-strand breaks (DBS) which plays very important role in maintaining the stability of gene. As DNA repair gene breast cancer 1 (BRCA1) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) can act to maintain genetic stability though two distinct and complementary mechanisms for DNA DSB repair-homologous recombination (HR) and non-homologous end joining (NHEJ). Therefor, BRCA1 and DNA-PKcs are closely associated with radiation sensitivity, which means that they may be used as a useful tool to predict radio sensitivity in human tumour cells.
文摘Fibrolamellar hepatocellular carcinoma(FLC)is a rare but aggressive liver cancer of children that occurs predominantly in teenagers without a history of liver disease.Surgical resection remains the only therapeutic option,and the recurrence rate is extremely high(>50%within 3 years).A newly discovered chromosomal deletion that occurs in the majority of FLCs generates a novel kinase fusion between DnaJ heat shock protein family member B1(DNAJB1)and protein kinase cAMP-activated catalytic subunit alpha(PRKACA)(DNAJB1-PRKACA).Despite its high penetrance and apparent specificity for FLC,the oncogenic role of this fusion event remains unclear.In this review article,we discuss the histology,presentation and diagnosis,current treatment,and roles of the DNAJB1-PRKACA as well as research models contributing to our understanding of this disease.
