RESUMO
Hepatitis B virus [HBV], the best-described hepadnavirus, is distributed all around the world and may lead to chronic and acute liver disease, cirrhosis, and hepatocellular carcinoma. Despite the advancement in treatment against HBV, an errorprone reverse transcriptase, which is required for HBV replication as well as host immune pressure, leads to constant evolution and emergence of genotypes, subgenotypes and mutant viruses; so, HBV will remain as a major healthcare problem around the world. This review article mainly focuses on the HBV mutations which correlated to occult HBV infection, immune escape, vaccine failure and eventually liver cirrhosis and HCC. The current study indicated that preS/S region mutations are related to vaccine failure, immune escape, occult HBV infection and the occurrence of HCC. Whereas P region Mutations may lead to drug resistance to NA antivirals. PreC/C region mutations are associated with HBeAg negativity, immune escape, and persistent hepatitis. Moreover, X region Mutations play an important role in HCC development.
Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Vacinas , Carcinoma Hepatocelular/genética , Genótipo , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , MutaçãoRESUMO
Integrins are cell adhesion receptors, which are typically transmembrane glycoproteins that connect to the extracellular matrix (ECM). The function of integrins regulated by biochemical events within the cells. Understanding the mechanisms of cell growth by integrins is important in elucidating their effects on tumor progression. One of the major events in integrin signaling is integrin binding to extracellular ligands. Another event is distant signaling that gathers chemical signals from outside of the cell and transmit the signals upon cell adhesion to the inside of the cell. In normal breast tissue, integrins function as checkpoints to monitor effects on cell proliferation, while in cancer tissue these functions altered. The combination of tumor microenvironment and its associated components determines the cell fate. Hypoxia can increase the expression of several integrins. The exosomal integrins promote the growth of metastatic cells. Expression of certain integrins is associated with increased metastasis and decreased prognosis in cancers. In addition, integrin-binding proteins promote invasion and metastasis in breast cancer. Targeting specific integrins and integrin-binding proteins may provide new therapeutic approaches for breast cancer therapies. This review will examine the current knowledge of integrins' role in breast cancer.
