Molecular and immunohistochemical study of the inactivation of the p16 gene in primary hepatocellular carcinoma

Obejctive To determine whether p16 gene is involved in the genesis of primary hepatocellular carcinoma (HCC) Methods Twenty five HCC tumor samples with corresponding non tumor liver tissue specimens were examined for p16 gene alterations The identification of deletion of exon 1 and exon 2 in p16 gene was performed using comparative multiplex polymerase chain reaction (PCR) analysis The point mutation of exon 2 in p16 gene was investigated by single strand conformational polymorphism (SSCP) analysis, and the status of p16 gene methylation was screened using a PCR based methylation analysis 35 parafin embedded specimens of HCC with corresponding non tumor liver tissues, including the 25 cases described above for screening p16 gene alterations, were investigated for p16 protein expression using immunohistochemical analysis Results Among 25 cases, 2 homozygous deletions and 1 hemizygous deletion were found in HCC samples No point mutation was identified in the remaining 22 tumor samples without p16 gene deletions Hypermethylation was detected in 24% (6/25) of tumor samples However, the corresponding non tumor liver tissue specimens were always unmethylated at the p16 locus Loss of p16 protein expression occurred in 16 of 35 (45 7%) tumor samples, and all the non tumor liver tissue specimens showed positive p16 staining For the 25 cases examined for p16 gene alterations, the loss of p16 protein expression was observed in all tumors with p16 gene alterations and also in 3 tumors without p16 gene alterations Conclusion Inactivation of the p16 gene may play an important role in the genesis of primary hepatocellular carcinoma

CRISPR/Cas9 system and its applications in nervous system diseases

The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system is an acquired immune system of many bacteria and archaea,comprising CRISPR loci,Cas genes,and its associated proteins.This system can recognize exogenous DNA and utilize the Cas9 protein's nuclease activity to break DNA double-strand and to achieve base insertion or deletion by subsequent DNA repair.In recent years,multiple laboratory and clinical studies have revealed the therapeutic role of the CRISPR/Cas9 system in neurological diseases.This article reviews the CRISPR/Cas9-mediated gene editing technology and its potential for clinical application against neurological diseases.

Role of pyroptosis in inflammation and cancer

Pyroptosis is a form of programmed cell death mediated by gasdermin and is a product of continuous cell expansion until the cytomembrane ruptures,resulting in the release of cellular contents that can activate strong inflammatory and immune responses.Pyroptosis,an innate immune response,can be triggered by the activation of inflammasomes by various influencing factors.Activation of these inflammasomes can induce the maturation of caspase-1 or caspase-4/5/11,both of which cleave gasdermin D to release its N-terminal domain,which can bind membrane lipids and perforate the cell membrane.Here,we review the latest advancements in research on the mechanisms of pyroptosis,newly discovered influencing factors,antitumoral properties,and applications in various diseases.Moreover,this review also provides updates on potential targeted therapies for inflammation and cancers,methods for clinical prevention,and finally challenges and future directions in the field.