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Perforin-1 (PRF), a cytotoxic lymphocyte pore-forming protein, plays an important role in the action of cytotoxic T cells and natural killer cells in that it causes the lysis of abnormal body cells and the elimination of virus-infected cells and tumors. Upon degranulation, PRF inserts itself into the target cell's plasma membrane, forming a pore. The subsequent translocation of pro-apoptotic granzymes (including granzyme B, A, M et al.) into the cytoplasm provides the proteases with access to numerous protein substrates that promote apoptosis after cleavage. These proteases are believed to be the main executioners of target cell apoptosis. Although the PRF and granzyme components are both critical to this process and in some way involved in inducing cell death in target cells, the inhibition of tumor growth could still be efficient in granzymedeficient mice. It is unclear whether PRF alone can suppress tumors. In this study, we discovered that forced ectopic expression of PRF alone, in the absence of granzymes, could mediate cell death in cancer cells. Notably, transient expression of both full-length and truncated active-form PRF in human Hep G2, SK-BR-3, and HeLa cells was found to induce apparent cell growth inhibition and cell death, as evidenced by chromosome condensation and DNA fragmentation, increased caspase-3 activity, and the release of apoptosis inducing factor (AIF) and cytochrome c from the mitochondria. This PRFinduced cell death could be abrogated by pan-caspase inhibitor (Z-VAD) and mitochondria protector (TAT-BH4). The implication of these results is that ectopically expressed PRF has apoptosis-inducing abilities, and PRF alone is sufficient to induce apoptotic cell death in cells with ectopic expression. Taking this into consideration, our results suggest the possibility of using PRF as a pro-apoptotic gene for tumor therapeutics. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer(CRC) is a highly heterogeneous malignant tumor that significantly impacts clinical diagnosis and treatment. Single-cell RNA sequencing is an innovative method for exploring tumor heterogeneity and understanding its role at cellular and genetic levels. Method: The colorectal cancer Single-cell RNA sequencing data were analysed on the immune. RNA-seq data in bulk form was utilized to assess the major genes of the immune cell subsets linked to CRC. We conducted an analysis of the abundance of immune cells in the microenvironment of CRC, and also performed weighted gene co-expression network analysis. Gene set enrichment analysis helped perform two analytical procedures of subtype groups. Furthermore, Least absolute shrinkage and selection operator regression was employed to analyse and screen for a gene signature. Finally, quantitative PCR was performed to detect the expression levels of signature genes in CRC. Results: The Single-cell RNA sequencing (GSE146771) dataset was integrated to obtain 9 cell clusters. The Single-sample gene set enrichment analysis showed that the related gene expression of T-cell subsets of different functional statuses could vary greatly between patients with GSE146771. Immune cell analysis of TCGA-CRC indicated an improved overall survival rate for patients with elevated Th2 cell abundance. Five-gene signature (Risk Score = -0.205 × CDC25C - 0.231 × GSTCD - 0.010 × KPNA2 - 0.002 × KIF15 - 0.171 × ORC1) was developed by weighted correlation network analysis, and lasso Cox regression. Then, the risk prediction efficacy of the signature was validated in four GSE datasets. Furthermore, the expression of five genes was reduced in CRC tissue by quantitative PCR. Conclusion: Five-gene signature based on CRC heterogeneity was developed as a prognosis predictor, which can serve as a potential treatment target. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of ethanol on the expression of caveolin-1 (CAV-1) in HepG2 hepatocarcinoma cells. Ethanol-treated HepG2 cells were investigated using the in vitro model to determine whether ethanol can influence the expression of CAV-1. Cell viability was measured using the colorimetric 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Expression of CAV-1 was detected using western blot analysis. Quantitative PCR (qPCR) was used to determine CAV-1 mRNA levels. The distribution of CAV-1 in HepG2 cells was analyzed using immunofluorescence. The MTT assay results revealed that cell viability was not altered at ethanol concentrations of <1.0%, while ethanol concentrations >1.0% caused cell shedding, but not cell fragmentation. Western blot analysis showed significant differences in the levels of CAV-1 expression between the control group and the 1.0% ethanol-treated group at 6, 12 and 24 h (all P<0.05). qPCR showed significant differences in the expression levels of caveolin-1 mRNA between the control group and the 1.0% ethanol-treated group at 6 h, 12 h and 24 h (all P<0.05). Immunofluorescence demonstrated that CAV-1 was distributed discontinuously at the boundaries of HepG2 cells. The results indicate that ethanol may increase the expression of CAV-1 in HepG2 cells. [ABSTRACT FROM AUTHOR]