ABSTRACT
Objective To evaluate the effect of exosomes from different sources on the growth, metastasis and immune microenvironment of hepatocellular carcinoma ( HCC ) in a mouse model of orthotopic transplanted hepatoma so as to provide new insight into the clinical immunotherapy of hepatocellular carcinoma. Methods The serum-derived exosomes were obtained by ultracentrifugation from Hepa1-6 cells and 3-week orthotopically tumor-bearing HCC mice. The morphology and size of exosomes were identified by transmission electron microscopy. One-week tumor-bearing HCC C57BL/6 mice were randomly divided into 3 groups ( 3 mice for each group ) , and respectively treated with tail vein injection of 120 μl PBS(control group), 120 μl Hepa1-6 cell-derived exosomes (1μg/μl, TEXcel group), and serum-derived exosomes (1μg/μl) (TEXserum group). The treatments were conduced once a week for 3 consecutive weeks. The mice were sacrificed on the 4th day after the treatments, and the liver tissue and lung tissues were dissected. The volumes of the liver cancer tissues were measured. The expression of PD-L1 protein and CD3+and FoxP3+T lymphocytes infiltration in the liver cancer tissues were respectively detected by Western Blot and immunohistochemical staining. The lung metastasis of the liver cancer was detected by hematoxylin-eosin staining. Results The diameters of the Hepa1-6 cell- and serum-derived exosomes both were about 100 nm, and were uniform vesicles with complete membrane structure. Compared with the control group, Hepa1-6 cell-derived exosomes had a certain inhibitory effect on the growth and lung metastasis of HCC, while there was no significant difference for the TEXserum group. Western Blot results showed that compared with the control group, PD-L1 protein expression was significantly up-regulated in both TEXcel group and TEXserum group. Immunohistochemical staining showed that compared with the control group, the infiltration number of Foxp3+-labeled regulatory T cells (Treg) had no significant changes in TEXcel group and the TEXserum group, and the differences were no statistically significant (all P>0.05). However, the infiltration number of CD3+-labeled T lymphocytes was significantly reduced in the two groups, and the differences were statistically significant (all P<0.05). Conclusion The Hepa1-6 cell-derived exosomes have a certain inhibitory effect on the growth and lung metastasis of HCC, and have no obvious regulation effects on the immune microenvironment of HCC. The serum-derived exosomes from orthotopically tumor-bearing HCC mice can promote the growth and lung metastasis of HCC and immunosuppress the microenvironment. The Hepa1-6 cell-derived exosomes are expected to be used for immunotherapy studies of liver cancer.
ABSTRACT
Objective To screen cardiac-specific short-acting peptides on live myocardial slices using phage display technology,so as to improve the targeted delivery efficiency of drugs in myocardium and provide effective candidates for the targeted therapy of Duchenne muscular dystrophy (DMD) and other cardiomyopathies.Methods Myocardial tissue slices were prepared and cultured in vitro.The protein activities of the tissues were examined by immunohistochemistry.The in vitro cultured myocardial tissue slices were co-incubated with phage library (1×1012 pfu),and the phages that bound to the myocardium were recovered and amplified.The cardiac-specific targeting phages were identified by five rounds of in vitro phage biopanning.The candidate phage-related insertion sequence was sequenced,and the in vivo tissue distribution of the highly enriched phages was verified.Results A platform for in vitro culturing of live myocardial slices was established.Myocardial slices with good biological activity were obtained.After 48 hours of culturing,the normal expression and localization of Dystrophin protein were detected.Using phage library,candidate phages were screened after five rounds of phage biopanning.The results of the sequencing analyses and in vivo tissue distribution verification indicated that the selected candidate phages showed significant enrichment in myocardium and skeletal muscle,and showed low levels in liver and kidney tissues.Conclusions The candidate phages showed higher binding efficiency in both myocardium and skeletal muscle,indicating that the candidate peptides had myocardial targeting property,and that can provide a new method for myocardial targeting therapy of DMD.
ABSTRACT
Objective To investigate the role of non-small cell lung cancer metastasis-related Trim72 gene in hepatocellular carcinoma (HCC) using clustered regularly interspaced short palindromic repeats (CRISPR) Cas9 system.Methods Hepa1-6 (Cas9) HCC cells were established with stable expression of Cas9 protein,and then specific gene knockout was performed using sgRNA targeting Trim72 gene.After obtaining the Hepa1-6 (Trim72-KO) cells,the metastasis and invasion abilities of the cells were evaluated by in vitro Transwell assay and in vivo subcutaneous lung metastasis examination.Results Hepa1-6 (Trim72-KO) cell line was successfully established by the CRISPR-Cas9 system.Transwell assay indicated that the mobility of Hepa1-6 (Trim72-KO) cells was increased compared to the control cells.Transwell assay indicated that the metastasis and invasion of Hepa1-6 (Cas9) HCC cells were enhanced after the knockout of Trim72 gene.The pathological examination of lung metastasis of subcutaneous tumor in vivo showed that the subcutaneously metastatic ability of Hepa1-6 (Trim72-KO) cells (the experimental group) was significantly stronger than Hepa1-6 (Cas9) cells (the control troup) that were not transferred to the corresponding sgRNA.Conclusions The trim72 gene knocked-out HCC cells were obtained by CRISPR-Cas9 system,which showed stronger metastasis and invasion abilities than the control cells.It is suggested that Trim72 gene may play an important role in the invasion and metastasis of HCC,and Trim 72 gene is expected to be a potential target for gene therapy of liver cancer.