ABSTRACT
Objective@#To explore the method of extracting chaperone antigen peptide complexes from gastric cancer stem cells and its immune function.@*Methods@#Gastric cancer stem cells and gastric cancer cells were screened by low temperature ultrasonic lysis. After salting out and dialysis, the lysate supernatant was processed with SDS-PAGE to analyze the expression of chaperone antigen peptide complexes, and then was separated and purified with CNBr-activated SepharoseTM 4B. Reverse high pressure liquid chromatography (HPLC), SDS-PAGE and Western blotting were used to analyze the purity and nature of the acquired albumen. Lymphocyte proliferation assay and lymphocytotoxicity assay were used to ditermine the immunological activity of the chaperone-antigen peptide complexes.@*Results@#The chaperone antigen peptide complexes of gastric cancer stem cells were prepared and identified successfully, of which the main components were the antigen peptides of HSP60, HSP70, HSP90 and HSP110. 0.75 μg and 1.00 μg HSP70-antigen peptide and 1.00 μg HSP90-antigen peptide activated lymphocytes significantly. Their A490 values were 0.26±0.03, 0.45±0.05 and 0.32±0.04, respectively, while the corresponding doses of HSP60-antigen peptide and HSP110-antigen peptide did not activate lymphocytes. The killing rates of 1.00 μg HSP70-antigen peptide and 1.00 μg HSP70 were (45.0±2.0)% and (16.0±2.0)%, respectively, showing a significant difference (P=0.012). Similarly, the killing rates of 1.00 μg HSP90-antigen peptide and 1.00 μg HSP90 were (36.0±5.0)% and (13.0±4.0)%, respectively, also showing a significant difference (P=0.048).@*Conclusions@#The amount of chaperone antigen peptide complexes in gastric cancer cells is extremely low, but it is obviously increased in gastric cancer stem cells. After purification, the chaperone antigen peptide complexes with high purity can be prepared. The extracted chaperone antigen peptide complexes have stronger immunogenicity, and can be used to make tumor vaccine in vitro, which may have a good application value in the targeted therapy of gastric cancer.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of microRNA(miRNA)-29b on the proliferation and migration of breast cancer cells and its molecular mechanism.</p><p><b>METHODS</b>The recombinant lentiviral expression vector (lenti-miRNA-29b) was constructed and transfected into 293T cells to obtain lentivirus particles that were used to infect breast cancer MCF-7 cells. Transfection efficiency of lenti-miRNA-29b in MCF-7 cells was identified by the expression of green fluorescent protein (GFP). The expression of miRNA-29b was detected by real-time PCR. The cell proliferation and migration were detected by CCK8 assay and Transwell assay, respectively. The bioinformatics softwares were used to predict and screen the downstream target genes regulated by miRNA-29b, which were verified by double luciferase reporter gene assay, RT-PCR and Western blot. The effects of screened target gene RTKN on the growth and migration of MCF-7 cells were verified by RTKN siRNA.</p><p><b>RESULTS</b>Recombinant lentiviral expression vector of miRNA-29b were successfully constructed. About 90% and 60% of the breast cancer cells showed green fluorescence in lenti-miRNA-29b and lenti-miRNA-NC groups, respectively. The expression of miRNA-29b in lenti-miRNA-29b group increased significantly compared with the lenti-miRNA-NC group and blank control group (all<0.05); the proliferation and migration ability of MCF-7 cells significantly reduced compared with the control group (all<0.05). The screening with bioinformatics softwares found that the 3'UTR coding region RTKN had the binding site to miRNA-29b; the dual luciferase reporter gene assay showed that the luciferase activity decreased significantly after the MCF-7 cells were co-transfected with wild type RTKN-WT-3'UTR and miRNA-29b mimics report gene vector (<0.05). The RTKN proteins in MCF-7 cells were significantly decreased after transfection with siRNA-RTKN, and the proliferation and migration ability of MCF-7 cells were significantly reduced (all<0.05).</p><p><b>CONCLUSIONS</b>MiRNA-29b can inhibit the proliferation, invasion and metastasis of breast cancer cells by inhibiting the expression of RTKN.</p>
ABSTRACT
MicroRNAs are a class of small (-22nt) non-coding RNAs that bind to the 3' untranslated regions (3'-UTRs) of their target mRNAs in a complementary or partially complementary manner via the seed sequence in their 5'-region to regulate biological effect. MicroRNAs also expressin malignant tumors and have close relations with occurrence, development and other biological characteristics of tumor. The effect of radiotherapy and the prognosis of cancer patients are limited and influenced by radioresistant all the time. In recent years, the application of microRNAs to improve the radiation sensitivity of tumor cells is a new field in tumor biotherapy. This paper mainly reviews the identification of related microRNAs participating in and regulating the formation of radiosensitivity/radioresistent, and the research progress of their possible mechanisms.
Subject(s)
Humans , MicroRNAs , Metabolism , Therapeutic Uses , Neoplasms , Metabolism , Radiotherapy , Prognosis , RNA, Messenger , Metabolism , Radiation ToleranceABSTRACT
With the continuous development of tumor immunology,cancer vaccines have become a hot spot of tumor immunotherapy.Companion member antigen peptide tumor vaccine attracts widely attention because of its chemical stability,easy preparation and no carcinogenic potential advantage.Companion member antigen peptide tumor vaccine may work through many kinds of ways including the function of antigen presenting,enhancing the body's non-specific line of anti-tumor mechanisms and activating the tumor-specific immune mechanism.Its different anti-tumor mechanisms merits and so on will have positive function in the tumor clinical immunity treatment.