Abstract. Apigenin is a flavonoid belonging to the flavone structural class. It has been implicated as a chemopreventive agent against prostate and breast cancers. However, to the best of our knowledge, no published data are available regarding apigenin in colorectal cancer (CRC). The effects and mechanisms of apigenin on CRC may vary significantly. This study aimed to analyze the effects of apigenin on the growth of CRC xenografts in nude mice derived from SW480, as well as to investigate the underlying mechanisms. Whole-body fluorescence imaging is an inexpensive optical system used to visualize gene expression in small mammals using reporter genes, such as eGFP as a reporter. In our study, the expression of eGFP may reflect the size of the tumor. A terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay showed that apigenin promoted the apoptosis of CRC cells. Furthermore, the expression of five genes related to the proliferation and apoptosis of CRC, i.e., cyclin D1, BAG-1, Bcl-2, yrdC and Fas-associated protein with death domain (FADD), was detected by real-time quantitative RT-PCR. Among these genes, the up-regulated expression of FADD was noted in CRC xenograft tumors treated with apigenin. Immunohistochemistry and Western blotting confirmed the results at the protein level. Furthermore, Western blot analysis showed that apigenin induced the phosphorylation of FADD. Our findings suggest that apigenin enhances the expression of FADD and induces its phosphorylation, which may cause apoptosis of CRC cells and inhibition of tumor growth.

Background: The study of CTLA-4 inhibitors has been one of the hot spots in the field of tumor immunotherapy. As the most immunogenic subtype of breast cancer, Triple negative breast cancer (TNBC) has a great potential in the treatment strategy. The aim of this study was to explore the relevant genes and pathways of CTLA-4 in TNBC and to explore the prognostic value, so as to provide a theoretical basis for clinical studies. Materials and methods: We used the data from The Cancer Genome Atlas (TCGA) to analyze the expression of CTLA-4 in different types of breast cancer, and analyzed the TNBC data of CTLA-4 related co-expression genes by WGCNA and enrichment analysis. LncRNA-miRNA-CTLA-4 network was constructed to explore the immune infiltration and immune checkpoint associated with CTLA-4. The effect of CTLA-4 on clinical outcomes in TNBC patients was also evaluated. Finally, we used data from GEO database to verify the differences of CTLA-4 in different molecular types of breast cancer and related prognostic results. Results: CTLA-4 was significantly higher in TNBC than in Luminal subtype and Her-2 + subtype (P=0.019 and P<0.001, separately), and was significantly higher in ER and PR negative samples than in ER and PR positive samples (P<0.001). CTLA-4 related genes mainly enriched in biological process of leukocyte differentiation, regulation of leukocyte activation and T cell activation. Hsa-mir-92a was found to be a survival significance marker associated with CTLA-4 and lncRNA-miRNA-CTLA-4 network was constructed. The results of immune infiltration analysis showed that CTLA-4 was mainly related with T cell (r=0.74). For immune checkpoints analysis, CTLA-4 was mainly related to PDCD1(r=0.72) and CD28(r=0.64). In TNBC, high expression of CTLA-4 is related to good survival (P=0.0061). Results consistent with previous analysis were obtained in the GEO database, the expression of CTLA-4 in TNBC was significantly higher than that in non-TNBC (p<0.001), CTLA-4 was associated with favorable survival of TNBC (p<0.001). Conclusion: Among all types of breast cancer, the expression of CTLA-4 was the highest in TNBC.CTLA-4 in TNBC can be regulated by hsa-mir-92a to form ceRNA networks and influence the prognosis of TNBC patients through the leukocyte differentiation, regulation of leukocyte activation and T cell activation pathway.

Background and Objective: Protein expression in colon and rectal cancer (CRC) and paired normal tissues was examined by two-dimensional gel electrophoresis (2-DE) to identify differentially expressed proteins. Materials and Methods: Five fresh colorectal cancer and paired adjacent normal tissues were obtained and differentially expressed protein spots were determined using PDQuest software, with identification on the basis of MALDI-TOF mass spectra. Results: Compared with normal colorectal mucosa, protein abnormal expression of 65 spots varying more than 1.5 times were found in 2-DE gels from colorectal cancer samples (P<0.05); forty-two proteins were up-regulated and 23 were down-regulated; twelve protein spots were identified using mass spectrometry, of which 8 were up-regulated, includimng HSPB1and Annexin A4, while 4 were down-regulated, the results being consistent with Western blot findings. Conclusions: Two-dimensional electrophoresis reference maps for CRC tissues and adjacent normal mucosa (NMC) were established and 12 differentially expressed proteins were identified. Up-regulated HSPB1 and Annexin A4 may play many important roles in the pathogenesis of colorectal cancer. cancer. In this study, the differentially expressed proteins between CRC and normal tissues were identified and differential protein expression profiles were established by proteomic approach, which provides a theoretical basis and foundation for further searching for the potential biomarkers and therapeutic targets relevant to human CRC occurrence and development.