Expression profiles and gene set enrichment analysis of the transcriptomes from the cancer tissue, white adipose tissue and paracancer tissue with colorectal cancer.

Background: Colorectal cancer (CRC) is one of the most common cancers worldwide and is related to diet and obesity. Currently, crosstalk between lipid metabolism and CRC has been reported; however, the specific mechanism is not yet understood. In this study, we screened differentially expressed long non-coding RNAs (lncRNAs) and mRNAs from primary cancer, paracancer, and white adipose tissue of CRC patients. We screened and analyzed the genes differentially expressed between primary and paracancer tissue and between paracancer and white adipose tissue but not between primary and white adipose tissue. According to the results of the biological analysis, we speculated a lncRNA (MIR503HG) that may be involved in the crosstalk between CRC and lipid metabolism through exosome delivery. Methods: We screened differentially expressed long non-coding RNAs (lncRNAs) and mRNAs from primary cancer, paracancer, and white adipose tissue of CRC patients. We screened and analyzed the genes differentially expressed between primary and paracancer tissue and between paracancer and white adipose tissue but not between primary and white adipose tissue. Results: We speculated a lncRNA (MIR503HG) that may be involved in the crosstalk between CRC and lipid metabolism through exosome delivery. Conclusions: In this study, the findings raise the possibility of crosstalk between lipid metabolism and CRC through the exosomal delivery of lncRNAs.

[Experimental research of neutrophil gelatinase-associated lipocalin siRNA encapsulated by urocanic acid-coupled chitosan on colon cancer cells].

OBJECTIVE: To explore the impact of neutrophil gelatinase-associated lipocalin (NGAL) knockdown by NGAL siRNA encapsulated with urocanic acid-modified chitosan nanoparticles (UAC) on the proliferation, migration and apoptosis of human colon cancer cells. METHODS: NGAL siRNA was encapsulated by UAC and chitosan (CTS) respectively, and then was transfected into human colon cancer cell lines HT29. The NGAL mRNA was detected by real-time quantitative PCR (RT-QPCR). Relationships of NGAL gene silencing with the proliferation, migration and apoptosis of HT29 cell were analyzed. RESULTS: Under the fluorescence microscope, the transfection efficiency of siRNA in UAC group was (37.52±7.17)%, which was significantly higher than (11.32±3.39)% in CTS group (t=6.102, P=0.005). Forty-eight hours after transfection, RT-QPCR examination showed that the level of NGAL mRNA expression was 0.350 in UAC group and 0.529 in CTS group with significant difference (t=-3.743, P=0.02), meanwhile both levels were significantly lower as compared to control group(F=163.538, P<0.001). Proliferation analysis revealed that after silencing NGAL gene, proliferation rate of UAC group and CTS group was slightly lower than control group, and no significant differences were found (F=9.520, P=0.438). However, migration assay demonstrated that the 24-hour migration rate of UAC group and CTS group was significantly lower than that of control group (F=6.756, P=0.029), meanwhile the migration rate of UAC group was slightly lower than that of CTS group [(77.90±7.14)% vs. (87.67±3.98)%, t=-1.704, P=0.164]. Apoptosis detection revealed that the apoptosis rate in UAC group was significantly higher than that in CTS group and the control group 2 days after transfection [(15.800±1.054)% vs. (12.900±0.656)%, (11.933±1.914)%, F=7.004, P=0.027]. CONCLUSIONS: The encapsulated ability and transfection efficiency of chitosan modified by urocanic acid elevate significantly. Silencing NGAL gene by UAC carrier can down-regulate the expression of NGAL mRNA in HT29 colon cell line, inhibit their migration and facilitate their apoptosis.