Exosomes mediated transfer of lncRNA 91H may play a critical role in the development of CRC. However, few studies have proved the mechanism. So we performed this study to deeply explore the biological functions of exosomal 91H in the development and progression of CRC. The association between lncRNA 91H and exosomes was detected in vitro and vivo. Then RNA pulldown and RIP were used to detect how lncRNA 91H affect CRC IGF2 express. At last, clinic pathological significance of exosomal 91H was evaluated by Cox proportional hazards model. We found that serum lncRNA 91H expression was closely related to cancer exosomes in vitro and vivo which may enhance tumor-cell migration and invasion in tumor development by modifying HNRNPK expression. Then the clinic pathological significance of exosomal 91H was evaluated which demonstrated that CRC patients with high lncRNA 91H expression usually showed a higher risk in tumor recurrence and metastasis than patients with low lncRNA 91H expression (P < 0.05). All these data suggested that exosomal lncRNA 91H enhancing CRC metastasis by modifying HNRNPK expression might be an early plasma-based biomarker for CRC recurrence or metastasis. Further large-scale studies are needed to confirm our findings.

91H, a long non-coding antisense transcripts located on the position of the H19/IGF2 locus had been suggested to play a critical role in tumour development. However, little study had proved the mechanism in colorectal cancer (CRC). Hence, we performed this study to deeply explore the mechanism of lncRNA 91H in tumour progression. The expression of lncRNA 91H was first detected in CRC tissues and cells which was higher in vitro and in vivo than normal cells or tissues and CRC patients with high lncRNA 91H expression usually had a high risk in tumour metastasis (p < .05). Then, monodansylcadaverine (MDC) staining, scratch wound, migration and invasion assays were conducted which showed to that reduced lncRNA 91H would greatly affect tumour migration, invasion and autophagy. Finally, by RNA pull down and RNA-binding protein immunoprecipitation (RIP) assay, a significant interaction was found between lncRNA 91H and IGF2BP2 which was proved to play an important role in CRC IGF2 expression. All these results suggested lncRNA 91H promotes IGF2 expression by interacting with IGF2BP2 which would provide a new strategy in finding potential CRC diagnostic biomarkers and therapeutic targets.

To characterize species of viral mRNA transcripts generated during respiratory syncytial virus (RSV) infection, human fibroblast-like MRC-5 lung cells were infected with subgroup A RSV for 6, 16 and 24 hours. In addition, we characterised the viral transcriptome in infected Calu-3 lung epithelial cells at 48 hours post infection. Total RNA was harvested and polyadenylated mRNA was enriched and sequenced by direct RNA sequencing using an Oxford nanopore device. This platform yielded over 450,000 direct mRNA transcript reads which were mapped to the viral genome and analysed to determine the relative mRNA levels of viral genes using our in-house ORF-centric pipeline. We examined the frequency of polycistronic readthrough mRNAs were generated and assessed the length of the polyadenylated tails for each group of transcripts. We show a general but non-linear decline in gene transcript abundance across the viral genome, as predicted by the model of RSV gene transcription. However, the decline in transcript abundance is not uniform. The polyadenylate tails generated by the viral polymerase are similar in length to those generated by the host polyadenylation machinery and broadly declined in length for most transcripts as the infection progressed. Finally, we observed that the steady state abundance of transcripts with very short polyadenylate tails less than 20 nucleotides is less for N, SH and G transcripts in both cell lines compared to NS1, NS2, P, M, F and M2 which may reflect differences in mRNA stability and/or translation rates within and between the cell lines.

Septic disease usually results in delayed access to intensive care and poor outcomes in CRC patients. Studies have shown that T cells play important roles in CRC and sepsis immune systems. Hence, this study was performed to investigate the role of T cells and T-cell-related genes in CRC-related sepsis prognosis. Single-cell sequencing data from CRC and sepsis patients were first analysed to explore common T-cell signals, including those related to cellular communication and signalling pathways. Then, functional enrichment analysis and Mendelian randomization (MR) analysis were conducted on marker genes of T cells to identify the key genes and their effects on septic CRC. The expression of key genes and their associations with CRC prognosis were validated in 32 blood samples from CRC patients with sepsis. Compared with that in the negative control group, CD4_Naive cells infiltration was significantly lower in the combined single-cell sequencing data analysis of CRC and sepsis patients (p < 0.05). Our MR analysis and clinical sample verification results revealed that a high FMO4 gene was negatively associated with CD4_Naive cells infiltration and related to poor prognosis in septic patients with CRC (p < 0.05). The functional enrichment analysis of FMO4 revealed that FMO4 participated mainly in xenobiotic catabolic processes and taurine and hypo-Taurine metabolism in septic CRC, which further inhibited the energy metabolic activity of CD4_Naive cells. The CD4_Naive cells related gene FMO4 appears to promote poor prognosis in septic CRC patients, suggesting that it is a promising candidate for therapeutic intervention.