Role of UPF1 in lncRNA-HEIH regulation for hepatocellular carcinoma therapy.

UPF1, a novel posttranscriptional regulator, regulates the abundance of transcripts, including long noncoding RNAs (lncRNAs), and thus plays an important role in cell homeostasis. In this study, we revealed that UPF1 regulates the abundance of hepatocellular carcinoma upregulated EZH2-associated lncRNA (lncRNA-HEIH) by binding the CG-rich motif, thereby regulating hepatocellular carcinoma (HCC) tumorigenesis. UPF1-bound lncRNA-HEIH was susceptible to degradation mediated by UPF1 phosphorylation via SMG1 and SMG5. According to analysis of RNA-seq and public data on patients with liver cancer, the expression of lncRNA-HEIH increased the levels of miR-194-5p targets and was inversely correlated with miR-194-5p expression in HCC patients. Furthermore, UPF1 depletion upregulated lncRNA-HEIH, which acts as a decoy of miR-194-5p that targets GNA13, thereby promoting GNA13 expression and HCC proliferation. The UPF1/lncRNA-HEIH/miR-194-5p/GNA13 regulatory axis is suggested to play a crucial role in cell progression and may be a suitable target for HCC therapy.

Widespread 8-oxoguanine modifications of miRNA seeds differentially regulate redox-dependent cancer development.

Oxidative stress contributes to tumourigenesis by altering gene expression. One accompanying modification, 8-oxoguanine (o8G) can change RNA-RNA interactions via o8G•A base pairing, but its regulatory roles remain elusive. Here, on the basis of o8G-induced guanine-to-thymine (o8G > T) variations featured in sequencing, we discovered widespread position-specific o8Gs in tumour microRNAs, preferentially oxidized towards 5' end seed regions (positions 2-8) with clustered sequence patterns and clinically associated with patients in lower-grade gliomas and liver hepatocellular carcinoma. We validated that o8G at position 4 of miR-124 (4o8G-miR-124) and 4o8G-let-7 suppress lower-grade gliomas, whereas 3o8G-miR-122 and 4o8G-let-7 promote malignancy of liver hepatocellular carcinoma by redirecting the target transcriptome to oncogenic regulatory pathways. Stepwise oxidation from tumour-promoting 3o8G-miR-122 to tumour-suppressing 2,3o8G-miR-122 occurs and its specific modulation in mouse liver effectively attenuates diethylnitrosamine-induced hepatocarcinogenesis. These findings provide resources and insights into epitranscriptional o8G regulation of microRNA functions, reprogrammed by redox changes, implicating its control for cancer treatment.

I-CARE: Feasibility, Acceptability, and Appropriateness of a Digital Health Intervention for Youth Experiencing Mental Health Boarding.

PURPOSE: Youth with suicidality requiring psychiatric hospitalization may first experience boarding at acute care hospitals. Given infrequent provision of therapy during this period, we developed a modular digital intervention (I-CARE; Improving Care, Accelerating Recovery and Education) to facilitate delivery of evidence-based psychosocial skills by non-mental health clinicians. This pilot study describes changes in emotional distress, severity of illness, and readiness for engagement following I-CARE participation, and evaluates the feasibility, acceptability, and appropriateness of I-CARE. METHODS: A mixed-methods approach was used to evaluate I-CARE, offered to youth 12-17 years from 11/21 to 06/22. Changes in emotional distress, severity of illness, and engagement readiness were evaluated using paired t-tests. Semistructured interviews with youth, caregivers, and clinicians were conducted concurrently with collection of validated implementation outcome measures. Quantitative measure results were linked to interview transcripts, which were analyzed thematically. RESULTS: Twenty-four adolescents participated in I-CARE; median length of stay was 8 days (IQR:5-12 days). Emotional distress decreased significantly by 6.3 points (63-point scale) following participation (p = .02). The increase in engagement readiness and decrease in youth-reported illness severity were not statistically significant. Among 40 youth, caregivers, and clinicians who participated in the mixed-methods evaluation, 39 (97.5%) rated I-CARE as feasible, 36 (90.0%) as acceptable, and 31 (77.5%) as appropriate. Adolescents' prior knowledge of psychosocial skills and clinicians' competing demands were reported barriers. DISCUSSION: I-CARE was feasible to implement and youth reported reduced levels of distress following participation. I-CARE has the potential to teach evidence-based psychosocial skills during boarding, which may provide a head-start on recovery before psychiatric hospitalization.

AGO-accessible anticancer siRNAs designed with synergistic miRNA-like activity.

Small interfering RNAs (siRNAs) therapeutically induce RNA interference (RNAi) of disease-causing genes, but they also silence hundreds of seed-matched off-targets as behaving similar to microRNAs (miRNAs). miRNAs control the pathophysiology of tumors, wherein their accessible binding sites can be sequenced by Argonaute crosslinking immunoprecipitation (AGO CLIP). Herein, based on AGO CLIP, we develop potent anticancer siRNAs utilizing miRNA-like activity (mi/siRNAs). The mi/siRNAs contain seed sequences (positions 2-7) of tumor-suppressive miRNAs while maintaining perfect sequence complementarity to the AGO-accessible tumor target sites. Initially, host miRNA interactions with human papillomavirus 18 (HPV18) were identified in cervical cancer by AGO CLIP, revealing tumor-suppressive activity of miR-1/206 and miR-218. Based on the AGO-miRNA binding sites, mi/siRNAs were designed to target E6 and E7 (E6/E7) transcript with seed sequences of miR-1/206 (206/E7) and miR-218 (218/E7). Synergistic anticancer activity of 206/E7 and 218/E7 was functionally validated and confirmed via RNA sequencing and in vivo xenograft models (206/E7). Other mi/siRNA sequences were additionally designed for cervical, ovarian, and breast cancer, and available as an online tool (http://ago.korea.ac.kr/misiRNA); some of the mi/siRNAs were validated for their augmented anticancer activity (206/EphA2 and 206/Her2). mi/siRNAs could coordinate miRNA-like activity with robust siRNA function, demonstrating the potential of AGO CLIP analysis for RNAi therapeutics.