FHIP1A-DT is a potential novel diagnostic, prognostic, and therapeutic biomarker of colorectal cancer: A pan-cancer analysis

FHIP1A-DT is a long non-coding RNA (lncRNA) obtained by divergent transcription whose mechanism in pan-cancer and colorectal cancer (CRC) is unclear. We elucidated the molecular mechanism of FHIP1A-DT through bioinformatics analysis and in vitro experiments. Pan-cancer and CRC data were downloaded from the University of California, Santa Cruz (UCSC) Genome Browser and the Cancer Genome Atlas (TCGA). We analyzed FHIP1A-DT expression and its relationship with clinical stage, diagnosis, prognosis, and immunity characteristics in pan-cancer. We also analyzed FHIP1A-DT expression in CRC and explored the relationship between FHIP1A-DT and CRC diagnosis and prognosis. Then, we analyzed the correlation between FHIP1A-DT and drug sensitivity, immune cell infiltration, and the biological processes involved in FHIP1A-DT. The competing endogenous RNA (ceRNA) regulatory network associated with FHIP1A-DT was explored. External validation was conducted using external data sets GSE17538 and GSE39582 and in vitro experiments. FHIP1A-DT expression was different in pan-cancer and had excellent diagnostic and prognostic capability for pan-cancer. FHIP1A-DT was also related to the pan-cancer tumor mutation burden (TMB), microsatellite instability (MSI), and immune cell content. FHIP1A-DT was downregulated in CRC, where patients with CRC with low FHIP1A-DT expression had a worse prognosis. A nomogram combined with FHIP1A-DT expression demonstrated excellent predictive ability for prognosis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that FHIP1A-DT was associated with epigenetic modification and regulated many cancer-related pathways. The ceRNA network demonstrated the potential gene regulation of FHIP1A-DT. FHIP1A-DT was related to many chemotherapeutic drug sensitivities and immune cell infiltration such as CD4 memory resting T cells, monocytes, plasma cells, neutrophils, and M2 macrophages. The FHIP1A-DT expression and prognostic analysis of GSE17538 and GSE39582, and qPCR yielded similar external verification results. FHIP1A-DT was a novel CRC-related lncRNA related to CRC diagnosis, prognosis, and treatment sensitivity. It could be used as a significant CRC biomarker in the future.