Assessment of the prognostic and clinicopathological significance of HOXA-AS2 in human cancers: a systematic review and meta-analysis

BACKGROUND: Numerous studies have reported that abnormally HOXA cluster antisense RNA 2 (HOXA-AS2) expression plays a critical role in various cancers. Thus, we performed this meta-analysis to comprehensively evaluate the prognostic value of HOXA-AS2 in human cancers. METHODS: Databases, including PubMed, Web of Science, Embase, China National Knowledge Infrastructure, and Wanfang Data, were searched to retrieve articles on HOXA-AS2 and the prognosis of cancer patients, which were then screened. The association between HOXA-AS2 and overall survival (OS) and the clinicopathological characteristics of patients with cancers were assessed using hazard ratios (HRs) and odds ratios (ORs) combined with 95% confidence intervals (CIs). A subgroup analysis and the Begg test were used to assess the risk of bias of the included studies. Data from The Cancer Genome Atlas (TCGA) were analyzed to verify the results, and the potential regulation mechanism of HOXA-AS2 in cancers was revealed by an immune analysis. RESULTS: A total of 17 articles, comprising 1,176 patients, were included in this meta-analysis. The results showed that high HOXA-AS2 expression was associated with worse OS, advanced tumor node metastasis (TNM) stage, larger tumor size, lymph node metastasis, and distant metastasis in cancer patients but was not related to age, sex, or poor histological grade. The results of the analysis of TCGA data further supported our findings. Additionally, the immune analysis revealed that the expression of HOXA-AS2 was associated with immune cell infiltration and various immune checkpoints. CONCLUSIONS: In summary, our results suggest that the high expression of HOXA-AS2 is associated with poor prognosis and the clinicopathological characteristics of cancer patients; thus, it could serve as a prognosis biomarker and therapeutic target for various cancers. However, the small sample size of this study and the inclusion of participants of a single race might have affected the generalizability of our findings. Thus, large-sample, multicenter studies need to be conducted to further evaluate the prognostic role of HOXA-AS2.