Letter to the Editor: Beyond the mechanism: MiR-206 as a prognostic biomarker and therapeutic target in hepatocellular carcinoma after incomplete radiofrequency ablation

Abstract

Lu et al in the World Journal of Gastrointestinal Oncology provided compelling evidence that micro RNA-206 (miR-206) suppressed hepatocellular carcinoma recurrence after incomplete radiofrequency ablation by targeting the hypoxia-inducible factor-1α and its downstream glycolytic target 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3. While the mechanistic insights provided are valuable, the clinical translational potential of miR-206 warrants greater emphasis, particularly given the current limitations of existing biomarkers, such as alpha-fetoprotein and protein induced by vitamin K absence or antagonist-II, which often lack sufficient sensitivity and specificity for predicting recurrence after ablation. We propose the translational potential may lie in exploring miRNA-206 as a dual-purpose tool: A preoperative prognostic biomarker for risk stratification and a post-ablation therapeutic agent delivered via advanced nanocarriers to the periablational zone. Future studies should investigate this potential duality to shift hepatocellular carcinoma management toward precision interventions.

Key Words: MicroRNA-206; Hepatocellular carcinoma; Radiofrequency ablation; Prognostic biomarker; Nanotherapy; Precision medicine

Core Tip: This commentary extends the findings from a recent article by proposing two concrete translational applications for microRNA-206 in the management of hepatocellular carcinoma: (1) As a preoperative biomarker to stratify recurrence risk before ablation; and (2) As a therapeutic agent administered locally by a nanocarrier during or after radiofrequency ablation to prevent recurrence. The potential duality of microRNA-206 could transform the standard of care for patients with high-risk hepatocellular carcinoma.

TO THE EDITOR

Lu et al[1] in the World Journal of Gastrointestinal Oncology presented a comprehensive, multitiered investigation elucidating a novel molecular mechanism underlying the recurrence of hepatocellular carcinoma after incomplete radiofrequency ablation (iRFA). They found that microRNA-206 (miR-206) directly targeted hypoxia-inducible factor-1α (HIF-1α) to suppress 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3-mediated glycolysis and angiogenesis. Their study provided significant insight into the metabolic reprogramming driving post-ablation tumor progression. The methodology undertaken by Lu et al[1] was particularly robust in its integration of clinical observations with in vitro functional assays and in vivo validation in a rabbit VX2 model. They detected decreased serum miR-206 in clinical samples as well as increased HIF-1α levels and glycolytic markers in patients with iRFA to establish a strong translational link. Subsequent in vitro experiments convincingly showed that miR-206 overexpression reversed the protumorigenic effects of thermal stress on endothelial cells while the dual-luciferase assay provided direct evidence of the miR-206/HIF-1α interaction.

MiR-206 is one of the most studied and well-characterized microRNAs. It was initially recognized for its unique expression in skeletal muscle[2]. Over time miR-206 was found to be expressed in various cancer types with roles in carcinogenesis. It is a potential prognostic marker and novel therapeutic approach[3]. Multiple studies focusing on hepatocellular carcinoma have demonstrated that miR-206 exerts tumor suppressive effects through diverse mechanisms, including modulation of tumor-associated macrophages[4], attenuation of tumor growth factor beta 1 overproduction[5], and regulation of key enzymes in cholesterol synthesis and the pentose phosphate pathway[6]. The novel mechanistic role of miR-206 after ablation first proposed by Lu et al[1] has led us to highlight and expand upon two critical translational implications that could guide future research toward tangible clinical applications.

Currently, it is unknown whether preoperative miR-206 levels can predict the risk of recurrence after radiofrequency ablation (RFA). Data from a prospective early-stage cohort indicate a cumulative recurrence rate of approximately 67% alongside a 5-year survival rate of only 41%[7], underscoring the urgent need for reliable biomarkers. The observed inverse correlation between serum miR-206 levels and poor clinical outcomes suggests that miR-206 may serve as a promising prognostic and predictive biomarker[8]. This concept has become increasingly important in the management of several solid tumors[9]. If patients with low miR-206 expression are predisposed to aggressive disease or treatment resistance, then miR-206 could stratify patients before undergoing RFA. Patients with low miR-206 would be classified as high risk and would be eligible for more extensive ablation margins, initial combination therapy (e.g., RFA + transarterial chemoembolization), or closer postoperative surveillance. Validating miR-206 in a prospective cohort as a liquid biopsy biomarker could personalize initial treatment strategies.

MiR-206 has potential as a novel therapeutic agent. Lu et al[1] demonstrated that miR-206 mimics efficiently suppressed tumor phenotypes in vitro. However, a major challenge in microRNA therapy is targeted, efficient, and stable delivery in vivo[10]; nanocarrier microRNA delivery in oncology must seek to protect, target, and controllably release microRNAs to reprogram cancer pathways[11]. Therefore, we propose that the microenvironment after ablation may be uniquely suited for local therapeutic intervention because the ablation cavity created by RFA could serve as a reservoir for sustained-release drug delivery systems. Future studies should explore the development of miR-206-loaded nanoparticles or hydrogels that can be injected locally during the RFA procedure considering the recurrence mechanisms and intervention strategies after RFA. High local concentrations of miR-206 could be achieved in the peri-ablational zone to inhibit residual HIF-1α-driven glycolysis and angiogenesis while minimizing systemic off-target effects.

The integrated approach may not only improve recurrence prediction but also directly target residual disease, thereby potentially enhancing overall survival in HCC management. We still acknowledge, along with Lu et al[1], that there were limitations inherent in their study (i.e., modest clinical sample size and the absence of in vivo gain/loss-of-function rescue experiments). Furthermore, challenges such as variability in circulating microRNA assays and delivery barriers in nanotherapy also need consideration.

CONCLUSION

Lu et al[1] made a substantial contribution by defining the tumor-suppressive role of miR-206 after iRFA. Their mechanistic findings opened the door to transformative clinical applications that extend beyond biological understanding. We propose that the next logical steps involve translational research to develop miR-206 as both a biomarker for risk stratification and a therapeutic agent. Pursuing these directions could ultimately change the clinical management paradigm for patients undergoing liver tumor ablation.