ABSTRACT
Introduction: The standard treatment for head and neck squamous cell carcinoma (HNSCC) is cisplatin chemoradiotherapy. One of the main treatment adverse reactions is nephrotoxicity, for which there is currently no adequate specific and sensitive biomarker. Thus, this study aimed to evaluate the use of microRNAs (miRNAs) as renal biomarker candidates. Methods: This was a retrospective cohort study. Nephrotoxicity was assessed through blood samples collected before and 5 days (D5) after chemotherapy. MiRNAs were extracted from urine samples collected at baseline and D5, and RNA sequencing identified miRNAs differentially expressed between participants with and without cisplatin-induced nephrotoxicity. Results: A total of 49 participants were included (n = 49). A significant difference was seen between the two groups for traditional renal markers (serum creatinine and creatinine clearance) and for the acute kidney injury (AKI) categories. Among the six miRNAs evaluated as biomarkers, four were upregulated (hsa-miR-6729-5p, hsa-miR-1238-5p, hsa-miR-4706, and hsa-miR-4322) and two were downregulated (hsa-miR-6805-5p and hsa-miR-21-5p), but only hsa-miR-6805-5p had a significant difference (p < 0.0001). Its receiver operating characteristic curve revealed excellent specificity (0.920) for its expression fluctuation assessment, while its absolute expression in D5 showed greater sensitivity (0.792). Conclusion: So, the integrated use of these two parameters seems to be an interesting approach for AKI.
ABSTRACT
The microRNA (miRNA) expression profile by qRT-PCR depends directly on the most appropriate normalization strategy adopted; however, currently there is no universally adequate reference gene. Therefore, this study aimed to determine, considering RNA-Seq results, the most adequate endogenous normalizer for use in the relative quantification of urine miRNAs from head and neck cancer patients, treated with cisplatin chemoradiotherapy. The massive sequencing was performed to identify the miRNAs differentially expressed between the group with cisplatin nephrotoxicity (n = 6) and the one without (n = 6). The candidate endogen normalizer was chosen according to four criteria: (1) the miRNA must be expressed in most samples; (2) the miRNA must have a fold change value between 0.99 and 1.01; (3) the miRNA must have a p-value ≥ 0.98; and (4) the miRNA must not be commented on by the final GeneGlobe (Qiagen, Hilden, Germany) analysis. Four miRNAs met all the criteria (hsa-miR-363-5p, hsa-miR-875-5p, hsa-miR-4302, and hsa-miR-6749-5p) and were selected for validation by qRT-PCR in a cohort of 49 patients (including the 12 sequencing participants). Only hsa-miR-875-5p was shown to be an adequate normalizer for the experimental condition under investigation, as it exhibited invariant expression between the two groups.
