Serum MicroRNAs Related with Chemoradiotherapy Resistance in Advanced-Stage Cervical Squamous Cell Carcinoma

Abstract

Objective: To investigate the serum microRNAs as biomarkers in predicting chemoradiotherapy resistance in advanced-stage cervical squamous cell carcinoma (ACSCC) patients.

Methods: Serum samples were collected from International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IIIB cervical squamous cell carcinoma patients treated with platinum based Concomitant Chemoradiotherapy (CCRT) in our hospital during September 2013 to November 2015. Twenty well-matched samples (10 resistant and 10 sensitive) were chosen to screen the miRNA expression profile using serum samples pooled with microarrays. miRNAs expressed significantly different between two groups were further verified in 131 patients (29 resistant and 102 sensitive) serum samples with TaqMan Real-time PCR. The AUC was used to evaluate the accuracy of the biomarkers for prediction.

Results: MiR-136-5, miR-152-3p and miR-206 were expressed significantly different between sensitive and resistant groups. Results of 131 patients verification showed that the levels of miR-206 in sensitive samples and resistant samples were 2.715±0.2115 and 14.64±1.184, respectively, which was significantly different (P<.0001), while miR-136-5p and miR-152-3p could not be tested without pre-amplification reactions. Univariate analysis revealed that miR-206 expression was significantly associated with patients' DFS. Multivariate analysis demonstrated that miR-206 expression, tumor differentiation and pelvic lymph nodes metastasis were the independent prognostic factors associated with DFS in this cohort (P=.008, 0.000, 0.000, respectively). The probability of the prognostic accuracy of miR-206 expression in predicting chemoradiotherapy sensitivity of ACSCC patients was 91.3% (79.3% sensitivity and 92.2% specificity).

Conclusion: Serum miR-206 is a powerful tool in predicting chemoradiotherapy sensitivity in ACSCC patients.

Figure 1

Flow chart of the screening and verifying processes. TaqMan Real-time PCR microRNA Array (Card A) (Applied Biosystems, CA) representing 212 mature miRNAs was used to identify differentially expressed miRNAs from 20 serum samples (10 from sensitive group vs. 10 from resistant group). Take miRNA expression in sensitive group as standard, a total of 62 miRNAs were up-regulated expression while 150 miRNAs were down-regulated expression in resistant group. Among these miRNAs, 3 miRNAs expressed statistically significantly different between two groups. MiR-136 was down-regulated expression in resistant group while miR-152 and miR-206 was up-regulated expression. Three candidate miRNAs were further validated in 131 independent serum samples.

Figure 2

The scatter diagrams of serum miR-206 in 131 ACSCC patients. Resistant group includes 29 cases, sensitive group includes 102 cases.

Figure 3

The level of serum miR-206 was associated with disease free survival.

Figure 4

ROC analysis for predicting CCRT sensitivity of ACSCC patients: (A) ROC curve for miR-206 yielded area under the curve (AUC) of 91.3%, the sensitivity of 79.3% and specificity of 92.2% in predicting chemoradiotherapy sensitivity; (B) ROC curve for tumor differentiation (TD) and pelvic lymph nodes metastasis (PLNM) yielded an AUC of 76.5%, the sensitivity of 82.8% and specificity of 57.8% in predicting chemoradiotherapy sensitivity.