Upregulation of Heat Shock Proteins (HSPA12A,HSP90B1, HSPA4, HSPA5 and HSPA6) in Tumour Tissues Is Associated with Poor Outcomes from HBV-Related Early-Stage Hepatocellular Carcinoma

Background: Heat shock proteins (HSPs) are overexpressed in human hepatocellular carcinoma (HCC) tissue and correlate with aggressiveness and prognosis of HCC.Methods: Using the {"type":"entrez-geo","attrs":{"text":"GSE14520","term_id":"14520"}}GSE14520 microarray expression profile from Gene Expression Omnibus, we compared HSP gene expression between tumour and non-tumour tissues and correlated this with outcomes in HCC patients.Results: We analysed 220 hepatitis B virus (HBV)-related HCC patients and 25 HSPs in this study. With the exception of HSPA4L, HSPA12A and HSPB8, members of the HSP family, including HSPH1, HSPBP1, HSPA1A, HSPA1B, HSPA1L, HSPA2, HSPA4, HSPA5, HSPA8, HSPA9, HSPAA1, HSPAB1, HSPA14, HSPB11, HSPA13, HSP90B1 and HSPBAP1, were all overexpressed in tumour tissues (all P < 0.001). In contrast, HSPB6, HSPB7, HSPA6, HSPB2 and HSPB3 were upregulated in non-tumour tissues (all P < 0.001). Multivariate analysis showed that cirrhosis (HR = 5.282, 95% CI = 1.294-21.555, P = 0.02), Barcelona Clinic liver cancer (BCLC) staging (HR = 2.151, 95% CI = 1.682-2.750, P < 0.001), HSPA12A (HR = 1.042, 95% CI = 1.003-1.082, P = 0.033) and HSP90B1 (HR = 1.001, 95% CI = 1.000-1.001, P = 0.011) were negatively associated with survival of HBV-related HCC patients. Furthermore, advanced BCLC staging (HR = 1.797, 95% CI = 1.439-2.244, P < 0.001) was also associated with earlier recurrence of HCC. The high expression of HSPA4 (HR = 1.002, 95% CI = 1.000-1.004, P = 0.019), HSPA5 (HR = 1.0, 95% CI = 1.0-1.0, P = 0.046) and HSPA6 (HR = 1.008, 95% CI = 1.001-1.015, P = 0.021) was similarly associated with HCC recurrence.Conclusions: The expression of most HSPs was higher in tumour tissues than in non-tumour tissues. High BCLC staging scores, advanced cirrhosis and the overexpression of HSPA12A and HSP90B1 might be associated with poor survival from HCC, whereas high levels of HSPA4, HSPA5 and HSPA6 might be associated with earlier recurrence of HCC.     

Circular RNA circ_ASAP2 promotes cell viability,migration, and invasion of gastric cancer cells by regulating the miR-770-5p/CDK6 axis

Background: Gastric cancer (GC) is one of the most common causes of cancer death. {"type":"entrez-geo","attrs":{"text":"GSE83521","term_id":"83521"}}GSE83521 microarray analysis suggested that circular RNA circ_ASAP2 (hsa_circ_0008768) expression was increased in GC tissues. However, the molecular mechanism of circ_ASAP2 remains unknown. Methods: Expression levels of circ_ASAP2, microRNA-770-5p (miR-770-5p), and the cyclin-dependent kinase 6 (CDK6) were detected by using real time PCR (RT-PCR). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and transwell assays were applied to explore cell viability, migration, and invasion, respectively. The interactions between miR-770-5p and circ_ASAP2 or CDK6 was predicted by using Starbase software, and then confirmed by luciferase reporter assay. Xenograft tumor model was also used to estimate the effect of circ_ASAP2 on tumor growth in vivo. Results: The expression levels of circ_ASAP2 and CDK6 were increased, and miR-770-5p level was decreased in GC tissues and cells. Furthermore, circ_ASAP2 knockdown inhibited cell viability, migration, and invasion of GC cells. Mechanically, circ_ASAP2 functioned as a sponge of miR-770-5p to regulate CDK6 expression, thereby boosting the progression of GC cells. Circ_ASAP2 silencing hindered the tumor growth of GC in vivo. Conclusion: Circ_ASAP2 knockdown can repress the development of GC cells partly through regulating the miR-770-5p/CDK6 axis, suggesting an underlying circRNA-targeted therapy for GC treatment.     

Candidate pathways and genes for nasopharyngeal carcinoma based on bioinformatics study

Purpose: To reveal the potential microRNAs (miRNAs), genes, pathways and regulatory network involved in the process of nasopharyngeal carcinoma (NPC) by using the method of bioinformatics. Methods: Gene expression profiles {"type":"entrez-geo","attrs":{"text":"GSE12452","term_id":"12452"}}GSE12452 (31 NPC and 10 normal samples) and {"type":"entrez-geo","attrs":{"text":"GSE53819","term_id":"53819"}}GSE53819 (18 NPC and 18 normal samples), as well as miRNA expression profiles {"type":"entrez-geo","attrs":{"text":"GSE32960","term_id":"32960"}}GSE32960 (312 NPC and 18 normal samples) and {"type":"entrez-geo","attrs":{"text":"GSE36682","term_id":"36682"}}GSE36682 (62 NPC and 6 normal samples) were obtained from Gene Expression Omnibus database. The differentially expressed genes (DEGs) and miRNAs (DEmiRNAs) between NPC and normal samples were identified by using t-test based on MATLAB software (FDR < 0.01), followed by pathway enrichment analysis based on DAVID software (P-value < 0.1). Then, DEmiRNA-DEG regulatory network was constructed. Results: A total of 1254 DEGs and 107 DEmiRNAs were identified, respectively. Then, 16 pathways (including cell cycle) and 32 pathways (including pathways in cancer) were enriched by DEGs and target genes of DEmiRNAs, respectively. Furthermore, DEmiRNA-DEG regulatory network was constructed, containing 12 DEmiRNAs (including has-miR-615-3P) and 180 DEGs (including MCM4 and CCNE2). Conclusion: has-miR-615-3p might take part in the pathogenetic process of NPC through regulating MCM4 which is enriched in cell cycle. The DEmiRNAs identified in the present study might serve as new biomarkers for NPC.     

Microarray-based measurement of microRNA-449c-5p levels in hepatocellular carcinoma and bioinformatic analysis of potential signaling pathways

The clinical role and potential molecular mechanisms of microRNA-449c-5p (miR-449c-5p) in hepatocellular carcinoma (HCC) tissues remains unclear. Combining multiple bioinformatic tools, we studied the miR-449c-5p expression levels in HCC tissues and explored possible target genes and related signaling pathways. First, miR-449c-5p expression data from microarrays provided by publicly available sources were mined and analyzed using various meta-analysis methods. Next, genes that were downregulated after miR-449c-5p mimic transfection into HCC cells were identified, and in silico methods were used to predict potential target genes. Several bioinformatic assessments were also performed to evaluate the possible signaling pathways of miR-449c-5p in HCC. Five microarrays were included in the current study, including GSE98269, GSE64632, GSE74618, GSE40744 and GSE57555. The standard mean difference was 0.44 (0.07–0.80), and the area under the curve was 0.68 (0.63–0.72), as assessed by meta-analyses, which consistently indicated the upregulation of miR-449c-5p in HCC tissues. A total of 2244 genes were downregulated after miR-449c-5p mimic transfection into an HCC cell line, while 5217 target genes were predicted by in silico methods. The overlap of these two gene pools led to a final group of 428 potential target genes of miR-449c-5p. These 428 potential target genes were primarily enriched in the homologous recombination pathway, which includes DNA Polymerase Delta 3 (POLD3). Data mining with Oncomine and the Human Protein Atlas showed a decreasing trend in POLD3 mRNA and protein levels in HCC tissue samples. This evidence suggests that miR-449c-5p could play an essential role in HCC through various pathways and that POLD3 could be a potential miR-449c-5p target. However, these in silico findings should be validated with further experiments.     

Upregulation of microRNA-23a/b promotes tumor progression and confers poor prognosis in patients with gastric cancer

Background and purpose: To investigate the clinical significance of microRNA (miR)-23a and miR-23b expression in human gastric cancer (GC). Methods: Quantitative RT-PCR was performed to detect the expression changes of miR-23a and miR-23b in 160 human GC tissues and paired normal mucosa. The associations between miR-23a and miR-23b expression, and the selected clinicopathological characteristics and patients’ prognosis were also evaluated. Results: MiR-23a (GC vs. Normal: 3.98 ± 1.23 vs. 2.29 ± 1.12, P < 0.001) and miR-23b (GC vs. Normal: 3.70 ± 1.24 vs. 1.58 ± 1.18, P < 0.001) expression were both increased dramatically when compared with paired normal mucosa. Notably, the expression levels of miR-23a in GC tissues were positively correlated with those of miR-23b (Spearman correlation coefficient r = 0.77, P < 0.001). Then, the coexpression of miR-23a and miR-23b (miR-23a-high/miR-23b-high) in GC tissues was significantly associated with the advanced TNM stage (P < 0.001), the presence of lymph node metastasis (P = 0.008) and the great depth of invasion (P = 0.02). Furthermore, both univariate and multivariate analyses showed that miR-23a/miR-23b co-expression was an independent predictor for unfavorable overall survival. Conclusions: These results suggest that the dysregulation of miR-23a and miR-23b may be implicated in the progression of human GC. Combined expression of miR-23a and miR-23b appears to be a valuable marker for prognosis of this disease.     

Altered microRNA Expression Profiles of Extracellular Vesicles in Nasal Mucus From Patients With Allergic Rhinitis

Purpose

Allergic rhinitis (AR) is an inflammatory disorder of the upper airway. Exosomes or extracellular vesicles are nanosized vesicles of endosomal origin released from inflammatory and epithelial cells that have been implicated in allergic diseases. In this study, we characterized the microRNA (miRNA) content of exosomes in AR.

Methods

Extracellular vesicles were isolated from nasal mucus from healthy control subjects (n=10) and patients with severe AR (n=10). Vesicle RNA was analyzed by using a TaqMan microRNA assays Human Panel-Early Access kit (Applied Biosystems, Foster City, CA, USA) containing probes for 366 human miRNAs, and selected findings were validated with quantitative RT-PCR. Target prediction and pathway analysis for the differentially expressed miRNAs were performed using DIANA-mirPath.

Results

Twenty-one vesicle miRNAs were up-regulated and 14 miRNAs were under-regulated significantly (P<0.05) in nasal mucus from AR patients when compared to healthy controls. Bioinformatic analysis by DIANA-mirPath demonstrated that 32 KEGG biological processes were significantly enriched (P<0.05, FDR corrected) among differentially expressed vesicle miRNA signatures. Among them, the B-cell receptor signaling pathway (P=3.709E-09), the natural killer cell-mediated cytotoxicity (P=8.466E-05), the T-cell receptor signaling pathway (P=0.00075), the RIG-I-like receptor signaling pathway (P=0.00127), the Wnt signaling pathway (P=0.00130), endocytosis (P=0.00440), and salivary secretion (P=0.04660) were the most prominent pathways enriched in quantiles with differential vesicle miRNA patterns. Furthermore, miR-30-5p, miR-199b-3p, miR-874, miR-28-3p, miR-203, and miR-875-5p, involved in B-cell receptor and salivary secretion signaling pathways, were selected for validation using independent samples from 44 AR patients and 20 healthy controls. MiR-30-5p and miR-199b-3p were significantly increased in extracellular vesicles from nasal mucus when compared to healthy controls, while miR-874 and miR-28-3p were significantly down-regulated. In addition, miRNA-203 was significantly increased in AR patients, while miRNA-875-5p was found to be significantly decreased in AR patients.

Conclusions

This study demonstrated that vesicle miRNA may be a regulator for the development of AR.     

MicroRNA-29 mediates TGFβ1-induced extracellular matrix synthesis by targeting wnt/β-catenin pathway in human orbital fibroblasts

Purpose: Transforming growth factor β1 (TGFβ1) is very important in the synthesis and degradation of extracellular matrix (ECM) and also in the mediation of human orbital fibroblasts (OFs) proliferation. MicroRNA-29 (MiR-29) plays an important role in this process. In the present study, the effects of TGFβ1 on the expression of miR-29 and whether miR-29 is involved in pro-survival signaling pathways mediated by TGFβ1 were examined in human OFs. Methods: Detecting the influence of TGFβ1 on the expression of miR-29a/b/c by real-time PCR analysis. Using 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) to detecting the influence of miR-29 on the increased proliferation caused by TGF-β1 on the human orbital fibroblasts. Using soft agar assay to detecting the influence of miR-29 on the increased colony formation caused by TGF-β1 on the human orbital fibroblasts. Western blot was used to detect the specific mechanisin. Results: TGFβ1 treatment decreases the expression of miR-29 in OFs. In the cultured OFs, the value of optical density (OD) in the group treated with miR-29 is lower than that in the group treated without miR-29 (P < 0.05). In the cultured OFs, the ratio of colony formation in the group treated with miR-29 is lower than that in the group treated without miR-29 (P < 0.05). In OFs, miR-29 decreases the secretion of Wnt3a and activation of β-catenin whether the treatment of TGFβ1 was used or not. MiR-29 decreases expression of Collagen, type I, alpha 1 (COL1A1) through down-regulation of wnt/β-catenin pathway. Conclusions: In OFs TGFβ1 treatment decreases expression of miR-29 which can cause the inhibition of normal ability of TGFβ1. MiR-29 inhibits TGFβ1-induced proliferation of OFS cell and decreases colony formation of OFS cell after TGFβ1 treatment. MiR-29 Mediates TGFβ1-induced Extracellular matrix synthesis through activation of Wnt/β-catenin pathway in human OFs.     

Identification and validation of redox-immune based prognostic signature for hepatocellular carcinoma

The intimate interaction between redox signaling and immunity has been widely revealed. However, the clinical application of relevant therapeutic is unavailable due to the absence of validated markers that stratify patients. Here, we identified novel biomarkers for prognosis prediction in hepatocellular carcinoma (HCC). Prognostic redox-immune-related genes for predicting overall survival (OS) of HCC were identified using datasets from TCGA, LIRI-JP, and {"type":"entrez-geo","attrs":{"text":"GSE14520","term_id":"14520"}}GSE14520. LASSO Cox regression was employed to construct the signature model and generate a risk score in the TCGA cohort. The signature contained CDO1, G6PD, LDHA, GPD1L, PPARG, FABP4, CCL20, SPP1, RORC, HDAC1, STC2, HDGF, EPO, and IL18RAP. Patients in the high-risk group had a poor prognosis compared to the low-risk group. Univariate and multivariate Cox regressions identified this signature as an independent factor for predicting OS. Nomogram constructed by multiple clinical parameters showed good performance for predicting OS indicated by the c-index, the calibration curve, and AUC. GSEA showed that oxidoreductase activity and peroxisome-related metabolic pathways were enriched in the low-risk group, while glycolysis activity and hypoxia were higher in the high-risk group. Furthermore, immune profiles analysis showed that the immune score and stromal score were significantly decreased in the high-risk group in the TCGA cohort. There was a considerably lower infiltration of anti-tumor immune cells while a higher proportion of pro-tumor immune cells in silico. Immune markers were distinctly expressed between the subgroups, and redox-sensitive immunoregulatory biomarkers were at higher levels in the high-risk group. Altogether, we identified a redox-immune prognostic signature. A more severe redox perturbation-driven immunosuppressive environment in the high-risk group stratified by the signature may account for poor survival. This may provide a clue to the combined therapy targeting redox and immune in HCC.     

MicroRNA-200a inhibits epithelial-mesenchymal transition in human hepatocellular carcinoma cell line

Objective: Our study investigated the role of microRNA (miR)-200a and its molecular targets in hepatocellular carcinoma (HCC) cells. Methods: An inhibitor of miR-200a was transiently transfected into the hepatocellular carcinoma cell line, MHCC-97L. The effect of this transfection on mRNA levels of epithelial-mesenchymal transition (EMT)-related genes was measured by fluorescence-based quantitative real-time polymerase chain reaction (qRT-PCR). Further, protein levels of EMT-related genes, cell proliferation and apoptosis-related markers were assessed by Western blot analysis in these transfected cells. MTT and wound-healing assay were used to evaluate the proliferation and migration of MHCC-97L cells in presence and in absence of miR-200a inhibitor. Results: Compared with miR-NC control group, qRT-PCR results in anti-miR-200a group revealed a significant reduction in the mRNA levels of E-cadherin, with a concomitant increasing in vimentin mRNA level (all P < 0.05). Western blot results showed higher E-cadherin and Caspase-3 protein expressions in anti-miR-200a group compared to miR-NC group (P < 0.05). In addition, vimentin and Ki-67 protein expression was found sharply decreased in anti-miR-200a group compared to miR-NC group (P < 0.05). Consistent with this, wound-healing and MTT assay showed that migration and proliferation capacity of MHCC-97L cells in anti-miR-200a group is significantly increased compared with miR-NC group (both P < 0.05). Conclusion: Our study reveals an important role of miR-200a in inhibiting EMT, proliferation and migration in HCC cells, suggesting the possibility of miR-200a-based therapeutics in HCC.     

Manifestations of type 2 diabetes in corneal endothelial cell density,corneal thickness and intraocular pressure

We sought to evaluate central corneal thickness (CCT), corneal endothelial cell density (ECD) and intraocular pressure (IOP) in patients with type 2 diabetes mellitus (DM) and to associate potential differences with diabetes duration and treatment modality in a prospective, randomized study. We measured ECD, CCT and IOP of 125 patients with type 2 DM (mean age 57.1±11.5 years) and compared them with 90 age-matched controls. Measured parameters were analyzed for association with diabetes duration and glucose control modalities (insulin injection or oral medication) while controlling for age. In the diabetic group, the mean ECD (2511±252 cells/mm²), mean CCT (539.7±33.6 µm) and mean IOP (18.3±2.5 mmHg) varied significantly from those the control group [ECD: 2713±132 cells/mm² (P<0.0001), CCT: 525.0±45.3 µm (P=0.003) and IOP: 16.7±1.8 mmHg (P<0.0001)]. ECD was significantly reduced by about 32 cell/mm² for diabetics with duration of >10 years when compared with those with duration of <10 years (P<0.05). CCT was thicker and IOP was higher for diabetics with duration of >10 years than those with duration of <10 years (P>0.05). None of the measured parameters was significantly associated with diabetes duration and treatment modality (P>0.05). In conclusion, subjects with type 2 DM exhibit significant changes in ECD, IOP and CCT, which, however, are not correlated with disease duration or if the patients receive on insulin injection or oral medications.     

Bioinformatics Analyses of Potential miRNA-mRNA Regulatory Axis in HBV-related Hepatocellular Carcinoma

Aims: We aimed to explore the crucial miRNA-mRNA axis through bioinformatics analysis and provide evidences for the development of pathophysiological mechanisms and new therapies for HBV-related HCC.Methods: MiRNA ({"type":"entrez-geo","attrs":{"text":"GSE76903","term_id":"76903"}}GSE76903) and mRNA ({"type":"entrez-geo","attrs":{"text":"GSE77509","term_id":"77509"}}GSE77509) dataset were used to screen differentially expressed miRNAs (DE-miRNAs) and differentially expressed mRNAs (DE-mRNAs) using R software. Overlapping genes between DE-mRNAs and target genes of DE-miRNAs were identified as candidate genes. Hub genes were obtained via cytohubba analysis. The expression at protein and mRNA levels and prognostic value of hub genes were evaluated based on The Cancer Genome Atlas (TCGA) data. Key miRNA-mRNA axes were constructed according to predicted miRNA-mRNA pairs. MiRNA expression and prognostic role were respectively identified using starBase v3.0 and Kaplan-Meier plotter database. Real-time PCR was performed to verify the expression of crucial miRNAs and mRNAs. Coexpression of crucial miRNA and mRNA were analyzed using starBase v3.0.Results: CDK1, CCNB1, CKS2 and CCNE1 were screened as hub genes, which were significantly upregulated at protein and mRNA levels. These up-regulated hub genes were also significantly associated with poor prognosis. Hsa-mir-195-5p/CDK1, hsa-mir-5589-3p/CCNB1 and hsa-let-7c-3p/CKS2 were screened as critical miRNA-mRNA axes. Critical miRNAs were decreased in HCC, which indicates unfavourable prognosis. QPCR results showed that crucial miRNAs were decreased, whereas critical mRNAs were increased in HBV-related HCC. A reverse relationship between miRNA and mRNA in crucial axis was further verified.Conclusion: This study identified several miRNA-mRNA axes in HBV-related HCC. Hsa-mir-195-5p/CDK1, hsa-mir-5589-3p/CCNB1 and hsa-let-7c-3p/CKS2 might serve as potential prognostic biomarkers and therapeutic targets for HBV-related HCC.     

JMJD5 is a potential oncogene for colon carcinogenesis

Objective: To observe the effects of Jumonji C domain-containing (JMJD) 5 depletion on colon cancer (CC). Methods: A short-hairpin RNA targeting JMJD5 was transfected into a lentivirus to make Lv-shJMJD5 for infection into the Caco-2 human cell. Besides, a negative control shRNA was constructed. The mRNA and protein levels of JMJD5 were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting, respectively. Cell proliferation, migration, and invasion were assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), soft agar colony assay and transwell assay, respectively. In addition, immunohistochemical (IHC) staining was performed to investigate the expression of JMJD5 in adjacent normal tissues and tumor tissues from patients with CC. Results: Compared with control group, mRNA and protein levels of JMJD5 was significantly reduced after infection with Lv-shJMJD5 (P<0.05), and Caco-2 cell proliferation, migration, and invasion were all obviously inhibited (P<0.05). The results of IHC showed that JMJD5 was significantly up-regulated compared with normal tissues (P<0.01). Additionally, follow-up data demonstrated that the survival rate of patients with high expression of JMJD5 was obviously lower than that with low expression (P<0.01). Conclusions: JMJD5 depletion could significantly inhibit human CC cell proliferation, migration, and invasion, implying that JMJD5 might be a potential oncogene.     

miR-126 regulated breast cancer cell invasion by targeting ADAM9

Accumulating evidence has shown that microRNAs (miRNAs) deregulation is commonly observed in human malignancies and crucial to cancer metastasis. Herein, we demonstrated that miR-126 play a suppressor role in human breast cancer cells invasion through the direct repression of a disintegrin and metalloprotease 9 (ADAM9). MiR-126 expression was investigated in forty cases of breast cancer specimens by real-time PCR. Transwell assay was conducted to explore the effects of miR-126 on the invasion of human breast cancer cell lines. The impact of miR-126 overexpression on putative target ADAM9 was subsequently confirmed by Western blot analysis. Our results indicated that miR-126 expression was frequently down-regulated in breast cancer specimens compared with adjacent normal tissues (P<0.05). Overexpression of miR-126 significantly reduced (P<0.05) the protein levels of ADAM9, further suppressed (P<0.05) breast cancer cell invasion in vitro. Meanwhile, knockdown of ADAM9 by small interfering RNA (siRNA) also inhibited (P<0.05) breast cancer cell invasion. Thus, our study revealed that miR-126 may act as a tumor suppressor via inhibition of cell invasion by downregulating ADAM9 in breast cancer development.     

Role of miR-101 in pheochromocytoma patients with SDHD mutation

This study aimed to screen the potential diagnostic biomarkers for distinguishing the malignant pheochromocytoma (PCC) from benign PCC. A total of 59 patients with PCC (benign and malignant) were enrolled in this study. The expression level of miRNAs in patients with different kind PCCs (healthy control, benign, malignant, malignant with or without SDHD mutation, adrenal and extra-adrenal) was analyzed using the qRT-PCR analysis. Besides, the diagnosis accuracy of miRNA in PCC samples was analyzed using the ROC analysis. Moreover, level of miR-101 in serum was detected by qRT-PCR analysis and serum VEGF level in patients with PCC was detected using the ELISA kit. Compared with benign PCC, miR-101 level was higher in patients with malignant PCC (P < 0.05), while the level of miR-513-5p and miR-26b showed no difference between malignant PCC and benign PCC (P > 0.05). miR-101 expression was significantly increased in malignant tumor tissue with SDHD mutation (P < 0.05) and in extra-adrenal tissues (P < 0.05), respectively. Besides, AUCs for miR-101 in PCC samples was 0.79 and for which in PCC samples with non-SDHD mutation was 0.77. Besides, serum miR-101 in malignant PCC was high but showed no difference among groups (P > 0.05). Moreover, serum VEGF level in malignant tumors was significantly high compared with benign tumor, as well as that in malignant PCC with SDHD mutation (P < 0.05). Our study suggested that SDHD mutation may enhance the overexpression of miR-101 in malignant tumors and miR-101 may be a potential diagnostic biomarker for malignant PCC and benign PCC.