Congying Xie

Profiling and bioinformatics analyses reveal differential circular RNA expression in radioresistant esophageal cancer cells

BackgroundAcquired radioresistance during radiotherapy is considered as the most important reason for local tumor recurrence or treatment failure. Circular RNAs (circRNAs) have recently been identified as microRNA sponges and involve in various biological processes. The purpose of this study is to investigate the role of circRNAs in the radioresistance of esophageal cancer.MethodsTotal RNA was isolated from human parental cell line KYSE-150 and self-established radioresistant esophageal cancer cell line KYSE-150R, and hybridized to Arraystar Human circRNA Array. Quantitative real-time PCR was used to confirm the circRNA expression profiles obtained from the microarray data. Bioinformatic tools including gene ontology (GO) analysis, KEGG pathway analysis and network analysis were done for further assessment.ResultsAmong the detected candidate 3752 circRNA genes, significant upregulation of 57 circRNAs and downregulation of 17 circRNAs in human radioresistant esophageal cancer cell line KYSE-150R were observed compared with the parental cell line KYSE-150 (fold changexa0≥2.0 and Pxa0<xa00.05). There were 9 out of these candidate circRNAs were validated by real-time PCR. GO analysis revealed that numerous target genes, including most microRNAs were involved in the biological processes. There were more than 400 target genes enrichment on Wnt signaling pathway. CircRNA_001059 and circRNA_000167 were the two largest nodes in circRNA/microRNA co-expression network.ConclusionsOur study revealed a comprehensive expression and functional profile of differentially expressed circRNAs in radioresistant esophageal cancer cells, indicating possible involvement of these dysregulated circRNAs in the development of radiation resistance.

Evaluation of Tumor-Derived Exosomal miRNA as Potential Diagnostic Biomarkers for Early-Stage Non-Small Cell Lung Cancer Using Next-Generation Sequencing.

Purpose: To identify tumor-derived exosomal biomarkers that are able to discriminate between adenocarcinoma and squamous cell carcinoma (SCC) as a noninvasive method in the early diagnosis of non–small cell lung cancer (NSCLC). Experimental Design: Tumor-derived exosomes from the plasma of early-stage NSCLC patients were isolated. Exosomal miRNA profiling of 46 stage I NSCLC patients and 42 healthy individuals was performed using miRNA-seq to identify and validate adenocarcinoma- and SCC-specific miRNAs. The diagnostic accuracy of select miRNAs was tested further with an additional 60 individuals. Results: There were 11 and 6 miRNAs expressed at remarkably higher levels, 13 and 8 miRNAs expressed at lower levels in adenocarcinoma and SCC patients, respectively, compared with healthy volunteers. Distinct adenocarcinoma- and SCC-specific exosomal miRNAs were validated. The reliability of miRNA-seq data was verified with several demonstrated diagnostic potential miRNAs for NSCLC and other carcinomas, as reported in previous studies, such as let-7, miR-21, miR-24, and miR-486. The results indicated that miR-181-5p, miR-30a-3p, miR-30e-3p, and miR-361-5p were adenocarcinoma-specific, and miR-10b-5p, miR-15b-5p, and miR-320b were SCC-specific. The diagnostic accuracy of three combination miRNA panels was evaluated using an AUC value of 0.899, 0.936, and 0.911 for detecting NSCLC, adenocarcinoma, and SCC, respectively. Conclusions: Tumor-derived exosomal miRNAs, adenocarcinoma-specific miR-181-5p, miR-30a-3p, miR-30e-3p and miR-361-5p, and SCC-specific miR-10b-5p, miR-15b-5p, and miR-320b were observed by next-generation sequencing, and their diagnostic accuracy were verified. These miRNAs may be promising and effective candidates in the development of highly sensitive, noninvasive biomarkers for early NSCLC diagnosis. Clin Cancer Res; 23(17); 5311–9. ©2017 AACR.

Identification of microRNAs involved in the radioresistance of esophageal cancer cells.

Radioresistance is considered as the most important reason for local tumour recurrence. This study investigates the role of miRNAs in radioresistant human esophageal cancer cells. Human miRNA microarray has been used to detect the differential expressed microRNAs between radioresistant esophageal cell line KYSE‐150R and the parental cell line KYSE‐150. The relative expression of some candidate miRNAs was measured by quantitative real‐time PCR (qRT‐PCR). Potential mRNA targets were analysed bioinformatically. Significant upregulation of 10 microRNAs and downregulation of 25 microRNAs were detected. The statistical significance of downregulation in hsa‐miR‐301a, hsa‐miR‐141 and hsa‐miR‐18b expression (Pu2009<u20090.05) were confirmed by qRT‐PCR. The correlation of the predicted microRNA target genes to apoptosis (63 genes), cell cycle (67 genes), DNA damage and repair (18 genes) were confirmed by functional annotation. The downregulation of hsa‐miR‐301a promoted radioresistance in KYSE‐150R through the upregulation of wnt1, indicating that wnt/β‐catenin signal pathway might be important in radioresistance. In conclusion, a unique set of miRNAs and their expression profiles in radiation resistance have been identified, providing a solid basis for future studies to investigate the target genes of these miRNAs and their function.

Down-regulation of Dicer expression in cervical cancer tissues.

Dicer is a component of the MicroRNA-producing machinery. The altered expression of Dicer may play a role in oncogenesis. The purpose of this study was to evaluate the expression of Dicer in cervical cancer tissues and its significance. Cancer tissues, para-cancer tissues and corresponding normal tissues were obtained from 31 cervical cancer patients undergoing surgery. Expression levels of Dicer mRNA were evaluated in these tissues using the real-time reverse transcription PCR. The association of the Dicer expression levels with clinical characteristics was also examined. The expression levels of Dicer mRNA were decreased in 66.7xa0% (18/27) and 76.9xa0% (20/26) of cervical cancer and para-cancer specimens, respectively, compared with corresponding normal tissues. The lower expression levels of Dicer in cancer tissues were associated with advanced tumor stages (pxa0=xa00.03) and with metastasis (pxa0=xa00.01). The down-regulation of Dicer expression in cancer and para-cancer tissues was observed. The lower expression of Dicer in cancer tissues demonstrated to be associated with tumor stages and metastasis. Future studies with a greater number of tissues to more conclusively determine the extent of low-level expression of Dicer in cervical cancer are warranted.

Increased p16 and p53 protein expression predicts poor prognosis in mucosal melanoma

Primary mucosal melanoma (MM) is a rare, and aggressive, neoplasm with a poor prognosis. To date, few prognostic markers of MM have been well-defined. The aim of this study is to clarify the prognostic value of p53 and p16 proteins in predicting the clinical outcome of Chinese patients with MM. A total of 59 MM samples were contained from biopsy specimens, and, expressions of p53 and p16 proteins were assessed by immunohistochemistry. Cox regression analysis was performed to investigate the association of these proteins with the overall survival of MM patients. Increased p16 expression was significantly associated with reduced survival at three years (P=0.039). Increased p53 expression correlates with reduced one-year (P=0.025), and, two-year survival (P=0.037). Increased p53 and p16 protein expression may be helpful prognostic indicators for the management of these patients.Primary mucosal melanoma (MM) is a rare, and aggressive, neoplasm with a poor prognosis. To date, few prognostic markers of MM have been well-defined. The aim of this study is to clarify the prognostic value of p53 and p16 proteins in predicting the clinical outcome of Chinese patients with MM.A total of 59 MM samples were contained from biopsy specimens, and, expressions of p53 and p16 proteins were assessed by immunohistochemistry. Cox regression analysis was performed to investigate the association of these proteins with the overall survival of MM patients. Increased p16 expression was significantly associated with reduced survival at three years (P=0.039). Increased p53 expression correlates with reduced one-year (P=0.025), and, two-year survival (P=0.037).Increased p53 and p16 protein expression may be helpful prognostic indicators for the management of these patients.

Adjuvant Therapeutic Modalities Following Three-field Lymph Node Dissection for Stage II/III Esophageal Squamous Cell Carcinoma

Background: The rates of locoregional and distant recurrence for esophageal squamous cell carcinoma (ESCC) patients underwent radical esophagectomy remain high. The purpose of this study is to explore an optimal postoperative therapeutic modality by investigating the efficacy of various adjuvant therapies in the treatment of ESCC. Methods: We retrospectively reviewed 408 ESCC patients underwent thoracic esophagectomy and 3-field lymph node dissection from 2010 to 2015. Patients were classified into surgery alone (Group S), adjuvant chemotherapy (Group CT) and postoperative chemotherapy plus radiotherapy (Group CRT), respectively. Univariate and multivariate Cox regression analyses were used to analyze prognostic factors and survival. Results: The overall survival (OS) and disease-free survival (DFS) were similar among groups. Postoperative CT and CRT both were beneficial for patients with positive lymph nodes, particularly for those with 3 or more lymph nodes involvement and metastasis in the middle thoracic segment compared with surgery alone. The 3-year OS and DFS for patients with 3 or more lymph nodes involvement were 30.8%, 53.7%, 50.5% and 19.9%, 41.6%, 34.0% for Group S, CT, and CRT, respectively (p=0.04; p=0.004, respectively). There was no notable difference in OS and DFS between the adjuvant Group CT and CRT (p=0.42; p=0.49, respectively). Postoperative CRT significantly reduced the rates of distant metastasis and overall recurrence for patients with positive lymph nodes (p=0.042; p=0.01, respectively). Number of metastatic lymph nodes, extent of resection, and AJCC stage were independent predictors of survival. Grade 1-2 myelosuppression was experienced significantly more frequently by patients in Group CRT than those in Group CT (P=0.03). Late toxicities were rare and manageable overall. Conclusions: Postoperative CT and CRT both were associated with better survival for patients with positive lymph nodes, particularly for those with 3 or more lymph nodes involvement and metastasis in the middle thoracic segment. Postoperative CRT was significantly more effective at reducing the rates of distant metastasis and overall recurrence for patients with positive lymph nodes.

The efficacy and roles of combining temozolomide with whole brain radiotherapy in protection neurocognitive function and improvement quality of life of non-small-cell lung cancer patients with brain metastases

BackgroundBrain metastasis (BM) is a poor prognostic factor for non-small-cell lung cancer (NSCLC). The efficacy and roles of combining temozolomide (TMZ) with whole brain radiotherapy (WBRT) in protection neurocognitive function (NCF) and improvement quality of life (QOL) were investigated and compared with WBRT alone in the treatment of NSCLC patients with BM.MethodsA total of 238 NSCLC patients with BM were reviewed and categorized into WBRT plus TMZ (RCT) arm and WBRT alone (RT), respectively. The efficacy was evaluated with Pearson chi-square or Fisher’s exact tests, Log-rank test and Cox proportional hazards model. NCF was assessed by using revised Hopkins Verbal Learning Test (HVLT-R), Controlled Oral Word Association (COWA) test and Trail-making Test (TMT). QOL was assessed by the Functional Assessment of Cancer Treatment-Lung (FACT-L) Chinese version 4.0 questionnaire.ResultsThe average intracranial objective response (ORR) and disease control rate (DCR) for all the patients were 26.9 and 95.8%, respectively. The intracranial ORR and DCR for RCT and RT arm were 34.9% vs. 20.2% (pu2009=u20090.01) and 98.4% vs. 92.7% (pu2009=u20090.03), respectively. The median intracranial progression-free survival (PFS) and overall survival (OS) of NSCLC patients with BM were 5.2 and 7.3xa0months, respectively. The median PFS of RCT arm was significantly longer than that of RT arm (5.9 vs. 4.9xa0months, pu2009=u20090.002). The median OS of the RCT arm was also slightly longer than that of the RT arm (8.5 vs. 5.9xa0months), but without statistical significance (pu2009=u20090.11). Multivariate analysis indicated that TMZ was a significant factor for PFS. Statistically significant differences on NCF and QOL were observed between CRT and RT arms at 5xa0months. RCT showed a trend of toxicities increase compared with RT, however, the toxicities were tolerable and manageable.ConclusionsAdding TMZ to WBRT in the treatment of NSCLC patients with BM could improve the intracranial ORR, DCR, and median PFS compared with WBRT alone. Although no remarkable difference on median OS was found, adding TMZ could prevent NCF and QOL from worsening. The side effects increased by adding TMZ, but the difference was not statistical significance and toxicities were well tolerated.

Inhibition of cyclin D1 enhances sensitivity to radiotherapy and reverses epithelial to mesenchymal transition for esophageal cancer cells

Acquired radioresistance during radiotherapy has significantly affected the treatment efficacy in esophageal cancer. Many of radioresistant cancer cells demonstrated epithelial-mesenchymal transition (EMT).We found in previous study that a radioresistant cell line (KYSE-150R) possessed EMT characteristic with cyclin D1 overexpression. Cyclin D1 has been demonstrated to affect the radiation sensitivity in cancer cells. To elucidate the molecular functions of cyclin D1 on EMT phenotypes and esophageal cancer radiosensitivity, we treated the radioresistant esophageal cancer cells (KYSE-150R) and parental cells (KYSE-150) with cyclin D1 small interfering RNA (siRNA). The cell proliferation rate of KYSE-150R and the radiation survival fraction were significantly decreased in cyclin D1 siRNA treatment group. Knocking down cyclin D1 resulted in G0/G1 arrest in KYSE-150R cells. The average number of irradiation-induced γ-H2AX foci increased in the cells treated with cyclin D1 siRNA, indicating impaired DNA double-strand break (DSB) repair in KYSE-150R cells. Cyclin D1 also reversed EMT phenotypes with significantly increased expression of E-cadherin in KYSE-150R cells. However, cyclin D1 siRNA have no radiosensitizing effects on KYSE-150 cells, with no obvious change in EMT marker expression .Our work showed that EMT phenotypes can be reduced and the radiosensitivity of esophageal cancer cells can be enhanced by inhibiting cyclin D1.

Efficacy of Second-line Tyrosine Kinase Inhibitors in the Treatment of Metastatic Advanced Non-small-cell Lung Cancer Harboring Exon 19 and 21 EGFR Mutations

Background: Although superior clinical benefits of first-line epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in the treatment of advanced non-small-cell lung cancer (NSCLC) had been reported with different sensitivity, the sensitivity of second-line TKIs in NSCLC patients with different EFGR mutations was unknown. The purpose of this study is to investigate the clinical outcome of second-line EGFR-TKIs in the treatment of NSCLC patients according to different EGFR genotypes. Methods: The treatment outcomes of 166 NSCLC patients with different EGFR mutations treated by second-line TKIs were retrospectively reviewed. The efficacy was evaluated with Pearson chi-square or Fishers exact tests, Log-rank test and Cox proportional hazards model. Results: The disease control rate (DCR) and objective response rate (ORR) of enrolled NSCLC patients were 77.7% and 11.4%, respectively. The exon 19 deletion group had a significantly longer median progression-free survival (PFS) (6.7 vs. 4.5 months, P=0.002) and overall survival (OS) (13.7 vs. 11.7 months, P=0.02) compared with the exon 19 L858R mutation group for NSCLC patients, as well for patients with brain metastasis [PFS: (6.7 vs. 3.9 months, p<0.001), OS: (13.7 vs. 7.9 months, p=0.006)]. No significant difference on PFS and OS was observed between exon 19 deletion and L858R mutation group for patients with bone metastasis. EGFR genotype and ECOG PS were independent predictors of PFS. Never smoking, exon 19 deletion, EGOC PS (0-1) and no brain metastasis were correlated with longer OS. No significant difference on side effect between exon 19 and 21 mutation group was observed. Conclusions: NSCLC patients harboring exon 19 deletion achieved better PFS and OS than those with L858R mutation, indicating that EGFR mutation is a significant prognostic factor for advanced NSCLC patients with and without brain metastasis receiving second-line EGFR-TKIs treatment.

Concurrent paclitaxel/cisplatin chemoradiotherapy with or without consolidation chemotherapy in high-risk early-stage cervical cancer patients following radical hysterectomy: preliminary results of a phase III randomized study

A phase III randomized study on the efficacy and safety of consolidation chemotherapy with paclitaxel plus cisplatin following radical hysterectomy and adjuvant chemoradiotherapy (CRT) in the treatment of high risk early-stage cervical cancer were reported. 146 eligible patients were randomized to arm A receiving concurrent CRT or arm B receiving CRT plus consolidation chemotherapy, respectively. An interim analysis showed a trend of improvement on disease-free survival (DFS) and overall survival (OS) in arm B with hazard ratios (HR) of 1.25 (95% CI = 0.60–2.60, p = 0.55) and 1.43 (95% CI = 0.64–3.20, p = 0.38) for DFS and OS, respectively. The 3-year DFS and OS were 82.0% vs.74.3%, and 86.6% vs. 78.3% for patients receiving CRT plus consolidation chemotherapy and CRT alone, respectively. There was significant difference between the two arms in distant alone recurrence (p = 0.048). Multivariate analysis indicated that pathologic type was a significant prognostic factor for OS (p = 0.045), positive pelvic nodes were significantly associated with both OS (p=0.02) and DFS (P=0.03). Grade 2 to 4 gastrointestinal disorder (p = 0.95), radiation enteritis (P=0.48), radiation cystitis (p = 0.27) and radioepidermitis (p = 0.46) were similar in the two arms. Overall rates of grade 0–2/3–4 myelosuppression were 87.7%/12.3% for arm A and 74.6%/25.4% for arm B, respectively, but this difference was not statistically significant (p = 0.05). In conclusion, concurrent CRT plus consolidation chemotherapy may play a potential role in further improving survival outcomes for high-risk early stage cervical cancer patients compared CRT alone.