MicroRNA-1275 induces radiosensitization in oesophageal cancer by regulating epithelial-to-mesenchymal transition via Wnt/ß-catenin pathway.

Acquired radioresistance is one of the main obstacles for the anti-tumour efficacy of radiotherapy in oesophageal cancer (EC). Recent studies have proposed microRNAs (miRNAs) as important participators in the development of radioresistance in various cancers. Here, we investigated the role of miR-1275 in acquired radioresistance and epithelial-mesenchymal transition (EMT) in EC. Firstly, a radioresistant cell line KYSE-150R was established, with an interesting discovery was observed that miR-1275 was down-regulated in KYSE-150R cells compared to the parental cells. Functionally, miR-1275 inhibition elevated radioresistance in KYSE-150 cells via promoting EMT, whereas enforced expression of miR-1275 increased radiosensitivity in KYSE-150R cells by inhibiting EMT. Mechanically, we demonstrated that miR-1275 directly targeted WNT1 and therefore inactivated Wnt/ß-catenin signalling pathway in EC cells. Furthermore, WNT1 depletion countervailed the promoting effect of miR-1275 suppression on KYSE-150 cell radioresistance through hampering EMT, whereas WNT1 overexpression rescued miR-1275 up-regulation-impaired EMT to reduce the sensitivity of KYSE-150R cells to radiation. Collectively, our findings suggested that miR-1275 suppressed EMT to encourage radiosensitivity in EC cells via targeting WNT1-activated Wnt/ß-catenin signalling, providing a new therapeutic outlet for overcoming radioresistance of patients with EC.

Ginsenoside Rg3 suppresses the growth of gemcitabine-resistant pancreatic cancer cells by upregulating lncRNA-CASC2 and activating PTEN signaling.

Pancreatic cancer is one of the most fatal malignancies with high mortality. Gemcitabine (GEM)-based chemotherapy is the most important treatment. However, the development of GEM resistance leads to chemotherapy failure. Previous studies demonstrated the anticancer activity of ginsenoside Rg3 in a variety of carcinomas through modulating multiple signaling pathways. In the present study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, colony formation assay, flow cytometry apoptosis assay, Western blotting assay, xenograft experiment, and immunohistochemistry assay were performed in GEM-resistant pancreatic cancer cell lines. Ginsenoside Rg3 inhibited the viability of GEM-resistant pancreatic cancer cells in a time-dependent and concentration-dependent manner through induction of apoptosis. The level of long noncoding RNA cancer susceptibility candidate 2 (CASC2) and PTEN expression was upregulated by the ginsenoside Rg3 treatment, and CASC2/PTEN signaling was involved in the ginsenoside Rg3-induced cell growth suppression and apoptosis in GEM-resistant pancreatic cancer cells. Ginsenoside Rg3 could be an effective anticancer agent for chemoresistant pancreatic cancer.

Polydatin inhibits proliferation and promotes apoptosis of doxorubicin-resistant osteosarcoma through LncRNA TUG1 mediated suppression of Akt signaling.

BACKGROUND: Development of doxorubicin-resistance is the main difficulty for osteosarcoma treatment. LncRNA Taurine upregulated gene 1 (TUG1) has been identified as oncogenic lncRNA in different types of carcinomas and was involved in chemoresistance. We aim to evaluate the anti-proliferative effects and the underlying molecular mechanism of Polydatin in doxorubicin-resistant osteosarcoma. METHODS: Doxorubicin-resistant osteosarcoma cell lines were established. MTT, colony formation, apoptosis assay, qRT-PCR and Western blotting analysis, immunohistochemistry and animal study were carried out. RESULTS: It has been showed Polydatin (50-250 µM) inhibited the cell proliferation in a dose- and time-dependent manner at 24 h, 48 h, and 72 h. Polydatin promoted the cell apoptosis significantly with the highest apoptosis rate >50%. Polydatin down-regulated TUG1 expression and TUG1/Akt signaling suppression was involved in Polydatin treated doxorubicin-resistant osteosarcoma cells. The in vivo study further confirmed the anti-cancer effect of Polydatin and related mechanisms. CONCLUSIONS: Polydatin may be a novel therapeutic agent for doxorubicin-resistant osteosarcoma treatment and TUG1 would be a potential molecular target.

Artesunate enhances radiosensitivity of esophageal cancer cells by inhibiting the repair of DNA damage.

Radiotherapy plays an important therapeutic role in esophageal cancer (EC). However, acquired radioresistance impairs the efficacy of radiotherapy, often leading to treatment failure. Therefore, it is important to develop novel radiosensitizers to enhance the clinical treatment of EC. The purpose of this study was to investigate the role of artesunate (ART) on radiosensitivity of human EC cell line TE-1. We found that ART inhibited the proliferation of EC cells and enhanced the radiosensitivity of TE-1 cells (SER = 1.24). In vivo tumor growth of xenografts was inhibited markedly by irradiation (IR) combined with ART, with a tumor inhibition rate of 53.76% in IR + ART group vs. 41.13% in IR-alone group. Pretreatment with ART significantly prompted cell apoptosis and reversed the IR-induced G2/M arrest. ART treatment could aggravate DNA damage of EC cells and prolong the formation of γ-H2AX foci induced by IR. ART up-regulated P21 and down-regulated the expression of cyclin D1, RAD51, RAD54, Ku70 and Ku86 protein of irradiated TE-1 cells. These findings support that ART induce radiosensitivity of TE-1 cells in vitro and in vivo, and may prove to be a promising radiosensitizer for EC treatment.

Treatment outcome comparisons between exons 19 and 21 EGFR mutations for non-small-cell lung cancer patients with malignant pleural effusion after first-line and second-line tyrosine kinase inhibitors.

Recent studies demonstrated a significantly increased frequency of epidermal growth factor receptor (EGFR) gene mutations in non-small cell lung cancer (NSCLC) patients with malignant pleural effusions (MPEs). The purpose of this study is to investigate the effect of first-line and second-line EGFR-tyrosine kinase inhibitors (TKIs) in the treatment of NSCLC with MPEs harboring exon 19 deletion and L858R mutation. From 2010 to 2015, 203 NSCLC patients with MPEs harboring EGFR mutation treated with EGFR-TKIs were reviewed. The efficacy were evaluated with Pearson chi-square or Fisher's exact tests, Log-rank test and Cox proportional hazards model. The objective response rate (ORR) and disease control rate (DCR) for patients treated with first-line and second-line EGFR-TKIs were 21.9%, 91.4% and 14.7%, 85.3%, respectively. The overall median PFS and OS of enrolled NSCLC patients with MPE were 9.3 months (95% CI, 8.4-10.2 months), 20.9 months (95% CI, 18.9-22.9 months) after first-line TKIs, and 7.6 months (95% CI, 6.6-8.6 months), 15.3 months (95% CI, 13.6-15.9 months) after second-line TKIs. The exon 19 deletion arm had a longer median PFS (9.4 vs 7.1 months, p=0.003) and OS (16.8 vs 13.8 months, p=0.003) compared with the L858R mutation arm after second-line TKIs. In a conclusion, EGFR genotype was an independent predictor of PFS and OS. No significant side effects differences between the two mutation groups was observed for first or second-line EGFR-TKIs. This study demonstrated that EGFR mutations are significant predictors for advanced NSCLC patients with MPE receiving second-line EGFR-TKIs treatment.

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.

BACKGROUND: Brain 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. METHODS: A 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. RESULTS: The 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% (p = 0.01) and 98.4% vs. 92.7% (p = 0.03), respectively. The median intracranial progression-free survival (PFS) and overall survival (OS) of NSCLC patients with BM were 5.2 and 7.3 months, respectively. The median PFS of RCT arm was significantly longer than that of RT arm (5.9 vs. 4.9 months, p = 0.002). The median OS of the RCT arm was also slightly longer than that of the RT arm (8.5 vs. 5.9 months), but without statistical significance (p = 0.11). 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 5 months. RCT showed a trend of toxicities increase compared with RT, however, the toxicities were tolerable and manageable. CONCLUSIONS: Adding 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.

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

BACKGROUND: Acquired 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. METHODS: Total 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. RESULTS: Among 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 change ≥2.0 and P < 0.05). 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. CONCLUSIONS: Our 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.

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.

Upregulated expression of long non-coding RNA LINC00982 regulates cell proliferation and its clinical relevance in patients with gastric cancer.

Emerging evidences indicate that dysregulated long non-coding RNAs (lncRNAs) are implicated in cancer tumorigenesis and progression and might be used as diagnosis and prognosis biomarker or potential therapeutic targets. Therefore, identification of cancer-associated lncRNAs and investigation of their biological functions and molecular mechanisms are important for understanding the development and progression of cancer. In this study, we identified a novel lncRNA LINC00982, whose expression was downregulated in tumor tissues in 106 patients with gastric cancer (GC) compared with those in the adjacent normal tissues (P < 0.001). Furthermore, decreased LINC00982 expression was negatively correlated with invasion depth (P < 0.001), advanced TNM stage (P = 0.004), and regional lymph node metastasis (P = 0.005). LINC00982 levels were robust in differentiating gastric cancer tissues from controls [area under the curve (AUC) = 0.742; 95 % confidence interval (CI) = 0.678-0.800, P < 0.01]. Kaplan-Meier analysis demonstrated that decreased LINC00982 expression contributed to poor overall survival (P < 0.01) and disease-free survival (P < 0.01) of patients. A multivariate survival analysis also indicated that LINC00982 could be an independent prognostic marker. The levels of LINC00982 in gastric juice from gastric patients were significantly lower than those from normal subjects (P = 0.026). Furthermore, knockdown of LINC00982 expression by small interfering RNA (siRNA) could promote cell proliferation and cell cycle progression, while ectopic expression of LINC00982 inhibited cell proliferation and rendered cell cycle arrest in GC cells partly via regulating P15 and P16 protein expressions. Our findings present that decreased lncRNA LINC00982 could be identified as a poor prognostic biomarker in GC and regulate cell proliferation.

Upregulated expression of long noncoding RNA SNHG15 promotes cell proliferation and invasion through regulates MMP2/MMP9 in patients with GC.

Accumulation of data indicates that misregulated long noncoding RNAs (lncRNAs) are implicated in cancer tumorigenesis and progression and might be served as diagnosis and prognosis biomarker or potential therapeutic targets. Identification of cancer-associated lncRNAs and investigation of their biological functions and molecular mechanisms are significant for understanding the development and progression of cancer. In this study, we identified a novel lncRNA SNHG15, whose expression was upregulated in tumor tissues in 106 patients with gastric cancer (GC) compared with those in the adjacent normal tissues (P < 0.001). Furthermore, increased SNHG15 expression was positively correlated with invasion depth (P < 0.001), advanced tumor node metastasis (TNM) stage (P = 0.001), and lymph node metastasis (P = 0.019). SNHG15 levels were robust in differentiating GC tissues from controls (area under the curve (AUC) = 0.722; 95 % confidence interval (CI) = 0.657-0.782, P < 0.01). Kaplan-Meier analysis demonstrated that elevated SNHG15 expression contributed to poor overall survival (P < 0.01) and disease-free survival (P < 0.01) of patients. A multivariate survival analysis also indicated that SNHG15 could be an independent prognostic marker. Furthermore, knockdown of SNHG15 expression by siRNA could inhibit cell proliferation and invasion and induce apoptosis, while ectopic expression of SNHG15 promoted cell proliferation and invasion in GC cells partly via regulating MMP2 and MMP9 protein expression. Our findings present that elevated lncRNA SNHG15 could be identified as a poor prognostic biomarker in GC and regulate cell invasion.

FH535 increases the radiosensitivity and reverses epithelial-to-mesenchymal transition of radioresistant esophageal cancer cell line KYSE-150R.

BACKGROUND: Acquired radioresistance has significantly compromised the efficacy of radiotherapy for esophageal cancer. The purpose of this study is to investigate the roles of epithelial-mesenchymal transition (EMT) and the Wnt/ß-catenin signaling pathway in the acquirement of radioresistance during the radiation treatment of esophageal cancer. METHODS: We previously established a radioresistant cell line (KYSE-150R) from the KYSE-150 cell line (a human cell line model for esophageal squamous cell carcinoma) with a gradient cumulative irradiation dose. In this study, the expression of EMT phenotypes and the Wnt/ß-catenin signaling pathway proteins were examined by real-time PCR, western blot and immunofluorescence in the KYSE-150R cells. The KYSE-150R cells were then treated with a ß-Catenin/Tcf inhibitor FH535. The expressions of nuclear and cytoplasmic ß-catenin and EMT markers in KYSE-150R cells were assessed at both mRNA and protein level after FH535 treatment. The radiosensitization effect of FH535 on KYSE-150R was evaluated by CCK8 analysis and a colony forming assay. DNA repair capacities was detected by the neutral comet assays. RESULTS: KYSE-150R cell line displayed obvious radiation resistance and had a stable genetic ability. EMT phenotype was presented in the KYSE-150R cells with decreased E-cadherin and increased snail and twist expressions. The up-regulated expressions of Wnt/ß-catenin signaling pathway proteins (Wnt1, FZD1-4, GSK3ß, CTNNB1 and Cyclin D1), the increased phosphorylation of GSK3ß, and the decreased phosphorylation of ß-catenin were observed in KYSE-150R cells compared with KYSE-150 cells, implicating the activation of the Wnt pathway in KYSE-150R cells. The expression of nuclear ß-catenin and nuclear translocation of ß-catenin from the cytoplasm was decreased after FH535 treatment. FH535 also reversed EMT phenotypes by increasing E-cadherin expression. The cell proliferation rates of KYSE-150R were dose-dependent and the radiation survival fraction was significantly decreased upon FH535 treatment. Neutral comet assays indicated that FH535 impairs DNA double stranded break repair in KYSE-150R cells. CONCLUSIONS: Acquisition of radioresistance and EMT in esophageal cancer cells is associated with the activation of the Wnt/ß-catenin pathway. EMT phenotypes can be reduced and the radiosensitivity of esophageal cancer cells can be enhanced by inhibiting the Wnt/ß-catenin pathway with FH535 treatment.

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 (P < 0.05) 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/ß-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.

Postoperative chemoradiotherapy for advanced gastric cancer after D2 gastrectomy.

BACKGROUND/AIMS: The purpose of this study is to investigate the role of postoperative chemoradiotherapy with paclitaxel and cisplatin in the multimodality treatment of locally advanced gastric cancer after D2 gastrectomy. METHODOLOGY: Sixty-five patients underwent D2 gastrectomy with stage IB-IV (M0) gastric cancers were enrolled. A postoperative radiotherapy dose of 46 Gy in 23 fractions with concurrent chemotherapy of paclitaxel and cisplatin were delivered to the patients. Chemotherapy was administrated with paclitaxel 135mg/ m2 at day 1 and 21, cisplantin 20mg/ m2 at day 1-3 and day 29-31 during the radiotherapy course. Sixty-three out off 65 eligible patients were irradiated to a total dose of 46Gy and completed two cycles of full-dose chemotherapy. Thirty-three patients died at the time of analysis. RESULTS: The median follow-up was 68.0 months (range 1.9-119.1). The 3-year overall survival (OS) and disease-free survival (DFS) were 78.5% and 73.2%, respectively. The 5-year OS and DFS were 57.4% and 54.8%, respectively. Toxicity was tolerant. The main toxicities were gastrointestinal disorder, hematologic toxicity and hair loss. CONCLUSION: This novel postoperative chemoradiotherapy regimen for patients with gastric cancer after D2 gastrectomy had a tolerable toxicity, however, it did not decrease the local recurrence rate.

CircRNA_101491 regulated the radiation sensitivity of esophageal squamous cell carcinomas via sponging miR-125a-5p.

BACKGROUND: At present, it has been found that many patients have acquired resistance to radiotherapy, which greatly reduces the effect of radiotherapy and further affects the prognosis. CircRNAs is involved in the regulation of radiosensitivity of many kinds of tumor cells. Therefore, the main purpose of this study is to explore the regulatory effect of CircRNA_101491 on radiosensitivity of ESCC and its related mechanism. METHODS: We established ESCC radiation-resistant cell line (KYSE150R cell) by gradient dose method, and tested the difference of KYSE150 between KYSE150R cell and parent cell in vitro. Then, after knocking down the expression of CircRNA_101491, a series of in vitro experiments were conducted to verify the effects of CircRNA_101491 on the phenotype and radiosensitivity of KYSE150R cells, and further analyzed the related regulatory mechanism. In addition, we also used the model of transplanted tumor in nude mice to investigate the effect of CircRNA_101491 on the radiosensitivity of ESCC in vivo. RESULTS: According to a series of in vitro experiments, we confirmed that KYSE150R cells lost the epithelial phenotype and obtained interstitial cell-like phenotype, and found that CircRNA_101491 was highly expressed in KYSE150R cells. In addition, we found that knocking down the expression of CircRNA_101491 will lift the inhibition of miR-125a-5p, and then reverse the process of EMT, accelerate the process of apoptosis, thus play a role in radiosensitization. The in vivo experiment of transplanted tumor in nude mice also showed that knocking down the expression of CircRNA_101491 could enhance the radiosensitivity of ESCC. CONCLUSION: In conclusion, we confirmed that interfering with the expression of CircRNA_101491 can relieve the inhibition of miR-125a-5p, thus reverse the process of interstitial phenotype, accelerate the process of apoptosis, and enhance the radiosensitivity of ESCC.

[Expression profiles of microRNAs in radioresistant esophageal cell line].

OBJECTIVE: To identify the differential microRNA expression profiles of acquired radioresistant esophageal cell line established by fractionated ionizing radiation (FIR) versus parental cell line. METHODS: MicroRNA microarray was employed for detection. Bioinformatic software tools were used to predict the target genes of identified microRNAs. For an understanding of miRNA functions, the GO analysis of abundantly differentially expressed targets of miRNAs was performed by GeneOntology Browser. RESULTS: Compared with parental cell line, 10 microRNAs (hsa-miR-1539, hsa-miR-1237, hsa-miR-92b, etc.) were up-regulated over 2-fold and 25 microRNAs (hsa-miR-185, hsa-miR-18b, hsa-miR-17, etc.) down-regulated in KYSE-150R. Eighteen miRNAs had their target genes, 10 of them had the potential to individually target up to 200 mRNAs. Hsa-let-7a, hsa-miR-185, hsa-miR-141, hsa-miR-92b, hsa-miR-22 and hsa-miR-301a were known as important genes associated with radioresistance. CONCLUSION: These results confirm the involvement of miRNA in radiation resistance. It may potentially help to explain the mechanisms of gene regulation in cellular response to radioresistance.

[Protein microarray analysis on changes in protein phosphorylation in recurrent nasopharyngeal carcinoma].

OBJECTIVE: To compare the differential phosphorylation level of proteins between relapsed nasopharyngeal carcinoma (rNPC) and primary nasopharyngeal carcinoma (pNPC). METHODS: Total protein was extracted from 4 pNPC tissue and 4 rNPC tissue samples from January 2003 to September 2005. Then it was analyzed by antibody microarray with 656 antibodies. The differential phosphorylation level of proteins was screened and clustering analysis conducted. The phosphorylation status of the protein sites and its functional pathways were analyzed via an online database of PhosphoSite Plus. The protein expressions were detected by immunohistochemistry. RESULTS: Relapsed and primary nasopharyngeal carcinomas had differential phosphorylation level of proteins. And 6 differentially expressed proteins were identified. The phosphorylation levels of KIT, ATP1A1, Synapsin, SEK1 and histone H2AX were up-regulated in rNPC (P = 0.007 - 0.048) while c-Jun was down-regulated (P = 0.030). The expression of P-H2AX in rNPC was significantly higher than that in pNPC [0.390 (0.175) vs 0.290 (0.155)], but p-c-Jun was significantly lower in rNPC than that in pNPC [0.625 (0.145) vs 0.725 (0.178)] (both P < 0.05). Among them, the changes in the phosphorylation levels of c-Jun, histone H2AX, SEK1 and KIT might play important roles in the relapse of NPC through improving DNA damage repair ability, inhibiting apoptosis and promoting tumorigenesis. CONCLUSION: The changes of protein phosphorylation may help to explain the recurrent mechanisms of NPC and provide new therapeutic anti-recurrence targets.

Infiltrating T-cell abundance combined with EMT-related gene expression as a prognostic factor of colon cancer.

EMT-related gene expression reportedly exhibits correlation with the anti-tumor immunity of T cells. In the present study, we explored the factors that might affect the efficacy of immunotherapy in colon cancer with treatment. In this regard, RNA-seq and clinical data of 469 colon cancer samples derived from the Cancer Genome Atlas (TCGA) database were used to calculate infiltrating T-cell abundance (ITA), to illustrate a pathway enrichment analysis, and to construct Cox proportional hazards (CPH) regression models. Subsequently, the RNA-seq and clinical data of 177 colon cancer samples derived from the GSE17536 cohort were used to validate the CPH regression models. We found that ITA showed correlation with EMT-related gene expression, and that it was not an independent prognostic factor for colon cancer. However, upon comparison of two groups with the same ITA, higher EMT expression helped predicted a worse prognosis, whereas a higher ITA could help predict a better prognosis upon comparison of two groups with the same EMT. Additionally, seven genes were found to be statistically related to the prognosis of patients with colon cancer. These results suggest that the balance between ITA and EMT-related gene expression is conducive to the prognosis of patients with colon cancer, and TPM1 is necessary to further explore the common target genes of immune checkpoint blockade.

Identification and Mechanism of the PD-1/PD-L1 Genomic Signature SORL1 as Protective Factor in Bladder Cancer.

Background: Immunotherapy has recently shown remarkable efficacy for advanced bladder cancer patients. Accordingly, identifying a biomarker associated with the programmed cell death protein 1 (PD-1)/its ligand (PD-L1) genomic signature to predict patient prognosis is necessary. Methods: In this study, we used mutation data and RNA-seq data of bladder cancer samples acquired from The Cancer Genome Atlas (TCGA) database to combine PD-1/PD-L1-associated mutational signatures with PD-1/PD-L1-associated differentially expressed genes (DEGs). Then, we performed a Kaplan-Meier analysis on the corresponding clinical data of the TCGA bladder urothelial carcinoma (BLCA) cohort to identify prognostic genes, and the results were validated using the GSE48075 cohort. The online platform UCSC Xena was used to analyze the relationship between the candidate genes and clinical parameters. We utilized the Human Protein Atlas (HPA) database to validate the protein expression levels. Then, correlation analysis, cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT) analysis, and gene set enrichment analysis (GSEA) were used to clarify the mechanism. Results: We identified one prognostic gene, sortilin related receptor 1 (SORL1), whose downregulation was associated with a comparatively advanced BLCA stage. While further exploring this finding, we found that SORL1 expression was negatively correlated with PD-1/PD-L1 expression and M2 macrophage levels. Furthermore, we found that the downregulation of SORL1 expression was significantly associated with a higher epithelial-mesenchymal transition (EMT) score. Conclusion: We described a novel PD-1/PD-L1-associated signature, SORL1, that predicts favorable outcomes in bladder cancer. SORL1 might reduce immune suppression and inhibit the M2 macrophage-induced EMT phenotype of tumor cells.

Immunological Classification of Pancreatic Carcinomas to Identify Immune Index and Provide a Strategy for Patient Stratification.

Background: Cancer immunotherapy has produced significant positive clinical effects in a variety of tumor types. However, pancreatic ductal adenocarcinoma (PDAC) is widely considered to be a "cold" cancer with poor immunogenicity. Our aim is to determine the detailed immune features of PDAC to seek new treatment strategies. Methods: The immune cell abundance of PDAC patients was evaluated with the single-sample gene set enrichment analysis (ssGSEA) using 119 immune gene signatures. Based on these data, patients were classified into different immune subtypes (ISs) according to immune gene signatures. We analyzed their response patterns to immunotherapy in the datasets, then established an immune index to reflect the different degrees of immune infiltration through linear discriminant analysis (LDA). Finally, potential prognostic markers associated with the immune index were identified based on weighted correlation network analysis (WGCNA) that was functionally validated in vitro. Results: Three ISs were identified in PDAC, of which IS3 had the best prognosis across all three cohorts. The different expressions of immune profiles among the three ISs indicated a distinct responsiveness to immunotherapies in PDAC subtypes. By calculating the immune index, we found that the IS3 represented higher immune infiltration, while IS1 represented lower immune infiltration. Among the investigated signatures, we identified ZNF185, FANCG, and CSTF2 as risk factors associated with immune index that could potentially facilitate diagnosis and could be therapeutic target markers in PDAC patients. Conclusions: Our findings identified immunologic subtypes of PDAC with distinct prognostic implications, which allowed us to establish an immune index to represent the immune infiltration in each subtype. These results show the importance of continuing investigation of immunotherapy and will allow clinical workers to personalized treatment more effectively in PDAC patients.

Identification of an RNA-Binding-Protein-Based Prognostic Model for Ewing Sarcoma.

RNA-binding proteins (RBPs) are important transcriptomic regulators and may be important in tumorigenesis. Here, we sought to investigate the clinical impact of RBPs for patients with Ewing sarcoma (ES). ES transcriptome signatures were characterized from four previously published cohorts and grouped into new training and validation cohorts. A total of three distinct subtypes were identified and compared for differences in patient prognosis and RBP signatures. Next, univariate Cox and Lasso regression models were used to identify hub prognosis-related RBPs and construct a prognostic risk model, and prediction capacity was assessed through time-dependent receiver operating characteristics (ROCs), Kaplan-Meier curves, and nomograms. Across the three RBP subtypes, 29 significant prognostic-associated RBP genes were identified, of which 10 were used to build and validate an RBP-associated prognostic risk model (RPRM) that had a stable predictive value and could be considered valuable for clinical risk-stratification of ES. A comparison with immunohistochemistry validation showed a significant association between overall survival and NSUN7 immunoreactivity, which was an independent favorable prognostic marker. The association of RBP signatures with ES clinical prognosis provides a strong rationale for further investigation into RBPs molecular mechanisms.