Jia-Jia Gu

MicroRNA-19b-3p regulates nasopharyngeal carcinoma radiosensitivity by targeting TNFAIP3/NF-κB axis

BackgroundNasopharyngeal carcinoma (NPC) is among the most common squamous cell carcinoma in South China and Southeast Asia. Radiotherapy is the primary treatment for NPC. However, radioresistance acts as a significant factor that limits the efficacy of radiotherapy for NPC patients. Growing evidence supports that microRNAs (miRNAs) play an important role in radiation response.MethodsReal-time quantitative PCR was used to analyze the expression of miR-19b-3p in NPC cell lines and NP69. miR-19b-3p expression profiles in NPC tissues were obtained from the Gene Expression Omnibus database. The effect of miR-19b-3p on radiosensitivity was evaluated by cell viability assays, colony formation assays and in vivo experiment. Apoptosis and cell cycle were examined by flow cytometry. Luciferase reporter assay was used to assess the target genes of miR-19b-3p. Expression of target proteins and downstream molecules were analyzed by Western blot.ResultsmiR-19b-3p was upregulated in NPC and served as an independent predictor for reduced patient survival. Radioresponse assays showed that miR-19b-3p overexpression resulted in decreased sensitivity to irradiation, whereas miR-19b-3p downregulation resulted in increased sensitivity to irradiation in vitro. Moreover, miR-19b-3p decreased the sensitivity of NPC cells to irradiation in vivo. Luciferase reporter assay confirmed that TNFAIP3 was a direct target gene of miR-19b-3p. Knockdown of TNFAIP3 reduced sensitivity to irradiation, whereas upregulation of TNFAIP3 expression reversed the inhibitory effects of miR-19b-3p on NPC cell radiosensitivity. Mechanistically, we found that miR-19b-3p increased NPC cell radioresistance by activating the TNFAIP3/ NF-κB axis.ConclusionsmiR-19b-3p contributes to the radioresistance of NPC by activating the TNFAIP3/ NF-κB axis. miR-19b-3p is a determinant of NPC radioresponse and may serve as a potential therapeutic target in NPC treatment.

Impact of plasma Epstein-Barr virus-DNA and tumor volume on prognosis of locally advanced nasopharyngeal carcinoma.

This retrospective study aims to examine the association of plasma Epstein-Barr virus- (EBV-) DNA levels with the tumor volume and prognosis in patients with locally advanced nasopharyngeal carcinoma (NPC). A total of 165 patients with newly diagnosed locally advanced NPC were identified from September 2011 to July 2012. EBV-DNA was detected using fluorescence quantitative polymerase chain reaction (PCR) amplification. The tumor volume was calculated by the systematic summation method of computer software. The median copy number of plasma EBV-DNA before treatment was 3790 copies/mL. The median gross tumor volume of the primary nasopharyngeal tumor (GTVnx), the lymph node lesions (GTVnd), and the total GTV before treatment were 72.46, 23.26, and 106.25 cm3, respectively; the EBV-DNA levels were significantly correlated with the GTVnd and the total GTV (P < 0.01). The 2-year overall survival (OS) rates in patients with positive and negative pretreatment plasma EBV-DNA were 100% and 98.4% (P = 1.000), and the disease-free survival (DFS) rates were 94.4% and 80.8% (P = 0.044), respectively. These results indicate that high pretreatment plasma EBV-DNA levels in patients with locally advanced NPC are associated with the degree of lymph node metastasis, tumor burden, and poor prognosis.

Radiosensitization Effect of Nedaplatin on Nasopharyngeal Carcinoma Cells in Different Status of Epstein-Barr Virus Infection

This study aims to evaluate the radiosensitization effect of nedaplatin on nasopharyngeal carcinoma (NPC) cell lines with different Epstein-Barr virus (EBV) status. Human NPC cell lines CNE-2 (EBV-negative) and C666 (EBV-positive) were treated with 0–100 μg/mL nedaplatin, and inhibitory effects on cell viability and IC50 were calculated by MTS assay. We assessed changes in radiosensitivity of cells by MTS and colony formation assays, and detected the apoptosis index and changes in cell cycle by flow cytometry. MTS assay showed that nedaplatin caused significant cytotoxicity in CNE-2 and C666 cells in a time- and dose-dependent manner. After 24 h, nedaplatin inhibited growth of CNE-2 and C666 cells with IC50 values of 34.32 and 63.69 μg/mL, respectively. Compared with radiation alone, nedaplatin enhanced the radiation effect on both cell lines. Nedaplatin markedly increased apoptosis and cell cycle arrest in G2/M phase. Nedaplatin radiosensitized human NPC cells CNE-2 and C666, with a significantly greater effect on the former. The mechanisms of radiosensitization include induction of apoptosis and enhancement of cell cycle arrest in G2/M phase.

Incorporation of alpha-fetoprotein(AFP) into subclassification of BCLC C stage hepatocellular carcinoma according to a 5-year survival analysis based on the SEER database

Purpose To evaluate the effect of serum alpha-fetoprotein(AFP) on prognosis of patients with hepatocellular carcinoma (HCC) and put forward a proposal to modify BCLC staging system and the recommended treatment of patients with stage C. Results AFP positive was an independent poor prognostic factor of HCC. Race, pathological grade, T stage, M stage were also regarded to be significant predicted factors for poorer prognosis. When combining AFP status with AJCC stage, patients with A1 disease had a worse prognosis compared with those with A0 disease within each stage. Patients with A1 disease of each T/N stage had a worse prognosis than patients with A0 disease of the respective stage, and the prognosis of patients with A1 disease with lower T stages was worse or similar to that of patients with A0 disease of higher T stages. Materials and Methods We performed a retrospective study of all patients histologically diagnosed HCC from January 1, 2004, through December 31, 2008, from the SEER database. Conclusions AFP can be used as a subclassification index to modify the AJCC staging system of HCC. Since BCLC stage is the most widely used staging system, we recommend routine pre-treatment AFP testing as standard of care in HCC and incorporate AFP status into the BCLC staging system to modify the recommended treatment of patients with stage C.

Cetuximab and Cisplatin Show Different Combination Effect in Nasopharyngeal Carcinoma Cells Lines via Inactivation of EGFR/AKT Signaling Pathway

Nasopharyngeal carcinoma (NPC) is a common malignant cancer in South China. Cisplatin is a classical chemotherapeutic employed for NPC treatment. Despite the use of cisplatin-based concurrent chemoradiotherapy, distant failure still confuses clinicians and the outcome of metastatic NPC remains disappointing. Hence, a potent systemic therapy is needed for this cancer. Epidermal growth factor receptor (EGFR) represents a promising new therapeutic target in cancer. We predicted that combining the conventional cytotoxic drug cisplatin with the novel molecular-targeted agent cetuximab demonstrates a strong antitumor effect on NPC cells. In this study, we selected HNE1 and CNE2 cells, which have been proved to possess different EGFR expression levels, to validate our conjecture. The two-drug regimen showed a significant synergistic effect in HNE1 cells but an additive effect in CNE2 cells. Our results showed that cisplatin-induced apoptosis was significantly enhanced by cetuximab in the high EGFR-expressing HNE1 cells but not in CNE2 cells. Further molecular mechanism study indicated that the EGFR/AKT pathway may play an important role in cell apoptosis via the mitochondrial-mediated intrinsic pathway and lead to the different antitumor effects of this two-drug regimen between HNE1 and CNE2 cells. Thus, the regimen may be applied in personalized NPC treatments.

Long-Term Results of Concurrent Chemoradiotherapy for Advanced N2-3 Stage Nasopharyngeal Carcinoma.

Background N-stage is related to distant metastasis in nasopharyngeal carcinoma (NPC) patients. The purpose of this study was to evaluate the efficacy and toxicity of different nedaplatin-based chemotherapy regimens in advanced N2-3 stage NPC patients treated with intensity modulated radiation therapy (IMRT). Patients and Methods Between April 2005 and December 2009, a total of 128 patients with N2-3 advanced NPC were retrospectively analyzed. Patients were treated with IMRT concurrent with 2 cycles of chemotherapy consisting of either nedaplatin plus paclitaxel (NP group, n = 67) or nedaplatin plus fluorouracil and paclitaxel (NFP group, n = 61). Two to four cycles of adjuvant chemotherapy were then administered every 21 days following concurrent chemoradiotherapy. Results With a median follow-up of 60 months, the 5-year overall survival (OS), progression-free survival (PFS), local-regional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) for all patients were 81.4%, 71.5%, 87.8% and 82.0%, respectively. No significant difference in PFS (66.6% vs. 76.7%, P = 0.212) and LRRFS rates (89.0% vs. 86.3%, P = 0.664) was observed between the NP and NFP groups. The 5-year OS (75.4% vs. 88.5%, P = 0.046) and DMFS (75.1% vs. 89.0%, P = 0.042) rate were superior in the NFP group compared with the NP group. The NFP group had a higher incidence of grade 3–4 acute toxicities including bone marrow suppression (leukopenia: χ2 = 3.935, P = 0.047; anemia: χ2 = 9.760, P = 0.002; thrombocytopenia: χ2 = 8.821, P = 0.003), and both liver and renal dysfunction (χ2 = 5.206, P = 0.023) compared with the NP group. Late toxicities were moderate and no difference was observed between the two groups. Conclusion IMRT concurrent with nedaplatin-based chemotherapy is an advocated regimen for patients with advanced N2-3 stage NPC. Patients with advanced N2-3 stage may be better candidates for the NFP regimen although this regimen was associated with a high acute toxicity rate.

TGF-β regulates the ERK/MAPK pathway independent of the SMAD pathway by repressing miRNA-124 to increase MALAT1 expression in nasopharyngeal carcinoma

Transforming growth factor beta (TGF-?), a pleiotropic cytokine, promotes cell proliferation and migration in multiple cancers, including nasopharyngeal carcinoma (NPC). microRNA-124 (miR-124) becomes downregulated in NPC and inhibits the tumorigenesis of this disease. However, the role of miR-124 in TGF-?-induced NPC development remains unknown. In this study, constant TGF-? stimulation repressed miR-124 expression, whereas miR-124 overexpression antagonized TGF-?-promoted NPC cell growth and migration. miR-124 overexpression decreased p-SMAD2/3, SMAD4, and p-ERK levels, indicating that ectopic miR-124 overexpression inhibited SMAD and non-SMAD pathways. Pro-oncogenic lncRNA MALAT1 was targeted by miR-124 that regulated ERK/MAPK by targeting MALAT1 independent of the SMAD signaling pathway. In conclusion, our work clarified the significant role of miR-124 in TGF-? signaling pathways independent of the SMAD signaling pathway and showed the potential of miR-124 as a new therapeutic target against NPC.

Progress of preoperative and postoperative radiotherapy in gastric cancer

BackgroundGastric carcinoma, a highly common malignant tumor, is treated mainly by surgery. Meanwhile, radiotherapy is attracting increased attention as a crucial locoregional therapy. However, the application of radiotherapy in gastric carcinoma is still limited and radiation standards remain debatable.Main bodyThe use of preoperative radiotherapy for treating gastroesophageal junction cancer has advanced. However, additional phase III clinical trials are needed to further verify the therapeutic value of preoperative radiotherapy for gastric cancer. Patients with D1 or D1 plus lymphadenectomy can benefit from postoperative radiotherapy obviously, and postoperative radiotherapy may be effective for patients with D2 lymphadenectomy with a high N stage. The target volume delineation of preoperative and postoperative radiotherapy should be based on clinical experience and the characteristics of lymphatic drainage.ConclusionsWith the advancement of radiotherapy technology, preoperative and postoperative radiotherapy are becoming increasingly accepted as important auxiliary treatments for gastric cancer.

Long non-coding RNA n326322 promotes the proliferation and invasion in nasopharyngeal carcinoma

Long non-coding RNAs (lncRNAs) have been reported to perform significant roles in cancer development and progression. Our research has found that a novel lncRNA n326322 was higher in nasopharyngeal carcinoma (NPC) cells. Moreover, the gain and loss of functional approaches revealed that the overexpression of lncRNA-n326322 promoted NPC cell proliferation and invasion, whereas the downregulation of lncRNA-n326322 suppressed cell proliferation and invasion. Further experiments demonstrated that potential mechanism may be associated with the activation of PI3K/AKT and ERK/MAPK pathways. Taken together, these results indicate that lncRNA-n326322 is associated with tumorigenesis of NPC.

MiR-152 functioning as a tumor suppressor that interacts with DNMT1 in nasopharyngeal carcinoma

Background In recent years, miR-152 has been dysregulated in a variety of tumors and used as a tumor suppressor. Nevertheless, its role in nasopharyngeal carcinoma (NPC) remains unidentified. Materials and methods Real-time quantitative PCR (polymerase chain reaction) was performed to analyze the expression of miR-152 in NPC cell lines. MiR-152 expression profiles in NPC tissues were obtained from Gene Expression Omnibus (GEO GSE36682). The effect of miR-152 on the invasion and proliferation of NPC cells was determined through cell invasion, wound healing, and cell viability assays. Apoptosis was examined by flow cytometry, and Western blot was performed to measure expression of the target gene. Pyrosequencing was used to detect the methylation level of NPC cells. Results In this study, miR-152 was downregulated in the NPC tissues and cell lines. When miR-152 was enhanced, the invasion and migration of NPC cells were inhibited. However, miR-152 had no effect on the proliferation of NPC cells. Luciferase reporter gene analysis was performed, and the results showed that DNMT1 (DNA (cytosine-5)-methyltransferase 1) is a direct target of miR-152 in NPC cells. DNMT1 downregulation and miR-152 overexpression both reversed the effects of miR-152 inhibition on the NPC cells. In addition, miR-152 expression increased as a result of the inhibition of the methylation level of miR-152 when DNMT1 expression was downregulated. Conclusion The overexpression of miR-152 inhibited the migration and invasion of NPC cells by targeting DNMT1. Furthermore, DNMT1 regulated miR-152 expression through DNA methylation. Overall, the novel miR-152-DNMT1 regulatory circuit may provide better understanding of the pathogenesis of NPC and new epigenetic therapeutic target in NPC.