Search

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor that commonly occurs worldwide. Usually, Asia, especially China, has a high incidence of esophageal cancer. ESCC often has a poor outcome because of a late diagnosis and lack of effective treatments. To build foundations for the early diagnosis and treatment of ESCC, we used the gene expression datasets GSE20347 and GSE17351 from the GEO database and a private dataset to uncover differentially expressed genes (DEGs) and key genes in ESCC. Notably, we found that replication factor C subunit 4 (RFC4) and guanine monophosphate synthase (GMPS) were upregulated but have been rarely studied in ESCC. In particular, to the best of our knowledge, our study is the first to explore GMPS and ESCC. Furthermore, we found that high levels of RFC4 and GMPS expression may result from an increase in DNA copy number alterations. Furthermore, RFC4 and GMPS were both upregulated in the early stage and early nodal metastases of esophageal carcinoma. The expression of RFC4 was strongly correlated with GMPS. In addition, we explored the relationship between RFC4 and GMPS expression and tumor-infiltrating immune cells (TILs) in esophageal carcinoma. The results showed that the levels of RFC4 and GMPS increased with a decrease in some tumor-infiltrating cells. Upregulated RFC4 and GMPS with high TILs indicate a worse prognosis. In summary, our study shows that RFC4 and GMPS have potential as biomarkers for the early diagnosis of ESCC and may played a crucial role in the process of tumor immunity in ESCC.

Background It has been known for years that the same genetic defects drive breast cancer formation, yet, the onset of breast cancer in different individuals among the same population differs greatly in their life spans with unknown mechanisms. Methods We used a MMTV-PyMT mouse model with different genetic backgrounds (FVB/NJ vs. C57BL/6J) to generate different cancer onset phenotypes, then profiled and analyzed the gene expression of three tumor stages in both Fvb.B6 and Fvb mice to explore the underlying mechanisms. Results We found that in contrast with the FVB/N-Tg (MMTV-PyMT) 634Mul mice (Fvb mice), mammary tumor initiation was significantly delayed and tumor progression was significantly suppressed in the Fvb.B6 mice (generated by crossing FVB/NJ with C57BL/6J mice). Transcriptome sequencing and analysis revealed that the differentially expressed genes were enriched in immune-related pathways. Flow cytometry analysis showed a higher proportion of matured dendritic cells in the Fvb.B6 mice. The plasma levels of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) were significantly reduced in the Fvb.B6 mice. IL-6 also impaired the maturation of bone marrow dendritic cells (BMDCs) of the Fvb mice in vitro. Conclusion All these findings suggest that immunity levels (characterized by a reduced IL-6 level and intact DC maturation in Fvb.B6 mice) are the key factors affecting tumor onset in a murine mammary cancer model.

Distant metastasis is the major cause of short survival in ccRCC patients. However, the development of effective therapies for metastatic ccRCC is limited. Herein, we reported that ETV4 was selected from among 150 relevant genes with in vivo evidence of promoting metastasis. In this study, we identified that ETV4 promoted ccRCC cell migration and metastasis in vitro and in vivo, and a positive correlation between ETV4 and FOSL1 expression was found in ccRCC tissues and cell lines. Further investigation suggested that ETV4 increase FOSL1 expression through direct binding with the FOSL1 promoter. Furthermore, ETV4/FOSL1 was proved as a novel upstream and downstream causal relationship in ccRCC in an AKT dependent manner. In addition, both ETV4 and FOSL1 serve as an independent, unfavorable ccRCC prognostic indicator, and the accumulation of the ETV4 and FOSL1 in ccRCC patients result in a worse survival outcome in ccRCC patients. Taken together, our results suggest that the ETV4/FOSL1 axis acts as a prognostic biomarker and ETV4 directly up-regulates FOSL1 by binding with its promoter in a PI3K-AKT dependent manner, leading to metastasis and disease progression of ccRCC.

The aldo‐keto reductases family 1 member C2 (AKR1C2) has critical roles in the tumorigenesis and progression of malignant tumours. However, it was also discovered to have ambiguous functions in multiple cancers and till present, its clinical significance and molecular mechanism in oesophageal squamous cell carcinoma (ESCC) has been unclear. The aim of this study was to explore the role of AKR1C2 in the tumorigenesis of ESCC. Here, we showed that AKR1C2 expression was found to be up‐regulated in ESCC tissues and was significantly associated with pathological stage, lymph node metastasis and worse outcomes. Functional assays demonstrated that an ectopic expression of AKR1C2 in ESCC cells resulted in increased proliferation, migration and cisplatin resistance, while knockdown led to inversing effects. Bioinformation analyses and mechanistic studies demonstrated that AKR1C2 activated the PI3K/AKT signalling pathway, furthermore, the inhibitor of PI3K or the selective inhibitor of AKR1C2 enzyme activity could reverse the aggressiveness and showed synergistic antitumour effect when combined with cisplatin, both in vitro and in vivo. In conclusion, Our findings revealed that AKR1C2 could function as an oncogene by activating the PI3K/AKT pathway, as a novel prognostic biomarker and/or as a potential therapeutic target to ESCC.

Nasopharyngeal carcinoma (NPC) is a unique head and neck cancer with highly aggressive and metastatic potential in which distant metastasis is the main reason for treatment failure. Till present, the underlying molecular mechanisms of NPC metastasis remains poorly understood. Here, we identified S100 calcium-binding protein A14 (S100A14) as a functional regulator suppressing NPC metastasis by inhibiting the NF-kB signaling pathway and reversing the epithelial-mesenchymal transition (EMT). S100A14 was found to be downregulated in highly metastatic NPC cells and tissues. Immunohistochemical staining of 202 NPC samples revealed that lower S100A14 expression was significantly correlated with shorter patient overall survival (OS) and distant metastasis-free survival (DMFS). S100A14 was also found as an independent prognostic factor for favorable survival. Gain- and loss-of-function studies confirmed that S100A14 suppressed the in vitro and in vivo motility of NPC cells. Mechanistically, S100A14 promoted the ubiquitin-proteasome-mediated degradation of interleukin-1 receptor-associated kinase 1 (IRAK1) to suppress NPC cellular migration. Moreover, S100A14 and IRAK1 established a feedback loop that could be disrupted by the IRAK1 inhibitor T2457. Overall, our findings showed that the S100A14-IRAK1 feedback loop could be a promising therapeutic target for NPC metastasis.

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors in China. However, there are no targets to treat ESCC because the molecular mechanism behind the cancer is still unclear. Here, we found a novel long noncoding RNA LINC02820 was upregulated in ESCC and associated with the ESCC clinicopathological stage. Through a series of functional experiments, we observed that LINC02820 only promoted the migration and invasion capabilities of ESCC cell lines. Mechanically, we found that LINC02820 may affect the cytoskeletal remodeling, interact with splice factor 3B subunit 3 (SF3B3), and cooperate with TNFα to amplify the NF-κB signaling pathway, which can lead to ESCC metastasis. Overall, our findings revealed that LINC02820 is a potential biomarker and therapeutic target for the diagnosis and treatment of ESCC.

Hong-Fa Xu,1,2,* Tie-Jun Huang,3,* Qin Yang,1 Liang Xu,1 Fen Lin,1 Yan-Hong Lang,1 Hao Hu,4 Li-Xia Peng,1 Dong-Fang Meng,1 Yu-Jie Xie,1 Li Tan,5 Chao-Nan Qian,1 Bi-Jun Huang11Department of Experimental Research, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou 510060, People’s Republic of China; 2Zhuhai Precision Medical Center, Zhuhai People’s Hospital Affiliated to Jinan University, Zhuhai 519000, People’s Republic of China; 3Department of Nuclear Medicine, The Second People’s Hospital of Shenzhen, Shenzhen 518035, People’s Republic of China; 4Department of Traditional Chinese Medicine, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510060, People’s Republic of China; 5Center of Hematology, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510230, People’s Republic of China*These authors contributed equally to this work Background/Aims: The tumor-suppressive functions of interferon regulatory factor 6 (IRF6) in some tumors have been preliminarily established, but its pathogenesis and underlying molecular mechanisms in breast cancer, the most common malignancy in women, remains poorly understood.Methods: Pairs of typical breast cancer cell lines (high- and low-aggressive) in addition to 27 breast cancer tissue samples and 31 non-cancerous breast tissues were used to investigate the expression level of IRF6 and Lentivirus-mediated gain-of-function studies, short hairpin RNA-mediated loss-of-function studies in vivo and in vitro were used to validate the role of IRF6 in breast cancer. Next, we performed RNA-Seq analysis to identify the molecular mechanisms of IRF6 involved in breast cancer progression.Results: Our findings showed that IRF6 was downregulated in highly invasive breast cancer cell lines but upregulated in poorly aggressive ones. Functional assays revealed that elevated IRF6 expression could suppress cell proliferation and tumorigenicity, and enhanced cellular chemotherapeutic sensitivity. To identify the molecular mechanisms involved, we performed a genome-wide and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in breast cancer cells using RNA sequencing of gene expression profiles following the overexpression of IRF6. Genome-wide and KEGG analyses showed that IRF6 might mediate the PI3K-regulatory subunit PIK3R2, which in turn modulated the PI3K/AKT pathway to control breast cancer pathogenesis.Conclusion: We provide the first evidence of the involvement of IRF6 in breast cancer pathogenesis, which was found to modulate the PI3K/AKT pathway via mediating PIK3R2; indicating that IRF6 can be targeted as a potential therapeutic treatment of breast cancer.Keywords: breast cancer, IRF6, proliferation, RNA sequencing, PIK3R2, PI3K/AKT

Purpose: Ultra-high dose rate FLASH irradiation has been shown to cause less normal tissue damage compared with conventional irradiation, also termed “FLASH effect”. However, the underlying mechanism was scarcely known. The purpose of the present study was to determine whether FLASH and conventional irradiation would induce differential inflammatory cytokines expression. Materials and methods: Female FvB mice were randomly assigned to three different groups: non-irradiated control, conventional (CONV) and FLASH groups. Mice were irradiated at 6 to 19 Gy of CONV (0.1 Gy/s) or FLASH (38.5-600 Gy/s) irradiation using an Elekta Synergy linac (6 MeV). Mice were immobilized in prone position in a custom-designed applicator with dosimetry films positioned under the body. Dose were verified by Gafchromic films. Enzyme linked immunosorbent assay (ELISA) were performed in serum samples of the mice at 6, 18 and 31 days after irradiation for four inflammatory cytokines: tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-6 (IL-6) and IL-10. Flow cytometry using antibodies for CD3, CD8, CD4 and CD45 in blood were performed pre- and 1-week post irradiation. Results: At D6 (18-19 Gy), both IL-6 and TNF-α were elevated, and IL-10 was reduced in FLASH and CONV group, while IFN-γ was only significantly increased in conventional group, compared with control group. At D18 (10 Gy) and D31 (13-19 Gy), conventional RT significantly elevated levels of IL-6, IFN-γ and TNF-α and reduced IL-10 level compared with FLASH group and control group. Additionally, even low dose conventional irradiation (13 Gy) could induce higher level of pro-inflammatory cytokines and lower level of anti-inflammatory cytokine than high dose (17-19 Gy) FLASH irradiation at D31. Flow cytometry showed that the CD8+/CD45+ ratio in the blood were higher in the conventional than in FLASH. These data indicate that minor inflammatory cytokine levels of serum in FLASH could be result of the absent of immune overactivation induced by conventional irradiation. Conclusions: Ultra-high dose rate electron FLASH caused less inflammatory cytokine levels of serum which might be a result from less CD8+/CD45+ ratio in the blood. Thus, differential cytokines and CD8+ T cell expression between FLASH and conventional irradiation would be a potential mechanism for “FLASH effect”.

Purpose/Objective(s) To clarify the efficacy of FLASH radiotherapy (FLASH-RT) in inhibiting mammary tumorigenesis and normal tissue sparing. Materials/Methods We used a spontaneous mammary tumor model of MMTV-PyMT mice for the study. Prior to the formation of mammary tumor, MMTV-PyMT mice (3–6-week-old) were treated with a single fraction dose of 9-16 Gy FLASH-RT or conventional radiotherapy (CONV-RT) using a mice-applicator designed targeting five pair of mammary glands. Tumor growth was detected by thorough palpation of all 10 mammary glands twice a week. Liver function, HE however, IFN-g and IL-6 also significantly increased in FLASH compared with control, while IL-10 significantly decreased in CONV compared with control. Serum IL-6, IFN-g and TNF-a levels in FLASH did not markedly change on D6, D18 and D31 post-IR compared with control. Serum IL-6, IFN-g and TNF-a levels were elevated on D6 and continuously increased on D18 and D31 in CONV, but began to increase on D6, and then recovered to the control level on D18 or D31 in FLASH. Serum IL-10 levels decreased at D6, D18 and D31 in CONV, but began to decrease at D6, and then recovered to the control level at D18 or D31 in FLASH. FLASH induced reactive oxygen species (ROS) accumulation in the tumor tissue but not in normal tissue; while absence of ROS accumulation in either tumor or normal tissue under CONV. Notably, the ROS level of normal liver tissue did not differ under CONV or FLASH. Conclusion We found that mammary tumorigenesis was inhibited by FLASH without significant liver injury compared with CONV-RT. The alteration of serum and liver inflammatory cytokines induced by CONV-RT was mildly altered by FLASH. This unique benefit can by partially explained by the accumulatio of ROS in tumor tissue after FLASH.

Background: The extracellular matrix (ECM) component serglycin promotes the epithelial-to-mesenchymal transition (EMT) and metastasis in an autocrine manner. However, the detailed mechanism underlying the roles of serglycin in Hepatocellular carcinoma (HCC) metastasis progression remains to be clarified.Methods: Analyzing 123 patients’ serum by ELISA to investigate the association between serglycin expression and HCC metastasis and prognosis. Serglycin, CRISPLD2, and YAP were overexpressed or knocked down with vector or RNAi. The RNA - sequence was used to screen serglycin downstream effectors, followed by bioinformatics, ChIP-PCR, luciferase, and promoter site mutation to identify novel target genes. The metastatic abilities of serglycin were demonstrated by a series of in vitro and in vivo experiments. Immunofluorescence, flow cytometry, and western blotting were carried out to demonstrate the potential mechanisms of serglycin.Results: We observed that serglycin was overexpressed in HCC tissues and serum, and its level was associated with metastasis and poor prognosis. By gain- and loss-of-function approaches, we found serglycin affects migratory motility and metastatic capacity in vitro and in vivo, and it's significantly associated with the stemness-like properties. Interestingly, serglycin activated the effector YAP of Hippo pathway, and further study verified the crucial role of serglycin/YAP in tumorigenesis by the DEN-induced HCC mouse model. Furthermore, the CRISPLD2 was selectively upregulated by serglycin, the axis of serglycin / YAP / CRISPLD2 regulated metastatic capacity in HCC cells, it revealed CRISPLD2 was the direct target gene of serglycin-mediated YAP/TEAD1 complex. Besides, serglycin-mediated YAP pathway enhanced cell sorafenib resistance, sorafenib combined with verteporfin reversed serglycin-mediated cellular insensitivity to sorafenib therapy.Conclusions: Autocrine ECM serglycin plays a crucial role in the process of stemness maintenance, tumorigenesis, and metastasis via selective reactivation of the novel YAP/CRISPLD2 developmental axis promotes metastasis and sorafenib resistance in Hepatocellular carcinoma, YAP-TEAD1 inhibitor verteporfin reversed serglycin-mediated cellular sorafenib resistance.

Nasopharyngeal carcinoma (NPC) originates in the nasopharyngeal epithelium and has the highest metastatic rate among head and neck cancers. Distant metastasis is the main reason for treatment failure with the underlying mechanisms remaining unclear. By comparing the expression profiling of NPCs versus non-cancerous nasopharyngeal tissues, we found LACTB was highly expressed in the tumor tissues. We found that elevated expression of the LACTB protein in primary NPCs correlated with poorer patient survival. LACTB is known to be a serine protease and a ubiquitous mitochondrial protein localized in the intermembrane space. Its role in tumor biology remains controversial. We found that the different methylation pattern of LACTB promoter led to its differential expression in NPC cells. Overexpressing LACTB in NPC cells promoted their motility in vitro and metastasis in vivo. While knocking down LACTB reduced the metastasis capability of NPC cells. However, LACTB did not influence cellular proliferation. We further found the role of LACTB in promoting NPC metastasis depended on the activation of ERBB3/EGFR-ERK signaling, which in turn, affected the stability and the following acetylation of histone H3. These findings may shed light on unveiling the mechanisms of NPC metastasis.

It is believed that the alteration of tissue microenvironment would affect cancer initiation and progression. However, little is known in terms of the underlying molecular mechanisms that would affect the initiation and progression of breast cancer. In the present study, we use two murine mammary tumor models with different speeds of tumor initiation and progression for whole genome expression profiling to reveal the involved genes and signaling pathways. The pathways regulating PI3K-Akt signaling and Ras signaling were activated in Fvb mice and promoted tumor progression. Contrastingly, the pathways regulating apoptosis and cellular senescence were activated in Fvb.B6 mice and suppressed tumor progression. We identified distinct patterns of oncogenic pathways activation at different stages of breast cancer, and uncovered five oncogenic pathways that were activated in both human and mouse breast cancers. The genes and pathways discovered in our study would be useful information for other researchers and drug development.

Background CLCA2 was reported as a tumor suppressor and disregulated in breast cancer. However, its function in tumor growth and metastasis in NPC has rarely been reported. In this study, we investigated the functional and molecular mechanisms by which CLCA2 influences NPC. Methods CLCA2 expression in human NPC cell lines and tissues was examined via real-time PCR (RT-PCR), Western blot and IHC. The biological roles of CLCA2 in proliferative, migration and invasion of NPC cell lines was evaluated in 5-8F, S18, S26 and SUNE-1 cells. Cell viability, migration and invasion were assessed in vitro by MTS, colony formation and transwell assay, respectively. CLCA2 in growth and metastasis of NPC were evaluated in vivo through NPC xenograft tumor growth, lung metastatic mice model and popliteal lymph node (LN) metastasis model. Results Overexpression of CLCA2 significantly decreased proliferation, migration and invasion of NPC cells. In contrast, knockdown of CLCA2 elicited the opposite effects. CLCA2 overexpression suppressed xenograft tumor growth and lung, popliteal lymph node (LN) metastasis in vivo. CLCA2 inhibited tumor metastasis through suppressing epithelial-Mesenchymal transition (EMT) and in-activating FAK/ERK1/2 signaling pathway in NPC cells. Immunohistochemical staining of 143 NPC samples revealed that CLCA2 expression was an independent, favorable prognostic factor for overall survival and distant metastasis-free survival of patients. In addition, inhibition of FAK and ERK1/2 reversed CLCA2 silencing-induced tumor cell migration. Furthermore, inhibitors against chloride channels suppressed NPC cellular migration which could have been enhanced by the presence of CLCA2. Conclusion CLCA2 suppress NPC proliferation, migration, invasion and epithelial-mesenchymal transition through inhibiting FAK/ERK signaling. Electronic supplementary material The online version of this article (10.1186/s13046-018-0692-8) contains supplementary material, which is available to authorized users.

Nasopharyngeal carcinoma (NPC) is relatively sensitive to ionizing radiation, and radiotherapy is the main treatment modality for non-metastatic NPC. Radiation therapy generates overproduction of reactive oxygen species (ROS), which can cause DNA damage and induce apoptosis in tumors, thereby killing the malignant cells. Although dietary antioxidant supplementation reduces oxidative stress and promotes tumor progression, the effects of antioxidants on the NPC cells upon radiation have not been reported. In the present study, we showed that antioxidants (β-Carotene, NAC, GSH) played an anti-apoptotic role in response to radiation via decreasing ROS production and inhibiting MAPK pathway in NPC cells. Based on that, we conclude that the use of supplemental antioxidants during radiotherapy should be avoided because of the possibility of tumor protection and reduced treatment efficacy.

The underlying molecular mechanism driving clear cell renal cell carcinoma (ccRCC) progression is still to be explored. The significant downregulation of protein tyrosine phosphatase nonreceptor type 3 (PTPN3) expression in the tumor tissues suggested its protective role in ccRCC progression. IHC analysis of PTPN3 protein in 172 ccRCC tissue revealed that PTPN3 was an independently favorable prognostic factor for progression-free survival (P = 0.0166) and overall survival (P = 0.0343) of patients. The ccRCC cell lines SN12C, 1932, ACHN, and Caki-1 were used to evaluate, both in vitro and in vivo, the biological roles of PTPN3. We observed that overexpression of PTPN3 significantly inhibited the proliferation, migration, and invasion of ccRCC cells. In contrast, the knocking down of PTPN3 elicited opposite effects. Overexpressing PTPN3 inhibited xenograft tumor growth and lung metastasis displayed by the in vivo mice models. PTPN3 inhibited tumor cell motility by suppressing the phosphorylation of AKT, and subsequently inactivating the PI3K/AKT signaling pathway of renal cell carcinoma cells. Furthermore, the inhibition of phospho-AKTThr308 and phospho-AKTSer473 reversed PTPN3-induced silencing in tumor cell migration. Our work revealed that the overexpression of PTPN3 could suppress kidney cancer progression by negatively regulating the AKT signaling pathway, and served as a favorable prognostic factor in patients with ccRCC. Our findings provided insight that PTPN3 could be a potential target for therapy aiming to inhibit the malignant behaviors of ccRCC. Implications: PTPN3 is an independent favorable prognostic factor for patients with ccRCC and could be a potential target for therapy aiming to inhibit the malignant behaviors of ccRCC.

Background With the rapid development of the high throughput detection techniques, tumor-related Omics data has become an important source for studying the mechanism of tumor progression including breast cancer, one of the major malignancies worldwide. A previous study has shown that the G2 and S phase-expressed-1 (GTSE1) can act as an oncogene in several human cancers. However, its functional roles in breast cancer remain elusive. Method In this study, we analyzed breast cancer data downloaded from The Cancer Genome Atlas (TCGA) databases and other online database including the Oncomine, bc-GenExMiner and PROGgeneV2 database to identify the molecules contributing to the progression of breast cancer. The GTSE1 expression levels were investigated using qRT-PCR, immunoblotting and IHC. The biological function of GTSE1 in the growth, migration and invasion of breast cancer was examined in MDA-MB-231, MDA-MB-468 and MCF7 cell lines. The in vitro cell proliferative, migratory and invasive abilities were evaluated by MTS, colony formation and transwell assay, respectively. The role of GTSE1 in the growth and metastasis of breast cancer were revealed by in vivo investigation using BALB/c nude mice. Results We showed that the expression level of GTSE1 was upregulated in breast cancer specimens and cell lines, especially in triple negative breast cancer (TNBC) and p53 mutated breast cancer cell lines. Importantly, high GTSE1 expression was positively correlated with histological grade and poor survival. We demonstrated that GTSE1 could promote breast cancer cell growth by activating the AKT pathway and enhance metastasis by regulating the Epithelial-Mesenchymal transition (EMT) pathway. Furthermore, it could cause multidrug resistance in breast cancer cells. Interestingly, we found that GTSE1 could regulate the p53 function to alter the cell cycle distribution dependent on the mutation state of p53. Conclusion Our results reveal that GTSE1 played a key role in the progression of breast cancer, indicating that GTSE1 could serve as a novel biomarker to aid in the assessment of the prognosis of breast cancer. Electronic supplementary material The online version of this article (10.1186/s13046-019-1157-4) contains supplementary material, which is available to authorized users.

Nasopharyngeal carcinoma (NPC) has the highest metastatic rate among head and neck cancers, with its underlying mechanism not yet fully unveiled. High- versus low-metastasis, NPC cell lines have been established. The footpad-popliteal lymph node metastasis model and other in vivo models have been stably used to study NPC metastasis. The histological appearance and the expression of epithelial-to-mesenchymal transition (EMT) markers might be helpful in selecting high-risk NPC patients for developing post-treatment metastasis. Tested EMT markers and their protein expression levels that correlate with patient disease-free survival in large patient cohorts include E-cadherin, N-cadherin, CD44, Twist, Snail, and Cyclin D1. Epstein-Barr virus (EBV) infection can trigger NPC metastasis from multiple angles via multiple signaling pathways. High endothelial venules are commonly seen in NPC tissues, with their role in NPC metastasis requiring clarification. The molecules that promote and inhibit NPC metastasis are introduced, with a focus on cytokines SPINK6, serglycin, interleukin 8 (IL8), Wnt family member 5A (WNT5A), and chemokine C-C motif ligand 2 (CCL2). Two videos showing NPC cells with and without SPINK6 knocked down are presented. Future directions for studying NPC metastasis are also discussed.

Cancer patients are more susceptible to severe coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Angiotensin-converting enzyme 2 (ACE2) is the functional host receptor for SARS-CoV-2 entering into human cells. Bioinformatics’ analyses have revealed that ACE2 is upregulated in some cancer cells. In the present study, we evaluated ACE2 protein expression levels in several common malignancies compared to non-cancerous normal tissues. ACE2 expression was elevated in colorectal adenocarcinoma, pancreatic adenocarcinoma, gastric adenocarcinoma, and papillary renal cell carcinoma cancer. Yet, it was suppressed in chromophobe renal cell carcinoma, testicular germ cell tumors, and papillary thyroid carcinoma. Two tumor tissue microarrays were used to evaluate the prognostic value of ACE2 expression in patients with gastric adenocarcinoma, and colorectal adenocarcinoma without COVID-19. No significant survival benefit was found for patients with overexpression of ACE2 in the tumor. In the tumor vasculature, ACE2 expression was observed in only 54% of the tumor micro-vessels. Using an in vitro co-culture of endothelial cells and tumor cells overexpressing fusion protein ACE2-red fluorescent protein, we did not observe any clear and convincing intercellular transfer of ACE2 from cancer cells into endothelial cells. In summary, alteration of ACE2 expression was found in common malignancies, but there is no evidence of intercellular transfer of ACE2 from cancer cells to endothelial cells.

Nasopharyngeal carcinoma (NPC) is well known as one of the most common malignancies in southern China and Southeast Asia. However, the mechanisms underlying NPC progression remain poorly understood. Herein, through overlapping the differentially expressed genes from 3 microarray data sets with the human kinome, we identified PBK, a serine-threonine kinase, is highly upregulated and has not been intensively investigated in NPC. PBK was required for malignant phenotypes of NPC, as PBK depletion by RNAi and inhibition by specific inhibitor HI-TOPK-032 obviously reduced cell proliferation and xenograft tumor growth in mice. Moreover, we determined that targeting PBK could accelerate apoptosis by inducing ROS that activates JNK/p38 signaling pathway. In NPC patients, elevated PBK expression in primary tumor positively correlated to clinical severity such as advanced T stage, high death risk and disease progression, and it could serve as an unfavorable independent indicator of overall survival and disease-free survival. Altogether, our results indicate that PBK is a novel significant regulator of NPC progression and a potential therapeutic target for NPC patients.

Our previous study reported that Epstein-Barr virus(EBV)-encoded latent membrane protein 1 (LMP1) could induce development of CD44(+/High) stem-like cells in nasopharyngeal carcinoma (NPC). However, the molecular mechanisms that underlie modulation of cancer stem cells (CSCs) in NPC remain unclear. Here, we show that LMP1 induced CSC-like properties through promotion of the expression of epithelial-mesenchymal transition-like cellular markers and through alterations in differentiation markers. Furthermore, LMP1 activated and triggered phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, which subsequently stimulated expression of CSC markers, development of side population and tumor sphere formation. This suggests that PI3K/AKT pathway has an important role in the induction and maintenance of CSC properties in NPC. Similarly, PI3K/AKT pathway was also activated by phosphorylase in LMP1-induced CD44(+/High) cells. In addition, LMP1 greatly increased expression of miR-21 and downregulated expression of the miR-21 target, PTEN. Overexpression of miR-21 by transfection of miR-21 mimics into LMP1-transformed cells led to phosphorylase-mediated activation of the PI3K/AKT pathway and induction of CSCs. On the contrary, phosphorylation of the PI3K/AKT pathway and the expression of CSC were reversed by an miR-21 inhibitor. The specific inhibitor (Ly294002) of PI3K/AKT pathway significantly decreased expression of miR-21 and CSC markers and upregulated the expression of PTEN, which indicates that miR-21 and PTEN are the downstream effectors of PI3K/AKT and that expression of these two effectors are related to the development of NPC CSCs. Taken together, our novel findings indicate that LMP1, PI3K/AKT, miR-21 and PTEN constitute a positive feedback loop and have a key role in LMP1-induced CSCs in NPC.

Nasopharyngeal carcinoma (NPC) has the highest metastasis rate among head and neck cancers with unclear mechanism. WNT5A belongs to the WNT family of cysteine-rich secreted glycoproteins. Our previous high-throughput gene expression profiling revealed that WNT5A was up-regulated in highly metastatic cells. In the present study, we first confirmed the elevated expression of WNT5A in metastatic NPC tissues at both the mRNA and protein levels. We then found that WNT5A promoted epithelial-mesenchymal transition (EMT) in NPC cells, induced the accumulation of CD24-CD44+ cells and side population, which are believed to be cancer stem cell characteristics. Moreover, WNT5A promoted the migration and invasion of NPC cells in vitro, while in vivo treatment with recombinant WNT5A promoted lung metastasis. Knocking down WNT5A diminished NPC tumorigenesis in vivo. When elevated expression of WNT5A coincided with the elevated expression of vimentin in the primary NPC, the patients had a poorer prognosis. Among major signaling pathways, protein kinase C (PKC) signaling was activated by WNT5A in NPC cells. A positive feedback loop between WNT5A and phospho-PKC to promote EMT was also revealed. Taken together, these data suggest that WNT5A is an important molecule in promoting stem cell characteristics in NPC, leading to tumorigenesis and metastasis.

Nasopharyngeal carcinoma (NPC), which originates from the nasopharynx, is highly prevalent in Southern China and Southeast Asia, and more than 90% of all NPCs are non-keratinizing undifferentiated cells or poorly differentiated squamous cells. Cancer stem cells (CSCs) are capable of self-renewal and have differentiation potential. These properties form the basis of cancer initiation, development, and radiochemoresistance. However, the molecular mechanisms underlying NPC CSC maintenance remain poorly understood. Here, genomic expression profiling using our previously established monoclonal cellular and animal models revealed that interferon regulatory factor 6 (IRF6) was downregulated in highly metastatic NPC cells, cancer stem-like NPC cells and animal models. Functional assays revealed that elevated IRF6 expression suppressed cell proliferation, growth, CSCs properties and enhanced cell chemotherapeutic sensitivity. However, silencing IRF6 resulted in opposing effects. Moreover, we determined that as a tumor suppressor gene and transcription factor, IRF6 directly bound the upstream region of the ATP-binding cassette sub-family G member 2 (ABCG2) DNA element and suppressed target ABCG2 expression in NPC cells. Consistently, an inverse correlation was observed between the mRNA levels of IRF6 and ABCG2 in clinical NPC samples. With these results, we provide the first evidence that IRF6 directly targets the ABCG2 gene and selectively kills CSCs in NPC and that IRF6 may be a valuable tool for developing new CSC-targeted treatment strategies for undifferentiated NPC patients.

Emerging evidence confirms that cancer stem cells (CSCs) are responsible for the chemoradioresistance of malignancies. EBV-encoded latent membrane protein 1 (LMP1) is associated with tumor relapse and poor prognosis of nasopharyngeal carcinoma (NPC). However, whether LMP1 induces the development of CSCs and the mechanism by which this rare cell subpopulation leads to radioresistance in NPC remain unclear. In the present study, LMP1-transformed NPC cells showed significant radioresistance compared to the empty vector control. We found that LMP1 up-regulated the expression of several stemness-related genes, increased the cell number of side population (SP) by flow cytometry analysis, enhanced the self-renewal properties of the cells in a spherical culture and enhanced the in vivo tumor initiation ability. We also found that LMP1 positively regulated the expression of the CSC marker CD44. The CD44(+/High) subpopulation of the LMP1-transformed NPC cells displayed more significant CSC characteristics than the CD44(-/Low) subpopulation of the LMP1-transformed NPC cells; these characteristics included the upregulation of stemness-related genes, in vitro self-renewal and in vivo tumor initiation ability. Importantly, the CD44(+/High) subpopulation displayed more radioresistance than the CD44(-/Low) subpopulation. Our results also demonstrated that phosphorylation of the DNA damage response (DDR) proteins, ATM, Chk1, Chk2 and p53, was inactivated in the LMP1-induced CD44(+/High) cells in response to DNA damage, and this was accompanied by a downregulation of the p53-targeted proapoptotic genes, which suggested that the inactivation of the p53-mediated apoptosis pathway was responsible for the radioresistance in the CD44(+/High) cells. Taken together, we found that LMP1 induced an increase in CSC-like CD44(+/High) cells, and we determined the molecular mechanism underlying the radioresistance of the LMP1-activated CSCs, highlighting the need of CSC-targeted radiotherapy in EBV-positive NPC.

An E1B55K-attenuated adenovirus, dl1520, has been shown to replicate selectively in and lyse tumor cells. In this study, the antitumor activities of dl1520, alone or in combination with the chemotherapeutic agent cisplatin, were investigated in nasopharyngeal carcinoma (NPC) cells. The results demonstrated that dl1520 replicated in and destroyed NPC cells, and induced apoptosis in vitro. In a nude mouse xenograft model, dl1520 significantly inhibited the growth of NPC cell xenografts, and the viral replication was associated with tumor regression. Importantly, the antitumor activity of dl1520 was augmented by the addition of cisplatin both in vitro and in vivo, showing that dl1520 and cisplatin have a synergistic anti-NPC effect. These data suggest that dl1520 exerts an efficient anti-NPC activity through oncolysis and the induction of apoptosis, which is enhanced synergistically by cisplatin. These findings indicate that oncolytic viral therapeutics using the E1B55K-attenuated adenovirus dl1520 could be promising in the comprehensive treatment of NPC, especially in combination with platinum-based chemotherapy.

Based on microarray analysis, we previously reported that miR-29c is significantly downregulated in nasopharyngeal carcinoma (NPC). However, little is known about the effect and molecular mechanisms of action of miR-29c deregulation during the development and progression of NPC. Quantitative RT-PCR demonstrated that miR-29c was significantly downregulated in NPC cell lines and clinical specimens. Wound healing, Transwell migration and lung metastasis assays demonstrated that ectopic expression of miR-29c inhibited NPC cell migration and invasion in vitro and suppressed the formation of lung metastases in vivo. T cell lymphoma invasion and metastasis 1 (TIAM1) was confirmed as a miR-29c target gene using luciferase reporter assays, quantitative RT-PCR and Western blotting. Ectopic expression of TIAM1 significantly promoted the migration and invasion of SUNE-1 cell line stably overexpressing miR-29c. The prognostic value of TIAM1 was analyzed in 217 NPC patients using immunohistochemistry. Strikingly, patients with high TIAM1 expression had poorer overall, disease-free and distant metastasis-free survival than patients with low TIAM1 expression. Furthermore, multivariate Cox regression analysis revealed that TIAM1 could serve as an independent prognostic factor in NPC. The newly identified miR-29c/TIAM1 pathway further elucidates the molecular mechanisms regulating invasion and metastasis in NPC, and may provide novel prognostic and treatment strategies for NPC patients.

Nasopharyngeal carcinoma has the highest rate of metastasis among head and neck cancers, and distant metastasis is the major reason for treatment failure. The underlying molecular mechanisms of nasopharyngeal carcinoma metastasis are not fully understood. Here, we report the identification of serine protease inhibitor Kazal-type 6 (SPINK6) as a functional regulator of nasopharyngeal carcinoma metastasis via EGFR signaling. SPINK6 mRNA was upregulated in tumor and highly metastatic nasopharyngeal carcinoma cells. Immunohistochemical staining of 534 nasopharyngeal carcinomas revealed elevated SPINK6 expression as an independent unfavorable prognostic factor for overall, disease-free, and distant metastasis–free survival. Ectopic SPINK6 expression promoted in vitro migration and invasion as well as in vivo lymph node metastasis and liver metastasis of nasopharyngeal carcinoma cells, whereas silencing SPINK6 exhibited opposing effects. SPINK6 enhanced epithelial–mesenchymal transition by activating EGFR and the downstream AKT pathway. Inhibition of EGFR with a neutralizing antibody or erlotinib reversed SPINK6-induced nasopharyngeal carcinoma cell migration and invasion. Erlotinib also inhibited SPINK6-induced metastasis in vivo. Notably, SPINK6 bound to the EGFR extracellular domain independent of serine protease–inhibitory activity. Overall, our results identified a novel EGFR-activating mechanism in which SPINK6 has a critical role in promoting nasopharyngeal carcinoma metastasis, with possible implications as a prognostic indicator in nasopharyngeal carcinoma patients. Cancer Res; 77(2); 579–89. ©2016 AACR.

Vasculogenic mimicry (VM) is the formation of vascular channels by tumor cells or tumor cell-derived, trans-differentiated cells in highly aggressive, solid tumors. However, the disease features and prognostic value of VM for overall survival of cancer patients remain controversial. To systematically investigate the roles of VM in cancer progression and its prognostic values, we performed a meta-analysis based on 36 studies (33 eligible articles) including 3609 patients. The pooled hazard ratios (HRs) with 95 % confidence intervals (95 % CIs) were used to assess the relationship between VM and overall survival in cancer patients. Vasculogenic mimicry was significantly associated with cancer differentiation, lymph node metastasis, distant metastasis, and TNM stage. The prognostic value of VM was significant in overall survival (HR 2.16; 95 % CI 1.98–2.38; P

Nasopharyngeal carcinoma (NPC) has the highest metastasis potential among head and neck cancers. Distant metastasis is the major cause of treatment failure. Recent studies from our laboratory have revealed that IL-8 promotes NPC metastasis via activation of AKT signaling and induction of epithelial-mesenchymal transition (EMT) in the cells. In the present study, we found that IL-8 treatment for NPC cells resulted in an accumulation of DNMT1 protein through activating AKT1 pathway and consequent DNMT1 protein stabilization. Then DNMT1 suppressed E-cadherin expression by increasing the methylation of its promoter region. LY-294002 blocked IL-8-induced p-AKT1 activation resulting in reduction of DNMT1 and increase of E-cadherin expression, whereas forced demethylation using 5-aza-2'-deoxycytidine restored E-cadherin expression. In conclusion, our study, for the first time, shows that the IL-8/AKT1 signaling pathway stabilizes DNMT1 protein, consequently enhancing hypermethylation of E-cadherin promoter regions and downregulating E-cadherin protein level in NPC cells. Upon blockage of the IL-8/AKT pathway and inhibition of DNMT1, E-cadherin expression can be reversed. These data suggest that targeting the IL-8/AKT1 signaling pathway and DNMT1 may provide a potential therapeutic approach for blocking NPC metastasis.

The causative agent of severe acute respiratory syndrome (SARS) has been identified as SARS-associated coronavirus (SARS-CoV), but the prophylactic treatment of SARS-CoV is still under investigation. We constructed a recombinant adenovirus containing a truncated N-terminal fragment of the SARS-CoV Spike (S) gene (from--45 to 1469, designated Ad-S(N)), which encoded a truncated S protein (490 amino-acid residues, a part of 672 amino-acid S1 subunit), and investigated whether this construct could induce effective immunity against SARS-CoV in Wistar rats. Rats were immunized either subcutaneously or intranasally with Ad-S(N) once a week for three consecutive weeks. Our results showed that all of the immunized animals generated humoral immunity against the SARS-CoV spike protein, and the sera of immunized rats showed strong capable of protecting from SARS-CoV infection in vitro. Histopathological examination did not find evident side effects in the immunized animals. These results indicate that an adenoviral-based vaccine carrying an N-terminal fragment of the Spike gene is able to elicit strong SARS-CoV-specific humoral immune responses in rats, and may be useful for the development of a protective vaccine against SARS-CoV infection.

Objective: To construct a fine map of the loss of chromosome Ipter-p36.11 region in nasopharyngeal carcinoma (NPC) using PCR-LOH technique. Methods: DNA extracted from separated cancerous cells and their mated noncancerous lymphocytes from 47 cases of NPC biopsies were analyzed by means of PCR-LOH to detect 20 loci spanning chromosome Ipter-p36.11 region in NPC. Results: In 47 NPC cases, 37 (82.2%) cases showed at least one loci LOH. The highest frequency of less of heterozygosity (LOH) at all 20 loci was found at loci DIS234 (50. 0%) on 1p36.13 and loci DIS2644 (37.5%) on 1p36.22. There was a statistically significant difference between DIS234 LOH frequency (60%, 9/15) in early stage and that (50. 0%, 8/16) in advanced stage (P>0.05). Of all 20 STSs (sequence tqgged-site, STS), DIS243 (37.5%) and DIS199 (30.2%) showed the highest frequency of MI (microsatellite instability) on 1p36.33 and 1p36.21, respectively. In addition, several cases showed a contiguous stretch of allelic loss in a different level. Conclusion: Two minimal deletion regions (MDR) on the short arm of chromosome 1 were seated at 1p36.13 (DIS234, 2.0 cm) and 1p36.22 (DIS436-DIS2644, 6.3 cm) respectively, indicating that one or more candidate tumor suppressor gene (TSG) in the two regions may be involved in NPC pathogenesis in an early clinical stage.

HER2 (c-erbB-2) has been suggested to be a prognostic factor in a variety of human cancers including breast, gastric and ovarian cancers. This study is therefore designed to identify changes of HER2 in nasopharyngeal carcinoma (NPC), an epithelia-derived malignancy with strong racial and geographic distribution. Interphase FISH and immunohistochemical (IHC) staining were used to analyze the gene copy number and protein expression of HER2 in 45 cases of NPC from Guangzhou, Southern China, an area with the highest incidence of NPC in the world. Our results, however, found no significant alterations in gene copy number for HER2, although IHC staining detected expression of HER2 oncoprotein in 33% of the 45 NPC tumors. No correlation was observed between HER2 expression and sex, age and clinical outcome of the patients, T stage, lymph node status, site and histopathological grading of the tumors. These results cast doubt on the value of HER2 as a prognostic factor for NPC.

Nasopharyngeal carcinoma (NPC), is one of the most common human malignancies in south China, it has the highest recurrence rate and treatment resistance. The underlying molecular mechanisms of NPC relapse and treatment tolerance are not fully understood. In this study, the effects of NEDD8 and NEDD8-activating enzyme inhibitor (MLN4924) on NPC were studied both in vitro and in vivo. Immunohistochemical staining of 197 NPC tissues revealed an elevated NEDD8 expression as an unfavorable independent factor in overall survival and disease-free survival rates. NEDD8 expression was positively correlated with a high risk of death and positivity of lymph node metastasis. Depleted NEDD8 expression by shRNA and inhibited by specific inhibitor MLN4924 dramatically suppressed cell proliferation, cell apoptosis, cell cycle arrest, while ectopic NEDD8 exhibited opposing effects. NEDD8 affected cancer stem cell phenotypes of NPC as assessed in vitro using the cell number of side population (SP) by flow cytometry analysis, colony formation assay, sphere formation assay, and tumor initiation ability in vivo. Downregulation of NEDD8 enhanced the susceptibility of NPC cells to cisplatin and radiation. Moreover, we found that MLN4924 suppressed c-Jun degradation in human NPC cells. Taken together, this report revealed that NEDD8 may act as a novel prognostic marker and MLN4924 may serve as a promising therapeutic target for patients with NPC.

Tumor-derived exosomes contain biologically active proteins and messenger and microRNAs (miRNAs). These particles serve as vehicles of intercellular communication and are emerging mediators of tumorigenesis and immune escape. Here, we isolated 30-100 nm exosomes from the serum of patients with nasopharyngeal carcinoma (NPC) or the supernatant of TW03 cells. Increased circulating exosome concentrations were correlated with advanced lymphoid node stage and poor prognosis in NPC patients (P < 0.05). TW03-derived exosomes impaired T-cell function by inhibiting T-cell proliferation and Th1 and Th17 differentiation and promoting Treg induction by NPC cells in vitro. These results are associated with decreases in ERK, STAT1, and STAT3 phosphorylation and increases in STAT5 phosphorylation in exosome-stimulated T-cells. TW03-derived exosomes increased the proinflammatory cytokines IL-1β, IL-6, and IL-10 but decreased IFNγ, IL-2, and IL-17 release from CD4+ or CD8+ T-cells. Furthermore, five commonly over-expressed miRNAs were identified in the exosomes from patient sera or NPC cells: hsa-miR-24-3p, hsa-miR-891a, hsa-miR-106a-5p, hsa-miR-20a-5p, and hsa-miR-1908. These over-expressed miRNA clusters down-regulated the MARK1 signaling pathway to alter cell proliferation and differentiation. Overall, these observations reveal the clinical relevance and prognostic value of tumor-derived exosomes and identify a unique intercellular mechanism mediated by tumor-derived exosomes to modulate T-cell function in NPC.

Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in southern China and Southeast Asia, with the highest metastasis rate among head and neck cancers. The mechanisms underlying NPC progression remain poorly understood. Genome-wide expression profiling on 18 NPC vs. 18 noncancerous nasopharyngeal tissues together with GeneGo pathway analysis and expression verification in NPC cells and tissues revealed a potential role of urokinase-type plasminogen activator receptor (uPAR) in NPC progression, which has not been investigated in NPC. We then observed that uPAR expression is increased in poorly differentiated, highly metastatic NPC cells compared with lowly metastatic cells or differentiated NPC cells. In vitro studies demonstrated that uPAR regulates NPC cell growth, colony formation, migration, and invasion and promotes the epithelial–mesenchymal transition (EMT). Additional tumor xenograft and spontaneous metastasis experiments revealed that uPAR promotes NPC cell growth and metastasis in vivo. The JAK–STAT pathway is involved in uPAR-regulated signaling in NPC cells as determined by immunoblotting. Moreover, uPAR-mediated growth and motility is partially abolished upon treatment with the Jak1/Jak2 inhibitor INCB018424. We suppressed uPA expression in uPAR-overexpressing NPC cells and found that uPAR-mediated cellular growth and motility is not exclusively dependent on uPA. In summary, uPAR is a significant regulator of NPC progression and could serve as a promising therapeutic target.

Radiation and cisplatin-based chemotherapy are major treatments for nasopharyngeal carcinoma (NPC). However, a major impediment for further improving the cure rate is the development of treatment resistance with an undetermined molecular mechanism in metastatic NPC cells. Our established, highly metastatic NPC cells have been reported to be more resistant to cisplatin chemotherapy. In the present study, we found that Ras association domain family member 6 (RASSF6) was downregulated in highly metastatic cells but upregulated in low metastatic cells in comparison to their parental cell line. Ectopic-expression of RASSF6 enhanced the sensitivity of highly metastatic NPC cells to cisplatin or radiation by enhancing apoptosis. RASSF6 depletion conversely reduced treatment sensitivity by decreasing the apoptosis rate. Over-expression of RASSF6 in highly metastatic NPC cells could enhance the phosphorylation of JNK when exposed to cisplatin or radiation treatment, while knocking down RASSF6 in low metastatic NPC cells could reduce the level of phospho-JNK when exposed to the same treatments. The activation of JNK signaling by RASSF6 and its subsequent sensitivity to apoptosis in NPC cells could be inhibited by applying the JNK inhibitor SP600125. In conclusion, the downregulation of RASSF6 in highly metastatic NPC cells contributed to their treatment resistance, and over-expression of RASSF6 conferred treatment sensitivity to highly metastatic NPC cells by activating JNK signaling. RASSF6 could be a valuable molecular marker for identifying sensitive metastatic NPC tumors during cisplatin treatment or radiotherapy.

A replication-deficient adenovirus (Ad) encoding secreted human endostatin (Ad-Endo) has been demonstrated to have promising antiangiogenic and antitumoral effects. The E1B55k-deleted Ad H101 can selectively lyse cancer cells. In this study, we explored the antitumor effects and cross-interactions of Ad-Endo and H101 on nasopharyngeal carcinoma (NPC). The results showed that H101 dramatically promoted endostatin expression by Ad-Endo via rescuing Ad-Endo replication in NPC cells, and the expressed endostatin proteins significantly inhibited the proliferation of human umbilical vein endothelial cells. E1A and E1B19k products are required for the rescuing of H101 to Ad-Endo replication in CNE-1 and CNE-2 cells, but not in C666-1 cells. On the other hand, Ad-Endo enhanced the cytotoxicity of H101 by enhancing Ad replication in NPC cells. The combination of H101 and Ad-Endo significantly inhibited CNE-2 xenografts growth through the increased endostatin expression and Ad replication. These findings indicate that the combination of Ad-Endo gene therapy and oncolytic Ad therapeutics could be promising in comprehensive treatment of NPC.

Dicer11 plays an important role in generation of microRNA and is dysregulated in a variety of human cancers. The purpose of this study was to evaluate Dicer11 expression and its prognostic value in nasopharyngeal carcinoma (NPC). The protein expression of Dicer1 was examined by immunohistochemistry in 276 NPC specimens, and the mRNA levels of Dicer1 were analyzed by qRT-PCR in 56 NPC and 11 nasopharyngitis tissues. Cox regression analysis was used to identify independent prognostic factors, and a prognostic score model was constructed for survival prediction. Expression of Dicer1 was downregulated in NPC tissues at both the mRNA and the protein levels, and there was a notable positive correlation between the expression levels of Dicer1 mRNA and protein. Low Dicer1 expression was positively correlated with distant metastasis (P

Approximately 30% of patients with Epstein-Barr virus (EBV)-positive advanced nasopharyngeal carcinoma (NPC) display chemoresistance to cisplatin-based regimens, but the underlying mechanisms are unclear. The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1), a functional homologue of the tumor necrosis factor receptor family, contributes substantially to the oncogenic potential of EBV through the activation of multiple signaling pathways, and it is closely associated with a poorer prognosis for NPC. Recent studies show that EBV infection can induce the expression of many cellular miRNAs, including microRNA-21, a biomarker for chemoresistance. However, neither a link between LMP1 expression and miR-21 upregulation nor their cross talk in affecting chemoresistance to cisplatin have been reported. Here, we observed that stable LMP1-transformed NPC cells were less sensitive to cisplatin treatment based on their proliferation, colony formation, the IC50 value of cisplatin and the apoptosis index. Higher levels of miR-21 were found in EBV-carrying and LMP1-positive cell lines, suggesting that LMP1 may be linked to miR-21 upregulation. These data were confirmed by our results that exogenous LMP1 increased miR-21 in both transiently and stably LMP1-transfected cells, and the knock down of miR-21 substantially reversed the resistance of the NPC cells to cisplatin treatment. Moreover, the proapoptotic factors programmed cell death 4 (PDCD4) and Fas ligand (Fas-L), which were negatively regulated by miR-21, were found to play an important role in the program of LMP1-dependent cisplatin resistance. Finally, we demonstrated that LMP1 induced miR-21 expression primarily by modulating the PI3K/AKT/FOXO3a signaling pathway. Taken together, we revealed for the first time that viral LMP1 triggers the PI3K/Akt/FOXO3a pathway to induce human miR-21 expression, which subsequently decreases the expression of PDCD4 and Fas-L, and results in chemoresistance in NPC cells.

Serglycin is a proteoglycan that was first found to be secreted by hematopoietic cells. As an extracellular matrix (ECM) component, serglycin promotes nasopharyngeal carcinoma (NPC) metastasis and serves as an independent, unfavorable NPC prognostic indicator. The detailed mechanism underlying the roles of serglycin in cancer progression remains to be clarified. Here, we report that serglycin knockdown in NPC cells inhibited cell sphere formation and tumor seeding abilities. Serglycin downregulation enhanced high-metastasis NPC cell sensitivity to chemotherapy. It has been reported that serglycin is a novel ligand for the stem cell marker CD44. Interestingly, we found a positive correlation between serglycin expression and CD44 in nasopharyngeal tissues and NPC cell lines. Further study revealed that CD44 was an ERK-dependent downstream effector of serglycin signaling, and serglycin activated the MAPK/β-catenin axis to induce CD44 receptor expression in a positive feedback loop. Taken together, our novel findings suggest that ECM serglycin upregulated CD44 receptor expression to maintain NPC stemness by interacting with CD44 and activating the MAPK/β-catenin pathway, resulting in NPC cell chemoresistance. These findings suggest that the intervention of serglycin/CD44 axis and downstream signaling pathway is a rational strategy for targeting NPC cancer stem cell therapy.

Our previous study reported that Epstein-Barr virus(EBV)-encoded latent membrane protein 1 (LMP1) could induce development of CD44+/High stem-like cells in nasopharyngeal carcinoma (NPC). However, the molecular mechanisms that underlie modulation of cancer stem cells (CSCs) in NPC remain unclear. Here, we show that LMP1 induced CSC-like properties through promotion of the expression of epithelial-mesenchymal transition (EMT)-like cellular markers and through alterations in differentiation markers. Furthermore, LMP1 activated and triggered PI3K/AKT pathway, which subsequently stimulated expression of CSC markers, development of side population (SP) and tumor sphere formation. This suggests that PI3K/AKT pathway plays an important role in the induction and maintenance of CSC properties in NPC. Similarly, PI3K/AKT pathway was also activated by phosphorylase in LMP1-induced CD44+/High cells. In addition, LMP1 greatly increased expression of miR-21 and down-regulated expression of the miR-21 target, PTEN. Overexpression of miR-21 by transfection of miR-21 mimics into LMP1-transformed cells led to phosphorylase-mediated activation of the PI3K/AKT pathway and induction of CSCs. On the contrary, phosphorylation of the PI3K/AKT pathway and the expression of CSC were reversed by a miR-21 inhibitor. The specific inhibitor (Ly294002) of PI3K/AKT pathway significantly decreased expression of miR-21 and CSC markers and up-regulated the expression of PTEN, which indicates that miR-21 and PTEN are the downstream effectors of PI3K/AKT and that expression of these two effectors are related to development of NPC CSCs. Taken together, our novel findings indicate that LMP1, PI3K/AKT, miR-21 and PTEN constitute a positive feedback loop and play a key role in LMP1-induced CSCs in NPC. Citation Format: Chang-Fu Yang, Guang-Da Yang, Tie-Jun Huang, Jia-Ling Huang, Chao-Nan Qian, Bi-Jun Huang. EB-virus latent membrane protein 1 potentiates the stemness of nasopharyngealcarcinoma via preferential activation of PI3K/AKT pathway by a positive feedback loop. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3360.

Objectives: The role of heparanase (HPSE) gene in cancers including hepatocellular carcinoma (HCC) is currently controversial. This study was aimed at investigating the impact of genetic alteration and expression change of HPSE on the progression and prognosis of HCC. Methods: The HPSE gene was studied in three different aspects: (1) loss of heterozygosity (LOH) by a custom SNP microarray and DNA copy number by real-time PCR; (2) mRNA level by qRT-PCR; and (3) protein expression by immunohistochemistry. The clinical significances of allele loss and expression change of HPSE were analyzed. Results: Microarray analysis showed that the average LOH frequency for 10 SNPs located within HPSE gene was 31.6%, three of which were significantly correlated with tumor grade, serum HBV-DNA level, and AFP concentration. In agreement with SNP LOH data, DNA copy number loss of HPSE was observed in 38.74% (43/111) of HCC cases. HPSE mRNA level was notably reduced in 74.1% (83/112) of tumor tissues compared with non-tumor liver tissues, which was significantly associated with DNA copy number loss, increased tumor size, and post-operative metastasis. HPSE protein level was also remarkably reduced in 66.3% (53/80) of tumor tissues, which was correlated with tumor grade. Patients with lower expression level of HPSE mRNA or protein had a significantly lower survival rate than those with higher expression. Cox regression analysis suggested that HPSE protein was an independent predictor of overall survival in HCC patients. Conclusions: The results in this study demonstrate that genetic alteration and reduction of HPSE expression are associated with tumor progression and poor prognosis of HCCs, suggesting that HPSE behaves like a tumor suppressor gene and is a potential prognostic marker for HCC patients. Citation: Huang G-L, Li B-K, Zhang M-Y, Wei R-R, Yuan Y-F, et al. (2012) Allele Loss and Down-Regulation of Heparanase Gene Are Associated with the Progression

Background Breast cancer metastasis suppressor 1 (BRMS1) is a metastasis suppressor gene. This study aimed to investigate the impact of BRMS1 on metastasis in nasopharyngeal carcinoma (NPC) and to evaluate the prognostic significance of BRMS1 in NPC patients. Methods BRMS1 expression was examined in NPC cell lines using quantitative reverse transcription-polymerase chain reaction and Western blotting. NPC cells stably expressing BRMS1 were used to perform wound healing and invasion assays in vitro and a murine xenograft assay in vivo. Immunohistochemical staining was performed in 274 paraffin-embedded NPC specimens divided into a training set (n = 120) and a testing set (n = 154). Results BRMS1 expression was down-regulated in NPC cell lines. Overexpression of BRMS1 significantly reversed the metastatic phenotype of NPC cells in vitro and in vivo. Importantly, low BRMS1 expression was associated with poor distant metastasis-free survival (DMFS, P P Conclusions Low expression of the metastasis suppressor BRMS1 may be an independent prognostic factor for poor prognosis in NPC patients.

Interferon gamma (IFNgamma) is regarded as a potent antitumor agent, but therapy with IFNgamma is hampered by its short half-life and significant side effects. We developed a replication defective adenovirus carrying the human IFNgamma gene and evaluated the effects of adenovirus-mediated IFNgamma (Ad-IFNgamma) gene transfer on human prostate cancer cell lines in vitro and on xenografts in vivo. Our results showed infection of prostate cancer cells with Ad-IFNgamma led to production of an active cytokine and resulted in an antiproliferative effect on the prostate cancer cells. Intratumoral injection of Ad-IFNgamma significantly inhibited the growth of DU-145 cell xenografts in vivo, while no significant toxicity effect was observed. RT-PCR analysis indicated transgene expression mainly enriched in tumors in vivo, and slightly distributed in livers. These findings suggest adenovirus-mediated IFNgamma gene transfer is a promising approach in the treatment of advanced prostate cancer.

To determine the accuracy of p53 gene mutations predicted by overexpression of p53 protein immunohistochemically, and to investigate the co-mutation of p53 and K-ras genes in rectal cancer and its effect on promoting malignant biologic behaviors of tumors.Ninety-seven specimens of rectal cancer were surgically resected in our hospital from August 1996 to October 1997. The hot mutation areas of p53 gene (in exons 5-8) and K-ras gene (in codon 5/12 and 13) were detected with polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), and overexpression of p53 protein was detected with immunohistochemistry (IHC) in the 97 specimens of rectal cancer. Correlation between gene mutations and tumor clinicopathologic factors was studied, and survival analysis was penfomed as well.There were 36 cases of p53 gene mutations in 61 p53 protein positive cases, and 21 cases of p53 gene non-mutation in 36 p53 protein negative cases respectively. The coincidence rate of p53 gene mutation by IHC method with PCR-SSCP method was 58.8% (57/97). The mutation rate of p53 gene was 52.6% (51/97), while K-ras gene mutation was observed in codons 12 and 13 in 61 cases with a mutation rate of 62.9% (61/97). Single gene mutation of p53 or K-ras was found in 32 cases. Both p53 and K-ras gene mutation were found in 48 cases. Statistical analysis showed that p53 and K-ras gene mutations were not related to the clinicopathologic factors, including tumor size, gross tumor type, histological classification, differentiation, invasion to intestinal veins, lymphatics and nerves, invasive depth to wall, lymph node metastasis, and Dukes' stages (P0.05). The survival in patients with no gene mutation, single gene mutation and both gene mutations were similar (P0.05).IHC has a certain false positive and false negative rate in detecting p53 gene mutations. Malignant biological behaviours of rectal cancer are not enhanced by p53 and K-ras gene mutations. Co-mutation of p53 and K-ras gene has neither synergic carcinogenesis-promoting effect, nor prognostic effect on rectal cancer.

AIM: To investigate genes around the locus D4S2964 affected by loss of heterozygosity (LOH) and their clinical implications. METHODS: Four hundred and forty single nucleotide polymorphisms (SNPs) located at 49 genes around D4S2964 were selected from the National Center for Biotechnology Information website for the SNPs microarray fabrication. LOH of SNPs markers in 112 cases of hepatocellular carcinoma (HCC) tissues and paired adjacent liver tissues were investigated by the SNPs microarray. The correlation between allelic losses with clinicopathological features and overall survival was analyzed. RESULTS: A fine map of LOH of SNPs in genes around D4S2964 was plotted. The average frequency of LOH in genes was 0.39. A correlation between cirrhosis and the FAL index (fractional allelic loss) was found (P = 0.0202). Larger tumor size was found to be significantly associated with LOH in genes ADP-ribosyltransferase 3 (ART3), nucleoporin 54 kDa (NUP54), scavenger receptor class B, member 2 (SCARB2) and coiled-coil domain containing 158 (CCDC158) (P = 0.043, P = 0.019, P = 0.001, P = 0.037, respectively). Kaplan-Meier analysis showed that patients with LOH in ARD1 homolog B (ARD1B) and septin 11 (SEPT11) had a significantly lower survival rate than those with retention (P = 0.021 and P = 0.004, respectively). A Cox regression model suggested that LOH in ARD1B and SEPT11, respectively, were predictors of the overall survival in HCC (P = 0.006 and P = 0.026, respectively). CONCLUSION: LOH in genes around D4S2964 may play an important role in HCC development and progression. LOH in ARD1B and SEPT11 could serve as novel prognostic predictors in HCC patients.

Nasopharyngeal carcinoma (NPC) is a common malignancy in Southern China and Southeast Asia. In this study, we investigated the functional and molecular mechanisms by which CDC42-interacting protein 4 (CIP4) influences NPC. The expression levels of CIP4 were examined by Western blot, qRT-PCR or IHC. MTT assay was used to detect the proliferative rate of NPC cells. The invasive abilities were examined by matrigel and transwell assay. The metastatic abilities of NPC cells were revealed in BALB/c nude mice. We report that CIP4 is required for NPC cell motility and invasion. CIP4 promotes the activation of N-WASP that controls invadopodia formation and activates EGFR signaling, which induces downstream MMP2 (matrix metalloproteinase 2) upregulation. In addition, CIP4 could promote NPC metastasis by activating the EGFR pathway. In nude mouse models, distant metastasis was significantly inhibited in CIP4-silenced groups. High CIP4 expression is an independent adverse prognostic factor of overall survival (OS) and distant metastasis-free survival (DMFS). We identify the critical role of CIP4 in metastasis of NPC which suggest that CIP4 may be a potential therapeutic target of NPC patients.