TSPAN1 inhibits metastasis of nasopharyngeal carcinoma via suppressing NF-kB signaling

Nasopharyngeal carcinoma (NPC) originates in the epithelial cells of the nasopharynx and is a common malignant tumor in southern China and Southeast Asia. Metastasis of NPC remains the main cause of death for NPC patients even though the tumor is sensitive to radiotherapy and chemotherapy. Here, we found that the transmembrane protein tetraspanin1 (TSPAN1) potently inhibited the in vitro migration and invasion, as well as, the in vivo metastasis of NPC cells via interacting with the IKBB protein. In addition, TSPAN1 was essential in preventing the overactivation of the NF-kB pathway in TSPAN1 overexpressing NPC cells. Furthermore, reduced TSPAN1 expression was associated with NPC metastasis and the poor prognosis of NPC patients. These results uncovered the suppressive role of TSPAN1 against NF-kB signaling in NPC cells for preventing NPC metastasis. Its therapeutic value warrants further investigation.

Ulinastatin inhibits the metastasis of nasopharyngeal carcinoma by involving uPA/uPAR signaling

Distant metastasis is the primary reason for treatment failure in patients with nasopharyngeal carcinoma (NPC). In this study, we investigated the effect of ulinastatin (UTI) on NPC metastasis and its underlying mechanism. Highly-metastatic NPC cell lines S18 and 58F were treated with UTI and the effect on cell proliferation, migration, and invasion were determined by MTS and Transwell assays. S18 cells with luciferase-expressing (S18-1C3) were injected into the left hind footpad of nude mice to establish a model of spontaneous metastasis from the footpad to popliteal lymph node (LN). The luciferase messenger RNA (mRNA) was measured by quantitative polymerase chain reaction (qPCR), and the metastasis inhibition rate was calculated. Key molecular members of the UTI-related uPA, uPAR, and JAT/STAT3 signaling pathways were detected by qPCR and immunoblotting. UTI suppressed the migration and infiltration of S18 and 5-8F cells and suppressed the metastasis of S18 cells in vivo without affecting cell proliferation. uPAR expression decreased from 24 to 48 h after UTI treatment. The antimetastatic effect of UTI is partly due to the suppression of uPA and uPAR. UTI partially suppresses NPC metastasis by downregulating the expression of uPA and uPAR.

[Analysis of distribution characteristics of specific immunoglobulin E in 8 092 children with eczema and urticaria in a hospital of pediatric in Tianjin City]

To investigate the common specific immunoglobulin E(sIgE) in children with eczema and urticaria, compare the allergies in children with different diseases, genders and ages, and provide the scientific basis for the prevention, diagnosis and treatment. A retrospective study was conducted to analyze the children who were suspected of eczema and urticaria and tested for serum sIgE in the Tianjin Children's Hospital from December 2019 to August 2021. A total of 8 092 serum samples were tested for ten food allergens and ten inhaled allergens. The method was the enzyme-linked immune capture assay. The allergen epidemiological characteristics were statistically analyzed by Chi square test based on the children's characteristics and factors such as different sexes and ages and by the mass data. The results showed that the positive rate of eczema was 64.42%(5 213/8 092), and the urticaria was 35.58%(2 879/8 092). The positive rate of specific IgE was 66.65%(5 393/8 092), the food allergens was 61.74%(4 996/8 092), and the inhaled allergens was 34.85%(2 820/8 092). The top three positive rates of food allergens were egg 46.65%(3 775/8 092), milk 32.64%(2 641/8 092) and wheat flour 15.08%(1 220/8 092). The top three positive rates of inhaled allergens were house dust 21.40%(1 732/8 092), Alternaria 11.78%(953/8 092) and Dermatophagoides farinae 7.33%(593/8 092). The positivity of food allergens and inhaled allergens was significantly different in different age groups. The positive rates of food allergens in different age groups were 48.92%(947/1 936) in<1 year old, 72.28%(2 680/3 708) in 1-3 years old, 64.58%(919/1 423) in 4-6 years old and 43.90%(450/1 025) in>6 years old. The positive rates of inhaled allergens in different age groups were 17.67%(342/1 936) in<1 year old, 36.35%(1 348/3 708) in 1-3 years old, 46.38%(660/1 423) in 4-6 years old and 45.85%(470/1 025) in>6 years old. The top six positive rates of allergens of eczema were the same with urticaria, which were egg, milk, house dust, wheat flour, Alternaria and Dermatophagoides farinae. The allergens (greater than or equal to grade 4) differed in children with eczema and urticaria. Moreover, there were significant differences in the positive rates of Alternaria, egg, wheat flour, crab and shrimp. In conclusion, this study can reflect the epidemic characteristics of allergens in children with eczema and urticaria to a certain extent. There were significant differences in the positive rates of allergens between different age groups. It is necessary to reasonably avoid the high-risk allergens according to the epidemiological characteristics and clinical symptoms, which provide valuable information for the prevention, diagnosis and treatment of allergic diseases.

Correlated with better prognosis, CSTA inhibits metastasis of nasopharyngeal carcinoma cells via suppressing AKT signaling through promoting METTL3 degradation

BACKGROUND

Metastasis is one of the main obstacles impeding the survival of nasopharyngeal carcinoma (NPC) patients, with the molecular mechanism underlying NPC metastasis still unclear.

RESULTS

In this study, Cystatin A (CSTA) was found downregulated in NPC tissues with metastasis compared with those without metastasis. Shorter overall survival and distant metastasis-free survival were found in NPC patients with lower CSTA expression. Using functional assays, we found that CSTA prevented both the in vitro motility of NPC cells and their ability to metastasize in vivo. Transcriptome sequencing and western blot analysis revealed that CSTA inhibited the phosphorylation of AKT. Moreover, activating AKT using AKT agonist SG79 rescued the motility of CSTA-overexpressing NPC cells, whereas, treatment with AKT inhibitor MK2206 inhibited the motility of CSTA-knockdown NPC cells. Mechanically, immunoprecipitation coupled mass spectrometry found that CSTA interacted with the N6-adenosine-methyltransferase subunit METTL3 and promoted its ubiquitin-proteasome-mediated degradation following the upregulation of NKX3-1 and LHPP, which are negative regulators of AKT. Furthermore, knock-down of NKX3-1 and LHPP enhanced the motility of CSTA-overexpressing NPC cells.

CONCLUSIONS

The inhibitory effect of CSTA upon NPC metastasis mainly depended on suppressing AKT signaling by the upregulation of NKX3-1 and LHPP expression resulting from the binding between CSTA and METLL3. Our study suggests that the CSTA-METLL3-NKX3-1/LHPP-AKT axis could be of therapeutic value for inhibiting NPC metastasis.

Geographical disparities in the prognosis of patients with nasopharyngeal carcinoma treated with intensity-modulated radiation therapy: a large institution-based cohort study from an endemic area

OBJECTIVES

Geographical disparities have been identified as a specific barrier to cancer screening and a cause of worse outcomes for patients with cancer. In the present study, our aim was to assess the influence of geographical disparities on the survival outcomes of patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT).

DESIGN

Cohort study.

SETTING

Guangzhou, China.

PARTICIPANTS

A total of 1002 adult patients with NPC (724 males and 278 females) who were classified by area of residence (rural or urban) received IMRT from 1 January 2010 to 31 December 2014, at Sun Yat-sen University Cancer Center. Following propensity score matching (PSM), 812 patients remained in the analysis.

MAIN OUTCOME MEASURES

We used PSM to reduce the bias of variables associated with treatment effects and outcome prediction. Survival outcomes were estimated using the Kaplan-Meier method and compared by the log-rank test. Multivariate Cox regression was used to identify independent prognostic factors.

RESULTS

In the matched cohort, 812 patients remained in the analysis. Kaplan-Meier survival analysis revealed that the rural group was significantly associated with worse overall survival (OS, p<0.001), disease-free survival (DFS, p<0.001), locoregional relapse-free survival (LRRFS, p=0.003) and distant metastasis-free survival (DMFS, p<0.001). Multivariate Cox regression showed worse OS (HR=3.126; 95% CI 1.902 to 5.138; p<0.001), DFS (HR=2.579; 95% CI 1.815 to 3.665; p<0.001), LRRFS (HR=2.742; 95% CI 1.359 to 5.533; p=0.005) and DMFS (HR=2.461; 95% CI 1.574 to 3.850; p<0.001) for patients residing in rural areas.

CONCLUSIONS

The survival outcomes of patients with NPC who received the same standardised treatment were significantly better in urban regions than in rural regions. By analysing the geographic disparities in outcomes for NPC, we can guide the formulation of healthcare policies.

LACTB promotes metastasis of nasopharyngeal carcinoma via activation of ERBB3/EGFR-ERK signaling resulting in unfavorable patient survival

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.

ETV4 is a theranostic target in clear cell renal cell carcinoma that promotes metastasis by activating the pro-metastatic gene FOSL1 in a PI3K-AKT dependent manner

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.

PTPN3 Inhibits the Growth and Metastasis of Clear Cell Renal Cell Carcinoma via Inhibition of PI3K/AKT Signaling

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-AKT^Thr308 and phospho-AKT^Ser473 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.

Global expression profiling and pathway analysis of mouse mammary tumor reveals strain and stage specific dysregulated pathways in breast cancer progression

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.

Along with its favorable prognostic role, CLCA2 inhibits growth and metastasis of nasopharyngeal carcinoma cells via inhibition of FAK/ERK signaling

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.

PDZ binding kinase (PBK) is a theranostic target for nasopharyngeal carcinoma: driving tumor growth via ROS signaling and correlating with patient survival

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.

A comparison of weekly versus 3-weekly cisplatin during concurrent chemoradiotherapy for locoregionally advanced nasopharyngeal carcinoma using intensity modulated radiation therapy: a matched study

Purpose: To compare the long-term survival outcomes and acute toxicity between locoregionally advanced nasopharyngeal carcinoma (NPC) patients who received either weekly or 3-weekly cisplatin during concurrent chemoradiotherapy (CCRT).

Methods: Between November 2008 and August 2011, 241 biopsy-proved NPC patients receiving concurrent cisplatin with intensity modulated radiotherapy (IMRT) were included. 90 patients treated with 4-7 weeks of 30-40 mg/m² cisplatin weekly were matched with 90 patients who received two or three cycles of 80 mg/m² cisplatin three-weekly by sex, age, T stage, N stage, Karnosky performance score (KPS). IMRT was presented to the nasopharyngeal gross target volume at 66-72 Gy/30-32 fractions and those involved neck area at 60-66 Gy/30-32 fractions.

Results: The median follow-up time was 69 months (range, 2-91 months), and the 5-year overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) rates were 85.6% vs. 90.0% (P = 0.207), 85.6% vs. 92.6% (P = 0.152), 94.4% vs. 96.7% (P = 0.411), and 88.9% vs. 95.6% (P = 0.107) for the group treated weekly and 3-weekly cisplatin, respectively. No statistically significant survival differences were found between the two treatment groups in both univariate and multivariate analyses. The similar incidence of acute toxicities was observed between two groups.

Conclusions: Concurrent cisplatin-based chemotherapy administered weekly or three-weekly in combination with IMRT leads to similar acute toxicities and long-term survival outcomes in locoregionally advanced NPC patients.

The developmental transcription factor IRF6 attenuates ABCG2 gene expression and distinctively reverses stemness phenotype in nasopharyngeal carcinoma

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.

[Effect of goal-directed haemodynamic management on the postoperative outcome in elderly patients with fragile cardiac function undergoing abdominal surgery]

Objective: To investigate the effect of goal-directed haemodynamic management based on stroke volume variation (SVV), cardiac index (CI) and mean arterial blood pressure (MAP) on the postoperative outcome in elderly patients with fragile cardiac function undergoing gastrointestinal surgery. Methods: Ninety patients with fragile cardiac function, aged 65-90 years old, ASAⅡ or Ⅲ, NYHA Ⅱor Ⅲ, scheduled for abdominal surgery were enrolled in this study.The patients were randomly assigned to two groups: Experience anesthesia group (group E, n=45) and goal-directed hemodynamic management group (G group, n=45). After anesthesia induction, in group G, the SVV and CI were monitored by Vigileo and according SVV (≤12%), CI (≥2.5 L·min^-1·m^-2) and MAP (maintain the base value of ±20%) to adjust the preloaded infusion fluid and give positive inotropic drugs and positive pressure drugs; in group E, fluid and vasoactive agent were used according to the experience of anesthesiologist.Multi-mode monitoring anesthesia management using BIS, TCI of propofol, low-tidal-volume lung protective ventilation management strategy, body temperature protection, and postoperative multimodal analgesia techniques was performed in the two groups.Values of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT) were recorded before operation, at the end of operation, and postoperative 24 h. The incidence of myocardial infarction/angina, heart failure, arrhythmia and cerebral infarction, renal failure, length of hospitalization, and complications in 30-days after surgery were recorded by telephone follow-up. Results: Crystal, colloid, total liquid of group E were (1 110.20±332.00), (536.65±72.25), (1 677.20±424.44) ml and these of group G were (708.72±240.85), (414.41±74.31), (878.51±199.13) ml, respectively.Compared with group E, the fluid infusion were reduced in group G (t=6.057, 2.701, 9.742, all P<0.05). The lactic acid value of 24 hours after surgery in group G was significantly lower than that in group E [(0.89±0.31) mmol/L vs (1.11±0.43) mmol/L, t=-2.848, P<0.05]. Arterial partial pressure of oxygen at 24 hours after surgery in group G was higher than that in group E [(78.77±6.86) mmHg vs (76.46±10.96) mmHg, t=-1.108, P<0.05]. The length of hospitalization of group G was shorter than that of group E [(12.21±2.20) d vs (13.16±3.84) d, t=-1.341, P<0.05]. The incidence of total complication in hospital and in 30-days after surgery of group G were 10.26% and 5.13%, while these of group E were 29.73% and 24.32%, (χ²=4.545, 4.520, all P<0.05). ΔNT-proBNP₁ (the base value of NT-proBNP's minus the value of NT-proBNP's at the end of the operation) and ΔNT-proBNP₂ (the base value of NT-proBNP's minus the value of NT-proBNP's 24 hours postoperatively) of group G were 12.0(-291.0, 1 517.0) and 0(-6 770.0, 291.0), both higher than these of group E [0(-440.0, 200.0) and -12.0(-7 200, 22.0), (Z=-2.412, -2.163, all P<0.05)]. Conclusion: Goal-directed haemodynamic management based on SVV, CI and MAP could improve the outcome of the elderly patients with fragile heart function undergoing abdominal surgery.

CDC42-interacting protein 4 promotes metastasis of nasopharyngeal carcinoma by mediating invadopodia formation and activating EGFR signaling

Background

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.

Methods

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.

Results

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).

Conclusion

We identify the critical role of CIP4 in metastasis of NPC which suggest that CIP4 may be a potential therapeutic target of NPC patients.

RNA-binding protein QKI-5 inhibits the proliferation of clear cell renal cell carcinoma via post-transcriptional stabilization of RASA1 mRNA

Clear cell renal cell carcinoma (ccRCC) is a common pathological subtype of renal cancer. Although the recent application of molecular-targeted agents has modestly improved the prognosis of ccRCC patients, their outcome is still poor. It is therefore important to characterize the molecular and biological mechanisms responsible for the development of ccRCC. Approximately 25% ccRCC patients involves the loss of RNA-binding protein QKI at 6q26, but the role of QKI in ccRCC is unknown. Here, we found that QKI-5 was frequently downregulated in ccRCC patients and its down-regulation was significantly associated with clinical features including T status, M status, and differentiation grade, and poorer patient prognosis. Moreover, QKI-5 inhibited the proliferation of kidney cancer cells both in vitro and in vivo. The subsequent functional studies showed that QKI-5 stabilized RASA1 mRNA via directly binding to the QKI response element region of RASA1, which in turn prevented the activation of the Ras-MAPK signaling pathway, suppressed cellular proliferation and induced cell cycle arrest. Overall, our data demonstrate a suppressive role of QKI in ccRCC tumourigenesis that involves the QKI-mediated post-transcriptional regulation of the Ras-MAPK signaling pathway.

SPINK6 Promotes Metastasis of Nasopharyngeal Carcinoma via Binding and Activation of Epithelial Growth Factor Receptor

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.

IL-8 suppresses E-cadherin expression in nasopharyngeal carcinoma cells by enhancing E-cadherin promoter DNA methylation

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.

Downregulation of Ras association domain family member 6 (RASSF6) underlies the treatment resistance of highly metastatic nasopharyngeal carcinoma cells

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.

Urokinase-type plasminogen activator receptor signaling is critical in nasopharyngeal carcinoma cell growth and metastasis

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.

RASSF6 promotes p21(Cip1/Waf1)-dependent cell cycle arrest and apoptosis through activation of the JNK/SAPK pathway in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a highly aggressive and common pathological subtype of renal cancer. This cancer is characterized by biallelic inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene, which leads to the accumulation of hypoxia-inducible factors (HIFs). Although therapies targeted at HIFs can significantly improve survival, nearly all patients with advanced ccRCC eventually succumb to the disease. Thus, additional oncogenic events are thought to be involved in the development of ccRCC tumors. In this study, we investigated the role of RASSF6 in ccRCC. Downregulation of RASSF6 was commonly observed in primary tumors relative to matched adjacent normal tissues. Moreover, functional studies established that ectopic re-expression of RASSF6 in ccRCC cells inhibited cell proliferation, clonogenicity, and tumor growth in mice, whereas silencing of RASSF6 dramatically enhanced cell proliferation in vitro and in vivo. Mechanistic investigation suggested that RASSF6 triggers p21(Cip1/Waf1) accumulation to induce G 1 cell cycle arrest and promote apoptosis upon exposure to pro-apoptotic agents, and both of these mechanisms appear to be mediated by activated JNK signaling. Together, these findings suggest that RASSF6 may play a tumor suppressor role in the progression of ccRCC.

Cancer stem-like cell characteristics induced by EB virus-encoded LMP1 contribute to radioresistance in nasopharyngeal carcinoma by suppressing the p53-mediated apoptosis pathway

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.

Parity Alternation of Ground-State Pn- and Pn+ (n = 3−15) Phosphorus Clusters

The ground-state structures of neutral, cationic, and anionic phosphorus clusters P(n), P(n)(+), and P(n)(-) (n = 3-15) have been calculated using the B3LYP/6-311+G* density functional method. The P(n)(+) and P(n)(-) (n = 3-15) clusters with odd n were found to be more stable than those with even n, and we provide a satisfactory explanation for such trends based on concepts of energy difference, ionization potential, electron affinity, and incremental binding energy. The result of odd/even alternations is in good accord with the relative intensities of cationic and anionic phosphorus clusters observed in mass spectrometric studies.

Observation of two new N* peaks in J/psi-->ppi-n and ppi+n decays

The decay J/psi-->NNpi provides an effective isospin 1/2 filter for the piN system due to isospin conservation. Using 58x10(6) J/psi decays collected with the Beijing Electromagnetic Spectrometer at the Beijing Electron Positron Collider, more than 100 thousand J/psi-->ppi-n+c.c. events are obtained. Besides the two well-known N* peaks at around 1500 MeV/c2 and 1670 MeV/c2, there are two new, clear N* peaks in the ppi invariant mass spectrum around 1360 MeV/c2 and 2030 MeV/c2 with statistical significance of 11sigma and 13sigma, respectively. We identify these as the first direct observation of the N*(1440) peak and a long-sought missing N* peak above 2 GeV/c2 in the piN invariant mass spectrum.

Observation of a threshold enhancement in the plambda invariant-mass spectrum

An enhancement near the m(p)+M(Lambda) mass threshold is observed in the combined pLambda and pLambda invariant-mass spectrum from J/psi-->pK(-)Lambda;+c.c. decays. It can be fit with an S-wave Breit-Wigner resonance with a mass m=2075+/-12(stat)+/-5(syst) MeV and a width of Gamma=90+/-35(stat)+/-9(syst) MeV; it can also be fit with a P-wave Breit-Wigner resonance. Evidence for a similar enhancement is also observed in psi(')-->pK(-)Lambda;+c.c. decays. The analysis is based on samples of 5.8x10(7)J/psi and 1.4x10(7)psi(') decays accumulated in the BES II detector at the Beijing Electron-Positron Collider.

Observation of the decay psi(2S)-->K0SK0L

The decay psi(2S)-->K(0)(S)K(0)(L) is observed using psi(2S) data collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider; the branching fraction is determined to be B(psi(2S)-->K(0)(S)K(0)(L))=(5.24+/-0.47+/-0.48)x10(-5). Compared with J/psi-->K(0)(S)K(0)(L), the psi(2S) branching fraction is enhanced relative to the prediction of the perturbative QCD "12%" rule. The result, together with the branching fractions of psi(2S) decays to other pseudoscalar meson pairs (pi(+)pi(-) and K+K-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.

Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

[Zn8(SiO4)(C8H4O4)6]n: the firstborn of a metallosilicate-organic hybrid material family (C8H4O4 = isophthalate)

[Zn8(SiO4)(C8H4O4)6]n (C8H4O4 = isophthalate), synthesized by hydrothermal reaction, possesses a diamondoid framework structure constructed from hexahedron-like Zn8(SiO4) cores and C8H4O4 linkers and remains stable up to 500 degrees C in air, representing the first member of a new class of metallosilicate-organic hybrid materials.

Separation and identification of perchlorinated polycyclic aromatic hydrocarbons and fullerenes (C60, C70) by coupling high-performance liquid chromatography with ultraviolet absorption spectroscopy and atmospheric pressure chemical ionization mass spectrometry

Simultaneous separation and identification of perchlorinated polycyclic aromatic hydrocarbons (PCPAHs) and fullerenes is of practical interest due to the growth mechanism of fullerenes involved with PCPAHs. Non-aqueous reversed-phase high-performance liquid chromatography (HPLC), with an ODS column and a gradient mobile phase of methanol-ethanol-cyclohexane mixtures, was combined with both rapid-scan ultraviolet spectrometry (UV) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) for the separation and identification of over 80 PCPAHs as well as fullerenes C60 and C70, that were synthesized in the discharge reaction of chloroform. PCPAH retention was found to depend on the number of aromatic rings and the degree of non-planarity of PCPAH structure. Based on the isotopic pattern of molecular ion or/and quasi-molecular ion peaks in corresponding mass spectra, molecular compositions of the PCPAH products were unambiguously determined. The results obtained from the HPLC-UV-MS analysis not only are helpful for the understanding of the fullerenes formation mechanism, but also contribute to the analytical technique capable of separating and identifying the complicated mixture of PCPAHs and fullerenes.

Separation and identification of perchlorinated polycyclic aromatic hydrocarbons by high-performance liquid chromatography and ultraviolet absorption spectroscopy

High-performance liquid chromatography (HPLC) was coupled with ultraviolet absorption spectroscopy (UV) for the simultaneous separation and identification of a series of perchlorinated polycyclic aromatic hydrocarbons, such as perchlorobenzene (C6Cl6), perchloronaphthalene (C10Cl8), perchlorobiphenyl (C12Cl10), perchloroanthracene (C14Cl10), perchlorophenanthrene (C14C10), perchloroacenaphthylene (C12Cl8), perchloropyrene (C16Cl10) and perchlorofluoranthene (C16Cl10). HPLC was performed on an ODS column using methanol-hexane (80:20) as mobile phase at a flow-rate of 1.0 ml/min. UV absorption spectra of the elutes were detected in the region of 210-350 nm.