Qingqing Cai

linc-UBC1 physically associates with polycomb repressive complex 2 (PRC2) and acts as a negative prognostic factor for lymph node metastasis and survival in bladder cancer

OBJECTIVES The human genome encodes many long intergenic noncoding RNAs (lincRNAs). However, their biological functions, molecular mechanisms and prognostic values associated with bladder cancer remain to be elucidated. Here we investigated a lincRNA termed linc-UBC1 (Up-regulated in bladder cancer 1) and evaluated its prognostic value in bladder cancer patients. MATERIALS AND METHODS Expression of linc-UBC1 was evaluated by quantitative reverse transcription PCR (qRT-PCR) in 102 bladder cancer tissue samples and normal adjacent tissues. The functions of linc-UBC1 on cell proliferation, migration, invasion, colony formation, tumorigenicity and metastatic potential were evaluated by knockdown strategy in vitro and in vivo. RNA immunoprecipitation (RIP) was performed to confirm that linc-UBC1 physically associates with EZH2 and SUZ12, core components of polycomb repressive complex 2 (PRC2). Chromatin immunoprecipitation (ChIP) was conducted to examine histone modification status. RESULTS qRT-PCR confirmed that linc-UBC1 expression is up-regulated in 60 cases (58.8%) in bladder cancer tissues compared with normal adjacent tissues, and its overexpression correlates with lymph node metastasis and poor survival. Further functional analysis demonstrated that knockdown of linc-UBC1 attenuates bladder cancer cell proliferation, motility, invasion, colony formation ability, tumorigenicity and metastatic potential. Importantly, the inhibitory effect of linc-UBC1 on cell proliferation was also observed in primary bladder cancer cells obtained from patients. RIP and ChIP assay confirmed that linc-UBC1 physically associates with PRC2 complex and regulates histone modification status of target genes. CONCLUSIONS Frequently overexpressed linc-UBC1 physically associates with PRC2 complex, and acts as a negative prognostic factor for lymph node metastasis and survival in bladder cancer.

Long-term outcomes of patients with newly diagnosed extranodal natural killer/T-cell lymphoma treated by etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin regimen: a single-institution experience

One possible reason for the relapse and refractoriness of extranodal natural killer/T-cell (NK/T) lymphoma (ENKL) is resistance to a CHOP-like regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone). To evaluate the outcome of first-line EPOCH chemotherapy (etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin) for ENKL, 34 patients, including 30 with nasal ENKL (88.2%) and four with extranasal ENKL (11.8%), were studied. Involved-field radiation therapy (IFRT) was administered to patients with localized nasal focus after chemotherapy. Thirty-three cases were eligible for response evaluation. The response rate (RR) was 60.6% (20/33) with a complete remission (CR) rate of 45.5% (15/33). For patients with localized nasal ENKL, the CR rate was 57.7% (15/26). The 3-year progression-free survival and overall survival rates were 53.6% and 69.0%, respectively. After initial EPOCH chemotherapy followed by IFRT, the CR rate was 75.0% and the 3-year overall survival rate was 75.0%. However, patients with disseminated and extranasal disease responded poorly. These results indicate that EPOCH followed by IFRT yields promising outcomes for patients with localized nasal ENKL.

Upregulated WDR5 promotes proliferation, self-renewal and chemoresistance in bladder cancer via mediating H3K4 trimethylation

WD repeat domain 5 (WDR5) plays an important role in various biological functions through the epigenetic regulation of gene transcription; however, its role in bladder cancer remains largely unknown. Our study investigated the role of WDR5 in bladder cancer and demonstrated that WDR5 was upregulated in bladder cancer tissues, and elevated WDR5 protein levels positively correlated with advanced tumor stage and poor survival. Through gain or loss of function, we demonstrated that WDR5 promoted proliferation, self-renewal and chemoresistance to cisplatin in bladder cancer cells in vitro, and tumor growth in vivo. Mechanistically, WDR5 regulated various functions in bladder cancer by mediating the transcription of cyclin B1, cyclin E1, cyclin E2, UHMK1, MCL1, BIRC3 and Nanog by histone H3 lysine 4 trimethylation. Therefore, we have discovered that WDR5 plays an important role in bladder cancer suggesting that WDR5 is a potential biomarker and a promising target in the treatment of bladder cancer.

Vitamin Intake Reduce the Risk of Gastric Cancer: Meta-Analysis and Systematic Review of Randomized and Observational Studies

Aim The association between vitamin intake and gastric cancer (GC) has been widely debated due to the relatively weak evidence. In this study, a meta-analysis of prospective and well designed observational studies were performed to explore this association. Methods MEDLINE, Cochrane Library, and Sciencedirect were searched for studies of vitamin consumption and gastric cancer. This produced 47 relevant studies covering 1,221,392 human subjects. Random effects models were used to estimate summary relative risk (RR). Dose-response, subgroup, sensitivity, meta-regression, and publication bias analyses were conducted. Results The RR of gastric cancer in the group with the highest vitamin intake was compared to that of the lowest intake group. Total vitamin intake was 0.78 (95% CI, 0.71−0.83). In 9 studies that individuals were given doses at least 4 times above the tolerable upper intake (UL) vitamins, the RR was 1.20 (95% CI, 0.99−1.44). However, in 17 studies that individuals received doses below the UL, the RR was 0.76 (95% CI, 0.68−0.86). Dose-response analysis was conducted on different increments in different types of vitamins (vitamin A: 1.5 mg/day, vitamin C: 100 mg/day, vitamin E: 10 mg/day) intake with a significant reduction in the risk of gastric cancer, respectively, 29% in vitamin A, 26% in vitamin C, and 24% in vitamin E. Conclusion This meta-analysis clearly demonstrated that low doses of vitamins can significantly reduce the risk of GC, especially vitamin A, vitamin C, vitamin E.

MicroRNA-374b Suppresses Proliferation and Promotes Apoptosis in T-cell Lymphoblastic Lymphoma by Repressing AKT1 and Wnt-16

Purpose: Deregulation of microRNA (miRNA) has been extensively investigated in both Hodgkin and non-Hodgkin lymphomas (NHL); however, little is known about the roles of miRNAs in T-cell lymphoblastic lymphoma (T-LBL). The aim of the present study was to investigate the potential roles of miR-374b in the development and treatment of T-LBL. Experimental Design: MiRCURY LNA array was used to generate a miRNA-expressing profile. Real-time quantitative PCR and immunohistochemistry (IHC) were applied to detect the expression of miR-374b, AKT1, and Wnt16 in T-LBL samples. The dual-luciferase reporter assay was conducted to confirm target associations of miR-374b. The tumor-suppressive effect of miR-374b was determined by both in vitro and in vivo studies. Results: The expression of 380 miRNAs was evaluated in five human T-LBL tissues and five infantile thymus samples by microRNA microarrays. Downregulation of miR-374b was frequently detected in primary T-LBL tissues, which was significantly associated with worse overall survival and increased risk of recurrence of the 58 patients enrolled in this study. miR-374b suppressed T-LBL cell proliferation in vitro and in vivo and sensitized cells to serum starvation- and chemotherapeutic agent-induced apoptosis. Furthermore, we characterized two AKT pathway–associated molecules, AKT1 and Wnt16, as direct targets of miR-374b. Consistently, in T-LBL patient tissues, AKT1 and Wnt16 expression was inversely correlated with miR-374b levels, and was an independent predictor of recurrence and survival. Conclusions: Our data highlight the molecular etiology and clinical significance of miR-374b in T-LBL. Targeting miR-374b may represent a new therapeutic strategy to improve therapy and survival for T-LBL patients. Clin Cancer Res; 21(21); 4881–91. ©2015 AACR.

13-methyltetradecanoic acid exhibits anti-tumor activity on T-cell lymphomas in vitro and in vivo by down-regulating p-AKT and activating caspase-3.

13-Methyltetradecanoic acid (13-MTD), a saturated branched-chain fatty acid purified from soy fermentation products, induces apoptosis in human cancer cells. We investigated the inhibitory effects and mechanism of action of 13-MTD on T-cell non-Hodgkin’s lymphoma (T-NHL) cell lines both in vitro and in vivo. Growth inhibition in response to 13-MTD was evaluated by the cell counting kit-8 (CCK-8) assay in three T-NHL cell lines (Jurkat, Hut78, EL4 cells). Flow cytometry analyses were used to monitor the cell cycle and apoptosis. Proteins involved in 13-MTD-induced apoptosis were examined in Jurkat cells by western blotting. We found that 13-MTD inhibited proliferation and induced the apoptosis of T-NHL cell lines. 13-MTD treatment also induced a concentration-dependent arrest of Jurkat cells in the G1-phase. During 13-MTD-induced apoptosis in Jurkat cells, the cleavage of caspase-3 and poly ADP-ribose polymerase (PARP, a caspase enzymolysis product) were detected after incubation for 2 h, and increased after extending the incubation time. However, there was no change in the expression of Bcl-2 or c-myc proteins. The appearance of apoptotic Jurkat cells was accompanied by the inhibition of AKT and nuclear factor-kappa B (NF-κB) phosphorylation. In addition, 13-MTD could also effectively inhibit the growth of T-NHL tumors in vivo in a xenograft model. The tumor inhibition rate in the experimental group was 40%. These data indicate that 13-MTD inhibits proliferation and induces apoptosis through the down-regulation of AKT phosphorylation followed by caspase activation, which may provide a new approach for treating T-cell lymphomas.

Fasting blood glucose is a novel prognostic indicator for extranodal natural killer/T-cell lymphoma, nasal type

Background:Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL) is an aggressive disease with poor prognosis, requiring risk stratification. However, the prognosis of ENKTL is not fully defined and needs supplementation. We hypothesised that fasting blood glucose (FBG) may be a new prognostic factor for ENKTL.Methods:We retrospectively analysed 130 patients newly diagnosed with ENKTL.Results:Both univariate analysis and multivariate analysis revealed that FBG >100 mg dl−1 was associated with a poor outcome. Patients with FBG >100 mg dl−1 at diagnosis had more adverse clinical features, achieved lower complete remission rates (P=0.003) and had worse overall survival (P<0.001) and progression-free survival (P<0.001) compared with low-FBG patients. Measurement of FBG was helpful in differentiating between low-risk patients using the International Prognostic Index (IPI) and Prognosis Index for peripheral T-cell lymphoma (PIT) scoring and patients in a different category using the Korean Prognostic Index (KPI) scores with different survival outcomes (P<0.05).Conclusion:Our data suggest that measuring FBG levels at diagnosis is a novel, independent predictor of prognosis in ENKTL and helps to distinguish low-risk patients with poor survival, and this holds true in patients considered low-risk by IPI, PIT and KPI.

An NKX3.1 binding site polymorphism in the l-plastin promoter leads to differential gene expression in human prostate cancer

The L‐plastin gene is involved in the invasion and metastasis of prostate cancer. However, the molecular mechanisms underlying L‐plastin transcription are unclear. We hypothesize that the occurrence of polymorphic genetic variations in the L‐plastin promoter might affect an individuals susceptibility to prostate cancer. In this study, we identified a single nucleotide polymorphism (SNP) at position −1,687 in the L‐plastin promoter by genotype sequencing. The SNP −1,687 showed different transcriptional activity in the luciferase assay in vitro. The TRANSFAC software was applied to predict the multiple cis‐elements, and luciferase assay was used to further identify the L‐plastin regulatory region. We performed EMSAs, supershift assays and ChIP‐qPCR demonstrated that the transcriptional suppressor NKX3.1 binds to the SNP site of the L‐plastin promoter. SNP −1,687 (T/T) led to an increase in the affinity of NKX3.1 for L‐plastin promoter, resulted in lower levels of L‐plastin RNA and protein expression. Furthermore, we collected and sequenced samples from 640 individuals (372 prostate cancer patients and 268 healthy controls) from 2000 to 2013. The results showed that SNP −1,687 (T/T) occurred more frequently in the healthy individuals than that in the prostate cancer patients compared to SNP −1,687 (C/C). Similarly, SNP −1,687 (T/T) genotype occurred more frequently compared to SNP −1,687 (C/C) genotype in the patients with low and moderately differentiated tumors. In conclusion, SNP −1,687, located in the NKX3.1 binding site within the L‐plastin promoter, might reduce the expression of L‐plastin and potentially decrease the tumorigenesis and progression of prostate cancer. This SNP could be a potential prognostic factor for prostate cancer.

A Genomic-clinicopathologic Nomogram for the Preoperative Prediction of Lymph Node Metastasis in Bladder Cancer

Preoperative lymph node (LN) status is important for the treatment of bladder cancer (BCa). Here, we report a genomic-clinicopathologic nomogram for preoperatively predicting LN metastasis in BCa. In the discovery stage, 325 BCa patients from TCGA were involved and LN-status-related mRNAs were selected. In the training stage, multivariate logistic regression analysis was used to developed a genomic-clinicopathologic nomogram for preoperative LN metastasis prediction in the training set (SYSMH set, n = 178). In the validation stage, we validated the nomogram using two independent sample sets (SYSUCC set, n = 142; RJH set, n = 104) with respect to its discrimination, calibration and clinical usefulness. As results, we identified five LN-status-related mRNAs, including ADRA1D, COL10A1, DKK2, HIST2H3D and MMP11. Then, a genomic classifier was developed to classify patients into high- and low-risk groups in the training set. Furthermore, a nomogram incorporating the five-mRNA-based classifier, image-based LN status, transurethral resection (TUR) T stage, and TUR lymphovascular invasion (LVI) was constructed in the training set, which performed well in the training and validation sets. Decision curve analysis demonstrated the clinical value of our nomogram. Thus, our genomic-clinicopathologic nomogram shows favorable discriminatory ability and may aid in clinical decision-making, especially for cN-patients.

The Effect of Prophylactic Lamivudine plus Adefovir Therapy Compared with Lamivudine Alone in Preventing Hepatitis B Reactivation in Lymphoma Patients with High Baseline HBV DNA during Chemotherapy

Prophylactic antiviral therapy is essential for lymphoma patients with high baseline HBV DNA who undergo cytotoxic chemotherapy. However, there are limited data on the optimal options. The present study was designed to compare the efficacy of prophylactic lamivudine (LAM) with lamivudine plus adefovir dipivoxil (LAM+ADV) in preventing hepatitis B virus (HBV) reactivation in lymphoma with, pre-chemotherapy HBV DNA load ≥2000 IU/ml. We retrospectively analyzed the medical records of 86 lymphoma patients with baseline HBV DNA load ≥2000 IU/ml during chemotherapy and received LAM or LAM+ADV as prophylaxis between January 1, 2008 and November 30, 2014 at Sun Yat-sen University Cancer Center, China. Sixty-five patients received LAM and 21 received LAM+ADV. The rate was significantly lower in the LAM+ADV group compared with the LAM group for HBV reactivation (23.8% vs 55.4%; p = 0.012), while no difference was observed between the two groups in patients for HBV-related hepatitis (21.3% vs 33.3%; p   =  0.349), and chemotherapy disruption (10.9% vs 19.0%; p = 0.337). In a multivariate analysis of factors associated with HBV reactivation in these patients, LAM+ADV treatment and HBeAg negative were the independent protective factors. Therefore, LAM+ADV should be considered for antiviral prophylaxis in lymphoma patients with pre-chemotherapy HBV DNA load ≥2000 IU/ml. Further study is warranted to confirm these findings.