[The role of human papillomavirus 16 early genes E2 and E6 and heterogeneous nuclear ribonucleoprotein E2 in cervical carcinogenesis and their interaction effect]

Objective: To investigate the role of human papillomavirus (HPV) 16 early genes E2 and E6 and heterogeneous nuclear ribonucleoprotein (hnRNP) E2 and their interaction effects in the progression of the cervical cancer. Methods: Women with normal cervix (NC), low cervical intraepithelial neoplasia (CIN Ⅰ) and high cervical intraepithelial neoplasia (CIN Ⅱ/Ⅲ) from the cervical lesions cohort in Jiexiu County of Shanxi Province from June 2014 to September 2014, and patients with cervical squamous cell carcinoma (SCC) treated at the Second Hospital of Shanxi Medical University in the same period were enrolled in this study. There were 257 participants, about 67 NC cases (26.07%), 69 CIN Ⅰ cases (26.85%), 68 CIN Ⅱ/Ⅲ cases (26.46%), and 53 SCC cases (20.62%), respectively. The information of demographic characteristics, life health habits and cervical lesions were collected by using the structured questionnaire. Cervical exfoliated cells and cervical biopsy tissues were collected to detect the infection of HPV16 and the protein expression levels of hnRNP E2, HPV16 E2 and E6. According to the median-value of the protein expression levels of hnRNP E2, HPV16 E2 and E6 and E2/E6 ratio in the NC group, the study participants were divided into the high and low expression groups/ratio groups. The multivariate logistic regression model was used to analyze the correlation between HPV16 early gene E2 and E6, hnRNP E2 and cervical cancer. The interaction effect was analyzed by using the generalized multifactor dimensionality reduction (GMDR) model. Results: The ages of NC, CIN Ⅰ, CIN Ⅱ/Ⅲ and SCC groups were (47.00±9.07), (47.64±7.35), (46.37±8.67) and (51.26±8.03) years old, respectively. The multivariate logistic regression model analysis showed that the HPV16 E2 low expression, E6 high expression and E2/E6 low ratio could increase the risk of CIN Ⅱ/Ⅲ, about OR (95%CI) values 11.11 (1.63-75.56), 8.00 (1.28-50.04), and 9.75 (1.22-77.72), respectively and SCC, about OR (95%CI) values 14.22 (2.11-95.88), 10.33 (1.67-64.00), and 12.38 (1.56-97.91), respectively. The hnRNP E2 low expression could increase the risk of CIN Ⅱ/Ⅲ and SCC, about OR (95%CI) values 3.35 (1.39-8.10) and 5.53 (1.54-19.88). The result of GMDR showed that there were interaction effects of the hnRNP E2 low expression, HPV16 E2 low expression and HPV16 E6 high expression in both CIN Ⅱ/Ⅲ and SCC groups. Conclusion: The HPV16 E2 low expression, HPV16 E6 high expression and hnRNP E2 low expression could increase the risk of high-grade cervical intraepithelial neoplasia and cervical cancer, and they might have an important interaction effect in the progression of the cervical cancer.

Comparison of Experimental Infection of Normal and Immunosuppressed Chickens with Mycoplasma gallisepticum

Four different models of infection of chickens with Mycoplasma gallisepticum (MG) were evaluated. Normal or immunosuppressed chicks (10 days old) were infected with the MG R_low strain via eye and nasal drops or by direct air sac injection. Bacterial load in the lungs was quantified and air sac and tracheal lesion scores, tracheal mucosal thickness and humoral immune responses were assessed. Serum antibody responses were assessed by use of a serum plate agglutination test. Three days post infection (dpi), all immunosuppressed chicks had developed significant respiratory signs. Chicks infected via air sac injection had significant differences in serum antibody and gross lesion scores at 5 dpi. All chicks had developed pathological changes by 7 dpi. Air sac inoculation of immunosuppressed chicks produced more significant (P ≤0.05) lesions, and these birds had the highest bacterial load in the lungs compared with other groups.

Safety and efficacy of taurine as an add-on treatment for tics in youngsters

BACKGROUND AND PURPOSE

The pathophysiological model of tics generally describes disruption of γ-aminobutyric acid transmission, and taurine is found to be an agonist of γ-aminobutyric acid receptors. The study aimed to evaluate the safety and efficacy of taurine as an add-on treatment for tics.

METHODS

Four hundred and four youngsters with tic disorders were randomly assigned to 12 weeks of either oral taurine or placebo. The Yale Global Tic Severity Scale was used to measure tic severity. The primary outcome measure was global severity scores reduced by more than 60% compared with baseline scores.

RESULTS

Three hundred and eighty-two patients were successfully treated. At week 4, no significant differences were found in the treatment effect and the total occurrence of adverse drug reactions between the taurine and placebo groups. At week 12, the proportion of significant improvement in tics was significantly higher in the taurine group than the placebo group (53.4% with taurine versus 34.5% without taurine; relative risk 1.546; P < 0.001), and no group differences were found in the total occurrence of adverse drug reactions.

CONCLUSIONS

Taurine is safe and effective for tics.

P1616L-2-hydroxyglutarate dehydrogenase (L2HGDH) is a novel target for heart failure due to pressure overload

Background

We have found L-2-hydroxyglutarate dehydrogenase (L2HGDH) to be downregulated in the myocardium of mice subjected to transverse aortic constriction (TAC). L2HGDH is an important regulator of mitochondrial bioenergetics by catalyzing the conversion of L-2-hydroxyglutarate (L2-HG) to α-ketoglutarate. However, the connection between L2-HG accumulation and heart failure is not yet understood.

Purpose

Purpose of our study was to investigate the role of increased L2-HG levels in heart failure and the potential role of L2HGDH overexpression as therapeutic strategy.

Methods

For in vitro studies, primary rat neonatal cardiomyocytes (NRVCMs) were incubated with L2-HG. L2HGDH was overexpressed using adeno-associated virus (AAV) 6 vectors. Mitochondrial membrane potential was measured using TMRE (tetramethylrhodamine ethyl ester) dye. Mitochondrial reactive oxygen species production was monitored using MitoSOX. We further determined activation of fetal gene program by real time qPCR and macrophage migration using RAW 264.7 cells and transwell inserts. mTOR activation was analyzed by Western blot with antibodies against phosphorylated mTOR and ribosomal protein S6. AAV9 expressing L2HGDH or luciferase was injected in C57BL/6N mice two weeks prior to TAC and heart function was monitored by echocardiography for 6 weeks.

Results

L2-HG acts as a pro-hypertrophic stimulus in NRVCMs as shown by upregulation of a fetal gene expression pattern and an increase in cardiomyocyte cross-sectional area upon L2-HG treatment. Furthermore, mRNA levels of macrophage chemoattractant protein 1 were increased in L2-HG treated cells, which correlated with enhanced macrophage migration towards supernatant of L2-HG treated NRVCMs. Furthermore, we could confirm that L2-HG augmented mTOR signaling by affecting the phosphorylation status of ribosomal protein S6. AAV-mediated L2HGDH overexpression in NRVCMs led to a significant 2.1-fold decrease in the accumulation of ROS production. Moreover, we found an inhibition of endothelin-1 induced mitochondrial membrane depolarization in AAV6-L2HGDH transduced cells.

Pretreatment of mice with AAV9-L2HGDH prior to TAC resulted in significantly reduced heart weight to tibia length ratios (HW/TL) and cardiomyocyte area. Importantly, heart function was notably improved in mice receiving gene therapy (ejection fraction, EF: 36.18±6.63%, fractional shortening, FS: 16.72±4.01%) whereas control animals showed marked decline in myocardial contractility (EF: 20.14±8.24%, FS: 12.66±6.66%).

Conclusion

L2-HG causes cardiomyocyte dysfunction by activating mTOR signaling pathway, a well-characterized critical inducer of myocyte hypertrophy, and enhancing macrophage migration, leading to establishment of a pro-inflammatory environment in the myocardium. Moreover, our results point out towards a novel preventive approach for cardiac hypertrophy and heart failure by cardiomyocyte-specific L2HGDH overexpression.

Acknowledgement/Funding

DZHK (Deutsches Zentrum für Herz-Kreislaufforschung)

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

[Effects of hnRNP E1 and both early genes E2 and E6 of HPV16 together with their interactions on cervical carcinogenesis]

Objective: To explore the effects of hnRNP E1 and both early genes E2 and E6 of HPV16 as well as their interactions in the progression of cervical carcinogenesis. Methods: Subjects of this study included 56 women with normal cervix (NC), 58 patients with low-grade cervical intraepithelial neoplasm (CINⅠ) and 50 patients with high-grade cervical intraepithelial neoplasm (CINⅡ/Ⅲ) who were all recruited from the 'Cervical Lesions Study Cohort Project' in Jiexiu of Shanxi province from June to September, 2014. Another 40 patients with cervical squamous cell carcinoma (SCC) were from the Shanxi Tumor Hospital during the same period. Information related to cervical lesions were collected, using a structured questionnaire, with cervical tissues and cervical exfoliated cells gathered from all the participants. HPV infection was detected by flow-through hybridization, while the levels of expression on hnRNP E1, HPV16 E2 and E6 protein were measured by Western Blot. Kruskal-Wallis H test, χ(2) test, trend χ(2) test were analyzed by SPSS 22.0 software, while interaction was evaluated by generalized multifactor dimensionality reduction (GMDR). Results: The overall infection rates of HPV16 related to CINⅠ (15.52%, 9/58), CINⅡ/Ⅲ (40.00%, 20/50) and SCC (67.50%, 27/40) groups were all higher than that of the NC group (8.93%, 5/56) and with an increasing trend on the severity of cervical lesions (trend χ(2)=43.613, P<0.001). The levels of expression on hnRNP E1 protein were significantly different in the groups with different cervical lesions (H=9.98, P=0.019), showing a decreasing trend with the severity of cervical lesions (trend χ(2)=9.495, P=0.002). The levels of expression on HPV16 E2 (H=16.20, P=0.001) and HPV16 E6 (H=15.44, P=0.001) were significantly different in groups with different cervical lesions. Results of GMDR showed that the best interaction model in both groups of CINⅡ/Ⅲ and SCC appeared as hnRNP E1 low expression, HPV16 E2 low expression and HPV16 E6 high expression. However, no similar interaction was seen in CINⅠ (P>0.05). Conclusions: Both low expressions of hnRNP E1 and abnormal expression of HPV16 E2 and E6 could increase the risk of high-grade CIN and cervical cancer. It seemed that they might have an important synergistic effect on the progression of cervical cancer.

[Effects of Src on cervical cancer cells proliferation and apoptosis through ERK signal transduction pathway]

Objective: To explore the effect of Src on cervical cancer cells through ERK signal transduction pathway. Methods: Experimental study was carried out in vitro. Cervical cancer cell lines Hela (HPV-positive) and C33A (HPV-negative) were treated with Src kinase inhibitor PP2. Then, the cell cycle and apoptosis of each group were evaluated by using flow cytometry (FCM). Western blotting and Real-time PCR were used to detect the levels of the expression of ERK 1/2, c-Fos and c-Jun mRNA and protein respectively. The database was established and analyzed with SPSS statistical software (version 20.0). Results: After down-regulating Src, the cell proliferation was inhibited and cell apoptosis was induced. The proportions of G0/G1 stage of Hela and C33A cell in cell cycle increased while G2/M and S stages decreased. Meanwhile, the mRNA levels of ERK 1, ERK 2, c-Fos and c-Jun increased. And the expression levels of ERK 1/2, phosphorylated ERK 1/2 (p-ERK 1/2) and phosphorylated c-Fos (p-c-Fos) protein decreased, while c-Jun and phosphorylated c-Jun (p-c-Jun) protein expression increased. In addtion, the change level of Hela cell, p-ERK 1/2 and c-Fos protein were lower than that of C33A cell before and after the Src inhibition. Conclusions: Src, involved in regulating the expression of key factors of the ERK signal transduction pathway including p-ERK 1/2 and p-c-Fos, might be capable of promoting the proliferation of cervical cancer cells and inhibiting their apoptosis. The infection with HPV might have adjustable effect on this process.

EZH2 cooperates with gain-of-function p53 mutants to promote cancer growth and metastasis

In light of the increasing number of identified cancer-driven gain-of-function (GOF) mutants of p53, it is important to define a common mechanism to systematically target several mutants, rather than developing strategies tailored to inhibit each mutant individually. Here, using RNA immunoprecipitation-sequencing (RIP-seq), we identified the Polycomb-group histone methyltransferase EZH2 as a p53 mRNA-binding protein. EZH2 bound to an internal ribosome entry site (IRES) in the 5'UTR of p53 mRNA and enhanced p53 protein translation in a methyltransferase-independent manner. EZH2 augmented p53 GOF mutant-mediated cancer growth and metastasis by increasing protein levels of mutant p53. EZH2 overexpression was associated with worsened outcome selectively in patients with p53-mutated cancer. Depletion of EZH2 by antisense oligonucleotides inhibited p53 GOF mutant-mediated cancer growth. Our findings reveal a non-methyltransferase function of EZH2 that controls protein translation of p53 GOF mutants, inhibition of which causes synthetic lethality in cancer cells expressing p53 GOF mutants.

[Interaction between vaginal micro-environment alterations and HPV16 infection in cervical intraepithelial neoplasia]

Objective: To explore the effect of vaginal micro-environment alterations and HPV16 infection and their interaction in the progression of cervical intraepithelial neoplasia. Methods: The participants of this study came from the cervical lesions study cohort in Shanxi province, including 623 women with normal cervical (NC), 303 patients with pathogenically diagnosed low-grade cervical intraepithelial neoplasia (CINⅠ) and 93 patients with pathogenically diagnosed high-grade cervical intraepithelial neoplasia (CINⅡ/Ⅲ). The data of the demographic characteristics of the study subjects and factors related to cervical intraepithelial neoplasia were collected, and HPV16 infection were detected by using flow-through hybridization technology and H(2)O(2), β-glucuronidase, clotting enzyme, neuraminidase and leucocyte esterase in vaginal secretions were detected by using the combined detection kit of aerobic vaginitis and bacterial vaginosis. pH value and vaginal cleanliness were also detected at the same time. The database was established and analyzed by SPSS statistical software (version 22.0). Results: The HPV16 infection rate (trend χ(2)=55.45, P<0.001) and the abnormal rates of H(2)O(2) (trend χ(2)=26.19, P<0.001), pH (trend χ(2)=5.06, P=0.024), vaginal cleanliness (trend χ(2)=19.55, P<0.001), β-glucuronidase (trend χ(2)=17.52, P<0.001) and neuraminidase (trend χ(2)=14.90, P<0.001) increased gradually along with the severity of cervical intraepithelial neoplasia, but the abnormal rates of clotting enzyme and leucocyte esterase showed no same trend. The results of GMDR model analysis showed that there was interaction between HPV16 infection and abnormalities of H(2)O(2), β-glucuronidase, clotting enzyme and neuraminidase in CINⅠ group, and the interaction between HPV16 infection and the abnormalities of vaginal cleanliness, H(2)O(2), β-glucuronidase and neuraminidase in CIN Ⅱ/Ⅲ group. Conclusion: Our findings indicated that the vaginal micro-environment alterations and HPV16 infection could increase the risk of cervical intraepithelial neoplasia, and they might have an important synergistic effect in the progression of cervical intraepithelial neoplasia.

Abstract OT2-05-01: FAMILY: A randomized, multicenter, open-label, phase III trial of fulvestrant versus capecitabine as maintenance therapy after first-line combination chemotherapy in patients with hormone receptor-positive, human epidermal growth factor receptor-2 negative metastatic breast cancer

Background: Metastatic breast cancer (MBC) is incurable. Although first-line endocrine therapy is preferred to hormone receptor positive (HR+), human epidermal growth factor receptor-2 negative (HER2-) MBC, combination chemotherapy should be reserved as the initial treatment for patients with rapid clinical progression, life-threatening visceral metastases, and need for rapidly symptom control. Either prolonged chemotherapy or endocrine therapy may be used as maintenance after disease control. However, which maintenance strategy is superior in terms of delaying disease progression as well as maintaining quality of life (QOL) remains uncertain. This phase III trial aims to compare the efficacy and safety of fulvestrant or capecitabine as maintenance therapy after first-line combined chemotherapy in HR+/HER2- MBC.

Trial Design: FAMILY is a multicenter, randomized, open-label phase III trial for HR+ and HER2- MBC. Eligible participants are randomized (1:1) to receive capecitabine (2000mg/m2 twice daily x 14 days followed by 7 days off) or fulvestrant (500mg Days 0, 14, 28, then every 28 days) until disease progression, unacceptable toxicity, or patient refusal. Stratification factor for randomization is sensitivity to adjuvant hormonal therapy (disease-free interval ≤24 months vs. &gt;24 months).

Eligibility Criteria: Eligible patients must have HR+ (ER and/or PR&gt;1%, by IHC) and HER2- MBC; achieved a complete or partial response or stable disease (investigator assessed) after 4-8 cycles of first-line combination chemotherapy. Patients with central nervous system metastasis and/or prior use of endocrine therapy for advanced breast cancer are excluded.

Specific Aims: The primary endpoint is progression free survival (PFS). Secondary endpoints include overall survival, overall response rate, disease control rate, safety and QOL. A prospective translational research is also planned to assess the correlations between biomarkers and response.

Statistical Design: The planned sample size of 256 patients provides approximately 80% of power to detect a 6 months difference of PFS using a log-rank test with two-sided alpha of 0.05.

Target Accrual: Recruitment is ongoing. Up to 256 evaluable subjects will be enrolled within 24 months. (ChiCTR-IIR-17014036).

Citation Format: Yao H, Wu W, Ding L, Yu Y, Wang Y, Zeng Y, Zhao J, Li Q. FAMILY: A randomized, multicenter, open-label, phase III trial of fulvestrant versus capecitabine as maintenance therapy after first-line combination chemotherapy in patients with hormone receptor-positive, human epidermal growth factor receptor-2 negative metastatic breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-05-01.

PARP Inhibition Elicits STING-Dependent Antitumor Immunity in Brca1-Deficient Ovarian Cancer

PARP inhibitors have shown promising clinical activities for patients with BRCA mutations and are changing the landscape of ovarian cancer treatment. However, the therapeutic mechanisms of action for PARP inhibition in the interaction of tumors with the tumor microenvironment and the host immune system remain unclear. We find that PARP inhibition by olaparib triggers robust local and systemic antitumor immunity involving both adaptive and innate immune responses through a STING-dependent antitumor immune response in mice bearing Brca1-deficient ovarian tumors. This effect is further augmented when olaparib is combined with PD-1 blockade. Our findings thus provide a molecular mechanism underlying antitumor activity by PARP inhibition and lay a foundation to improve therapeutic outcome for cancer patients.

[Effect of hnRNP K and its interaction with HPV16 on cervical intraepithelial neoplasia]

Objective: To investigate the effect of heterogeneous nuclear ribonucleoprotein K (hnRNP K) and its interaction with human papillomavirus 16 (HPV16) on cervical intraepithelial neoplasia (CIN). Methods: The participants included 67 women with normal cervix (NC), 69 women with CINⅠ and 68 women with CINⅡ/Ⅲ in a community cohort of pathologically diagnosed women established in Jiexiu of Shanxi province, from June 2014 to June 2015. A structured questionnaire was used to collect the demographic data of the subjects and the related factors of cervical lesions. Cervical exfoliated cells and cervical tissues from biopsy or surgery were selected. The infection status of HPV16 was detected by flow-through hybridization. The protein expression levels of hnRNP K were evaluated by Western blot. SPSS 23.0 software was used to collate and analyze the data. To study the differences in demographic characteristics, related factors, hnRNP K protein and HPV16 infection among NC, CINⅠand CINⅡ/Ⅲgroups, χ(2) test, trend χ(2) test, and Kruskal-Wallis H test were conducted. Multiple comparisons of hnRNP K protein in three groups were completed by using the Bonferroni method. The OR and its 95%CI of hnRNP K, HPV16 and CIN were calculated by using the unconditional logistic regression models. Two-way interactions between hnRNP K protein and HPV16 infection on CIN were analyzed by using additive model and related indicators. Results: HPV16 infection rates were 10.4% in women with normal cervix, 14.5% in women with CINⅠ and 41.2% in women with CINⅡ/Ⅲ, respectively. The differences among three groups were significant (P<0.001). Moreover, the infection rates of HPV16 gradually increased with the increasing severity of CIN (trend χ(2)=18.512, P<0.001). The differences in protein expression of hnRNP K among three groups were significant (H=48.138, P<0.001) and the expressionincreased with the development of cervical lesionss (trend χ(2)=21.765, P<0.001). Results from the interaction analysis indicated that there were additive effects between high expression of hnRNP K protein and HPV16 in CINⅡ/Ⅲ group compared with normal group (API=0.639, 95%CI: 0.083-1.196). In contrast, no such additive effect was found in CINⅠ group. Conclusions: HPV16 infection and over-expression of hnRNP K protein were associated with the increased risk of cervical intraepithelial neoplasia. There might be interaction between hnRNP K protein overexpression and HPV16 infection existed on the progress of CINⅡ/Ⅲ.

[Etiological analysis on patients with vertigo or dizziness]

Objective: To explore the spectrum of causes for patients with vertigo or dizziness in the Department of Neurology, and provide a reference for diagnosis and treatment of patients with vertigo or dizziness. Methods: Clinical data of patients in the Department of Neurology, Baotou Central Hospital between January 2016 and September 2017 was retrospectively analyzed. The target group under study was diagnosed based on the uniform diagnostic criteria. Results: A total of 9 200 patients with a chief complaint of vertigo or dizziness were included. The ratio of male to female was 1∶1.8, with an age range of 19 to 85 years. The different etiology was as follows: benign paroxysmal positional vertigo (BPPV) (3 148 cases, 34.22%), persistent postural-perceptual dizziness (PPPD) (2 006 cases, 21.80%), vertigo caused by cerebrovascular diseases (1 463 cases, 15.90%), vestibular neuritis (741 cases, 8.05%), vestibular migraine (536 cases, 5.83%), vestibular paroxysmia (336 cases, 3.65%), Ménière disease (187 cases, 2.03%), drug-induced vertigo (96 cases, 1.04%), neurological degenerative diseases (74 cases, 0.80%), sudden sensorineural hearing loss (51 cases, 0.55%), multiple sclerosis and neuromyelitis optica (21 cases, 0.23%), other reasons (22 cases, 0.24%), unknown reasons (519 cases, 5.64%). Conclusions: Dizziness is resulted from various causes, and BPPV is the most common reason. Vertigo caused by cerebrovascular diseases appears to gradually increase along with age. PPPD is very common in clinical practice, so clinicians needs to be highly aware of BPPV and PPPD. Although those dizziness diseases have a low incidence, they should not be ignored. There are still certain proportion of vertigo patients whose diagnosis are undetermined.

Wilms' tumor 1-associating protein plays an aggressive role in diffuse large B-cell lymphoma and forms a complex with BCL6 via Hsp90

Background

Wilms’ tumor 1-associating protein (WTAP) is a nuclear protein, which is ubiquitously expressed in many tissues. Furthermore, in various types of malignancies WTAP is overexpressed and plays a role as an oncogene. The function of WTAP in diffuse large B-cell lymphoma (DLBCL), however, remains unclear.

Methods

Immunohistochemistry was applied to evaluate the levels of WTAP expression in DLBCL tissues and normal lymphoid tissues. Overexpression and knock-down of WTAP in DLBCL cell lines, verified on mRNA and protein level served to analyze cell proliferation and apoptosis in DLBCL cell lines by flow cytometry. Finally, co-immunoprecipitation (Co-IP), IP, and GST-pull down assessed the interaction of WTAP with Heat shock protein 90 (Hsp90) and B-cell lymphoma 6 (BCL6) as well as determined the extend of its ubiquitinylation.

Results

WTAP protein levels were consistently upregulated in DLBCL tissues. WTAP promoted DLBCL cell proliferation and improved the ability to confront apoptosis, while knockdown of WTAP in DLBCL cell lines allowed a significant higher apoptosis rate after treatment with Etoposide, an anti-tumor drug. The stable expression of WTAP was depended on Hsp90. In line, we demonstrated that WTAP could form a complex with BCL6 via Hsp90 in vivo and in vitro.

Conclusion

WTAP is highly expressed in DLBCL, promoting growth and anti-apoptosis in DLBCL cell lines. WTAP is a client protein of Hsp90 and can appear in a complex with BCL6 and Hsp90 in DLBCL. Down-regulation of WTAP could improve the chemotherapeutic treatments in DLBCL.

Electronic supplementary material

The online version of this article (10.1186/s12964-018-0258-6) contains supplementary material, which is available to authorized users.