Prognostic Value of Lymph Node-to-Primary Tumor Ratio of PET Standardized Uptake Value for Nasopharyngeal Carcinoma: A Recursive Partitioning Risk Stratification Analysis

PURPOSE/OBJECTIVE(S)

To evaluate the prognostic value of the lymph node-to-primary tumor ratio (NTR) of positron emission tomography (PET) standardized uptake value (SUV) for nasopharyngeal carcinoma (NPC) patients treated with induction chemotherapy (IC).

MATERIALS/METHODS

Four hundred and sixty-seven locoregionally advanced NPC patients with pretreatment 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) scans between September 2017 and November 2020 were retrospectively reviewed. All patients underwent IC plus intensity-modulated radiotherapy (IMRT). The receiver operating characteristic (ROC) analysis was used to determine the optimal cut-off value of SUV NTR. Kaplan-Meier method was used to evaluate survival rates. The recursive partitioning analysis (RPA) was performed to construct a risk stratification model.

RESULTS

The optimal cut-off value of SUV NTR was 0.74. Multivariate analyses showed that SUV NTR and overall stage were independent predictors for distant metastasis-free survival (DMFS) and regional recurrent-free survival (RRFS). Therefore, an RPA model based on the endpoint of DMFS was generated and categorized the patients into three distinct risk groups: RPA I (low-risk: SUV NTR<7.4 and stage III), RPA II (medium-risk: SUV NTR<7.4 and stage IVa, or SUV NTR≥7.4 and stage III), and RPA III (high-risk: SUV NTR≥7.4 and stage IVa), with a 3-year DMFS of 98.9%, 93.4%, and 84.2%, respectively. ROC analysis showed that the RPA model had superior predictive efficacy than the SUV NTR or overall stage alone.

CONCLUSION

SUV NTR was an independent prognosticator for distant metastasis and regional recurrence in locoregionally advanced NPC. The RPA risk stratification model base on SUV NTR provides improved DMFS and RRFS prediction over the 8th edition of the TNM staging system.

Radiotherapy Alone vs. Concurrent or Adjuvant Chemoradiotherapy for Nasopharyngeal Carcinoma Patients with Negative Epstein-Barr Virus DNA Post-Induction Chemotherapy

PURPOSE/OBJECTIVE(S)

Induction chemotherapy (IC) plus concurrent chemoradiotherapy has been recommended as the standard treatment for locoregionally advanced nasopharyngeal carcinoma (LA-NPC). However, concurrent chemotherapy was associated with increased toxicities, poor tolerance, and low completion rates. The aim of this study was to compare the efficacy and toxicity of IC+ radiotherapy (RT) and IC+ concurrent or adjuvant chemoradiotherapy (IC+CCRT/AC) in patients with negative post-IC EBV DNA.

MATERIALS/METHODS

A total of 547 NPC patients with negative plasma EBV DNA post-IC were included. Patients were classified into the IC+RT group and the IC+ concurrent or adjuvant chemoradiotherapy (IC+CCRT/AC) group. Locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS), overall survival (OS), and progression-free survival (PFS) were estimated and compared using the Kaplan-Meier method. Propensity-score matching (PSM) was performed to balance the variables.

RESULTS

The median follow-up time was 37 months. The 3-year LRFS, DMFS, OS, and PFS rates for the whole group were 92.2%, 92.4%, 96.4%, and 84.4%, respectively. There was no significant difference in LRFS, DMFS, OS, and PFS between the IC+RT and the IC+CCRT/AC group both before PSM (3-year rates of 91.1% vs. 92.6%, p = 0.94; 95.6% vs. 91.5%, p = 0.08; 95.2% vs. 96.8%, p = 0.80; 85.9% vs. 84.0%, p = 0.38) and after PSM (90.7% vs. 92.7%, p = 0.77; 96.8% vs. 93.7%, p = 0.29; 94.5% vs. 93.9%, p = 0.57; 84.7% vs. 85.6%, p = 0.96). Multivariate analysis demonstrated that treatment schedule was not an independent predictor for survival rates. Patients in the IC+RT group had fewer treatment-related acute toxicities and better tolerance.

CONCLUSION

IC+RT displayed similar survival outcomes as IC+CCRT/AC for NPC patients with negative post-IC EBV DNA. Our current data seems not to support the routine use of concurrent or adjuvant chemotherapy after IC for unselected patients.

lncRNA MIR210HG promotes the progression of endometrial cancer by sponging miR-337-3p/137 via the HMGA2-TGF-β/Wnt pathway

Epithelial-mesenchymal transition (EMT) promotes tumorigenesis and metastasis and increases tumor tolerance to treatment intervention. Abnormal activation of transforming growth factor β (TGF-β) and Wnt pathway induces EMT. Long non-coding RNAs (lncRNAs) significantly influence EMT regulation. Herein, we show that MIR210HG is overexpressed in endometrial cancer tissues, which is associated with poor prognosis. MIR210HG silencing significantly inhibited proliferation, migration, invasion, and EMT phenotype formation in vitro as well as tumorigenesis in vivo. Mechanistically, bioinformatics analyses, RNA binding protein immunoprecipitation (RIP) assays, and luciferase assays showed that MIR210HG acts as a molecular sponge of miR-337-3p and miR-137 to regulate the expression of HMGA2. Additionally, MIR210HG overexpression significantly enriched the Wnt/β-catenin and TGF-β/Smad3 signaling pathway genes, while MIR210HG or HMGA2 knockdown suppressed the Wnt/β-catenin and TGF-β/Smad3 signaling pathway. Our findings on the MIR210HG-miR-337-3p/137-HMGA2 axis illustrate its potential as a target for endometrial cancer therapeutic development.

miR-302a-5p/367-3p-HMGA2 axis regulates malignant processes during endometrial cancer development

BACKGROUND

Metastasis is one of the main reasons for treatment failure in endometrial cancer. Notably, high mobility group AT-hook 2 (HMGA2) has been recognized as a driving factor of tumour metastasis. microRNAs (miRNAs) are powerful posttranscriptional regulators of HMGA2.

METHODS

The binding sites of miR-302a-5p and miR-367-3p on HMGA2 mRNA were identified using bioinformatics prediction software and were validated via luciferase assay. The expression levels of miR-302a-5p and miR-367-3p were detected using quantitative real-time PCR and in situ hybridization. Western blotting and immunohistochemistry were used to detect the levels of HMGA2 and epithelial-mesenchymal transition pathway-related proteins. Co-immunoprecipitation was used to detect protein interactions. The roles of miR-302a-5p and miR-367-3p in the regulation of HMGA2 during the progression of endometrial cancer were investigated using both in vitro and in vivo assays.

RESULTS

In the present study, high HMGA2 expression was correlated with poor clinical outcomes in endometrial cancer. The binding sites of miRNAs on HMGA2 mRNA were identified using bioinformatics prediction software and were validated via luciferase assay. In the endometrial cancer cell lines Ishikawa and HEC-1A, the overexpression of miR-302a-5p/367-3p significantly inhibited the expression of HMGA2 mRNA. In endometrial cancer tissues, we showed that miR-302a-5p and miR-367-3p were significantly downregulated and thus inversely correlated with HMGA2. The miR-302a-5p and miR-367-3p expression levels were closely correlated with FIGO stage and lymph node metastasis. High expression of miR-302a-5p/367-3p was correlated with high survival rates in endometrial cancer. In addition, miR-302a-5p/367-3p suppressed the malignant behaviour of endometrial carcinoma cells via the inhibition of HMGA2 expression.

CONCLUSION

Our findings indicate that miR-302a-5p/367-3p-mediated expression of HMGA2 regulates the malignant behaviour of endometrial carcinoma cells, which suggests that the miR-302a-5p/367-3p-HMGA2 axis may be a predictive biomarker of endometrial cancer metastasis and patient survival and a potential therapeutic target in metastatic endometrial cancer.

Preliminary identification of endometrial cancer stem cells in vitro and in vivo

Stem cells play a critical role in endometrial cancer progression. However, the current methodologies used to isolate endometrial cancer stem cells (ECSCs) remain unsatisfactory. The ECSCs were isolated by serumfree suspension cultivation. The stem cells-related genes CD44, CD133, Oct4, Sox2 and Nanog were analyzed, and the biological behaviour of ECSCs was evaluated in vitro and vivo. The results suggest that (i) serumfree suspension cultivation is non-toxic and a convenient way for isolating the ECSCs, and is not limited to specific surface markers; (ii) Ishikawa cells can be used as an effective source of ECSCs, and the obtained ECSCs expressing the pluripotent stem cells markers CD44, CD133, Oct4, Sox2, and Nanog; (iii) ECSCs originated from Ishikawa cells showed an increased ability to invasion and metastasis in vitro, and exhibited a high proliferative capacity and pluripotency in vivo and vitro. These findings indicate that serumfree suspension cultivation is an effective method for isolating ECSCs from Ishikawa cells, and the obtained ECSCs are tumorigenic and display stem cell-like properties.

HPV16 integration probably contributes to cervical oncogenesis through interrupting tumor suppressor genes and inducing chromosome instability

Background

The integration of human papilloma virus (HPV) into host genome is one of the critical steps that lead to the progression of precancerous lesion into cancer. However, the mechanisms and consequences of such integration events are poorly understood. This study aims to explore those questions by studying high risk HPV16 integration in women with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (SCC).

Methods

Specifically, HPV integration status of 13 HPV16-infected patients were investigated by ligation-mediated PCR (DIPS-PCR) followed by DNA sequencing.

Results

In total, 8 HPV16 integration sites were identified inside or around genes associated with cancer development. In particular, the well-studied tumor suppressor genes SCAI was found to be integrated by HPV16, which would likely disrupt its expression and therefore facilitate the migration of tumor. On top of that, we observed several cases of chromosome translocation events coincide with HPV integration, which suggests the existence of chromosome instability. Additionally, short overlapping sequences were observed between viral derived and host derived fragments in viral-cellular junctions, indicating that integration was mediated by micro homology-mediated DNA repair pathway.

Conclusions

Overall, our study suggests a model in which HPV16 might contribute to oncogenesis not only by disrupting tumor suppressor genes, but also by inducing chromosome instability.

Electronic supplementary material

The online version of this article (doi:10.1186/s13046-016-0454-4) contains supplementary material, which is available to authorized users.

[Proteasome inhibitors sensitize ovarian cancer cells to paclitaxel induced apoptosis]

OBJECTIVE

To explore the sensitivity of ovarian cancer cell line SKOV3 to paclitaxel, proteasome inhibitors, bortezomib, and their combination.

METHODS

The methyl thiazolyl tetrazolium (MTT) assay was applied to examine the cell viability after treatment. The annexin V-propidium iodide apoptosis detection kit was used to determine the apoptosis rate of different groups. Western blot assay was used to evaluate the expression levels of phosphorylated protein kinase B (AKT) and glycogen synthase kinase-3 beta (GSK-3beta).

RESULTS

In MTT assay, the cell viability ratios of the combination group at serial time points from 12, 24, 36, 48 and 72 hours were (65.2 +/- 5.8)%, (58.3 +/- 14.4)%, (35.3 +/- 5.0)%, (19.2 +/- 1.5)%, and (11.4 +/- 2.5)%, which were significantly lower than those of the paclitaxel group (P < 0.05). After drug treatments, apoptosis rates of paclitaxel group, bortezomib group and the combination group were (14.7 +/- 0.5)%, (15.1 +/- 0.8)% and (20.5 +/- 0.7)% respectively. The rate of the combination group was significantly higher than that of non-treated group and paclitaxel group (P < 0.05). Western blot assay showed the changes in expression levels of phosphorylated AKT and GSK-3beta, which were decreased significantly after paclitaxel and bortezomib combination treatment [(3.2 +/- 0.8)%, (19.3 +/- 0.4)%; P < 0.05].

CONCLUSIONS

The lethal effect of paclitaxel on tumor cells could be increased significantly by its combination with proteasome inhibitors, bortezomib. The AKT/GSK-3beta signaling pathway plays an important role in the molecular mechanism of the combination treatment.