Pretreatment MRI-Derived Radiomics May Evaluate the Response of Different Induction Chemotherapy Regimens in Locally advanced Nasopharyngeal Carcinoma

RATIONALE AND OBJECTIVES

To evaluate and compare the performance of radiomics in predicting induction chemotherapy response treated with two different regimens in patients with advanced nasopharyngeal carcinoma.

MATERIALS AND METHODS

A total of 265 patients with pathologically confirmed locally advanced nasopharyngeal carcinoma (stage II-IV), including 115 treated with gemcitabine plus cisplatin (GP group) and 150 treated with docetaxel plus cisplatin (TP group) were retrospectively enrolled. Radiomics features were extracted from the volume of interest delineated in multi-MR sequences on a 3T scanner. After random stratified grouping (training and validation cohorts) and logistic regression based on selected features, the association between the radiomics signature and the early response to induction chemotherapy were established for GP and TP regiments, respectively.

RESULTS

Clinical factors showed no significant difference between the response and non-response groups for the GP and TP regiments (all p > 0.05). The accuracy of the radiomics signature consisting of selected features from the joint T1, T2, and T1C in the GP group (0.852 in the training cohort vs. 0.853 in the validation cohort) was significantly higher than that in the TP group (0.774 vs 0.727). The overall performance of the GP model was steady, with efficiency to distinguish responders from nonresponders with an AUC reaching 0.907 (95% confidence interval [CI] [0.843-0.970]) in the training cohort and 0.886 (95% CI [0.772-0.998]) in the validation cohort, while leveling at 0.800 (95% CI [0.712-0.888]) in the training cohort and 0.863 (95% CI [0.758-0.967]) in the validation cohort in the TP group.

CONCLUSION

Pretreatment MR radiomics signature can better predict the early response to IC in the GP regimen than the TP regimen, which may be helpful to guide IC management.

CRISPR/Cas9-mediated LMP1 knockout inhibits Epstein-Barr virus infection and nasopharyngeal carcinoma cell growth

Background

A strong association between Epstein-Barr virus (EBV) infection and nasopharyngeal carcinoma (NPC) has been widely recognized in recent decades. The aim of the present study was to investigate latent membrane protein 1 (LMP1) regulation of nasopharyngeal carcinoma (NPC) CNE-2 cell growth and then examine the effects of LMP1-knockout with CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9on Epstein-Barr virus (EBV) infection and CNE-2 cell growth.

Methods

Human NPC CNE-2 cells were infected with the recombinant LMP1- and LMP2A-carrying lentivirus, and then examined for cell growth with the colony forming assay as well as for the activation of transcription of eukaryotic translation initiation factor 4E (eIF4E) with reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) and western blot. CRISPR/Cas9-mediated knockout of LMP1 or LMP2A was performed with a single-guide RNA (sgRNA) targeting sequences within LMP1 or LMP2A. The knockout effect and the EBV proliferation were examined with RT-qPCR, western blot and cell growth assay.

Results

LMP1 overexpression promoted CNE-2 cell growth, compared to LMP2A overexpression. Loss-of-function experiments confirmed that eukaryotic translation initiation factor 4E (eIF4E) upregulation mediated this effect. LMP1 knockout significantly inhibited EBV proliferation in CNE-2 cells and markedly inhibited LMP1-mediated promotion of cell growth. The knockout of either LMP1 or LMP2A blocked the eIF4E activation, which is induced either by the EBV infection or by the overexpression of LMP1 or LMP2A.

Conclusion

We confirmed the LMP1-mediated promotion of NPC cell growth. Such promotion can be effectively blocked by CRISPR/Cas9-mediated LMP1 knockout. Precise LMP1 knockout might be a promising method for targeted inhibition of EBV infection and NPC cell growth.

Downregulation of FoxM1 sensitizes nasopharyngeal carcinoma cells to cisplatin via inhibition of MRN-ATM-mediated DNA repair

Chemoresistance is the primary obstacle in the treatment of locally advanced and metastatic nasopharyngeal carcinoma (NPC). Recent evidence suggests that the transcription factor forkhead box M1 (FoxM1) is involved in chemoresistance. Our group previously confirmed that FoxM1 is overexpressed in NPC. In this study, we investigated the role of FoxM1 in cisplatin resistance of the cell lines 5–8F and HONE-1 and explored its possible mechanism. Our results showed that FoxM1 and NBS1 were both overexpressed in NPC tissues based on data from the GSE cohort (GSE12452). Then, we measured FoxM1 levels in NPC cells and found FoxM1 was overexpressed in NPC cell lines and could be stimulated by cisplatin. MTT and clonogenic assays, flow cytometry, γH2AX immunofluorescence, qRT-PCR, and western blotting revealed that downregulation of FoxM1 sensitized NPC cells to cisplatin and reduced the repair of cisplatin-induced DNA double-strand breaks via inhibition of the MRN (MRE11-RAD50-NBS1)-ATM axis, which might be related to the ability of FoxM1 to regulate NBS1. Subsequently, we demonstrated that enhanced sensitivity of FoxM1 knockdown cells could be reduced by overexpression of NBS1. Taken together, our data demonstrate that downregulation of FoxM1 could improve the sensitivity of NPC cells to cisplatin through inhibition of MRN-ATM-mediated DNA repair, which could be related to FoxM1-dependent regulation of NBS1.

Downregulation of FoxM1 sensitizes nasopharyngeal carcinoma cells to cisplatin via inhibition of MRN-ATM-mediated DNA repair

Chemoresistance is the primary obstacle in the treatment of locally advanced and metastatic nasopharyngeal carcinoma (NPC). Recent evidence suggests that the transcription factor forkhead box M1 (FoxM1) is involved in chemoresistance. Our group previously confirmed that FoxM1 is overexpressed in NPC. In this study, we investigated the role of FoxM1 in cisplatin resistance of the cell lines 5-8F and HONE-1 and explored its possible mechanism. Our results showed that FoxM1 and NBS1 were both overexpressed in NPC tissues based on data from the GSE cohort (GSE12452). Then, we measured FoxM1 levels in NPC cells and found FoxM1 was overexpressed in NPC cell lines and could be stimulated by cisplatin. MTT and clonogenic assays, flow cytometry, γH2AX immunofluorescence, qRT-PCR, and western blotting revealed that downregulation of FoxM1 sensitized NPC cells to cisplatin and reduced the repair of cisplatin-induced DNA double-strand breaks via inhibition of the MRN (MRE11-RAD50-NBS1)-ATM axis, which might be related to the ability of FoxM1 to regulate NBS1. Subsequently, we demonstrated that enhanced sensitivity of FoxM1 knockdown cells could be reduced by overexpression of NBS1. Taken together, our data demonstrate that downregulation of FoxM1 could improve the sensitivity of NPC cells to cisplatin through inhibition of MRN-ATM-mediated DNA repair, which could be related to FoxM1-dependent regulation of NBS1. [BMB Reports 2019; 52(3): 208-213].

Inhibition of autophagy by chloroquine makes chemotherapy in nasopharyngeal carcinoma more efficient

OBJECTIVES

A combination of platinum-based chemotherapy and radiotherapy is the standard treatment for nasopharyngeal carcinoma (NPC). However, the efficacy of chemotherapy has reached a plateau. Many autophagy studies suggest that autophagy can either promote or suppress to cancer progression. Thus, a role of autophagy in the acquisition of chemoradioresistance has recently been a notable event. Therefore, we examined the relationship between autophagy and chemotherapy in NPC.

METHODS

The expression of Beclin 1 and microtubule-associated protein light chain 3 (LC3), a marker of autophagy, was determined by immunohistochemistry in the biopsy samples of patients with NPC before and after the first course of chemotherapy. Additionally, to investigate in the effect of autophagy suppression in chemotherapy, NPC cell line C666-1 cells were treated with cisplatin and/or chloroquine, an inhibitor of autophagy.

RESULTS

The expression of Beclin 1 increased after chemotherapy in all patients. In NPC cell line C666-1, compared to cisplatin alone, combination therapy (cisplatin and chloroquine) reduced cell viability, and promoted cell apoptosis.

CONCLUSIONS

These results suggest that autophagy, represented by Beclin 1, is upregulated after chemotherapy in both in vitro and in vivo NPC studies. Inhibition of autophagy could therefore be new strategy for NPC treatment.

Coronarin D induces reactive oxygen species-mediated cell death in human nasopharyngeal cancer cells through inhibition of p38 MAPK and activation of JNK

Background and Purpose

Nasopharyngeal carcinoma (NPC) belongs to squamous cell carcinoma that occurs in the epithelial lining of the nasopharynx. Because of the anatomical position close to the cervical lymph node, some patients have a distant metastasis at the time of diagnosis that leads to treatment failure. Although early stages have a high curability and excellent prognosis, advanced NPC urgently requires new drugs developed to reinforce the effectiveness of therapy without noticeable side effects.

Experimental approach

Coronarin D (CD), a natural product extracted from the rhizomes of Hedychium coronarium, has been reported to possess anticancer potential. The aim of the present study was to determine the anticancer activity of CD and further elucidate the underlying molecular mechanisms.

Key Results

In this study, we first demonstrated that CD potently suppressed cell viability in various NPC cell lines. Treatment of cells with CD induced G2/M arrest, apoptosis, and autophagy. Further studies showed that CD increased the production of reactive oxygen species and subsequently activated both autophagy and apoptosis. Moreover, we found that CD-induced activation of p38 and JNK constituted major mechanisms involved in the apoptosis and autophagy triggered by CD. In particular, inhibition of autophagy could strengthen the cytotoxicity of CD, implying that autophagy seems to play a valuable survival and protective role in cancer cells.

Conclusions & Implications

These findings provide a promise for the use of CD in combination with autophagy inhibitors for treatment of human NPC cell lines.

Prognostic value of 18F-fluorodeoxyglucose PET parameters and inflammation in patients with nasopharyngeal carcinoma

The aim of the present study was to investigate the association between positron emission tomography (PET) parameters and peripheral inflammatory markers, and assess their prognostic value in nasopharyngeal carcinoma (NPC). A total of 121 patients with non-disseminated NPC were recruited. Pretreatment maximum standardized uptake values (SUVmax) of PET and peripheral inflammatory factors (leukocyte, neutrophil and monocyte counts) were recorded. Kaplan-Meier and multivariate analyses were used to identify predictors for progression-free survival (PFS), overall survival (OS), distant metastasis-free survival (DMFS) and locoregional recurrence-free survival (LRFS). The results of the present study revealed that SUVmax at the primary tumor was positively correlated with leukocytes (P=0.025), neutrophils (P=0.009) and monocytes (P=0.043). SUVmax at regional lymph nodes (SUVmax-N) was significantly associated with monocytes (P=0.024). Kaplan-Meier analysis demonstrated that SUVmax-N (>10.15) significantly predicted PFS (P=0.004) and DMFS (P=0.003). In addition, neutrophils (>5.18) were significantly associated with PFS (P=0.001), DMFS (P=0.013) and LRFS (P<0.001). Multivariate analysis revealed that SUVmax-N and neutrophils retained independent prognostic significance for PFS (SUVmax-N, P=0.026; and neutrophils, P=0.033) and DMFS (SUVmax-N, P=0.026; and neutrophils, P=0.032). Furthermore, patients with SUVmax-N ≤10.15 and neutrophils ≤5.18 had significantly improved prognosis in PFS (96.4 vs. 58.5%, P<0.001), OS (95.7 vs. 81.1%, P=0.044), DMFS (96.4 vs. 67.0%, P<0.001) and LRFS (100 vs. 90.2%, P=0.036) compared with those with SUVmax-N >10.15 or neutrophils >5.18. In conclusion, SUVmax may be significantly associated with cancer-associated inflammation. SUVmax-N and neutrophils were independent prognostic indicators for PFS and DMFS. Combined assessment of SUVmax-N and neutrophils may lead to refinement of risk stratification in NPC.

Potential Interest in Circulating miR-BART17-5p As a Post-Treatment Biomarker for Prediction of Recurrence in Epstein-Barr Virus-Related Nasopharyngeal Carcinoma

Objectives

Epstein-Barr virus (EBV)-related micoRNAs (miRNAs), BamHI-A rightward transcripts (BART)-miRNAs, are released in a stable form from viable cells, which are abundant in patients with EBV-positive nasopharyngeal carcinoma (NPC). We estimated copy numbers of circulating miR-BART2-5p, miR-BART17-5p, and miR-BART18-5p as well as BamHI-W DNA as biomarkers.

Materials and Methods

Serums from 31 EBV-positive (confirmed by in situ hybridization for EBV-encoded small RNAs) NPC patients and 40 non-NPC controls were analyzed. Among the 31 NPC patients, serums at the initial diagnosis and three months after treatment were obtained from 20 patients, and serums only at three months after treatment were obtained from 11 patients.

Results

The sensitivity/specificity of circulating BamHI-W DNA, miR-BART2-5p, miR-BART17-5p, and miR-BART18-5p for the diagnosis of NPC before treatment were 100 / 100, 85 / 85, 60 / 95, and 25 / 100%, respectively. For BamHI-W DNA, NPC patients with stage IV disease had significantly higher copy numbers than those with I-III. Copy numbers decreased significantly post-treatment. In contrast, copy numbers of the three BART-miRNAs showed no significant correlation with the clinical stage at diagnosis or any significant post-treatment change. After treatment, BamHI-W DNA and miR-BART17-5p were detected in 5 and 6 cases out of 11 patients with recurrent or residual tumors, respectively. However, BamHI-W DNA and miR-BART17-5p were absent in all 20 patients without relapse or residual tumors.

Conclusion

The copy number of circulating BamHI-W DNA is a more useful biomarker for the initial diagnosis of NPC than the three BART-miRNAs examined. Post-treatment detection of miR-BART17-5p is a potential biomarker of a poor prognosis.

Neoadjuvant chemotherapy plus intensity-modulated radiotherapy versus concurrent chemoradiotherapy plus adjuvant chemotherapy for the treatment of locoregionally advanced nasopharyngeal carcinoma: a retrospective controlled study

Background

In the era of intensity-modulated radiotherapy (IMRT), the role of neoadjuvant chemotherapy (NAC) for locoregionally advanced nasopharyngeal carcinoma (NPC) is under-evaluated. The aim of this study was to compare the efficacy of NAC plus IMRT and concurrent chemoradiotherapy (CCRT) plus adjuvant chemotherapy (AC) on locoregionally advanced NPC.

Methods

Between January 2004 and December 2008, 240 cases of locoregionally advanced NPC confirmed by pathologic assessment in Sun Yat-sen University Cancer Center were reviewed. Of the 240 patients, 117 received NAC followed by IMRT, and 123 were treated with CCRT plus AC. The NAC + IMRT group received a regimen that included cisplatin and 5-fluorouracil (5-FU). The CCRT + AC group received cisplatin concurrently with radiotherapy, and subsequently received adjuvant cisplatin and 5-FU. The survival rates were assessed by Kaplan–Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model.

Results

The 5-year overall survival (OS), locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) were 78.0, 87.9, 79.0, and 69.8%, respectively, for the NAC + IMRT group and 78.7, 84.8, 76.2, and 65.6%, respectively, for the CCRT + AC group. There were no significant differences in survival between the two groups. In multivariate analysis, age (<50 years vs. ≥50 years) and overall stage (III vs. IV) were found to be independent predictors for OS and DFS; furthermore, the overall stage was a significant prognostic factor for DMFS. Compared with the CCRT + AC protocol, the NAC + IMRT protocol significantly reduced the occurrence rates of grade 3–4 nausea–vomiting (6.5 vs. 1.5%, P = 0.023) and leukopenia (9.7 vs. 0.8%, P = 0.006).

Conclusions

The treatment outcomes of the NAC + IMRT and CCRT + AC groups were similar. Distant metastasis remained the predominant mode of treatment failure.