Development and validation of a transcriptomics-based gene signature to predict distant metastasis and guide induction chemotherapy in locoregionally advanced nasopharyngeal carcinoma.

AIM: Metastasis is the primary cause of treatment failure in nasopharyngeal carcinoma (NPC); however, the current tumour-node-metastasis staging system has limitations in predicting distant metastasis and guiding induction chemotherapy (IC) application. Here, we established a transcriptomics-based gene signature to assess the risk of distant metastasis and guide IC in locoregionally advanced NPC. METHODS: Transcriptome sequencing was performed on NPC biopsy samples from 12 pairs of patients with different metastasis risks. Bioinformatics and qPCR were used to identify differentially expressed genes (DEGs), while univariate and multivariate analyses were used to select prognostic indicators for the gene signature. A signature-based nomogram was established in a training cohort (n = 191) and validated in an external cohort (n = 263). RESULTS: Eleven DEGs were identified between metastatic and non-metastatic NPC. Four of these (AK4, CPAMD8, DDAH1 and CRTR1) were used to create a gene signature that effectively categorised patients into low- and high-risk metastasis groups (training: 91.1 versus 70.4%, p < 0.0001, C-index = 0.752; validation: 88.4 versus 73.9%, p = 0.00057, C-index = 0.741). IC with concurrent chemoradiotherapy (CCRT) improved distant metastasis-free survival in low-risk patients (94.4 versus 85.0%, p = 0.043), whereas patients in the high-risk group did not benefit from IC (72.6 versus 74.9%, p = 0.946). CONCLUSIONS: Our transcriptomics-based gene signature was able to reliably predict metastasis in locoregionally advanced NPC and could be used to identify candidates that could benefit from IC + CCRT.

Development and validation of the immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma.

BACKGROUND: The tumor immune microenvironment has clinicopathological significance in predicting prognosis and therapeutic efficacy. We aimed to develop an immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma (NPC). METHODS: Using multiplexed quantitative fluorescence, we detected 17 immune biomarkers in a primary screening cohort of 54 NPC tissues presenting with/without distant metastasis following radical therapy. The LASSO (least absolute shrinkage and selection operator) logistic regression model used statistically significant survival markers in the training cohort (n=194) to build an immune signature. The prognostic and predictive accuracy of it was validated in an external independent group of 304 patients. RESULTS: Eight statistically significant markers were identified in the screening cohort. The immune signature consisting of four immune markers (PD-L1+ CD163+, CXCR5, CD117) in intratumor was adopted to classify patients into high and low risk in the training cohort and it showed a high level of reproducibility between different batches of samples (r=0.988 for intratumor; p<0.0001). High-risk patients had shorter distant metastasis-free survival (HR 5.608, 95% CI 2.619 to 12.006; p<0.0001) and progression-free survival (HR 2.798, 95% CI 1.498 to 5.266; p=0·001). The C-indexes which reflected the predictive capacity in training and validation cohort were 0.703 and 0.636, respectively. Low-risk patients benefited from induction chemotherapy plus concurrent chemoradiotherapy (IC+CCRT) (HR 0.355, 95% CI 0.147 to 0.857; p=0·021), while high-risk patients did not (HR 1.329, 95% CI 0.543 to 3.253; p=0·533). To predict the individual risk of distant metastasis, nomograms with the integration of both immune signature and clinicopathological risk factors were developed. CONCLUSIONS: The immune signature provided a reliable estimate of distant metastasis risk in patients with NPC and might be applied to identify the cohort which benefit from IC+CCRT.

Altered expression of E-cadherin by hepatocyte growth factor and effect on the prognosis of nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: Hepatocyte growth factor (HGF)-related E-cadherin expression and prognosis of patients with nasopharyngeal carcinoma (NPC) are not fully understood. This study investigated HGF-induced altered expression of E-cadherin and the relationship between prognosis and modulation of E-cadherin by HGF in NPC. METHODS: 135 cases of NPC were collected, and expression of HGF, c-Met, and E-cadherin in tissue microarray was evaluated by immunohistochemical staining. Correlation between immunostainings and clinicopathological parameters, as well as the follow-up data of patients, was analyzed statistically. The association and alteration of E-cadherin by HGF treatment in NPC cell lines were evaluated by immunocytochemical staining, Western blot, and invasion assay. RESULTS: Both high HGF expression in tumor cells (62.9%, 85/135 cases) and nonmembranous E-cadherin expression (61.5%, 83/135 cases) were significantly associated with advanced clinical stage, lymph node metastasis, and worse prognosis of NPC patients. However, only abnormal E-cadherin expression (P = 0.001) and lymph node metastasis (P = 0.004) emerged as strong independent prognostic factors for overall survival of NPC patients. In vitro, exogenous HGF decreased and internalized E-cadherin expression from cell membrane to cytoplasm, with obvious cellular morphological change. HGF-treated NPC cells exhibited significantly enhanced invasive ability in Matrigel matrix-coated Transwell chamber assay. CONCLUSION: HGF may contribute to cell invasion in NPC by modulating E-cadherin-mediated cell-cell adhesion through downregulation and internalization of E-cadherin. Altered expression of E-cadherin by HGF is a valuable predictor for prognostic evaluation of NPC patients.

Co-elevated expression of hepatocyte growth factor and Interleukin-8 contributes to poor prognosis of patients with primary nasopharyngeal carcinoma.

Hepatocyte growth factor (HGF) related tumor angiogenesis and prognosis of patients with nasopharyngeal carcinoma (NPC) has not been identified. The expressions of HGF and IL-8, as well as microvessels density were evaluated in 127 NPC biopsies by immunohistochemical staining. The correlation between these parameters and patient's clinicopathological features was analyzed statistically. In vitro, IL-8 concentration was evaluated in exogenous HGF-treated NPC cell lines by ELISA assay. The presence of EBV was also detected in NPC cells by PCR for Bam HI-W fragment. Both 54.3% (69/127) cases of HGF high-expression in tumor cells and 80.3% (102/127) of HGF high-expression in stromal cells were significantly associated with increased microvessels density, advanced clinical stage, lymph node metastasis and high-expression of IL-8. Angiogenesis exhibited in relation to overall survival of NPC patients (P=0.001), and the patients with HGF and IL-8 dual high-expression tumors had a significantly worse prognosis than those with single protein high-expression and dual low expression tumors (P=0.011 and P=0.026, respectively). Exogenous HGF was observed to promote induction of IL-8 in NPC cells without EBV infection. Co-operating with IL-8, HGF might contribute to a poor prognosis of NPC by inducing angiogenesis through both autocrine and paracrine EBV-independent pathways.

Expression of protease-activated receptor-2 (PAR-2) in patients with nasopharyngeal carcinoma: correlation with clinicopathological features and prognosis.

We aimed at determining whether the expression of protease-activated receptor 2 (PAR-2) is involved in the progression of nasopharyngeal carcinoma (NPC) and correlated with latent membrane protein 1 (LMP-1), matrix metalloproteinases-9 (MMP9), and angiogenesis of tumor. PAR-2, LMP-1, and MMP9 expressions were detected in 57 biopsies of primary NPC by immunohistochemistry. The presence of Epstein-Barr virus (EBV) was determined using EBER in situ hybridization, and intratumoral microvessels were highlighted by staining endothelial cells for anti-CD34. The correlations with immunostainings and clinicopathological factors, as well as the follow-up data of patients, were analyzed statistically. Strong expression of PAR-2 in 61.4% (35/57) of the biopsies was correlated with extensive lymph node metastasis and advanced stage of NPC. The patients with PAR-2/LMP-1 or PAR-2/MMP9 dual high-expression tumors had a significant worse prognosis than those with single protein high expression and dual low or negative expression tumors (P=0.013 and 0.004, respectively). Angiogenesis in the tumor is related to overall survival of NPC patients (P=0.001), and exhibits strong PAR-2 expression or LMP-1 expression in tumors associated with increased intratumoral microvessel density (P=0.026 and 0.006, respectively). PAR-2 is a possible mediator cooperating with LMP-1 and MMP9 to influence the progression of NPC by inducing angiogenesis and promoting lymph node metastasis.