Enhancing the immune stimulatory effects of cetuximab therapy through TLR3 signalling in Epstein-Barr virus (EBV) positive nasopharyngeal carcinoma.

Cetuximab immunotherapy targeting the epidermal growth factor receptor (EGFR) has been used to treat nasopharyngeal cancer (NPC) with some success. Therefore, combining an immune adjuvant to boost the immune microenvironment may improve its clinical efficacy. Herein, we investigate the immune-stimulatory effects of Poly-ICLC (a TLR3 agonist) in enhancing cetuximab-based immunotherapy and correlate these responses with FcÉ£RIIIa (V158F) or TLR3 single nucleotide polymorphisms (SNPs- L412F and C829T) expressed on immune effector cells. We observed high levels of TLR3 mRNA in NPC cells; and both TLR3 and EGFR expression were unaffected by Poly-ICLC treatment. Cetuximab plus Poly-ICLC significantly enhanced NK-mediated ADCC through up-regulation of CD107a and Granzyme B expression. This effect was independent of FcÉ£RIIIa-V158F and TLR3-L412F or TLR3-C829T polymorphisms expressed on NK cells. Additionally, IFN-É£ expression and secretion were doubled following cetuximab plus poly-ICLC treatment; compared to either treatment alone. This effect was independent of TLR3 polymorphisms. Consequentially, adaptive immune responses were also seen with increased DC maturation (CD83), co-stimulatory molecules expression (CD80 and CD86) and increased frequency of EGFR-specific CD8 + T cells following Poly-ICLC treatment. The percentage of CD80+ CD83+ and CD83+ CD86+ DC was highest in the Poly-ICLC plus cetuximab group, compared to either treatment alone. These results demonstrate the effectiveness of Poly-ICLC in enhancing both cetuximab-mediated innate and adaptive anti-tumor immunity against NPC, which is independent of FcÉ£RIIIa-158, TLR3-L412F or TLR3-C829T polymorphisms. Additionally, Poly-ICLC does not downregulate EGFR expression on NPC cells and hence, will not dampen cetuximab anti-tumor activity.

Cellular-based immunotherapy in Epstein-Barr virus induced nasopharyngeal cancer.

Undifferentiated Nasopharyngeal carcinoma (NPC) is ubiquitously identified with the Epstein-Barr virus (EBV), making this cancer a suitable candidate for cellular-based immunotherapy (CBI) due to its expression of potentially targetable tumor-associated viral antigens. Various preclinical and clinical studies have explored the use of cytotoxic T cells (CTLs), tumor-infiltrating lymphocytes (TILs), natural killer (NK) cells, and dendritic cells (DCs) in the treatment of both refractory and locally advanced NPC with some success. Notably, immune-mediated antitumor effects were observed even in heavily pre-treated NPC patients, suggesting potential clinical benefit of CBI in this group of patients. These immune anti-tumor effects may be even more clinically evident when used as a first-line treatment, since there may not be an intense immunosuppressive environment which is typically encountered in refractory cancer patients. Additionally, CBI may exert an effect in priming the immune system and diminishing the cancer's acquired resistance to exert a more robust response to previously failed chemotherapy. Although these results are encouraging, further refinements of clinical protocols to boost anti-tumor response and benefit a larger subset of patients proved necessary. Herein, we aim to review the rational of developing CBI in EBV-induced NPC and summarize its current applications in clinical studies.

High-risk HPV genotypes and P16INK4a expression in a cohort of head and neck squamous cell carcinoma patients in Singapore.

Human papillomavirus (HPV), especially HPV16 genotype, is associated with oropharyngeal squamous cell carcinoma (OPSCC). We aim to determine the prevalence and characterize the high-risk (HR)-HPV genotypes in head and neck SCC (HNSCC) in a South-East Asian multi-ethnic society in Singapore and examine its prognostic significance.159 HNSCC archival tissue samples were retrieved and tumour DNA was screened for 18 HR-HPV genotypes using a PCR-based assay (Qiagen, digene HPV genotyping RH test). P16 protein overexpression was identified using immunohistochemistry (IHC). Statistical correlation between clinical outcomes were performed between HPV-positive and negative HNSCC patients.Six HR-HPVs (HPV16, 18, 31, 45, 56, 68) were detected in 90.6% of HNSCC; and 79.9% had multiple HPV genotypes detected. HPV31 and HPV45 were the most prevalent (79.2% and 87.4%, respectively); and HPV16 was predominantly found in OPSCC (p < 0.001). HPV-DNA PCR assay yielded a high sensitivity (96%) but low specificity (11%) when compared to p16 immunohistochemistry as the reference standard.P16-positive HNSCC was predominantly observed in OPSCC (73.7%; p = 0.005); and p16-positive OPSCC exhibited improved overall survival compared to p16-negative OPSCC (p = 0.022). Similarly, smoking and alcohol consumption were poor prognostic factors of overall survival (p = 0.007; p = 0.01) in OPSCC patients.HR-HPVs were identified in 90.6% of HNSCC patients using the HPV-DNA PCR assay. This test had a poor specificity when compared to p16 IHC; making it an unreliable detection technique in selecting patients for radiation dose de-escalation treatment protocol. P16-positive tumor was predominantly found in the oropharynx these patients demonstrated better overall survival than those with p16-negative OPSCC.