The current advances and future directions of PD-1/PD-L1 blockade in head and neck squamous cell carcinoma (HNSCC) in the era of immunotherapy

PD-1 inhibitors combined with chemotherapy versus chemotherapy alone: efficacy and prognostic analysis in recurrent metastatic nasopharyngeal carcinoma

OBJECTIVE

To evaluate the prognostic value of combining PD-1 inhibitors (toripalimab or karelizumab) with chemotherapy for treating recurrent or metastatic nasopharyngeal carcinoma (R/M NPC).

METHODS

This study retrospectively analyzed 142 patients with R/M NPC diagnosed from January 2018 to January 2022. Patients were divided into PD-1 inhibitor combined with chemotherapy group (53 patients) and chemotherapy alone group (89 patients) according to the treatment regimen. Objective remission rate (ORR), progression-free survival (PFS), and treatment-related toxicity were evaluated in both groups.

RESULTS

The overall response rate (P=0.006) and objective remission rate (ORR) (P=0.002) were significantly higher in the combination chemotherapy group than in the chemotherapy-alone group. The incidences of hypothyroidism (P<0.001) and reactive capillary hyperplasia (P<0.001) were significantly higher in the combination chemotherapy group than in the chemotherapy-alone group. Cox regression analysis showed that treatment regimen (P<0.001), age (P<0.001), treatment duration (P=0.002), and number of treatment lines (P=0.034) were independent prognostic factors affecting patients' PFS. The prediction model constructed based on these prognostic factors had high accuracy in predicting 1-year and 2-year PFS (AUC 0.746 and 0.760, respectively).

CONCLUSION

PD-1 inhibitors in combination with chemotherapy significantly improved the ORR and median PFS of patients with R/M NPC, while maintaining a favorable safety profile. Treatment regimen, age, number of lines and cycle of therapy were important independent prognostic factors for improving PFS in patients.

Macrophages: plastic participants in the diagnosis and treatment of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) rank among the most prevalent types of head and neck cancer globally. Unfortunately, a significant number of patients receive their diagnoses at advanced stages, limiting the effectiveness of available treatments. The tumor microenvironment (TME) is a pivotal player in HNSCC development, with macrophages holding a central role. Macrophages demonstrate diverse functions within the TME, both inhibiting and facilitating cancer progression. M1 macrophages are characterized by their phagocytic and immune activities, while M2 macrophages tend to promote inflammation and immunosuppression. Striking a balance between these different polarization states is essential for maintaining overall health, yet in the context of tumors, M2 macrophages typically prevail. Recent efforts have been directed at controlling the polarization states of macrophages, paving the way for novel approaches to cancer treatment. Various drugs and immunotherapies, including innovative treatments based on macrophages like engineering macrophages and CAR-M cell therapy, have been developed. This article provides an overview of the roles played by macrophages in HNSCC, explores potential therapeutic targets and strategies, and presents fresh perspectives on the future of HNSCC treatment.

Immune checkpoint CD161/LLT1-associated immunological landscape and diagnostic value in oral squamous cell carcinoma

An active host adaptive response is characterized by the existence of programmed cell death protein 1 (PD-1)+ /IFN-γ+ cytotoxic T cells and IFN-γ-induced PD-L1+ tumor cells (TCs), which predicts high response rate to anti-PD-1/L1 therapy. Recently, CD161 and its ligand LLT1 (CLEC2D) have been identified as an emerging checkpoint for immunotherapy. Clarifying its heterogeneous clinical expression pattern and its immune landscape is a prerequisite for maximizing the response rate of CD161 blockade therapy in a specific population of oral squamous cell carcinoma (OSCC) patients. Here, we investigated the expression pattern of CD161/LLT1 and its association with major immunocytes (T cells, B cells, NK cells, and macrophages) by multiplex immunofluorescence, immunohistochemistry, and flow cytometry in 109 OSCC tissues and 102 peripheral blood samples. TCs showed higher LLT1 levels than tumor infiltrating lymphocytes (TILs), whereas CD161 was highly expressed in CD8+ T cells at the tumor front, which was decreased in paracancerous tissue. High expression of TC-derived LLT1 (LLT1TC ) conferred poor clinical outcomes, whereas higher CD161+ and LLT1+ TILs were associated with better prognosis. Meanwhile, patients with high LLT1TC showed a decreased ratio of CD8+ /Foxp3+ T cells in situ, but CD161+ TILs correlated with more peripheral CD3+ T cells. Interestingly, treatment of OSCC patients with nivolumab (anti-PD-1) could restore tumoral CD161/LLT1 signal. Furthermore, an OSCC subgroup characterized by high LLT1+ TCs and low CD161+ CD8+ T cells showed fewer peripheral T cells and a higher risk of lymph node metastasis, leading to a shorter 5-year survival time (29%). More LLT1TC at the invasive front was another risk characteristic of exhausted T cells. In conclusion, in view of this heterogeneity, the LLT1/CD161 distribution pattern should be determined before CD161-based immunotherapy.

Induction Toripalimab and Chemotherapy for Organ Preservation in Locally Advanced Laryngeal and Hypopharyngeal Cancer: A Single-Arm Phase II Clinical Trial

PURPOSE

The aim of this study was to assess the efficacy, toxicities, and potential role of larynx preservation of induction chemotherapy combined with programmed cell death protein 1 (PD-1) inhibitor in locally advanced laryngeal and hypopharyngeal cancer.

PATIENTS AND METHODS

This is a single-arm phase II study. Patients with histopathologically confirmed, resectable locally advanced laryngeal/hypopharyngeal squamous cell carcinoma and Eastern Cooperative Oncology Group Performance Status 0-1 were eligible. Three cycles of induction chemotherapy (paclitaxel 175 mg/m2 d1, cisplatin 25 mg/m2 d1-3) combined with PD-1 inhibitor (toripalimab 240 mg d0) were administered. Response assessment was performed after induction chemoimmunotherapy using RECIST 1.1 criteria. Patients with a complete/partial response of the primary tumor received concurrent chemoradiation, followed by maintenance therapy of toripalimab. Otherwise, patients were referred to surgery, followed by adjuvant (chemo) radiation and maintenance therapy of toripalimab. The primary endpoint is a larynx preservation rate at 3 months postradiation.

RESULTS

Twenty-seven patients were enrolled. Most cases exhibited stage IV disease (81.5%), with T4 representing 37.0%. Five patients underwent pretreatment tracheostomy because of impaired larynx function. Overall response rate of induction chemoimmunotherapy was 85.2%. At 3 months postradiation, the larynx preservation rate was 88.9%. With a median follow-up of 18.7 months, the 1-year overall survival rate, progression-free survival rate, and larynx preservation rate were 84.7%, 77.6%, and 88.7%, respectively. When excluding those with pretreatment tracheostomy, the 1-year larynx preservation rate was 95.5%. Exploratory analysis revealed that relapse correlated with enrichment of RNA signature of hypoxia and M2 macrophage-associated genes.

CONCLUSIONS

Induction toripalimab combined with chemotherapy provided encouraging activity, promising larynx preservation rate and acceptable toxicity in this cohort of extensively locally advanced laryngeal and hypopharyngeal cancer.

Efficacy and safety of immune checkpoint inhibitors in recurrent or metastatic head and neck squamous cell carcinoma: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Immune checkpoint inhibitors (ICIs) showed antitumor activity for recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, the results from different studies were controversial.

METHODS

Online databases were searched for randomized clinical trials (RCTs) evaluating ICIs for R/M HNSCC. The characteristics of the studies and the results of overall survival (OS), progression-free survival (PFS), objective response rate (ORR), treatment-related adverse events (TRAEs) were extracted.

RESULTS

A total of 4936 patients from eight studies were included. Anti-PD1/PDL1 monotherapy significantly improved OS in total population (hazard ratio, HR, 0.87, 95% CI, 0.79-0.95, p = 0.003) and PD-L1 high expression patients (HR, 0.71, 95% CI, 0.55-0.90, p = 0.006) with significant lower incidence of any grade TRAEs (odds ratio, OR, 0.16, 95% CI, 0.07-0.37, p < 0.00001) and Grades 3-5 TRAEs (OR, 0.18, 95% CI, 0.10-0.33, p < 0.0001) compared with standard of care (SOC); however, the pooled results of PFS and ORR were not significant different. PD1/PDL1 inhibitors plus CTLA4 inhibitors did not improve OS, PFS, ORR compared with SOC or ICIs monotherapy; however, the incidence of Grades 3-5 TRAEs was significant higher compared with ICIs monotherapy (OR, 1.80, 95% CI, 1.34-2.41, p = 0.0001).

CONCLUSIONS

Anti-PD1/PDL1 monotherapy could improve OS for R/M HNSCC with significant lower incidence of TRAEs compared with SOC. PD1/PDL1 inhibitors plus CTLA4 inhibitors showed no more benefit compared with both SOC and ICIs monotherapy, but the incidence of Grades 3-5 TRAEs was significant higher compared with ICIs monotherapy.

Advantages of the Combinatorial Molecular Targeted Therapy of Head and Neck Cancer-A Step before Anakoinosis-Based Personalized Treatment

The molecular initiators of Head and Heck Squamous Cell Carcinoma (HNSCC) are complex. Human Papillomavirus (HPV) infection is linked to an increasing number of HNSCC cases, but HPV-positive tumors generally have a good prognosis. External factors that promote the development of HPV-negative HNSCC include tobacco use, excessive alcohol consumption, and proinflammatory poor oral hygiene. On a molecular level, several events, including the well-known overexpression of epidermal growth factor receptors (EGFR) and related downstream signaling pathways, contribute to the development of HNSCC. Conventional chemotherapy is insufficient for many patients. Thus, molecular-based therapy for HNSCC offers patients a better chance at a cure. The first molecular target for therapy of HNSCC was EGFR, inhibited by monoclonal antibody cetuximab, but its use in monotherapy is insufficient and induces resistance. This article describes attempts at combinatorial molecular targeted therapy of HNSCC based on several molecular targets and exemplary drugs/drug candidates. The new concept of anakoinosis-based therapy, which means treatment that targets the intercellular and intracellular communication of cancer cells, is thought to be the way to improve the clinical outcome for HNSCC patients. The identification of a link between molecular targeted therapy and anakoinosis raises the potential for further progress in HPV-negative HNSCC therapy.

Involvement of KLRK1 in immune infiltration of head and neck squamous cell carcinoma correlates with favorable prognosis

Head and neck squamous cell carcinoma (HNSCC) is a malignancy commonly found in the head and neck region, with a low 5-year survival rate. Although immunotherapy has made significant progress, its efficacy in HNSCC treatment remains unsatisfactory. Killer cell lectin-like receptor K1 (KLRK1), a marker highly expressed in immune cells, can bind to its ligands expressed by cancer cells to exert its antitumor effect. However, the role of KLRK1 in HNSCC has yet to be studied extensively. This study aimed to explore the involvement of KLRK1 in immune infiltration of HNSCC and its correlation with prognosis. We analyzed KLRK1 expression data from the Cancer Genome Atlas database. The relationship between KLRK1 and immune cell infiltration has also been investigated. Finally, we analyzed the association between the expression of KLRK1 and its ligands and the prognosis of patients with HNSCC. We found that KLRK1 was highly expressed in HNSCC and correlated with better prognosis. KLRK1 expression was correlated with age, histological grade, HPV infection, pT, pN, pTNM stage, primary site, and survival status. High expression levels of KLRK1 have been linked to high levels of immune cell infiltration, particularly CD4/8 (+) T lymphocytes. Among the ligands of KLRK1, UL16 binding protein (ULBP) 1-3 showed high expression, which was associated with an increased risk of death. Notably, the expression of KLRK1 was negatively correlated with ULBP1-3. Patients with high levels of ULBP2/3 expression in tonsil carcinoma had poorer prognosis than those with low levels (P < .01), whereas ULBP1 expression levels had no significant effect on tonsil carcinoma prognosis (P = .770). The expression levels of ULBP1/3 were correlated with worse prognosis in patients with laryngeal cancer (P < .05), whereas there was no significant correlation between ULBP2 expression levels and overall survival (P = .269). Our study revealed that KLRK1 is highly expressed in HNSCC and is associated with a better prognosis and immune infiltration. Patients with high expression of KLRK1 ligands exhibited worse prognoses, possibly because of the expression of more soluble ligands.