Overexpression of β-Adrenergic Receptors and the Suppressive Effect of β2-Adrenergic Receptor Blockade in Oral Squamous Cell Carcinoma

Blocking β2-AR and Inhibiting COX-2: A Promising Approach to Suppress OSCC Development

OBJECTIVES

β2-adrenergic receptor (β2-AR) and cyclooxygenase-2 (COX-2) are overexpressed in various malignant tumours including oral squamous cell carcinoma (OSCC), suggesting that they may contribute to the development of OSCC. This study aims to investigate the potential synergistic effect of β2-AR blockade and COX-2 inhibition on suppressing the development of OSCC.

METHODS

Effects of blocking β2-AR and inhibiting COX-2 on migration and invasion of OSCC cells were detected by wound-healing assay and transwell invasion assay. Western blot and enzyme-linked immunosorbent assay (ELISA) were used to detect the expression of genes related to the progression of OSCC. In vivo, OSCC xenograft models were established to evaluate the effect of combined treatment on survival time, tumour size, and submandibular lymph node metastasis. Immunohistochemistry, Western blot, and ELISA were used to detect the expression of invasion and metastasis relative genes.

RESULTS

In vitro, blocking β2-AR or inhibiting COX-2 alone could suppress invasion and metastasis of OSCC cells, and suppression with combined treatment was more significant. Expression of genes related to invasion and metastasis, including EGFR, TGF-β1, IL-1β, MMP2, and VEGFA, were downregulated significantly, especially in the combined treatment group. In vivo, the combined treatment could significantly prolong survival time in tumour-bearing mice and inhibit the growth of tumours. Furthermore, submandibular lymph node metastasis was less in the combined treatment group, and expression of the abovementioned genes was also downregulated.

CONCLUSIONS

The combination of β2-AR blockade and COX-2 inhibition can significantly suppress the development of OSCC via downregulating EGFR, TGF-β1, IL-1β, MMP2, and VEGFA. Findings suggest that the combined use of a β2-AR blocker and a COX-2 inhibitor could be a promising adjuvant therapy in OSCC. Both drugs are commonly prescribed, and their safety and efficacy are well established. Their use in adjuvants in OSCC should therefore be promoted in clinical practice.

A neural-related gene risk score for head and neck squamous cell carcinoma

OBJECTIVES

This study aimed to establish a neural-related gene risk score (NRGRS) for the prediction of head and neck squamous cell carcinoma prognosis and explore its predictive value on the benefit of immune checkpoint inhibitor therapy.

METHODS

Based on the transcriptome data of HNSCC patients (n = 546) from The Cancer Genome Atlas database, 37 neural-related hub genes were identified by weighted gene co-expression network analysis. Four genes (ITGA5, PYGM, GNG7 and ATP2A3) were identified to construct NRGRS using Lasso-Cox regression method based on the derivation cohort and validated in the Gene Expression Omnibus cohort (n = 109). The survival analysis was performed to validate the prognostic value of NRGRS and immune characteristics in NRGRS-defined subgroups were analyzed.

RESULTS

NRGRS-high patients had a worse overall survival than NRGRS-low patients. Tumors with high NRGRS were more likely to have high infiltration of naive CD4+ T cells, M0, M2 macrophages and resting mast cells, which illustrated suppressive immunity and less benefit from immunotherapy therapy.

CONCLUSION

NRGRS strongly correlates with survival and is a promising biomarker to predict immunotherapy benefits for head and neck cancer patients. This study provides evidence for the potential correlation between neural-related transcriptome alteration and immune activity.

Lingual Denervation Improves the Efficacy of Anti-PD-1 Immunotherapy in Oral Squamous Cell Carcinomas by Downregulating TGFβ Signaling

PURPOSE

Intratumoral nerve infiltration relates to tumor progression and poor survival in oral squamous cell carcinoma (OSCC). How neural involvement regulates antitumor immunity has not been well characterized. This study aims to investigate molecular mechanisms of regulating tumor aggressiveness and impairing antitumor immunity by nerve-derived factors.

EXPERIMENTAL DESIGN

We performed the surgical lingual denervation in an immunocompetent mouse OSCC model to investigate its effect on tumor growth and the efficacy of anti-PD-1 immunotherapy. A trigeminal ganglion neuron and OSCC cell coculture system was established to investigate the proliferation, migration, and invasion of tumor cells and the PD-L1 expression. Both the neuron-tumor cell coculture in vitro model and the OSCC animal model were explored.

RESULTS

Lingual denervation slowed down tumor growth and improved the efficacy of anti-PD-1 treatment in the OSCC model. Coculturing with neurons not only enhanced the proliferation, migration, and invasion but also upregulated TGFβ-SMAD2 signaling and PD-L1 expression of tumor cells. Treatment with the TGFβ signaling inhibitor galunisertib reversed nerve-derived tumor aggressiveness and downregulated PD-L1 on tumor cells. Similarly, lingual denervation in vivo decreased TGFβ and PD-L1 expression and increased CD8+ T-cell infiltration and the expression of IFNγ and TNFα within tumor.

CONCLUSIONS

Neural involvement enhanced tumor aggressiveness through upregulating TGFβ signaling and PD-L1 expression in OSCC, while denervation of OSCC inhibited tumor growth, downregulated TGFβ signaling, enhanced activities of CD8+ T cells, and improved the efficacy of anti-PD-1 immunotherapy. This study will encourage further research focusing on denervation as a potential adjuvant therapeutic approach in OSCC.

SIGNIFICANCE

This study revealed the specific mechanisms for nerve-derived cancer progression and impaired antitumor immunity in OSCC, providing a novel insight into the cancer-neuron-immune network as well as pointing the way for new strategies targeting nerve-cancer cross-talk as a potential adjuvant therapeutic approach for OSCC.

Expression pattern and clinical significance of beta 2-adrenergic receptor in oral squamous cell carcinoma: an emerging prognostic indicator and future therapeutic target

PURPOSE

Beta 2-Adrenergic Receptor (β2-AR) is significantly overexpressed in various types of malignancies, which is associated with the worst prognosis. However, the role of β2-AR in oral cancer is not well identified. The present study aimed at investigating the β2-AR gene expression and its significance in relation with the clinicopathological features and overall survival of oral squamous cell carcinoma (OSCC) patients.

METHODS

Immunohistochemistry, western blot and quantitative real-time PCR techniques were used to analyze β2-AR protein and mRNA levels in a total of 65 histopathologically confirmed OSCC tissues (case group) and 65 normal tissues (control group) from the oral cavity.

RESULTS

Out of the total of 65 OSCC tissues, 41 tissues (63.1%) exhibited  high expression  for β2-AR protein. Percent positivity and relative density (mean ± SD) of protein were higher in the case group as compared to the control group (positivity 40.31 ± 3.01 vs. 20.46 ± 1.93, p < 0.001; density 2.77 ± 1.17 vs. 1.28 ± 0.37, p < 0.001). In addition, β2-AR mRNA level was also upregulated in patients compared to the controls (2.36 ± 1.30 vs. 1.09 ± 0.42, p < 0.001) and showed a positive correlation with immunostaining of protein in OSCC (r = 0.48, p = 0.011). High β2-AR protein expression was significantly associated with multiple risk habits (p = 0.045), histological differentiation (p = 0.013), clinical TNM stages (p = 0.014), and poor survival (p = 0.006) of patients. In the Cox proportional hazards model, β2-AR was identified as a prognostic biomarker of OSCC (p = 0.047).

CONCLUSION

β2-AR protein level is identified as an independent significant prognostic factor in patients with oral carcinoma.

ADRB2 is a potential protective gene in breast cancer by regulating tumor immune microenvironment

Background

Breast cancer (BRCA) is the leading cause of cancer death among females. Studies suggested that β-adrenoceptors involved in tumor progression by regulating immune system. However, how ADRB2 affects the immune infiltration in BRCA is still being unraveled.

Methods

Expressions of ADRB2 in multiple tissues, cancers and blood cells were analyzed by using the Human Protein Atlas and UALCAN database. Expression differentiation of ADRB2 in tumor microenvironment (TME) of BRCA was detected in TISCH database. Correlations between ADRB2 and immune cell infiltration were analyzed by TIMER 2.0, and co-expression genes of ADRB2 were obtained from the cBioPortal website. Functional enrichment analyses and protein-protein interactions were constructed as well. Finally, the potential mechanisms of ADRB2 and candidate drugs targeting BRCA were discussed by using the Metascape, STITCH and Cmap tools.

Results

ADRB2 was significantly down-regulated in BRCA, and lower ADRB2 expression often resulted in worse prognosis in BRCA patients. ADRB2 was mainly expressed in breast tissue and blood. Among blood cell subtypes and TME of BRCA, ADRB2 was specifically expressed in T cell subtypes. Also, ADRB2 expression level was positively correlated with the infiltration levels of immune cells such as CD4+ T cell, CD8+ T cell, Tγδ and myeloid DC while negatively correlated with Treg, Tfh and myeloid-derived suppressor cell. Furthermore, functional enrichment analyses revealed that most enriched pathways were immune-related, especially in T cell-related pathways. Also, transcription factors (TFs) analyses showed that most downstream TFs regulated by ADRB2 were immune-related, and most candidate drugs had promising anti-tumor effects.

Conclusions

In conclusion, ADRB2 was a potential protective gene in BRCA, and it might play a vital role in regulating immune responses. The expression level of ADRB2 was positively correlated with immune cells infiltration in BRCA, especially for T cells. Therefore, ADRB2 would be a target for boosting immunotherapy effects in BRCA.

β2-adrenergic receptor expression and the effects of norepinephrine and propranolol on various head and neck cancer subtypes

The present study aimed to investigate expression of β2-adrenergic receptor (AR), the effect of the stress-related neurotransmitter norepinephrine (NE) on cell viability, proliferation and the therapeutic effect of propranolol, which is a typical β-blocker in various type of head and neck cancers for the first time. The β2-AR expression was investigated using immunohistochemistry and an immunoreactive scoring (IRS) system in 57 different head and neck cancer specimens, and reverse transcriptase-polymerase chain reaction and western blotting in four head and neck cancer cell lines (HNCCLs). Cell viability and proliferation assays were performed using 0, 1, 5 and 10 µM of NE and 1 µM of propranolol in four HNCCLs. The expression of β2-AR was positive in the majority of head and neck cancer tissues (55/57, 96.5%); however, it was significantly higher in oral cavity cancer than in pharyngeal cancer (median IRS: 9 vs. 3; P<0.001). All HNCCLs exhibited β2-AR expression, with a higher expression level detected in the oral cavity cancer cell line than in the others. NE stimulated viability (oral cavity, 206%; larynx, 156%; pharynx, 130%; nasal cavity, 137%; 10 µM NE) and proliferation (124, 176, 131 and 127%, respectively) in a dose-dependent manner in all HNCCLs. Conversely, propranolol attenuated such viability (55, 42, 18 and 22%, respectively) and proliferation (22, 40, 61 and 48%, respectively). In conclusion, the viability and proliferation of various head and neck cancers may be directly stimulated by stress and this may be attenuated by β-blockers.