Head and neck cancer: the role of anti-EGFR agents in the era of immunotherapy

Deciphering the complex landscape of post-translational modifications on PKM2: Implications in head and neck cancer pathogenesis

In the vast landscape of human health, head and neck cancer (HNC) poses a significant health burden globally, necessitating the exploration of novel diagnostics and therapeutics. Metabolic alterations occurring within tumor microenvironment are crucial to understand the foundational cause of HNC. Post-translational modifications (PTMs) have recently emerged as a silent foe exerting a significantly heightened influence on various aspects of the biological processes associated with the onset and advancement of cancer, particularly in the context of HNC. There are numerous targets involved in HNC but recently, the enzyme pyruvate kinase M2 (PKM2) has come out as a hot target due to its involvement in glycolysis resulting in metabolic reprogramming of cancer cells. Various PTMs have been reported to affect the structure and function of PKM2 by modulating its activity. This review aims to investigate the impact of PTMs on the interaction between PKM2 and several signaling pathways and transcription factors in the context of HNC. These interactions possess significant ramification for cellular proliferation, apoptosis, angiogenesis and metastasis. This review primarily explores the role of PTMs influencing PKM2 and its involvement in tumor development. While acknowledging the significance of PKM2 interactions with other tumor regulators, the emphasis lies on dissecting PTM-related mechanisms rather than solely scrutinizing individual regulators. It lays the framework for the development of more sophisticated diagnostic tools and uncovers exciting possibilities for precision medicine essential for effectively addressing the complexity of this malignancy in a precise and focused manner.

Radioresistance or/and radiosensitivity of head and neck squamous cell carcinoma: biological angle

OBJECTIVE

This narrative review aimed to compile and summarize clinically relevant literature in radiation therapy and to discuss the potential in radioresistant and radiosensitive head and neck squamous cell carcinoma (HNSCC).

METHODS AND MATERIALS

Google Scholar, PubMed, and the Cochrane Library were retrieved using combined key words such as "radiotherapy" and "head and neck cancer." Search strings additionally queried were "radioresistant," "radiosensitive," "head and neck region," "squamous cell carcinoma," in combination with Boolean operators 'AND' and 'OR.' Subsequently, the resulting publications were included for review of the full text.

RESULTS

Radiotherapeutic responses currently in clinical observation referred to HNSCC scoping were selected into this review. The compiled mechanisms were then detailed concerning on the clinical significance, biological characteristics, and molecular function.

CONCLUSIONS

Brachytherapy or/and external-beam radiotherapy are crucial for treating HNSCC especially the early stage patients, but in some patients with locally advanced tumors, their outcome with radiation therapy is poor due to obvious radioresistance. The curative effects mainly depend on the response to radiation therapy so an updated review is needed to optimize further applications in HNSCC radiotherapy.

The effects of re-irradiation on the chemical and morphological properties of permanent teeth

This study aimed to assess the in vitro effects of re-irradiation on enamel and dentin properties, simulating head and neck cancer radiotherapy retreatment. Forty-five human permanent molars were classified into five groups: non-irradiated; irradiated 60 Gy, and re-irradiated with doses of 30, 40, and 50 Gy. Raman spectroscopy, scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were employed for analysis. Raman spectroscopy assessed intensity, spectral area, and specific peaks comparatively. Statistical analysis involved Kolmogorov-Smirnov and One-Way ANOVA tests, with Tukey's post-test (significance level set at 5%). Significant changes in irradiated, non-irradiated, and re-irradiated enamel peaks were observed, including phosphate (438 nm), hydroxyapatite (582 nm), phosphate (960 nm), and carbonate (1070 nm) (p < 0.05). Re-irradiation affected the entire tooth (p > 0.05), leading to interprismatic region degradation, enamel prism destruction, and hydroxyapatite crystal damage. Dentin exhibited tubule obliteration, crack formation, and progressive collagen fiber fragmentation. EDX revealed increased oxygen percentage and decreased phosphorus and calcium post-reirradiation. It is concluded that chemical and morphological changes in irradiated permanent teeth were dose-dependent, exacerbated by re-irradiation, causing substantial damage in enamel and dentin.

Combining Anti-epidermal Growth Factor Receptor (EGFR) Therapy with Immunotherapy in Metastatic Colorectal Cancer (mCRC)

INTRODUCTION

Monoclonal antibodies binding the EGFR, such as cetuximab and panitumumab, have been extensively used as targeted therapy for the treatment of mCRC. However, in clinical practice, it has been found that these treatment options have some limitations and fail to fully exploit their immunoregulatory activities. Meanwhile, because of the limited effects of current treatments, immunotherapy is being widely studied for patients with mCRC. However, previous immunotherapy trials in mCRC patients have had unsatisfactory outcomes as monotherapy. Thus, combinatorial treatment strategies are being researched.

AREAS COVERED

The authors retrieved relevant documents of combination therapy for mCRC from PubMed and Medline. This review elaborates on the knowledge of immunomodulatory effects of anti-EGFR therapy alone and in combination with immunotherapy for mCRC.

EXPERT OPINION

Although current treatment options have improved median overall survival (OS) for advanced disease to 30 months, the prognosis remains challenging for those with metastatic disease. More recently, the combination of anti-EGFR therapy with immunotherapy has been shown activity with complementary mechanisms. Hence, anti-EGFR therapy in combination with immunotherapy may hold the key to improving the therapeutic effect of refractory mCRC.

Rethinking treatment paradigms: Neoadjuvant therapy and de-escalation strategies in HPV-positive head and neck cancer

Head and neck cancer (HNC) is the 6th most common cancer across the world, with a particular increase in HNC associated with human papilloma virus (HPV) among younger populations. Historically, the standard treatment for this disease consisted of combined surgery and radiotherapy or curative platinum-based concurrent chemoradiotherapy, with associated long term and late toxicities. However, HPV-positive HNC is recognized as a unique cancer subtype, typically with improved clinical outcomes. As such, treatment de-escalation strategies have been widely researched to mitigate the adverse effects associated with the current standard of care without compromising efficacy. These strategies include treatment de-escalation, such as novel surgical techniques, alternative radiation technologies, radiation dose and volume reduction, as well as neoadjuvant chemotherapies, immunotherapies, and combined therapies. Although these therapies show great promise, many of them are still under investigation due to hesitation surrounding their widespread implementation. The objective of this review is to summarize the most recent progress in de-escalation strategies and neoadjuvant therapies designed for HPV-positive HNC. While specific treatments may require additional research before being widely adopted, encouraging results from recent studies have highlighted the advantages of neoadjuvant chemotherapy and immunotherapy, as well as radiation and surgical de-escalation approaches in managing HPV-positive HNC.

A radiobiological perspective on radioresistance or/and radiosensitivity of head and neck squamous cell carcinoma

Background

This article aimed to compile and summarize clinically relevant literature in radiation therapy, and to discuss the potential in radioresistant and radiosensitive head and neck cancer.

Study Design

Narrative review.

Materials and methods

Google Scholar, PubMed and the Cochrane Library were retrieved using combined key words such as "radiotherapy" and "head and neck cancer". Search strings additionally queried were "radioresistant", "radiosensitive", "head and neck region", "squamous cell carcinoma", in combination with Boolean Operators 'AND' and 'OR'. Subsequently, the resulting publications were included for review of the full text.

Results

Radiotherapeutic response currently in clinical observation referred to HNSCC scoping were selected into this review. The compiled mechanisms were then detailed concerning on the clinical significance, biological characteristics, and molecular function.

Conclusions

Brachytherapy or/and external-beam radiotherapy are crucial for treating HNSCC, especially the early stage patients, but in patients with locally advanced tumors, their outcome with radiation therapy is poor due to obvious radioresistance. The curative effects mainly depend on the response of radiation therapy, so an updated review is needed to optimize further applications in HNSCC radiotherapy.

Exploring long-term responses to immune checkpoint inhibitors in recurrent and metastatic head and neck squamous cell carcinoma

OBJECTIVES

Immune checkpoint inhibitors (ICI) have introduced a new era in the treatment of recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC). Optimal duration for ICI therapy is still unclear and the long-term outcomes and toxicity in patients responding to these therapies warrant further exploration. This study attempts to identify the clinical and biological determinants of a durable response and evaluate outcomes following ICI treatment discontinuation.

MATERIALS AND METHODS

A retrospective review of 181 patients treated with ICI for R/M HNSCC was conducted. Long-term responders were defined as patients who sustained disease control at least two years after initiating ICI therapy. We compared clinical and biological characteristics associated with these long-term responders against the broader treatment population.

RESULTS

10 % of R/M HNSCC patients treated with ICIs demonstrated a durable long-term response. Only three relapses (16 %) occurred after discontinuing ICI treatment in this subset, with a median follow-up of 52 months. Upon retreatment with ICI, two attained a documented response. Extended ICI response was observed even with < 2 years of treatment. 74 % of long-term responders experienced immune-related adverse events (irAEs), 37 % of which severe irAEs. Hypothyroidism was the most frequently reported irAEs. The predictive potential of systemic inflammation indices for clinical response appears to be limited.

CONCLUSIONS

ICI present an optimistic avenue for HNSCC patients, offering substantial long-term responses. The study suggests that a two-year treatment could be optimal and irAEs, although common, are typically mild.

Inhibition of autophagy enhances the anticancer effect of Schisandrin B on head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is among the most common malignant tumors worldwide and has a poor prognosis. Autophagy regulation has been proposed as a possible treatment option for HNSCC. Schisandrin B (Sch B) exerts anticancer effects by regulating apoptosis and autophagy, but the anticancer effect of Sch B in HNSCC remains unclear. This study aimed to investigate the effects of Sch B on human Cal27 HNSCC cells and to further reveal its potential regulatory mechanisms. The anticancer effect of Sch B was evaluated in vitro by flow cytometry, clonogenic assays, and Western blot analysis. The regulatory mechanism of Sch B-induced apoptosis and autophagy was further explored by polymerase chain reaction, luciferase assay, and reactive oxygen species (ROS) detection. The results showed that Sch B significantly induced apoptosis and autophagy in Cal27 cells and that inhibition of autophagy enhanced the apoptotic effect of Sch B on Cal27 cells. Additionally, Sch B-activated autophagy in Cal27 cells was dependent on the nuclear factor-kappa B (NF-κB) pathway, and ROS acted as a regulator of the NF-B pathway. N-acetylcysteine, a scavenger of ROS, inhibited Sch B-dependent autophagy via the NF-κB pathway. Based on the results, Sch B is a potential therapeutic agent for HNSCC and activates the NF-κB pathway by increasing ROS production, which subsequently promotes autophagy in HNSCC cells. Therefore, the strategy of enhancing the anticancer effect of Sch B by inhibiting autophagy deserves further attention.

p63 orchestrates serine and one carbon metabolism enzymes expression in head and neck cancer

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is characterized by high proliferation and limited differentiation. The altered expression of the p53 family members, and specifically of p63, represents a pivotal event in the pathogenesis of HNSCC. Physiologically, p63 affects metabolism through the direct transactivation of the enzyme hexokinase 2, and subsequently controls the proliferation of epithelial cells; nonetheless, its role in cancer metabolism is still largely unclear. The high energetic demand of cancer and the consequent needs of a metabolic reshape, also involve the serine and glycine catabolic and anabolic pathways, including the one carbon metabolism (OCM), to produce energetic compounds (purines) and to maintain cellular homeostasis (glutathione and S-adenosylmethionine).

RESULTS

The involvement in serine/glycine starvation by other p53 family members has been reported, including HNSCC. Here, we show that in HNSCC p63 controls the expression of the enzymes regulating the serine biosynthesis and one carbon metabolism. p63 binds the promoter region of genes involved in the serine biosynthesis as well as in the one carbon metabolism. p63 silencing in a HNSCC cell line affects the mRNA and protein levels of these selected enzymes. Moreover, the higher expression of TP63 and its target enzymes, negatively impacts on the overall survival of HNSCC patients.

CONCLUSION

These data indicate a direct role of p63 in the metabolic regulation of HNSCC with significant clinical effects.

Nuclear epidermal growth factor receptor as a therapeutic target

Epidermal growth factor receptor (EGFR) is one of the most well-studied oncogenes with roles in proliferation, growth, metastasis, and therapeutic resistance. This intense study has led to the development of a range of targeted therapeutics including small-molecule tyrosine kinase inhibitors (TKIs), monoclonal antibodies, and nanobodies. These drugs are excellent at blocking the activation and kinase function of wild-type EGFR (wtEGFR) and several common EGFR mutants. These drugs have significantly improved outcomes for patients with cancers including head and neck, glioblastoma, colorectal, and non-small cell lung cancer (NSCLC). However, therapeutic resistance is often seen, resulting from acquired mutations or activation of compensatory signaling pathways. Additionally, these therapies are ineffective in tumors where EGFR is found predominantly in the nucleus, as can be found in triple negative breast cancer (TNBC). In TNBC, EGFR is subjected to alternative trafficking which drives the nuclear localization of the receptor. In the nucleus, EGFR interacts with several proteins to activate transcription, DNA repair, migration, and chemoresistance. Nuclear EGFR (nEGFR) correlates with metastatic disease and worse patient prognosis yet targeting its nuclear localization has proved difficult. This review provides an overview of current EGFR-targeted therapies and novel peptide-based therapies that block nEGFR, as well as their clinical applications and potential for use in oncology.

Lysosomal mitochondrial interaction promotes tumor growth in squamous cell carcinoma of the head and neck

Tumor growth and proliferation are regulated by numerous mechanisms. Communication between intracellular organelles has recently been shown to regulate cellular proliferation and fitness. The way lysosomes and mitochondria communicate with each other (lysosomal/mitochondrial interaction) is emerging as a major determinant of tumor proliferation and growth. About 30% of squamous carcinomas (including squamous cell carcinoma of the head and neck, SCCHN) overexpress TMEM16A, a calcium-activated chloride channel, which promotes cellular growth and negatively correlates with patient survival. TMEM16A has recently been shown to drive lysosomal biogenesis, but its impact on mitochondrial function is unclear. Here, we show that (1) patients with high TMEM16A SCCHN display increased mitochondrial content specifically complex I; (2) In vitro and in vivo models uniquely depend on mitochondrial complex I activity for growth and survival; (3) β-catenin/NRF2 signaling is a critical linchpin that drives mitochondrial biogenesis, and (4) mitochondrial complex I and lysosomal function are codependent for proliferation. Taken together, our data demonstrate that LMI drives tumor proliferation and facilitates a functional interaction between lysosomes and mitochondria. Therefore, inhibition of LMI may serve as a therapeutic strategy for patients with SCCHN.

Prevalence of locoregional recurrence and survival post-treatment of head and neck cancers in Africa: a systematic review and meta-analysis

Background

Recurrent cancers of the head and neck are associated with poor survival outcome. Yet, their burden in Africa is not reliably known. We therefore aimed to estimate the prevalence of recurrence and the 5-year overall survival among patients treated for head and neck cancers (HNC) in Africa.

Method

In this systematic review and meta-analysis, we searched four electronic databases (Pubmed, CINAHL, MEDLINE, and Web of Science) and the grey literature for studies reporting the prevalence of HNC recurrence and 5-year overall survival post treatment, published between January 1, 2002, and December 31, 2022. We contacted corresponding authors of relevant studies. Searches were extended to reference lists of review articles and other relevant sources for potentially eligible studies. Each record was assessed for inclusion or exclusion by two independent reviewers. Records with individual-level data on recurrence and survival conducted in Africa were included while exclusion was based on the study design and availability of relevant data. Data were independently extracted by three reviewers from eligible studies, and summary estimates were sought. Our primary outcomes were recurrence and 5-year overall survival of patients who have been treated for HNC, and our secondary outcomes included risk factors, tumor site, squamous cell histology, clinical stage of tumor, and treatment options received. Only records selected for primary outcomes were assessed for secondary outcome data extraction. Random-effects meta-analysis was conducted for each outcome. Meta-regression models were used in addressing sample heterogeneity among the studies. Protocol for this study was registered with PROSPERO, CRD42022372307.

Findings

This systematic review and meta-analysis returned 3998 records, yielding 28 included studies after exclusion. Eighteen studies reported on the prevalence of HNC recurrence while 24 articles reported on the 5-year overall survival. Of the pooled total study population, 7199 (70.5%) of 10,218 patients were males while 2603 (25.5%) were females. We found that the prevalence of HNC recurrence was 15.4% (I² = 96.2%; 95% CI: 9.5-22.3; n = 3214; k = 18), and the 5-year overall survival was 54.4% (I² = 99.5%; 95% CI: 40.1-68.4; n = 9798; k = 24). We also found that the prevalence of smoking and alcohol consumption as risk factors for HNC were 42.6% (I² = 98.8%; 95% CI: 25.2-61.0; n = 4374; k = 15) and 35.8% (I² = 98.9%; 95% CI: 21.7-51.4; n = 4110; k = 11) respectively. The pooled current prevalence for advanced HNC (clinical stages III-IV) was 80.0% (I² = 99.2%; 95% CI: 68.6-89.5; n = 7624; k = 18) compared to 12.2% (I² = 96.4%; 95% CI: 6.2-19.8; n = 7624; k = 18) in early disease (clinical stages I-II).

Interpretation

The results showed significantly high prevalence of cancer recurrence, poor 5-year overall survival and very high prevalence of advanced cancers at time of diagnosis. This study provides robust evidence for strategies towards prompt diagnosis and appropriate management of HNC to improve patients' outcome in the African continent.

Funding

This study was not supported by any funding.

Correlation between 18F-FDG PET/MR parameters with the expression level of epidermal growth factor receptor and the diagnostic value of PET/MR in head and neck squamous cell carcinoma

Objective

To investigate the correlation between parameters of PET/MR and the expression level of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinoma (HNSCC) and to evaluate diagnostic efficacy of independent and combined PET/MR parameters for the expression level of EGFR.

Materials and methods

21 patients who had undergone PET/MR and been proven HNSCC pathologically were included in this retrospective study. The PET/MR sequences included 18-flurodeoxyglucose (¹⁸F-FDG) PET, T1, T2-weighted imaging, DWI, ADC and DCE. Parameters including ADC_mean from DWI, Ktrans, Ve, Kep from DCE, and SUV_mean, SUV_max from PET were obtained. Immunohistochemical method was used to detect the expression level of EGFR. The associations between parameters of PET/MR and EGFR expression level were analyzed by Spearman's analysis. Logistic regression was utilized to establish the diagnostic model of EGFR expression level with PET/MR parameters. The efficacy of the independent and combined diagnostic model for EGFR expression level in HNSCC was analyzed by ROC curve. P value ≤ 0.05 was considered statistically significant.

Results

(1) Expression level of EGFR was correlated to SUV_mean with correlation coefficient of 0.47 (p = 0.05). (2) There was significant difference of SUV_mean between the EGFR high- and low-expression groups (p = 0.02). (3) Combination of PET/MR improved the diagnostic efficacy for expression level of EGFR, with AUC = 0.93.

Conclusion

There were different degrees of correlation between PET/MR parameters and EGFR expression level in HNSCC. Combination of PET/MR might improve diagnostic efficacy of EGFR expression level.

Irreversible tyrosine kinase inhibitors induce the endocytosis and downregulation of ErbB2

Erb-b2 receptor tyrosine kinase 2 (ErbB2) is an oncogene that frequently overexpressed in a subset of cancers. Anti-ErbB2 therapies have been developed to treat these types of cancers. However, less is known about how anti-ErbB2 drugs affect the trafficking and degradation of ErbB2. We demonstrate that the reversible and irreversible tyrosine kinase inhibitors (TKIs) differentially modulate the subcellular trafficking and downregulation of ErbB2. Only the irreversible TKIs can induce the loss of ErbB2 expression, which is not dependent on proteasome or lysosome. The irreversible TKIs promote ErbB2 endocytosis from plasma membrane and enhance the ErbB2 accumulation at endosomes. The endocytosis of ErbB2 is mediated by a dynamin-dependent but clathrin-independent mechanism. Blocking of ErbB2 endocytosis can impair the TKI-induced ErbB2 downregulation.

Improving Radiotherapy Response in the Treatment of Head and Neck Cancer

The application of radiotherapy to the treatment of cancer has existed for over 100 years. Although its use has cured many, much work remains to be done to minimize side effects, and in-field tumor recurrences. Resistance of the tumor to a radiation-mediated death remains a complex issue that results in local recurrence and significantly decreases patient survival. Here, we review mechanisms of radioresistance and selective treatment combinations that improve the efficacy of the radiation that is delivered. Further investigation into the underlying mechanisms of radiation resistance is warranted to develop not just novel treatments, but treatments with improved safety profiles relative to current radiosensitizers. This review is written in memory and honor of Dr. Peter Stambrook, an avid scientist and thought leader in the field of DNA damage and carcinogenesis, and a mentor and advocate for countless students and faculty.

Rapid and Quantitative Intraoperative Pathology-Assisted Surgery by Paired-Agent Imaging-Derived Confidence Map

PURPOSE

In nonmetastatic head and neck cancer treatment, surgical margin status is the most important prognosticator of recurrence and patient survival. Fresh frozen sectioning (FFS) of tissue margins is the standard of care for intraoperative margin assessment. However, FFS is time intensive, and its accuracy is not consistent among institutes. Mapping the epidermal growth factor receptor (EGFR) using paired-agent imaging (PAI) has the potential to provide more consistent intraoperative margin assessment in a fraction of the time as FFS.

PROCEDURES

PAI was carried out through IV injection of an anti-epidermal growth factor receptor (EGFR) affibody molecule (ABY-029, eIND 122,681) and an untargeted IRDye680LT carboxylate. Imaging was performed on 4 µm frozen sections from three oral squamous cell carcinoma xenograft mouse models (n = 24, 8 samples per cell line). The diagnostic ability and tumor contrast were compared between binding potential, targeted, and untargeted images. Confidence maps were constructed based on group histogram-derived tumor probability curves. Tumor differentiability and contrast by confidence maps were evaluated.

RESULTS

PAI outperformed ABY-029 and IRDye 680LT alone, demonstrating the highest individual receiver operating characteristic (ROC) curve area under the curve (PAI AUC: 0.91, 0.90, and 0.79) and contrast-to-noise ratio (PAI CNR: 1, 1.1, and 0.6) for FaDu, Det 562, and A253. PAI confidence maps (PAI CM) maintain high tumor diagnostic ability (PAI CMAUC: 0.91, 0.90, and 0.79) while significantly enhancing tumor contrast (PAI CMCNR: 1.5, 1.3, and 0.8) in FaDu, Det 562, and A253. Additionally, the PAI confidence map allows avascular A253 to be differentiated from a healthy tissue with significantly higher contrast than PAI. Notably, PAI does not require additional staining and therefore significantly reduces the tumor delineation time in a 5 [Formula: see text] 5 mm slice from ~ 35 min to under a minute.

CONCLUSION

This study demonstrated that PAI improved tumor detection in frozen sections with high diagnostic accuracy and rapid analysis times. The novel PAI confidence map improved the contrast in vascular tumors and differentiability in avascular tumors. With a larger database, the PAI confidence map promises to standardize fluorescence imaging in intraoperative pathology-assisted surgery (IPAS).

MEK Is a Potential Indirect Target in Subtypes of Head and Neck Cancers

The poor prognosis of head-and-neck squamous cell carcinoma (HNSCC) is partly due to the lack of reliable prognostic and predictive markers. The Ras/Raf/MEK/ERK signaling pathway is often activated by overexpressed epidermal growth factor receptor (EGFR) and stimulates the progression of HNSCCs. Our research was performed on three human papillomavirus (HPV)-negative HNSCC-cell lines: Detroit 562, FaDu and SCC25. Changes in cell viability upon EGFR and/or MEK inhibitors were measured by the MTT method. The protein-expression and phosphorylation profiles of the EGFR-initiated signaling pathways were assessed using Western-blot analysis. The EGFR expression and pY1068-EGFR levels were also studied in the patient-derived HNSCC samples. We found significant differences between the sensitivity of the tumor-cell lines used. The SCC25 line was found to be the most sensitive to the MEK inhibitors, possibly due to the lack of feedback Akt activation through EGFR. By contrast, this feedback activation had an important role in the FaDu cells. The observed insensitivity of the Detroit 562 cells to the MEK inhibitors might have been caused by their PIK3CA mutation. Among HNSCC cell lines, EGFR-initiated signaling pathways are particularly versatile. An ERK/EGFR feedback loop can lead to Akt-pathway activation upon MEK inhibition, and it is related not only to increased amounts of EGFR but also to the elevation of pY1068-EGFR levels. The presence of this mechanism may justify the combined application of EGFR and MEK inhibitors.

Novel Insights of Anti-EGFR Therapy in HNSCC: Combined with Immunotherapy or Not?

PURPOSE OF REVIEW

The efficacy of anti-EGFR therapy is still unfavorable in recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) patients. Disorder of antitumor immunity and aberrantly expressed checkpoint biomarkers had been validated to involve anti-EGFR therapy tolerance and efficacy. Here we review the immunomodulation of anti-EGFR therapy in the tumor immune microenvironment (TIME) of HNSCC and assist clinicians in finding the potential strategies to rescue anti-EGFR tolerance therapy in the era of immunotherapy for HNSCC.

RECENT FINDINGS

Anti-EGFR therapy, especially cetuximab, was validated to induce the innate and adaptive immune responses of HNSCC patients. It is mainly through inducing natural killer (NK) cells mediating antibody-dependent cell-mediated cytotoxicity (ADCC), recruiting multiple tumor-infiltrating immune cells, and finally remodeling the TIME. Moreover, mountains of preclinical models and clinical trials revealed that combining anti-EGFR agents with immunotherapy could enhance the antitumor effectiveness in HNSCC. Anti-EGFR therapy may usher in another dawn in the treatment of patients with HNSCC through combination with immunotherapy. We offer an overview of the ongoing efforts to make out the immunomodulation of the EGFR pathway in both innate and adaptive immune responses; update the constant preclinical models and clinical trials for the combination of anti-EGFR and immunotherapy in HNSCC; and finally evaluate the efficacy and advantages of the combination therapeutic strategies in clinical use.

Targeted therapy for head and neck cancer: signaling pathways and clinical studies

Head and neck cancer (HNC) is malignant, genetically complex and difficult to treat and is the sixth most frequent cancer, with tobacco, alcohol and human papillomavirus being major risk factors. Based on epigenetic data, HNC is remarkably heterogeneous, and treatment remains challenging. There is a lack of significant improvement in survival and quality of life in patients with HNC. Over half of HNC patients experience locoregional recurrence or distal metastasis despite the current multiple traditional therapeutic strategies and immunotherapy. In addition, resistance to chemotherapy, radiotherapy and some targeted therapies is common. Therefore, it is urgent to explore more effective and tolerable targeted therapies to improve the clinical outcomes of HNC patients. Recent targeted therapy studies have focused on identifying promising biomarkers and developing more effective targeted therapies. A well understanding of the pathogenesis of HNC contributes to learning more about its inner association, which provides novel insight into the development of small molecule inhibitors. In this review, we summarized the vital signaling pathways and discussed the current potential therapeutic targets against critical molecules in HNC, as well as presenting preclinical animal models and ongoing or completed clinical studies about targeted therapy, which may contribute to a more favorable prognosis of HNC. Targeted therapy in combination with other therapies and its limitations were also discussed.

Hypoxia-mediated activation of hypoxia-inducible factor-1α in head and neck squamous cell carcinoma: A review

Since the 1950s, hypoxia has been recognized as a crucial characteristic of cancer cells and their microenvironment. Indeed, hypoxia promotes the growth, survival, and metastasis of cancer cells. In the early 1990s, we found that as many phenomena in hypoxia can occur through hypoxia-inducible factor-1α (HIF1α). HIF1α is known as an angiogenesis converter in hypoxia, which promotes tumorigenesis, development, immune escape, recurrence, etc; This page goes into great detail on how HIF1α is activated during hypoxia and how the 2 signaling channels interact. It specifically emphasizes the significance of reactive oxygen species, the function of the PI3K/the serine/threonine kinase Akt/mammalian target of rapamycin cascade, and outlines the similarities between the 2 important factors (reactive oxygen species and PI3K/the serine/threonine kinase Akt/mammalian target of rapamycin cascade), nuclear factor κB, for HIF1α Important implications, in an effort to offer fresh views for the treatment of head and neck squamous cell carcinoma and HIF1α research.

Anti-EGFR-Based Therapy in Recurrent or Metastatic HNSCC - What Difference Does it Make?

Patients with R/M HNSCC treated with palliative first-line therapy at Hannover Medical School between October 2005 and December 2016 have been included to show changes in survival following broad utilization of cetuximab. Treatment periods were defined from 10/2005 to 12/2008 (Period A) and 01/2009 to 12/2016. Overall survival did not improve over time. However, in subgroup analysis cetuximab utilized at any time vs. never showed a significant improve of overall survival (11.3 vs. 6.3 months, HR: 0.55, 95%-CI: 0.4-0.8, p = 0.04). Therefore, this study supports the application of cetuximab in this real-world population.

Immunomodulatory Therapy in Head and Neck Squamous Cell Carcinoma: Recent Advances and Clinical Prospects

The immune system plays a significant role in the development, invasion, progression, and metastasis of head and neck cancer. Over the last decade, the emergence of immunotherapy has irreversibly altered the paradigm of cancer treatment. The current treatment modalities for head and neck squamous cell carcinoma (HNSCC) include surgery, radiotherapy, and adjuvant or neoadjuvant chemotherapy which has failed to provide satisfactory clinical outcomes. To encounter this, there is a need for a novel or targeted therapy such as immunological targets along with conventional treatment strategy for optimal therapeutic outcomes. The immune system can contribute to promoting metastasis, angiogenesis, and growth by exploiting the tumor's influence on the microenvironment. Immunological targets have been found effective in recent clinical studies and have shown promising results. This review outlines the important immunological targets and the medications acting on them that have already been explored, are currently under clinical trials and are further being targeted.

Novel Systemic Treatment Modalities Including Immunotherapy and Molecular Targeted Therapy for Recurrent and Metastatic Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinomas (HNSCCs) are the sixth most common cancers worldwide. More than half of patients with HNSCC eventually experience disease recurrence and/or metastasis, which can threaten their long-term survival. HNSCCs located in the oral cavity and larynx are usually associated with tobacco and/or alcohol use, whereas human papillomavirus (HPV) infection, particularly HPV16 infection, is increasingly recognized as a cause of oropharyngeal HNSCC. Despite clinical, histologic, and molecular differences between HPV-positive and HPV-negative HNSCCs, current treatment approaches are the same. For recurrent disease, these strategies include chemotherapy, immunotherapy with PD-1-inhibitors, or a monoclonal antibody, cetuximab, that targets epidermal growth factor; these therapies can be administered either as single agents or in combination. However, these treatment strategies carry a high risk of toxic side effects; therefore, more effective and less toxic treatments are needed. The landscape of HNSCC therapy is changing significantly; numerous clinical trials are underway to test novel therapeutic options like adaptive cellular therapy, antibody-drug conjugates, new targeted therapy agents, novel immunotherapy combinations, and therapeutic vaccines. This review helps in understanding the various developments in HNSCC therapy and sheds light on the path ahead in terms of further research in this field.

Receptor, Signal, Nucleus, Action: Signals That Pass through Akt on the Road to Head and Neck Cancer Cell Migration

Simple Summary

The ecosystem that surrounds a tumour, the microenvironment, has a huge impact on the spread of cancer, but its exact role in the molecular mechanism of spreading is still under scrutiny. This literature review aims to focus on the evidence published on the production of growth factors or proteins from the tumour microenvironment, which initiate signals in cancer cells. This review provides evidence that when Akt, a signalling protein, is activated by different growth factors such as epidermal growth factor, transforming growth factor α/β, vascular endothelial growth factor and nerve growth factor, head and neck cancer cell spreading is stimulated. In a nutshell, it demonstrates that the tumour microenvironment plays an important role in cancer spreading by synthesising and secreting growth factors and suggests that targeting growth-factor-activated Akt in combination therapy could be a valuable therapeutic approach in treating head and neck cancer patients.

Abstract

This review aims to provide evidence for the role of the tumour microenvironment in cancer progression, including invasion and metastasis. The tumour microenvironment is complex and consists of tumour cells and stromal-derived cells, in addition to a modified extracellular matrix. The cellular components synthesise growth factors such as EGF, TGFα and β, VEGF, and NGF, which have been shown to initiate paracrine signalling in head and neck cancer cells by binding to cell surface receptors. One example is the phosphorylation, and hence activation, of the signalling protein Akt, which can ultimately induce oral cancer cell migration in vitro. Blocking of Akt activation by an inhibitor, MK2206, leads to a significant decrease, in vitro, of cancer-derived cell migration, visualised in both wound healing and scatter assays. Signalling pathways have therefore been popular targets for the design of chemotherapeutic agents, but drug resistance has been observed and is related to direct tumour–tumour cell communication, the tumour–extracellular matrix interface, and tumour–stromal cell interactions. Translation of this knowledge to patient care is reliant upon a comprehensive understanding of the complex relationships present in the tumour microenvironment and could ultimately lead to the design of efficacious treatment regimens such as targeted therapy or novel therapeutic combinations.

Precision Medicine in Head and Neck Cancers: Genomic and Preclinical Approaches

Head and neck cancers (HNCs) represent the sixth most widespread malignancy worldwide. Surgery, radiotherapy, chemotherapeutic and immunotherapeutic drugs represent the main clinical approaches for HNC patients. Moreover, HNCs are characterised by an elevated mutational load; however, specific genetic mutations or biomarkers have not yet been found. In this scenario, personalised medicine is showing its efficacy. To study the reliability and the effects of personalised treatments, preclinical research can take advantage of next-generation sequencing and innovative technologies that have been developed to obtain genomic and multi-omic profiles to drive personalised treatments. The crosstalk between malignant and healthy components, as well as interactions with extracellular matrices, are important features which are responsible for treatment failure. Preclinical research has constantly implemented in vitro and in vivo models to mimic the natural tumour microenvironment. Among them, 3D systems have been developed to reproduce the tumour mass architecture, such as biomimetic scaffolds and organoids. In addition, in vivo models have been changed over the last decades to overcome problems such as animal management complexity and time-consuming experiments. In this review, we will explore the new approaches aimed to improve preclinical tools to study and apply precision medicine as a therapeutic option for patients affected by HNCs.

Tubeimoside-I sensitizes temozolomide-resistant glioblastoma cells to chemotherapy by reducing MGMT expression and suppressing EGFR induced PI3K/Akt/mTOR/NF-κB-mediated signaling pathway

BACKGROUND

Glioblastoma multiforme (GBM, World Health Organization [WHO] grade IV) is one of the malignant Central Nerve System (CNS) tumors with high incidence rate and poor prognosis. The use of alkylating agents, such as temozolomide (TMZ), has been the main method of cytotoxic therapy for glioma patients for decades. However, TMZ resistance may be one of the major reasons for treatment failure, so far. In searching for effective agents to reverse TMZ resistance, we found that Tubeimoside-I (TBMS1), a saponin from traditional Chinese medicine, Bolbostemma paniculatum (Maxim.) Franquet, showed activities of reversing TMZ resistance of GBM. However, the ability of TBMS1 enhancing the chemosensitivity of GBM has been rarely studied, and its underlying mechanisms remain unclear.

PURPOSE

This study purposes to reveal the synergistic effects and mechanism of TBMS1 and TMZ against TMZ-resistant GBM cells.

METHODS

CCK8 assay was used to investigate the anti-proliferative effects on grade IV glioblastoma human T98G and U118 MG cells. Cell proliferation was determined by EdU assay and clonogenic assay after TMZ plus TBMS1 treatment. Apoptosis was analyzed by flow cytometry. DNA damage and DNA Double Strand Break (DSB) were assessed by cleaved Poly (ADP-ribose) polymerase (PARP), γH2AX Foci Assay and Comet Assay, respectively. Expression of proteins associated with apoptosis and DNA repair enzymes were measured by Western blot analysis. The prognostic significance of key proteins of the epidermal growth factor receptor (EGFR) induced PI3K/Akt/mTOR/NF-κB signaling pathway was analyzed using GEPIA (http://gepia.cancer-pku.cn) and validated by Western blotting.

RESULTS

Here we demonstrated that TBMS1 sensitized TMZ-resistant T98G and U118 MG glioblastoma cells to chemotherapy and exhibited promotion of apoptosis and inhibition on cell viability, proliferation and clone formation. Coefficient of drug in interaction (CDI) values showed a notable synergistic effect between TBMS1 and TMZ. Moreover, we observed that combination of TBMS1 and TMZ induced apoptosis was accompanied by robust DSB, γH2AX Foci formation and increasing cleaved PARP, as well as the heightened ratio of Bax/Bcl-2, cleavages of caspase-3 and caspase-9. In addition, the synergistic anti-glioma effect between TBMS1 and TMZ was intimately related to the reduction of MGMT expression in TMZ-resistant GBM cells. Moreover, it was also associated with attenuated expression of EGFR, p-PI3K-p85, p-Akt (Ser473), p-mTOR (Ser2481) and p-NF-κB p65(Ser536), which implying deactivation of the EGFR induced PI3K/Akt/mTOR/NF-κB signaling pathway.

CONCLUSION

We first demonstrated that synergistic effects of TBMS1 and TMZ induced apoptosis in GBM cells through reducing MGMT expression and inhibiting the EGFR induced PI3K/Akt/mTOR/NF-κB signaling pathway. This study provides a rationale for combined application of TMZ and TBMS1 as a potential chemotherapeutic treatment for MGMT+ GBM patients.

Analysis of the epidermal growth factor receptor/phosphoinositide‐dependent protein kinase‐1 axis in tumor of the external auditory canal in response to epidermal growth factor stimulation

Objectives

The epidermal growth factor receptor (EGFR) is related to the invasion and metastasis of external auditory canal (EAC) squamous cell carcinoma (SCC). The phosphoinositide‐dependent protein kinase‐1 (PDPK1) accelerates tumor cell growth through anti‐apoptotic signaling under the influence of downstream EGFR‐mediated signaling pathways. In this study, we investigated the EGFR/PDPK1 axis in the EAC under EGF stimulation.

Methods

We confirmed EGFR and PDPK1 expression in human EACSCC specimens immunohistochemically. We next transfected the EGF expression vector in the mouse EAC and then conducted a PDPK1 inhibitory experiment. Immunohistochemical analysis was performed in the mouse EAC, using anti‐EGF, anti‐EGFR, anti‐PDPK1, and anti‐Ki67 antibodies. Immunohistochemical analysis of cleaved caspase‐3 and terminal deoxy(d)‐UTP nick end labeling (TUNEL) detection assays were also performed for the assessment of apoptosis in the inhibitory experiment.

Results

Immunohistochemical analysis revealed overexpression and colocalization of EGFR and PDPK1 in human EACSCC specimens. The growth of a protuberant tumor was observed in the mouse EAC in which EGF expression vector was transfected, and EGF, EGFR, PDPK1, and Ki67 labeling indexes (LIs) were significantly increased. PDPK1 inhibition then induced normal epithelial appearance in the EAC. Moreover, EGF, EGFR, PDPK1, and Ki67 LIs were decreased, and cleaved caspase‐3 and TUNEL LIs were increased in the EAC.

Conclusion

We demonstrated the possibility that PDPK1 plays an important role in EACSCC.

Level of Evidence: NA.

EGFR Mutations in Head and Neck Squamous Cell Carcinoma

EGFR is a prototypical receptor tyrosine kinase that is overexpressed in multiple cancers including head and neck squamous cell carcinoma (HNSCC). The standard of care for HNSCC remains largely unchanged despite decades of research. While EGFR blockade is an attractive target in HNSCC patients and anti-EGFR strategies including monoclonal antibodies and kinase inhibitors have shown some clinical benefit, efficacy is often due to the eventual development of resistance. In this review, we discuss how the acquisition of mutations in various domains of the EGFR gene not only alter drug binding dynamics giving rise to resistance, but also how mutations can impact radiation response and overall survival in HNSCC patients. A better understanding of the EGFR mutational landscape and its dynamic effects on treatment resistance hold the potential to better stratify patients for targeted therapies in order to maximize therapeutic benefits.

Possible Action of Olaparib for Preventing Invasion of Oral Squamous Cell Carcinoma In Vitro and In Vivo

Despite recent advances in treatment, the prognosis of oral cancer remains poor, and prevention of recurrence and metastasis is critical. Olaparib is a PARP1 inhibitor that blocks polyADP-ribosylation, which is involved in the epithelial–mesenchymal transition (EMT) characteristic of tumor recurrence. We explored the potential of olaparib in inhibiting cancer invasion in oral carcinoma using three oral cancer cell lines, HSC-2, Ca9-22, and SAS. Olaparib treatment markedly reduced their proliferation, migration, invasion, and adhesion. Furthermore, qRT-PCR revealed that olaparib inhibited the mRNA expression of markers associated with tumorigenesis and EMT, notably Ki67, Vimentin, β-catenin, MMP2, MMP9, p53, and integrin α2 and β1, while E-Cadherin was upregulated. In vivo analysis of tumor xenografts generated by injection of HSC-2 cells into the masseter muscles of mice demonstrated significant inhibition of tumorigenesis and bone invasion by olaparib compared with the control. This was associated with reduced expression of proteins involved in osteoclastogenesis, RANK and RANKL. Moreover, SNAIL and PARP1 were downregulated, while E-cadherin was increased, indicating the effect of olaparib on proteins associated with EMT in this model. Taken together, these findings confirm the effects of olaparib on EMT and bone invasion in oral carcinoma and suggest a new therapeutic strategy for this disease.

Alcohol and Head and Neck Cancer: Updates on the Role of Oxidative Stress, Genetic, Epigenetics, Oral Microbiota, Antioxidants, and Alkylating Agents

Head and neck cancer (HNC) concerns more than 890,000 patients worldwide annually and is associated with the advanced stage at presentation and heavy outcomes. Alcohol drinking, together with tobacco smoking, and human papillomavirus infection are the main recognized risk factors. The tumorigenesis of HNC represents an intricate sequential process that implicates a gradual acquisition of genetic and epigenetics alterations targeting crucial pathways regulating cell growth, motility, and stromal interactions. Tumor microenvironment and growth factors also play a major role in HNC. Alcohol toxicity is caused both directly by ethanol and indirectly by its metabolic products, with the involvement of the oral microbiota and oxidative stress; alcohol might enhance the exposure of epithelial cells to carcinogens, causing epigenetic modifications, DNA damage, and inaccurate DNA repair with the formation of DNA adducts. Long-term markers of alcohol consumption, especially those detected in the hair, may provide crucial information on the real alcohol drinking of HNC patients. Strategies for prevention could include food supplements as polyphenols, and alkylating drugs as therapy that play a key role in HNC management. Indeed, polyphenols throughout their antioxidant and anti-inflammatory actions may counteract or limit the toxic effect of alcohol whereas alkylating agents inhibiting cancer cells’ growth could reduce the carcinogenic damage induced by alcohol. Despite the established association between alcohol and HNC, a concerning pattern of alcohol consumption in survivors of HNC has been shown. It is of primary importance to increase the awareness of cancer risks associated with alcohol consumption, both in oncologic patients and the general population, to provide advice for reducing HNC prevalence and complications.

Prevalence of HPV in Mexican Patients with Head and Neck Squamous Carcinoma and Identification of Potential Prognostic Biomarkers

Simple Summary

Head and neck squamous cell carcinomas (HNSCC) are a heterogeneous group of neoplasms that show diverse clinical and biological characteristics associated with human papillomavirus (HPV). Biological and clinical characterization is essential to stratify patients based on prognostic and predictive factors. The biological features of HNSCC may change according to geography and population characteristics. Studies on the molecular biology of HNSCC in Mexico are scarce. In the present study, we analyzed 414 Mexican patients with HNSCC and determined the presence and genotype of HPV, p16 expression, and global gene expression profiles. Twenty-two percent of total cases were HPV+, and 32% were p16+. We identified genes associated with survival, such as SLIRP, KLF10, AREG, ACT1, and LIMA. In addition, CSF1R, MYC, and SRC genes were identified as potential therapeutic targets. This study offers information that may be relevant for our understanding of the biology of HNSCC and the development of therapeutic strategies.

Abstract

Head and neck squamous cell carcinomas (HNSCC) show a variety of biological and clinical characteristics that could depend on the association with the human papillomavirus (HPV). Biological and clinical characterization is essential to stratify patients based on prognostic and predictive factors. Reports on HNSCC are scarce in Mexico. Herein, we analyzed 414 Mexican patients with HNSCC, including oropharynx (OPSCC), larynx (LASCC), and oral cavity (OCSCC), and identified HPV DNA and p16 expression. Global gene expression profiles were analyzed in 25 HPV+/p16+ vs. HPV−/p16− cases. We found 32.3% p16+ and 22.3% HPV+ samples, HPV 16, 18, 39, 52, and 31 being the most frequent genotypes. For OPSCC, LASCC and OCSCC, 39.2, 14.7, and 9.6% were HPV+/p16+, respectively. High expression of SLIRP, KLF10, AREG, and LIMA was associated with poor survival; in contrast, high expression of MYB and SYCP2 correlated with better survival. In HPV+ cases, high expression of SLC25A39 and GJB2 was associated with poor survival. Likewise, EGFR, IL-1, IL-6, JAK-STAT, WNT, NOTCH, and ESR1 signaling pathways were downregulated in HPV+ cases. CSF1R, MYC, and SRC genes were identified as key hubs and therapeutic targets. Our study offers information regarding the molecular and clinical characteristics of HNSCC in Mexican patients.

Exploring the Application of Bifunctional Metal Chelators in Treating Triple-Negative Breast Cancer

Purpose: In this study, we independently synthesised and labelled a novel bidentate bifunctional chelating agent, ¹⁷⁷Lu-3,4-HOPO-Cetuximab, that achieved tight binding between targeting and radioactivity, and evaluated its targeted killing ability of cells in vitro and in vivo. Method: 3,4-HOPO was successfully synthesised through a series of chemical steps using malt phenol as the raw material, which was then coupled with Cetuximab labelled with ¹⁷⁷Lu. ¹⁷⁷Lu-3,4-HOPO-Cetuximab and ¹⁷⁷Lu-DOTA-Cetuximab was tested for its cell viability and cell-binding rate after different times and at different doses by CCK-8 and cell-binding experiments. ¹⁷⁷Lu-3,4-HOPO-Cetuximab (~500 μCi) and ¹⁷⁷Lu-DOTA-Cetuximab (~500 μCi) were injected into the tail vein of a subcutaneous metastasis mouse model of triple-negative breast cancer with a single injection, and tumour volume growth and body weight changes were regularly monitored for 20 days. The radioactivity distribution in nude mice was analysed after sacrifice, and the treated and untreated tumour tissues were analysed by HE staining. Result: The cell viability of ¹⁷⁷Lu-3,4-HOPO-Cetuximab declined exponentially after treatment for 48 h at 50 Bq/mL to 500 kBq/mL, respectively; the cell activity was slowed down from 8 to 96 h at a dose of 500 kBq; while the binding rate of 4T1 cells in ¹⁷⁷Lu-3,4-HOPO-Cetuximab from 1 to 24 h, respectively, increased logarithmically, which was similar with ¹⁷⁷Lu-DOTA-Cetuximab. After 20 days of treatment, the body weight of nude mice with ¹⁷⁷Lu-3,4-HOPO-Cetuximab and ¹⁷⁷Lu-DOTA-Cetuximab were hardly changed, while the body weight with physiological saline decreased significantly. The tumour inhibition rate of the ¹⁷⁷Lu-3,4-HOPO-Cetuximab and ¹⁷⁷Lu-DOTA-Cetuximab were (37.03 ± 11.16)% and (38.7 ± 5.1)%; HE staining showed that tumour cells were affected by the action of ¹⁷⁷Lu causing necrosis. Conclusion: The experiments showed that ¹⁷⁷Lu-3,4-HOPO-Cetuximab has a certain targeted therapeutic ability for triple-negative breast cancer, and it is expected to become a potential targeted nuclear medicine treatment for triple-negative breast cancer.

Translational Insights and New Therapeutic Perspectives in Head and Neck Tumors

Head and neck squamous cell carcinoma (HNSCC) is characterized by a high mortality rate owing to very few available oncological treatments. For many years, a combination of platinum-based chemotherapy and anti-EGFR antibody cetuximab has represented the only available option for first-line therapy. Recently, immunotherapy has been presented an alternative for positive PD-L1 HNSCC. However, the oncologists' community foresees that a new therapeutic era is approaching. In fact, no-chemo options and some molecular targets are on the horizon. This narrative review addresses past, present, and future therapeutic options for HNSCC from a translational point of view.

The Application of Inorganic Nanoparticles in Molecular Targeted Cancer Therapy: EGFR Targeting

Epidermal growth factor receptor (EGFR) is an anticancer drug target for a number of cancers, such as non-small cell lung cancer. However, unsatisfying treatment effects, terrible side-effects, and development of drug resistance are current insurmountable challenges of EGFR targeting treatments for cancers. With the advancement of nanotechnology, an increasing number of inorganic nanomaterials are applied in EGFR-mediated therapy to improve those limitations and further potentiate the efficacy of molecular targeted cancer therapy. Given their facile preparation, easy modification, and biosecurity, inorganic nanoparticles (iNPs) have been extensively explored in cancer treatments to date. This review presents an overview of the application of some typical metal nanoparticles and nonmetallic nanoparticles in EGFR-targeted therapy, then discusses and summarizes the relevant advantages. Moreover, we also highlight future perspectives regarding their remaining issues. We hope these discussions inspire future research on EGFR-targeted iNPs.

Immune deserts in head and neck squamous cell carcinoma: A review of challenges and opportunities for modulating the tumor immune microenvironment

Immunotherapy revolutionized cancer treatment but has yet to elicit durable responses in the majority of patients with head and neck squamous cell carcinoma (HNSCC). HNSCC is generally characterized by a high tumor mutational burden, which has translated to a large neoantigen load that could prime the immune system to recognize and eliminate malignant cells. Studies are increasingly showing, however, that HNSCC is an "immune desert" tumor that can hijack multiple parts of the tumor immunity cycle in order to evade immune recognition and suppress immune system activation. Herein we will review how HNSCC tumors modulate their architecture, cellular composition, and cytokine milieu to maximize immunosuppression; as well as relevant therapeutic opportunities and emerging issues facing the field of HNSCC immuno-oncology.