Cetuximab-induced natural killer cell cytotoxicity in head and neck squamous cell carcinoma cell lines: investigation of the role of cetuximab sensitivity and HPV status

NK cell based immunotherapy against oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC), a major subtype of head and neck cancers, presents significant challenges due to its aggressive feature and limited therapeutic efficacy of conventional treatments. In response to these challenges, Natural Killer (NK) cells, a vital component of the innate immune system, are being explored for their therapeutic potential in OSCC due to their inherent ability to target and eliminate cancer cells without prior sensitization. This review uniquely focuses on the evolving role of NK cells specifically in OSCC, incorporating recent advancements in CAR-NK cell engineering and personalized therapy approaches that have not been comprehensively covered in previous reviews. The mechanisms through which NK cells exert cytotoxic effects on tumor cells include direct killing through the engagement of natural cytotoxic receptors and antibody-dependent cellular cytotoxicity (ADCC), making them promising agents in cancer immunotherapy. Additionally, the article explores recent advancements in engineering NK cells to enhance their antitumor activity, such as the modification with chimeric antigen receptors (CARs) to target specific tumor antigens. Clinical implications of NK cell-based therapies, including the challenges of integrating these treatments with existing protocols and the potential for personalized therapy, are examined. The review highlights the promise of NK cell therapies in improving outcomes for OSCC patients and outlines future directions for research in this dynamic field of oncological immunotherapy.

HPV-associated oropharyngeal carcinomas in patients living with HIV on long-term antiretroviral therapy: Case reports

In the 1970s, human papillomaviruses (HPV) were ascertained as the aetiologic agents of cervical carcinoma. Subsequently, an association with HPV was established in other epithelial tumours, including squamous cell carcinoma of the head and neck (HNSCC). HPV has demonstrated a high potential for inducing oropharyngeal tumours, with HPV-16 infection posing a significant oncogenic risk. People living with HIV (PLWH) are identified as being at a higher risk of HPV infection and the subsequent development of HPV-associated tumours of the oropharynx. We present two patients under the care of the Department of AIDS with long-term HIV infections who were newly diagnosed with HPV-associated carcinomas of the tonsils. Both patients had been on antiretroviral therapy (ART) for over 15 years, achieving optimal viral suppression for more than 10 years. Chemotherapy and radiation therapy were employed in the treatment of the carcinomas. Throughout the neoplastic disease treatment, both patients maintained optimal viral suppression for HIV. The presented cases underscore the fact that despite achieving long-term optimal viral suppression of HIV, people living with HIV remain susceptible to the development of HPV-associated neoplasms.

CHMP2A regulates broad immune cell-mediated antitumor activity in an immunocompetent in vivo head and neck squamous cell carcinoma model

BACKGROUND

Natural killer (NK) cells are key effector cells of antitumor immunity. However, tumors can acquire resistance programs to escape NK cell-mediated immunosurveillance. Identifying mechanisms that mediate this resistance enables us to define approaches to improve immune-mediate antitumor activity. In previous studies from our group, a genome-wide CRISPR-Cas9 screen identified Charged Multivesicular Body Protein 2A (CHMP2A) as a novel mechanism that mediates tumor intrinsic resistance to NK cell activity.

METHODS

Here, we use an immunocompetent mouse model to demonstrate that CHMP2A serves as a targetable regulator of not only NK cell-mediated immunity but also other immune cell populations. Using the recently characterized murine 4MOSC model system, a syngeneic, tobacco-signature murine head and neck squamous cell carcinoma model, we deleted mCHMP2A using CRISPR/Cas9-mediated knock-out (KO), following orthotopic transplantation into immunocompetent hosts.

RESULTS

We found that mCHMP2A KO in 4MOSC1 cells leads to more potent NK-mediated tumor cell killing in vitro in these tumor cells. Moreover, following orthotopic transplantation, KO of mCHMP2A in 4MOSC1 cells, but not the more immune-resistant 4MOSC2 cells enables both T cells and NK cells to better mediate antitumor activity compared with wild type (WT) tumors. However, there was no difference in tumor development between WT and mCHMP2A KO 4MOSC1 or 4MOSC2 tumors when implanted in immunodeficient mice. Mechanistically, we find that mCHMP2A KO 4MOSC1 tumors transplanted into the immunocompetent mice had significantly increased CD4+T cells, CD8+T cells. NK cell, as well as fewer myeloid-derived suppressor cells (MDSC).

CONCLUSIONS

Together, these studies demonstrate that CHMP2A is a targetable inhibitor of cellular antitumor immunity.

Safety and efficacy of SNK01 (autologous natural killer cells) in combination with cytotoxic chemotherapy and/or cetuximab after failure of prior tyrosine kinase inhibitor in non-small cell lung cancer: non-clinical mouse model and phase I/IIa clinical study

BACKGROUND

Choosing treatments for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients with osimertinib resistance is challenging. We evaluated the safety and efficacy of SNK01 (autologous natural killer (NK) cells) in combination with cytotoxic chemotherapy and/or cetuximab (an anti-EGFR monoclonal antibody) in treating EGFR-mutated NSCLC in this non-clinical and phase I/IIa clinical trial.

METHODS

We developed a cell line-derived xenograft-humanized mouse model with an osimertinib-resistant lung cancer cell line. The mice were divided into four groups based on treatment (no treatment, cetuximab, SNK01, and combination groups) and treated weekly for 5 weeks. In the clinical study, 12 patients with EGFR-mutated NSCLC who failed prior tyrosine kinase inhibitor (TKI) received SNK01 weekly in combination with gemcitabine/carboplatin (n=6) or cetuximab/gemcitabine/carboplatin (n=6) and dose escalation of SNK01 following the "3+3" design.

RESULTS

In the non-clinical study, an increase in NK cells in the blood and enhanced NK cell tumor infiltration were observed in the SNK01 group. The volume of tumor extracted after treatment was the smallest in the combination group. In the clinical study, 12 patients (median age, 60.9 years; all adenocarcinoma cases) received SNK01 weekly for 7-8 weeks (4×109 cells/dose (n=6); 6×109 cells/dose (n=6)). The maximum feasible dose of SNK01 was 6×109 cells/dose without dose-limiting toxicity. Efficacy outcomes showed an objective response rate of 25%, disease control rate of 100%, and median progression-free survival of 143 days.

CONCLUSION

SNK01 in combination with cytotoxic chemotherapy, including cetuximab, for EGFR-mutated NSCLC with TKI resistance was safe and exerted a potential antitumor effect.

TRIAL REGISTRATION NUMBER

NCT04872634.

Dual Checkpoint Aptamer Immunotherapy: Unveiling Tailored Cancer Treatment Targeting CTLA-4 and NKG2A

Recent strides in immunotherapy have illuminated the crucial role of CTLA-4 and PD-1/PD-L1 pathways in contemporary oncology, presenting both promises and challenges in response rates and adverse effects. This study employs a computational biology tool (in silico approach) to craft aptamers capable of binding to dual receptors, namely, inhibitory CTLA4 and NKG2A, thereby unleashing both T and NK cells and enhancing CD8+ T and NK cell functions for tumor cell lysis. Computational analysis highlighted AYA22T-R2-13 with HADDOCK scores of -78.2 ± 10.2 (with CTLA4), -60.0 ± 4.2 (with NKG2A), and -77.5 ± 5.6 (with CD94/NKG2A). Confirmation of aptamer binding to targeted proteins was attained via ELISA and flow cytometry methods. In vitro biological functionality was assessed using lactate dehydrogenase (LDH) cytotoxicity assay. Direct and competitive assays using ELISA and flow cytometry demonstrated the selective binding of AYA22T-R2-13 to CTLA4 and NKG2A proteins, as well as to the cell surface receptors of IL-2-stimulated T cells and NK cells. This binding was inhibited in the presence of competition from CTLA4 or NKG2A proteins. Remarkably, the blockade of CTLA4 or NKG2A by AYA22T-R2-13 augmented human CD8 T cell- and NK cell-mediated tumor cell lysis in vitro. Our findings highlight the precise binding specificity of AYA22T-R2-13 for CTLA4-B7-1/B7-2 (CD80/CD86) or CD94/NKG2A-HLA-E interactions, positioning it as a valuable tool for immune checkpoint blockade aptamer research in murine tumor models. These in vitro studies establish a promising foundation for further enhancing binding capacity and establishing efficacy and safety in animal models. Consequently, our results underscore the potential of AYA22T-R2-13 in cancer immunotherapy, offering high specificity, low toxicity, and the potential for cost-effective production.

IL-15-secreting CAR natural killer cells directed toward the pan-cancer target CD70 eliminate both cancer cells and cancer-associated fibroblasts

BACKGROUND

It remains challenging to obtain positive outcomes with chimeric antigen receptor (CAR)-engineered cell therapies in solid malignancies, like colorectal cancer (CRC) and pancreatic ductal adenocarcinoma (PDAC). A major obstacle is the lack of targetable surface antigens that are not shared by healthy tissues. CD70 emerges as interesting target, due to its stringent expression pattern in healthy tissue and its apparent role in tumor progression in a considerable amount of malignancies. Moreover, CD70 is also expressed on cancer-associated fibroblasts (CAFs), another roadblock for treatment efficacy in CRC and PDAC. We explored the therapeutic potential of CD70 as target for CAR natural killer (NK) cell therapy in CRC, PDAC, focusing on tumor cells and CAFs, and lymphoma.

METHODS

RNA-seq data and immunohistochemical analysis of patient samples were used to explore CD70 expression in CRC and PDAC patients. In addition, CD70-targeting CAR NK cells were developed to assess cytotoxic activity against CD70+ tumor cells and CAFs, and the effect of cytokine stimulation on their efficacy was evaluated. The in vitro functionality of CD70-CAR NK cells was investigated against a panel of tumor and CAF cell lines with varying CD70 expression. Lymphoma-bearing mice were used to validate in vivo potency of CD70-CAR NK cells. Lastly, to consider patient variability, CD70-CAR NK cells were tested on patient-derived organoids containing CAFs.

RESULTS

In this study, we identified CD70 as a target for tumor cells and CAFs in CRC and PDAC patients. Functional evaluation of CD70-directed CAR NK cells indicated that IL-15 stimulation is essential to obtain effective elimination of CD70+ tumor cells and CAFs, and to improve tumor burden and survival of mice bearing CD70+ tumors. Mechanistically, IL-15 stimulation resulted in improved potency of CD70-CAR NK cells by upregulating CAR expression and increasing secretion of pro-inflammatory cytokines, in a mainly autocrine or intracellular manner.

CONCLUSIONS

We disclose CD70 as an attractive target both in hematological and solid tumors. IL-15 armored CAR NK cells act as potent effectors to eliminate these CD70+ cells. They can target both tumor cells and CAFs in patients with CRC and PDAC, and potentially other desmoplastic solid tumors.

Multi-kinase compensation rescues EGFR knockout in a cell line model of head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is a debilitating disease with poor survival rates. While the epidermal growth factor receptor (EGFR)-targeting antibody Cetuximab is approved for treatment, responses are limited and the molecular mechanisms driving resistance remain incompletely understood.

METHODS

To better understand how cells survive without EGFR activity, we developed an EGFR knockout derivative of the UM-SCC-92 cell line using CRISPR/Cas9 technology. We then characterized changes to the transcriptome with RNAseq and changes in response to kinase inhibitors with resazurin cell viability assays. Finally, we tested if inhibitors with activity in the EGFR knockout model also had synergistic activity in combination with EGFR inhibitors in either wild type UM-SCC-92 cells or a known Cetuximab-resistant model.

RESULTS

Functional and molecular analysis showed that knockout cells had decreased cell proliferation, upregulation of FGFR1 expression, and an enhanced mesenchymal phenotype. In fact, expression of common EMT genes including VIM, SNAIL1, ZEB1 and TWIST1 were all upregulated in the EGFR knockout. Surprisingly, EGFR knockout cells were resistant to FGFR inhibitor monotherapies, but sensitive to combinations of FGFR and either XIAP or IGF-1R inhibitors. Accordingly, both wild type UM-SCC-92 and Cetuximab-resistant UM-SCC-104 cells with were sensitive to combined inhibition of EGFR, FGFR and either XIAP or IGF-1R.

CONCLUSIONS

These data offer insights into EGFR inhibitor resistance and show that resistance to EGFR knockout likely occurs through a complex network of kinases. Future studies of cetuximab-resistant HNSCC tumors are warranted to determine if this EMT phenotype and/or multi-kinase resistance is observed in patients.

Establishment of head and neck squamous cell carcinoma mouse models for cetuximab resistance and sensitivity

Aim: Acquired resistance to the targeted agent cetuximab poses a significant challenge in finding effective anti-cancer treatments for head and neck squamous cell carcinoma (HNSCC). To accurately study novel combination treatments, suitable preclinical mouse models for cetuximab resistance are key yet currently limited. This study aimed to optimize an acquired cetuximab-resistant mouse model, with preservation of the innate immunity, ensuring intact antibody-dependent cellular cytotoxicity (ADCC) functionality. Methods: Cetuximab-sensitive and acquired-resistant HNSCC cell lines, generated in vitro, were subcutaneously engrafted in Rag2 knock-out (KO), BALB/c Nude and CB17 Scid mice with/without Matrigel or Geltrex. Once tumor growth was established, mice were intraperitoneally injected twice a week with cetuximab for a maximum of 3 weeks. In addition, immunohistochemistry was used to evaluate the tumor and its microenvironment. Results: Despite several adjustments in cell number, cell lines and the addition of Matrigel, Rag2 KO and BALB/C Nude mice proved to be unsuitable for xenografting our HNSCC cell lines. Durable tumor growth of resistant SC263-R cells could be induced in CB17 Scid mice. However, these cells had lost their resistance phenotype in vivo. Immunohistochemistry revealed a high infiltration of macrophages in cetuximab-treated SC263-R tumors. FaDu-S and FaDu-R cells successfully engrafted into CB17 Scid mice and maintained their sensitivity/resistance to cetuximab. Conclusion: We have established in vivo HNSCC mouse models with intact ADCC functionality for cetuximab resistance and sensitivity using the FaDu-R and FaDu-S cell lines, respectively. These models serve as valuable tools for investigating cetuximab resistance mechanisms and exploring novel drug combination strategies.

Drug Repurposing to Circumvent Immune Checkpoint Inhibitor Resistance in Cancer Immunotherapy

Immune checkpoint inhibitors (ICI) have achieved unprecedented clinical success in cancer treatment. However, drug resistance to ICI therapy is a major hurdle that prevents cancer patients from responding to the treatment or having durable disease control. Drug repurposing refers to the application of clinically approved drugs, with characterized pharmacological properties and known adverse effect profiles, to new indications. It has also emerged as a promising strategy to overcome drug resistance. In this review, we summarized the latest research about drug repurposing to overcome ICI resistance. Repurposed drugs work by either exerting immunostimulatory activities or abolishing the immunosuppressive tumor microenvironment (TME). Compared to the de novo drug design strategy, they provide novel and affordable treatment options to enhance cancer immunotherapy that can be readily evaluated in the clinic. Biomarkers are exploited to identify the right patient population to benefit from the repurposed drugs and drug combinations. Phenotypic screening of chemical libraries has been conducted to search for T-cell-modifying drugs. Genomics and integrated bioinformatics analysis, artificial intelligence, machine and deep learning approaches are employed to identify novel modulators of the immunosuppressive TME.

Nanotechnology boosts the efficiency of tumor diagnosis and therapy

The incidence and mortality of cancer are gradually increasing. The highly invasive and metastasis of tumor cells increase the difficulty of diagnosis and treatment, so people pay more and more attention to the diagnosis and treatment of cancer. Conventional treatment methods, including surgery, radiotherapy and chemotherapy, are difficult to eliminate tumor cells completely. And the emergence of nanotechnology has boosted the efficiency of tumor diagnosis and therapy. Herein, the research progress of nanotechnology used for tumor diagnosis and treatment is reviewed, and the emerging detection technology and the application of nanodrugs in clinic are summarized and prospected. The first part refers to the application of different nanomaterials for imaging in vivo and detection in vitro, which includes magnetic resonance imaging, fluorescence imaging, photoacoustic imaging and biomarker detection. The distinctive physical and chemical advantages of nanomaterials can improve the detection sensitivity and accuracy to achieve tumor detection in early stage. The second part is about the nanodrug used in clinic for tumor treatment. Nanomaterials have been widely used as drug carriers, including the albumin paclitaxel, liposome drugs, mRNA-LNP, protein nanocages, micelles, membrane nanocomplexes, microspheres et al., which could improve the drug accumulate in tumor tissue through enhanced permeability and retention effect to kill tumor cells with high efficiency. But there are still some challenges to revolutionize traditional tumor diagnosis and anti-drug resistance based on nanotechnology.

The Histological Background of Recurrence in Laryngeal Squamous Cell Carcinoma: An Insight into the Modifications of Tumor Microenvironment

Recurrent laryngeal carcinoma presents differences from the primary tumor that largely depend on the treatment. In this article, we review the histologic and molecular treatment-induced changes that may affect the diagnosis of recurrent laryngeal carcinoma, the assessment of predictive markers, and the response to treatment with immune checkpoint inhibitors. Radiotherapy induces profound modifications that are strictly related to necrosis of different tissue components, fibrosis, and damage of the tumor vessels. Postradiotherapy recurrent/persistent laryngeal squamous cell carcinoma typically presents a discohesive growth pattern within a fibrotic background associated with significant changes of the tumor immune microenvironment, with both important immunosuppressive and immunostimulatory effects. Overall, the increase of immunoregulatory cells and immune checkpoints such as CTLA-4, TIM-3, PD-1, and PD-L1 induced by radiotherapy and chemotherapy strongly supports the use of immune checkpoint inhibitors in recurrent/persistent laryngeal carcinoma. Future studies aiming to identify predictive factors of the response to immune checkpoint inhibitors should consider such treatment-induced modifications.

New and emerging drugs for the treatment of advanced cutaneous squamous cell carcinoma

INTRODUCTION

Cutaneous squamous cell carcinoma (CSCC) is the second most common form of human cancer. Treatment of locally advanced and/or recurrent CSCC is often challenging. A subset of patients are not candidates for curative-intent therapies due to extent of loco-regional disease, refractoriness to prior local therapy, or presence of distant metastasis.

AREAS COVERED

Traditionally, CSCC has been treated with surgery and/or radiotherapy, but in some instances, local therapies can lead to significant functional morbidity or are no longer feasible. Until 2018, systemic therapy options to treat patients with advanced CSCC were limited. Recently, clinical studies have shown activity of Immune Checkpoint Inhibitors (ICI) in patients with advanced CSCC. This article reviews the current systemic therapy options for CSCC with a focus on ICI and emerging promising therapies in the treatment of this challenging disease.

EXPERT OPINION

ICI is currently the most effective and tolerable systemic therapy in the treatment of non-immunosuppressed advanced CSCC and can lead to cure in a subset of patients. Combinatorial therapies to overcome resistance to ICI may further increase the proportion of patients who will benefit from ICI and may help improve the quantity and quality of life of patients affected by this disease.

Randomized Phase II Trial of Ficlatuzumab With or Without Cetuximab in Pan-Refractory, Recurrent/Metastatic Head and Neck Cancer

PURPOSE

Primary or acquired resistance to cetuximab, an antiepidermal growth factor receptor monoclonal antibody (mAb), minimizes its utility in recurrent/metastatic head and neck squamous cell carcinoma (HNSCC). Aberrant hepatocyte growth factor/cMet pathway activation is an established resistance mechanism. Dual pathway targeting may overcome resistance.

PATIENTS AND METHODS

This multicenter, randomized, noncomparative phase II study evaluated ficlatuzumab, an antihepatocyte growth factor mAb, with or without cetuximab in recurrent/metastatic HNSCC. The primary end point was median progression-free survival (PFS); an arm met significance criteria if the lower bound of the 90% CI excluded the historical control of 2 months. Key eligibility criteria were HNSCC with known human papillomavirus (HPV) status, cetuximab resistance (progression within 6 months of exposure in the definitive or recurrent/metastatic setting), and resistance to platinum and anti-PD-1 mAb. Secondary end points included objective response rate (ORR), toxicity, and the association of HPV status and cMet overexpression with efficacy. Continuous Bayesian futility monitoring was used.

RESULTS

From 2018 to 2020, 60 patients were randomly assigned and 58 were treated. Twenty-seven versus 33 patients were allocated to monotherapy versus combination. Arms were balanced for major prognostic factors. The monotherapy arm closed early for futility. The combination arm met prespecified significance criteria with a median PFS of 3.7 months (lower bound 90% CI, 2.3 months; P = .04); the ORR was 6 of 32 (19%), including two complete and four partial responses. Exploratory analyses were limited to the combination arm: the median PFS was 2.3 versus 4.1 months (P = .03) and the ORR was 0 of 16 (0%) versus 6 of 16 (38%; P = .02) in the HPV-positive versus HPV-negative subgroups, respectively. cMet overexpression was associated with reduced hazard of progression in HPV-negative but not HPV-positive disease (P interaction = .02).

CONCLUSION

The ficlatuzumab-cetuximab arm met significance criteria for PFS and warrants phase III development. HPV-negative HNSCC merits consideration as a selection criterion.

The natural killer cell immunotherapy platform: an overview of the landscape of clinical trials in liquid and solid tumors

The translation of natural killer (NK) cells to the treatment of malignant disease has made significant progress in the last few decades. With a variety of available sources and improvements in both in vitro and in vivo NK cell expansion, the NK cell immunotherapy platform has come into its own. The enormous effort continues to further optimize this platform, including ways to enhance NK cell persistence, trafficking to the tumor microenvironment, and cytotoxicity. As this effort bears fruit, it is translated into a plethora of clinical trials in patients with advanced malignancies. The adoptive transfer of NK cells, either as a standalone therapy or in combination with other immunotherapies, has been applied for the treatment of both liquid and solid tumors, with numerous early-phase trials showing promising results. This review aims to summarize the key advantages of NK cell immunotherapy, highlight several of the current approaches being taken for its optimization, and give an overview of the landscape of clinical trials translating this platform into clinic.

MicroRNA-206 in human cancer: Mechanistic and clinical perspectives

MicroRNAs (miRNAs), small non-coding RNAs approximately 20-25 nt in length, play important roles via directly binding to the corresponding 3' UTR of target mRNAs. Recent research has shown that miRNAs cover a wide range of diseases, including several types of cancer. It is interesting to note that miR-206 operates as a tumor suppressor and is downregulated in abundant cancer types, such as breast cancer, lung cancer, colorectal cancer, and so forth. Interestingly, a growing number of studies have also reported that miR-206 could function as an oncogene and promote tumor cell proliferation. Thereby, miR-206 may act as either oncogenes or tumor suppressors under certain conditions. In addition, it was widely acknowledged that restoring tumor-suppressor miR-206 has emerged as an unconventional cancer therapy strategy. Therefore, miR-206 might be a newfangled procedure for achieving a more significant treatment outcome for cancer patients. This review summarizes the role of miR-206 in several cancer types and the contributions made between miR-206 and the diagnosis, treatment, and drug resistance of solid tumors.

Recapitulating the Pharmacological Interactions of Cetuximab with Sunitinib and Cisplatin in Head and Neck Carcinoma Cells in vitro

INTRODUCTION

Cisplatin is extensively used in the treatment of head and neck carcinomas. Cetuximab combination therapy is employed in recurrent and metastatic settings. Sunitinib showed positive results in the treatment of head and neck carcinomas, both as monotherapy or in combination with cetuximab. Nonetheless, the mechanism governing these pharmacological interactions is largely unresolved. This study investigates the impact of cetuximab on the cytotoxicity of cisplatin and sunitinib using cells representative of head and neck carcinoma and the oral epithelium.

METHODS

The uptake and efflux activities of cells were determined using the prototypical fluorescent substrates 4-[4-[dimethylamino]styryl)-1-methyl pyridinium iodide, Hoechst 33342, and calcein-AM in the presence or absence of specific inhibitors in cells pretreated with cetuximab. The expression of key uptake and efflux drug transporters was analyzed using qPCR and immunofluorescence. Cisplatin and sunitinib cytotoxicities after cetuximab pretreatment were evaluated using the PrestoBlue viability assay.

RESULTS

Both tumor and nontumor cells showed significant active drug transport activity. Cetuximab substantially deregulated the expression of key transporters involved in drug resistance in head and neck cancer cells. Transporter expression in the nontumor cell was unaffected. Upon cetuximab pretreatment, the half maximal effective toxic concentration of cisplatin was reduced by 0.75-fold and sunitinib by 0.82-fold in cancer cells. Nontumor cells were not sensitive to cisplatin or sunitinib under the conditions tested.

CONCLUSION

Cetuximab regulates the expression and activity of key membrane drug transporters in head and neck cancer cells, involved in drug resistance. The deregulation of the transport mechanism behind cisplatin and sunitinib uptake reverses drug resistance and enhances the cytotoxicity of both drugs.

An Inflammatory Signature to Predict the Clinical Benefit of First-Line Cetuximab Plus Platinum-Based Chemotherapy in Recurrent/Metastatic Head and Neck Cancer

Epidermal growth factor receptor (EGFR) pathway has been shown to play a crucial role in several inflammatory conditions and host immune-inflammation status is related to tumor prognosis. This study aims to evaluate the prognostic significance of a four-gene inflammatory signature in recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients treated with the EGFR inhibitor cetuximab plus chemotherapy. The inflammatory signature was assessed on 123 R/M HNSCC patients, enrolled in the multicenter trial B490 receiving first-line cetuximab plus platinum-based chemotherapy. The primary endpoint of the study was progression free survival (PFS), while secondary endpoints were overall survival (OS) and objective response rate (ORR). The patient population was subdivided into 3 groups according to the signature score groups. The four-genes-signature proved a significant prognostic value, resulting in a median PFS of 9.2 months in patients with high vs. 6.2 months for intermediate vs. 3.9 months for low values (p = 0.0016). The same findings were confirmed for OS, with median time of 18.4, 13.4, and 7.5 months for high, intermediate, and low values of the score, respectively (p = 0.0001). When ORR was considered, the signature was significantly higher in responders than in non-responders (p = 0.0092), reaching an area under the curve (AUC) of 0.65 (95% CI: 0.55–0.75). Our findings highlight the role of inflammation in the response to cetuximab and chemotherapy in R/M-HNSCC and may have translational implications for improving treatment selection.

The prognostic impact of the immune signature in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous group of tumors that retain their poor prognosis despite recent advances in their standard of care. As the involvement of the immune system against HNSCC development is well-recognized, characterization of the immune signature and the complex interplay between HNSCC and the immune system could lead to the identification of novel therapeutic targets that are required now more than ever. In this study, we investigated RNA sequencing data of 530 HNSCC patients from The Cancer Genome Atlas (TCGA) for which the immune composition (CIBERSORT) was defined by the relative fractions of 10 immune-cell types and expression data of 45 immune checkpoint ligands were quantified. This initial investigation was followed by immunohistochemical (IHC) staining for a curated selection of immune cell types and checkpoint ligands markers in tissue samples of 50 advanced stage HNSCC patients. The outcome of both analyses was correlated with clinicopathological parameters and patient overall survival. Our results indicated that HNSCC tumors are in close contact with both cytotoxic and immunosuppressive immune cells. TCGA data showed prognostic relevance of dendritic cells, M2 macrophages and neutrophils, while IHC analysis associated T cells and natural killer cells with better/worse prognostic outcome. HNSCC tumors in our TCGA cohort showed differential RNA over- and underexpression of 28 immune inhibitory and activating checkpoint ligands compared to healthy tissue. Of these, CD73, CD276 and CD155 gene expression were negative prognostic factors, while CD40L, CEACAM1 and Gal-9 expression were associated with significantly better outcomes. Our IHC analyses confirmed the relevance of CD155 and CD276 protein expression, and in addition PD-L1 expression, as independent negative prognostic factors, while HLA-E overexpression was associated with better outcomes. Lastly, the co-presence of both (i) CD155 positive cells with intratumoral NK cells; and (ii) PD-L1 expression with regulatory T cell infiltration may hold prognostic value for these cohorts. Based on our data, we propose that CD155 and CD276 are promising novel targets for HNSCC, possibly in combination with the current standard of care or novel immunotherapies to come.

Augmenting NK cell-based immunotherapy by targeting mitochondrial apoptosis

Interest in harnessing natural killer (NK) cells for cancer immunotherapy is rapidly growing. However, efficacy of NK cell-based immunotherapy remains limited in most trials. Strategies to augment the killing efficacy of NK cells are thus much needed. In the current study, we found that mitochondrial apoptosis (mtApoptosis) pathway is essential for efficient NK killing, especially at physiologically relevant effector-to-target ratios. Furthermore, NK cells can prime cancer cells for mtApoptosis and mitochondrial priming status affects cancer-cell susceptibility to NK-mediated killing. Interestingly, pre-activating NK cells confers on them resistance to BH3 mimetics. Combining BH3 mimetics with NK cells synergistically kills cancer cells in vitro and suppresses tumor growth in vivo. The ideal BH3 mimetic to use in such an approach can be predicted by BH3 profiling. We herein report a rational and precision strategy to augment NK-based immunotherapy, which may be adaptable to T cell-based immunotherapies as well.

Immunotherapy and Targeted Therapy in the Management of Oral Cancers

Oral cancers (OCs), being one of the frequent malignancies in the head and neck region, need prompt diagnosis and treatment. Apart from basic therapeutic modalities, immunotherapy has now been utilized as a novel approach to combat the disease. With the comprehension of the strategies adopted by cancer cells to evade the immune elimination by the body's immune system, targeted immunotherapies have now become the core area of research. The immune expression of epidermal growth factor receptor (EGFR), programmed cell death protein ligand-1 (PDL-1), etc., are enhanced in OC and have been associated with evasion of the immune system. Targeted immunotherapies now include monoclonal antibodies targeting EGFR like cetuximab and panitumumab, programmed cell death-1 (PD-1) inhibitors like pembrolizumab, cemiplimab, and nivolumab, and PD-L1 inhibitors like atezolizumab, avelumab, and durvalumab. Targeted immunotherapies like chimeric antigen receptor T-cell treatment and small molecule inhibitors are in several clinical trials tried as monotherapy and adjuvant immunotherapy and have shown promising results. Other immunothera-peutic approaches such as cytokines like interferons or interleukins, vaccines, and gene therapy have also been an area of research for the management of OC. However, the cautious selection of appropriate patients with specific immune characteristics as a candidate for immunotherapeutic agents is a crucial component of targeted immunotherapy. This article elaborates on the immune contexture of oral cancer cells, the mechanism of immune evasion by cancer cells, targets for immunotherapies, existent immunotherapeutic agents, and prospects in the field of immunotherapy.

Immunotherapy Approaches in HPV-Associated Head and Neck Cancer

Immunotherapy approaches for head and neck squamous cell carcinoma (HNSCC) are rapidly advancing. Human papillomavirus (HPV) has been identified as a causative agent in a subset of oropharyngeal cancers (OPC). HPV-positive OPC comprises a distinct clinical and pathologic disease entity and has a unique immunophenotype. Immunotherapy with anti-PD1 checkpoint inhibitors has exhibited improved outcomes for patients with advanced HNSCC, irrespective of HPV status. To date, the clinical management of HPV-positive HNSCC and HPV-negative HNSCC has been identical, despite differences in the tumor antigens, immune microenvironment, and immune signatures of these two biologically distinct tumor types. Numerous clinical trials are underway to further refine the application of immunotherapy and develop new immunotherapy approaches. The aim of this review is to highlight the developing role of immunotherapy in HPV-positive HNSCC along with the clinical evidence and preclinical scientific rationale behind emerging therapeutic approaches, with emphasis on promising HPV-specific immune activators that exploit the universal presence of foreign, non-self tumor antigens.

NK Cell-Dependent Antibody-Mediated Immunotherapy Is Improved In Vitro and In Vivo When Combined with Agonists for Toll-like Receptor 2 in Head and Neck Cancer Models

The immunosuppressive character of head and neck cancers may explain the relatively low response rates to antibody therapy targeting a tumor antigen, such as cetuximab, and anti-PD-1 checkpoint inhibition. Immunostimulatory agents that overcome tumor-derived inhibitory signals could augment therapeutic efficacy, thereby enhancing tumor elimination and improving patient survival. Here, we demonstrate that cetuximab treatment combined with immunostimulatory agonists for Toll-like receptor (TLR) 2 induces profound immune responses. Natural killer (NK) cells, isolated from healthy individuals or patients with head and neck cancer, harbored enhanced cytotoxic capacity and increased tumor-killing potential in vitro. Additionally, combination treatment increased the release of several pro-inflammatory cytokines and chemokines by NK cells. Tumor-bearing mice that received cetuximab and the TLR2 ligand Pam3CSK4 showed increased infiltration of immune cells into the tumors compared to mice that received cetuximab monotherapy, resulting in a significant delay in tumor growth or even complete tumor regression. Moreover, combination treatment resulted in improved overall survival in vivo. In conclusion, combining tumor-targeting antibody-based immunotherapy with TLR stimulation represents a promising treatment strategy to improve the clinical outcomes of cancer patients. This treatment could well be applied together with other therapeutic strategies such as anti-PD-(L)1 checkpoint inhibition to further overcome immunosuppression.

The Right Partner in Crime: Unlocking the Potential of the Anti-EGFR Antibody Cetuximab via Combination With Natural Killer Cell Chartering Immunotherapeutic Strategies

Cetuximab has an established role in the treatment of patients with recurrent/metastatic colorectal cancer and head and neck squamous cell cancer (HNSCC). However, the long-term effectiveness of cetuximab has been limited by the development of acquired resistance, leading to tumor relapse. By contrast, immunotherapies can elicit long-term tumor regression, but the overall response rates are much more limited. In addition to epidermal growth factor (EGFR) inhibition, cetuximab can activate natural killer (NK) cells to induce antibody-dependent cellular cytotoxicity (ADCC). In view of the above, there is an unmet need for the majority of patients that are treated with both monotherapy cetuximab and immunotherapy. Accumulated evidence from (pre-)clinical studies suggests that targeted therapies can have synergistic antitumor effects through combination with immunotherapy. However, further optimizations, aimed towards illuminating the multifaceted interplay, are required to avoid toxicity and to achieve better therapeutic effectiveness. The current review summarizes existing (pre-)clinical evidence to provide a rationale supporting the use of combined cetuximab and immunotherapy approaches in patients with different types of cancer.

Current Aspects and Future Considerations of EGFR Inhibition in Locally Advanced and Recurrent Metastatic Squamous Cell Carcinoma of the Head and Neck

Simple Summary

Squamous cell carcinoma of the head and neck (SCCHN) is a debilitating disease that affects hundreds of thousands of individuals worldwide and has a high mortality rate. Mainstay treatment largely consists of surgery, radiation, and chemotherapy which has been met with significant morbidity. The epidermal growth factor receptor is one that which plays a major role in cell signaling and has been extensively studied in locally advanced (LA) and recurrent metastatic (RM) SCCHN. This review paper details the major roles of the epidermal growth factor receptor (EGFR), previous and current EGFR inhibition therapeutics, resistance mechanisms, and the possible integration of immunotherapy and EGFR inhibition in this disease process.

Abstract

Recurrent metastatic (RM) and locally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN) are devasting disease states with limited therapeutic options and poor overall survival. Targeting the epidermal growth factor receptor (EGFR) is one area that has helped improve outcomes in this disease. Anti-EGFR based therapies have been shown to improve overall survival and mitigate the significant toxicities incurred from standard radiation, chemotherapy, and/or surgical options. Cetuximab, the most well-studied anti-EGFR monoclonal antibody, has demonstrated a positive impact on outcomes for RM and LA SCCHN. However, the development of early resistance to cetuximab highlights the need for a wider arsenal of therapy for RM and LA diseases. The use of immune checkpoint inhibitors has recently transformed the treatment of recurrent SCCHN. Drugs such as pembrolizumab and nivolumab have demonstrated success in recent clinical trials and have been approved for the treatment of advanced disease. Given the positive results of both EGFR targeted agents and immune checkpoint inhibitors, ongoing trials are studying their synergistic effects.

MHC Class I Deficiency in Solid Tumors and Therapeutic Strategies to Overcome It

It is now well accepted that the immune system can control cancer growth. However, tumors escape immune-mediated control through multiple mechanisms and the downregulation or loss of major histocompatibility class (MHC)-I molecules is a common immune escape mechanism in many cancers. MHC-I molecules present antigenic peptides to cytotoxic T cells, and MHC-I loss can render tumor cells invisible to the immune system. In this review, we examine the dysregulation of MHC-I expression in cancer, explore the nature of MHC-I-bound antigenic peptides recognized by immune cells, and discuss therapeutic strategies that can be used to overcome MHC-I deficiency in solid tumors, with a focus on the role of natural killer (NK) cells and CD4 T cells.

Biological Therapy with Complementary and Alternative Medicine in Innocuous Integrative Oncology: A Case of Cervical Cancer

Good medicine is based on good science, inquiry driven and open to new paradigms. For a complex disease such as cancer, a complex treatment regime that is well structured and multifactorial is indispensable. In the present day, Complementary and Alternative Medicine (CAM) therapies are being used frequently for cancer, alongside modern biological therapies and allopathic medicine, in what is called integrative oncology. In all conscience, the use of natural, less invasive interventions whenever possible is ideal. However, a comprehensive understanding of not only the etiopathology of individual cancers, but also the detailed genetic and epigenetic characteristics, the cancer hallmarks, that clearly show the blueprint of the cancer phenotype is a requisite. Different tumors have a common behavioral pattern, but their specific features at the genetic and epigenetic levels vary to a great extent. Henceforth, with so many failed attempts to therapy, drug formulations and combinations need a focused pre-assessment of the inherent features of individual cancers to destroy the tumors holistically by targeting these features. This review therefore presents innocuous therapeutic regimes by means of CAM and integrative medicine approaches that can specifically target the hallmarks of cancer, using the case of cervical cancer.