The interaction of interleukin-8 and PTEN inactivation promotes the malignant progression of head and neck squamous cell carcinoma via the STAT3 pathway

The future of interleukin gene therapy in head and neck cancers

INTRODUCTION

Head and neck cancer (HNC), primarily head and neck squamous cell carcinomas, originates from the squamous epithelium in areas like the oral cavity, lip, larynx, and oropharynx. With high morbidity impacting critical functions, combined treatments like surgery, radiation, and chemotherapy often fall short in advanced stages, highlighting the need for innovative therapies.

AREAS COVERED

This review critically evaluates interleukin (IL) gene therapy for treating HNC. The discussion extends to key ILs in HNC, various gene therapy techniques and delivery methods. We particularly focus on the application of IL-2, IL-12, and IL-24 gene therapies, examining their mechanisms and outcomes in preclinical studies and clinical trials. The final sections address IL gene therapy challenges in HNC, exploring solutions and critically assessing future therapeutic directions.

EXPERT OPINION

Despite advancements in genomic and immunotherapy, significant challenges in HNC treatment persist, primarily due to the immunosuppressive nature of the tumor microenvironment and the adverse effects of current therapies. The therapeutic efficacy of IL gene therapy hinges on overcoming these hurdles through refined delivery methods that ensure targeted, tumor-specific gene expression. Future strategies should focus on refining gene delivery methods and combining IL gene therapy with other treatments to optimize efficacy and minimize toxicity.

Tumor-derived extracellular vesicles in the immune microenvironment of head and neck squamous cell carcinoma: Foe or future?

Head and neck squamous cell carcinoma (HNSCC) is considered a "cold tumor" due to its suppressive immune microenvironment, and is associated with a poor prognosis. Tumor-derived extracellular vesicles (EVs) play an essential role in the tumor microenvironment and mediate intercellular communications. EVs have been proven to be key immune regulators involved in antitumor immune responses and escape from immune surveillance. Tumor-derived EVs favor the formation of an immunosuppressive tumor microenvironment by regulating the differentiation, proliferation and activation of innate and adaptive immune effector cells, as well as myeloid cells, acting as a "foe" in the microenvironment. However, EVs are also valuable for predicting and improving the prognosis of HNSCC, and represent hope for future treatments. In this review, we summarize the impact of HNSCC-derived EVs on the immune microenvironment, describe their roles as biomarkers and for drug delivery in disease monitoring and treatment. We provide insights into important areas for future research and identify potential therapeutic targets for HNSCC treatment.

RNPS1 stabilizes NAT10 protein to facilitate translation in cancer via tRNA ac4C modification

Existing studies have underscored the pivotal role of N-acetyltransferase 10 (NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma (HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1 (RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6 (ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac4C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel tRNA-ac4C modification sites, thereby providing a potent sequencing tool for tRNA-ac4C research. Our findings expand the repertoire of tRNA ac4C modifications and identify a role of tRNA ac4C in the regulation of mRNA translation in HNSCC.

Modulation of fracture healing by senescence-associated secretory phenotype (SASP): a narrative review of the current literature

The senescence-associated secretory phenotype (SASP) is a generic term for the secretion of cytokines, such as pro-inflammatory factors and proteases. It is a crucial feature of senescent cells. SASP factors induce tissue remodeling and immune cell recruitment. Previous studies have focused on the beneficial role of SASP during embryonic development, wound healing, tissue healing in general, immunoregulation properties, and cancer. However, some recent studies have identified several negative effects of SASP on fracture healing. Senolytics is a drug that selectively eliminates senescent cells. Senolytics can inhibit the function of senescent cells and SASP, which has been found to have positive effects on a variety of aging-related diseases. At the same time, recent data suggest that removing senescent cells may promote fracture healing. Here, we reviewed the latest research progress about SASP and illustrated the inflammatory response and the influence of SASP on fracture healing. This review aims to understand the role of SASP in fracture healing, aiming to provide an important clinical prevention and treatment strategy for fracture. Clinical trials of some senolytics agents are underway and are expected to clarify the effectiveness of their targeted therapy in the clinic in the future. Meanwhile, the adverse effects of this treatment method still need further study.

HPV-Negative and HPV-Positive Oral Cancer Cells Stimulate the Polarization of Neutrophils towards Different Functional Phenotypes In Vitro

High-risk human papillomavirus (HPV) infection is one of the leading causes of oropharyngeal squamous cell carcinoma (OPSCC), while the correlation between HPV and oral squamous cell carcinoma (OSCC) remains controversial. The inflammatory infiltrate involved in these epithelial neoplasms differs based on their association with HPV. HPV- tumors show higher tumor-associated neutrophil (TAN) infiltration. It is believed that TANs can play a dual role in cancer by exerting either anti-tumorigenic or pro-tumorigenic effects. However, the impact of HPV status on neutrophil polarization remains unknown. Therefore, this study aimed to investigate the effect of OSCC cells, both HPV- and HPV16+, on the functional phenotype of neutrophils. Peripheral blood neutrophils were stimulated with supernatants from OSCC cell lines and non-tumorigenic HaCaT keratinocytes transduced with HPV16 E6/E7 oncogenes. Subsequently, cytokine production, cell viability, metabolism, expression of degranulation markers, and PD-L1 expression were evaluated. Our findings demonstrate that in contrast to UPCI:SCC154 (HPV+ OSCC) cells, the SCC-9 (HPV- OSCC) cell line induced a highly activated functional state in neutrophils, which is potentially associated with a pro-tumorigenic effect. The HaCaT 16-E7 supernatant only stimulated the activation of some neutrophil functions. Understanding the complex interplay between neutrophils and their microenvironment has the potential to identify TANs as viable therapeutic targets.

Chronic oxidative stress adaptation in head and neck cancer cells generates slow-cyclers with decreased tumour growth in vivo

BACKGROUND

Reactive oxygen species (ROS) are implicated in cancer therapy and as drivers of microenvironmental tumour cell adaptations. Medical gas plasma is a multi-ROS generating technology that has been shown effective for palliative tumour control in head and neck cancer (HNC) patients before tumour cells adapted to the oxidative stress and growth regressed fatally.

METHODS

In a bedside-to-bench approach, we sought to explore the oxidative stress adaptation in two human squamous cell carcinoma cell lines. Gas plasma was utilised as a putative therapeutic agent and chronic oxidative stress inducer.

RESULTS

Cellular responses of single and multiple treated cells were compared regarding sensitivity, cellular senescence, redox state and cytokine release. Whole transcriptome analysis revealed a strong correlation of cancer cell adaption with increased interleukin 1 receptor type 2 (IL1R2) expression. Using magnetic resonance imaging, tumour growth and gas plasma treatment responses of wild-type (WT) and repeatedly exposed (RE) A431 cells were further investigated in a xenograft model in vivo. RE cells generated significantly smaller tumours with suppressed inflammatory secretion profiles and increased epidermal growth factor receptor (EGFR) activity showing significantly lower gas plasma sensitivity until day 8.

CONCLUSIONS

Clinically, combination treatments together with cetuximab, an EGFR inhibitor, may overcome acquired oxidative stress resistance in HNC.

Macrophage Profiling in Head and Neck Cancer to Improve Patient Prognosis and Assessment of Cancer Cell-Macrophage Interactions Using Three-Dimensional Coculture Models

Tumor-associated macrophages are key components of the tumor microenvironment and play important roles in the progression of head and neck cancer, leading to the development of effective strategies targeting immune cells in tumors. Our study demonstrated the prognostic potential of a new scoring system (Macroscore) based on the combination of the ratio and the sum of the high and low densities of M1 (CD80+) and M2 (CD163+) macrophages in a series of head and neck cancer patients, including a training population (n = 54) and a validation population (n = 19). Interestingly, the Macroscore outperformed TNM criteria and p16 status, showing a significant association with poor patient prognosis, and demonstrated significant predictive value for overall survival. Additionally, 3D coculture spheroids were established to analyze the crosstalk between cancer cells and monocytes/macrophages. Our data revealed that cancer cells can induce monocyte differentiation into protumoral M2 macrophages, creating an immunosuppressive microenvironment. This coculture also induced the production of immunosuppressive cytokines, such as IL10 and IL8, known to promote M2 polarization. Finally, we validated the ability of the macrophage subpopulations to induce apoptosis (M1) or support proliferation (M2) of cancer cells. Overall, our research highlights the potential of the Macroscore as a valuable prognostic biomarker to enhance the clinical management of patients and underscores the relevance of a spheroid model in gaining a better understanding of the mechanisms underlying cancer cell-macrophage interactions.

Matrix Metalloproteinase 9 Induced in Esophageal Squamous Cell Carcinoma Cells via Close Contact with Tumor-Associated Macrophages Contributes to Cancer Progression and Poor Prognosis

Tumor-associated macrophages (TAMs) contribute to disease progression in various cancers, including esophageal squamous cell carcinoma (ESCC). We have previously used an indirect co-culture system between ESCC cell lines and macrophages to analyze their interactions. Recently, we established a direct co-culture system to closely simulate actual ESCC cell-TAM contact. We found that matrix metalloproteinase 9 (MMP9) was induced in ESCC cells by direct co-culture with TAMs, not by indirect co-culture. MMP9 was associated with ESCC cell migration and invasion, and its expression was controlled by the Stat3 signaling pathway in vitro. Immunohistochemical analyses revealed that MMP9 expression in cancer cells at the invasive front ("cancer cell MMP9") was related to high infiltration of CD204 positive M2-like TAMs (p < 0.001) and was associated with worse overall and disease-free survival of patients (p = 0.036 and p = 0.038, respectively). Furthermore, cancer cell MMP9 was an independent prognostic factor for disease-free survival. Notably, MMP9 expression in cancer stroma was not associated with any clinicopathological factors or patient prognoses. Our results suggest that close interaction with TAMs infiltrating in cancer stroma or cancer nests induces MMP9 expression in ESCC cells, equipping them with more malignant features.

Autophagy modulators influence the content of important signalling molecules in PS-positive extracellular vesicles

Extracellular vesicles (EVs) are important mediators of intercellular communication in the tumour microenvironment. Many studies suggest that cancer cells release higher amounts of EVs exposing phosphatidylserine (PS) at the surface. There are lots of interconnections between EVs biogenesis and autophagy machinery. Modulation of autophagy can probably affect not only the quantity of EVs but also their content, which can deeply influence the resulting pro-tumourigenic or anticancer effect of autophagy modulators. In this study, we found that autophagy modulators autophinib, CPD18, EACC, bafilomycin A1 (BAFA1), 3-hydroxychloroquine (HCQ), rapamycin, NVP-BEZ235, Torin1, and starvation significantly alter the composition of the protein content of phosphatidylserine-positive EVs (PS-EVs) produced by cancer cells. The greatest impact had HCQ, BAFA1, CPD18, and starvation. The most abundant proteins in PS-EVs were proteins typical for extracellular exosomes, cytosol, cytoplasm, and cell surface involved in cell adhesion and angiogenesis. PS-EVs protein content involved mitochondrial proteins and signalling molecules such as SQSTM1 and TGFβ1 pro-protein. Interestingly, PS-EVs contained no commonly determined cytokines, such as IL-6, IL-8, GRO-α, MCP-1, RANTES, and GM-CSF, which indicates that secretion of these cytokines is not predominantly mediated through PS-EVs. Nevertheless, the altered protein content of PS-EVs can still participate in the modulation of the fibroblast metabolism and phenotype as p21 was accumulated in fibroblasts influenced by EVs derived from CPD18-treated FaDu cells. The altered protein content of PS-EVs (data are available via ProteomeXchange with identifier PXD037164) also provides information about the cellular compartments and processes that are affected by the applied autophagy modulators. Video Abstract.

STAT3 signaling in pancreatic ductal adenocarcinoma: a candidate therapeutic target

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with a poor prognosis which is lethal in over 90% of cases despite the standard therapies. Mainly activated by Janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3) is a key transcription factor, capable of exerting the expression of multitude of genes involved in survival. Moreover, STAT3 activity is regulated by the interleukin 28 receptor α (IL28RA) and glutathione s-transferase mu-3 (GSTM3), up-regulation of both contributes to the invasiveness of pancreatic cancer cells. In this regard, STAT3 overactivity has an important pathogenic role in the development of PDAC as it is associated with enhanced cell proliferation, survival, angiogenesis, and metastasis. STAT3-associated expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase 3 and 9 are implicated in the angiogenic and metastatic behavior of the PDAC. Multitude of evidence underline the protective role of STAT3 inhibition against PDAC both in cell cultures and in tumor grafts. However, specific inhibition of STAT3 was not feasible until recently, when a selective potent chemical STAT3 inhibitor, termed N4, were developed and it turned out to be highly effective against PDAC in vitro, as well as in vivo. This review aims to discuss the most recent advances in our understanding of STAT3 role in the pathogenesis of PDAC and its therapeutic applications.

BEST1 Positive Monocytes in Circulation: Visualize Intratumoral Crosstalk between Cancer Cells and Monocytes

Head and neck squamous cell carcinomas (HNSCCs) are characterized by an abundance of monocytes and macrophages recruited from the peripheral blood. However, it has not been determined whether these infiltrated cells can be released back into circulation with a tumor-associated neobiosignature. This study reports that Bestrophin1 (BEST1), a component protein of Ca²⁺ -activated Cl^- channels (CaCCs), is highly expressed on classical monocytes in the peripheral blood of HNSCC patients. This is due to monocyte education by tumor cells, in which tumoral VEGF-A upregulates BEST1 expression on monocytes through the MEK-ERK-ELK1 pathway. This leads to improved secretion of IL-6 and IL-8, which promotes tumor cell proliferation. This work also finds that BEST1 facilitates the motility of monocytes, contributing to the migration of these cells back into circulation. These results suggest that the expression of BEST1 on peripheral monocytes may be a potential tool for monitoring tumor progression, and opens up the possibility of searching for cancer biomarkers on monocytes rather than on the tumor or its products.

Targeted blockade of interleukin-8 negates metastasis and chemoresistance via Akt/Erk-NFκB axis in oral cancer

BACKGROUND

The tumor microenvironment plays a significant role in tumor growth, metastasis and chemoresistance via dysregulated signaling pathways. Toward this, an inflammatory chemokine, interleukin-8 (IL-8), is overexpressed in various cancers and is involved in tumor progression and chemoresistance. However, the mechanistic role of IL-8 in mediating metastasis and chemoresistance in oral squamous cell carcinoma (OSCC) is not known.

METHODS AND RESULTS

In the present study, we evaluated the effect of IL-8 in regulating metastasis as well as chemoresistance in OSCC cell lines. For this, IL-8 was blocked exogenously using neutralizing IL-8 monoclonal antibody and IL-8 levels were enhanced by exogenous supply of recombinant human IL-8 (rhIL-8) to OSCC cells. The epithelial-to-mesenchymal transition (EMT) was evaluated using qPCR, migration by scratch/wound healing assay and invasion ability using transwell assay. rIL-8 induced chemoresistance was studied by apoptosis assay and the nuclear localization of NFκB using immunocytochemistry. IL-8 was significantly overexpressed in OSCC patients and cell lines. While exogenous blockade of IL-8 significantly reduced EMT, migration and invasion potential in OSCC cells, IL-8 overexpression upregulated these cellular traits thereby confirming the role of IL-8 in OSCC metastasis. Exogenous blockade of IL-8 also reversed chemoresistance in cisplatin resistant OSCC subline via NFκB signaling.

CONCLUSION

IL-8 plays a crucial role in OSCC metastasis and its targeted blockade can help in management of cisplatin resistance.

Dicer Suppresses Hepatocellular Carcinoma via Interleukin-8 Pathway

Background

Elevated level of interleukin-8 (IL-8) promotes hepatocellular carcinoma (HCC) development and contributes to poor prognosis. Previously, we have proved that Dicer inhibits HCC progression. In this study, we evaluated the potential interaction between IL-8 and Dicer as well as their influence on HCC.

Methods

Hepatocellular carcinoma cells of SMMC-7721 were divided into 2 groups for subsequent analysis: pCMV-Dicer group for Dicer-overexpressing lentivirus transfected cells (pCMV-Dicer cells) and pCMV-NC group for empty lentivirus transfected cells (pCMV-NC cells). Cell Counting kit-8 (CCK8), wound healing, and transwell were used to evaluate the inhibitory effect of Dicer overexpression on proliferation, migration, and invasion of HCC cells. The level of IL-8 was measured by flow cytometry bead-based immunoassays. Male nude BALB/c mice injected with pCMV-Dicer or pCMV-NC cell suspensions was used for transplant of HCC tumor.

Results

We found that the secretion of IL-8 was reduced in the medium of pCMV-Dicer cells (P = .027). Recombinant human IL-8 (rhIL-8) reversed the inhibitory effect of Dicer on proliferation (P < .01), migration (P = .003), and invasion (P = .001), whereas IL-8 inhibitor of reparixin enhanced inhibitory effect of Dicer on proliferation (P < .05), migration (P = .008), and invasion (P = .000). Lenvatinib downregulated the IL-8 level of HCC cells (P = .000) as well as promote Dicer-induced inhibition for HCC cells referring to proliferation (P < .05), migration (P = .000), and invasion (P = .000). Animal experiments also demonstrated that Dicer cooperated with lenvatinib to inhibit the growth of HCC tumors (P < .05).

Conclusions

Dicer cooperated with lenvatinib to inhibit HCC growth via downregulating IL-8, and Dicer displayed its potential capability to enhance the anti-tumor effect of lenvatinib.

Neutrophils: Musketeers against immunotherapy

Neutrophils, the most copious leukocytes in human blood, play a critical role in tumorigenesis, cancer progression, and immune suppression. Recently, neutrophils have attracted the attention of researchers, immunologists, and oncologists because of their potential role in orchestrating immune evasion in human diseases including cancer, which has led to a hot debate redefining the contribution of neutrophils in tumor progression and immunity. To make this debate fruitful, this review seeks to provide a recent update about the contribution of neutrophils in immune suppression and tumor progression. Here, we first described the molecular pathways through which neutrophils aid in cancer progression and orchestrate immune suppression/evasion. Later, we summarized the underlying molecular mechanisms of neutrophil-mediated therapy resistance and highlighted various approaches through which neutrophil antagonism may heighten the efficacy of the immune checkpoint blockade therapy. Finally, we have highlighted several unsolved questions and hope that answering these questions will provide a new avenue toward immunotherapy revolution.

Long Noncoding RNA LINC00467: Role in Various Human Cancers

Intricate genetic mutations promote the progression of different cancer types. Long noncoding RNAs (lncRNAs) have been widely demonstrated to participate in the genomic activities of various human cancers. Long intergenic non-coding RNA 467 (LINC00467) is an upregulated lncRNA in diverse diseases, especially in several types of cancers. Functional experiments of LINC00467 revealed that LINC00467 overexpression enhanced cell chemoresistance, proliferation, migration, and invasion in several types of cancers. Moreover, overexpressed LINC00467 was associated with a poor clinical prognosis. The present evidence suggests that LINC00467 may serve as a promising prognostic indicator and become a novel cancer therapeutic target. In this review, we introduce the biologic functions of lncRNAs and describe the molecular mechanism and clinical significance of LINC00467 in detail.

STAT3 pathway in cancers: Past, present, and future

Signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, discovered in the cytoplasm of almost all types of mammalian cells, plays a significant role in biological functions. The duration of STAT3 activation in normal tissues is a transient event and is strictly regulated. However, in cancer tissues, STAT3 is activated in an aberrant manner and is induced by certain cytokines. The continuous activation of STAT3 regulates the expression of downstream proteins associated with the formation, progression, and metastasis of cancers. Thus, elucidating the mechanisms of STAT3 regulation and designing inhibitors targeting the STAT3 pathway are considered promising strategies for cancer treatment. This review aims to introduce the history, research advances, and prospects concerning the STAT3 pathway in cancer. We review the mechanisms of STAT3 pathway regulation and the consequent cancer hallmarks associated with tumor biology that are induced by the STAT3 pathway. Moreover, we summarize the emerging development of inhibitors that target the STAT3 pathway and novel drug delivery systems for delivering these inhibitors. The barriers against targeting the STAT3 pathway, the focus of future research on promising targets in the STAT3 pathway, and our perspective on the overall utility of STAT3 pathway inhibitors in cancer treatment are also discussed.

Plasma secretome analyses identify IL-8 and nitrites as predictors of poor prognosis in nasopharyngeal carcinoma patients

Predicting tumor recurrence and death in patients with nasopharyngeal carcinoma (NPC) remains to date challenging. We here analyzed the plasmatic secretomes of NPC untreated and relapsing patients, and explored possible correlations with the clinical and pathological features and survival characteristics of the corresponding patient cohorts, with the aim of identifying novel prognostic biomarkers. This study included 27 controls, 45 untreated NPC and 11 relapsed patients. A set of 14 plasma cytokines were analyzed using Millipore multiplex assay. Nitrites were assessed by Griess method. A comparative analysis of each groups' secretome showed upregulation of IL-8, IL-12p70, IL-10 and IP-10 in untreated patients, and of IL-6, IL-10, MCP-1 and IP-10 in relapsing patients. Nitrites significantly correlated with IL-8 during relapse. Secretomes' network analyses revealed prevalence of high correlations between IL8/IL-17A and IFN-γ/IL12p70 in the control group, between TNF-α/IL-8/IL-6, TNF-α/VEGF/IFN-γ and IL-10/MCP-1 in the untreated group, and between IL-8/IL-6/IL-10, TNF-α/IL-8/IL-6, IL12-p70/VEGF/IL-10/IFN-γ, IL-6/IL-10/IFN-γ and IL-8/IP-10 in the relapse group. IL-12p70, IP-10 and MCP-1 levels respectively associated with gender, age and node metastasis respectively. Recurrence-free survival (RFS) analysis showed that patients presenting High IL-8/Low NO immunological scores presented a combined 80% probability of relapse/death after 53 months (combined log-rank test p = 0.0034; individual p = 0.012 and p = 0.016). Multivariate Cox hazard regression analysis revealed that IL-8 (HR = 7.451; 95% CI [2.398-23.152]; p = 0.001) and treatment type (HR = 0.232; 95% CI 0.072-0.749; p = 0.015) were independent prognostic factors. C&RT decision tree analysis showed that High IL-8/Low NO immunological scores predicted treatment failure in 50% cases starting the 36th month of follow-up (AUC = 1) for all of the studied cases and in 57% cases for patients receiving chemotherapy alone (AUC = 1). Altogether, our results showed that NPC development is accompanied with cytokines deregulation to form specific interaction networks at time of diagnosis and relapse, and demonstrate that High IL-8/Low NO signature may constitute a predictor of poor prognosis which may be useful to improve risk stratification and therapy failure management.

Involvement of microRNA modifications in anticancer effects of major polyphenols from green tea, coffee, wine, and curry

Epidemiological studies have shown that consumption of green tea, coffee, wine, and curry may contribute to a reduced risk of various cancers. However, there are some cancer site-specific differences in their effects; for example, the consumption of tea or wine may reduce bladder cancer risk, whereas coffee consumption may increase the risk. Animal and cell-based experiments have been used to elucidate the anticancer mechanisms of these compounds, with reactive oxygen species (ROS)-based mechanisms emerging as likely candidates. Chlorogenic acid (CGA), curcumin (CUR), epigallocatechin gallate (EGCG), and resveratrol (RSV) can act as antioxidants that activate AMP-activated protein kinase (AMPK) to downregulate ROS, and as prooxidants to generate ROS, leading to the downregulation of NF-κB. Polyphenols can modulate miRNA (miR) expression, with these dietary polyphenols shown to downregulate tumor-promoting miR-21. CUR, EGCG, and RSV can upregulate tumor-suppressing miR-16, 34a, 145, and 200c, but downregulate tumor-promoting miR-25a. CGA, EGCG, and RSV downregulate tumor-suppressing miR-20a, 93, and 106b. The effects of miRs may combine with ROS-mediated pathways, enhancing the anticancer effects of these polyphenols. More precise analysis is needed to determine how the different modulations of miRs by polyphenols relate to the cancer site-specific differences found in epidemiological studies related to the consumption of foods containing these polyphenols.

CXCL8 in Tumor Biology and Its Implications for Clinical Translation

The chemokine CXCL8 has been found to play an important role in tumor progression in recent years. CXCL8 activates multiple intracellular signaling pathways by binding to its receptors (CXCR1/2), and plays dual pro-tumorigenic roles in the tumor microenvironment (TME) including directly promoting tumor survival and affecting components of TME to indirectly facilitate tumor progression, which include facilitating tumor cell proliferation and epithelial-to-mesenchymal transition (EMT), pro-angiogenesis, and inhibit anti-tumor immunity. More recently, clinical trials indicate that CXCL8 can act as an independently predictive biomarker in patients receiving immune checkpoint inhibitions (ICIs) therapy. Preclinical studies also suggest that combined CXCL8 blockade and ICIs therapy can enhance the anti-tumor efficacy, and several clinical trials are being conducted to evaluate this therapy modality.

Multiple Effects of Resveratrol on Osteosarcoma Cell Lines

Osteosarcoma (OS) is the most common primary bone sarcoma affecting the life of pediatric patients. The clinical treatment faces numerous difficulties, including the adverse effects of chemotherapies, chemoresistance, and recurrences. In this study, the effects of resveratrol (RSV), a natural polyphenol, on OS cell lines were investigated to evaluate its action as an adjuvant therapy to the current chemotherapy regimens. RSV exhibited multiple tumor-suppressing activities on OS cell lines, inducing a series of critical events. We found (1) a cell growth inhibition due to an increase in cell distress, which was, in part, due to the involvement of the AKT and caspase-3 pathways, (2) an increase in cellular differentiation due to major gene expression levels of the osteoblastic differentiation genes, (3) an inhibition of IL-6 secretion due to an epigenetic effect on the IL-6 promoter, and (4) an inhibition of OS cells migration related to the decrease in IL-8 secretion levels due to an epigenetic effect on its promoter. Finally, the cotreatment of RSV with doxorubicin and cisplatin increased their cytotoxic effect on OS cells. Although further investigations are mandatory, it seems RSV might be a promising therapeutic adjuvant agent for OS cell treatment, exerting an antitumor effect when combined with chemotherapy.

Interleukin-8 in Melanoma Pathogenesis, Prognosis and Therapy-An Integrated View into Other Neoplasms and Chemokine Networks

Cutaneous melanoma accounts for only about 7% of skin cancers but is causing almost 90% of deaths. Melanoma cells have a distinct repertoire of mutations from other cancers, a high plasticity and degree of mimicry toward vascular phenotype, stemness markers, versatility in evading and suppress host immune control. They exert a significant influence on immune, endothelial and various stromal cells which form tumor microenvironment. The metastatic stage, the leading cause of mortality in this neoplasm, is the outcome of a complex, still poorly understood, cross-talk between tumor and other cell phenotypes. There is accumulating evidence that Interleukin-8 (IL-8) is emblematic for advanced melanomas. This work aimed to present an updated status of IL-8 in melanoma tumor cellular complexity, through a comprehensive analysis including data from other chemokines and neoplasms. The multiple processes and mechanisms surveyed here demonstrate that IL-8 operates following orchestrated programs within signaling webs in melanoma, stromal and vascular cells. Importantly, the yet unknown molecularity regulating IL-8 impact on cells of the immune system could be exploited to overturn tumor fate. The molecular and cellular targets of IL-8 should be brought into the attention of even more intense scientific exploration and valorization in the therapeutical management of melanoma.

Roles of the CXCL8-CXCR1/2 Axis in the Tumor Microenvironment and Immunotherapy

In humans, Interleukin-8 (IL-8 or CXCL8) is a granulocytic chemokine with multiple roles within the tumor microenvironment (TME), such as recruiting immunosuppressive cells to the tumor, increasing tumor angiogenesis, and promoting epithelial-to-mesenchymal transition (EMT). All of these effects of CXCL8 on individual cell types can result in cascading alterations to the TME. The changes in the TME components such as the cancer-associated fibroblasts (CAFs), the immune cells, the extracellular matrix, the blood vessels, or the lymphatic vessels further influence tumor progression and therapeutic resistance. Emerging roles of the microbiome in tumorigenesis or tumor progression revealed the intricate interactions between inflammatory response, dysbiosis, metabolites, CXCL8, immune cells, and the TME. Studies have shown that CXCL8 directly contributes to TME remodeling, cancer plasticity, and the development of resistance to both chemotherapy and immunotherapy. Further, clinical data demonstrate that CXCL8 could be an easily measurable prognostic biomarker in patients receiving immune checkpoint inhibitors. The blockade of the CXCL8-CXCR1/2 axis alone or in combination with other immunotherapy will be a promising strategy to improve antitumor efficacy. Herein, we review recent advances focusing on identifying the mechanisms between TME components and the CXCL8-CXCR1/2 axis for novel immunotherapy strategies.

Overexpression of DOCK6 in oral squamous cell cancer promotes cellular migration and invasion and is associated with poor prognosis

OBJECTIVE

We aimed to identify the role of DOCK6 in oral squamous cell cancer (OSCC) in this study.

DESIGN

DOCK6 expression in OSCC was analyzed using TCGA and GEO datasets and was verified by quantitative real-time PCR, Western blotting, and immunohistochemistry. Statistical analyses were performed to evaluate the relationships between DOCK6 expression and the clinicopathological characteristics of OSCC patients. Wound healing and Transwell assays were performed to assess OSCC cell migration and invasion, respectively. STRING and GO analyses and gene set enrichment analysis were used to identify DOCK6-interacting proteins, their functions and their potential pathways.

RESULTS

DOCK6 was significantly upregulated at both the mRNA and protein levels in OSCC tissues (all P < 0.05). DOCK6 levels were positively correlated with age (P < 0.05), lymph node metastasis status (P < 0.001), clinical stage (P < 0.001), differentiation (P < 0.05), and poor clinical outcome (P < 0.05) in OSCC patients. Furthermore, univariate and multivariate analyses revealed that high DOCK6 expression (P < 0.01) and clinical stage III-IV (P < 0.05) might serve as independent prognostic factors for OSCC patients. Functionally, DOCK6 silencing significantly suppressed OSCC cell migration and invasion (all P < 0.05). Ten proteins that interact with DOCK6, more than ten functions related to cancer, and more than six pathways related to DOCK6 in OSCC were identified via bioinformatic methods.

CONCLUSION

DOCK6 is upregulated in OSCC, is associated with a poor prognosis in OSCC patients and increases OSCC cells migration and invasion. These findings suggest that DOCK6 may be a potential therapeutic target with prognostic implication in patients with OSCC.

Linc00467 promotes invasion and inhibits apoptosis of head and neck squamous cell carcinoma by regulating miR-1285-3p/TFAP2A

OBJECTIVE

To explore the invasion and apoptosis of head and neck squamous cell carcinoma (HNSCC) regulated by Linc00467 through the miR-1285-3p/TFAP2A axis.

METHODS

qRT-PCR was used to detect the expressions of Linc00467, miR-1285-3p, and TFAP2A in tissues and cells of HNSCC patients. The targeting relationships between Linc00467 and miR-1285-3p, miR-1285-3p, and TFAP2A were verified by dual-luciferase reporter assay. Transfection and grouping were carried out, after HNSCC cell lines were screened. Transwell assay and flow cytometry were used to test cell invasion and apoptosis, respectively.

RESULTS

Compared with normal tissues adjacent to the tumor, the expressions of Linc00467 and TFAP2A increased significantly in cancer tissues, while the expression of miR-1285-3p decreased (all P<0.05). Compared with the si-NC group, the invasion of the si-Linc00467 group decreased and the apoptosis rate increased (both P<0.05). In HNSCC cells, over-expression of Linc00467 promoted increased cell invasion and decreased apoptosis rate, which could be partially rescued by over-expression of miR-1285-3p (all P<0.05). Over-expression of miR-1285-3p caused decreased cell invasion and increased apoptosis rate, which was partially reversed by over-expression of TFAP2A (all P<0.05).

CONCLUSION

Linc00467 can be used as ceRNA to adsorb miR-1285-3p to regulate the expression of TFAP2A, promote invasion and inhibit apoptosis of HNSCC cells. Linc00467 inhibitors may become one of the targeted therapeutic drugs for HNSCC.

Interleukin-6 and Interleukin-8 Regulate STAT3 Activation Migration/Invasion and EMT in Chrysophanol-Treated Oral Cancer Cell Lines

The tumor microenvironment plays a critical role in the control of metastasis. The epithelial–mesenchymal transition (EMT) is strongly associated with tumor metastasis, and consists of several protein markers, including E-cadherin and vimentin. We discovered that chrysophanol causes oral cancer cell apoptosis and the inhibition of migration/invasion and EMT. However, the detailed mechanisms of chrysophanol and its role in oral cancer with respect to the tumor microenvironment remain unknown. In the clinic, proinflammatory cytokines, such as IL-6 and IL-8, exhibit a higher expression in patients with oral cancer. However, the effect of chrysophanol on the production of IL-6 and IL-8 is unknown. We evaluated the expression of IL-6 and IL-8 in human SAS and FaDu oral cancer cell lines in the presence or absence of chrysophanol. The migration and invasion abilities were also determined using a Boyden chamber assay. Our results showed that treatment with chrysophanol significantly decreased the expression of IL-6 and IL-8, as well as the invasion ability of oral cancer cells. Moreover, chrysophanol also attenuated the EMT by increasing the expression of E-cadherin and reducing the expression of vimentin. Mechanistically, chrysophanol inhibited IL-6- and IL-8-induced invasion and STAT3 phosphorylation. IL-6 and IL-8 promote EMT and cell invasion, which is potentially related to the STAT3 signaling pathway in oral cancer. These findings provide insight into new aspects of chrysophanol activity and may contribute to the development of new therapeutic strategies for oral cancer.

Chemokine-Cytokine Networks in the Head and Neck Tumor Microenvironment

Head and neck squamous cell carcinomas (HNSCCs) are aggressive diseases with a dismal patient prognosis. Despite significant advances in treatment modalities, the five-year survival rate in patients with HNSCC has improved marginally and therefore warrants a comprehensive understanding of the HNSCC biology. Alterations in the cellular and non-cellular components of the HNSCC tumor micro-environment (TME) play a critical role in regulating many hallmarks of cancer development including evasion of apoptosis, activation of invasion, metastasis, angiogenesis, response to therapy, immune escape mechanisms, deregulation of energetics, and therefore the development of an overall aggressive HNSCC phenotype. Cytokines and chemokines are small secretory proteins produced by neoplastic or stromal cells, controlling complex and dynamic cell-cell interactions in the TME to regulate many cancer hallmarks. This review summarizes the current understanding of the complex cytokine/chemokine networks in the HNSCC TME, their role in activating diverse signaling pathways and promoting tumor progression, metastasis, and therapeutic resistance development.

Small in Size, but Large in Action: microRNAs as Potential Modulators of PTEN in Breast and Lung Cancers

MicroRNAs (miRNAs) are well-known regulators of biological mechanisms with a small size of 19–24 nucleotides and a single-stranded structure. miRNA dysregulation occurs in cancer progression. miRNAs can function as tumor-suppressing or tumor-promoting factors in cancer via regulating molecular pathways. Breast and lung cancers are two malignant thoracic tumors in which the abnormal expression of miRNAs plays a significant role in their development. Phosphatase and tensin homolog (PTEN) is a tumor-suppressor factor that is capable of suppressing the growth, viability, and metastasis of cancer cells via downregulating phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling. PTEN downregulation occurs in lung and breast cancers to promote PI3K/Akt expression, leading to uncontrolled proliferation, metastasis, and their resistance to chemotherapy and radiotherapy. miRNAs as upstream mediators of PTEN can dually induce/inhibit PTEN signaling in affecting the malignant behavior of lung and breast cancer cells. Furthermore, long non-coding RNAs and circular RNAs can regulate the miRNA/PTEN axis in lung and breast cancer cells. It seems that anti-tumor compounds such as baicalein, propofol, and curcumin can induce PTEN upregulation by affecting miRNAs in suppressing breast and lung cancer progression. These topics are discussed in the current review with a focus on molecular pathways.