The Influence of Met Receptor Level on HGF-Induced Glycolytic Reprogramming in Head and Neck Squamous Cell Carcinoma

Unveiling the Role of HGF/c-Met Signaling in Non-Small Cell Lung Cancer Tumor Microenvironment

Non-small cell lung cancer (NSCLC) is characterized by several molecular alterations that contribute to its development and progression. These alterations include the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), human epidermal growth factor receptor 2 (HER2), and mesenchymal-epithelial transition factor (c-MET). Among these, the hepatocyte growth factor (HGF)/c-MET signaling pathway plays a crucial role in NSCLC. In spite of this, the involvement of the HGF/c-MET signaling axis in remodeling the tumor microenvironment (TME) remains relatively unexplored. This review explores the biological functions of the HGF/c-MET signaling pathway in both normal and cancerous cells, examining its multifaceted roles in the NSCLC tumor microenvironment, including tumor cell proliferation, migration and invasion, angiogenesis, and immune evasion. Furthermore, we summarize the current progress and clinical applications of MET-targeted therapies in NSCLC and discuss future research directions, such as the development of novel MET inhibitors and the potential of combination immunotherapy.

The MET Family of Receptor Tyrosine Kinases Promotes a Shift to Pro-Tumor Metabolism

The development and growth of cancer is fundamentally dependent on pro-tumor changes in metabolism. Cancer cells generally shift away from oxidative phosphorylation as the primary source of energy and rely more heavily on glycolysis. Receptor tyrosine kinases (RTKs) are a type of receptor that is implicated in this shift to pro-tumor metabolism. RTKs are important drivers of cancer growth and metastasis. One such family of RTKs is the MET family, which consists of MET and RON (MST1R). The overexpression of either MET or RON has been associated with worse cancer patient prognosis in a variety of tumor types. Both MET and RON signaling promote increased glycolysis by upregulating the expression of key glycolytic enzymes via increased MYC transcription factor activity. Additionally, both MET and RON signaling promote increased cholesterol biosynthesis downstream of glycolysis by upregulating the expression of SREBP2-induced cholesterol biosynthesis enzymes via CTTNB1. These changes in metabolism, driven by RTK activity, provide potential targets in limiting tumor growth and metastasis via pharmacological inhibition or modifications in diet. This review summarizes pro-tumor changes in metabolism driven by the MET family of RTKs. In doing so, we will offer our unique perspective on metabolic pathways that drive worse patient prognosis and provide suggestions for future study.

Differential Immune Checkpoint Protein Expression in HNSCC: The Role of HGF/MET Signaling

Although inhibitors targeting the PD1/PD-L1 immune checkpoint are showing comparably good outcomes, a significant percentage of head and neck squamous cell carcinoma (HNSCC) patients do not respond to treatment. Apart from using different treatment strategies, another possibility would be to target other immune checkpoints operating in these non-responding tumors. To obtain an overview of which checkpoint ligands are expressed on HNSCC tumor cells and if these ligands are affected by HGF/MET signaling, we used mRNA sequencing and antibody-based techniques for identifying checkpoint ligands in six HNSCC tumor cell lines. Furthermore, we compared our results to mRNA sequencing data. From the checkpoint ligands we investigated, VISTA was expressed the highest at the RNA level and was also the most ubiquitously expressed. PD-L2 and B7-H3 were expressed comparably lower and were not present in all cell lines to the same extent. B7-H4, however, was only detectable in the Detroit 562 cell line. Concerning the effect of HGF on the ligand levels, PD-L2 expression was enhanced with HGF stimulation, whereas other checkpoint ligand levels decreased with stimulation. B7-H4 levels in the Detroit 562 cell line drastically decreased with HGF stimulation. This is of interest because both the checkpoint ligand and the growth factor are reported to be connected to epithelial-mesenchymal transition in the literature.

Targeting the hedgehog pathway in MET mutation cancers and its effects on cells associated with cancer development

The mutation of MET plays a crucial role in the initiation of cancer, while the Hedgehog (Hh) pathway also plays a significant role in cell differentiation and the maintenance of tumor stem cells. Conventional chemotherapy drugs are primarily designed to target the majority of cell populations within tumors rather than tumor stem cells. Consequently, after a brief period of remission, tumors often relapse. Moreover, the exclusive targeting of tumor stemness cell disregards the potential for other tumor cells to regain stemness and acquire drug resistance. As a result, current drugs that solely target the HGF/c-MET axis and the Hh pathway demonstrate only moderate efficacy in specific types of cancer. Mounting evidence indicates that these two pathways not only play important roles in cancer but also exert significant influence on the development of resistance to single-target therapies through the secretion of their own ligands. In this comprehensive review, we analyze and compare the potential impact of the Hh pathway on the tumor microenvironment (TME) in HGF/c-MET-driven tumor models, as well as the interplay between different cell types. Additionally, we further substantiate the potential and necessity of dual-pathway combination therapy as a critical target in MET addicted cancer treatment. Video Abstract.

Targeting cellular metabolism in head and neck cancer precision medicine era: A promising strategy to overcome therapy resistance

Head and neck squamous cell carcinoma (HNSCC) is among the most prevalent cancer worldwide, with the most severe impact on quality of life of patients. Despite the development of multimodal therapeutic approaches, the clinical outcomes of HNSCC are still unsatisfactory, mainly caused by relatively low responsiveness to treatment and severe drug resistance. Metabolic reprogramming is currently considered to play a pivotal role in anticancer therapeutic resistance. This review aimed to define the specific metabolic programs and adaptations in HNSCC therapy resistance. An extensive literature review of HNSCC was conducted via the PubMed including metabolic reprogramming, chemo- or immune-therapy resistance. Glucose metabolism, fatty acid metabolism, and amino acid metabolism are closely related to the malignant biological characteristics of cancer, anti-tumor drug resistance, and adverse clinical results. For HNSCC, pyruvate, lactate and almost all lipid categories are related to the occurrence and maintenance of drug resistance, and targeting amino acid metabolism can prevent tumor development and enhance the response of drug-resistant tumors to anticancer therapy. This review will provide a better understanding of the altered metabolism in therapy resistance of HNSCC and promote the development of new therapeutic strategies against HNSCC, thereby contribute to a more efficacious precision medicine.

Cancer-associated fibroblasts: Mediators of head and neck tumor microenvironment remodeling

Cancer-associated fibroblasts (CAFs) are involved in critical aspects of head and neck squamous cell carcinoma (HNSCC) pathogenesis, such as the formation of a tumor-permissive extracellular matrix structure, angiogenesis, or immune and metabolic reprogramming of the tumor microenvironment (TME), with implications for metastasis and resistance to radiotherapy and chemotherapy. The pleiotropic effect of CAFs in TME is likely to reflect the heterogeneity and plasticity of their population, with context-dependent effects on carcinogenesis. The specific properties of CAFs provide many targetable molecules that could play an important role in the future therapy of HNSCC. In this review article, we will focus on the role of CAFs in the TME of HNSCC tumors. We will also discuss clinically relevant agents targeting CAFs, their signals, and signaling pathways, which are activated by CAFs in cancer cells, with the potential for repurposing for HNSCC therapy.

Prognostic utility of TME-associated genes in pancreatic cancer

Background: Pancreatic cancer (PC) is a deadly disease. The tumor microenvironment (TME) participates in PC oncogenesis. This study focuses on the assessment of the prognostic and treatment utility of TME-associated genes in PC. Methods: After obtaining the differentially expressed TME-related genes, univariate and multivariate Cox analyses and least absolute shrinkage and selection operator (LASSO) were performed to identify genes related to prognosis, and a risk model was established to evaluate risk scores, based on The Cancer Genome Atlas (TCGA) data set, and it was validated by external data sets from the Gene Expression Omnibus (GEO) and Clinical Proteomic Tumor Analysis Consortium (CPTAC). Multiomics analyses were adopted to explore the potential mechanisms, discover novel treatment targets, and assess the sensitivities of immunotherapy and chemotherapy. Results: Five TME-associated genes, namely, FERMT1, CARD9, IL20RB, MET, and MMP3, were identified and a risk score formula constructed. Next, their mRNA expressions were verified in cancer and normal pancreatic cells. Multiple algorithms confirmed that the risk model displayed a reliable ability of prognosis prediction and was an independent prognostic factor, indicating that high-risk patients had poor outcomes. Immunocyte infiltration, gene set enrichment analysis (GSEA), and single-cell analysis all showed a strong relationship between immune mechanism and low-risk samples. The risk score could predict the sensitivity of immunotherapy and some chemotherapy regimens, which included oxaliplatin and irinotecan. Various latent treatment targets (LAG3, TIGIT, and ARID1A) were addressed by mutation landscape based on the risk model. Conclusion: The risk model based on TME-related genes can reflect the prognosis of PC patients and functions as a novel set of biomarkers for PC therapy.

FSCN1 promotes proliferation, invasion and glycolysis via the IRF4/AKT signaling pathway in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a disease with increasing incidence worldwide that leads to deformity and death. In OSCC, fascin actin-bundling protein 1 (FSCN1) is an oncogene involved in the tumorigenesis process. However, the functions and potential mechanisms of FSCN1 in the OSCC tumorigenesis process have not been reported thus far.

METHODS

We used qRT‒PCR to detect the expression of FSCN1 in 40 paired OSCC tumor tissues (tumor) and neighboring noncancerous tissues. The role of FSCN1 was also assessed in vitro through colony formation, CCK-8, and transwell assays. Moreover, glucose consumption was detected. Western blotting was used to confirm the interaction of FSCN1, IRF4 and AKT.

RESULTS

FSCN1 was remarkably overexpressed in OSCC tissues and cell lines compared to corresponding controls. In addition, colony formation, CCK-8, and transwell assays revealed a notable reduction in OSCC growth and invasion when FSCN1 was silenced. FSCN1 silencing remarkably suppressed OSCC glycolysis. Mechanistic studies showed that FSCN1 achieves its function partially by activating interferon regulatory factor 4 (IRF4) and the AKT pathway in OSCC.

CONCLUSION

In conclusion, our study investigated the functions and mechanisms of the FSCN1/IRF4/AKT pathway in OSCC progression. In OSCC, FSCN1 is likely to be a biomarker and therapeutic target.

c-Met Signaling as a Therapeutic Target in Head and Neck Cancer

ABSTRACT

Despite a dearth of activating driver mutations in head and neck squamous cell carcinoma (HNSCC), aberrant activation of the oncogenes, epidermal growth factor receptor (EGFR), and c-Met is near-universal in human papillomavirus (HPV)-negative disease. Although EGFR activation drove the successful development of the anti-EGFR monoclonal antibody cetuximab in HNSCC, no c-Met-targeting therapy has gained regulatory approval. Inhibition of the c-Met pathway may subvert oncogenesis within the tumor-intrinsic compartment, blocking tumoral proliferation, invasion, migration, and metastasis, or the tumor-extrinsic compartment, modulating the immunosuppressive tumor microenvironment. This review discusses the rationale and current drug development strategies for targeting c-Met or its exclusive ligand hepatocyte growth factor (HGF) in HNSCC.

Molecular mechanism(s) of regulation(s) of c-MET/HGF signaling in head and neck cancer

Head and neck cancer is the sixth most common cancer across the globe. This is generally associated with tobacco and alcohol consumption. Cancer in the pharynx majorly arises through human papillomavirus (HPV) infection, thus classifying head and neck squamous cell carcinoma (HNSCC) into HPV-positive and HPV-negative HNSCCs. Aberrant, mesenchymal-epithelial transition factor (c-MET) signal transduction favors HNSCC progression by stimulating proliferation, motility, invasiveness, morphogenesis, and angiogenesis. c-MET upregulation can be found in the majority of head and neck squamous cell carcinomas. c-MET pathway acts on several downstream effectors including phospholipase C gamma (PLCγ), cellular Src kinase (c-Src), phosphotidylinsitol-3-OH kinase (PI3K), alpha serine/threonine-protein kinase (Akt), mitogen-activated protein kinase (MAPK), and wingless-related integration site (Wnt) pathways. c-MET also establishes a crosstalk pathway with epidermal growth factor receptor (EGFR) and contributes towards chemoresistance in HNSCC. In recent years, the signaling communications of c-MET/HGF in metabolic dysregulation, tumor-microenvironment and immune modulation in HNSCC have emerged. Several clinical trials have been established against c-MET/ hepatocyte growth factor (HGF) signaling network to bring up targeted and effective therapeutic strategies against HNSCC. In this review, we discuss the molecular mechanism(s) and current understanding of c-MET/HGF signaling and its effect on HNSCC.

Graphical abstract

PKM2 Modulation in Head and Neck Squamous Cell Carcinoma

The enzyme pyruvate kinase M2 (PKM2) plays a major role in the switch of tumor cells from oxidative phosphorylation to aerobic glycolysis, one of the hallmarks of cancer. Different allosteric inhibitors or activators and several posttranslational modifications regulate its activity. Head and neck squamous cell carcinoma (HNSCC) is a common disease with a high rate of recurrence. To find out more about PKM2 and its modulation in HNSCC, we examined a panel of HNSCC cells using real-time cell metabolic analysis and Western blotting with an emphasis on phosphorylation variant Tyr105 and two reagents known to impair PKM2 activity. Our results show that in HNSCC, PKM2 is commonly phosphorylated at Tyrosine 105. Its levels depended on tyrosine kinase activity, emphasizing the importance of growth factors such as EGF (epidermal growth factor) on HNSCC metabolism. Furthermore, its correlation with the expression of CD44 indicates a role in cancer stemness. Cells generally reacted with higher glycolysis to PKM2 activator DASA-58 and lower glycolysis to PKM2 inhibitor Compound 3k, but some were more susceptible to activation and others to inhibition. Our findings emphasize the need to further investigate the role of PKM2 in HNSCC, as it could aid understanding and treatment of the disease.

The glutaminase inhibitor telaglenastat enhances the antitumor activity of signal transduction inhibitors everolimus and cabozantinib in models of renal cell carcinoma

Dysregulated metabolism is a hallmark of cancer that manifests through alterations in bioenergetic and biosynthetic pathways to enable tumor cell proliferation and survival. Tumor cells exhibit high rates of glycolysis, a phenomenon known as the Warburg effect, and an increase in glutamine consumption to support the tricarboxylic acid (TCA) cycle. Renal cell carcinoma (RCC) tumors express high levels of glutaminase (GLS), the enzyme required for the first step in metabolic conversion of glutamine to glutamate and the entry of glutamine into the TCA cycle. We found that RCC cells are highly dependent on glutamine for proliferation, and this dependence strongly correlated with sensitivity to telaglenstat (CB-839), an investigational, first-in-class, selective, orally bioavailable GLS inhibitor. Metabolic profiling of RCC cell lines treated with telaglenastat revealed a decrease in glutamine consumption, which was concomitant with a decrease in the production of glutamate and other glutamine-derived metabolites, consistent with GLS inhibition. Treatment of RCC cells with signal transduction inhibitors everolimus (mTOR inhibitor) or cabozantinib (VEGFR/MET/AXL inhibitor) in combination with telaglenastat resulted in decreased consumption of both glucose and glutamine and synergistic anti-proliferative effects. Treatment of mice bearing Caki-1 RCC xenograft tumors with cabozantinib plus telaglenastat resulted in reduced tumor growth compared to either agent alone. Enhanced anti-tumor activity was also observed with the combination of everolimus plus telaglenastat. Collectively, our results demonstrate potent, synergistic, anti-tumor activity of telaglenastat plus signal transduction inhibitors cabozantinib or everolimus via a mechanism involving dual inhibition of glucose and glutamine consumption.

Protein Phosphatase 2A as a Therapeutic Target in Small Cell Lung Cancer

Protein phosphatase 2A (PP2A), a serine/threonine phosphatase involved in the regulation of apoptosis, proliferation, and DNA-damage response, is overexpressed in many cancers, including small cell lung cancer (SCLC). Here we report that LB100, a small molecule inhibitor of PP2A, when combined with platinum-based chemotherapy, synergistically elicited an antitumor response both in vitro and in vivo with no apparent toxicity. Using inductively coupled plasma mass spectrometry, we determined quantitatively that sensitization via LB100 was mediated by increased uptake of carboplatin in SCLC cells. Treatment with LB100 alone or in combination resulted in inhibition of cell viability in two-dimensional culture and three-dimensional spheroid models of SCLC, reduced glucose uptake, and attenuated mitochondrial and glycolytic ATP production. Combining LB100 with atezolizumab increased the capacity of T cells to infiltrate and kill tumor spheroids, and combining LB100 with carboplatin caused hyperphosphorylation of the DNA repair marker γH2AX and enhanced apoptosis while attenuating MET signaling and invasion through an endothelial cell monolayer. Taken together, these data highlight the translational potential of inhibiting PP2A with LB100 in combination with platinum-based chemotherapy and immunotherapy in SCLC.

Knockout of Hepatocyte Growth Factor by CRISPR/Cas9 System Induces Apoptosis in Hepatocellular Carcinoma Cells

Background: CRISPR/Cas9 system is a prokaryotic adaptive immune response system that uses noncoding RNAs to guide the Cas9 nuclease to induce site-specific DNA cleavage. Hepatocyte growth factor (HGF) is a well-known growth factor that plays a crucial role in cell growth and organ development. According to recent studies, it has been reported that HGF promoted growth of hepatocellular carcinoma (HCC) cells. Here, we investigated the apoptotic effects in HCC cells. Methods: Crispr-HGF plasmid was constructed using GeneArt CRISPR Nuclease Vector. pMex-HGF plasmid that targets HGF overexpressing gene were designed with pMex-neo plasmid. We performed real time-polymerase chain reaction to measure the expression of HGF mRNA. We performed cell counting assay and colony formation assay to evaluate cell proliferation. We also carried out migration assay and invasion assay to reveal the inhibitory effects of Crispr-HGF in HCC cells. Furthermore, we performed cell cycle analysis to detect transfection of Crispr-HGF induced cell cycle arrest. Collectively, we performed annexin V/PI staining assay and Western blot assay. Results: In Crispr-HGF-transfected group, the mRNA expression levels of HGF were markedly downregulated compared to pMex-HGF-transfected group. Moreover, Crispr-HGF inhibited cell viability in HCC cells. We detected that wound area and invaded cells were suppressed in Crispr-HGF-transfected cells. The results showed that transfection of Crispr-HGF induced cell cycle arrest and apoptosis in HCC cells. Expression of the phosphorylation of mitogen activated protein kinases and c-Met protein was regulated in Crispr-HGF-transfected group. Interestingly, we found that the expression of HGF protein in conditioned media significantly decreased in Crispr-HGF-transfected group. Conclusions: Taken together, we found that inhibition of HGF through transfection of Crispr-HGF suppressed cell proliferation and induced apoptotic effects in HCC Huh7 and Hep3B cells.

High glucose induced c-Met activation promotes aggressive phenotype and regulates expression of glucose metabolism genes in HCC cells

Hepatocellular carcinoma (HCC) is strongly associated with metabolic dysregulations/deregulations and hyperglycemia is a common metabolic disturbance in metabolic diseases. Hyperglycemia is defined to promote epithelial to mesenchymal transition (EMT) of cancer cells in various cancers but its molecular contribution to HCC progression and aggressiveness is relatively unclear. In this study, we analyzed the molecular mechanisms behind the hyperglycemia-induced EMT in HCC cell lines. Here, we report that high glucose promotes EMT through activating c-Met receptor tyrosine kinase via promoting its ligand-independent homodimerization. c-Met activation is critical for high glucose induced acquisition of mesenchymal phenotype, survival under high glucose stress and reprogramming of cellular metabolism by modulating glucose metabolism gene expression to promote aggressiveness in HCC cells. The crucial role of c-Met in high glucose induced EMT and aggressiveness may be the potential link between metabolic syndrome-related hepatocarcinogenesis and/or HCC progression. Considering c-Met inhibition in hyperglycemic patients would be an important complementary strategy for therapy that favors sensitization of HCC cells to therapeutics.

In vivo detection of distal tumor glycolytic flux stimulated by hepatic ablation in a breast cancer model using hyperpolarized 13C MRI

PURPOSE

Hepatic thermal ablation therapy can result in c-Met-mediated off-target stimulation of distal tumor growth. The purpose of this study was to determine if a similar effect on tumor metabolism could be detected in vivo with hyperpolarized ¹³C MRI.

MATERIALS AND METHODS

In this prospective study, female Fisher rats (n = 28, 120-150 g) were implanted with R3230 rat breast adenocarcinoma cells and assigned to either: sham surgery, hepatic radiofrequency ablation (RFA), or hepatic RFA + adjuvant c-Met inhibition with PHA-665752 (RFA + PHA). PHA-665752 was administered at 0.83 mg/kg at 24 h post-RFA. Tumor growth was measured daily. MRI was performed 24 h before and 72 h after treatment on 14 rats, and the conversion of ¹³C-pyruvate into ¹³C-lactate within each tumor was quantified as lactate:pyruvate ratio (LPR). Comparisons of tumor growth and LPR were performed using paired and unpaired t-tests.

RESULTS

Hepatic RFA alone resulted in increased growth of the distant tumor compared to sham treatment (0.50 ± 0.13 mm/day versus 0.11 ± 0.07 mm/day; p < 0.001), whereas RFA + PHA (0.06 ± 0.13 mm/day) resulted in no significant change from sham treatment (p = 0.28). A significant increase in LPR was seen following hepatic RFA (+0.016 ± 0.010, p = 0.02), while LPR was unchanged for sham treatment (-0.048 ± 0.051, p = 0.10) or RFA + PHA (0.003 ± 0.041, p = 0.90).

CONCLUSION

In vivo hyperpolarized ¹³C MRI can detect hepatic RFA-induced increase in lactate flux within a distant R3230 tumor, which correlates with increased tumor growth. Adjuvant inhibition of c-Met suppresses these off-target effects, supporting a role for the HGF/c-Met signaling axis in these tumorigenic responses.

Molecular phenotypes of circulating tumor cells and efficacy of nivolumab treatment in patients with head and neck squamous cell carcinoma

The emergence of immune checkpoint inhibitors (ICIs) has revolutionized the treatment of recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). Biomarkers of the therapeutic efficacy of ICIs have been extensively investigated. In this study, we aimed to analyze whether molecular phenotypes of circulating tumor cells (CTCs) are associated with treatment responses and clinical outcomes in patients with R/M HNSCC treated with nivolumab. Peripheral blood samples were collected before treatment initiation and after four infusions of nivolumab. CTCs isolated by depletion of CD45-positive cells were analyzed to determine the expression of EPCAM, MET, KRT19, and EGFR using real-time quantitative polymerase chain reaction. CTC-positive samples were analyzed to determine the expression of PIK3CA, CCND1, SNAI1, VIM, ZEB2, CD44, NANOG, ALDH1A1, CD47, CD274, and PDCD1LG2. Of 30 patients treated with nivolumab, 28 (93.3%) were positive for CTCs. In 20 CTC-positive patients, molecular alterations in CTCs before and after nivolumab treatment were investigated. Patients with MET-positive CTCs had significantly shorter overall survival than those with MET-negative CTCs (p = 0.027). The expression level of CCND1 in CTCs of disease-controlled patients was significantly higher than that of disease-progressed patients (p = 0.034). In disease-controlled patients, the expression level of CCND1 in CTCs significantly decreased after nivolumab treatment (p = 0.043). The NANOG expression in CTCs was significantly increased in disease-controlled patients after nivolumab treatment (p = 0.036). Our findings suggest that the molecular profiling of CTCs is a promising tool to predict the treatment efficacy of nivolumab.

HGF-Induced PD-L1 Expression in Head and Neck Cancer: Preclinical and Clinical Findings

Head and neck squamous cell carcinoma (HNSCC) is a widespread disease with a low survival rate and a high risk of recurrence. Nowadays, immune checkpoint inhibitor (ICI) treatment is approved for HNSCC as a first-line treatment in recurrent and metastatic disease. ICI treatment yields a clear survival benefit, but overall response rates are still unsatisfactory. As shown in different cancer models, hepatocyte growth factor/mesenchymal–epithelial transition (HGF/Met) signaling contributes to an immunosuppressive microenvironment. Therefore, we investigated the relationship between HGF and programmed cell death protein 1 (PD-L1) expression in HNSCC cell lines. The preclinical data show a robust PD-L1 induction upon HGF stimulation. Further analysis revealed that the HGF-mediated upregulation of PD-L1 is MAP kinase-dependent. We then hypothesized that serum levels of HGF and soluble programmed cell death protein 1 (sPD-L1) could be potential markers of ICI treatment failure. Thus, we determined serum levels of these proteins in 20 HNSCC patients before ICI treatment and correlated them with treatment outcomes. Importantly, the clinical data showed a positive correlation of both serum proteins (HGF and sPD-L1) in HNSCC patient’s sera. Moreover, the serum concentration of sPD-L1 was significantly higher in ICI non-responsive patients. Our findings indicate a potential role for sPD-L1 as a prognostic marker for ICI treatment in HNSCC.

Editorial for the Special Issue "New Strategies in Cancer Pharmacotherapy: Development of Hormonal Antineoplastic Drugs, Cytotoxic Drugs and Targeted Therapies"

The Special Issue entitled "New Strategies in Cancer Pharmacotherapy: Development of Hormonal Antineoplastic Drugs, Cytotoxic Drugs and Targeted Therapies" was conceived with the idea of compiling information on the latest advances in the treatment of both hormone-dependent and hormone-independent cancers [...].

Tanshinone IIA inhibits oral squamous cell carcinoma via reducing Akt-c-Myc signaling-mediated aerobic glycolysis

Aerobic glycolysis is one of the hallmarks of human cancer cells. Overexpression of hexokinase 2 (HK2) plays a crucial role in the maintaining of unlimited tumor cell growth. In the present study, we found that the oral squamous cell carcinoma (OSCC) cells exhibited an aerobic glycolysis phenotype. Moreover, HK2 is highly expressed in OSCC patient derived-tissues and cell lines. Depletion of HK2 inhibited OSCC cell growth in vitro and in vivo. With a natural product screening, we identified Tanshinone IIA (Tan IIA) as a potential anti-tumor compound for OSCC through suppressing HK2-mediated glycolysis. Tan IIA decreased glucose consumption, lactate production, and promoted intrinsic apoptosis in OSCC cells. The mechanism study revealed that Tan IIA inhibited the Akt-c-Myc signaling and promoted E3 ligase FBW7-mediated c-Myc ubiquitination and degradation, which eventually reduced HK2 expression at the transcriptional level. In summary, these results indicate that targeting HK2-mediated aerobic glycolysis is a promising anti-tumor strategy for OSCC treatment.