The role of transforming growth factor-beta in immune suppression and chronic inflammation of squamous cell carcinomas

MHC class I upregulation contributes to the therapeutic response to radiotherapy in combination with anti-PD-L1/anti-TGF-β in squamous cell carcinomas with enhanced CD8 T cell memory-driven response

Radiation therapy (RT), a mainstay treatment for head and neck squamous cell carcinoma (HNSCC), kills cancer cells and modulates the tumor immune microenvironment. We sought to assess the effect of RT in combination with PD-L1/TGF-β dual blockade in squamous cell carcinomas (SCC) and analyze the underlying mechanisms. We transplanted mouse SCC cells derived from keratin-15 (K15) stem cells harboring KrasG12D/Smad4-/- mutations into syngeneic recipients and irradiated tumors followed by PD-L1/TGF-β dual blockade. We identified a responder line and a non-responder line to this combination therapy. Responder hosts eradicated SCCs by the combined therapy and rejected re-transplanted SCC cells 6 months post tumor eradication, which correlated with clonotype expansions of splenic CD8 T cells and effector memory gene expression identified by single cell sequencing of TCR and transcriptomes, respectively. Mechanistically, RT upregulated MHC-I (major histocompatibility complex I) and its transcriptional regulators including NLRC5, in SCCs of the responders but not non-responders. These data are consistent with the TCGA HNSCC database in which NLRC5 correlated to MHC-I genes and CD8 T cell gene expression. Functional contribution of MHC-I to PD-L1/TGF-β blockade response was confirmed by knocking out beta-2-microglobulin in responder cells that attenuated the response to the same therapy. Thus, the therapeutic effectiveness appeared to largely depend on cancer-cell MHC-I expression, triggering CD8 T cell effector memory-driven responses against tumor cell antigens. Identifying the differential RT response to MHC-I induction may serve as a predictive marker for stratifying patients that are most likely to benefit from this combination therapy.

Growth factor-functionalized titanium implants for enhanced bone regeneration: A review

Titanium and titanium alloys are widely favored materials for orthopedic implants due to their exceptional mechanical properties and biological inertness. The additional benefit of sustained local release of bioactive substances further promotes bone tissue formation, thereby augmenting the osseointegration capacity of titanium implants and attracting increasing attention in bone tissue engineering. Among these bioactive substances, growth factors have shown remarkable osteogenic and angiogenic induction capabilities. Consequently, researchers have developed various physical, chemical, and biological loading techniques to incorporate growth factors into titanium implants, ensuring controlled release kinetics. In contrast to conventional treatment modalities, the localized release of growth factors from functionalized titanium implants not only enhances osseointegration but also reduces the risk of complications. This review provides a comprehensive examination of the types and mechanisms of growth factors, along with a detailed exploration of the methodologies used to load growth factors onto the surface of titanium implants. Moreover, it highlights recent advancements in the application of growth factors to the surface of titanium implants (Scheme 1). Finally, the review discusses current limitations and future prospects for growth factor-functionalized titanium implants. In summary, this paper presents cutting-edge design strategies aimed at enhancing the bone regenerative capacity of growth factor-functionalized titanium implants-a significant advancement in the field of enhanced bone regeneration.

Exploring NK-Cell molecules that impact the immune response and microenvironment in head and neck squamous cell carcinoma

NK cells play a role in various cancers, but their role in head and neck squamous cell carcinoma (HNSCC) still needs to be explored. All public data are obtained from the Cancer Genome Atlas Program (TCGA) database. All analysis was performed using specific packages in R software. In our study, we quantified the immune microenvironment of HNSCC through multiple algorithms. Next, we identified NK cell-associated genes by quantifying NK cells, including SSNA1, TRIR, PAXX, DPP7, WDR34, EZR, PHLDA1 and ELOVL1. Then, we explored the single-cell expression pattern of these genes in the HNSCC microenvironment. Univariate Cox regression analysis indicated that the EZR, PHLDA1 and ELOVL1 were related to the prognosis of HNSCC patients. Following this, we selected EZR for further analysis. Our results showed that the patients with high EZR expression might have a poor prognosis and worse clinical features. Biological enrichment analysis showed that EZR is associated with many oncogenic pathways and a higher tumour stemness index. Meanwhile, we found that EZR can remodel the immune microenvironment of HNSCC. Moreover, we noticed that EZR could affect the immunotherapy and specific drug sensitivity, making it an underlying clinical target. In summary, our results can improve the understanding of NK cell in HNSCC. Meanwhile, we identified EZR as the underlying clinical target of HNSCC.

Menstrual blood-derived endometrial stem cells inhibit neuroinflammation by regulating microglia through the TLR4/MyD88/NLRP3/Casp1 pathway

Neuroinflammation is a common response in various neurological disorders. Mesenchymal stem cell-based treatment has become a promising therapy for neuroinflammation-associated diseases. However, the effects of mesenchymal stem cells are controversial, and the underlying mechanism is incompletely understood. In the present study, menstrual blood-derived endometrial stem cells were intravenously transplanted into a mouse model of neuroinflammation established by peripheral injection of lipopolysaccharide. Microglial cells challenged with lipopolysaccharide were cultured with conditioned medium from endometrial stem cells. The levels of cytokines were detected by enzyme-linked immunosorbent assay. Cell proliferation and death were detected by Cell Counting Kit 8 and flow cytometry, respectively. The expression levels of Toll-like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (MyD88), NLR family pyrin domain containing 3 (NLRP3) and caspase 1 (Casp1) were evaluated by western blotting. The results showed that intravenous transplantation of endometrial stem cells downregulated proinflammatory factors and upregulated anti-inflammatory factors in the brain of mice with neuroinflammation. Conditioned medium suppressed the inflammatory reaction and hyperactivation of microglial cells and protected microglial cells from cell death induced by lipopolysaccharide in vitro. The expression of TLR4, MyD88, NLRP3 and Casp1 in the brain of mice with neuroinflammation and in lipopolysaccharide-stimulated microglial cells was downregulated by endometrial stem cells and conditioned medium, respectively. These data suggested that menstrual blood-derived endometrial stem cells may suppress neuroinflammatory reactions partially by regulating microglia through the TLR4/MyD88/NLRP3/Casp1 signalling pathway. Our findings may be very useful for the development of an alternative stem cell-based therapy for neuroinflammation-associated disorders.

Advanced Squamous Cell Carcinoma Developed on Chronic Hidradenitis Suppurativa, Successfully Treated with Cemiplimab: A Case Report

Hidradenitis suppurativa (HS) is an inflammatory skin disease showing a chronic-remitting course. It has been rarely reported that long-term inflammation in HS could lead to serious complications like cutaneous squamous cell carcinoma. Cemiplimab is a fully human antibody immunotherapy that inhibits programmed cell death protein-1, approved for the treatment of locally advanced squamous cell carcinoma, or metastatic squamous cell carcinoma, in patients not eligible for curative surgery or radiotherapy. Herein, we report the case of a 56-year-old patient developing an invasive SCC on longstanding and unresponsive HS lesions successfully treated with cemiplimab.

Transforming Growth Factor-β1 in Cancer Immunology: Opportunities for Immunotherapy

Transforming growth factor-beta1 (TGF-β) regulates a plethora of cell-intrinsic processes that modulate tumor progression in a context-dependent manner. Thus, although TGF-β acts as a tumor suppressor in the early stages of tumorigenesis, in late stages, this factor promotes tumor progression and metastasis. In addition, TGF-β also impinges on the tumor microenvironment by modulating the immune system. In this aspect, TGF-β exhibits a potent immunosuppressive effect, which allows both cancer cells to escape from immune surveillance and confers resistance to immunotherapy. While TGF-β inhibits the activation and antitumoral functions of T-cell lymphocytes, dendritic cells, and natural killer cells, it promotes the generation of T-regulatory cells and myeloid-derived suppressor cells, which hinder antitumoral T-cell activities. Moreover, TGF-β promotes tumor-associated macrophages and neutrophils polarization from M1 into M2 and N1 to N2, respectively. Altogether, these effects contribute to the generation of an immunosuppressive tumor microenvironment and support tumor promotion. This review aims to analyze the relevant evidence on the complex role of TGF-β in cancer immunology, the current outcomes of combined immunotherapies, and the anti-TGF-β therapies that may improve the success of current and new oncotherapies.

Construction of the prognostic signature of alternative splicing revealed the prognostic predictor and immune microenvironment in head and neck squamous cell carcinoma

Background: Head and neck squamous cell carcinoma (HNSC) is a prevalent and heterogeneous malignancy with poor prognosis and high mortality rates. There is significant evidence of alternative splicing (AS) contributing to tumor development, suggesting its potential in predicting prognosis and therapeutic efficacy. This study aims to establish an AS-based prognostic signature in HNSC patients.

Methods: The expression profiles and clinical information of 486 HNSC patients were downloaded from the TCGA database, and the AS data were downloaded from the TCGA SpliceSeq database. The survival-associated AS events were identified by conducting a Cox regression analysis and utilized to develop a prognostic signature by fitting into a LASSO-regularized Cox regression model. Survival analysis, univariate and multivariate Cox regression analysis, and receiver operating characteristic (ROC) curve analysis were performed to evaluate the signature and an independent cohort was used for validation. The immune cell function and infiltration were analyzed by CIBERSORT and the ssGSEA algorithm.

Results: Univariate Cox regression analysis identified 2726 survival-associated AS events from 1714 genes. The correlation network reported DDX39B, PRPF39, and ARGLU1 as key splicing factors (SF) regulating these AS events. Eight survival-associated AS events were selected and validated by LASSO regression to develop a prognostic signature. It was confirmed that this signature could predict HNSC outcomes independent of other variables via multivariate Cox regression analysis. The risk score AUC was more than 0.75 for 3 years, highlighting the signature’s prediction capability. Immune infiltration analysis reported different immune cell distributions between the two risk groups. The immune cell content was higher in the high-risk group than in the low-risk group. The correlation analysis revealed a significant correlation between risk score, immune cell subsets, and immune checkpoint expression.

Conclusion: The prognostic signature developed from survival-associated AS events could predict the prognosis of HNSC patients and their clinical response to immunotherapy. However, this signature requires further research and validation in larger cohort studies.

Comparative Analysis of Mutation Status and Immune Landscape for Squamous Cell Carcinomas at Different Anatomical sites

Objective

It has been controversial whether tumor mutation burden (TMB) affects the prognosis and the efficacy of immunotherapy in different tumor types. We provided a comprehensive analysis of mutation status and immune landscape of squamous cell carcinomas (SCCs) from four sites in order to investigate the relationship of TMB with prognosis and immune cell infiltration in different SCCs.

Methods

The transcriptome profiles and somatic mutation data of SCCs downloaded from the Cancer Genome Atlas (the Cancer Genome Atlas) database were analyzed and visualized. Then, TMB was calculated to analyze its correlations with prognosis and clinical features. Differentially expressed genes (DEGs) between the high and low TMB groups were screened for functional enrichment analysis. CIBERSORT algorithm was used to compare differences of immune cell infiltration between two groups in different SCCs. In addition, immune DEGs associated with prognosis were identified and risk prediction model was constructed via Cox regression analysis.

Results

Missense mutation was the most dominant mutation type in SCCs. The difference was that the top10 mutated genes varied widely among different SCCs. High TMB group had better prognosis in lung squamous cell carcinoma (LUSC) and cervical squamous cell carcinoma (CESC), while the result was reverse in head and neck squamous cell carcinoma (HNSCC) and esophageal squamous cell carcinoma (ESCC). In addition, patients with older age, smoking history, earlier pathological stage and no lymphatic invasion had higher TMB. The identified DEGs were mainly enriched in the regulation of immune system, muscular system and the activity of epidermal cells. The proportions of CD8+T cells, CD4+ memory T cells, follicular helper T cells, macrophages were distinct between two groups. The prognosis-related hub genes (CHGB, INHBA, LCN1 and VEGFC) screened were associated with poor prognosis.

Conclusion

This study reveals the mutation status and immune cell infiltration of SCCs at different anatomical sites. TMB is closely related to the prognosis of SCCs, and its effects on prognosis are diverse in different SCCs, which might result from the situation of immune cell infiltration. These findings contribute to the exploration of biomarkers for predicting the efficacy of immunotherapy in SCCs and providing innovative insights for accurate application of immunotherapy.

The Role of Immune Modulatory Cytokines in the Tumor Microenvironments of Head and Neck Squamous Cell Carcinomas

Simple Summary

Malignant phenotypes of head and neck squamous cell carcinomas (HNSCCs) are regulated by the pro- and anti-tumoral activities of immune modulatory cytokines associated with tumor microenvironments (TMEs). We first present the immune modulatory effects of pro-inflammatory cytokines, pro- and anti- (pro-/anti-) inflammatory cytokines, and anti-inflammatory cytokines upon HNSCC phenotypes. We then report our evaluation of the functions of cytokines and chemokines that mediate the crosstalk between tumors and stromal cells, including cancer-associated fibroblasts (CAFs), myeloid-derived suppressor cells (MDSCs), plasmacytoid dendritic cells (pDCs), and tumor-associated macrophages (TAMs). In HNSCCs, the status of lymph node metastasis is an important hallmark of a worse prognosis. Several chemokines mediate lymph node metastases in HNSCC patients. There are therapeutic approaches, using antitumoral cytokines or immunotherapies, that target cytokines, chemokines, or signal molecules essential for the immune evasion of HNSCCs. Finally, modulation by human papilloma virus (HPV) infection in HNSCC phenotypes and the prognostic significance of serum cytokine levels in HNSCC patients are discussed.

Abstract

HNSCCs are the major progressive malignancy of the upper digestive and respiratory organs. Malignant phenotypes of HNSCCs are regulated by the pro- and anti-tumoral activities of the immune modulatory cytokines associated with TMEs, i.e., a representative pro-inflammatory cytokine, interferon (IFN)-γ, plays a role as an anti-tumor regulator against HNSCCs; however, IFN-γ also drives programmed death-ligand (PD-L) 1 expression to promote cancer stem cells. Interleukin (IL)-2 promotes the cytotoxic activity of T cells and natural killer cells; however, endogenous IL-2 can promote regulatory T cells (Tregs), resulting in the protection of HNSCCs. In this report, we first classified and mentioned the immune modulatory aspects of pro-inflammatory cytokines, pro-/anti-inflammatory cytokines, and anti-inflammatory cytokines upon HNSCC phenotypes. In the TME of HNSCCs, pro-tumoral immune modulation is mediated by stromal cells, including CAFs, MDSCs, pDCs, and TAMs. Therefore, we evaluated the functions of cytokines and chemokines that mediate the crosstalk between tumor cells and stromal cells. In HNSCCs, the status of lymph node metastasis is an important hallmark of a worse prognosis. We therefore evaluated the possibility of chemokines mediating lymph node metastases in HNSCC patients. We also mention therapeutic approaches using anti-tumoral cytokines or immunotherapies that target cytokines, chemokines, or signal molecules essential for the immune evasion of HNSCCs. We finally discuss modulation by HPV infection upon HNSCC phenotypes, as well as the prognostic significance of serum cytokine levels in HNSCC patients.

Dual Role of p73 in Cancer Microenvironment and DNA Damage Response

Understanding the mechanisms that regulate cancer progression is pivotal for the development of new therapies. Although p53 is mutated in half of human cancers, its family member p73 is not. At the same time, isoforms of p73 are often overexpressed in cancers and p73 can overtake many p53 functions to kill abnormal cells. According to the latest studies, while p73 represses epithelial–mesenchymal transition and metastasis, it can also promote tumour growth by modulating crosstalk between cancer and immune cells in the tumor microenvironment, M2 macrophage polarisation, Th2 T-cell differentiation, and angiogenesis. Thus, p73 likely plays a dual role as a tumor suppressor by regulating apoptosis in response to genotoxic stress or as an oncoprotein by promoting the immunosuppressive environment and immune cell differentiation.

Distinct immune microenvironment profiles of therapeutic responders emerge in combined TGFβ/PD-L1 blockade-treated squamous cell carcinoma

Transforming growth factor beta (TGFβ) and programmed death-ligand 1 (PD-L1) are often overproduced in refractory squamous cell carcinoma (SCC). We examined spatial patterns of PD-L1⁺ cells in mouse and human SCCs and found that PD-L1 was primarily expressed on infiltrating leukocytes. Although combined TGFβ and PD-L1 blockade are undergoing cancer clinical trials, there are no predictive markers for therapeutic responders. To address this, we used both a small molecule TGFβ inhibitor in combination with anti-PD-L1 and a bifunctional fusion protein targeting both TGFβ and PD-L1 to treat mouse SCCs and found TGFβ inhibition enhanced PD-L1 blockade-induced tumor eradication in multiple tumor models. Furthermore, we identified distinct cell populations of responders and non-responders to bintrafusp alfa, with responders showing a shift toward a more immune-permissive microenvironment. The cellular and molecular signatures of responders versus non-responders to combined TGFβ and PD-L1 blockade provide important insights into future personalized immunotherapy in SCC.

Strait et al describe distinct immune microenvironment profiles of responders versus non-responders to combined TGF-β/PD-L1 blockade in mouse models of squamous cell carcinoma (SCC). The results emphasize the potential of combined TGF-β/PD-L1 targeting and provide important clues to guide personalized SCC immunotherapy.

Combinatorial Virtual Library Screening Study of Transforming Growth Factor-β2-Chondroitin Sulfate System

Transforming growth factor-beta (TGF-β), a member of the TGF-β cytokine superfamily, is known to bind to sulfated glycosaminoglycans (GAGs), but the nature of this interaction remains unclear. In a recent study, we found that preterm human milk TGF-β2 is sequestered by chondroitin sulfate (CS) in its proteoglycan form. To understand the molecular basis of the TGF-β2-CS interaction, we utilized the computational combinatorial virtual library screening (CVLS) approach in tandem with molecular dynamics (MD) simulations. All possible CS oligosaccharides were generated in a combinatorial manner to give 24 di- (CS02), 192 tetra- (CS04), and 1536 hexa- (CS06) saccharides. This library of 1752 CS oligosaccharides was first screened against TGF-β2 using the dual filter CVLS algorithm in which the GOLDScore and root-mean-square-difference (RMSD) between the best bound poses were used as surrogate markers for in silico affinity and in silico specificity. CVLS predicted that both the chain length and level of sulfation are critical for the high affinity and high specificity recognition of TGF-β2. Interestingly, CVLS led to identification of two distinct sites of GAG binding on TGF-β2. CVLS also deduced the preferred composition of the high specificity hexasaccharides, which were further assessed in all-atom explicit solvent MD simulations. The MD results confirmed that both sites of binding form stable GAG-protein complexes. More specifically, the highly selective CS chains were found to engage the TGF-β2 monomer with high affinity. Overall, this work present key principles of recognition with regard to the TGF-β2-CS system. In the process, it led to the generation of the in silico library of all possible CS oligosaccharides, which can be used for advanced studies on other protein-CS systems. Finally, the study led to the identification of unique CS sequences that are predicted to selectively recognize TGF-β2 and may out-compete common natural CS biopolymers.

Transforming growth factor-beta1 and myeloid-derived suppressor cells: A cancerous partnership

Transforming growth factor-beta1 (TGF-β1) plays a crucial role in tumor progression. It can inhibit early cancer stages but promotes tumor growth and development at the late stages of tumorigenesis. TGF-β1 has a potent immunosuppressive function within the tumor microenvironment that largely contributes to tumor cells' immune escape and reduction in cancer immunotherapy responses. Likewise, myeloid-derived suppressor cells (MDSCs) have been postulated as leading tumor promoters and a hallmark of cancer immune evasion mechanisms. This review attempts to analyze the prominent roles of both TGF-β1 and MDSCs and their interplay in cancer immunity. Furthermore, therapies against either TGF-β1 or MDSCs, and their potential synergistic combination with immunotherapies are discussed. Simultaneous TGF-β1 and MDSCs inhibition suggest a potential improvement in immunotherapy or subverted tumor immune resistance.

Leukoplakia and Immunology: New Chemoprevention Landscapes?

Oral potentially malignant disorders (OPMDs) comprise a range of clinical-pathological alterations frequently characterized by an architectural and cytological derangements upon histological analysis. Among them, oral leukoplakia is the most common type of these disorders. This work aims to analyze the possible use of drugs such as immunochemopreventive agents for OPMDs. Chemoprevention is the use of synthetic or natural compounds for the reversal, suppression, or prevention of a premalignant lesion conversion to malignant form. Experimental and in vivo data offer us the promise of molecular prevention through immunomodulation; however, currently, there is no evidence for the efficacy of these drugs in the chemoprevention action. Alternative ways to deliver drugs, combined use of molecules with complementary antitumor activities, diet influence, and better definition of individual risk factors must also be considered to reduce toxicity, improve compliance to the protocol treatment and offer a better individualized prevention. In addition, we must carefully reconsider the mode of action of many traditional cancer chemoprevention agents on the immune system, such as enhancing immunosurveillance and reversing the immune evasion. Several studies emphasize the concept of green chemoprevention as an alternative approach to accent healthy lifestyle changes in order to decrease the incidence of HNSCC.