Ultraviolet-radiation-induced inflammation promotes angiotropism and metastasis in melanoma. Nature. 2014;507:109-113. [PMID: 24572365 DOI: 10.1038/nature13111]

Association between inflammatory factors and melanoma: a bidirectional Mendelian randomization study

PURPOSE

This study performed a bidirectional Mendelian randomization (MR) analysis to elucidate the causal relationships of C-reactive protein and 41 inflammatory regulators with melanoma, including data from UK Biobank, Cardiovascular Risk in Young Finns Study, and Cohorts for Inflammation Work Group.

METHODS

We selected the inverse variance weighting (IVW) to merge the estimated causal effects of multiple SNPs into a weighted average. To evaluate the heterogeneities of IVW, the Cochran Q statistic, and I2 index were used. What's more, several sensitivity analyses were employed, including IVW, MR-Egger, weighted median, and Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO).

RESULTS

With SNPs reaching P < 5 × 10-8, the analyses findings revealed that IL-16 had a significant positively association with genetically risk of melanoma (ORIVW: 1.05; 95% CI: 1.03-1.07; P < 0.001), and high levels of MCP1 (ORIVW: 1.13; 95% CI: 1.03-1.23; P = 0.01) were suggestively associated with melanoma susceptibility. What's more, TNF-β (ORIVW: 1.07; 95% CI: 1.01-1.13; P = 0.02) and IL-8 (ORIVW: 1.08, 95% CI: 1.01-1.16; P = 0.03) were demonstrated a positive association with the risk of melanoma under a less stringent cut-off (P < 5 × 10-6). Conversely, we found a facilitative effect of melanoma susceptibility on IP-10 and inhibitory effects on IL-6, IL-1b, and GRO-α.

CONCLUSION

The genetic evidence that we have uncovered indicates a potential association between the levels of specific inflammatory markers (IL-16, IL-8, MCP-1, and TNF-β) and the risk of melanoma. Further research is imperative to translate these findings into clinical applications.

Transactivation of Met signaling by oncogenic Gnaq drives the evolution of melanoma in Hgf-Cdk4 mice

Recent pan-cancer genomic analyses have identified numerous oncogenic driver mutations that occur in a cell-type and tissue-specific distribution. For example, oncogenic mutations in Braf and Nras genes arise predominantly in melanocytic neoplasms of the epidermis, while oncogenic mutations in Gnaq/11 genes arise mostly in melanocytic lesions of the dermis or the uvea. The mechanisms promoting cell-type and tissue-specific oncogenic events currently remain poorly understood. Here, we report that Gnaq/11 hotspot mutations occur as early oncogenic drivers during the evolution of primary melanomas in Hgf-Cdk4 mice. Additional single base substitutions in the Trp53 gene and structural chromosomal aberrations favoring amplifications of the chromosomal region containing the Met receptor gene accumulate during serial tumor transplantation and in cell lines established in vitro. Mechanistically, we found that the GnaqQ209L mutation transactivates the Met receptor. Overexpression of oncogenic GnaqQ209L in the immortalized melanocyte cell line promoted in vivo growth that was enhanced by transgenic Hgf expression in the tumor microenvironment. This cross-signaling mechanism explains the selection of oncogenic Gnaq/11 in primary Hgf-Cdk4 melanomas and provides an example of how oncogenic driver mutations, intracellular signaling cascades, and microenvironmental cues cooperate to drive cancer development in a tissue-specific fashion.

Involvement of RAGE in radiation-induced acquisition of malignant phenotypes in human glioblastoma cells

Glioblastoma (GBM), a highly aggressive malignant tumor of the central nervous system, is mainly treated with radiotherapy. However, since irradiation may lead to the acquisition of migration ability by cancer cells, thereby promoting tumor metastasis and invasion, it is important to understand the mechanism of cell migration enhancement in order to prevent recurrence of GBM. The receptor for advanced glycation end products (RAGE) is a pattern recognition receptor activated by high mobility group box 1 (HMGB1). In this study, we found that RAGE plays a role in the enhancement of cell migration by γ-irradiation in human GBM A172 cells. γ-Irradiation induced actin remodeling, a marker of motility acquisition, and enhancement of cell migration in A172 cells. Both phenotypes were suppressed by specific inhibitors of RAGE (FPS-ZM1 and TTP488) or by knockdown of RAGE. The HMGB1 inhibitor ethyl pyruvate similarly suppressed γ-irradiation-induced enhancement of cell migration. In addition, γ-irradiation-induced phosphorylation of STAT3 was suppressed by RAGE inhibitors, and a STAT3 inhibitor suppressed γ-irradiation-induced enhancement of cell migration, indicating that STAT3 is involved in the migration enhancement downstream of RAGE. Our results suggest that HMGB1-RAGE-STAT3 signaling is involved in radiation-induced enhancement of GBM cell migration, and may contribute to GBM recurrence by promoting metastasis and invasion.

Neutrophil extracellular traps (NETs) and fibrotic diseases

Fibrosis, a common cause and serious outcome of organ failure that can affect any organ, is responsible for up to 45% of all deaths in various clinical settings. Both preclinical models and clinical trials investigating various organ systems have shown that fibrosis is a highly dynamic process. Although many studies have sought to gain understanding of the mechanism of fibrosis progression, their findings have been mixed. In recent years, increasing evidence indicates that neutrophil extracellular traps (NETs) are involved in many inflammatory and autoimmune disorders and participate in the regulation of fibrotic processes in various organs and systems. In this review, we summarize the current understanding of the role of NETs in fibrosis development and progression and their possibility as therapeutic targets.

Rosacea is strongly associated with melanoma in Caucasians

Rosacea is often considered a cosmetic problem but is known to be associated with a variety of comorbidities. To identify such risks, we generated two age- and sex-matched real-world cohorts of 122,444 patients each with and without rosacea. In contrast to earlier studies, we found significant associations with malignant melanoma (OR 6.02, 95% CI 5.76-6.32). This association does not exist for an Asian sub-cohort, which could explain previous inconclusive or conflicting reports. Several strongly associated comorbidities like visual disturbances (ICD-10: H53-H54; OR 4.80, 4.68-4.92), metabolic disorders (E73-E79; OR 3.17, 3.11-3.22), joint problems (M25; OR 4.16, 4.08-4.25) and type 2 diabetes (E11; OR 1.62, 1.58-1.65) should be watched as a risk for rosacea patients. Rosacea is associated with some comorbidities and ethnicity may be a risk factor in melanoma development. The retrospective nature of this study and the sole use of ICD-10 code based filtering calls for future validation of our findings. Additionally, confounding factors such as skin type and previous UV exposure should be included in future studies.

Immune Cell Migration to Cancer

Immune cell migration is required for the development of an effective and robust immune response. This elegant process is regulated by both cellular and environmental factors, with variables such as immune cell state, anatomical location, and disease state that govern differences in migration patterns. In all cases, a major factor is the expression of cell surface receptors and their cognate ligands. Rapid adaptation to environmental conditions partly depends on intrinsic cellular immune factors that affect a cell's ability to adjust to new environment. In this review, we discuss both myeloid and lymphoid cells and outline key determinants that govern immune cell migration, including molecules required for immune cell adhesion, modes of migration, chemotaxis, and specific chemokine signaling. Furthermore, we summarize tumor-specific elements that contribute to immune cell trafficking to cancer, while also exploring microenvironment factors that can alter these cellular dynamics within the tumor in both a pro and antitumor fashion. Specifically, we highlight the importance of the secretome in these later aspects. This review considers a myriad of factors that impact immune cell trajectory in cancer. We aim to highlight the immunotherapeutic targets that can be harnessed to achieve controlled immune trafficking to and within tumors.

The role of ANXA1 in the tumor microenvironment

Annexin A1 (ANXA1) is widely expressed in a variety of body tissues and cells and is also involved in tumor development through multiple pathways. The invasion, metastasis, and immune escape of tumor cells depend on the interaction between tumor cells and their surrounding environment. Research shows that ANXA1 can act on a variety of cells in the tumor microenvironment (TME), and subsequently affect the proliferation, invasion and metastasis of tumors. This article describes the role of ANXA1 in the various components of the tumor microenvironment and its mechanism of action, as well as the existing clinical treatment measures related to ANXA1. These findings provide insight for the further design of strategies targeting ANXA1 for the diagnosis and treatment of malignant tumors.

A near-IR ratiometric fluorescent probe for the precise tracking of senescence: a multidimensional sensing assay of biomarkers in cell senescence pathways

Senescence is a complex physiological process that can be induced by a range of factors, and cellular damage caused by reactive oxygen species (ROS) is one of the major triggers. In order to learn and solve age-related diseases, tracking strategies through biomarkers, including senescence-associated β-galactosidase (SA-β-gal), with high sensitivity and accuracy, have been considered as a promising solution. However, endogenous β-gal accumulation is not only associated with senescence but also with other physiological processes. Therefore, additional assays are needed to define cellular senescence further. In this work, a fancy fluorescent probe SA-HCy-1 for accurately monitoring senescence is developed, with SA-β-gal and HClO as targets under high lysosomal pH conditions (pH > 6.0) specifically, on account of the role β-gal commonly played as an ovarian cancer biomarker. Therefore, precise tracking of cellular senescence could be achieved in view of these three dimensions, with response in dual fluorescence channels providing a ratiometric sensing pattern. This elaborate strategy has been verified to be suitable for biological applications by skin photo-aging evaluation and cellular passage tracing, displaying a significantly improved sensitivity compared with the commercial X-gal kit measurement.

Anti-cancer mechanisms of natural isoflavones against melanoma

The incidence of skin-related neoplasms has generally increased in recent years. Melanoma arises from malignant mutations in melanocytes in the basal layer of the epidermis and is a fatal skin cancer that seriously threatens human health. Isoflavones are polyphenolic compounds widely present in legumes and have drawn scientists' attention, because they have good efficacy against a variety of cancers, including melanoma, without significant toxic side effects and resistance. In this review article, we summarize the research progress of isoflavones in melanoma, including anti-melanoma roles and mechanisms of isoflavones via inhibition of tyrosinase activity, melanogenesis, melanoma cell growth, invasion of melanoma cells, and induction of apoptosis in melanoma cells. This information is important for the prevention, clinical treatment, and prognosis and survival of melanoma.

Overexpression of PIK3CG in Cancer Cells Promotes Lung Cancer Cell Migration and Metastasis Through Enhanced MMPs Expression and Neutrophil Recruitment and Activation

Metastasis is a major cause of death in lung cancer. The aim of this study is to analyze the role and mechanism of PI3K catalytic subunit gamma (PIK3CG, also known as p110γ) in lung cancer cell migration and metastasis. Knockdown (KD) and overexpression (OE) of PIK3CG expression in lung cancer cell lines A549 and H1299 in vitro cultured was achieved. Two PIK3CG-specific inhibitors, Eganelisib and CAY10505, were used to treat A549 and H1299 cells. An experimental lung metastasis mouse model was constructed using tail vein injection of LLC cells. Finally, a co-culture system was established using Transwell chambers. Compared with the NC group, the number of cells that completed migration and the expression levels of matrix metalloproteinases (MMPs) were significantly reduced in the KD group and Eganelisib and CAY10505 treatment groups, while the number of cells that migrated successfully and the expression levels of MMPs were significantly increased in the OE group. Lung tissues of mice injected with PIK3CG-stabilized overexpressed LLC cells showed more pronounced lung cancer growth, lung metastatic nodules, neutrophil infiltration and MMPs expression. Co-culture with neutrophils, soluble extracts of neutrophils and cathepsin G all promoted the migration of lung cancer cells. PIK3CG overexpression in tumor cells significantly promoted the migration and metastasis of lung cancer cell.

Can angiotropism and lymphovascular invasion refine the current cutaneous melanoma staging system?

BACKGROUND

Several prognostic factors for primary cutaneous melanoma (PCM) have been identified, and these predict metastasis and survival, to a certain extent. We sought to determine the frequency of angiotropism (AT) and lymphovascular invasion (LVI) in PCM and the relationship between AT, LVI, and other clinicopathological parameters and patient's prognosis.

METHODS

This study included 538 cases of PCM diagnosed between 2003 and 2016. It comprised 246 females and 292 males whose clinicopathological variables were evaluated with respect to LVI and AT using univariate and multivariate analyses. Overall survival (OS) was assessed by Kaplan-Meier (KM) analysis and Cox regression multivariate analysis.

RESULTS

AT occurred more frequently than LVI. Ulceration, mitotic rate, and Breslow thickness were found to be highly associated with both LVI and AT (p < 0.01). All LVI+ cases had AT, with a significant positive correlation (p < 0.01). Both AT and LVI predicted lymph node (LN) metastasis (odds ratio [OR] = 1.47, 1.12, respectively). Multivariate analysis showed LN metastasis, Breslow thickness, LVI, and AT as predictors of OS. LVI and AT independently predicted adverse OS by Cox regression analysis (hazard ratio [HR] = 1.66, 1.49, respectively) and with KM survival analysis.

CONCLUSION

AT is a marker for angiotropic extravascular migratory tumor spread (angiotropic EVMM), and LVI is a marker for intra-lymphovascular tumor spread. Both predict poor prognosis. Given its ease of detection, AT could be adopted as a histologpathological feature in the routine assessment of primary cutaneous malignant melanoma cases.

Mitochondrial DNA mutations drive aerobic glycolysis to enhance checkpoint blockade response in melanoma

The mitochondrial genome (mtDNA) encodes essential machinery for oxidative phosphorylation and metabolic homeostasis. Tumor mtDNA is among the most somatically mutated regions of the cancer genome, but whether these mutations impact tumor biology is debated. We engineered truncating mutations of the mtDNA-encoded complex I gene, Mt-Nd5, into several murine models of melanoma. These mutations promoted a Warburg-like metabolic shift that reshaped tumor microenvironments in both mice and humans, consistently eliciting an anti-tumor immune response characterized by loss of resident neutrophils. Tumors bearing mtDNA mutations were sensitized to checkpoint blockade in a neutrophil-dependent manner, with induction of redox imbalance being sufficient to induce this effect in mtDNA wild-type tumors. Patient lesions bearing >50% mtDNA mutation heteroplasmy demonstrated a response rate to checkpoint blockade that was improved by ~2.5-fold over mtDNA wild-type cancer. These data nominate mtDNA mutations as functional regulators of cancer metabolism and tumor biology, with potential for therapeutic exploitation and treatment stratification.

NK-cell-elicited gasdermin-D-dependent hepatocyte pyroptosis induces neutrophil extracellular traps that facilitate HBV-related acute-on-chronic liver failure

BACKGROUND AND AIMS

HBV infection is a major etiology of acute-on-chronic liver failure (ACLF). At present, the pattern and regulation of hepatocyte death during HBV-ACLF progression are still undefined. Evaluating the mode of cell death and its inducers will provide new insights for developing therapeutic strategies targeting cell death. In this study, we aimed to elucidate whether and how immune landscapes trigger hepatocyte death and lead to the progression of HBV-related ACLF.

APPROACH AND RESULTS

We identified that pyroptosis represented the main cell death pattern in the liver of patients with HBV-related ACLF. Deficiency of MHC-I in HBV-reactivated hepatocytes activated cytotoxic NK cells, which in turn operated in a perforin/granzyme-dependent manner to trigger GSDMD/caspase-8-dependent pyroptosis of hepatocytes. Neutrophils selectively accumulated in the pyroptotic liver, and HMGB1 derived from the pyroptotic liver constituted an important factor triggering the generation of pathogenic extracellular traps in neutrophils (NETs). Clinically, elevated plasma levels of myeloperoxidase-DNA complexes were a promising prognostic biomarker for HBV-related ACLF. More importantly, targeting GSDMD pyroptosis-HMGB1 release in the liver abrogates NETs that intercept the development of HBV-related ACLF.

CONCLUSIONS

Studying the mechanisms that selectively modulate GSDMD-dependent pyroptosis, as well as its immune landscapes, will provide a novel strategy for restoring the liver function of patients with HBV-related ACLF.

CD93 maintains endothelial barrier function and limits metastatic dissemination

Compromised vascular integrity facilitates extravasation of cancer cells and promotes metastatic dissemination. CD93 has emerged as a target for antiangiogenic therapy, but its importance for vascular integrity in metastatic cancers has not been evaluated. Here, we demonstrate that CD93 participates in maintaining the endothelial barrier and reducing metastatic dissemination. Primary melanoma growth was hampered in CD93-/- mice, but metastatic dissemination was increased and associated with disruption of adherens and tight junctions in tumor endothelial cells and elevated expression of matrix metalloprotease 9 at the metastatic site. CD93 directly interacted with vascular endothelial growth factor receptor 2 (VEGFR2) and its absence led to VEGF-induced hyperphosphorylation of VEGFR2 in endothelial cells. Antagonistic anti-VEGFR2 antibody therapy rescued endothelial barrier function and reduced the metastatic burden in CD93-/- mice to wild-type levels. These findings reveal a key role of CD93 in maintaining vascular integrity, which has implications for pathological angiogenesis and endothelial barrier function in metastatic cancer.

Current insights and future perspectives of ultraviolet radiation (UV) exposure: Friends and foes to the skin and beyond the skin

Ultraviolet (UV) radiation is ubiquitous in the environment, which has been classified as an established human carcinogen. As the largest and outermost organ of the body, direct exposure of skin to sunlight or UV radiation can result in sunburn, inflammation, photo-immunosuppression, photoaging and even skin cancers. To date, there are tactics to protect the skin by preventing UV radiation and reducing the amount of UV radiation to the skin. Nevertheless, deciphering the essential regulatory mechanisms may pave the way for therapeutic interventions against UV-induced skin disorders. Additionally, UV light is considered beneficial for specific skin-related conditions in medical UV therapy. Recent evidence indicates that the biological effects of UV exposure extend beyond the skin and include the treatment of inflammatory diseases, solid tumors and certain abnormal behaviors. This review mainly focuses on the effects of UV on the skin. Moreover, novel findings of the biological effects of UV in other organs and systems are also summarized. Nevertheless, the mechanisms through which UV affects the human organism remain to be fully elucidated to achieve a more comprehensive understanding of its biological effects.

CCL2 promotes metastasis and epithelial-mesenchymal transition of non-small cell lung cancer via PI3K/Akt/mTOR and autophagy pathways

In non-small cell lung cancer (NSCLC), metastasis is the most common phenotype, and autophagy plays a vital role in its regulation. However, there are limited data on how autophagy-related genes and metastasis-related genes affect NSCLC progression. Our goal was to identify the genes that regulate autophagy and metastasis in NSCLC, and to assess the underlying mechanisms in this current study. RNA sequencing data from public databases were used to screen differentially expressed autophagy- and metastasis-associated genes. Enrichment analyses and immune correlations were conducted to identify hub genes and potential regulating pathways in NSCLC. In this study, we found that CCL2 expression was highly expressed in NSCLC tissues and high CCL2 level was correlated with strong infiltration in lung tissues from NSCLC patients. Overexpression of CCL2 can enhance the metastasis of NSCLC cells in nude mice. Furthermore, CCL2 activated the PI3K/Akt/mTOR signalling pathway axis, promoted epithelial-mesenchymal transition (EMT), and blocked the autophagic flux in NSCLC cells. Therefore, our results indicate that CCL2 promotes metastasis and EMT of NSCLC via PI3K/Akt/mTOR axis and autophagy signalling pathways. We believe that CCL2 could be a probable target for the diagnosis and therapeutics of NSCLC, and this study may expand our understanding of lung cancer.

Loss of Pip4k2c confers liver-metastatic organotropism through insulin-dependent PI3K-AKT pathway activation

Liver metastasis (LM) confers poor survival and therapy resistance across cancer types, but the mechanisms of liver-metastatic organotropism remain unknown. Here, through in vivo CRISPR-Cas9 screens, we found that Pip4k2c loss conferred LM but had no impact on lung metastasis or primary tumor growth. Pip4k2c-deficient cells were hypersensitized to insulin-mediated PI3K/AKT signaling and exploited the insulin-rich liver milieu for organ-specific metastasis. We observed concordant changes in PIP4K2C expression and distinct metabolic changes in 3,511 patient melanomas, including primary tumors, LMs and lung metastases. We found that systemic PI3K inhibition exacerbated LM burden in mice injected with Pip4k2c-deficient cancer cells through host-mediated increase in hepatic insulin levels; however, this circuit could be broken by concurrent administration of an SGLT2 inhibitor or feeding of a ketogenic diet. Thus, this work demonstrates a rare example of metastatic organotropism through co-optation of physiological metabolic cues and proposes therapeutic avenues to counteract these mechanisms.

Dormancy of cutaneous melanoma

Many cancer-related deaths including melanoma result from metastases that develop months or years after the initial cancer therapy. Even the most effective drugs and immune therapies rarely eradicate all tumor cells. Instead, they strongly reduce cancer burden, permitting dormant cancer cells to persist in niches, where they establish a cellular homeostasis with their host without causing clinical symptoms. Dormant cancers respond poorly to most drugs and therapies since they do not proliferate and hide in niches. It therefore remains a major challenge to develop novel therapies for dormant cancers. In this review we focus on the mechanisms regulating the initiation of cutaneous melanoma dormancy as well as those which are involved in reawakening of dormant cutaneous melanoma cells. In recent years the role of neutrophils and niche components in reawakening of melanoma cells came into focus and indicate possible future therapeutic applications. Sophisticated in vitro and in vivo melanoma dormancy models are needed to make progress in this field and are discussed.

Photochromic Perovskite Nanocrystals for Ultraviolet Dosimetry

Excessive ultraviolet (UV) radiation has serious damage to human's health, therefore the development of visible, portable, and wearable sensor for monitoring UV radiation, especially the cumulative UV dosage, is highly desired but full of challenges. Herein, a wearable and flexible UV dosimeter based on photochromic perovskite nanocrystals (PNCs) is designed. The obtained CsPbCl3 PNCs dispersed in dibromomethane (PNCs-DBM) undergo continuous, vivid, and multiple (from very weak purple to blue, cyan, and finally strong green) color change in response to UV radiation. It is demonstrated that the UV-induced degradation of DBM and subsequent anion-exchange reaction between CsPbCl3 and Br- , play a crucial role in the color change of PNCs-DBM. The properties of continuous fluorescence color change and enhanced fluorescence intensity enable the construction of sensitive and visible UV dosimeter. Furthermore, by integrated photochromic PNCs with flexible bracelet or PDMS substrate, a wearable UV sensor or a multi-indicator array for the detection of solar UV dosage is developed. This work may advance the fundamental understanding about photochromic perovskite, and show promising application of perovskite nanomaterials in easily fabricated, low-cost, visualized, and wearable solar UV dosimeter.

The role of intestinal flora on tumor immunotherapy: recent progress and treatment implications

Immunotherapy, specifically immune checkpoint inhibitors, has emerged as a promising approach for treating malignant tumors. The gut, housing approximately 70 % of the body's immune cells, is abundantly populated with gut bacteria that actively interact with the host's immune system. Different bacterial species within the intestinal flora are in a delicate equilibrium and mutually regulate each other. However, when this balance is disrupted, pathogenic microorganisms can dominate, adversely affecting the host's metabolism and immunity, ultimately promoting the development of disease. Emerging researches highlight the potential of interventions such as fecal microflora transplantation (FMT) to improve antitumor immune response and reduce the toxicity of immunotherapy. These remarkable findings suggest the major role of intestinal flora in the development of cancer immunotherapy and led us to the hypothesis that intestinal flora transplantation may be a new breakthrough in modifying immunotherapy side effects.

Exosomes from hypoxic pretreated ADSCs attenuate ultraviolet light-induced skin injury via GLRX5 delivery and ferroptosis inhibition

Accumulation studies have found that adipose-derived stem cell (ADSC) exosomes have anti-oxidant and anti-inflammatory characteristics. The current study verified their therapeutic potential to elucidate mechanisms of ADSC exosome actions in ultraviolet B (UVB) light-induced skin injury. Exosomes were isolated from ADSCs and hypoxic pretreated ADSCs. Next-generation sequencing (NGS) was applied to characterize differential mRNA expression. A UV-induced mice skin injury model was generated to investigate therapeutic effects regarding the exosomes via immunofluorescence and ELISA analysis. Regulatory mechanisms were illustrated using luciferase report analysis and in vitro experiments. The results demonstrated that exosomes from hypoxic pretreated ADSCs (HExos) inhibited UVB light-induced vascular injury by reversing reactive oxygen species, inflammatory factor expression and excessive collagen degradation. NGS showed that HExos inhibits UV-induced skin damage via GLRX5 delivery, while GLRX5 downregulation inhibited the therapeutic effect of HExos on UV-induced skin damage. GLRX5 upregulation increased the protective Exo effect on UV-induced skin and EPC damage by inhibiting ferroptosis, inflammatory cytokine expression and excessive collagen degradation. Therefore, the data indicate that HExos attenuate UV light-induced skin injury via GLRX5 delivery and ferroptosis inhibition.

Neutrophil-to-Lymphocyte Ratio (NLR) in NSCLC, Gastrointestinal, and Other Solid Tumors: Immunotherapy and Beyond

In the era of immunotherapy, identifying biomarkers of immune system activation has become a high-priority challenge. The blood neutrophil-to-lymphocyte ratio (NLR) has been largely investigated as a biomarker in several cancer types. NLR values have been shown to mirror the tumor-induced inflammatory status and have been demonstrated to be a reliable prognostic tool across stages of disease and therapeutic approaches. When integrated with other biomarkers of response to immunotherapy, such as PD-L1, tumor mutational burden, and tumor-associated immune cells, the NLR may allow to further stratify patients with different likelihoods of deriving a significant clinical benefit. However, despite its accessibility, low cost, and easy interpretation, the NLR is still poorly used as a prognostic tool in daily clinical practice. In this review, we analyze the role of the NLR in defining the relationship between cancer and the immune system, its usefulness in daily clinical practice, and its relationship with other established or emerging biomarkers of immunotherapy outcomes.

Vascular co-option in resistance to anti-angiogenic therapy

Three different mechanisms of neovascularization have been described in tumor growth, including sprouting angiogenesis, intussusceptive microvascular growth and glomeruloid vascular proliferation. Tumors can also grow by means of alternative mechanisms including vascular co-option, vasculogenic mimicry, angiotropism, and recruitment of endothelial precursor cells. Vascular co-option occurs in tumors independently of sprouting angiogenesis and the non-angiogenic cancer cells are described as exploiting pre-existing vessels. Vascular co-option is more frequently observed in tumors of densely vascularized organs, including the brain, lung and liver, and vascular co-option represents one of the main mechanisms involved in metastasis, as occurs in liver and lung, and resistance to anti-angiogenic therapy. The aim of this review article is to analyze the role of vascular co-option as mechanism through which tumors develop resistance to anti-angiogenic conventional therapeutic approaches and how blocking co-option can suppress tumor growth.

Tumor endothelial cell autophagy is a key vascular-immune checkpoint in melanoma

Tumor endothelial cells (TECs) actively repress inflammatory responses and maintain an immune-excluded tumor phenotype. However, the molecular mechanisms that sustain TEC-mediated immunosuppression remain largely elusive. Here, we show that autophagy ablation in TECs boosts antitumor immunity by supporting infiltration and effector function of T-cells, thereby restricting melanoma growth. In melanoma-bearing mice, loss of TEC autophagy leads to the transcriptional expression of an immunostimulatory/inflammatory TEC phenotype driven by heightened NF-kB and STING signaling. In line, single-cell transcriptomic datasets from melanoma patients disclose an enriched InflammatoryHigh /AutophagyLow TEC phenotype in correlation with clinical responses to immunotherapy, and responders exhibit an increased presence of inflamed vessels interfacing with infiltrating CD8+ T-cells. Mechanistically, STING-dependent immunity in TECs is not critical for the immunomodulatory effects of autophagy ablation, since NF-kB-driven inflammation remains functional in STING/ATG5 double knockout TECs. Hence, our study identifies autophagy as a principal tumor vascular anti-inflammatory mechanism dampening melanoma antitumor immunity.

Childhood sunburn and risk of melanoma and non-melanoma skin cancer: a Mendelian randomization study

Previous evidence has suggested that childhood sunburn could be a risk factor for cutaneous malignant melanoma (MM) and non-melanoma skin cancer (NMSC). However, existing observational studies could not reveal the causal associations genetically. This study aimed to investigate whether there was a genetic causal relationship between childhood sunburn and skin cancers. Univariable Mendelian randomization (MR) and Causal Analysis Using Summary Effect analysis was carried out for causal estimates and evaluation for the horizontal pleiotropy. Multivariable MR and the mediation effects analysis were used to test whether the causal associations were mediated by potential confounders. A suggestively significant causal association between childhood sunburn and MM was indicated (OR = 4.74; 95% CI: 1.31-17.19; p = 1.79E-02). Genetically predicted childhood sunburn was significantly associated with increased risk of overall melanoma in situ (MIS) (OR = 4.02; 95% CI: 2.00-8.08; p = 9.40E-05), MIS of face (OR = 18.28; 95% CI: 5.28-63.35; p = 4.59E-06), and MIS of trunk (OR = 7.05; 95% CI: 2.06-24.13; p = 1.88E-03). Similar trends were found for childhood sunburn and NMSC (OR = 8.16; 95% CI: 6.07-10.99; p = 1.53E-20), including both basal cell carcinoma (BCC) (OR = 3.76; 95% CI:2.96-4.77; p = 2.19E-08) and squamous cell carcinoma (SCC) (OR = 7.44; 95% CI: 5.09-10.87; p = 2.19E-08). After adjustment for hair and skin color, facial ageing, vitamin D levels, body mass index, alcohol consumption, and smoking status, childhood sunburn showed an independent association with MIS, MIS of face, MIS of trunk, as well as NMSC, including both BCC and SCC. Mediation analysis showed no significant mediation effect. This study demonstrated a causal relationship between childhood sunburn and the risk of both MM and NMSC, which suggested that enhanced screening and prevention for childhood sunburn could contribute to the early detection and decreased risk of MM and NMSC.

The multifunctional protein HMGB1: 50 years of discovery

Fifty years since the initial discovery of HMGB1 in 1973 as a structural protein of chromatin, HMGB1 is now known to regulate diverse biological processes depending on its subcellular or extracellular localization. These functions include promoting DNA damage repair in the nucleus, sensing nucleic acids and inducing innate immune responses and autophagy in the cytosol and binding protein partners in the extracellular environment and stimulating immunoreceptors. In addition, HMGB1 is a broad sensor of cellular stress that balances cell death and survival responses essential for cellular homeostasis and tissue maintenance. HMGB1 is also an important mediator secreted by immune cells that is involved in a range of pathological conditions, including infectious diseases, ischaemia-reperfusion injury, autoimmunity, cardiovascular and neurodegenerative diseases, metabolic disorders and cancer. In this Review, we discuss the signalling mechanisms, cellular functions and clinical relevance of HMGB1 and describe strategies to modify its release and biological activities in the setting of various diseases.

Prostaglandin E2 Exposure Disrupts E-Cadherin/Caveolin-1-Mediated Tumor Suppression to Favor Caveolin-1-Enhanced Migration, Invasion, and Metastasis in Melanoma Models

Caveolin-1 (CAV1) is a membrane-bound protein that suppresses tumor development yet also promotes metastasis. E-cadherin is important in CAV1-dependent tumor suppression and prevents CAV1-enhanced lung metastasis. Here, we used murine B16F10 and human A375 melanoma cells with low levels of endogenous CAV1 and E-cadherin to unravel how co-expression of E-cadherin modulates CAV1 function in vitro and in vivo in WT C57BL/6 or Rag-/- immunodeficient mice and how a pro-inflammatory environment generated by treating cells with prostaglandin E2 (PGE2) alters CAV1 function in the presence of E-cadherin. CAV1 expression augmented migration, invasion, and metastasis of melanoma cells, and these effects were abolished via transient co-expression of E-cadherin. Importantly, exposure of cells to PGE2 reverted the effects of E-cadherin expression and increased CAV1 phosphorylation on tyrosine-14 and metastasis. Moreover, PGE2 administration blocked the ability of the CAV1/E-cadherin complex to prevent tumor formation. Therefore, our results support the notion that PGE2 can override the tumor suppressor potential of the E-cadherin/CAV1 complex and that CAV1 released from the complex is phosphorylated on tyrosine-14 and promotes migration/invasion/metastasis. These observations provide direct evidence showing how a pro-inflammatory environment caused here via PGE2 administration can convert a potent tumor suppressor complex into a promoter of malignant cell behavior.

The invasive margin of early-stage human colon tumors is infiltrated with neutrophils of an antitumoral phenotype

Neutrophils infiltrate several types of cancer; however, whether their presence is associated with disease progression remains controversial. Here, we show that colon tumors overexpress neutrophil chemoattractants compared to healthy tissues, leading to their recruitment to the invasive margin and the central part of colon tumors. Of note, tumor-associated neutrophils expressing tumor necrosis factor α, which usually represents an antitumoral phenotype, were predominantly located in the invasive margin. Tumor-associated neutrophils from the invasive margin displayed an antitumoral phenotype with higher ICAM-1 and CD95 expression than neutrophils from healthy adjacent tissues. A higher neutrophil/lymphocyte ratio was found at later stages compared to the early phases of colon cancer. A neutrophil/lymphocyte ratio ≤3.5 predicted tumor samples had significantly more neutrophils at the invasive margin and the central part. Moreover, tumor-associated neutrophils at the invasive margin of early-stage tumors showed higher ICAM-1 and CD95 expression. Coculture of colon cancer cell lines with primary neutrophils induced ICAM-1 and CD95 expression, confirming our in situ findings. Thus, our data demonstrate that tumor-associated neutrophils with an antitumoral phenotype characterized by high ICAM-1 and CD95 expression infiltrate the invasive margin of early-stage colon tumors, suggesting that these cells can combat the disease at its early courses. The presence of tumor-associated neutrophils with antitumoral phenotype could help predict outcomes of patients with colon cancer.

Perivascular niches: critical hubs in cancer evolution

Tumors are heterogeneous ecosystems in which cancer cells coexist within a complex tumor immune microenvironment (TIME). The malignant, stromal, and immune cell compartments establish a plethora of bidirectional cell-cell communication crosstalks that influence tumor growth and metastatic dissemination, which we are only beginning to understand. Cancer cells either co-opt or promote the formation of new blood and lymphatic vessels to cope with their need for nutrients and oxygen. Recent studies have highlighted additional key roles for the tumor vasculature and have identified the perivascular niche as a cellular hub, where intricate and dynamic cellular interactions promote cancer stemness, immune evasion, dormancy, and metastatic spreading. Here, we review these findings, and discuss how they may be exploited therapeutically.

Melanoma-derived soluble mediators modulate neutrophil biological properties and the release of neutrophil extracellular traps

Polymorphonuclear neutrophils (PMNs) are the main effector cells in the inflammatory response. The significance of PMN infiltration in the tumor microenvironment remains unclear. Metastatic melanoma is the most lethal skin cancer with an increasing incidence over the last few decades. This study aimed to investigate the role of PMNs and their related mediators in human melanoma. Highly purified human PMNs from healthy donors were stimulated in vitro with conditioned media (CM) derived from the melanoma cell lines SKMEL28 and A375 (melanoma CM), and primary melanocytes as controls. PMN biological properties (chemotaxis, survival, activation, cell tracking, morphology and NET release) were evaluated. We found that the A375 cell line produced soluble factors that promoted PMN chemotaxis, survival, activation and modification of morphological changes and kinetic properties. Furthermore, in both melanoma cell lines CM induced chemotaxis, activation and release of neutrophil extracellular traps (NETs) from PMNs. In contrast, the primary melanocyte CM did not modify the biological behavior of PMNs. In addition, serum levels of myeloperoxidase, matrix metalloprotease-9, CXCL8/IL-8, granulocyte and monocyte colony-stimulating factor and NETs were significantly increased in patients with advanced melanoma compared to healthy controls. Melanoma cell lines produce soluble factors able to "educate" PMNs toward an activated functional state. Patients with metastatic melanoma display increased circulating levels of neutrophil-related mediators and NETs. Further investigations are needed to better understand the role of these "tumor-educated neutrophils" in modifying melanoma cell behavior.

Cellular and molecular characteristics of the premetastatic niches

The premetastatic niches (PMN) formed by primary tumor-derived molecules regulate distant organs and tissues to further favor tumor colonization. Targeted PMN therapy may prevent tumor metastasis in the early stages, which is becoming increasingly important. At present, there is a lack of in-depth understanding of the cellular and molecular characteristics of the PMN. Here, we summarize current research advances on the cellular and molecular characteristics of the PMN. We emphasize that PMN intervention is a potential therapeutic strategy for early prevention of tumor metastasis, which provides a promising basis for future research and clinical application.

Prognostic analysis of stereotactic radiosurgery for brain metastases: a single-center retrospective study

OBJECTIVES

Brain metastasis (BM) is a common event during the development of many cancers, and is also one of the main causes of death of patients. Stereotactic radiosurgery (SRS) is an effective treatment for BM. The prognostic effects of various clinical factors on local control (LC) and overall survival (OS) after SRS treatment are still unclear. The purpose of this study is to retrospectively analyze the intracranial progression free survival (iPFS) and OS of patients receiving SRS treatment, and explore the relationship between various clinical characteristics and patient prognosis.

MATERIALS AND METHODS

We collected the clinical information of patients who were diagnosed with BM and received SRS treatment in our center between 2018 and 2021. Univariate and multivariate Cox regression analysis and KM analysis for iPFS and OS were conducted in R software to investigate the prognostic effects of clinical characteristics.

RESULTS

In total, 183 patients that received SRS in our center were enrolled in the cohort. The median iPFS for all patients was 8.87 months (95% CI 6.9-10.6), and the median OS was 16.5 months (95% CI 12.9-20.7). BM number >  = 5 (HR 1.965 [95% CI 1.381-2.796], p < 0.001, FDR-corrected p < 0.001) was found to be strong predictor for shorter iPFS and OS. Subgroup analysis showed that patients with cumulative intracranial tumor volume (CITV) >  = 2.14 cm3 and number >  = 5 had shortest iPFS (P < 0.001) and OS (P = 0.007), compared with other subgroups. For patients with more than 5 BMs, SRS plus whole brain radiotherapy (WBRT) could achieve better local control, compared with SRS alone group (P = 0.0357). Peripheral blood inflammation indicators were associated with the prognosis of BM patients in univariate Cox analysis, but not in multivariate Cox analysis.

CONCLUSIONS

BM number is an independent prognostic factor for BM patients. The prognosis of patients in the subgroup with larger CITV and more BM is the worst. For patients with more than 5 BM, the combination of SRS and WBRT can improve the local control, but cannot prolong the OS.

IL-17 promotes melanoma through TRAF2 as a scaffold protein recruiting PIAS2 and ELAVL1 to induce EPHA5

An abnormal immune response induces melanoma development. IL-17 and the classical downstream signal STAT1 are associated with melanoma development. TRAF2 also mediates the downstream signaling of IL-17; however, its role in IL-17-stimulated melanoma remains unclear. Bioinformatic analysis revealed that TRAF2 can bind to PIAS2 (a SUMO E3 ligase), ELAVL1 (an RNA-binding protein), and EPHA5 (an ephrin receptor of the tyrosine kinase family). To elucidate the IL-17 downstream signal, the IL-17 receptor (R), STAT1, TRAF2, PIAS2, ELAVL1, and EPHA5 were knocked down before melanoma cells were treated with recombinant IL-17A protein. Co-immunoprecipitation and RNA immunoprecipitation were conducted to determine the interaction of TRAF2 with PIAS2, ELAVL1, and EPHA5 proteins, as well as the interaction of ELAVL1 protein with EPHA5 mRNA. STAT1 knockdown suppressed the proliferation and invasion triggered by IL-17A, but the suppressive effects were much weaker than those caused by IL-17R knockdown. This implies that another nonclassical signal mediates IL-17 effects. IL-17A induces TRAF2 recruitment of ELAVL1, PIAS2, and EPHA5 proteins. We speculated that ELAVL1 bound to the AU-rich elements in the 3' untranslated region of the EPHA5 mRNA, thereby enhancing mRNA stability. Furthermore, PIAS2 induced EPHA5 SUMOylation, which suppressed EPHA5 ubiquitination and degradation. Through pre- and post-translational regulation, IL-17A induced EPHA5 expression in melanoma, and EPHA5 knockdown markedly suppressed IL-17A-induced proliferation and invasion. This study revealed a non-classical signaling mechanism responsible for the effects of IL-17 in melanoma.

Nutrition and melanoma: the contribution of trace elements in onset, progression, and treatment of melanoma

Melanoma is a highly malignant and drug-resistant disease that imposes a substantial economic burden on the world. There are many studies linking trace elements to diverse types of cancers, including melanoma. This review elucidates the relationship between trace elements exposure and melanoma. It was identified that copper, manganese, selenium, zinc, iron, and many other trace elements were associated with melanoma in humans. In terms of epidemiology, different elements have different correlations with melanoma. These trace elements affect the occurrence and development of melanoma through various mechanisms, such as oxidative stress and the MAPK pathway. The literature on the role of trace elements in the pathogenesis and treatment of melanoma depicts promising prospects for this field.

The evolution and heterogeneity of neutrophils in cancers: origins, subsets, functions, orchestrations and clinical applications

Neutrophils, the most prevalent innate immune cells in humans, have garnered significant attention in recent years due to their involvement in cancer progression. This comprehensive review aimed to elucidate the important roles and underlying mechanisms of neutrophils in cancer from the perspective of their whole life cycle, tracking them from development in the bone marrow to circulation and finally to the tumor microenvironment (TME). Based on an understanding of their heterogeneity, we described the relationship between abnormal neutrophils and clinical manifestations in cancer. Specifically, we explored the function, origin, and polarization of neutrophils within the TME. Furthermore, we also undertook an extensive analysis of the intricate relationship between neutrophils and clinical management, including neutrophil-based clinical treatment strategies. In conclusion, we firmly assert that directing future research endeavors towards comprehending the remarkable heterogeneity exhibited by neutrophils is of paramount importance.

The role of the symbiotic microecosystem in cancer: gut microbiota, metabolome, and host immunome

The gut microbiota is not just a simple nutritional symbiosis that parasitizes the host; it is a complex and dynamic ecosystem that coevolves actively with the host and is involved in a variety of biological activities such as circadian rhythm regulation, energy metabolism, and immune response. The development of the immune system and immunological functions are significantly influenced by the interaction between the host and the microbiota. The interactions between gut microbiota and cancer are of a complex nature. The critical role that the gut microbiota plays in tumor occurrence, progression, and treatment is not clear despite the already done research. The development of precision medicine and cancer immunotherapy further emphasizes the importance and significance of the question of how the microbiota takes part in cancer development, progression, and treatment. This review summarizes recent literature on the relationship between the gut microbiome and cancer immunology. The findings suggest the existence of a "symbiotic microecosystem" formed by gut microbiota, metabolome, and host immunome that is fundamental for the pathogenesis analysis and the development of therapeutic strategies for cancer.

Human-Hair-Derived Natural Particles as Multifunctional Sunscreen for Effective UV Protection

Excessive ultraviolet (UV) radiation can lead to a series of skin problems. Although commercial sunscreens can protect skin from UV-induced damage to an extent, the side effects caused by such products are still worrisome. Here, inspired by the natural photoprotection effect of human hair, we extracted the multifunctional particles from human hair as sunscreens for UV protection. Both in vitro and in vivo results indicate that hair-derived particles (HDPs) could effectively protect skin from UV radiation. Besides, HDPs retain the antioxidant capability of melanin in hair, which avoids UV-induced oxidative damage. In addition, the unique shape of HDPs can prevent them from penetrating into the skin, thus avoiding potential toxicity. Moreover, owing to their mesoporous structure, the particles can also be used as drug carriers. With the loading of octocrylene, the particles are more effective in blocking UV radiation. This study provides an ingenious tactic for the design and development of sunscreens from a natural substance.

Pathological angiogenesis: mechanisms and therapeutic strategies

In multicellular organisms, angiogenesis, the formation of new blood vessels from pre-existing ones, is an essential process for growth and development. Different mechanisms such as vasculogenesis, sprouting, intussusceptive, and coalescent angiogenesis, as well as vessel co-option, vasculogenic mimicry and lymphangiogenesis, underlie the formation of new vasculature. In many pathological conditions, such as cancer, atherosclerosis, arthritis, psoriasis, endometriosis, obesity and SARS-CoV-2(COVID-19), developmental angiogenic processes are recapitulated, but are often done so without the normal feedback mechanisms that regulate the ordinary spatial and temporal patterns of blood vessel formation. Thus, pathological angiogenesis presents new challenges yet new opportunities for the design of vascular-directed therapies. Here, we provide an overview of recent insights into blood vessel development and highlight novel therapeutic strategies that promote or inhibit the process of angiogenesis to stabilize, reverse, or even halt disease progression. In our review, we will also explore several additional aspects (the angiogenic switch, hypoxia, angiocrine signals, endothelial plasticity, vessel normalization, and endothelial cell anergy) that operate in parallel to canonical angiogenesis mechanisms and speculate how these processes may also be targeted with anti-angiogenic or vascular-directed therapies.

CD4+ T cell-induced inflammatory cell death controls immune-evasive tumours

Most clinically applied cancer immunotherapies rely on the ability of CD8⁺ cytolytic T cells to directly recognize and kill tumour cells^1-3. These strategies are limited by the emergence of major histocompatibility complex (MHC)-deficient tumour cells and the formation of an immunosuppressive tumour microenvironment^4-6. The ability of CD4⁺ effector cells to contribute to antitumour immunity independently of CD8⁺ T cells is increasingly recognized, but strategies to unleash their full potential remain to be identified^7-10. Here, we describe a mechanism whereby a small number of CD4⁺ T cells is sufficient to eradicate MHC-deficient tumours that escape direct CD8⁺ T cell targeting. The CD4⁺ effector T cells preferentially cluster at tumour invasive margins where they interact with MHC-II⁺CD11c⁺ antigen-presenting cells. We show that T helper type 1 cell-directed CD4⁺ T cells and innate immune stimulation reprogramme the tumour-associated myeloid cell network towards interferon-activated antigen-presenting and iNOS-expressing tumouricidal effector phenotypes. Together, CD4⁺ T cells and tumouricidal myeloid cells orchestrate the induction of remote inflammatory cell death that indirectly eradicates interferon-unresponsive and MHC-deficient tumours. These results warrant the clinical exploitation of this ability of CD4⁺ T cells and innate immune stimulators in a strategy to complement the direct cytolytic activity of CD8⁺ T cells and natural killer cells and advance cancer immunotherapies.

Evaluation of the association of chronic inflammation and cancer: Insights and implications

Among the most extensively researched processes in the development and treatment of cancer is inflammatory condition. Although acute inflammation is essential for the wound healing and reconstruction of tissues that have been damaged, chronic inflammation may contribute to the onset and growth of a number of diseases, including cancer. By disrupting the signaling processes of cells, which result in cancer induction, invasion, and development, a variety of inflammatory molecules are linked to the development of cancer. The microenvironment surrounding the tumor is greatly influenced by inflammatory cells and their subsequent secretions, which also contribute significantly to the tumor's growth, survivability, and potential migration. These inflammatory variables have been mentioned in several publications as prospective diagnostic tools for anticipating the onset of cancer. Targeting inflammation with various therapies can reduce the inflammatory response and potentially limit or block the proliferation of cancer cells. The scientific medical literature from the past three decades has been studied to determine how inflammatory chemicals and cell signaling pathways related to cancer invasion and metastasis are related. The current narrative review updates the relevant literature while highlighting the specifics of inflammatory signaling pathways in cancer and their possible therapeutic possibilities.

Deep learning model accurately classifies metastatic tumors from primary tumors based on mutational signatures

Metastatic propagation is the leading cause of death for most cancers. Prediction and elucidation of metastatic process is crucial for the treatment of cancer. Even though somatic mutations have been linked to tumorigenesis and metastasis, it is less explored whether metastatic events can be identified through genomic mutational signatures, which are concise descriptions of the mutational processes. Here, we developed MetaWise, a Deep Neural Network (DNN) model, by applying mutational signatures as input features calculated from Whole-Exome Sequencing (WES) data of TCGA and other metastatic cohorts. This model can accurately classify metastatic tumors from primary tumors and outperform traditional machine learning (ML) models and a deep learning (DL) model, DiaDeL. Signatures of non-coding mutations also have a major impact on the model's performance. SHapley Additive exPlanations (SHAP) and Local Surrogate (LIME) analyses identify several mutational signatures which are directly correlated to metastatic spread in cancers, including APOBEC-mutagenesis, UV-induced signatures, and DNA damage response deficiency signatures.

A PCR protocol to establish standards for routine mycoplasma testing that by design detects over ninety percent of all known mycoplasma species

Mycoplasma infection leads to false and non-reproducible scientific data and poses a risk to human health. Despite strict guidelines calling for regular mycoplasma screening, there is no universal and widely established standard procedure. Here, we describe a reliable and cost-effective PCR method that establishes a universal protocol for mycoplasma testing. The applied strategy utilizes ultra-conserved eukaryotic and mycoplasma sequence primers covering by design 92% of all species in the six orders of the class Mollicutes within the phylum Mycoplasmatota and is applicable to mammalian and many non-mammalian cell types. This method can stratify mycoplasma screening and is suitable as a common standard for routine mycoplasma testing.

The Cross Talk between Cellular Senescence and Melanoma: From Molecular Pathogenesis to Target Therapies

Melanoma is a malignant skin tumor that originates from melanocytes. The pathogenesis of melanoma involves a complex interaction that occurs between environmental factors, ultraviolet (UV)-light damage, and genetic alterations. UV light is the primary driver of the skin aging process and development of melanoma, which can induce reactive oxygen species (ROS) production and the presence of DNA damage in the cells, and results in cell senescence. As cellular senescence plays an important role in the relationship that exists between the skin aging process and the development of melanoma, the present study provides insight into the literature concerning the topic at present and discusses the relationship between skin aging and melanoma, including the mechanisms of cellular senescence that drive melanoma progression, the microenvironment in relation to skin aging and melanoma factors, and the therapeutics concerning melanoma. This review focuses on defining the role of cellular senescence in the process of melanoma carcinogenesis and discusses the targeting of senescent cells through therapeutic approaches, highlighting the areas that require more extensive research in the field.

The journey from melanocytes to melanoma

Over the past decade, melanoma has led the field in new cancer treatments, with impressive gains in on-treatment survival but more modest improvements in overall survival. Melanoma presents heterogeneity and transcriptional plasticity that recapitulates distinct melanocyte developmental states and phenotypes, allowing it to adapt to and eventually escape even the most advanced treatments. Despite remarkable advances in our understanding of melanoma biology and genetics, the melanoma cell of origin is still fiercely debated because both melanocyte stem cells and mature melanocytes can be transformed. Animal models and high-throughput single-cell sequencing approaches have opened new opportunities to address this question. Here, we discuss the melanocytic journey from the neural crest, where they emerge as melanoblasts, to the fully mature pigmented melanocytes resident in several tissues. We describe a new understanding of melanocyte biology and the different melanocyte subpopulations and microenvironments they inhabit, and how this provides unique insights into melanoma initiation and progression. We highlight recent findings on melanoma heterogeneity and transcriptional plasticity and their implications for exciting new research areas and treatment opportunities. The lessons from melanocyte biology reveal how cells that are present to protect us from the damaging effects of ultraviolet radiation reach back to their origins to become a potentially deadly cancer.

Targeting ferroptosis as a cell death pathway in Melanoma: From molecular mechanisms to skin cancer treatment

Melanoma, the most aggressive form of human skin cancer, has been under investigation to reach the most efficient treatment. Surgical resection for early-diagnosed primary melanoma, targeted therapies, and immune checkpoint inhibitors for advanced/metastatic melanoma is the best clinical approach. Ferroptosis, a newly identified iron-dependent cell death pathway, which is morphologically and biochemically different from apoptosis and necrosis, has been reported to be involved in several cancers. Ferroptosis inducers could provide therapeutic options in case of resistance to conventional therapies for advanced/metastatic melanoma. Recently developed ferroptosis inducers, MEK and BRAF inhibitors, miRNAs such as miR-137 and miR-9, and novel strategies for targeting major histocompatibility complex (MHC) class II in melanoma can provide new opportunities for melanoma treatment. Combining ferroptosis inducers with targeted therapies or immune checkpoint inhibitors increases patient response rates. Here we review the mechanisms of ferroptosis and its environmental triggers. We also discuss the pathogenesis and current treatments of melanoma. Moreover, we aim to elucidate the relationship between ferroptosis and melanoma and ferroptosis implications to develop new therapeutic strategies against melanoma.

Glucocorticoid activation by HSD11B1 limits T cell-driven interferon signaling and response to PD-1 blockade in melanoma

BACKGROUND

Immune responses against tumors are subject to negative feedback regulation. Immune checkpoint inhibitors (ICIs) blocking Programmed cell death protein 1 (PD-1), a receptor expressed on T cells, or its ligand PD-L1 have significantly improved the treatment of cancer, in particular malignant melanoma. Nevertheless, responses and durability are variables, suggesting that additional critical negative feedback mechanisms exist and need to be targeted to improve therapeutic efficacy.

METHODS

We used different syngeneic melanoma mouse models and performed PD-1 blockade to identify novel mechanisms of negative immune regulation. Genetic gain-of-function and loss-of-function approaches as well as small molecule inhibitor applications were used for target validation in our melanoma models. We analyzed mouse melanoma tissues from treated and untreated mice by RNA-seq, immunofluorescence and flow cytometry to detect changes in pathway activities and immune cell composition of the tumor microenvironment. We analyzed tissue sections of patients with melanoma by immunohistochemistry as well as publicly available single-cell RNA-seq data and correlated target expression with clinical responses to ICIs.

RESULTS

Here, we identified 11-beta-hydroxysteroid dehydrogenase-1 (HSD11B1), an enzyme that converts inert glucocorticoids into active forms in tissues, as negative feedback mechanism in response to T cell immunotherapies. Glucocorticoids are potent suppressors of immune responses. HSD11B1 was expressed in different cellular compartments of melanomas, most notably myeloid cells but also T cells and melanoma cells. Enforced expression of HSD11B1 in mouse melanomas limited the efficacy of PD-1 blockade, whereas small molecule HSD11B1 inhibitors improved responses in a CD8+ T cell-dependent manner. Mechanistically, HSD11B1 inhibition in combination with PD-1 blockade augmented the production of interferon-γ by T cells. Interferon pathway activation correlated with sensitivity to PD-1 blockade linked to anti-proliferative effects on melanoma cells. Furthermore, high levels of HSD11B1, predominantly expressed by tumor-associated macrophages, were associated with poor responses to ICI therapy in two independent cohorts of patients with advanced melanomas analyzed by different methods (scRNA-seq, immunohistochemistry).

CONCLUSION

As HSD11B1 inhibitors are in the focus of drug development for metabolic diseases, our data suggest a drug repurposing strategy combining HSD11B1 inhibitors with ICIs to improve melanoma immunotherapy. Furthermore, our work also delineated potential caveats emphasizing the need for careful patient stratification.

Tumour mitochondrial DNA mutations drive aerobic glycolysis to enhance checkpoint blockade

The mitochondrial genome encodes essential machinery for respiration and metabolic homeostasis but is paradoxically among the most common targets of somatic mutation in the cancer genome, with truncating mutations in respiratory complex I genes being most over-represented1. While mitochondrial DNA (mtDNA) mutations have been associated with both improved and worsened prognoses in several tumour lineages1-3, whether these mutations are drivers or exert any functional effect on tumour biology remains controversial. Here we discovered that complex I-encoding mtDNA mutations are sufficient to remodel the tumour immune landscape and therapeutic resistance to immune checkpoint blockade. Using mtDNA base editing technology4 we engineered recurrent truncating mutations in the mtDNA-encoded complex I gene, Mt-Nd5, into murine models of melanoma. Mechanistically, these mutations promoted utilisation of pyruvate as a terminal electron acceptor and increased glycolytic flux without major effects on oxygen consumption, driven by an over-reduced NAD pool and NADH shuttling between GAPDH and MDH1, mediating a Warburg-like metabolic shift. In turn, without modifying tumour growth, this altered cancer cell-intrinsic metabolism reshaped the tumour microenvironment in both mice and humans, promoting an anti-tumour immune response characterised by loss of resident neutrophils. This subsequently sensitised tumours bearing high mtDNA mutant heteroplasmy to immune checkpoint blockade, with phenocopy of key metabolic changes being sufficient to mediate this effect. Strikingly, patient lesions bearing >50% mtDNA mutation heteroplasmy also demonstrated a >2.5-fold improved response rate to checkpoint inhibitor blockade. Taken together these data nominate mtDNA mutations as functional regulators of cancer metabolism and tumour biology, with potential for therapeutic exploitation and treatment stratification.

OX40 agonism enhances PD-L1 checkpoint blockade by shifting the cytotoxic T cell differentiation spectrum

Immune checkpoint therapy (ICT) has the power to eradicate cancer, but the mechanisms that determine effective therapy-induced immune responses are not fully understood. Here, using high-dimensional single-cell profiling, we interrogate whether the landscape of T cell states in the peripheral blood predict responses to combinatorial targeting of the OX40 costimulatory and PD-1 inhibitory pathways. Single-cell RNA sequencing and mass cytometry expose systemic and dynamic activation states of therapy-responsive CD4⁺ and CD8⁺ T cells in tumor-bearing mice with expression of distinct natural killer (NK) cell receptors, granzymes, and chemokines/chemokine receptors. Moreover, similar NK cell receptor-expressing CD8⁺ T cells are also detected in the blood of immunotherapy-responsive cancer patients. Targeting the NK cell and chemokine receptors in tumor-bearing mice shows the functional importance of these receptors for therapy-induced anti-tumor immunity. These findings provide a better understanding of ICT and highlight the use and targeting of dynamic biomarkers on T cells to improve cancer immunotherapy.

Effect of neoadjuvant chemotherapy combined with arterial chemoembolization on short-term clinical outcome of locally advanced gastric cancer

BACKGROUND

The purpose of this study was to explore the short-term efficacy and safety of neoadjuvant chemotherapy combined with arterial chemoembolization for locally advanced gastric cancer (LAGC).

METHODS

We retrospectively analyzed the clinical data of 203 patients with LAGC who received neoadjuvant therapy from June 2019 to December 2021. The patients were divided into a neoadjuvant chemotherapy combined with arterial chemoembolization group (combined group, n = 102) and a neoadjuvant chemotherapy group (conventional group, n = 101). The adverse events of chemotherapy, postoperative complications and pathological complete response (pCR) rate were compared between the two groups. Univariate and multivariate analyses were performed to evaluate the potential factors affecting pCR.

RESULTS

A total of 78.8% of the patients were in clinical stage III before neoadjuvant therapy. A total of 52.2% of the patients underwent surgery after receiving two cycles of neoadjuvant therapy. There were 21.2% patients with ≥ grade 3 (CTCAE 4.0) adverse events of chemotherapy and 11.3% patients with Clavien-Dindo classification ≥ grade 3 postoperative complications. Compared with the conventional group, the combination group did not experience an increase in the adverse events of chemotherapy or postoperative complications. The pCR rate in the combined group was significantly higher than that in the conventional group (16.7% vs. 4.95%, P = 0.012). The multivariate analysis showed that arterial chemoembolization, pre-treatment neutrophil-to-lymphocyte ratio (NLR) and pre-treatment platelet-to-lymphocyte ratio (PLR) were independent factors affecting pCR.

CONCLUSION

Neoadjuvant chemotherapy combined with arterial chemoembolization contributed to improving the pCR rate of LAGC patients. Arterial chemoembolization, pre-treatment NLR and pre-treatment PLR were also predictors of pCR.