Therapeutic targeting of tumor growth and angiogenesis with a novel anti-S100A4 monoclonal antibody

Genistein Improves the Cytotoxic, Apoptotic, and Oxidative-Stress-Inducing Properties of Doxorubicin in SK-MEL-28 Cancer Cells

Background and Objectives: Cutaneous melanoma (CM) poses a continuous challenge in oncology due to the developing resistance to available treatments. Doxorubicin (DOX) is noted as one of the most effective chemotherapeutics, although associated toxicity and resistance limit its use in CM treatment. Consequently, DOX has become a promising candidate for combination therapies targeting this neoplasm. Genistein (GEN) gathered significant attention due to its anti-neoplastic properties and ability to enhance the effects of DOX against several cancers, yet this association remains underexplored in CM. Therefore, this study investigated the combination therapy regimen comprising GEN and DOX in terms of anti-melanoma activity and safety profile. Materials and Methods: The in vitro experiments were performed on SK-MEL-28 and HaCaT cells. Cell viability was determined using MTT assay. Cell morphology and confluence were inspected microscopically. Nuclear and cytoskeletal aspects were assessed via immunofluorescence. Apoptosis and oxidative stress were quantified through caspase activity and intracellular reactive oxygen species (ROS) production, respectively. The irritant effect was evaluated on the chorioallantoic membrane. Results: The results revealed that the combination of GEN 10 µM with DOX (0.5 and 1 µM) provided augmented cytotoxic events (e.g., reduced cell viability, altered cell morphology and confluence, apoptotic-like impairments in nuclear shape and cytoskeletal network, increased caspases-3/7 and -9 activity, and elevated ROS) in SK-MEL-28 cells, compared to individual treatments, and exerted a strong synergistic interaction. Simultaneously, GEN 10 µM efficiently surpassed the toxic effects (e.g., viability and confluence loss, hypertrophy, and cytoskeletal condensation) of DOX (0.5 and 1 µM) in HaCaT cells. In ovo, GEN 10 µM + DOX 1 µM treatment was classified as non-irritant. Conclusions: These findings stand as one of the first contributions revealing the beneficial therapeutic interplay between GEN and DOX at physiologically achievable concentrations that resulted in elevated anti-tumor properties in CM cells and alleviated toxicity in keratinocytes.

Extracellular vesicles modulate integrin signaling and subcellular energetics to promote pulmonary lymphangioleiomyomatosis metastasis

Pulmonary lymphangioleiomyomatosis (LAM) is metastatic sarcoma but mechanisms of LAM metastasis are unknown. Extracellular vesicles (EV) regulate cancer metastasis but their roles in LAM have not yet been thoroughly investigated. Here, we report the discovery of distinct LAM-EV subtypes derived from primary tumor or metastasizing LAM cells that promote LAM metastasis through ITGα6/β1-c-Src-FAK signaling, triggered by shuttling ATP synthesis to cell pseudopodia or the activation of integrin adhesion complex, respectively. This signaling leads to increased LAM cell migration, invasiveness, and stemness and regulates metastable (hybrid) phenotypes that are all pivotal for metastasis. Mouse models corroborate in vitro data by demonstrating a significant increase in metastatic burden upon the exposure to EV through distinct mechanisms involving either lung resident fibroblasts or metalloproteinases' activation that are EV subtype dependent. The clinical relevance of these findings is underscored by increased EV biogenies in LAM patients and the enrichment of these EV cargo with lung tropic integrins and metalloproteinases. These findings establish EV as novel therapeutic target in LAM, warranting the future clinical studies.

Targeting of TAMs: can we be more clever than cancer cells?

АBSTRACT: With increasing incidence and geography, cancer is one of the leading causes of death, reduced quality of life and disability worldwide. Principal progress in the development of new anticancer therapies, in improving the efficiency of immunotherapeutic tools, and in the personification of conventional therapies needs to consider cancer-specific and patient-specific programming of innate immunity. Intratumoral TAMs and their precursors, resident macrophages and monocytes, are principal regulators of tumor progression and therapy resistance. Our review summarizes the accumulated evidence for the subpopulations of TAMs and their increasing number of biomarkers, indicating their predictive value for the clinical parameters of carcinogenesis and therapy resistance, with a focus on solid cancers of non-infectious etiology. We present the state-of-the-art knowledge about the tumor-supporting functions of TAMs at all stages of tumor progression and highlight biomarkers, recently identified by single-cell and spatial analytical methods, that discriminate between tumor-promoting and tumor-inhibiting TAMs, where both subtypes express a combination of prototype M1 and M2 genes. Our review focuses on novel mechanisms involved in the crosstalk among epigenetic, signaling, transcriptional and metabolic pathways in TAMs. Particular attention has been given to the recently identified link between cancer cell metabolism and the epigenetic programming of TAMs by histone lactylation, which can be responsible for the unlimited protumoral programming of TAMs. Finally, we explain how TAMs interfere with currently used anticancer therapeutics and summarize the most advanced data from clinical trials, which we divide into four categories: inhibition of TAM survival and differentiation, inhibition of monocyte/TAM recruitment into tumors, functional reprogramming of TAMs, and genetic enhancement of macrophages.

In Vitro Sonodynamic Therapy Using a High Throughput 3D Glioblastoma Spheroid Model with 5-ALA and TMZ Sonosensitizers

Sonodynamic therapy (SDT) administered using low-intensity pulsed ultrasound and sonosensitizers is an emerging, minimally invasive, targeted deep-tissue therapy for solid tumors such as glioblastoma multiforme (GBM). Initial clinical trials show promising outcomes for SDT treatments of GBM. A crucial aspect of SDT is the sonosensitizer that interacts with ultrasound, facilitating energy transfer to the tumor, thus inducing therapeutic efficacy. Current in vitro methods for determining the therapeutic efficacies of sonosensitizers are time-consuming and expensive. A novel high-throughput magnetically printed 3D GBM model is used to overcome this challenge. The hypothesis is that the use of two sonosensitizers, one a chemotherapeutic drug, enhances SDT efficacy through their additive chemical interactions. The GBM model is used to evaluate the effectiveness of two sonosensitizer molecules, 5-aminolevulinic acid (5-ALA) and theU.S. Food and Drug Administration (FDA)-approved chemotherapeutic drug Temozolomide (TMZ). It is confirmed that implement high-throughput GBM models to evaluate sonosensitizer combinations and their efficacies is feasible and, for the first time, show that the combined effect of both sensitizers, 5-ALA and TMZ, is superior for preventing spheroid growth than employing each molecule separately. This finding is relevant for future clinical trials of GBM treatment with SDT.

Extracellular vesicles regulate metastable phenotypes of lymphangioleiomyomatosis cells via shuttling ATP synthesis to pseudopodia and activation of integrin adhesion complexes

Pulmonary lymphangioleiomyomatosis (LAM) is metastatic sarcoma but mechanisms regulating LAM metastasis are unknown. Extracellular vesicle (EV) regulate cancer metastasis but their roles in LAM have not yet been investigated. Here, we report that EV biogenesis is increased in LAM and LAM EV cargo is enriched with lung tropic integrins, metalloproteinases, and cancer stem cell markers. LAM-EV increase LAM cell migration and invasion via the ITGα6/β1-c-Src-FAK-AKT axis. Metastable (hybrid) phenotypes of LAM metastasizing cells, pivotal for metastasis, are regulated by EV from primary tumor or metastasizing LAM cells via shuttling ATP synthesis to cell pseudopodia or activation of integrin adhesion complex, respectively. In mouse models of LAM, LAM-EV increase lung metastatic burden through mechanisms involving lung extracellular matrix remodeling. Collectively, these data provide evidence for the role of EV in promoting LAM lung metastasis and identify novel EV-dependent mechanisms regulating metastable phenotypes of tumor cells. Clinical impact of research is that it establishes LAM pathway as novel target for LAM therapy.

Assessing the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica against AMJ13 and SK-GT-4 human cancer cell lines

Background: Breast and esophageal cancer are the most aggressive and prominent causes of death worldwide. In addition, these cancers showed resistance to current chemotherapy regimens with limited success rates and fatal outcomes. Recently many studies reported the significant cytotoxic effects of phenolic and terpene fractions extracted from various Prunus species against different cancer cell lines. As a result, it has a good chance to be tested as a complement or replacement for standard chemotherapies. Methods: The study aimed to evaluate the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica on breast (AMJ13) and esophageal (SK-GT-4) cancer cell lines by using the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide). Analysis using the Chou-Talalay method was performed to assess the synergistic effect between the extracted fractions and chemotherapeutic agent (docetaxel). Moreover, high-performance liquid chromatography (HPLC) analysis was conducted for the quantitative determination of different bioactive molecules of both phenolic and terpene fractions in the extract. Results: According to the findings, the treatment modalities significantly decreased cancer cell viability of AMJ13 and SK-GT-4 and had insignificant cytotoxicity on the normal cells (normal human fibroblast cell line) (all less than 50% cytotoxicity). Analysis with Chou-Talalay showed a strong synergism with docetaxel on both cancer cell lines (higher cytotoxicity even in low concentrations) and failed to induce cytotoxicity on the normal cells. Important flavonoid glycosides and terpenoids were detected by HPLC, in particularly, ferulic acid, catechin, chlorogenic acid, β-sitosterol, and campesterol. Conclusions: In conclusion, the extracted fractions selectively inhibited the proliferation of both cancer cell lines and showed minimal cytotoxicity on normal cells. These fractions could be naturally derived drugs for treating breast and esophageal cancers.

Prevention of Brain Metastases: A New Frontier

This review discusses the topic of prevention of brain metastases from the most frequent solid tumor types, i.e., lung cancer, breast cancer and melanoma. Within each tumor type, the risk of brain metastasis is related to disease status and molecular subtype (i.e., EGFR-mutant non-small cell lung cancer, HER2-positive and triple-negative breast cancer, BRAF and NRAF-mutant melanoma). Prophylactic cranial irradiation is the standard of care in patients in small cell lung cancer responsive to chemotherapy but at the price of late neurocognitive decline. More recently, several molecular agents with the capability to target molecular alterations driving tumor growth have proven as effective in the prevention of secondary relapse into the brain in clinical trials. This is the case for EGFR-mutant or ALK-rearranged non-small cell lung cancer inhibitors, tucatinib and trastuzumab-deruxtecan for HER2-positive breast cancer and BRAF inhibitors for melanoma. The need for screening with an MRI in asymptomatic patients at risk of brain metastases is emphasized.

Expanding a precision medicine platform for malignant peripheral nerve sheath tumors: New patient-derived orthotopic xenografts, cell lines and tumor entities

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft-tissue sarcomas with a poor survival rate, presenting either sporadically or in the context of neurofibromatosis type 1 (NF1). The histological diagnosis of MPNSTs can be challenging, with different tumors exhibiting great histological and marker expression overlap. This heterogeneity could be partly responsible for the observed disparity in treatment response due to the inherent diversity of the preclinical models used. For several years, our group has been generating a large patient-derived orthotopic xenograft (PDOX) MPNST platform for identifying new precision medicine treatments. Herein, we describe the expansion of this platform using six primary tumors clinically diagnosed as MPNSTs, from which we obtained six additional PDOX mouse models and three cell lines, thus generating three pairs of in vitro-in vivo models. We extensively characterized these tumors and derived preclinical models, including genomic, epigenomic, and histological analyses. Tumors were reclassified after these analyses: three remained as MPNSTs (two being classic MPNSTs), one was a melanoma, another was a neurotrophic tyrosine receptor kinase (NTRK)-rearranged spindle cell neoplasm, and, finally, the last was an unclassifiable tumor bearing neurofibromin-2 (NF2) inactivation, a neuroblastoma RAS viral oncogene homolog (NRAS) oncogenic mutation, and a SWI/SNF-related matrix-associated actin-dependent regulator of chromatin (SMARCA4) heterozygous truncated variant. New cell lines and PDOXs faithfully recapitulated histology, marker expression, and genomic characteristics of the primary tumors. The diversity in tumor identity and their specific associated genomic alterations impacted treatment responses obtained when we used the new cell lines for testing compounds against known altered pathways in MPNSTs. In summary, we present here an extension of our MPNST precision medicine platform, with new PDOXs and cell lines, including tumor entities confounded as MPNSTs in a real clinical scenario. This platform may constitute a useful tool for obtaining correct preclinical information to guide MPNST clinical trials.

Nε-(1-Carboxymethyl)-L-lysine/RAGE Signaling Drives Metastasis and Cancer Stemness through ERK/NFκB axis in Osteosarcoma

Osteosarcoma is an extremely aggressive bone cancer with poor prognosis. Nε-(1-Carboxymethyl)-L-lysine (CML), an advanced glycation end product (AGE), can link to cancer progression, tumorigenesis and metastasis, although the underlying mechanism remains unclear. The role of CML in osteosarcoma progression is still unclear. We hypothesized that CML could promote migration, invasion, and stemness in osteosarcoma cells. CML and its receptor (RAGE; receptor for AGE) were higher expressed at advanced stages in human osteosarcoma tissues. In mouse models, which streptozotocin was administered to induce CML accumulation in the body, the subcutaneous tumor growth was not affected, but the tumor metastasis using tail vein injection model was enhanced. In cell models (MG63 and U2OS cells), CML enhanced tumor sphere formation and acquisition of cancer stem cell characteristics, induced migration and invasion abilities, as well as triggered the epithelial-mesenchymal transition process, which were associated with RAGE expression and activation of downstream signaling pathways, especially the ERK/NFκB pathway. RAGE inhibition elicited CML-induced cell migration, invasion, and stemness through RAGE-mediated ERK/NFκB pathway. These results revealed a crucial role for CML in driving stemness and metastasis in osteosarcoma. These findings uncover a potential CML/RAGE connection and mechanism to osteosarcoma progression and set the stage for further investigation.

Enhancement of the therapeutic efficacy of the MAP regimen using thiamine pyrophosphate-decorated albumin nanoclusters in osteosarcoma treatment

Recent studies on osteosarcoma regimens have mainly focused on modifying the combination of antineoplastic agents rather than enhancing the therapeutic efficacy of each component. Here, an albumin nanocluster (NC)-assisted methotrexate (MTX), doxorubicin (DOX), and cisplatin (MAP) regimen with improved antitumor efficacy is presented. Human serum albumin (HSA) is decorated with thiamine pyrophosphate (TPP) to increase the affinity to the bone tumor microenvironment (TME). MTX or DOX (hydrophobic MAP components) is adsorbed to HSA-TPP via hydrophobic interactions. MTX- or DOX-adsorbed HSA-TPP NCs exhibit 20.8- and 1.64-fold higher binding affinity to hydroxyapatite, respectively, than corresponding HSA NCs, suggesting improved targeting ability to the bone TME via TPP decoration. A modified MAP regimen consisting of MTX- or DOX-adsorbed HSA-TPP NCs and free cisplatin displays a higher synergistic anticancer effect in HOS/MNNG human osteosarcoma cells than conventional MAP. TPP-decorated NCs show 1.53-fold higher tumor accumulation than unmodified NCs in an orthotopic osteosarcoma mouse model, indicating increased bone tumor distribution. As a result, the modified regimen more significantly suppresses tumor growth in vivo than solution-based conventional MAP, suggesting that HSA-TPP NC-assisted MAP may be a promising strategy for osteosarcoma treatment.

Assessing the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica on AMJ13 and SK-GT-4 human cancer cell lines

Background: Breast and esophageal cancer are the most aggressive and prominent causes of death worldwide. In addition, these cancers showed resistance to current chemotherapy regimens with limited success rates and fatal outcomes. Recently many studies reported the significant cytotoxic effects of phenolic and terpene fractions extracted from various Prunus species against different cancer cell lines. As a result, it has a good chance to be tested as a complement or replacement for standard chemotherapies. Methods: The study aimed to evaluate the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica on breast (AMJ13) and esophageal (SK-GT-4) cancer cell lines by using the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide). Analysis using the Chou-Talalay method was performed to assess the synergistic effect between the extracted fractions and chemotherapeutic agent (docetaxel). Moreover, high-performance liquid chromatography (HPLC) analysis was conducted for the quantitative determination of different bioactive molecules of both phenolic and terpene fractions in the extract. Results: According to the findings, the treatment modalities significantly decreased cancer cell viability of AMJ13 and SK-GT-4 and had insignificant cytotoxicity on the normal cells (normal human fibroblast cell line) (all less than 50% cytotoxicity). Analysis with Chou-Talalay showed a strong synergism with docetaxel on both cancer cell lines (higher cytotoxicity even in low concentrations) and failed to induce cytotoxicity on the normal cells. Important flavonoid glycosides and terpenoids were detected by HPLC, in particularly, ferulic acid, catechin, chlorogenic acid, β-sitosterol, and campesterol. Conclusions: In conclusion, the extracted fractions selectively inhibited the proliferation of both cancer cell lines and showed minimal cytotoxicity on normal cells. These fractions could be naturally derived drugs for treating breast and esophageal cancers.

Assessing the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica on AMJ13 and SK-GT-4 human cancer cell lines

Background: Breast and esophageal cancer are the most aggressive and prominent causes of death worldwide. In addition, these cancers showed resistance to current chemotherapy regimens with limited success rates and fatal outcomes. Recently many studies reported the significant cytotoxic effects of phenolic and terpene fractions extracted from various Prunus species against different cancer cell lines. As a result, it has a good chance to be tested as a complement or replacement for standard chemotherapies. Methods: The study aimed to evaluate the cytotoxicity of phenolic and terpene fractions extracted from Iraqi Prunus arabica on breast (AMJ13) and esophageal (SK-GT-4) cancer cell lines by using the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide). Analysis using the Chou-Talalay method was performed to assess the synergistic effect between the extracted fractions and chemotherapeutic agent (docetaxel). Moreover, high-performance liquid chromatography (HPLC) analysis was conducted for the quantitative determination of different bioactive molecules of both phenolic and terpene fractions in the extract. Results: According to the findings, the treatment modalities significantly decreased cancer cell viability of AMJ13 and SK-GT-4 and had insignificant cytotoxicity on the normal cells (normal human fibroblast cell line) (all less than 50% cytotoxicity). Analysis with Chou-Talalay showed a strong synergism with docetaxel on both cancer cell lines (higher cytotoxicity even in low concentrations) and failed to induce cytotoxicity on the normal cells. Important flavonoid glycosides and terpenoids were detected by HPLC, in particularly, ferulic acid, catechin, chlorogenic acid, β-sitosterol, and campesterol. Conclusions: In conclusion, the extracted fractions selectively inhibited the proliferation of both cancer cell lines and showed minimal cytotoxicity on normal cells. These fractions could be naturally derived drugs for treating breast and esophageal cancers.

RAGE Inhibitors for Targeted Therapy of Cancer: A Comprehensive Review

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin family that is overexpressed in several cancers. RAGE is highly expressed in the lung, and its expression increases proportionally at the site of inflammation. This receptor can bind a variety of ligands, including advanced glycation end products, high mobility group box 1, S100 proteins, adhesion molecules, complement components, advanced lipoxidation end products, lipopolysaccharides, and other molecules that mediate cellular responses related to acute and chronic inflammation. RAGE serves as an important node for the initiation and stimulation of cell stress and growth signaling mechanisms that promote carcinogenesis, tumor propagation, and metastatic potential. In this review, we discuss different aspects of RAGE and its prominent ligands implicated in cancer pathogenesis and describe current findings that provide insights into the significant role played by RAGE in cancer. Cancer development can be hindered by inhibiting the interaction of RAGE with its ligands, and this could provide an effective strategy for cancer treatment.

iTRAQ Proteomics Identified the Potential Biomarkers of Coronary Artery Lesion in Kawasaki Disease and In Vitro Studies Demonstrated That S100A4 Treatment Made HCAECs More Susceptible to Neutrophil Infiltration

Coronary artery lesions (CAL) are a major complication of Kawasaki disease (KD). The early prediction of CAL enables the medical personnel to apply adequate medical intervention. We collected the serum samples from the KD patients with CAL (n = 32) and those without CAL (n = 31), followed by a global screening with isobaric tagging for relative and absolute quantification (iTRAQ) technology and specific validation with an enzyme-linked immunosorbent assay (ELISA). iTRAQ identified 846 proteins in total in the serum samples, and four candidate proteins related to CAL were selected for ELISA validation as follows: Protein S100-A4 (S100A4), Catalase (CAT), Folate receptor gamma (FOLR3), and Galectin 10 (CLC). ELISA validation showed that the S100A4 level was significantly higher in KD patients with CAL than in those without CAL (225.2 ± 209.5 vs. 143.3 ± 83 pg/mL, p < 0.05). In addition, KD patients with CAL had a significantly lower CAT level than those without CAL (1.6 ± 1.5 vs. 2.7 ± 2.3 ng/mL, p < 0.05). Next, we found that S100A4 treatment on human coronary artery endothelial cells (HCAECs) reduced the abundance of cell junction proteins, which promoted the migration of HCAECs. Further assays also demonstrated that S100A4 treatment enhanced the permeability of the endothelial layer. These results concluded that S100A4 treatment resulted in an incompact endothelial layer and made HCAECs more susceptible to in vitro neutrophil infiltration. In addition, both upregulated S100A4 and downregulated CAT increased the risk of CAL in KD. Further in vitro study implied that S100A4 could be a potential therapeutic target for CAL in KD.

S100 Proteins in Fatty Liver Disease and Hepatocellular Carcinoma

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent and slow progressing hepatic pathology characterized by different stages of increasing severity which can ultimately give rise to the development of hepatocellular carcinoma (HCC). Besides drastic lifestyle changes, few drugs are effective to some extent alleviate NAFLD and HCC remains a poorly curable cancer. Among the deregulated molecular mechanisms promoting NAFLD and HCC, several members of the S100 proteins family appear to play an important role in the development of hepatic steatosis, non-alcoholic steatohepatitis (NASH) and HCC. Specific members of this Ca²⁺-binding protein family are indeed significantly overexpressed in either parenchymal or non-parenchymal liver cells, where they exert pleiotropic pathological functions driving NAFLD/NASH to severe stages and/or cancer development. The aberrant activity of S100 specific isoforms has also been reported to drive malignancy in liver cancers. Herein, we discuss the implication of several key members of this family, e.g., S100A4, S100A6, S100A8, S100A9 and S100A11, in NAFLD and HCC, with a particular focus on their intracellular versus extracellular functions in different hepatic cell types. Their clinical relevance as non-invasive diagnostic/prognostic biomarkers for the different stages of NAFLD and HCC, or their pharmacological targeting for therapeutic purpose, is further debated.

Calbindin S100A16 Promotes Renal Cell Carcinoma Progression and Angiogenesis via the VEGF/VEGFR2 Signaling Pathway

Purpose

Recent research has indicated that the calcium-binding protein S100A16 promotes carcinogenesis and tumor growth in several forms of cancer. The objective of this study was to examine the relationship between S100A16 and renal cell cancer.

Methods

By using The Cancer Genome Atlas (TCGA) database, the differentially expressed gene S100A16 was identified, and its appearance and link to the prognosis of persons with renal cancer were confirmed. Cox regression was used in multivariate analysis, and a nomogram was developed for internal validation. The correlation between S100A16 and immune cells was analyzed in the TIMER database. Moreover, the potential mechanism of action was investigated utilizing GO and KEGG enrichment analyses. Proliferation, migration, and angiogenesis were investigated in vitro, and the involvement of S100A16 in the undesirable biological events of renal cell carcinoma (RCC) was further explored.

Results

S100A16 was the differentially expressed molecule identified through database screening. Malignant tissues showed higher S100A16 expression than noncancerous tissues, and S100A16 expression was mostly localized in the cytoplasm. According to the TCGA and KM-plotter datasets, patients with RCC and low S100A16 expression had superior OS, PFI, and DSS. The C-index of the nomogram was 0.754 (0.726–0.782), and the accuracy of the prediction model was high. The TIMER database shows that the expression of S100A16 is associated with immune infiltration and may play an important role in promoting tumor cell immune escape in the RCC tumor microenvironment. S100A16 may influence the biological processes of RCC via the VEGF/VEGFR2 signaling route and PI3K-Akt signaling pathway and through P53 alteration and cell cycle according to the gene enrichment technique. In vitro cytological experiments demonstrated that S100A16 knockdown can inhibit the proliferation and migration of renal cancer cells and the expression levels of VEGF, VEGFR2, and phosphorylated AKT within renal cancer cells, thereby inhibiting angiogenesis in renal cancer cells and resulting in a poor prognosis of RCC.

Conclusion

A decrease in S100A16 expression may dramatically increase the OS, PFI, and DSS of patients with RCC and may thus be used as a biomarker for predicting RCC. It may be associated with the immune infiltration of RCC and play a crucial role in the immune evasion of tumor cells within the RCC microenvironment. Intervention of s100a16 can promote the progression and angiogenesis of renal cell carcinoma through the VEGF/VEGFR2 signal transduction pathway and lead to poor prognosis of renal cell carcinoma. These findings suggest a potential target for the development of anticancer strategies for renal cancer.

A High-Throughput Screening Platform Identifies Novel Combination Treatments for Malignant Peripheral Nerve Sheath Tumors

Malignant peripheral nerve sheath tumors (MPNST) are soft-tissue sarcomas that are the leading cause of mortality in patients with Neurofibromatosis type 1 (NF1). Single chemotherapeutic agents have shown response rates ranging from 18% to 44% in clinical trials, so there is still a high medical need to identify chemotherapeutic combination treatments that improve clinical prognosis and outcome. We screened a collection of compounds from the NCATS Mechanism Interrogation PlatE (MIPE) library in three MPNST cell lines, using cell viability and apoptosis assays. We then tested whether compounds that were active as single agents were synergistic when screened as pairwise combinations. Synergistic combinations in vitro were further evaluated in patient-derived orthotopic xenograft/orthoxenograft (PDOX) athymic models engrafted with primary MPNST matching with their paired primary-derived cell line where synergism was observed. The high-throughput screening identified 21 synergistic combinations, from which four exhibited potent synergies in a broad panel of MPNST cell lines. One of the combinations, MK-1775 with Doxorubicin, significantly reduced tumor growth in a sporadic PDOX model (MPNST-SP-01; sevenfold) and in an NF1-PDOX model (MPNST-NF1-09; fourfold) and presented greater effects in TP53 mutated MPNST cell lines. The other three combinations, all involving Panobinostat (combined with NVP-BGT226, Torin 2, or Carfilzomib), did not reduce the tumor volume in vivo at noncytotoxic doses. Our results support the utility of our screening platform of in vitro and in vivo models to explore new therapeutic approaches for MPNSTs and identified that combination MK-1775 with Doxorubicin could be a good pharmacologic option for the treatment of these tumors.

Gambogic Acid and Piperine Synergistically Induce Apoptosis in Human Cholangiocarcinoma Cell via Caspase and Mitochondria-Mediated Pathway

Most cholangiocarcinoma (CCA) patients undergo chemotherapy as a therapeutic approach due to the disease's frequently late diagnosis. However, because CCA is resistant to currently available treatments, the prognosis for this cancer is still quite poor. Combination therapy has emerged as a novel and promising strategy in cancer treatment, as monotherapy frequently results in tumor recurrence and drug resistance. Gambogic acid has been shown to have a synergism with other compounds in combating certain cancer cells. Moreover, piperine has been shown to improve the efficacy of numerous chemotherapy drugs and other anticancer natural substances. However, no research has been done on the combination of these two compounds in the treatment of bile duct cancer. In this study, the cytotoxic activity was determined by using the MTT assay, and then, the combined effect was assessed by using the combination index (CI). We found that the combination of gambogic acid and piperine inhibited cell viability more effectively than either treatment alone, and it also demonstrated a synergistically cytotoxic effect against CCA cells. Interestingly, the findings allowed the use of lower concentrations of gambogic acid in cancer treatment when combined with piperine, which could reduce its adverse effect on normal cholangiocytes. Furthermore, the combination of the two compounds increased CCA cell death by inducing apoptosis via both the extrinsic and intrinsic or mitochondria-mediated pathways, as determined by caspase-3, -8, and -9 activity and the reduction of mitochondrial transmembrane potential (ΔΨm). It is possible that the use of these two natural compounds together could be a promising strategy for the treatment of bile duct cancer.

Single-cell analysis of human glioma and immune cells identifies S100A4 as an immunotherapy target

A major rate-limiting step in developing more effective immunotherapies for GBM is our inadequate understanding of the cellular complexity and the molecular heterogeneity of immune infiltrates in gliomas. Here, we report an integrated analysis of 201,986 human glioma, immune, and other stromal cells at the single cell level. In doing so, we discover extensive spatial and molecular heterogeneity in immune infiltrates. We identify molecular signatures for nine distinct myeloid cell subtypes, of which five are independent prognostic indicators of glioma patient survival. Furthermore, we identify S100A4 as a regulator of immune suppressive T and myeloid cells in GBM and demonstrate that deleting S100a4 in non-cancer cells is sufficient to reprogram the immune landscape and significantly improve survival. This study provides insights into spatial, molecular, and functional heterogeneity of glioma and glioma-associated immune cells and demonstrates the utility of this dataset for discovering therapeutic targets for this poorly immunogenic cancer.

Myeloid cell interferon responses correlate with clearance of SARS-CoV-2

Emergence of mutant SARS-CoV-2 strains associated with an increased risk of COVID-19-related death necessitates better understanding of the early viral dynamics, host responses and immunopathology. Single cell RNAseq (scRNAseq) allows for the study of individual cells, uncovering heterogeneous and variable responses to environment, infection and inflammation. While studies have reported immune profiling using scRNAseq in terminal human COVID-19 patients, performing longitudinal immune cell dynamics in humans is challenging. Macaques are a suitable model of SARS-CoV-2 infection. Our longitudinal scRNAseq of bronchoalveolar lavage (BAL) cell suspensions from young rhesus macaques infected with SARS-CoV-2 (n = 6) demonstrates dynamic changes in transcriptional landscape 3 days post- SARS-CoV-2-infection (3dpi; peak viremia), relative to 14-17dpi (recovery phase) and pre-infection (baseline) showing accumulation of distinct populations of both macrophages and T-lymphocytes expressing strong interferon-driven inflammatory gene signature at 3dpi. Type I interferon response is induced in the plasmacytoid dendritic cells with appearance of a distinct HLADR+CD68+CD163+SIGLEC1+ macrophage population exhibiting higher angiotensin-converting enzyme 2 (ACE2) expression. These macrophages are significantly enriched in the lungs of macaques at 3dpi and harbor SARS-CoV-2 while expressing a strong interferon-driven innate anti-viral gene signature. The accumulation of these responses correlated with decline in viremia and recovery.

Myeloid cell interferon responses correlate with clearance of SARS-CoV-2

The emergence of mutant SARS-CoV-2 strains associated with an increased risk of COVID-19-related death necessitates better understanding of the early viral dynamics, host responses and immunopathology. While studies have reported immune profiling using single cell RNA sequencing in terminal human COVID-19 patients, performing longitudinal immune cell dynamics in humans is challenging. Macaques are a suitable model of SARS-CoV-2 infection. We performed longitudinal single-cell RNA sequencing of bronchoalveolar lavage (BAL) cell suspensions from adult rhesus macaques infected with SARS-CoV-2 (n=6) to delineate the early dynamics of immune cells changes. The bronchoalveolar compartment exhibited dynamic changes in transcriptional landscape 3 days post- SARS-CoV-2-infection (3dpi) (peak viremia), relative to 14-17dpi (recovery phase) and pre-infection (baseline). We observed the accumulation of distinct populations of both macrophages and T-lymphocytes expressing strong interferon-driven inflammatory gene signature at 3dpi. Type I IFN response was highly induced in the plasmacytoid dendritic cells. The presence of a distinct HLADR+CD68+CD163+SIGLEC1+ macrophage population exhibiting higher angiotensin converting enzyme 2 (ACE2) expression was also observed. These macrophages were significantly recruited to the lungs of macaques at 3dpi and harbored SARS-CoV-2, while expressing a strong interferon-driven innate anti-viral gene signature. The accumulation of these responses correlated with decline in viremia and recovery. The recruitment of a myeloid cell-mediated Type I IFN response is associated with the rapid clearance of SARS-CoV-2 infection in macaques.

New Angiogenic Regulators Produced by TAMs: Perspective for Targeting Tumor Angiogenesis

Simple Summary

Since the targeting of a single pro-angiogenic factor fails to improve oncological disease outcome, significant efforts have been made to identify new pro-angiogenic factors that could compensate for the deficiency of current therapy or act independently as single drugs. Our review aims to present the state-of-the art for well-known and recently described factors produced by macrophages that induce and regulate angiogenesis. A number of positive and negative regulators of angiogenesis in the tumor microenvironment are produced by tumor-associated macrophages (TAMs). Accumulating evidence has indicated that, apart from the well-known angiogenic factors, there are plenty of novel angiogenesis-regulating proteins that belong to different classes. We summarize the data regarding the direct or indirect mechanisms of the interaction of these factors with endothelial cells during angiogenesis. We highlight the recent findings that explain the limitations in the efficiency of current anti-angiogenic therapy approaches.

Abstract

Angiogenesis is crucial to the supply of a growing tumor with nutrition and oxygen. Inhibition of angiogenesis is one of the main treatment strategies for colorectal, lung, breast, renal, and other solid cancers. However, currently applied drugs that target VEGF or receptor tyrosine kinases have limited efficiency, which raises a question concerning the mechanism of patient resistance to the already developed drugs. Tumor-associated macrophages (TAMs) were identified in the animal tumor models as a key inducer of the angiogenic switch. TAMs represent a potent source not only for VEGF, but also for a number of other pro-angiogenic factors. Our review provides information about the activity of secreted regulators of angiogenesis produced by TAMs. They include members of SEMA and S100A families, chitinase-like proteins, osteopontin, and SPARC. The COX-2, Tie2, and other factors that control the pro-angiogenic activity of TAMs are also discussed. We highlight how these recent findings explain the limitations in the efficiency of current anti-angiogenic therapy. Additionally, we describe genetic and posttranscriptional mechanisms that control the expression of factors regulating angiogenesis. Finally, we present prospects for the complex targeting of the pro-angiogenic activity of TAMs.

Targeted silencing of TEM8 suppresses non‑small cell lung cancer tumor growth via the ERK/Bcl‑2 signaling pathway

Non-small cell lung cancer (NSCLC) is one of the most common malignancies with high rates of mortality. Although great progress has been made with the development of novel immunotherapies and targeted therapeutic strategies, the 5-year total survival rate of lung cancer has remained unchanged over the past few decades. Therefore, more effective therapeutics are urgently needed. Tumor endothelial marker 8 (TEM8) is an integrin-like cell surface transmembrane protein that has been demonstrated to be upregulated in numerous cancer types and previously showed promise for targeted cancer therapy. However, the role of TEM8 in NSCLC remains poorly understood. The present study aimed to investigate the effects of silencing TEM8 on expression and regulation of extracellular signal-regulated kinase (ERK)1/2 signaling pathways in NSCLC. In the present study, a lentiviral vector that encoded a short hairpin RNA targeting TEM8 was designed and transfected into Xuanwei Lung Cancer (XWLC)-05 lung cancer cells to silence TEM8 expression. Male BALB/c-nu/nu mice were then given subcutaneous injections in the right dorsal flank with XWLC-05 cells. Microvessel density was measured using an anti-CD34 antibody. The mRNA and protein levels of ERK1/2 and Bcl-2 in XWLC-05 cells or xenograft tumor tissues were detected by reverse transcription-quantitative polymerase chain reaction and western blotting. TEM8 knockdown was found to significantly inhibit tumor growth and conferred an anti-angiogenic ability in vivo. Furthermore, TEM8 knockdown suppressed the expression of Bcl-2 mediated by ERK1/2 activity in XWLC-05 cells or tissues from mice with NSCLC. To conclude, these results suggest that the targeted silencing of TEM8 may serve as an effective method of treating NSCLC.

S100A4 Is Involved in Stimulatory Effects Elicited by the FGF2/FGFR1 Signaling Pathway in Triple-Negative Breast Cancer (TNBC) Cells

Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.

Cold Atmospheric Plasma Increases Temozolomide Sensitivity of Three-Dimensional Glioblastoma Spheroids via Oxidative Stress-Mediated DNA Damage

Simple Summary

Cold atmospheric plasma (CAP) is gaining increasing interest for cancer treatment, for a wide range of cancer types. The studies performed with CAP as a standalone treatment modality serve as evidence that it can also be a suitable candidate for combination therapy. Temozolomide (TMZ) is used as the gold standard drug for glioblastoma treatment, one of the most aggressive malignant brain tumors in adults that remains incurable despite treatment advances. In this study, we explore whether CAP, a cocktail of reactive oxygen and nitrogen species, can amplify the cytotoxic effect on both TMZ-sensitive and TMZ-resistant glioblastoma multiforme (GBM) in three-dimensional tumor-like tissues through inhibiting the glutathione (GSH)/ glutathione peroxidase 4 (GPX4) antioxidant machinery, which can further lead to DNA damage.

Abstract

Glioblastoma multiforme (GBM) is the most frequent and aggressive primary malignant brain tumor in adults. Current standard radiotherapy and adjuvant chemotherapy with the alkylating agent temozolomide (TMZ) yield poor clinical outcome. This is due to the stem-like properties of tumor cells and genetic abnormalities in GBM, which contribute to resistance to TMZ and progression. In this study, we used cold atmospheric plasma (CAP) to enhance the sensitivity to TMZ through inhibition of antioxidant signaling (linked to TMZ resistance). We demonstrate that CAP indeed enhances the cytotoxicity of TMZ by targeting the antioxidant specific glutathione (GSH)/glutathione peroxidase 4 (GPX4) signaling. We optimized the threshold concentration of TMZ on five different GBM cell lines (U251, LN18, LN229, U87-MG and T98G). We combined TMZ with CAP and tested it on both TMZ-sensitive (U251, LN18 and LN229) and TMZ-resistant (U87-MG and T98G) cell lines using two-dimensional cell cultures. Subsequently, we used a three-dimensional spheroid model for the U251 (TMZ-sensitive) and U87-MG and T98G (TMZ-resistant) cells. The sensitivity of TMZ was enhanced, i.e., higher cytotoxicity and spheroid shrinkage was obtained when TMZ and CAP were administered together. We attribute the anticancer properties to the release of intracellular reactive oxygen species, through inhibiting the GSH/GPX4 antioxidant machinery, which can lead to DNA damage. Overall, our findings suggest that the combination of CAP with TMZ is a promising combination therapy to enhance the efficacy of TMZ towards the treatment of GBM spheroids.

Friend or Foe: S100 Proteins in Cancer

S100 proteins are widely expressed small molecular EF-hand calcium-binding proteins of vertebrates, which are involved in numerous cellular processes, such as Ca²⁺ homeostasis, proliferation, apoptosis, differentiation, and inflammation. Although the complex network of S100 signalling is by far not fully deciphered, several S100 family members could be linked to a variety of diseases, such as inflammatory disorders, neurological diseases, and also cancer. The research of the past decades revealed that S100 proteins play a crucial role in the development and progression of many cancer types, such as breast cancer, lung cancer, and melanoma. Hence, S100 family members have also been shown to be promising diagnostic markers and possible novel targets for therapy. However, the current knowledge of S100 proteins is limited and more attention to this unique group of proteins is needed. Therefore, this review article summarises S100 proteins and their relation in different cancer types, while also providing an overview of novel therapeutic strategies for targeting S100 proteins for cancer treatment.

Role and Mechanisms of RAGE-Ligand Complexes and RAGE-Inhibitors in Cancer Progression

Interactions of the receptor for advanced glycation end product (RAGE) and its ligands in the context of their role in diabetes mellitus, inflammation, and carcinogenesis have been extensively investigated. This review focuses on the role of RAGE-ligands and anti-RAGE drugs capable of controlling cancer progression. Different studies have demonstrated interaction of RAGE with a diverse range of acidic (negatively charged) ligands such as advanced glycation end products (AGEs), high-mobility group box1 (HMGB1), and S100s, and their importance to cancer progression. Some RAGE-ligands displayed effects on anti- and pro-apoptotic proteins through upregulation of the phosphatidylinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), mitogen-activated protein kinases (MAPKs), matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), and nuclear factor kappa B (NF-κB) pathways, while downregulating p53 in cancer progression. In addition, RAGE may undergo ligand-driven multimodal dimerization or oligomerization mediated through self-association of some of its subunits. We conclude our review by proposing possible future lines of study that could result in control of cancer progression through RAGE inhibition.

S100A4 mRNA-protein relationship uncovered by measurement noise reduction

Intrinsic biological fluctuation and/or measurement error can obscure the association of gene expression patterns between RNA and protein levels. Appropriate normalization of reverse-transcription quantitative PCR (RT-qPCR) data can reduce technical noise in transcript measurement, thus uncovering such relationships. The accuracy of gene expression measurement is often challenged in the context of cancer due to the genetic instability and "splicing weakness" involved. Here, we sequenced the poly(A) cancer transcriptome of canine osteosarcoma using mRNA-Seq. Expressed sequences were resolved at the level of two consecutive exons to enable the design of exon-border spanning RT-qPCR assays and ranked for stability based on the coefficient of variation (CV). Using the same template type for RT-qPCR validation, i.e. poly(A) RNA, avoided skewing of stability assessment by circular RNAs (circRNAs) and/or rRNA deregulation. The strength of the relationship between mRNA expression of the tumour marker S100A4 and its proportion score of quantitative immunohistochemistry (qIHC) was introduced as an experimental readout to fine-tune the normalization choice. Together with the essential logit transformation of qIHC scores, this approach reduced the noise of measurement as demonstrated by uncovering a highly significant, strong association between mRNA and protein expressions of S100A4 (Spearman's coefficient ρ = 0.72 (p = 0.006)). KEY MESSAGES: • RNA-seq identifies stable pairs of consecutive exons in a heterogeneous tumour. • Poly(A) RNA templates for RT-qPCR avoid bias from circRNA and rRNA deregulation. • HNRNPL is stably expressed across various cancer tissues and osteosarcoma. • Logit transformed qIHC score better associates with mRNA amount. • Quantification of minor S100A4 mRNA species requires poly(A) RNA templates and dPCR.

Extracellular S100A4 as a key player in fibrotic diseases

Fibrosis is characterized by fibroblast activation, extracellular matrix (ECM) accumulation and infiltration of inflammatory cells that sometimes leads to irreversible organ dysfunction. Considerable evidence now indicates that inflammation plays a critical role in the initiation and progression of organ fibrosis. S100A4 protein, a ubiquitous member of the S100 family, has recently been discovered as a potential factor implicated in fibrotic diseases. S100A4 protein is released at inflammatory site and has a certain biological function to promote cell motility, invasion, ECM remodelling, autophagy and angiogenesis. In addition, extracellular S100A4 is also a potential causation of inflammatory processes and induces the release of cytokines and growth factors under different pathological conditions. Elevated S100A4 level in patients’ serum closely correlates with disease activity in several fibrotic diseases and serves as a useful biomarker for diagnosis and monitoring disease progression. Analyses of knockout mouse models have identified a functional role of extracellular S100A4 protein in fibrotic diseases, suggesting that suppressing its expression, release or function might be a promising therapeutic strategy. This review will focus on the role of extracellular S100A4 as a key regulator of pro‐inflammatory signalling pathways and its relative biological processes involved in the pathogenesis of fibrosis.

Role of S100 proteins in health and disease

The S100 family of proteins contains 25 known members that share a high degree of sequence and structural similarity. However, only a limited number of family members have been characterized in depth, and the roles of other members are likely undervalued. Their importance should not be underestimated however, as S100 family members function to regulate a diverse array of cellular processes including proliferation, differentiation, inflammation, migration and/or invasion, apoptosis, Ca²⁺ homeostasis, and energy metabolism. Here we detail S100 target protein interactions that underpin the mechanistic basis to their function, and discuss potential intervention strategies targeting S100 proteins in both preclinical and clinical situations.

A Potent Autophagy Inhibitor (Lys05) Enhances the Impact of Ionizing Radiation on Human Lung Cancer Cells H1299

Autophagy inhibition through small-molecule inhibitors is one of the approaches to increase the efficiency of radiotherapy in oncological patients. A new inhibitor-Lys05-with the potential to accumulate within lysosomes and to block autophagy was discovered a few years ago. Several studies have addressed its chemosensitizing effects but nothing is known about its impact in the context of ionizing radiation (IR). To describe its role in radiosensitization, we employed radioresistant human non-small cell lung carcinoma cells (H1299, p53-negative). Combined treatment of H1299 cells by Lys05 together with IR decreased cell survival in the clonogenic assay and real-time monitoring of cell growth more than either Lys05 or IR alone. Immunodetection of LC3 and p62/SQSTM1 indicated that autophagy was inhibited, which correlated with increased SQSTM1 and decreased BNIP3 gene expression determined by qRT-PCR. Fluorescence microscopy and flow cytometry uncovered an accumulation of lysosomes. Similarly, transmission electron microscopy demonstrated the accumulation of autophagosomes confirming the ability of Lys05 to potentiate autophagy inhibition in H1299 cells. We report here for the first time that Lys05 could be utilized in combination with IR as a promising future strategy in the eradication of lung cancer cells.

Therapeutic Strategies Targeting Cancer Stem Cells and Their Microenvironment

Cancer stem cells (CSCs) have been demonstrated in a variety of tumors and are thought to act as a clonogenic core for the genesis of new tumor growth. This small subpopulation of cancer cells has been proposed to help drive tumorigenesis, metastasis, recurrence and conventional therapy resistance. CSCs show self-renewal and flexible clonogenic properties and help define specific tumor microenvironments (TME). The interaction between CSCs and TME is thought to function as a dynamic support system that fosters the generation and maintenance of CSCs. Investigation of the interaction between CSCs and the TME is shedding light on the biologic mechanisms underlying the process of tumor malignancy, metastasis, and therapy resistance. We summarize recent advances in CSC biology and their environment, and discuss the challenges and future strategies for targeting this biology as a new therapeutic approach.

Synergistic Effects of Melittin and Plasma Treatment: A Promising Approach for Cancer Therapy

Melittin (MEL), a small peptide component of bee venom, has been reported to exhibit anti-cancer effects in vitro and in vivo. However, its clinical applicability is disputed because of its non-specific cytotoxicity and haemolytic activity in high treatment doses. Plasma-treated phosphate buffered saline solution (PT-PBS), a solution rich in reactive oxygen and nitrogen species (RONS) can disrupt the cell membrane integrity and induce cancer cell death through oxidative stress-mediated pathways. Thus, PT-PBS could be used in combination with MEL to facilitate its access into cancer cells and to reduce the required therapeutic dose. The aim of our study is to determine the reduction of the effective dose of MEL required to eliminate cancer cells by its combination with PT-PBS. For this purpose, we have optimised the MEL threshold concentration and tested the combined treatment of MEL and PT-PBS on A375 melanoma and MCF7 breast cancer cells, using in vitro, in ovo and in silico approaches. We investigated the cytotoxic effect of MEL and PT-PBS alone and in combination to reveal their synergistic cytological effects. To support the in vitro and in ovo experiments, we showed by computer simulations that plasma-induced oxidation of the phospholipid bilayer leads to a decrease of the free energy barrier for translocation of MEL in comparison with the non-oxidized bilayer, which also suggests a synergistic effect of MEL with plasma induced oxidation. Overall, our findings suggest that MEL in combination with PT-PBS can be a promising combinational therapy to circumvent the non-specific toxicity of MEL, which may help for clinical applicability in the future.

The Multifaceted S100A4 Protein in Cancer and Inflammation

The metastasis-promoting S100A4 protein, a member of the S100 family, has recently been discovered as a potent factor implicated in various inflammation-associated diseases. S100A4 is involved in a range of biological functions such as angiogenesis, cell differentiation, apoptosis, motility, and invasion. Moreover, S100A4 is also a potent trigger of inflammatory processes and induces the release of cytokines and growth factors under different pathological conditions.Indeed, the release of S100A4 upon stress and mainly its pro-inflammatory role emerges as the most decisive activity in disease development, such as rheumatoid arthritis (RA), systemic sclerosis (SSc) allergy, psoriasis, and cancer. In the scope of this review, we will focus on the role of S100A4 as a mediator of pro-inflammatory pathways and its associated biological processes involved in the pathogenesis of various human noncommunicable diseases (NCDs) including cancer.

Prognostic and clinicopathological significance of S100A14 expression in cancer patients: A meta-analysis

BACKGROUND

The prognostic significance of S100A14 for survival of cancer patients remains controversial. Therefore, we conducted this meta-analysis to explore the association between S100A14 expression and cancer prognosis.

METHOD

Eligible studies were identified by searching the online databases Pubmed and EMBASE up to August 2018. Odds ratios (ORs) with 95% confidence intervals (CIs) severed as the summarized statistics for clinicopathological assessments and hazard ratios (HRs) with 95% CIs were calculated to clarify the correlation between S100A14 expression and prognosis of different cancers.

RESULTS

A total of 11 studies with 1651 cancer patients were enrolled. The results indicated that S100A14 expression was not significantly associated with overall survival (OS) in total various cancers (HR = 1.54, 95% CI:0.89-2.67, P = .121). Further subgroup analysis stratified by tumor type showed that elevated S100A14 expression was associated with poor OS in breast cancer (HR = 3.66, 95% CI: 1.75-7.62, P < .001) and in ovarian cancer patients (HR = 3.78, 95%CI: 1.63-8.73, P = .002). Interestingly, high S100A14 expression was correlated with poor tumor differentiation (OR = 2.51, 95% CI: 1.52-4.13, P < .001). However, there were no significant correlations between S100A14 expression and other clinicopathologic characteristics. Begg funnel plot and Egger test showed that no publication bias was detected.

CONCLUSIONS

Our meta-analysis suggests that S100A14 overexpression might be a predictive biomarker for poor prognosis in patients with breast cancer and ovarian cancer. Large-scale studies are required to confirm these results.

Cancer-associated fibroblasts in radiotherapy: challenges and new opportunities

Background

Radiotherapy is one of the most important therapeutic strategies for treating cancer. For decades, studies concerning the outcomes of radiotherapy mainly focused on the biological effects of radiation on tumor cells. Recently, we have increasingly recognized that the complex cellular interactions within the tumor microenvironment (TME) are closely related to treatment outcomes.

Main content

As a critical component of the TME, fibroblasts participate in all stages of cancer progression. Fibroblasts are able to tolerate harsh extracellular environments, which are usually fatal to all other cells. They play pivotal roles in determining the treatment response to chemoradiotherapy. Radiotherapy activates the TME networks by inducing cycling hypoxia, modulating immune reaction, and promoting vascular regeneration, inflammation and fibrosis. While a number of studies claim that radiotherapy affects fibroblasts negatively through growth arrest and cell senescence, others argue that exposure to radiation can induce an activated phenotype in fibroblasts. These cells take an active part in constructing the tumor microenvironment by secreting cytokines and degradative enzymes. Current strategies that aim to inhibit activated fibroblasts mainly focus on four aspects: elimination, normalization, paracrine signaling blockade and extracellular matrix inhibition. This review will describe the direct cellular effects of radiotherapy on fibroblasts and the underlying genetic changes. We will also discuss the impact of fibroblasts on cancer cells during radiotherapy and the potential value of targeting fibroblasts to enhance the clinical outcome of radiotherapy.

Conclusion

This review provides good preliminary data to elucidate the biological roles of CAFs in radiotherapy and the clinical value of targeting CAFs as a supplementary treatment to conventional radiotherapy. Further studies to validate this strategy in more physiological models may be required before clinical trial.

Oligomeric S100A4 Is Associated With Monocyte Innate Immune Memory and Bypass of Tolerance to Subsequent Stimulation With Lipopolysaccharides

Objectives: Most DAMPs in inflammatory diseases are TLR2- and TLR4-ligands and according to the current concept, repeated stimuli would result in tolerance. Aims of the study were to verify this assumption, to investigate whether epigenetic effectors are involved and to explore the situation in rheumatoid arthritis (RA).

Methods: A trained immunity (TI) and tolerance protocol was established using peripheral blood monocytes from healthy donors, β-glucan and lipopolysaccharide (LPS). The training or tolerance capacities of RA-relevant DAMPs were tested.

Results: β-Glucan-, oS100A4-, HMBG1-, and HSP90-pretreated monocytes showed increased IL-6 responses to LPS re-stimulation. β-Glucan, oS100A and tenascin C induced training of monocytes to release more TNFα. In comparison to β-glucan, most DAMPs tested induced less TI, with exception of oS100A4. Monocytes exposed to oS100A4 showed increased IL-1β, IL-6, and TNFα in response to LPS, in spite that both stimulate TLR4. RNASEq upon β-glucan or oS100A4 revealed similar changes in chemokines/cytokines and epigenetic effectors; 17 epigenetic effectors correlated with chemokine/cytokine gene expression; PRDM8 was associated with more chemokine and cytokine transcripts. Knockdown of PRDM8 abolished TI induced by oS100A4. In RA, plasma S100A4 correlated with increased CSF2, and increased PRDM8 transcription in RA monocytes was associated with increased plasma CCL5 and IL-6, as well as therapy-resistance.

Conclusion: Bypass of tolerance by DAMPs might be a phenomenon as important as TI, since it could explain how chronic inflammation can be maintained in spite of an environment with multiple TLR2/TLR4-ligands. In RA monocytes, a PRDM8-dependent TI mechanism could be responsible for sustained chemokine/cytokines levels.

S100 proteins as therapeutic targets

The human genome codes for 21 S100 protein family members, which exhibit cell- and tissue-specific expression patterns. Despite sharing a high degree of sequence and structural similarity, the S100 proteins bind a diverse range of protein targets and contribute to a broad array of intracellular and extracellular functions. Consequently, the S100 proteins regulate multiple cellular processes such as proliferation, migration and/or invasion, and differentiation, and play important roles in a variety of cancers, autoimmune diseases, and chronic inflammatory disorders. This review focuses on the development of S100 neutralizing antibodies and small molecule inhibitors and their potential therapeutic use in controlling disease progression and severity.

New Era in the Management of Melanoma Brain Metastases

The remarkable advances in the systemic therapy of metastatic melanoma have now extended the 1-year overall survival rate from 25% to nearing 85%. Systemic treatment in the form of BRAF-targeted therapy and immunotherapy is slowly but surely proving its efficacy in the treatment of metatstatic brain metastases (MBM). Single-agent BRAF inhibitors provide an intracranial response rate of 25% to 40%, whereas the combination of BRAFi/MEKi leads to responses in up to 58%. However, the durability of responses induced by BRAFi/MEKi seems to be even shorter than in extracranial disease. On the other hand, single-agent ipilimumab provides comparable clinical benefit in MBMs as it does in extracranial metastases. Single-agent PD-1 anitbodies induce response rates of approximately 20%, and those responses appear durable. Similarly the combination of CTLA-4+ PD-1 antibodies induces durable responses at an impressive rate of 55% and is safe to administer. Although the local treatment approaches with radiation and surgery remain important and are critically needed in the management of MBM, systemic therapy offers a new dimension that can augment the impact of those therapies and come at a potentially lower cost of neurocognitive impairment. Considerations for combining those modalities are direly needed, in addition to considering novel systemic combinations that target mechanisms specific to MBM. In this report, we will discuss the underlying biology of melanoma brain metastases, the clinical outcomes from recent clinical trials of targeted and immunotherapy, and their impact on clinical practice in the context of existing local therapeutic modalities.

Biomarker panel predicts survival after resection in pancreatic ductal adenocarcinoma: A multi-institutional cohort study

BACKGROUND

Up to 60% of patients who undergo curative-intent pancreatic ductal adenocarcinoma (PDAC) resection experience disease recurrence within six months. We recently published a systematic review of prognostic immunohistochemical biomarkers in PDAC and shortlisted a panel of those reported with the highest level of evidence, including p53, p16, Ca-125, S100A4, FOXC1, EGFR, mesothelin, CD24 and UPAR. This study aims to discover and validate the prognostic significance of a combinatorial panel of tumor biomarkers in patients with resected PDAC.

METHODS

Patients who underwent PDAC resection were included from a single institution discovery cohort and a multi-institutional validation cohort. Tumors in the discovery cohort were stained immunohistochemically for all nine shortlisted biomarkers. Biomarkers significantly associated with overall survival (OS) were reevaluated as a combinatorial panel in both discovery and validation cohorts for its prognostic significance.

RESULTS

224 and 191 patients were included in the discovery and validation cohorts, respectively. In both cohorts, S100A4, Ca-125 and mesothelin expression were associated with shorter OS. In both cohorts, the number of these biomarkers expressed was significantly associated with OS (discovery cohort 36.8 vs. 26.4 vs 16.3 vs 12.8 months, P < 0.001; validation cohort 25.2 vs 18.3 vs 13.6 vs 11.9 months, P = 0.008 for expression of zero, one, two and three biomarkers, respectively). On multivariable analysis, expression of at least one of three biomarkers was independently associated with shorter OS.

CONCLUSION

Combinations of S100A4, Ca-125 and mesothelin expression stratify survival after resection of localized PDAC. Co-expression of all three biomarkers is associated with the poorest prognostic outcome.

Myosin X is required for efficient melanoblast migration and melanoma initiation and metastasis

Myosin X (Myo10), an actin-associated molecular motor, has a clear role in filopodia induction and cell migration in vitro, but its role in vivo in mammals is not well understood. Here, we investigate the role of Myo10 in melanocyte lineage and melanoma induction. We found that Myo10 knockout (Myo10KO) mice exhibit a white spot on their belly caused by reduced melanoblast migration. Myo10KO mice crossed with available mice that conditionally express in melanocytes the BRAFV600E mutation combined with Pten silencing exhibited reduced melanoma development and metastasis, which extended medial survival time. Knockdown of Myo10 (Myo10kd) in B16F1 mouse melanoma cell lines decreased lung colonization after tail-vein injection. Myo10kd also inhibited long protrusion (LP) formation by reducing the transportation of its cargo molecule vasodilator-stimulated phosphoprotein (VASP) to the leading edge of migrating cells. These findings provide the first genetic evidence for the involvement of Myo10 not only in melanoblast migration, but also in melanoma development and metastasis.

A ternary-complex of a suicide gene, a RAGE-binding peptide, and polyethylenimine as a gene delivery system with anti-tumor and anti-angiogenic dual effects in glioblastoma

The receptor for advanced glycation end-products (RAGE) is involved in tumor angiogenesis. Inhibition of RAGE might be an effective anti-angiogenic therapy for cancer. In this study, a cationic RAGE-binding peptide (RBP) was produced as an antagonist of RAGE, and a ternary-complex consisting of RBP, polyethylenimine (2 kDa, PEI2k), and a suicide gene (pHSVtk) was developed as a gene delivery system with dual functions: the anti-tumor effect of pHSVtk and anti-angiogenic effect of RBP. As an antagonist of RAGE, RBP decreased the secretion of vascular-endothelial growth factor (VEGF) in activated macrophages and reduced the tube-formation of endothelial cells in vitro. In in vitro transfection assays, the RBP/PEI2k/plasmid DNA (pDNA) ternary-complex had higher transfection efficiency than the PEI2k/pDNA binary-complex. In an intracranial glioblastoma animal model, the RBP/PEI2k/pHSVtk ternary-complex reduced α-smooth muscle actin expression, suggesting that the complex has an anti-angiogenic effect. In addition, the ternary-complex had higher pHSVtk delivery efficiency than the PEI2k/pHSVtk and PEI25k/pHSVtk binary-complexes in an animal model. As a result, the ternary-complex induced apoptosis and reduced tumor volume more effectively than the PEI2k/pHSVtk and PEI25k/pHSVtk binary-complexes. In conclusion, due to its dual anti-tumor and anti-angiogenesis effects, the RBP/PEI2k/pHSVtk ternary-complex might be an efficient gene delivery system for the treatment of glioblastoma.

S100A4 drives non-small cell lung cancer invasion, associates with poor prognosis, and is effectively targeted by the FDA-approved anti-helminthic agent niclosamide

S100A4 (metastasin-1), a metastasis-associated protein and marker of the epithelial to mesenchymal transition, contributes to several hallmarks of cancer and has been implicated in the progression of several types of cancer. However, the impacts of S100A4 signaling in lung cancer progression and its potential use as a target for therapy in lung cancer have not been properly explored. Using established lung cancer cell lines, we demonstrate that S100A4 knockdown reduces cell proliferation, invasion and three-dimensional invasive growth, while overexpression of S100A4 increases invasive potential. In patient-derived tissues, S100A4 is preferentially elevated in lung adenocarcinoma. This elevation is associated with lymphovascular invasion and decreased overall survival. In addition, depletion of S100A4 by shRNA inhibits NF-κB activity and decreases TNFα-induced MMP9 expression. Furthermore, inhibition of the NF-κB/MMP9 axis decreases lung carcinoma invasive potential. Niclosamide, a reported inhibitor of S100A4, blocks expression and function of S100A4 with a reduction in proliferation, invasion and NF-κB-mediated MMP9 expression. Collectively, this study highlights the importance of the S100A4/NF-κB/MMP9 axis in lung cancer invasion and provides a rationale for targeting S100A4 to combat lung cancer.

Ousting RAGE in melanoma: A viable therapeutic target?

Melanoma remains an important health concern, given the steady increase in incidence and acquisition of resistance to systemic therapies. The receptor for advanced glycation end products (RAGE) initially identified for its binding to advanced glycation end products was subsequently acknowledged as a pattern recognition receptor given its ability to recognize similar structural elements within numerous ligands. Recent studies have elucidated a plausible role of RAGE in melanoma progression through modulation of inflammatory, proliferative and invasive cellular responses. Several of its ligands including the S100 proteins and HMGB1 are being investigated for their involvement in melanoma metastasis and as potential biomarkers of the disease. Targeting RAGE signaling represents a viable therapeutic strategy which remains underexplored in cutaneous malignancies. Here we have summarized current knowledge on the functionality of RAGE with special focus on specific ligands enumerated in various in vitro and in vivo melanoma models.

Expression and Functional Analysis of Tumor-Related Factor S100A4 in Antler Stem Cells

Annual antler renewal is a stem cell-based epimorphic process driven by antler stem cells (ASCs) resident in antlerogenic periosteum (AP). Antlerogenic periosteal cells express a high level of S100A4, a metastasis-associated protein, which intrigued us to explore what role S100A4 could play in antler regeneration. The present study set out to investigate expression and effects of S100A4 in the ASCs and their progeny. The results showed that not only did cells from the AP express a high level of S100A4, but also the pedicle periosteum and the antler growth center. In the antler growth center, we found S100A4-positive cells were specifically located in blood vessel walls and in vascularized areas. In vitro, recombinant deer S100A4 protein stimulated the proliferation of the AP cells, promoted proliferation, migration and tube formation of human vascular endothelial cells, and enhanced migration of Hela cells, but not AP cells. These findings demonstrated that S100A4 in the ASCs may play a significant role in stimulating angiogenesis, proliferation, but not motility, of ASCs. Deer antlers offer a unique model to explore how rapid cell proliferation with a high level of S100A4 expression is elegantly regulated without becoming cancerous.

S100A4 in cancer progression and metastasis: A systematic review

Metastasis is the leading cause of cancer-related death and directly associates with cancer progression, resistance to anticancer therapy, and poor patient survival. Current efforts focusing on the underlying molecular mechanisms of cancer metastasis attract a special attention to cancer researchers. The epithelial-mesenchymal transition is a complex of molecular program during embryogenesis, inflammation, tissue fibrosis, and cancer progression and metastasis. S100A4, an important member of S100 family proteins, functions to increase the tumor progression and metastasis. The molecular mechanisms of S100A4 involving in the progression and metastasis are diverse in various malignant tumors. Detection of S100A4 expression becomes a promising candidate biomarker in cancer early diagnosis and prediction of cancer metastasis and therefore, S100A4 may be a therapeutic target. This review summarized up to date advancement on the role of S100A4 in human cancer development, progression, and metastasis and the underlying molecular events and then strategies to target S100A4 expression experimentally.

S100A7: from mechanism to cancer therapy

Within the tumor, malignant and stromal cells support each other by secreting a wide variety of growth factors and cytokines, allowing tumor growth and disease progression. The identification and regulation of those key factors in this crosstalk has opened the opportunity to develop new therapeutic strategies that not only act on the tumor cells but also on the stroma. Among these factors, S100A7 protein has gained interest in the last years. With key roles in cell motility its expression correlates with increased tumor growth, angiogenesis and metastatic potential. This work aims to deepen in the role played by extracellular S100A7 in the tumor microenvironment, offering a new integrative insight of its mechanism of action on each cellular compartment (tumor, endothelial, immune and fibroblast). As a result, we demonstrate its implication in cell migration and invasion, and its important contribution to the formation of a proinflammatory and proangiogenic environment that favors tumor progression and metastasis. Furthermore, we define its possible role in the pre-metastatic niche formation. Considering the relevance of S100A7 in cancer progression, we have developed neutralizing monoclonal antibodies, reporting for the first time the proof of principle of this promising therapeutic strategy for cancer treatment.

Molecular factors regulating E-cadherin expression in urothelial bladder cancer and their correlations with the clinicopathological features

This study aimed to assess the expression of S100A4, Twist and E-cadherin (mRNA and protein) in urothelial bladder cancer, investigate the correlation between them and evaluate their association with the clinicopathological features of the disease. The study included 54 patients diagnosed as urothelial bladder cancer of different stages and grades. The expression levels of S100A4, Twist and E-cadherin (mRNA and protein) in tissue samples were determined by quantitative RT-PCR and immunohistochemistry. The expression of S100A4 and Twist was significantly upregulated while E- cadherin was significantly downregulated in urothelial bladder cancer tissues compared to the adjacent surrounding normal bladder tissues at both mRNA and protein levels (p < 0.001). Expression levels of S100A4 and Twist were significantly higher in recurrent tumor than in non-recurrent tumors (p < 0.001) while the expression level of E-cadherin was significantly lower in recurrent tumors than in non-recurrent tumors at both mRNA and protein levels (p < 0.001). There was a significant positive correlation between S100A4 and Twist expressions (r = 0.875, p < 0.001) while significant negative correlations were found between E- cadherin and S100A4 expressions(r=- 0.803, p < 0.001) and between E-cadherin and Twist (r = -0.809, p < 0.001). Up-regulation of S100A4 and Twist and down-regulation of E-cadherin in urothelial bladder cancer tissues compared to adjacent normal tissues were observed. There was a significant negative correlation between S100A4 and E- cadherin and between E- cadherin and Twist expression. However, there was a significant positive correlation between S100A4 and Twist expressions. Furthermore, the alterations in the gene expression were associated with disease stage and grade.