The heterogeneity of tumor-associated macrophages and strategies to target it

Tumor-associated macrophages(TAMs)are emerging as targets for tumor therapy because of their primary role in promoting tumor progression.Several studies have been conducted to target TAMs by reducing their infiltration,depleting their numbers,and reversing their phenotypes to suppress tumor progression,leading to the development of drugs in preclinical and clinical trials.However,the heterogeneous characteristics of TAMs,including their ontogenetic and functional heterogeneity,limit their targeting.Therefore,in-depth exploration of the heterogeneity of TAMs,combined with immune checkpoint therapy or other therapeutic modalities could improve the efficiency of tumor treatment.This review focuses on the heterogeneous ontogeny and function of TAMs,as well as the current development of tumor therapies targeting TAMs and combination strategies.

Correlation of tumor-associated macrophage density and proportion of M2 subtypes with the pathological stage of colorectal cancer

BACKGROUND Colorectal cancer(CRC)is a prevalent global malignancy with complex prognostic factors.Tumor-associated macrophages(TAMs)have shown paradoxical associations with CRC survival,particularly concerning the M2 subset.AIM We aimed to establish a simplified protocol for quantifying M2-like TAMs and explore their correlation with clinicopathological factors.METHODS A cross-sectional study included histopathological assessment of paraffinembedded tissue blocks obtained from 43 CRC patients.Using CD68 and CD163 immunohistochemistry,we quantified TAMs in tumor stroma and front,focusing on M2 proportion.Demographic,histopathological,and clinical parameters were collected.RESULTS TAM density was significantly higher at the tumor front,with the M2 proportion three times greater in both zones.The tumor front had a higher M2 proportion,which correlated significantly with advanced tumor stage(P=0.04),pathological nodal involvement(P=0.04),and lymphovascular invasion(LVI,P=0.01).However,no significant association was found between the M2 proportion in the tumor stroma and clinicopathological factors.CONCLUSION Our study introduces a simplified protocol for quantifying M2-like TAMs in CRC tissue samples.We demonstrated a significant correlation between an increased M2 proportion at the tumor front and advanced tumor stage,nodal involvement,and LVI.This suggests that M2-like TAMs might serve as potential indicators of disease progression in CRC,warranting further investigation and potential clinical application.

Role of tumor-associated macrophages in common digestive system malignant tumors

Many digestive system malignant tumors are characterized by high incidence and mortality rate.Increasing evidence has revealed that the tumor microenvironment(TME)is involved in cancer initiation and tumor progression.Tumor-associated macrophages(TAMs)are a predominant constituent of the TME,and participate in the regulation of various biological behaviors and influence the prognosis of digestive system cancer.TAMs can be mainly classified into the antitumor M1 phenotype and protumor M2 phenotype.The latter especially are crucial drivers of tumor invasion,growth,angiogenesis,metastasis,immunosuppression,and resistance to therapy.TAMs are of importance in the occurrence,development,diagnosis,prognosis,and treatment of common digestive system malignant tumors.In this review,we summarize the role of TAMs in common digestive system malignant tumors,including esophageal,gastric,colorectal,pancreatic and liver cancers.How TAMs promote the development of tumors,and how they act as potential therapeutic targets and their clinical applications are also described.

Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke

Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke.

Role of Cyclin D1b in Inducing Macrophages Toward a Tumor-associated Macrophage-like Phenotype in Murine Breast Cancer

Objective:Tumor-associated macrophages(TAMs)of the M2 phenotype are frequently associated with cancer progression.Invasive cancer cells undergoing epithelial-mesenchymal transition(EMT)have a selective advantage as TAM activators.Cyclin D1b is a highly oncogenic splice variant of cyclin D1.We previously reported that cyclin D1b enhances the invasiveness of breast cancer cells by inducing EMT.However,the role of cyclin D1b in inducing macrophage differentiation toward tumor-associated macrophage-like cells remains unknown.This study aimed to explore the relationship between breast cancer cells overexpressing cyclin Dlb and TAMs.Methods:Mouse breast cancer 4T1 cells were transfected with cyclin D1b variant and co-cultured with macrophage cells in a Transwell coculture system.The expression of characteristic cytokines in differentiated macrophages was detected using qRT-PCR,ELISA and zymography assay.Tumor-associated macrophage distribution in a transplanted tumor was detected by immunofluorescence staining.The proliferation and migration ability of breast cancer cells was detected using the cell counting kit-8(CCK-8)assay,wound healing assay,Transwell invasion assay,and lung metastasis assay.Expression levels of mRNAs were detected by qRT-PCR.Protein expression levels were detected by Western blotting.The integrated analyses of The Cancer Genome Atlas(TCGA)datasets and bioinformatics methods were adopted to discover gene expression,gene coexpression,and overall survival in patients with breast cancer.Results:After co-culture with breast cancer cells overexpressing cyclin D1b,RAW264.7 macrophages were differentiated into an M2 phenotype.Moreover,differentiated M2-like macrophages promoted the proliferation and migration of breast cancer cells in turn.Notably,these macrophages facilitated the migration of breast cancer cells in vivo.Further investigations indicated that differentiated M2-like macrophages induced EMT of breast cancer cells accompanied with upregulation of TGF-β1 and integrinβ3 expression.Conclusion:Breast cancer cells transfected with cyclin D1b can induce the differentiation of macrophages into a tumor-associated macrophage-like phenotype,which promotes tumor metastasis in vitro and in vivo.

The Combined Effect of Lumenato and Ceramide in the Protection of Collagen Damage Induced by Neutrophils in Normal Human Dermal Fibroblasts

Introduction: Collagen is the primary structural protein fibroblasts produce in the skin’s extracellular matrix. Infiltration of neutrophils into the epidermis and dermis by exposure to UV causes collagen damage and contributes to photoaging. Methods: To study the combined effect of Lumenato and ceramide in preventing collagen-1 damage induced by phagocytes, we used co-cultures of normal human dermal fibroblasts (fibroblasts) and activated human neutrophils. The present study aimed to determine the protective effect of the combination of Lumenato and ceramide on fibroblast collagen-1 damage induced by neutrophils. Results: Lumenato (in the range of 6.5 - 208 μg/ml) or ceramide (in the range of 0.1 - 50 μM) inhibited the production of superoxides and MPO by TNFα-stimulated neutrophils, as well as the production of NO by LPS-stimulated macrophages in a dose-dependent manner. The combinations of Lumenato and ceramide, in low concentrations, caused synergistic prevention of fibroblasts’ collagen-1 damage induced by TNFα-activated neutrophils, detected by fluorescence immunostaining and WB analysis. MPO activity in the supernatants of the co-cultures was also synergistically inhibited. Adding Lumenato or ceramide singly or in combinations in these low concentrations to the fibroblast cultures did not affect the expression of collagen-1. The combinations of Lumenato or ceramide in these concentrations also caused a synergistic inhibition of NO production by activated macrophages. Conclusions: The results suggest that combining low concentrations of Lumenato and ceramide results in synergistic protection against fibroblasts’ collagen-1 damage induced by neutrophils, thus indicating their possible potential for enhanced skin health.

CRABP2 regulates infiltration of cancer-associated fibroblasts and immune response in melanoma

Finding biomarkers for immunotherapy is an urgent issue in cancer treatment.Cellular retinoic acid-binding protein 2(CRABP2)is a controversial factor in the occurrence and development of human tumors.However,there is limited research on the relationship between CRABP2 and immunotherapy response.This study found that negative correlations of CRABP2 and immune checkpoint markers(PD-1,PD-L1,and CTLA-4)were observed in breast invasive carcinoma(BRCA),skin cutaneous melanoma(SKCM),stomach adenocarcinoma(STAD)and testicular germ cell tumors(TGCT).In particular,in SKCM patients who were treated with PD-1 inhibitors,high levels of CRABP2 predicted poor prognosis.Additionally,CRABP2 expression was elevated in cancer-associated fibroblasts(CAFs)at the single-cell level.The expression of CRABP2 was positively correlated with markers of CAFs,such as MFAP5,PDPN,ITGA11,PDGFRα/βand THY1 in SKCM.To validate the tumor-promoting effect of CRABP2 in vivo,SKCM xenograft mice models with CRABP2 overexpression have been constructed.These models showed an increase in tumor weight and volume.Enrichment analysis indicated that CRABP2 may be involved in immunerelated pathways of SKCM,such as extracellular matrix(ECM)receptor interaction and epithelial-mesenchymal transition(EMT).The study suggests that CRABP2 may regulate immunotherapy in SKCM patients by influencing infiltration of CAFs.In conclusion,this study provides new insights into the role of CRABP2 in immunotherapy response.The findings suggest that CRABP2 may be a promising biomarker for PD-1 inhibitors in SKCM patients.Further research is needed to confirm these findings and to explore the clinical implications of CRABP2 in immunotherapy.

Uniportal video-assisted thoracoscopic fissureless right upper lobe anterior segmentectomy for inflammatory myofibroblastic tumor:A case report

BACKGROUND Inflammatory myofibroblastic tumors(IMTs)are exceptionally rare neoplasms with intermediate malignant potential.Surgery is the accepted treatment option,aiming for complete resection with clear margins.CASE SUMMARY A 39-year-old woman presented with a growing solitary pulmonary nodule measuring 2.0 cm in the right upper lobe(RUL)of the lung.The patient underwent a RUL anterior segmentectomy using uniportal video-assisted thoracoscopy.A preliminary tissue diagnosis indicated malignancy;however,it was later revised to an IMTs.Due to the absence of a minor fissure between the right upper and middle lobes,an alternative resection approach was necessary.Therefore,we utilized indocyanine green injection to aid in delineating the intersegmental plane.Following an uneventful recovery,the patient was discharged on the third postoperative day.Thereafter,annual chest tomography scans were scheduled to monitor for potential local recurrence.CONCLUSION This case underscores the challenges in diagnosing and managing IMTs,showing the importance of accurate pathologic assessments and tailored surgical strategies.

Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression

Colorectal cancer(CRC)remains one of the most commonly diagnosed and deadliest types of cancer worldwide.CRC displays a desmoplastic reaction(DR)that has been inversely associated with poor prognosis;less DR is associated with a better prognosis.This reaction generates excessive connective tissue,in which cancer-associated fibroblasts(CAFs)are critical cells that form a part of the tumor microenvironment.CAFs are directly involved in tumorigenesis through different mechanisms.However,their role in immunosuppression in CRC is not well understood,and the precise role of signal transducers and activators of transcription(STATs)in mediating CAF activity in CRC remains unclear.Among the myriad chemical and biological factors that affect CAFs,different cytokines mediate their function by activating STAT signaling pathways.Thus,the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT inhibitors.Here,we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

Fibroblast growth factor 21 inhibits ferroptosis following spinal cord injury by regulating heme oxygenase-1

Interfering with the ferroptosis pathway is a new strategy for the treatment of spinal cord injury.Fibroblast growth factor 21 can inhibit ferro ptosis and promote neurofunctional recovery,while heme oxygenase-1 is a regulator of iron and reactive oxygen species homeostasis.The relationship between heme oxygenase-1and ferroptosis remains controve rsial.In this study,we used a spinal co rd injury rat model to show that the levels of fibroblast growth factor 21 in spinal co rd tissue decreased after spinal cord injury.In addition,there was a significant aggravation of ferroptosis and a rapid increase in heme oxygenase-1 expression after spinal cord injury.Furthe r,heme oxygenase-1 aggravated fe rroptosis after spinal cord injury,while fibroblast growth factor 21 inhibited fe rroptosis by downregulating heme oxygenase-1.Thus,the activation of fibroblast growth factor 21 may provide a potential treatment for spinal co rd injury.These findings could provide a new potential mechanistic explanation for fibroblast growth factor 21 in the treatment of spinal cord injury.

Roles of fibroblast growth factors in the treatment of diabetes

Diabetes affects about 422 million people worldwide,causing 1.5 million deaths each year.However,the incidence of diabetes is increasing,including several types of diabetes.Type 1 diabetes(5%-10%of diabetic cases)and type 2 diabetes(90%-95%of diabetic cases)are the main types of diabetes in the clinic.Accumulating evidence shows that the fibroblast growth factor(FGF)family plays important roles in many metabolic disorders,including type 1 and type 2 diabetes.FGF consists of 23 family members(FGF-1-23)in humans.Here,we review current findings of FGFs in the treatment of diabetes and management of diabetic complications.Some FGFs(e.g.,FGF-15,FGF-19,and FGF-21)have been broadly investigated in preclinical studies for the diagnosis and treatment of diabetes,and their therapeutic roles in diabetes are currently under investigation in clinical trials.Overall,the roles of FGFs in diabetes and diabetic complications are involved in numerous processes.First,FGF intervention can prevent high-fat diet-induced obesity and insulin resistance and reduce the levels of fasting blood glucose and triglycerides by regulating lipolysis in adipose tissues and hepatic glucose production.Second,modulation of FGF expression can inhibit renal and cardiac fibrosis by regulating the expression of extracellular matrix components,promote diabetic wound healing process and bone repair,and inhibit cancer cell proliferation and migration.Finally,FGFs can regulate the activation of glucoseexcited neurons and the expression of thermogenic genes.

Attenuation of the Activation of NLRP3 Inflammasome in Fibroblast Like Synoviocytes of Rheumatoid Arthritis by Baicalin through Regulating the Let-7i-3p/PI3K/Akt/NF-κB Signaling Axis

[Objectives]To study the effect and mechanism of baicalin on the activation of NLRP3 inflammasome in human fibroblast like synoviocytes of rheumatoid arthritis(HFLS-RA).[Methods]To confirm that baicalin alleviated the activation of NLRP3 inflammasome in HFLS-RA,the expression of NLRP3 before and after baicalin treatment was observed by immunofluorescence.Western blot was used to detect the protein expression of p-PI3K,p-Akt,NF-κB p65,NLRP3,ASC and caspase-1 after baicalin treatment for 48 h,and the contents of IL-1 and IL-18 in the supernatents were detected by ELISA.In order to explore the mechanism of baicalin alleviating the activation of NLRP3 inflammasome,the corresponding relationship between let-7i-3p and PIK3CA was verified by double luciferin and Westen blot analysis.The expression of let-7i-3p and PI3K before and after baicalin intervention was detected by RT-qPCR.let-7i-3p interference was used to verify whether baicalin mitigated the activation of enhanced NLRP3 inflammasome.[Results]Baicalin(50 and 100 mg/L)significantly reduced the activation of NLRP3 inflammasome,inhibited the protein expressions of p-PI3K,p-Akt,NF-κB p65,NLRP3,ASC and caspase-1,and the secretion of IL-1 and IL-18.let-7i-3p and PIK3CA had a targeted correspondence,and baicalin up-regulated the expression of let-7i-3p and down-regulated the expression of PIK3CA.Baicalin attenuated the activation of NLRP3 inflammasome enhanced by let-7i-3p interference.[Conclusions]Baicalin can up-regulate let-7i-3p expression,inhibit PI3K/Akt/NF-κB signal transduction,and thus reduce the activation of NLRP3 inflammasome in HFLS-RA.

RNA sequencing of exosomes secreted by fibroblast and Schwann cells elucidates mechanisms underlying peripheral nerve regeneration

Exosomes exhibit complex biological functions and mediate a variety of biological processes,such as promoting axonal regeneration and functional recove ry after injury.Long non-coding RNAs(IncRNAs)have been reported to play a crucial role in axonal regeneration.Howeve r,the role of the IncRNA-microRNAmessenger RNA(mRNA)-competitive endogenous RNA(ceRNA)network in exosome-mediated axonal regeneration remains unclear.In this study,we performed RNA transcriptome sequencing analysis to assess mRNA expression patterns in exosomes produced by cultured fibroblasts(FC-EXOs)and Schwann cells(SCEXOs).Diffe rential gene expression analysis,Gene Ontology analysis,Kyoto Encyclopedia of Genes and Genomes analysis,and protein-protein intera ction network analysis were used to explo re the functions and related pathways of RNAs isolated from FC-EXOs and SC-EXOs.We found that the ribosome-related central gene Rps5 was enriched in FC-EXOs and SC-EXOs,which suggests that it may promote axonal regeneration.In addition,using the miRWalk and Starbase prediction databases,we constructed a regulatory network of ceRNAs targeting Rps5,including 27 microRNAs and five IncRNAs.The ceRNA regulatory network,which included Ftx and Miat,revealed that exsosome-derived Rps5 inhibits scar formation and promotes axonal regeneration and functional recovery after nerve injury.Our findings suggest that exosomes derived from fibro blast and Schwann cells could be used to treat injuries of peripheral nervous system.

Tumor-associated macrophages regulate gastric cancer cell invasion and metastasis through TGFβ2/NF-κB/Kindlin-2 axis

Objective: Recent studies have shown that tumor-associated macrophages(TAMs) play an important role in cancer invasion and metastasis. Our previous studies have reported that TAMs promote the invasion and metastasis of gastric cancer(GC) cells through the Kindlin-2 pathway. However, the mechanism needs to be clarified.Methods: THP-1 monocytes were induced by PMA/interleukin(IL)-4/IL-13 to establish an efficient TAM model in vitro and M2 macrophages were isolated via flow cytometry. A dual luciferase reporter system and chromatin immunoprecipitation(Ch IP) assay were used to investigate the mechanism of transforming growth factor β2(TGFβ2) regulating Kindlin-2 expression. Immunohistochemistry was used to study the relationships among TAM infiltration in human GC tissues, Kindlin-2 protein expression, clinicopathological parameters and prognosis in human GC tissues. A nude mouse oncogenesis model was used to verify the invasion and metastasis mechanisms in vivo.Results: We found that Kindlin-2 expression was upregulated at both m RNA and protein levels in GC cells cocultured with TAMs, associated with higher invasion rate. Kindlin-2 knockdown reduced the invasion rate of GC cells under coculture condition. TGFβ2 secreted by TAMs regulated the expression of Kindlin-2 through the transcription factor NF-кB. TAMs thus participated in the progression of GC through the TGFβ2/NF-κB/Kindlin-2 axis. Kindlin-2 expression and TAM infiltration were significantly positively correlated with TNM stage, and patients with high Kindlin-2 expression had significantly poorer overall survival than patients with low Kindlin-2 expression. Furthermore, Kindlin-2 promoted the invasion of GC cells in vivo.Conclusions: This study elucidates the mechanism of TAMs participating in GC cell invasion and metastasis through the TGFβ2/NF-κB/Kindlin-2 axis, providing a possibility for new treatment options and approaches.

Colorectal cancer vaccines: Tumor-associated antigens vs neoantigens

Therapeutic options for the treatment of colorectal cancer(CRC) are diverse but still not always satisfying. Recent success of immune checkpoint inhibition treatment for the subgroup of CRC patients suffering from hypermutated tumors suggests a permanent role of immune therapy in the clinical management of CRC. Substantial improvement in treatment outcome could be achieved by development of efficient patient-individual CRC vaccination strategies. This mini-review summarizes the current knowledge on the two general classes of targets: tumor-associated antigens(TAAs) and tumorspecific antigens. TAAs like carcinoembryonic antigen and melanoma associated antigen are present in and shared by a subgroup of patients and a variety of clinical studies examined the efficacy of different TAA-derived peptide vaccines. Combinations of several TAAs as the next step and the development of personalized TAA-based peptide vaccines are discussed. Improvements of peptidebased vaccines achievable by adjuvants and immunestimulatory chemotherapeutics are highlighted. Finally, we sum up clinical studies using tumor-specific antigens-in CRC almost exclusively neoantigens-which revealed promising results; particularly no severe adverse events were reported so far. Critical progress for clinical outcomes can be expected by individualizing neoantigen-based peptide vaccines and combining them with immunestimulatory chemotherapeutics and immune checkpoint inhibitors. In light of these data and latest developments, truly personalized neoantigen-based peptide vaccines can be expected to fulfill modern precision medicine's requirements and will manifest as treatment pillar for routine clinical management of CRC.

Targeting and exploitation of tumor-associated neutrophils to enhance immunotherapy and drug delivery for cancer treatment

Neutrophils,the most abundant leukocytes in human blood,are essential fighter immune cells against microbial infection.Based on the finding that neutrophils can either restrict or promote cancer progression,tumor-associated neutrophils(TAN)are classified into anti-tumor N1 and pro-tumor N2 subsets.One of the major mechanisms underlying the tumor-promoting function of N2-TANs is suppression of adaptive immune cells,in particular,cytotoxic T lymphocytes.Currently,no established methodologies are available that can unequivocally distinguish immunosuppressive TANs and granulocytic/polymorphonuclear myeloid-derived suppressor cells(G/PMN-MDSC).In view of the critical role of PMN-MDSCs in immune evasion and resistance to cancer immunotherapy,as established from data obtained with diverse cancer models,therapeutic strategies targeting these cells have been actively developed to enhance the efficacy of immunotherapy.Here,we have reviewed the available literature on strategies targeting PMN-MDSCs and summarized the findings into four categories:(1)depletion of existing PMN-MDSCs,(2)blockade of the development of PMNMDSCs,(3)blockade of PMN-MDSC recruitment,(4)inhibition of immunosuppressive function.Owing to their high mobility to inflamed organs and ability to trespass the blood-brain barrier,neutrophils are outstanding candidate carriers in nanoparticle-based therapies.Another attractive application of neutrophils in cancer therapy is the use of neutrophil membrane-derived nanovesicles as a surrogate of extracellular vesicles for more efficient and scalable drug delivery.In the second part of the review,we have highlighted recent advances in the field of neutrophil-based cancer drug delivery.Overall,we believe that neutrophil-based therapeutics are a rapidly growing area of cancer therapy with significant potential benefits.

Promotion of Sema4D expression by tumor-associated macrophages: Significance in gastric carcinoma

AIM To study the role of semaphorin 4 D(Sema4 D) expression promoted by tumor-associated macrophages(TAMs) in gastric carcinoma cells and its clinical significance in the invasion and metastasis of gastric carcinoma.METHODS CD68 and Sema4 D expression was analyzed in gastric carcinoma and adjacent normal tissues from 290 patients using the immunohistochemical streptavidinperoxidase method, and their relationships with clinicopathological features were evaluated. Human M2 macrophages were induced in vitro and co-cultured in non-contact with gastric carcinoma SGC-7901 cells. Changes in the secretory Sema4 D level in the SGC-7901 cell supernatant were measured using an enzymelinked immunosorbent assay. The effects of TAMs on SGC-7901 cell invasion and migration were assessed with invasion and migration assays, respectively.RESULTS CD68 and Sema4 D protein expression was significantly higher in gastric carcinoma tissues than in adjacent normal tissues(71.7% vs 33.8% and 74.5% vs 42.8%, respectively; P < 0.01). CD68 and Sema4 D protein expression was significantly associated with histological differentiation, TNM stage, and lymph node metastasis(P < 0.05), and their expression levels were positively correlated with one another(r = 0.467, P < 0.01). In the in vitro experiment, secretory Sema4 D protein expression was significantly increased in the supernatant of SGC-7901 cells co-cultured with TAMs compared with the blank control(1224.13 ± 29.43 vs 637.15 ± 33.84, P < 0.01). Cell invasion and metastasis were enhanced in the Transwell invasion and migration assays(P < 0.01).CONCLUSION TAMs promote the invasion and metastasis of gastric carcinoma cells possibly through upregulated secretory Sema4 D protein expression. Combined detection of TAM markers, CD68 and Sema4 D, in gastric carcinoma tissue shows potential to predict the trend of gastric carcinoma progression.

Update on a tumor-associated NADH oxidase in gastric cancer cell growth

Gastric cancer is one of the most common human malignancies, and its prevalence has been shown to be well-correlated with cancer-related deaths worldwide. Regrettably, the poor prognosis of this disease is mainly due to its late diagnosis at advanced stages after the cancer has already metastasized. Recent research has emphasized the identification of cancer biomarkers in the hope of diagnosing cancer early and designing targeted therapies to reverse cancer progression. One member of a family of growth-related nicotinamide adenine dinucleotide(NADH or hydroquinone) oxidases is tumor-associated NADH oxidase(t NOX; ENOX2). Unlike its counterpart CNOX(ENOX1), identified in normal rat liver plasma membranes and shown to be stimulated by growth factors and hormones, t NOX activity purified from rat hepatoma cells is constitutively active. Its activity is detectable in the sera of cancer patients but not in those of healthy volunteers, suggesting its clinical relevance. Interestingly, t NOX expression was shown to be present in an array of cancer cell lines. More importantly, inhibition of t NOX was well correlated with reduced cancer cell growth and induction of apoptosis. RNA interference targeting t NOX expression in cancer cells effectively restored non-cancerous phenotypes, further supporting the vital role of t NOX in cancer cells. Here, we review the regulatory role of t NOX in gastric cancer cell growth.

Activation of Toll-like receptors signaling in non-small cell lung cancer cell line induced by tumor-associated macrophages

Background： Inflammation is often linked with the progress and poor outcome of lung cancer. The understanding of the relationship between tumor-associated macrophages （TAMs） and lung cancer cells involves in the underlying mechanism of inflammatory cytokine production. Toll-like receptors （TLRs） are engaged in promoting the production of pro-inflammatory cytokines and play an important role in tumor immunology. Methods： To investigate the mechanisms by which TAMs influence the production of pro-inflammatory cytoldnes in lung cancer cells, we established an in vitro coculture system using TAMs and human non- small cell lung cancer （NSCLC） cell line SPC-A1. Levels of interleukin （IL）-113, IL-6 and IL-8 in SPC-A1 were evaluated by RT-PCR and cytometric bead array assay after being cocultured with TAMs. Expression changes of TLRs and TLRs signaling pathway proteins in SPC-Al were further confirmed by RT-PCR and western blot. The level changes of IL-1β, IL-6 and IL-8 in SPC-Al were also detected after the stimulation of TLRs agonists. Results： We found that the phenotype markers of TAMs were highly expressed after stimulating human monocyte cell line THP-1 by phorbol-12-myristate-β-acetate （PMA）. Higher mRNA and supernate secretion levels of IL-1β, IL-6 and IL-8 were detected in SPC-A1 after being eocultured with TAMs. We also found that TLR1, TLR6 and TLR7 were up-regulated in SPC-A1 in the coculture system with TAMs. Meanwhile, TLRs signaling pathway proteins were also significantly activated. Moreover, pre-treatment with agonist ligands for TLR1, TLR6 and TLR7 could dramatically promote inductions of IL-1β, IL-6 and IL-8. Conclusions： These findings demonstrated that TAMs may enhance IL-1β, IL-6 and IL-8 expressions via TLRs signaling pathway. We conclude that TAMs contribute to maintain the inflammation microenvironment and ultimately promote the development and progression of lung cancer.

Analysis of invasiveness and tumor-associated macrophages infiltration in solid pseudopapillary tumors of pancreas

BACKGROUND Solid pseudopapillary tumor(SPT)is a rare pancreatic tumor.Considering its malignant behaviors,SPT has been classified as a low-grade malignant tumor.Indeed,only 9.2%of all SPT patients are initially diagnosed as malignant with invasion or metastasis.Thus,one of the challenges in managing SPT patients is predicting malignant behavior.AIM To investigate the malignant behavior and tumor-associated macrophage(TAM)infiltration between different histopathologic features of SPT patients.METHODS Twenty-five formalin-fixed paraffin-embedded tissue samples from 22 patients pathologically diagnosed with an SPT between 2009 and 2019 at West China Hospital were included in this retrospective study.Integrity of the capsule and growth pattern of the tumor cells was assessed microscopically in hematoxylineosin(HE)-stained sections.Based on the histopathological features,the SPT patients were divided into two groups:capsule or invasion.Clinical features,malignant behavior,and TAM infiltration were compared between the two groups.RESULTS Among the 22 SPT patients,11 were identified for each group,having either a capsule or invasion histopathologic feature.Malignant behavior was more frequent in the invasion group,including 2 patients who had peripheral organ invasion,3 with liver metastasis,and 1 with both lymph node and spleen metastases(P=0.045).Ki-67 index of more than 3%was also more frequent in the invasion group(P=0.045).Immunohistochemical analysis showed that the invasion group had a significant increase of CD68-positive TAMs in intratumor and peritumor sites in comparison with the capsule group(all P<0.0001).Similarly,CD163-positive M2-like macrophages were also markedly increased in the intratumor and peritumor sites in the invasion group(all P<0.0001).At the liver metastasis site,both intratumor and peritumor tissues showed relatively high-level CD68-positive TAMs and CD163-positive M2-like macrophages infiltration.However,the differences between the intratumor,peritumor and normal hepatic tissues did not reach statistical significance(all P>0.05).CONCLUSION SPT patients with invasion evident under microscope were more likely to exhibit malignant behavior and TAM infiltration,especially M2-like macrophages.This finding can help in future investigations of the underlying mechanism of TAM-mediated SPT malignant behavior.