Molecular mechanism of pancreatic ductal adenocarcinoma:The heterogeneity of cancer-associated fibroblasts and key signaling pathways

Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a detailed exploration of epidemiological trends in pancreatic cancer and key molecular drivers,such as mutations in CDKN2A,KRAS,SMAD4,and TP53,along with the influence of cancer-associated fibroblasts(CAFs)on disease progression.In particular,we focused on the pivotal roles of signaling pathways such as the transforming growth factor-βand Wnt/β-catenin pathways in the development of pancreatic cancer and investigated their application in emerging therapeutic strategies.This study provides new scientific perspectives on pancreatic cancer treatment,especially in the development of precision medicine and targeted therapeutic strategies,and demonstrates the importance of signaling pathway research in the development of effective therapeutic regimens.Future studies should explore the subtypes of CAFs and their specific roles in the tumor microenvironment to devise more effective therapeutic methods.

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.

Lysine demethylase 5B transcriptionally regulates TREM1 in human cardiac fibroblasts

Background:A differential gene,triggering receptor expressed on myeloid cells 1(TREM1),was identified in blood sequencing datasets from myocardial infarction patients and healthy controls.Myocardialfibrosis following myocardial infarction significantly contributes to cardiac dysfunction.Objectives:This study aimed to unveil the intrinsic regulatory mechanism of TREM1 in myocardialfibrosis.Methods:Mimicking pathology by angiotensin II(Ang II)treatment of human cardiacfibroblasts(HCFs),the impacts of TREM1 knockdown on its proliferation,migration,and secretion of the pro-fibrotic matrix were identified.Using the Human Transcription Factor Database(HumanTFDB)website,lysine-specific demethylase 5B(KDM5B)was found to bind to the TREM1 promoter,which was further validated through luciferase reporter and chromatin immunoprecipitation(ChIP).By promoting KDM5B overexpression,its effect on the regulation of TREM1 was examined.Results:TREM1 knockdown suppressed the proliferation,migration,and secretion of the pro-fibrotic matrix in HCFs upon Ang II treatment.KDM5B bound to the TREM1 promoter and upregulated its transcriptional expression.Furthermore,KDM5B overexpression reversed the regulation of the above cellular phenotypes by TREM1 knockdown.Conclusion:This study sheds light on the positive regulation of TREM1 by KDM5B,demonstrating their role in promoting myocardialfibrosis.Thisfinding provides a theoretical foundation for understanding disease pathology and potentially advancing the development of new targeted therapies.

Resveratrol inhibits pancreatic cancer proliferation and metastasis by depleting senescent tumor-associated fibroblasts

BACKGROUND Pancreatic cancer,a formidable gastrointestinal neoplasm,is characterized by its insidious onset,rapid progression,and resistance to treatment,which often lead to a grim prognosis.While the complex pathogenesis of pancreatic cancer is well recognized,recent attention has focused on the oncogenic roles of senescent tumor-associated fibroblasts.However,their precise role in pancreatic cancer remains unknown.Resveratrol is a natural polyphenol known for its multifaceted biological actions,including antioxidative and neuroprotective properties,as well as its potential to inhibit tumor proliferation and migration.Our current investigation builds on prior research and reveals the remarkable ability of resveratrol to inhibit pancreatic cancer proliferation and metastasis.AIM To explore the potential of resveratrol in inhibiting pancreatic cancer by targeting senescent tumor-associated fibroblasts.METHODS Immunofluorescence staining of pancreatic cancer tissues revealed prominent coexpression ofα-SMA and p16.HP-1 expression was determined using immunohistochemistry.Cells were treated with the senescence-inducing factors known as 3CKs.Long-term growth assays confirmed that 3CKs significantly decreased the CAF growth rate.Western blotting was conducted to assess the expression levels of p16 and p21.Immunofluorescence was performed to assess LaminB1 expression.Quantitative real-time polymerase chain reaction was used to measure the levels of several senescence-associated secretory phenotype factors,including IL-4,IL-6,IL-8,IL-13,MMP-2,MMP-9,CXCL1,and CXCL12.A scratch assay was used to assess the migratory capacity of the cells,whereas Transwell assays were used to evaluate their invasive potential.RESULTS Specifically,we identified the presence of senescent tumor-associated fibroblasts within pancreatic cancer tissues,linking their abundance to cancer progression.Intriguingly,Resveratrol effectively eradicated these fibroblasts and hindered their senescence,which consequently impeded pancreatic cancer progression.CONCLUSION This groundbreaking discovery reinforces Resveratrol's stature as a potential antitumor agent and positions senescent tumor-associated fibroblasts as pivotal contenders in future therapeutic strategies against pancreatic cancer.

Unraveling the role of cancer-associated fibroblasts in colorectal cancer

Within the intricate milieu of colorectal cancer(CRC)tissues,cancer-associated fibroblasts(CAFs)act as pivotal orchestrators,wielding considerable influence over tumor progression.This review endeavors to dissect the multifaceted functions of CAFs within the realm of CRC,thereby highlighting their indispensability in fostering CRC malignant microenvironment and indicating the development of CAFs-targeted therapeutic interventions.Through a comprehensive synthesis of current knowledge,this review delineates insights into CAFsmediated modulation of cancer cell proliferation,invasiveness,immune evasion,and neovascularization,elucidating the intricate web of interactions that sustain the pro-tumor metabolism and secretion of multiple factors.Additionally,recognizing the high level of heterogeneity within CAFs is crucial,as they encompass a range of subtypes,including myofibroblastic CAFs,inflammatory CAFs,antigen-presenting CAFs,and vessel-associated CAFs.Innovatively,the symbiotic relationship between CAFs and the intestinal microbiota is explored,shedding light on a novel dimension of CRC pathogenesis.Despite remarkable progress,the orchestrated dynamic functions of CAFs remain incompletely deciphered,underscoring the need for continued research endeavors for therapeutic advancements in CRC management.

Exosomes from umbilical cord mesenchymal stromal cells promote the collagen production of fibroblasts from pelvic organ prolapse

BACKGROUND Pelvic organ prolapse(POP)involves pelvic organ herniation into the vagina due to pelvic floor tissue laxity,and vaginal structure is an essential factor.In POP,the vaginal walls exhibit abnormal collagen distribution and decreased fibroblast levels and functions.The intricate etiology of POP and the prohibition of trans-vaginal meshes in pelvic reconstruction surgery present challenges in targeted therapy development.Human umbilical cord mesenchymal stromal cells(hucMSCs)present limitations,but their exosomes(hucMSC-Exo)are promising therapeutic tools for promoting fibroblast proliferation and extracellular matrix remodeling.suppressed inflammation in POP group fibroblasts,stimulated primary fibroblast growth,and elevated collagen I(Col1)production in vitro.High-throughput RNA-seq of fibroblasts treated with hucMSC-Exo and miRNA sequencing of hucMSC-Exo revealed that abundant exosomal miRNAs downregulated matrix metalloproteinase 11(MMP11)expression.CONCLUSION HucMSC-Exo normalized the growth and function of primary fibroblasts from patients with POP by promoting cell growth and Col1 expression in vitro.Abundant miRNAs in hucMSC-Exo targeted and downregulated MMP11 expression.HucMSC-Exo-based therapy may be ideal for safely and effectively treating POP.

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.

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.

Effects of Serum Concentration, Synchronization Time and Confluence on the Cell-Cycle Synchronization Efficiency of Goat Fibroblasts

This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference in the percentage of nucleated fibroblasts in the G0/G1 stage between serum concentrations of 0.3% and 0.4% (83.89% and 82.69%, respectively, P > 0.05) as well as between serum concentrations of 0.2% and 0.5% (76.95% and 75.46%, respectively, P > 0.05). The percentage of nucleated fibroblasts in the G0/G1 stage was highest at the concentration of 0.3% and lowest in the control group (83.89% vs. 62.67%, P 0.05). The beneficial effect of high confluence was confirmed by the large percentage of nucleated fibroblasts at the G0/G1 stage. The 60% confluency was significantly lower than the 80% and 100% confluency (73.44%, 86.63%, and 87.17%, respectively, P < 0.05). The results indicate that the goat fibroblast cycle synchronization is the most effective at the serum concentration of 0.3%, 72 hours of synchronization and 100% confluency.

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

Culture in vitro and Cryopreservation of Shouguang Black Chicken Fibroblasts

[Objective] The aim of this study was to establish the in vitro culture system of chicken fibroblasts.[Method] Tissue explant method and enzymatic digestion method were used to separate and culture chicken skin fibroblasts respectively.The rate of cell growth,cryopreservation and recovery were compared.[Result] The primary chicken fibroblasts prepared by enzymatic digestion grew faster and converged together to form monolayer on 5 d post preparation;the passage cells prepared by these 2 methods grew at similar speed and formed monolayer within 2-3 d;homogeneous fibroblasts could be obtained by trypsin digestion and repeated attachment for 3-4 passages;there were 75%-80% of cells survived after cryopreservation and recovery;the growth curves of embryonic fibroblasts and skin fibroblasts were all normal and the two kind of cells still retained the normal number of chromosomes even at the twelfth passage.[Conclusion] The feeder layer cells needed for establishing ES cell lines could be obtained by culturing chicken fibroblasts through both tissue explant method and enzymatic digestion method.This study provided a basis for the successful establishment of ES cell lines.

Astragaloside Ⅳ inhibits pathological functions of gastric cancer-associated fibroblasts

AIM To investigate the inhibitory effect of astragaloside IV on the pathological functions of cancer-associated fibroblasts,and to explore the underlying mechanism.METHODS Paired gastric normal fibroblast(GNF) and gastric cancer-associated fibroblast(GCAF) cultures were established from resected tissues. GCAFs were treated with vehicle control or different concentrations of astragaloside Ⅳ. Conditioned media were prepared from GNFs,GCAFs,control-treated GCAFs,and astragaloside Ⅳ-treated GCAFs,and used to culture BGC-823 human gastric cancer cells. Proliferation,migration and invasion capacities of BGC-823 cells were determined by MTT,wound healing,and Transwell invasion assays,respectively. The action mechanism of astragaloside Ⅳ was investigated by detecting the expression of micro RNAs and the expression and secretion of the oncogenic factor,macrophage colonystimulating factor(M-CSF),and the tumor suppressive factor,tissue inhibitor of metalloproteinase 2(TIMP2),in different groups of GCAFs. The expression of the oncogenic pluripotency factors SOX2 and NANOG in BGC-823 cells cultured with different conditioned media was also examined.RESULTS GCAFs displayed higher capacities to induce BGC-823 cell proliferation,migration,and invasion than GNFs(P < 0.01). Astragaloside Ⅳ treatment strongly inhibited the proliferation-,migration-and invasion-promoting capacities of GCAFs(P < 0.05 for 10 μmol/L,P < 0.01 for 20 μmol/L and 40 μmol/L). Compared with GNFs,GCAFs expressed a lower level of micro RNA-214(P < 0.01) and a higher level of micro RNA-301 a(P < 0.01). Astragaloside Ⅳ treatment significantly upregulated micro RNA-214 expression(P < 0.01) and down-regulated micro RNA-301 a expression(P < 0.01) in GCAFs. Reestablishing the micro RNA expression balance subsequently suppressed M-CSF production(P < 0.01) and secretion(P < 0.05),and elevated TIMP2 production(P < 0.01) and secretion(P < 0.05). Consequently,the ability of GCAFs to increase SOX2 and NANOG expression in BGC-823 cells was abolished by astragaloside Ⅳ.CONCLUSION Astragaloside Ⅳ can inhibit the pathological functions of GCAFs by correcting their dysregulation of micro RNA expression,and it is promisingly a potent therapeutic agent regulating tumor microenvironment.

Role of cancer-associated fibroblasts in invasion and metastasis of gastric cancer

Cancer-associated fibroblasts(CAFs) are important components of various types of tumors,including gastric cancer(GC).During tumorigenesis and progression,CAFs play critical roles in tumor invasion and metastasis via a series of functions including extracellular matrix deposition,angiogenesis,metabolism reprogramming and chemoresistance.However,the mechanism of the interaction between gastric cancer cells and CAFs remains largely unknown.Micro RNAs(mi RNAs) are a class of non-coding small RNA molecules,and their expression in CAFs not only regulates the expression of a number of target genes but also plays an essential role in the communication between tumor cells and CAFs.In this review,we provide an overview of recent studies on CAF mi RNAs in GC and the relevant signaling pathways in gastrointestinal tumors.Focusing the attention on these signaling pathways may help us better understand their role in tumor invasion and metastasis and identify new molecular targets for therapeutic strategies.

Cancer-associated fibroblasts in hepatocellular carcinoma

The hepatic stellate cells in the liver are stimulated sustainably by chronic injury of the hepatocytes, activating myofibroblasts, which produce abundant collagen. Myofibroblasts are the major source of extracellular proteins during fibrogenesis, and may directly, or secreted products, contribute to carcinogenesis and tumor progression. Cancer-associated fibroblasts(CAFs) are one of the components of the tumor microenvironment that promote the proliferation and invasion of cancer cells by secreting various growth factors and cytokines. CAFs crosstalk with cancer cells stimulates tumor progression by creating a favorable microenvironment for progression, invasion, and metastasis through the epithelial-mesenchymal transition. Basic studies on CAFs have advanced, and the role of CAFs in tumors has been elucidated. In particular, for hepatocellular carcinoma, carcinogenesis from cirrhosis is a known fact, and participation of CAFs in carcinogenesis is supported. In this review, we discuss the current literature on the role of CAFs and CAF-related signaling in carcinogenesis, crosstalk with cancer cells, immunosuppressive effects, angiogenesis, therapeutic targets, and resistance to chemotherapy. The role of CAFs is important in cancer initiation and progression. CAF-targeted therapy may be effective for suppression not only of fibrosis but also cancer progression.

Effects of Fuzhenghuayu decoction on collagen synthesis of cultured hepatic stellate cells,hepatocytes and fibroblasts in rats

AIM To study the mechanism of Fuzhenghuayu (FZHY) decoction on anti liver fibrosis. METHODS FZHY 10% decoction sera was incubated with rat normal subcultured hepatic stellate cells (HSC) and fibrotic primarily cultured HSC, normal and fibrotic hepatocytes and subcultured skin fibroblasts separately. Cell intracellular and extracellular collagen synthesis rates were measured by the method of Proline impulse and collagenase digestion. RESULTS For primarily cultured HSC and hepatocytes, both of intracellular and extracellular collagen synthesis rates decreased in the drug sera group. For the normal subcultured HSC and primarily cultured hepatocytes, the extracellular collagen secretion was decreased obviously by the drug sera, and intracellular collagen synthesis rates were inhibited to some extents. For fibroblasts, both intracellular and extracellular collagen synthesis rates were inhibited some what, but no significant differences were found. CONCLUSION The mechanism of FZHY decoction on anti liver fibrosis may be associated with inhibition of liver collagen production.

Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts

To examine the role of gap junctions in cell senescence,the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts.Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43 protein distribution were done respectively. Furthermore,cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis. p53 gene expression level was detected with indirect immunofluorescence. We found that cisplatin (10 mM) treatment could block cell growth cycle at G1 and induced premature senescence. The premature senescence changes included high frequency of apoptosis,elevation of p53 expression,loss of membranous gap junctions and reduction of dye-transfer capacity. These changes were comparable to the changes of replicative senescence of human fibroblasts. It was also concluded that cisplatin could induce premature senescence concomitant with inhibition of gap junctions in the fibroblasts. Loss of functional gap junctions from the cell membrane may account for the reduced intercellular communication in the premature senescent fibroblasts. The cell system we used may provide a model useful for the study of the gap junction thus promoting agents against premature senescence.

Key players in pancreatic cancer-stroma interaction: cancer-associated fibroblasts, endothelial and inflammatory cells

Pancreatic cancer(PC) is the most aggressive type of common cancers, and in 2014, nearly 40000 patients died from the disease in the United States. Pancreatic ductal adenocarcinoma, which accounts for the majority of PC cases, is characterized by an intense stromal desmoplastic reaction surrounding the cancer cells. Cancer-associated fibroblasts(CAFs) are the main effector cells in the desmoplastic reaction, and pancreatic stellate cells are the most important source of CAFs. However, other important components of the PC stroma are inflammatory cells and endothelial cells. The aim of this review is to describe the complex interplay between PC cells and the cellular and noncellular components of the tumour stroma. Published data have indicated that the desmoplastic stroma protects PC cells against chemotherapy and radiation therapy and that it might promote the proliferation and migration of PC cells. However, in animal studies, experimental depletion of the desmoplastic stroma and CAFs has led to more aggressive cancers. Hence, the precise role of the tumour stroma in PC remains to be elucidated. However, it is likely that a contextdependent therapeutic modification, rather than pure depletion, of the PC stroma holds potential for the development of new treatment strategies for PC patients.

Mitomycin C induces apoptosis in human epidural scar fibroblasts after surgical decompression for spinal cord injury

Numerous studies have shown that topical application of mitomycin C after surgical decompression effectively reduces scar adhesion. However, the underlying mechanisms remain unclear. In this study, we investigated the effect of mitomycin C on the proliferation and apoptosis of human epidural scar fibroblasts. Human epidural scar fibroblasts were treated with various concentrations of mitomycin C （1, 5, 10, 20, 40 μg/mL） for 12, 24 and 48 hours. Mitomycin C suppressed the growth of these cells in a dose- and time-dependent manner. Mitomycin C upregulated the expression levels of Fas, DR4, DR5, cleaved caspase-8/9, Bax, Bim and cleaved caspase-3 proteins, and it downregulated Bcl-2 and Bcl-xL expression. In addition, inhibitors of caspase-8 and caspase-9 （Z-IETD-FMK and Z-LEHD-FMK, respectively） did not fully inhibit mitomycin C-induced apoptosis. Furthermore, mitomycin C induced endoplasmic reticulum stress by increasing the expression of glucose-regulated protein 78, CAAT/enhancer-binding protein homologous protein （CHOP） and caspase 4 in a dose-dependent manner. Salubrinal significantly inhibited the mitomycin C-induced cell viability loss and apoptosis, and these effects were accompanied by a reduction in CHOP expression. Our results support the hypothesis that mitomycin C induces human epidural scar fibroblast apoptosis, at least in part, via the endoplasmic reticulum stress pathway.

Cancer-associated fibroblasts in digestive tumors

The significant influence of tumor stroma on malignant cells has been extensively investigated in this era of targeted therapy. The tumor microenvironment, as a dynamic system, is orchestrated by various cells including tumor vascular composing cells, inflammatory cells and fibroblasts. As a major and important component in tumor stroma, increasing evidence has shown that spindle-shaped cancer-associated fibroblasts (CAFs) are a significant modifier of cancer evolution, and promote tumorigenesis, tumor invasion and metastasis by stimulating angiogenesis, malignant cell survival, epithelial-mesenchymal transition (EMT) and proliferation via direct cell-to-cell contact or secretion of soluble factors in most digestive solid tumors. CAFs are thought to be activated, characterized by the expression of &#x003b1;-smooth muscle actin, fibroblast activated protein, fibroblast specific protein, vimentin, fibronectin, etc. They are hypothesized to originate from normal or aged fibroblasts, bone marrow-derived mesenchymal cells, or vascular endothelial cells. EMT may also be an important process generating CAFs, and most probably, CAFs may originate from multiple cells. A close link exists between EMT, tumor stem cells, and chemo-resistance of tumor cells, which is largely orchestrated by CAFs. CAFs significantly induce immunosuppression, and may be a prognostic marker in various malignancies. Targeted therapy toward CAFs has displayed promising anticancer efficacy, which further reinforces the necessity to explore the relationship between CAFs and their hosts.

INFLUENCE OF QUERCETIN AND X-RAY ON COLLAGEN SYNTHESIS OF CULTURED HUMAN KELOID-DERIVED FIBROBLASTS

Objoctive To investigate the effects of quercetin and X-ray on collagen synthesis of cultured human keloid-derived fibroblast and the mechanism. Methods Collagen synthesis of cultured human keloid and normal fibroblasts were detected by hydroxyproline colorimetric analysis. Immunocytochemical staining was used to investigate collagen I and III expression, mRNA expression of collagen Ⅰ and Ⅲ, and transforming growth factor （ TGF）-β1 were assayed by reverse transcription-polymerase chain reaction （RT-PCR） and real-time PCR. Results Quercetin inhibited the collagen synthesis of both keloid and normal fibroblasts in a dose-dependent man- ner. Immunocytochemical staining indicated that collagenⅠ and Ⅲ were down-regulated by quercetin and X-ray （P 〈 0.05 ）, particularly collagen I （ P 〈 0. 05 ）. mRNA expression of both collagen I and III in quercetin groups significantly decreased compared with that in control group （ P 〈 0. 05 ）, especially in the group treated with both quercetin and X-ray （ P 〈 0. 01 ）. mRNA level of TGF-[31 gene was down-regulated by quercertin （ P 〈 0. 05 ）. Conclusions Quercetin will probably be one of the new medicines which could effectively treat keloid. Quercetin combined with X-ray could reduce the dose of radiation.