Kinome state is predictive of cell viability in pancreatic cancer tumor and cancer-associated fibroblast cell lines.

Numerous aspects of cellular signaling are regulated by the kinome-the network of over 500 protein kinases that guides and modulates information transfer throughout the cell. The key role played by both individual kinases and assemblies of kinases organized into functional subnetworks leads to kinome dysregulation driving many diseases, particularly cancer. In the case of pancreatic ductal adenocarcinoma (PDAC), a variety of kinases and associated signaling pathways have been identified for their key role in the establishment of disease as well as its progression. However, the identification of additional relevant therapeutic targets has been slow and is further confounded by interactions between the tumor and the surrounding tumor microenvironment. In this work, we attempt to link the state of the human kinome, or kinotype, with cell viability in treated, patient-derived PDAC tumor and cancer-associated fibroblast cell lines. We applied classification models to independent kinome perturbation and kinase inhibitor cell screen data, and found that the inferred kinotype of a cell has a significant and predictive relationship with cell viability. We further find that models are able to identify a set of kinases whose behavior in response to perturbation drive the majority of viability responses in these cell lines, including the understudied kinases CSNK2A1/3, CAMKK2, and PIP4K2C. We next utilized these models to predict the response of new, clinical kinase inhibitors that were not present in the initial dataset for model devlopment and conducted a validation screen that confirmed the accuracy of the models. These results suggest that characterizing the perturbed state of the human protein kinome provides significant opportunity for better understanding of signaling behavior and downstream cell phenotypes, as well as providing insight into the broader design of potential therapeutic strategies for PDAC.

Fibroblast-Derived Lysyl Oxidase Increases Oxidative Phosphorylation and Stemness in Cholangiocarcinoma.

BACKGROUND & AIMS: Metabolic and transcriptional programs respond to extracellular matrix-derived cues in complex environments, such as the tumor microenvironment. Here, we demonstrate how lysyl oxidase (LOX), a known factor in collagen crosslinking, contributes to the development and progression of cholangiocarcinoma (CCA). METHODS: Transcriptomes of 209 human CCA tumors, 143 surrounding tissues, and single-cell data from 30 patients were analyzed. The recombinant protein and a small molecule inhibitor of the LOX activity were used on primary patient-derived CCA cultures to establish the role of LOX in migration, proliferation, colony formation, metabolic fitness, and the LOX interactome. The oncogenic role of LOX was further investigated by RNAscope and in vivo using the AKT/NICD genetically engineered murine CCA model. RESULTS: We traced LOX expression to hepatic stellate cells and specifically hepatic stellate cell-derived inflammatory cancer-associated fibroblasts and found that cancer-associated fibroblast-driven LOX increases oxidative phosphorylation and metabolic fitness of CCA, and regulates mitochondrial function through transcription factor A, mitochondrial. Inhibiting LOX activity in vivo impedes CCA development and progression. Our work highlights that LOX alters tumor microenvironment-directed transcriptional reprogramming of CCA cells by facilitating the expression of the oxidative phosphorylation pathway and by increasing stemness and mobility. CONCLUSIONS: Increased LOX is driven by stromal inflammatory cancer-associated fibroblasts and correlates with diminished survival of patients with CCA. Modulating the LOX activity can serve as a novel tumor microenvironment-directed therapeutic strategy in bile duct pathologies.

Cyclooxygenases and Prostaglandins in Tumor Immunology and Microenvironment of Gastrointestinal Cancer.

Chronic inflammation is a known risk factor for gastrointestinal cancer. The evidence that nonsteroidal anti-inflammatory drugs suppress the incidence, growth, and metastasis of gastrointestinal cancer supports the concept that a nonsteroidal anti-inflammatory drug target, cyclooxygenase, and its downstream bioactive lipid products may provide one of the links between inflammation and cancer. Preclinical studies have demonstrated that the cyclooxygenase-2-prostaglandin E2 pathway can promote gastrointestinal cancer development. Although the role of this pathway in cancer has been investigated extensively for 2 decades, only recent studies have described its effects on host defenses against transformed epithelial cells. Overcoming tumor-immune evasion remains one of the major challenges in cancer immunotherapy. This review summarizes the impacts of the cyclooxygenase-2-prostaglandin E2 pathway on gastrointestinal cancer development. Our focus was to highlight recent advances in our understanding of how this pathway induces tumor immune evasion.

MMP1 drives tumor progression in large cell carcinoma of the lung through fibroblast senescence.

Large cell carcinoma (LCC) is a rare and aggressive lung cancer subtype with poor prognosis and no targeted therapies. Tumor-associated fibroblasts (TAFs) derived from LCC tumors exhibit premature senescence, and coculture of pulmonary fibroblasts with LCC cell lines selectively induces fibroblast senescence, which in turn drives LCC cell growth and invasion. Here we identify MMP1 as overexpressed specifically in LCC cell lines, and we show that expression of MMP1 by LCC cells is necessary for induction of fibroblast senescence and consequent tumor promotion in both cell culture and mouse models. We also show that MMP1, in combination with TGF-ß1, is sufficient to induce fibroblast senescence and consequent LCC promotion. Furthermore, we implicate PAR-1 and oxidative stress in MMP1/TGF-ß1-induced TAF senescence. Our results establish an entirely new role for MMP1 in cancer, and support a novel therapeutic strategy in LCC based on targeting senescent TAFs.

Inflammation-driven senescence-associated secretory phenotype in cancer-associated fibroblasts enhances peritoneal dissemination.

In the tumor microenvironment, senescent non-malignant cells, including cancer-associated fibroblasts (CAFs), exhibit a secretory profile under stress conditions; this senescence-associated secretory phenotype (SASP) leads to cancer progression and chemoresistance. However, the role of senescent CAFs in metastatic lesions and the molecular mechanism of inflammation-related SASP induction are not well understood. We show that pro-inflammatory cytokine-driven EZH2 downregulation maintains the SASP by demethylating H3K27me3 marks in CAFs and enhances peritoneal tumor formation of gastric cancer (GC) through JAK/STAT3 signaling in a mouse model. A JAK/STAT3 inhibitor blocks the increase in GC cell viability induced by senescent CAFs and peritoneal tumor formation. Single-cell mass cytometry revealed that fibroblasts exist in the ascites of GC patients with peritoneal dissemination, and the fibroblast population shows p16 expression and SASP factors at high levels. These findings provide insights into the inflammation-related SASP maintenance by histone modification and the role of senescent CAFs in GC peritoneal dissemination.

Prolonged treatment with Y-27632 promotes the senescence of primary human dermal fibroblasts by increasing the expression of IGFBP-5 and transforming them into a CAF-like phenotype.

The Rho-kinases (ROCK) inhibitor Y-27632 has been shown to promote the growth of epidermal cells, however, its potential effects on human dermal fibroblasts (HDFs) need to be clarified. Here we show that prolonged treatment of HDFs with Y-27632 decreased their growth by inducing senescence, which was associated with induction of the senescence markers p16 and p21, and downmodulation of the ERK pathways. The senescent HDFs induced by Y-27632 acquired a cancer-associated-fibroblast (CAF)-like phenotype to promote squamous cell carcinoma (SCC) cell growth in vitro. Expression of a newly identified target of Y-27632 by RNA-seq, insulin growth factor binding protein 5 (IGFBP-5), was dramatically increased after 24 h of treatment with Y-27632. Adding recombinant IGFBP-5 protein to the culture medium produced similar phenotypes of HDFs as did treatment with Y-27632, and knockdown of IGFBP-5 blocked the Y-27632-induced senescence. Furthermore, Y-27632 induced the expression of an IGFBP-5 upstream gene, GATA4, and knockdown of GATA4 also reduced the Y-27632-induced senescence. In summary, these results demonstrate for the first time that Y-27632 promotes cellular senescence in primary HDFs by inducing the expression of IGFBP-5 and that prolonged treatment with Y-27632 potentially transforms primary HDFs into CAF-like cells.

Cancer associated fibroblast FAK regulates malignant cell metabolism.

Emerging evidence suggests that cancer cell metabolism can be regulated by cancer-associated fibroblasts (CAFs), but the mechanisms are poorly defined. Here we show that CAFs regulate malignant cell metabolism through pathways under the control of FAK. In breast and pancreatic cancer patients we find that low FAK expression, specifically in the stromal compartment, predicts reduced overall survival. In mice, depletion of FAK in a subpopulation of CAFs regulates paracrine signals that increase malignant cell glycolysis and tumour growth. Proteomic and phosphoproteomic analysis in our mouse model identifies metabolic alterations which are reflected at the transcriptomic level in patients with low stromal FAK. Mechanistically we demonstrate that FAK-depletion in CAFs increases chemokine production, which via CCR1/CCR2 on cancer cells, activate protein kinase A, leading to enhanced malignant cell glycolysis. Our data uncover mechanisms whereby stromal fibroblasts regulate cancer cell metabolism independent of genetic mutations in cancer cells.

miR-210 transferred by lung cancer cell-derived exosomes may act as proangiogenic factor in cancer-associated fibroblasts by modulating JAK2/STAT3 pathway.

It has been generally believed that cancer-associated fibroblasts (CAFs) have the ability to increase the process of tumor angiogenesis. However, the potential mechanisms by which cancer-derived exosomes in lung cancer (LC) remains to be investigated. LC-derived exosomes were administrated to NIH/3T3 cells. A variety of experiments were conducted to investigate the proangiogenic factors of CAFs, including Western blot, RT-PCR, colony formation assay, tube formation assay, Matrigel plug assay et al. In addition, the impact of JAK2/STAT3 signaling pathway were also explored. The role of hsa-miR-210 was identified with microarray profiling and validated in vitro and in vivo assays. The target of miR-210 was screened by RNA pull down, RNA-sequencing and then verified. It was shown that LC-derived exosomes could induce cell reprogramming, thus promoting the fibroblasts transferring into CAFs. In addition, the exosomes with overexpressed miR-210 could increase the level of angiogenesis and vice versa, which suggested the miR-210 secreted by the LC-derived exosomes may initiate the CAF proangiogenic switch. According to our analysis, the miR-210 had the ability of elevating the expression of some proangiogenic factors such as MMP9, FGF2 and vascular endothelial growth factor (VEGF) a (VEGFa) by activating the JAK2/STAT3 signaling pathway, ten-eleven translocation 2 (TET2) was identified as the target of miR-210 in CAFs which has been involved in proangiogenic switch. miR-210 was overexpressed in serum exosomes of untreated non-small cell LC (NSCLC) patients. We concluded that the promotion effect of exosomal miR-210 on proangiogenic switch of CAFs may be explained by the modulation of JAK2/STAT3 signaling pathway and TET2 in recipient fibroblasts.

Lysyl oxidase promotes liver metastasis of gastric cancer via facilitating the reciprocal interactions between tumor cells and cancer associated fibroblasts.

BACKGROUND: Liver is one of the most preferred destinations of distant metastasis in gastric cancer (GC). As effective treatment is still limited, the prognosis of GC patients bearing liver metastasis is poor. We filter out lysyl oxidase (LOX) to study its function in the tumor microenvironment (TME) and seek for potential therapeutic targets. METHODS: Transcription analysis on 6 cases of liver metastasis of GC patients with respective paired primary tumors and adjacent normal livers was performed. The filtration out of LOX was done using 5 datasets. 69 GC liver metastasis tissues were utilized to perform immunohistochemistry (IHC) and analyze prognosis. Computed Tomography (CT) combined 3D organ reconstruction bioluminescence imaging was performed to precisely evaluate the metastatic tumor burden on liver of intrasplenic injection mouse model. Human and mouse cancer associated fibroblasts (CAFs) in liver metastasis were separated to culture to study the interaction of LOX and TGF-ß1. Patients-derived xenograft (PDX) model was established using liver metastasis of patients to evaluate the therapeutic value of LOX inhibitor ß-aminopropionitrile (BAPN). RESULTS: CAFs-derived LOX at liver metastatic niche of GC promotes niche formation and outgrowth thus predicts poor prognosis. Meanwhile tumor cells in niche secrete TGF-ß1 to nourish CAFs and stimulate them to produce more LOX in turn. The mechanism involved in LOX-mediated proliferation facilitation is enhancement of Warburg effect. The inhibitor of LOX, BPAN could hamper the effect brought by LOX in vivo and in vitro. INTERPRETATION: Our study has unveiled a positive feedback loop between CAFs and tumor cells in liver metastasis niche of GC. The core molecule is LOX which facilitates Warburg effect. Targeting LOX with its inhibitor BAPN might serve as a potential therapeutic strategy. FUND: This research was supported by the National Natural Science Foundation of China (31872740), the 100-member plan of the Shanghai Municipal Commission of Health and Family Planning (2017BR043), Shanghai Science and Technology Commission Project(17ZR1416800), Renji Hospital Training Fund (PYMDT-003, PYIII-17-015), National Natural Science Foundation of China (81672358), the Shanghai Municipal Education Commission-Gao feng Clinical MedicineGrant Support (20181708), Program of Shanghai Academic/Technology Research Leader(19XD1403400), Science and Technology Commission of Shanghai Municipality (18410721000), Shanghai Municipal Health Bureau (2018BR32), China Postdoctoral Science Foundation (2018M640403), National Natural Science Foundation of China (81701945) and Youth project of Shanghai Municipal Health Commission(20164Y0045).

Exosomal miRNA-139 in cancer-associated fibroblasts inhibits gastric cancer progression by repressing MMP11 expression.

Solid tumors consist of various types of stromal cells in addition to cancer cells. Cancer-associated fibroblasts (CAFs) are a major component of the tumor stroma and play an essential role in tumor progression and metastasis in a variety of malignancies, including gastric cancer. However, the effects of CAFs on gastric cancer cells' progression and metastasis are not well studied. Here we show that matrix metalloproteinase 11 (MMP11) in exosomes secreted from CAFs can be delivered into gastric cancer cells. Gastric CAFs promote gastric cancer cell migration partially through exosomal MMP11. Moreover, MMP11 is overexpressed in exosomes purified from plasma of gastric cancer patients and tumor tissues and associated with overall survival of gastric patients. We also find that MMP11 is negatively regulated by exosomal miR-139 in the CAFs of gastric cancer. Exosomal miR-139 inhibits tumor growth and metastasis of gastric cancer cells by decreasing the expression of MMP11 in vitro and in vivo. Thus, we propose that exosomal miR-139 derived from gastric CAFs could inhibit the progression and metastasis of gastric cancer by decreasing MMP11 in tumor microenvironment.

Upregulated NOX1 expression in gallbladder cancer­associated fibroblasts predicts a poor prognosis.

Gallbladder cancer (GBC) is a lethal aggressive malignant neoplasm of the biliary tract. Potential prognostic markers and therapeutic targets for this disease are urgently required. Cancer­associated fibroblasts (CAFs) play a key role in tumorigenesis and the development of cancer. Nicotinamide adenine dinucleotide phosphate oxidase 1 (NOX1) expression has been reported to be involved in tumorigenesis and useful for tumor prognosis. However, NOX1 expression in the stroma of GBCs, particularly gallbladder cancer­associated fibroblasts (GCAFs), and its prognostic significance in GBC patients remains unclear. In the present study, NOX1 expression in the stroma of human gallbladder lesions in vivo was investigated, as well as in GCAFs and co­cultures of GBC­SD+GCAFs in vitro, and their correlation with clinicopathological parameters and the prognosis of GBC patients were evaluated. The results revealed that NOX1 expression was significantly upregulated in the stroma of GBCs compared with precancerous and benign lesions of the gallbladder; NOX1 expression was localized to gallbladder stromal fibroblasts expressing α­smooth muscle actin and fibroblast secreted protein­1. Furthermore, these observations were confirmed by the fact that NOX1 expression was upregulated in GCAFs as determined by Affymetrix gene profile chip analysis and reverse transcription­quantitative PCR. In addition, overexpression was observed in formed spheroids of GBC­SD+GCAF co­cultures by immunohistochemistry and western blotting in vitro. Thus, it was verified that NOX1 expression was upregulated in GCAFs. Furthermore, upregulated stromal NOX1 expression was correlated with aggressive characteristics such as differentiation degree (P=0.042), venous invasion (P=0.041), resection methods (P=0.002), and a lower survival rate (P=0.025, log­rank test) of patients with GBC. Stromal NOX1 expression (P=0.047) was an independent prognostic factor for the overall survival rate of patients with GBC. GBC patients with upregulated NOX1 expression in GCAFs had a poorer prognosis. These results revealed that stromal NOX1 may be a novel biomarker and/or target, and may contribute to the discovery of new tumor markers and potential targeted therapeutics for human GBCs.

Effect of FGF/FGFR pathway blocking on lung adenocarcinoma and its cancer-associated fibroblasts.

Cancer-associated fibroblasts (CAFs) are known to promote tumourigenesis through various mechanisms. Fibroblast growth factor (FGF)/FGF receptor (FGFR)-dependent lung cancers have been described. We have developed a mouse model of lung adenocarcinoma that was constructed through the induction of Fgf9 overexpression in type 2 alveolar cells. The expression of Fgf9 in adult lungs resulted in the rapid development of multiple adenocarcinoma-like tumour nodules. Here, we have characterised the contribution of CAFs and the Fgf/Fgfr signalling pathway in maintaining the lung tumours initiated by Fgf9 overexpression. We found that CAF-secreted Fgf2 contributes to tumour cell growth. CAFs overexpressed Tgfb, Mmp7, Fgf9, and Fgf2; synthesised more collagen, and secreted inflammatory cell-recruiting cytokines. CAFs also enhanced the conversion of tumour-associated macrophages (TAMs) to the tumour-supportive M2 phenotype but did not influence angiogenesis. In vivo inhibition of Fgfrs during early lung tumour development resulted in significantly smaller and fewer tumour nodules, whereas inhibition in established lung tumours caused a significant reduction in tumour size and number. Fgfr inhibition also influenced tumour stromal cells, as it significantly abolished TAM recruitment and reduced tumour vascularity. However, the withdrawal of the inhibitor caused a significant recurrence/regrowth of Fgf/Fgfr-independent lung tumours. These recurrent tumours did not possess a higher proliferative or propagative potential. Our results provide evidence that fibroblasts associated with the Fgf9-induced lung adenocarcinoma provide multiple means of support to the tumour. Although the Fgfr blocker significantly suppressed the tumour and its stromal cells, it was not sufficient to completely eliminate the tumour, probably due to the emergence of alternative (resistance/maintenance) mechanism(s). This model represents an excellent tool to further study the complex interactions between CAFs, their related chemokines, and the progression of lung adenocarcinoma; it also provides further evidence to support the need for a combinatorial strategy to treat lung cancer. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Proteomics reveals NNMT as a master metabolic regulator of cancer-associated fibroblasts.

High-grade serous carcinoma has a poor prognosis, owing primarily to its early dissemination throughout the abdominal cavity. Genomic and proteomic approaches have provided snapshots of the proteogenomics of ovarian cancer1,2, but a systematic examination of both the tumour and stromal compartments is critical in understanding ovarian cancer metastasis. Here we develop a label-free proteomic workflow to analyse as few as 5,000 formalin-fixed, paraffin-embedded cells microdissected from each compartment. The tumour proteome was stable during progression from in situ lesions to metastatic disease; however, the metastasis-associated stroma was characterized by a highly conserved proteomic signature, prominently including the methyltransferase nicotinamide N-methyltransferase (NNMT) and several of the proteins that it regulates. Stromal NNMT expression was necessary and sufficient for functional aspects of the cancer-associated fibroblast (CAF) phenotype, including the expression of CAF markers and the secretion of cytokines and oncogenic extracellular matrix. Stromal NNMT expression supported ovarian cancer migration, proliferation and in vivo growth and metastasis. Expression of NNMT in CAFs led to depletion of S-adenosyl methionine and reduction in histone methylation associated with widespread gene expression changes in the tumour stroma. This work supports the use of ultra-low-input proteomics to identify candidate drivers of disease phenotypes. NNMT is a central, metabolic regulator of CAF differentiation and cancer progression in the stroma that may be therapeutically targeted.

Cyclooxygenase-2 in cancer: A review.

Cyclooxygenase-2 (COX-2) is frequently expressed in many types of cancers exerting a pleiotropic and multifaceted role in genesis or promotion of carcinogenesis and cancer cell resistance to chemo- and radiotherapy. COX-2 is released by cancer-associated fibroblasts (CAFs), macrophage type 2 (M2) cells, and cancer cells to the tumor microenvironment (TME). COX-2 induces cancer stem cell (CSC)-like activity, and promotes apoptotic resistance, proliferation, angiogenesis, inflammation, invasion, and metastasis of cancer cells. COX-2 mediated hypoxia within the TME along with its positive interactions with YAP1 and antiapoptotic mediators are all in favor of cancer cell resistance to chemotherapeutic drugs. COX-2 exerts most of the functions through its metabolite prostaglandin E2. In some and limited situations, COX-2 may act as an antitumor enzyme. Multiple signals are contributed to the functions of COX-2 on cancer cells or its regulation. Members of mitogen-activated protein kinase (MAPK) family, epidermal growth factor receptor (EGFR), and nuclear factor-κß are main upstream modulators for COX-2 in cancer cells. COX-2 also has interactions with a number of hormones within the body. Inhibition of COX-2 provides a high possibility to exert therapeutic outcomes in cancer. Administration of COX-2 inhibitors in a preoperative setting could reduce the risk of metastasis in cancer patients. COX-2 inhibition also sensitizes cancer cells to treatments like radio- and chemotherapy. Chemotherapeutic agents adversely induce COX-2 activity. Therefore, choosing an appropriate chemotherapy drugs along with adjustment of the type and does for COX-2 inhibitors based on the type of cancer would be an effective adjuvant strategy for targeting cancer.

Phospholipase D activation mediates growth and migration of colon cancer cells interacting with cancer-associated fibroblasts.

Cancer-associated fibroblasts of the stroma play a major role in tumor promoting processes. In this study we evaluated the significance of Phospholipase D (PLD) enzyme activity in promoting human colon cancer malignant potency when interacting with proximal colonic fibroblasts. Human colon cancer cell lines SW480 and HCT116, and colonic fibroblasts CCD-18Co were used as an in vitro model. PLD's activity was measured in resting cancer cells and after culturing with fibroblasts and cancer-associated fibroblasts (CAFs) conditioned medium. The viability and migration level of the cancer cells alone and after co-culturing with fibroblast or CAFs conditioned medium were evaluated, with and without adding a PLD inhibitor. Exposure of colon cancer cells to CAFs conditioned medium significantly increased the level of PLD activity in the cancer cells (p<0.0001). Exposure of colon cancer to resting and activated fibroblast conditioned medium significantly enhanced the number of viable cancer cells as well as its migration level measured following 24 and 48 hours. Adding a PLD inhibitor significantly reduced the elevation of cell viability and migration of the colon cancer cells exposed to fibroblasts conditioned medium (p<0.005). In this in vitro model, inhibition of PLD significantly decreased proliferation and migration levels of colon cancer cells generated by stromal fibroblasts. This provides evidence that the PLD signaling pathway is directly involved in stroma-cancer interactions in the colon, thereby promoting cancer progression. Further research is needed in order to evaluate PLD as a target in colon cancer prevention or therapy.

Histone deacetylase 6 regulates the immunosuppressive properties of cancer-associated fibroblasts in breast cancer through the STAT3-COX2-dependent pathway.

Cancer-associated fibroblasts (CAFs) are important components in breast tumors and essential for tumor progression and metastasis. However, the role of epigenetic modification in driving the function of CAFs within breast tumors is only marginally known. Herein, we reported that histone deacetylase 6 (HDAC6), one of class II histone deacetylases, was frequently upregulated in the CAFs of breast tumor and promotes an immunosuppressive microenvironment. The genetic or pharmacologic disruption of HDAC6 in CAFs delays tumor growth, inhibits the tumor recruitment of myeloid-derived suppressor cells and regulatory T cells, alters the macrophage phenotype switch, and increases the CD8+ and CD4+ T-cell activation in vivo. Mechanistically, we identified prostaglandin E2/cyclooxygenase-2 (COX2) as a major target of HDAC6 in CAFs by regulating STAT3 activation. Overexpressing COX2 in HDAC6-knockdown CAFs can completely restore the immunosuppressive properties of the fibroblasts. Clinically, a positive correlation among the stromal expression levels of HDAC6, p-STAT3, and COX2 in human breast cancer was observed. High-stromal expression of HDAC6 was markedly associated with poor survival outcome. Overall, our findings indicated that fibroblastic HDAC6 was a vital epigenetic mediator involved in programming an immunosuppressive tumor microenvironment that dampens antitumor immunity. Thus, HDAC6 may be a good potential target to improve breast cancer immunotherapy.

Isolation of Fibroblast-Activation Protein-Specific Cancer-Associated Fibroblasts.

The current study is to develop a gentle and efficient method for purification of fibroblast-activation protein positive (FAP+) cancer-associated fibroblasts (CAFs) from tumor tissues. Fresh tissues were isolated from BALB/c-Nude mice bearing human liver cancer cell line (HepG2), fully minced and separated into three parts, and digested with trypsin digestion and then treated with collagenase type IV once, twice, or thrice, respectively. Finally, the cells were purified by using FAP magnetic beads. The isolated CAFs were grown in culture medium and detected for the surface expression of fibroblast-activation protein (FAP). The number of adherent cells which were obtained by digestion process with twice collagenase type IV digestion was (5.99 ± 0.18) × 104, much more than that with the only once collagenase type IV digestion (2.58 ± 0.41) × 104 (P < 0.0001) and similar to thrice collagenase type IV digestion. The percentage of FAP+ CAFs with twice collagenase type IV digestion (38.5%) was higher than that with the only once collagenase type IV digestion (20.0%) and little higher than thrice collagenase type IV digestion (37.5%). The FAP expression of CAFs was quite different from normal fibroblasts (NFs). The fibroblasts isolated by the innovation are with high purity and being in wonderful condition and display the features of CAFs.

Aberrant low expression of p85α in stromal fibroblasts promotes breast cancer cell metastasis through exosome-mediated paracrine Wnt10b.

P85α, which acts as a tumour suppressor, is frequently found to be downregulated in various human cancers. However, the role of p85α in the tumour microenvironment is unknown. Here, we report that aberrantly low expression of p85α in breast cancer stroma is clinically relevant to breast cancer disease progression. Stromal fibroblasts can acquire the hallmarks of cancer-associated fibroblasts (CAFs) as a result of the loss of p85α expression. Paracrine Wnt10b from p85α-deficient fibroblasts can promote cancer progression via epithelial-to-mesenchymal transition (EMT) induced by the canonical Wnt pathway. Moreover, exosomes have a key role in paracrine Wnt10b transport from fibroblasts to breast cancer epithelial cells. Our results reveal that p85α expression in stromal fibroblasts haves a crucial role in regulating breast cancer tumourigenesis and progression by modifying stromal-epithelial crosstalk and remodelling the tumour microenvironment. Therefore, p85α can function as a tumour suppressor and represent a new candidate for diagnosis, prognosis and targeted therapy.

Cancer-associated fibroblasts enhance pancreatic cancer cell invasion by remodeling the metabolic conversion mechanism.

We investigated the mechanism of cancer-associated fibroblasts (CAFs) in promoting the invasion and metastasis of pancreatic cancer cells in a non-vascular manner. We verified the original generation of isolated cultured CAFs and normal fibroblasts (NFs) based on the expression of α-SMA and vimentin, and we examined the cell glycolysis level through glucose consumption and lactate production experiments. The mRNA and protein expression of CAF glycolytic enzymes, lactate dehydrogenase and pyruvate kinase m2, were examined by RT-PCR and western blotting, respectively. In vitro culture first-generation pancreatic CAFs were collected and cultured together with pancreas cancer BxPc-3 and Panc-1 cells. Cell invasion and migration were assessed using a Transwell assay and scratch test, respectively. Mitochondrial activity was assessed by experimentally determining oxidative phosphorylation (OP) activity. The aerobic oxidation index of cancer cells was also examined. Succinate dehydrogenase, fumarate hydratase (FH), and monocarboxylate transporter 1 (MCT1) expression were examined using an MCT1-specific inhibitor to remove 'tumor-stromal' metabolic coupling to observe the influence of cell interstices on pancreas cancer progression. First-generation isolated cultured CAFs and NFs both grew well, and showed active proliferation. Glucose absorption and lactate production were significantly enhanced in CAFs compared with that in NFs. PCR and western blotting showed that the lactate dehydrogenase and pyruvate kinase m2 mRNA and protein expression levels were increased in the CAFs. After indirect co-culture, OP was increased in the BxPc-3 and Panc-1 cells; correspondingly, succinate dehydrogenase, FH and MCT expression were increased. After the MCT1-specific inhibitor removed 'tumor-stromal' metabolic coupling, the migration and invasion abilities of the pancreatic cancer cells were decreased. Pancreatic CAFs can alter metabolism as well as communicate with and respond to cancer cell migration and invasion. This may be an important mechanism for promoting tumor progression in a non-vascular manner in the tumor microenvironment. The mechanism by which CAFs reshape metabolic transition requires further analysis.

Inhibitors of Rho kinase (ROCK) signaling revert the malignant phenotype of breast cancer cells in 3D context.

Loss of polarity and quiescence along with increased cellular invasiveness are associated with breast tumor progression. ROCK plays a central role in actin-cytoskeletal rearrangement. We used physiologically relevant 3D cultures of nonmalignant and cancer cells in gels made of laminin-rich extracellular matrix, to investigate ROCK function. Whereas expression levels of ROCK1 and ROCK2 were elevated in cancer cells compared to nonmalignant cells, this was not observed in 2D cultures. Malignant cells showed increased phosphorylation of MLC, corresponding to disorganized F-actin. Inhibition of ROCK signaling restored polarity, decreased disorganization of F-actin, and led to reduction of proliferation. Inhibition of ROCK also decreased EGFR and Integrinß1 levels, and consequently suppressed activation of Akt, MAPK and FAK as well as GLUT3 and LDHA levels. Again, ROCK inhibition did not inhibit these molecules in 2D. A triple negative breast cancer cell line, which lacks E-cadherin, had high levels of ROCK but was less sensitive to ROCK inhibitors. Exogenous overexpression of E-cadherin, however, rendered these cells strikingly sensitive to ROCK inhibition. Our results add to the growing literature that demonstrate the importance of context and tissue architecture in determining not only regulation of normal and malignant phenotypes but also drug response.