CT45A1-mediated MLC2 (MYL9) phosphorylation promotes natural killer cell resistance and outer cell fate in a cell-in-cell structure, potentiating the progression of microsatellite instability-high colorectal cancer.

Patients with microsatellite instability-high (MSI-H) colorectal cancer (CRC) have high tumor mutation burden and tumor immunogenicity, exhibiting a higher response rate to immunotherapy and better survival. However, a portion of MSI-H CRC patients still experience adverse disease outcomes. We aimed to identify the tumor-autonomous regulators determining these heterogeneous clinical outcomes. The Cancer Genome Atlas (TCGA) dataset was used to identify regulators in MSI-H CRC patients with unfavorable outcomes. Stable CRC tumor clones expressing targeted regulators were established to evaluate migratory and stemness properties, immune cell vulnerability, and cell-in-cell (CIC) structure formation. RNA-sequencing (RNA-seq) was used to identify enriched biological pathways in stable CRC tumor clones. Clinicopathological characterization of formalin-fixed paraffin-embedded (FFPE) MSI-H CRC specimens was performed to explore the underlying mechanisms involved. We showed that cancer/testis antigen family 45 member A1 (CT45A1) expression was upregulated in MSI-H CRC patients with poor survival outcomes. CT45A1-expressing microsatellite stable (MSS) CRC cells showed enhanced migratory ability. However, CT45A1-expressing MSI-H CRC cells, but not MSS CRC cells, showed higher resistance to natural killer (NK) cell cytotoxicity and served as outer cells in homotypic CIC structures, preventing exogenous or therapeutic antibody access to inner CRC cells. Inactivating RHO-ROCK/MLCK-MLC2 signaling with small-molecule inhibitors or short-hairpin RNAs (shRNAs) targeting myosin light chain kinase (MYLK) abolished NK cell resistance and reduced the outer cell fate of CT45A1-expressing MSI-H CRC cells. In MSI-H CRC patients, CT45A1-positive tumors exhibited increased MLC2 phosphorylation, increased outer cell fate, and decreased survival. We demonstrated that CT45A1 potentiates the advanced progression of MSI-H CRC, and targeting MLC2 phosphorylation may enhance immunotherapy efficacy in CT45A1-positive MSI-H CRC patients.

PPIH as a poor prognostic factor increases cell proliferation and m6A RNA methylation in hepatocellular carcinoma.

RNA-binding proteins (RBPs) play a crucial role in the biological processes of liver hepatocellular carcinoma (LIHC). Peptidyl-prolyl cis-trans isomerase H (PPIH), an RBP, possesses prolyl isomerase activity and functions as a protein chaperone. The relationship between PPIH and LIHC has not yet been fully elucidated. This study elucidated potential mechanisms through which PPIH affects the prognosis of LIHC. Bioinformatics analysis and in vitro experiments revealed that PPIH expression was higher in LIHC tissues than in normal tissues. PPIH was identified as an independent prognostic factor, with high PPIH expression being associated with worse prognoses. Moreover, PPIH increased the m6A RNA methylation level and promoted cell proliferation by modulating DNA replication and the expression of cell cycle-related genes in LIHC cells. Bioinformatics analysis also revealed that PPIH expression increased immune cell infiltration and the expression of immune checkpoint proteins. Collectively, these findings indicate that PPIH might promote LIHC progression by enhancing the m6A RNA methylation level, increasing cell proliferation, and altering the tumor immune microenvironment. Our study demonstrates that PPIH, as a poor prognostic factor, may lead to LIHC malignancy through multiple pathways. Further in-depth research on this topic is warranted.

Ganoderma microsporum immunomodulatory protein combined with KRASG12C inhibitor impedes intracellular AKT/ERK network to suppress lung cancer cells with KRAS mutation.

KRAS mutations are tightly associated with lung cancer progression. Despite the unprecedented clinical success of KRASG12C inhibitors, recurrent mechanisms of resistance and other KRAS mutations require further therapeutic approaches. GMI, a protein from the medicinal mushroom Ganoderma microsporum, possesses antitumor activity; whereas, the biological function of GMI on regulating KRAS mutant lung cancer cells remains unknown. Herein, RNA-sequencing and bioinformatics showed that GMI may regulate KRAS-modulated MAPK and PI3K-AKT pathways in A549 (KRASG12S) cells. Further experiments demonstrated that GMI inhibited KRAS activation and suppressed ERK1/2 and AKT signaling in A549 cells. Intriguingly, GMI inhibited AKT signaling but increased phosphorylation of ERK in H358 (KRASG12C) cells. GMI significantly suppressed tumor growth in LLC1 cells-allograft and H358 cells-xenograft mice. GMI showed a synergistic effect with KRASG12C inhibitors in inhibiting cell growth, KRAS activation and KRAS-mediated downstream signaling, leading to apoptosis in H358 cells. Combination of GMI and KRASG12C inhibitor, AMG 510, resulted in more durable inhibition of tumor growth and KRAS activity in H358 cells-xenograft mice. This study highlights the potential of GMI, a dietary fungal protein, as a viable therapeutic avenue for KRAS-mutant lung cancer in combination with KRASG12C inhibitors.

Haematopoietic cell-derived exosomes in cancer development and therapeutics: From basic science to clinical practice.

BACKGROUND: The tumour microenvironment (TME) is a specialised niche involving intercellular communication among cancer cells and various host cells. Among the host cells, the quantity and quality of immune cells within the TME play essential roles in cancer development and management. The immunologically suppressive, so-called 'cold' TME established by a series of tumour-host interactions, including generating immunosuppressive cytokines and recruiting regulatory host immune cells, is associated with resistance to therapies and worse clinical outcomes. MAIN BODY: Various therapeutic approaches have been used to target the cold TME, including immune checkpoint blockade therapy and adoptive T-cell transfer. A promising, less explored therapeutic strategy involves targeting TME-associated exosomes. Exosomes are nanometer-sized, extracellular vesicles that transfer material from donor to recipient cells. These particles can reprogram the recipient cells and modulate the TME. In particular, exosomes from haematopoietic cells are known to promote or suppress cancer progression under specific conditions. Understanding the effects of haematopoietic cell-secreted exosomes may foster the development of therapeutic exosomes (tExos) for personalised cancer treatment. However, the development of exosome-based therapies has unique challenges, including scalable production, purification, storage and delivery of exosomes and controlling batch variations. Clinical trials are being conducted to verify the safety, feasibility, availability and efficacy of tExos. CONCLUSION: This review summarises our understanding of how haematopoietic cell-secreted exosomes regulate the TME and antitumour immunity and highlights present challenges and solutions for haematopoietic cell-derived exosome-based therapies.

Ganoderma microsporum immunomodulatory protein as an extracellular epidermal growth factor receptor (EGFR) degrader for suppressing EGFR-positive lung cancer cells.

Epidermal growth factor receptor (EGFR) abnormalities relevant to tumor progression. A newly developed strategy for cancer therapy is induction of EGFR degradation. GMI, an immunomodulatory protein from the medicinal mushroom Ganoderma microsporum, exhibits anticancer activity. However, its role in the intracellular trafficking and degradation of EGFR remains unclear. In this study, we discovered that GMI inhibits the phosphorylation of multiple tyrosine kinases. Specifically, GMI was discovered to suppress lung cancer cells harboring both wild-type and mutant EGFR by inhibiting EGFR dimerization and eliminating EGFR-mediated signaling. Functional studies revealed that GMI binds to the extracellular segment of EGFR. GMI interacts with EGFR to induce phosphorylation of EGFR at tyrosine1045, which triggers clathrin-dependent endocytosis and degradation of EGFR. Furthermore, in the mouse models, GMI was discovered to suppress tumor growth. Knockdown of EGFR in lung cancer cells abolishes GMI's anticancer activity in vivo and in vitro. Our results reveal the interaction mechanisms through which GMI induces EGFR degradation and abolishes EGFR-mediated intracellular pathway. Our study indicates that GMI is an EGFR degrader for inhibiting EGFR-expressing tumor growth.

T-cell exhaustion and stemness in antitumor immunity: Characteristics, mechanisms, and implications.

T cells play a crucial role in the regulation of immune response and are integral to the efficacy of cancer immunotherapy. Because immunotherapy has emerged as a promising treatment for cancer, increasing attention has been focused on the differentiation and function of T cells in immune response. In this review, we describe the research progress on T-cell exhaustion and stemness in the field of cancer immunotherapy and summarize advances in potential strategies to intervene and treat chronic infection and cancer by reversing T-cell exhaustion and maintaining and increasing T-cell stemness. Moreover, we discuss therapeutic strategies to overcome T-cell immunodeficiency in the tumor microenvironment and promote continuous breakthroughs in the anticancer activity of T cells.

Molecular actions of exosomes and their theragnostics in colorectal cancer: current findings and limitations.

Extracellular vesicles (EVs) are cell-released, membranous structures essential for intercellular communication. The biochemical compositions and physiological impacts of exosomes, lipid-bound, endosomal origin EVs, have been focused on, especially on the tumor-host interactions in a defined tumor microenvironment (TME). Despite recent progress in targeted therapy and cancer immunotherapy in colorectal cancer (CRC), cancer patients still suffer from distal metastasis and tumor relapse, suggesting unmet needs for biomarkers directing therapeutic interventions and predicting treatment responsiveness. As exosomes are indispensable for intercellular communication and high exosome abundance makes them feasible biomarker molecules, this review discusses exosome heterogeneity and how exosomes orchestrate the interplay among tumor cells, cancer stem cells (CSCs) and host cells, including stromal cells, endothelial cells and immunocytes, in the CRC TME. This review also discusses mechanisms for loading exosomal contents and potential exosomal DNA, RNA and protein biomarkers for early CRC detection. Finally, we summarize the diagnostic and therapeutic exosomes in clinical trials. We envision that detecting and targeting cancer-specific exosomes could provide therapeutic advances in developing personalized cancer medicine.

Characterization of Collapsin Response Mediator Protein 2 in Colorectal Cancer Progression in Subjects with Diabetic Comorbidity.

BACKGROUND: Common demographic risk factors are identified in colorectal cancer (CRC) and type 2 diabetes mellitus (DM), nevertheless, the molecular link and mechanism for CRC-DM comorbidity remain elusive. Dysregulated glycogen synthase kinase-3 beta under metabolic imbalance is suggested to accelerate CRC pathogenesis/progression via regulating collpasin response mediator protein-2 (CRMP2). Accordingly, roles of CRMP2 in CRC and CRC-DM patients were investigated for elucidating the molecular convergence of CRC and DM. METHODS: CRMP2 profile in tumor tissues from CRC and CRC-DM patients was investigated to explore the link between CRC and DM etiology. Meanwhile, molecular mechanism of glucose to regulate CRMP2 profile and CRC characteristics was examined in vitro and in vivo. RESULTS: CRMP2 was significantly lower in tumor lesions and associated with advanced tumor stage in CRC-DM patients. Physiological hyperglycemia suppressed CRMP2 expression/activity and augmented malignant characteristics of CRC cells. Hyperglycemia promotes actin de-polymerization, cytoskeleton flexibility and cell proliferation/metastasis by downregulating CRMP2 profile and thus contributes to CRC disease progression. CONCLUSIONS: This study uncovers molecular evidence to substantiate and elucidate the link between CRC and T2DM, as well as characterizing the roles of CRMP2 in CRC-DM. Accordingly, altered metabolic adaptations are promising targets for anti-diabetic and cancer strategies.

Curcumin Suppresses TGF-ß1-Induced Myofibroblast Differentiation and Attenuates Angiogenic Activity of Orbital Fibroblasts.

Orbital fibrosis, a hallmark of tissue remodeling in Graves' ophthalmopathy (GO), is a chronic, progressive orbitopathy with few effective treatments. Orbital fibroblasts are effector cells, and transforming growth factor ß1 (TGF-ß1) acts as a critical inducer to promote myofibroblast differentiation and subsequent tissue fibrosis. Curcumin is a natural compound with anti-fibrotic activity. This study aims to investigate the effects of curcumin on TGF-ß1-induced myofibroblast differentiation and on the pro-angiogenic activities of orbital fibroblasts. Orbital fibroblasts from one healthy donor and three patients with GO were collected for primary cell culture and subjected to myofibroblast differentiation under the administration of 1 or 5 ng/mL TGF-ß1 for 24 h. The effects of curcumin on TGF-ß1-induced orbital fibroblasts were assessed by measuring the cellular viability and detecting the expression of myofibroblast differentiation markers, including connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA). The pro-angiogenic potential of curcumin-treated orbital fibroblasts was evaluated by examining the transwell migration and tube-forming capacities of fibroblast-conditioned EA.hy926 and HMEC-1 endothelial cells. Treatment of orbital fibroblasts with curcumin inhibited the TGF-ß1 signaling pathway and attenuated the expression of CTGF and α-SMA induced by TGF-ß1. Curcumin, at the concentration of 5 µg/mL, suppressed 5 ng/mL TGF-ß1-induced pro-angiogenic activities of orbital fibroblast-conditioned EA hy926 and HMEC-1 endothelial cells. Our findings suggest that curcumin reduces the TGF-ß1-induced myofibroblast differentiation and pro-angiogenic activity in orbital fibroblasts. The results support the potential application of curcumin for the treatment of GO.

Insulin-Like Growth Factor 2 mRNA-Binding Protein 1 (IGF2BP1) Is a Prognostic Biomarker and Associated with Chemotherapy Responsiveness in Colorectal Cancer.

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is an RNA-binding protein and serves as a post-transcriptional fine-tuner regulating the expression of mRNA targets. However, the clinicopathological roles of IGF2BP1 in colorectal cancer (CRC) remains limited. Thus, we aimed to elucidate the clinical significance and biomarker potentials of IGF2BP1 in CRC. A total of 266 specimens from two sets of CRC patients were collected. IGF2BP1 expression was studied by immunohistochemical (IHC) staining. The Kaplan-Meier survival plot and a log-rank test were used for survival analysis. The Cox proportional hazards model was applied to determine the survival impact of IGF2BP1. Public datasets sets from The Cancer Genome Atlas (TCGA) and Human Cancer Metastasis Database (HCMDB), receiver operating characteristic (ROC) plotter, and two CRC cell lines, HCT-116 and DLD-1, were used for validating our findings. We showed that IGF2BP1 was overexpressed in tumor specimens compared to 13 paired normal parts by examining the immunoreactivity of IGF2BP1 (p = 0.045). The increased expression of IGF2BP1 in primary tumor parts was observed regardless of metastatic status (p < 0.001) in HCMDB analysis. IGF2BP1 expression was significantly associated with young age (59.6% vs. 46.7%, p-value = 0.043) and advanced stage (61.3% vs. 40.0%, p-value = 0.001). After controlling for confounding factors, IGF2BP1 remained an independent prognostic factor (HR = 1.705, p-value = 0.005). TCGA datasets analysis indicated that high IGF2BP1 expression showed a lower 5-year survival rate (58% vs. 65%) in CRC patients. The increased expression of IGF2BP1 in chemotherapy non-responder rectal cancer patients was observed using a ROC plotter. Overexpression of IGF2BP1 promoted the colony-forming capacity and 5-fluorouracil and etoposide resistance in CRC cells. Here, IGF2BP1 was an independent poor prognostic marker in CRC patients and contributed to aggressive phenotypes in CRC cell lines.

Human ribonuclease 1 serves as a secretory ligand of ephrin A4 receptor and induces breast tumor initiation.

Human ribonuclease 1 (hRNase 1) is critical to extracellular RNA clearance and innate immunity to achieve homeostasis and host defense; however, whether it plays a role in cancer remains elusive. Here, we demonstrate that hRNase 1, independently of its ribonucleolytic activity, enriches the stem-like cell population and enhances the tumor-initiating ability of breast cancer cells. Specifically, secretory hRNase 1 binds to and activates the tyrosine kinase receptor ephrin A4 (EphA4) signaling to promote breast tumor initiation in an autocrine/paracrine manner, which is distinct from the classical EphA4-ephrin juxtacrine signaling through contact-dependent cell-cell communication. In addition, analysis of human breast tumor tissue microarrays reveals a positive correlation between hRNase 1, EphA4 activation, and stem cell marker CD133. Notably, high hRNase 1 level in plasma samples is positively associated with EphA4 activation in tumor tissues from breast cancer patients, highlighting the pathological relevance of the hRNase 1-EphA4 axis in breast cancer. The discovery of hRNase 1 as a secretory ligand of EphA4 that enhances breast cancer stemness suggests a potential treatment strategy by inactivating the hRNase 1-EphA4 axis.

The microRNA-210-Stathmin1 Axis Decreases Cell Stiffness to Facilitate the Invasiveness of Colorectal Cancer Stem Cells.

Cell migration is critical for regional dissemination and distal metastasis of cancer cells, which remain the major causes of poor prognosis and death in patients with colorectal cancer (CRC). Although cytoskeletal dynamics and cellular deformability contribute to the migration of cancer cells and metastasis, the mechanisms governing the migratory ability of cancer stem cells (CSCs), a nongenetic source of tumor heterogeneity, are unclear. Here, we expanded colorectal CSCs (CRCSCs) as colonospheres and showed that CRCSCs exhibited higher cell motility in transwell migration assays and 3D invasion assays and greater deformability in particle tracking microrheology than did their parental CRC cells. Mechanistically, in CRCSCs, microRNA-210-3p (miR-210) targeted stathmin1 (STMN1), which is known for inducing microtubule destabilization, to decrease cell elasticity in order to facilitate cell motility without affecting the epithelial-mesenchymal transition (EMT) status. Clinically, the miR-210-STMN1 axis was activated in CRC patients with liver metastasis and correlated with a worse clinical outcome. This study elucidates a miRNA-oriented mechanism regulating the deformability of CRCSCs beyond the EMT process.

Roles of microRNAs in Regulating Cancer Stemness in Head and Neck Cancers.

Head and neck squamous cell carcinomas (HNSCCs) are epithelial malignancies with 5-year overall survival rates of approximately 40-50%. Emerging evidence indicates that a small population of cells in HNSCC patients, named cancer stem cells (CSCs), play vital roles in the processes of tumor initiation, progression, metastasis, immune evasion, chemo-/radioresistance, and recurrence. The acquisition of stem-like properties of cancer cells further provides cellular plasticity for stress adaptation and contributes to therapeutic resistance, resulting in a worse clinical outcome. Thus, targeting cancer stemness is fundamental for cancer treatment. MicroRNAs (miRNAs) are known to regulate stem cell features in the development and tissue regeneration through a miRNA-target interactive network. In HNSCCs, miRNAs act as tumor suppressors and/or oncogenes to modulate cancer stemness and therapeutic efficacy by regulating the CSC-specific tumor microenvironment (TME) and signaling pathways, such as epithelial-to-mesenchymal transition (EMT), Wnt/ß-catenin signaling, and epidermal growth factor receptor (EGFR) or insulin-like growth factor 1 receptor (IGF1R) signaling pathways. Owing to a deeper understanding of disease-relevant miRNAs and advances in in vivo delivery systems, the administration of miRNA-based therapeutics is feasible and safe in humans, with encouraging efficacy results in early-phase clinical trials. In this review, we summarize the present findings to better understand the mechanical actions of miRNAs in maintaining CSCs and acquiring the stem-like features of cancer cells during HNSCC pathogenesis.

Muscle atrophy-related myotube-derived exosomal microRNA in neuronal dysfunction: Targeting both coding and long noncoding RNAs.

In mammals, microRNAs can be actively secreted from cells to blood. miR-29b-3p has been shown to play a pivotal role in muscle atrophy, but its role in intercellular communication is largely unknown. Here, we showed that miR-29b-3p was upregulated in normal and premature aging mouse muscle and plasma. miR-29b-3p was also upregulated in the blood of aging individuals, and circulating levels of miR-29b-3p were negatively correlated with relative appendicular skeletal muscle. Consistently, miR-29b-3p was observed in exosomes isolated from long-term differentiated atrophic C2C12 cells. When C2C12-derived miR-29b-3p-containing exosomes were uptaken by neuronal SH-SY5Y cells, increased miR-29b-3p levels in recipient cells were observed. Moreover, miR-29b-3p overexpression led to downregulation of neuronal-related genes and inhibition of neuronal differentiation. Interestingly, we identified HIF1α-AS2 as a novel c-FOS targeting lncRNA that is induced by miR-29b-3p through down-modulation of c-FOS and is required for miR-29b-3p-mediated neuronal differentiation inhibition. Our results suggest that atrophy-associated circulating miR-29b-3p may mediate distal communication between muscle cells and neurons.

Targeting non-muscle myosin II promotes corneal endothelial migration through regulating lamellipodial dynamics.

Corneal endothelial cell (CEC) dysfunction causes corneal edema that may lead to blindness. In addition to corneal transplantation, simple descemetorhexis has been proposed to treat centrally located disease with adequate peripheral cell reserve, but promoting the centripetal migration of CECs is pivotal to this strategy. Here, we show that targeting non-muscle myosin II (NMII) activity by Y27632, a ROCK inhibitor, or blebbistatin, a selective NMII inhibitor, promotes directional migration of CECs and accelerates in vitro wound healing. The lamellipodial protrusion persistence is increased, and actin retrograde flow is decreased after NMII inhibition. Counteracting lamellipodial protrusion by actin-related protein 2/3 (ARP2/3) inhibitor abolishes this migration-promoting effect. Although both Y27632 and blebbistatin accelerate wound healing, cell junctional integrity and barrier function are better preserved after blebbistatin treatment, leading to more rapid corneal deturgescence in rabbit corneal endothelial wounding model. Our findings indicate that NMII is a promising therapeutic target in the treatment of CEC dysfunction. KEY MESSAGES: NMII inhibition promotes directional migration and wound healing of CECs in vitro. Lamellipodial protrusion persistence is increased after NMII inhibition. Selective NMII inhibitor preserves junctional integrity better than ROCK inhibitor. Selective NMII inhibitor accelerates corneal deturgescence after wounding in vivo.

RAB27B-activated secretion of stem-like tumor exosomes delivers the biomarker microRNA-146a-5p, which promotes tumorigenesis and associates with an immunosuppressive tumor microenvironment in colorectal cancer.

The dynamic cell-cell communication is essential for tissue homeostasis in normal physiological circumstances and contributes to a diversified tumor microenvironment. Although exosomes are extracellular vesicles that actively participate in cell-cell interaction by shutting cellular components, impacts of tumor exosomes in the context of cancer stemness remain elusive. Here, we expand colorectal cancer stem cells (CRCSCs) as cancer spheroids and demonstrate that the ß-catenin/Tcf-4-activated RAB27B expression is required for the secretion of CRCSC exosomes. In an exosomal RNA sequencing analysis, a switch of exosomal RNA species from retrotransposons to microRNAs (miRNAs) is identified upon expanding CRCSCs. miRNA-146a-5p (miR-146a) is the major miRNA in CRCSC exosomes and exosomal miR-146a promotes stem-like properties and tumorigenicity by targeting Numb in recipient CRC cells. Among 53 CRC patients, those with abundant exosomal miR-146a expression in serum exhibits higher miR-146aHigh /NumbLow CRCSC traits, an increased number of tumor-filtrating CD66(+) neutrophils and a decreased number of tumor-infiltrating CD8(+) T cells. Our study elucidates a unique mechanism of tumor exosome-mediated stemness expansion.

Author Correction: MicroRNA-146a directs the symmetric division of Snail-dominant colorectal cancer stem cells.

In the version of Supplementary Fig. 6c originally published with this Article, the immunoprecipitation (IP) and immunoblotting (IB) tags in the top panel were mislabelled. In addition, in Supplementary Fig. 6e, the blot of the IP: Numb; IB: ß-Trcp panel for HCT15 was mistakenly duplicated for HCT116. The correct versions of these figures are shown below. An independent repeat of the experiments presented in Supplementary Fig. 6c and e, showing results that are consistent with those reported in the unprocessed blots, have been deposited in figshare ( 10.6084/m9.figshare.7570685 ).

Tumor stem-like cell-derived exosomal RNAs prime neutrophils for facilitating tumorigenesis of colon cancer.

BACKGROUND: Cell-cell interactions maintain tissue homeostasis and contribute to dynamic alteration of the tumor microenvironment (TME). Communication between cancer and host cells not only promotes advanced disease aggression but also determines therapeutic response in cancer patients. Despite accumulating evidence supporting the role of tumor-infiltrating immunocytes in modulating tumor immunity, the interplay between heterogeneous tumor subpopulations and immunocytes is elusive. METHODS: We expanded colorectal cancer stem cells (CRCSCs) as cancer spheroids from the murine colorectal cancer (CRC) cell line CT26 to interrogate tumor-host interactions using a syngeneic tumor model. RNA-sequencing analysis of host cells and tumor exosomes was performed to identify molecular determinants that mediate the crosstalk between CRCSCs and immunocytes. The Cancer Genome Atlas (TCGA) database was used to validate the clinical significance in CRC patients. RESULTS: The expanded CT26 cancer spheroids showed increased stemness gene expression, enhanced spheroid and clonogenicity potential, and an elevated tumor-initiating ability, characteristic of CRCSCs. By examining immune cell composition in syngeneic tumor-bearing mice, a systemic increase in CD11b+/Ly6GHigh/Ly6CLow neutrophils was observed in mice bearing CRCSC-derived tumors. An increased secretion of CRCSC exosomes was observed in vitro, and through in vivo tracking, CRCSC exosomes were found to be transported to the bone marrow. Moreover, CRCSC exosomes prolonged the survival of bone marrow-derived neutrophils and engendered a protumoral phenotype in neutrophils. Mechanistically, tumor exosomal tri-phosphate RNAs induced the expression of interleukin-1ß (IL-1ß) through a pattern recognition-NF-κB signaling axis to sustain neutrophil survival. CRCSC-secreted CXCL1 and CXCL2 then attracted CRCSC-primed neutrophils to promote tumorigenesis of CRC cells via IL-1ß. Moreover, neutrophil depletion using a Ly6G-specific antibody (clone 1A8) attenuated the tumorigenicity of CRCSCs. In human specimens, CRC patients exhibiting an active CRCSC signal (Snail+IL8+) showed elevated tumor infiltration of MPO+ neutrophils, and high (in the top 10%) MPO expression predicted poor survival of CRC patients. CONCLUSIONS: This study elucidates a multistep CRCSC-neutrophil interaction during advanced cancer progression. Strategies targeting aberrant neutrophil activation may be developed for combating CSC-related malignancy.

Macrophage-secreted interleukin-35 regulates cancer cell plasticity to facilitate metastatic colonization.

A favorable interplay between cancer cells and the tumor microenvironment (TME) facilitates the outgrowth of metastatic tumors. Because of the distinct initiating processes between primary and metastatic tumors, we investigate the differences in tumor-associated macrophages (TAMs) from primary and metastatic cancers. Here we show that dual expression of M1 and M2 markers is noted in TAMs from primary tumors, whereas predominant expression of M2 markers is shown in metastatic TAMs. At metastatic sites, TAMs secrete interleukin-35 (IL-35) to facilitate metastatic colonization through activation of JAK2-STAT6-GATA3 signaling to reverse epithelial-mesenchymal transition (EMT) in cancer cells. In primary tumors, inflammation-induced EMT upregulates IL12Rß2, a subunit of the IL-35 receptor, in cancer cells to help them respond to IL-35 during metastasis. Neutralization of IL-35 or knockout of IL-35 in macrophages reduces metastatic colonization. These results indicate the distinct TMEs of primary and metastatic tumors and provide potential targets for intercepting metastasis.

Risk analysis of malignant potential of oral verrucous hyperplasia: A follow-up study of 269 patients and copy number variation analysis.

BACKGROUND: Oral verrucous hyperplasia is commonly observed in the oral cavity of betel quid chewers and is a potential malignant disorder. However, the prognostic factors and genetic alterations of oral verrucous hyperplasia are unclear. METHODS: We calculate the survival rate and prognostic factors using a Kaplan-Meier analysis and Cox proportional hazards regression model. Copy number variations were analyzed using a single-nucleotide polymorphism (SNP) array. RESULTS: The 5-year disease-free and cancer-free survival rates of patients with oral verrucous hyperplasia were approximately 40% and 70%, respectively. Heavy betel quid chewing, advanced oral submucous fibrosis, and nonbuccal and nontongue lesions were risk factors for malignant transformation, whereas dysplasia did not affect outcomes. The gene amplification of CTTN, FOLR3, ORAOV1, PPFIA1, and RNF121 were associated with the poor prognosis of oral verrucous hyperplasia. CONCLUSION: Heavy betel quid chewing, advanced oral submucous fibrosis, and nonbuccal and nontongue lesions are high-risk factors of patients with oral verrucous hyperplasia. The 5-copy number variation-associated genes could be used for early diagnosis and predicting the prognosis.