Characterization of gastric cancer stem-like molecular features, immune and pharmacogenomic landscapes.

Cancer stem cells (CSCs) actively reprogram their tumor microenvironment (TME) to sustain a supportive niche, which may have a dramatic impact on prognosis and immunotherapy. However, our knowledge of the landscape of the gastric cancer stem-like cell (GCSC) microenvironment needs to be further improved. A multi-step process of machine learning approaches was performed to develop and validate the prognostic and predictive potential of the GCSC-related score (GCScore). The high GCScore subgroup was not only associated with stem cell characteristics, but also with a potential immune escape mechanism. Furthermore, we experimentally demonstrated the upregulated infiltration of CD206+ tumor-associated macrophages (TAMs) in the invasive margin region, which in turn maintained the stem cell properties of tumor cells. Finally, we proposed that the GCScore showed a robust capacity for prediction for immunotherapy, and investigated potential therapeutic targets and compounds for patients with a high GCScore. The results indicate that the proposed GCScore can be a promising predictor of prognosis and responses to immunotherapy, which provides new strategies for the precision treatment of GCSCs.

Exosome-transmitted miR-29a induces colorectal cancer metastasis by destroying the vascular endothelial barrier.

Metastasis is the leading cause of colorectal cancer treatment failure and mortality. Communication between endothelium and tumor cells in the tumor microenvironment is required for cancer metastasis. Tumor-derived exosomes have been shown to increase vascular permeability by delivering microRNA (miRNA) to vascular endothelial cells, facilitating cancer metastasis. The mechanism by which Epithelial-mesenchymal transition (EMT) tumor cell-derived exosomes influence vascular permeability remains unknown. MicroRNA-29a (miR-29a) expression is up-regulated in colorectal cancer (CRC) tissues, which is clinically significant in metastasis. Exosomal miR-29a secreted by EMT-CRC cells has been found to decrease the expression of Zonula occlusion 1 (ZO-1), Claudin-5, and Occludin via targeting Kruppel-like factor 4 (KLF4). In vitro co-culture investigations further revealed that EMT-cancer cells release exosomal miR-29a, which alters vascular endothelial permeability. Furthermore, exosomal miR-29a promoted liver metastases in CRC mice. Our findings demonstrate that EMT-CRC cells may transport exosomal miR-29a to endothelial cells in the tumor microenvironment (TME). As a result, increased vascular permeability promotes the development and metastasis of CRC. Exosomal miR-29a has the potential to be a predictive marker for tumor metastasis as well as a viable therapeutic target for CRC.

Tumor-derived exosomal microRNA-106b-5p activates EMT-cancer cell and M2-subtype TAM interaction to facilitate CRC metastasis.

Epithelial-mesenchymal transition (EMT) is reported to involve in the crosstalk between tumor cells and tumor-associated macrophages (TAMs). Exosomes are considered as important mediators of orchestrating intercellular communication. However, the underlying mechanisms by which EMT-colorectal cancer (CRC) cells promote the M2 polarization of TAMs remain less understood. In this study, we found that EMT-CRC cells promoted the M2-like polarization of macrophages by directly transferring exosomes to macrophages, leading to a significant increase of the microRNA-106b-5p (miR-106b) level in macrophages. Mechanically, an increased level of miR-106b activated the phosphatidylinositol 3-kinase (PI3K)γ/AKT/mammalian target of rapamycin (mTOR) signaling cascade by directly suppressing programmed cell death 4 (PDCD4) in a post-transcription level, contributing to the M2 polarization of macrophages. Activated M2 macrophages, in a positive-feedback manner, promote EMT-mediated migration, invasion, and metastasis of CRC cells. Clinically, miR-106b was significantly elevated in CRC tissues and negatively correlated with the levels of PDCD4 in CRC specimens, and high expression of exosomal miR-106b in plasma was significantly associated with the malignant progression of CRC. Taken together, our results indicate that exosomal miR-106b derived from EMT-CRC cells has an important role in intercellular communication for inducing M2 macrophage polarization, illuminating a novel mechanism underlying CRC progression and offering potential targets for prevention of CRC metastasis.

M2 macrophage-derived G-CSF promotes trophoblasts EMT, invasion and migration via activating PI3K/Akt/Erk1/2 pathway to mediate normal pregnancy.

Trophoblasts are important parts of the placenta and exert vital roles in the maternal-foetal crosstalk, and sufficient trophoblasts migration and invasion is critical for embryo implantation and normal pregnancy. Macrophages, as the major components of decidual microenvironment at maternal-foetal interface, can interact with trophoblasts to participate in the regulation of normal pregnancy. Previously, our group have demonstrated that trophoblasts could induce macrophages polarization to M2 subtype by secreting interleukin-6 (IL-6); however, the understanding of macrophages regulating the migration and invasion of trophoblasts is limited. In the present study, we used the co-cultured model to further investigate the effects of macrophages on trophoblasts migration and invasion. Our results showed that co-culture with macrophages promoted epithelial-to-mesenchymal transition (EMT) of trophoblasts, thereby enhancing their migrative and invasive abilities. Further experiments revealed that M2 macrophage-derived G-CSF was a key factor, which promoted the EMT, migration and invasion of trophoblasts via activating PI3K/Akt/Erk1/2 signalling pathway. Clinically, G-CSF was highly expressed in placental villous tissues of normal pregnancy patients compared to patients with recurrent spontaneous abortion, and its expression level was significantly correlation with EMT markers. Taken together, these findings indicate the important role of M2 macrophages in regulating trophoblasts EMT, migration and invasion, contributing to a new insight in concerning the crosstalk between macrophages and trophoblasts in the establishment and maintenance of normal pregnancy.

Tumour microenvironment: a non-negligible driver for epithelial-mesenchymal transition in colorectal cancer.

Cancer remains the leading cause of death worldwide, and metastasis is still the major cause of treatment failure for cancer patients. Epithelial-mesenchymal transition (EMT) has been shown to play a critical role in the metastasis cascade of epithelium-derived carcinoma. Tumour microenvironment (TME) refers to the local tissue environment in which tumour cells produce and live, including not only tumour cells themselves, but also fibroblasts, immune and inflammatory cells, glial cells and other cells around them, as well as intercellular stroma, micro vessels and infiltrated biomolecules from the nearby areas, which has been proved to widely participate in the occurrence and progress of cancer. Emerging and accumulating studies indicate that, on one hand, mesenchymal cells in TME can establish 'crosstalk' with tumour cells to regulate their EMT programme; on the other, EMT-tumour cells can create a favourable environment for their own growth via educating stromal cells. Recently, our group has conducted a series of studies on the interaction between tumour-associated macrophages (TAMs) and colorectal cancer (CRC) cells in TME, confirming that the interaction between TAMs and CRC cells mediated by cytokines or exosomes can jointly promote the metastasis of CRC by regulating the EMT process of tumour cells and the M2-type polarisation process of TAMs. Herein, we present an overview to describe the current knowledge about EMT in cancer, summarise the important role of TME in EMT, and provide an update on the mechanisms of TME-induced EMT in CRC, aiming to provide new ideas for understanding and resisting tumour metastasis.

Wnt5a-induced M2 polarization of tumor-associated macrophages via IL-10 promotes colorectal cancer progression.

BACKGROUND: Tumor-associated macrophages (TAMs) in the tumor microenvironment influence tumor initiation, invasion and metastasis. Several studies have shown that Wnt5a is mainly expressed in the tumor stroma, especially in TAMs. However, whether Wnt5a regulates the polarization and biological function of TAMs in colorectal cancer (CRC) is incompletely understood. METHODS: Immunofluorescence staining was performed to detect CD68 and Wnt5a expression in colorectal tissues from patients (63 CRC specimens VS 20 normal tissues). RT-qPCR, flow cytometry, ELISA and inhibitors were carried out to explore the role of Wnt5a in the polarization of TAMs. Clone formation and transwell assays were performed to determine the effects of Wnt5a-treated macrophages on tumor proliferation, migration and invasion in vitro. Finally, a xenograft model was applied to confirm the effects of Wnt5a+ TAMs on CRC tumorigenesis. RESULTS: We found that high Wnt5a+CD68+/CD68+ TAMs ratio was significantly associated with poor prognosis in CRC patients and Wnt5a+ TAM was an M2-like TAM subtype. Subsequently, we found that Wnt5a induced macrophages to secrete IL-10, which then acted as an autocrine cytokine to induce M2 polarization of these macrophages. IL-10 neutralizing antibody completely reversed the pro-M2 effect of Wnt5a. Mechanistically, the CaKMII-ERK1/2-STAT3 pathway was required for Wnt5a-mediated IL-10 expression in macrophages. Furthermore, Wnt5a-induced M2 macrophages promoted CRC cells proliferation, migration and invasion; knockdown of Wnt5a in TAMs significantly impaired the pro-tumor functions of TAMs. CONCLUSIONS: Our data indicate that Wnt5a could induce M2 polarization of TAMs by regulating CaKMII-ERK1/2-STAT3 pathway-mediated IL-10 secretion, ultimately promoting tumor growth and metastasis of CRC.

Crosstalk between cancer cells and tumor associated macrophages is required for mesenchymal circulating tumor cell-mediated colorectal cancer metastasis.

BACKGROUND: Tumor-associated macrophages (TAMs) are major components of tumor microenvironment that frequently associated with tumor metastasis in human cancers. Circulating tumor cell (CTC), originating from primary tumor sites, is considered to be the precursors of tumor metastasis. However, the regulatory mechanism of TAMs in CTC-mediated tumor metastasis still remains unclear. METHODS: Immunohistochemical staining was used to detect the macrophages infiltration (CD68 and CD163), epithelial-mesenchymal transition (EMT) markers (E-cadherin and Vimentin) expression in serial sections of human colorectal cancer (CRC) specimens. Then, the correlations between macrophages infiltration and clinicopathologic features, mesenchymal CTC ratio, and patients' prognosis were analyzed. A co-culture assay in vitro was used to evaluate the role of TAMs on CRC EMT, migration and invasion, and ELISA, luciferase reporter assay and CHIP were performed to uncover the underlying mechanism. Furthermore, an in vivo model was carried out to confirm the effect of TAMs on mesenchymal CTC-mediated metastasis. RESULTS: Clinically, CD163+ TAMs infiltrated in invasive front was associated with EMT, mesenchymal CTC ratio, and poor prognosis in patients with CRC. CRC-conditioned macrophages regulated EMT program to enhance CRC cells migration and invasion by secreting IL6. TAMs-derived IL6 activated the JAK2/STAT3 pathway, and activated STAT3 transcriptionally inhibited the tumor suppressor miR-506-3p in CRC cells. miR-506-3p, a key miRNA regulating FoxQ1, was downregulated in CRC cells, resulting in increased FoxQ1 expression, which in turn led to the production of CCL2 that promoted macrophage recruitment. Inhibition of CCL2 or IL6 broke this loop and reduced macrophage migration and mesenchymal CTC-mediated metastasis, respectively. CONCLUSIONS: Our data indicates that TAMs induce EMT program to enhance CRC migration, invasion, and CTC-mediated metastasis by regulating the JAK2/STAT3/miR-506-3p/FoxQ1 axis, which in turn leads to the production of CCL2 that promote macrophage recruitment, revealing a new cross-talk between immune cells and tumor cells in CRC microenvironment.

Wedge-shaped microfluidic chip for circulating tumor cells isolation and its clinical significance in gastric cancer.

BACKGROUND: Circulating tumor cells (CTCs) have great potential in both basic research and clinical application for the managements of cancer. However, the complicated fabrication processes and expensive materials of the existing CTCs isolation devices, to a large extent, limit their clinical translation and CTCs' clinical value. Therefore, it remains to be urgently needed to develop a new platform for achieving CTCs detection with low-cost, mass-producible but high performance. METHODS: In the present study, we introduced a novel wedge-shaped microfluidic chip (named CTC-ΔChip) fabricated by two pieces of glass through wet etching and thermal bonding technique for CTCs isolation, which achieved CTCs enrichment by different size without cell surface expression markers and CTCs identification with three-color immunocytochemistry method (CK+/CD45-/Nucleus+). We validated the feasibility of CTC-ΔChip for detecting CTCs from different types of solid tumor. Furthermore, we applied the newly-developed platform to investigate the clinical significance of CTCs in gastric cancer (GC). RESULTS: Based on "label-free" characteristic, the capture efficiency of CTC-ΔChip can be as high as 93.7 ± 3.2% in DMEM and 91.0 ± 3.0% in whole blood sample under optimized conditions. Clinically, CTC-ΔChip exhibited the feasibility of detecting CTCs from different types of solid tumor, and it identified 7.30 ± 7.29 CTCs from 2 mL peripheral blood with a positive rate of 75% (30/40) in GC patients. Interestingly, we found that GC CTCs count was significantly correlated with multiple systemic inflammation indexes, including the lymphocyte count, platelet count, the level of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio. In addition, we also found that both the positivity rate and CTCs count were significantly associated with multiple clinicopathology parameters. CONCLUSIONS: Our novel CTC-ΔChip shows high performance for detecting CTCs from less volume of blood samples of cancer patients and important clinical significance in GC. Owing to the advantages of low-cost and mass-producible, CTC-ΔChip holds great potential of clinical application for cancer therapeutic guidance and prognostic monitoring in the future.

A simple pyramid-shaped microchamber towards highly efficient isolation of circulating tumor cells from breast cancer patients.

Isolation and detection of circulating tumor cells (CTCs) has showed a great clinical impact for tumor diagnosis and treatment monitoring. Despite significant progresses of the existing technologies, feasible and cost-effective CTC isolation techniques are more desirable. In this study, a novel method was developed for highly efficient isolation of CTCs from breast cancer patients based on biophysical properties using a pyramid-shaped microchamber. Through optimization tests, the outlet height of 6 µm and the flow rate of 200 µL/min were chosen as the optimal conditions. The capture efficiencies of more than 85% were achieved for cancer cell lines (SKBR3, BGC823, PC3, and H1975) spiked in DMEM and healthy blood samples without clogging issue. In clinic assay, the platform identified CTCs in 13 of 20 breast cancer patients (65%) with an average of 4.25 ± 4.96 CTCs/2 mL, whereas only one cell was recognized as CTC in 1 of 15 healthy blood samples. The statistical analyses results demonstrated that both CTC positive rate and CTC counts were positive correlated with TNM stage (p < 0.001; p = 0.02, respectively). This microfluidic platform successfully demonstrated the clinical feasibility of CTC isolation and would hold great potential of clinical application in predicting and monitoring the prognosis of cancer patients.

Prognostic and clinicopathological significance of circulating tumor cells detected by RT-PCR in non-metastatic colorectal cancer: a meta-analysis and systematic review.

BACKGROUND: Circulating tumor cells (CTCs) have been accepted as a prognostic marker in patients with metastatic colorectal cancer (mCRC, UICC stage IV). However, the prognostic value of CTCs in patients with non-metastatic colorectal cancer (non-mCRC, UICC stage I-III) still remains in dispute. A meta-analysis was performed to investigate the prognostic significance of CTCs detected by the RT-PCR method in patients diagnosed with non-mCRC patients. METHODS: A comprehensive literature search for relevant articles was performed in the EmBase, PubMed, Ovid, Web of Science, Cochrane library and Google Scholar databases. The studies were selected according to predetermined inclusion/exclusion criteria. Using the random-effects model of Stata software, version12.0 (2011) (Stata Corp, College Station, TX, USA), to conduct the meta-analysis, and the hazard ratio (HR), risk ratio (RR) and their 95% confidence intervals (95% CIs) were regarded as the effect measures. Subgroup analyses and meta-regression were also conducted to clarify the heterogeneity. RESULTS: Twelve eligible studies, containing 2363 patients with non-mCRC, were suitable for final analyses. The results showed that the overall survival (OS) (HR = 3.07, 95% CI: [2.05-4.624], P < 0.001; I2 = 55.7%, P = 0.008) and disease-free survival (DFS) (HR = 2.58, 95% CI: [2.00-3.32], P < 0.001; I2 = 34.0%, P = 0.085) were poorer in patients with CTC-positive, regardless of the sampling time, adjuvant therapy and TNM stage. CTC-positive was also significantly associated with regional lymph nodes (RLNs) metastasis (RR = 1.62, 95% CI: [1.17-2.23], P = 0.003; I2 = 74.6%, P<0.001), depth of infiltration (RR = 1.41, 95% CI: [1.03-1.92], P = 0.03; I2 = 38.3%, P = 0.136), vascular invasion (RR = 1.66, 95% CI: [1.17-2.36], P = 0.004; I2 = 46.0%, P = 0.135), tumor grade (RR = 1.19, 95% CI: [1.02-1.40], P = 0.029; I2 = 0%, P = 0.821) and tumor-node-metastasis (TNM) stage(I, II versus III) (RR = 0.76, 95% CI 0.71-0.81, P < 0.001; I2 = 0%, P = 0.717). However, there was no significant relationship between CTC-positive and tumor size (RR = 1.08, 95% CI: [0.94-1.24], P = 0.30; I2 = 0%, P = 0.528). CONCLUSIONS: Detection of CTCs by RT-PCR method has prognostic value for non-mCRC patients, and CTC-positive was associated with poor prognosis and poor clinicopathological prognostic factors. However, the prognostic value of CTCs supports the use of CTCs as an indicator of metastatic disease prior to the current classification of mCRC meaning it is detectable by CT/MRI.

Efficacy and safety of target combined chemotherapy in advanced gastric cancer: a meta-analysis and system review.

BACKGROUND: The aim of our meta-analysis is to assess the efficacy and safety of the target combined chemotherapy for the patients with unresectable advanced or recurrent gastric cancer. METHODS: In accordance with the standard meta-analysis procedures, the patients included in our study were with unresectable advanced or recurrent gastric cancer and allocated randomly to receive target combined chemotherapy or the traditional chemotherapy. The search was applied to PubMed, EMBASE, Science Citation Index Expanded, Cocran's library (from inception to February 2016). All analyses were performed by STATA 12.0, with the odds ratio, hazard ratio, and 95 % confidence interval as the effect measures. RESULTS: Fourteen studies were included in this meta-analysis. A total of 5067 patients with advanced gastric cancer were divided into two arms: traditional chemotherapy arm and target combined chemotherapy arm. A significant improvement for overall survival (hazard ratio was 0.89, 95 % confidence interval: 0.83-0.95) and overall response rate (odds ratio was 1.44, 95 % confidence interval: 1.15-1.81) was observed, but no significant difference was found for progression-free survival (hazard ratio was 0.89, 95 % confidence interval: 0.77-1.00) in the target combined chemotherapy arm. In subgroup analysis, increasing benefits regarding overall survival and progression-free survival were found in anti epidermal growth factor receptor target drugs for selected patients subgroup and anti vascular endothelial growth factor receptor target drugs for unselected patients subgroup, but not in anti epidermal growth factor receptor target drugs for unselected patients subgroup. Besides, some adverse events were increased in the target combined chemotherapy arm. CONCLUSIONS: The target combined chemotherapy represented a better overall survival benefit and treatment efficiency and higher incidence of some grade 3-4 adverse events than the traditional chemotherapy for patients with unresectable advanced or recurrence gastric cancer. The anti vascular endothelial growth factor receptor drugs can improve the efficacy in the whole patients with unresectable advanced or recurrence gastric cancer and the anti epidermal growth factor receptor target drugs can only improve the efficacy in the epidermal growth factor receptor positive patients.

RPN2 in cancer: An overview.

Oncogenes together with tumor suppresser genes are confirmed to regulate tumor phenotype in human cancers. RPN2, widely verified as an oncogene, encodes a protein that is part of an N-oligosaccharyl transferase, and is observed to be aberrantly expressed in human malignancies. Accumulating evidence unveils the vital functions of RPN2, contributing to tumorigenicity, metastasis, progression, and multi-drug resistance. Furthermore, previous studies partly indicated that RPN2 was involved in tumor progression via contributing to N-glycosylation and regulating multiple signaling pathways. In addition, RPN2 was also confirmed as a downstream target involved in tumor progression. Moreover, with demonstrated prognosis value and therapeutic target, RPN2 was also determined as a promising biomarker for forecasting patients' prognostic and therapy efficacy. In the present review, we aimed to summarize the present studies of RPN2 in cancer, and enhance the understanding of RPN2's extensive functions and clinical significances.

PFDN2 promotes cell cycle progression via the hnRNPD-MYBL2 axis in gastric cancer.

Gastric cancer (GC) is a major health burden worldwide, but our understanding of GC is limited, and the prognosis is poor. Novel therapeutic strategies and biomarkers are urgently needed to improve GC patient outcomes. Previously, we identified PFDN2 as a novel key gene in gastric cancer based on its differential expression between cancer and normal tissues. However, the role and underlying mechanisms of PFDN2 in GC remain elusive. In this article, we demonstrated that PFDN2 is highly expressed in GC and that upregulation of PFDN2 is associated with the progression of GC. We further found that PFDN2 could promote cell cycle progression by promoting MYBL2 expression. Mechanistically, we demonstrated that PFDN2 could upregulate MYBL2 expression by facilitating the nuclear translocation of hnRNPD, and thus promoting MYBL2 transcriptional program. In conclusion, we found that PFDN2 promotes cell cycle progression via the hnRNPD-MYBL2 axis and may serve as a potential biomarker and therapeutic target for GC.

BGN/FAP/STAT3 positive feedback loop mediated mutual interaction between tumor cells and mesothelial cells contributes to peritoneal metastasis of gastric cancer.

Peritoneal metastasis (PM) is most frequent in gastric cancer (GC) and cancer-associated fibroblasts (CAFs) play a critical role in this process. However, the concrete mechanism of crosstalk between CAFs and cancer cells in PM of GC remains unclear. Microarray sequencing of GC focus and PM lesions was performed, and biglycan (BGN) was screened for further study. Clinically, BGN expression was higher in GC tissues than adjacent normal tissues, and high expression correlated with poor prognosis. In vitro experiments demonstrated that BGN promoted tumor progression and the transformation of mesothelial cells (MCs) into cancer-associated fibroblasts like cells (CAFLCs). In turn, CAFLCs-derived fibroblast activation protein (FAP) facilitated the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of GC cells. GC-derived BGN combined with toll like receptor 2 (TLR2)/TLR4 on MCs to activate the NF-κB pathway and promote the transformation of MCs into CAFLCs by the recovery experiment, coimmunoprecipitation assay, nuclear and cytoplasmic protein extraction assay. CAFLCs-derived FAP could activate the JAK2/STAT3 signaling pathway in GC. Finally, activated STAT3 promoted BGN transcription in GC, resulting in a BGN/FAP-STAT3 positive feedback loop. Taken together, mutual interaction between tumor cells and activated MCs mediated by a BGN/FAP-STAT3 positive feedback loop facilitates PM of GC and provides a potential biomarker and therapeutic target for GC metastasis.

Upregulation of LINC00501 by H3K27 acetylation facilitates gastric cancer metastasis through activating epithelial-mesenchymal transition and angiogenesis.

BACKGROUND: The molecular mechanism of the significant role of long noncoding RNAs (lncRNAs) in the progression and metastasis of gastric cancer (GC) remains largely elusive. Our objective is to detect overexpressed lncRNA in GC and investigate its role in promoting epithelial-mesenchymal transition and tumour microenvironment remodel. METHODS: LncRNA differential expression profile in GC was analysed using RNA microarrays. The level of LINC00501 was evaluated in both GC patient tissues and GC cell lines by quantitative reverse transcription PCR and large-scale (n = 304) tissue microarray. To explore the biological role and regulatory driver of LINC00501 in GC, various experimental techniques including Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP) assay, dual luciferase assays were performed. RESULTS: Clinically, it was observed that LINC00501 level was abnormal overexpression in GC tissue and was associated with GC progression and distant metastasis. Gain and loss molecular biological experiments suggested that LINC00501, promoted EMT process and angiogenesis of GC. Mechanically, the enrichment of H3K27 acetylation in LINC00501 promoter region contributed to the increase of LINC00501 in GC. LINC00501 transactivated transcription of SLUG, by recruiting hnRNPR to its promoter. The growth of GC was inhibited both in vitro and in vivo by suppressing the level of LINC00501 using pharmacological intervention from the histone acetyltransferase (HAT) inhibitor -C646. CONCLUSIONS: This study suggests that LINC00501 promotes GC progression via hnRNPR/SLUG pathway, which indicates a promising biomarker and target for GC.

Granulocyte colony-stimulating factor in reproductive-related disease: Function, regulation and therapeutic effect.

Granulocyte colony-stimulating factor (G-CSF) is one of the cytokines which plays important roles in embryo implantation and normal pregnancy. At the maternal-fetal interface, G-CSF can be synthesized by multiple cells, and participates in regulation of trophoblast development, endometrial decidualization, placental metabolism and angiogenesis. Moreover, as an important medium of intercellular communication, G-CSF has also been shown to exert key roles in crosstalk between cellular components at the maternal-fetal interface. Recently, our study demonstrated that G-CSF derived from M2 macrophage could promote trophoblasts invasion and migration through activating PI3K/AKT/Erk1/2 pathway, thereby involving in normal pregnancy program. Herein, we will summarize the role and regulation of G-CSF in normal pregnancy and reproductive-related disease, and the clinical applications of G-CSF in patients undergoing in vitro fertilization with thin endometrium, repeated implantation failure, and women suffered with recurrent spontaneous abortion.

The lncRNA SEMA3B-AS1/HMGB1/FBXW7 Axis Mediates the Peritoneal Metastasis of Gastric Cancer by Regulating BGN Protein Ubiquitination.

Peritoneal metastasis (PM) is one of the main causes of a poor prognosis in patients with advanced gastric cancer (GC). lncRNAs have been confirmed to play a very crucial role in the occurrence, development, and metastasis of many human cancers, including gastric cancer. However, the mechanism of lncRNA in PM of GC is rarely studied. We explored the mechanism of PM of GC through lncRNA gene sequencing and protein profiling analysis to detect PM-associated lncRNAs and proteins. A quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to identify the mRNA expression of SEMA3B-AS1 and BGN in GC tissues and adjacent normal tissues. The biological function of SEMA3B-AS1 in the PM of GC was identified through gain- and loss-of-function assays. Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP), RNA pull-down, luciferase reporter, and coimmunoprecipitation (co-IP) assays was carried out to demonstrate the potential mechanism between SEMA3B-AS1 and its downstream genes, including HMGB1, FBXW7, and BGN. Finally, the biological function of SEMA3B-AS1 was demonstrated in animal experiments. The mRNA expression level of SEMA3B-AS1 was downregulated in GC and PM tissues compared to normal stomach tissues; however, BGN was highly expressed at the mRNA level. SEMA3B-AS1 was closely related to PM and the overall survival (OS) of GC patients. Functionally, the overexpression of SEMA3B-AS1 was related to GC progression, PM, and prognosis. Mechanistically, SEMA3B-AS1 could combine with HMGB1 to regulate the transcription of FBXW7, thus facilitating the ubiquitination of BGN. In conclusion, our study demonstrated that the SEMA3B-AS1/HMGB1/FBXW7 axis plays an inhibitory role in the PM of GC by regulating BGN protein ubiquitination. It also provides a new biological marker for the diagnosis and treatment of the PM of GC.

SNHG16 upregulation-induced positive feedback loop with YAP1/TEAD1 complex in Colorectal Cancer cell lines facilitates liver metastasis of colorectal cancer by modulating CTCs epithelial-mesenchymal transition.

Circulating tumor cells (CTCs) are important precursors of colorectal cancer (CRC) metastasis. The epithelial-mesenchymal transition (EMT) process facilitates CTC invasion by allowing these cells to evade antimetastatic checkpoints to mediate distant metastasis. However, the specific molecular mechanism of tumor EMT remains largely unknown. Based on our previous research on the YAP1 pathway, we further studied the upstream molecule small nucleolar RNA host gene 16 (SNHG16), whose expression was correlated with advanced TNM stage, distant metastasis, and poor prognosis in CRC patients. Furthermore, loss- and gain-of-function assays revealed that SNHG16 promoted CRC colony formation, proliferation, migration, invasion, EMT, mesenchymal-like CTC generation, and liver metastasis through YAP1. Mechanistically, SNHG16 acted as a miRNA sponge to sequester miR-195-5p on Ago2, thereby protecting YAP1 from repression. Moreover, YAP1 bound TEA domain transcription factor 1 (TEAD1) to form a YAP1/TEAD1 complex, which in turn bound two sites in the promoter of SNHG16 and regulate SNHG16 transcription. Finally, in vivo experiments showed that the inhibition of SNHG16 suppressed tumor progression, and that YAP1 rescued the effect of SNHG16 on tumor progression. Herein, we have clarified a hitherto unexplored SNHG16-YAP1/TEAD1 positive feedback loop, that may be a candidate target for CRC treatment.

LAMC1-mediated preadipocytes differentiation promoted peritoneum pre-metastatic niche formation and gastric cancer metastasis.

Gastric cancer is anatomically proximal to peritoneum. Gastric cancer peritoneal metastasis is a complex biological process which is corresponded with disharmony within dysfunctional adipose tissue and metabolism reprogramming. Laminin gamma 1 (LAMC1) is highly expressed in cancer cells of peritoneal metastatic sites, however, the mechanism of LAMC1-metiated gastric cancer metastases to adipose tissue-rich peritoneum remains unclear. In our study, immunohistochemical staining, single cell sequencing, a co-culture model, luciferase reporter, RNA immunoprecipitation (RIP), Chromatin immunoprecipitation (CHIP) and single-molecular magnetic tweezers assays were conducted, and our results showed that LAMC1 related to Perilipin-1 content was highly expressed in peritoneal metastatic sites and mainly secreted by tumor cells. Gastric cancer cells secreted LAMC1 in an autocrine manner to detached from the primary site and promoted preadipocytes mature, rupture and release of free fatty acids (FFAs) in the peritoneal microenvironment to form pre-metastatic niche by the paracrine pathway. Reversely, differentiated preadipocyte-derived conditioned medium inhibited glycolysis and enhanced fatty acid oxidation (FAO) rate to promote cell proliferation, mesenchymal-epithelial transformation which led to tumor peritoneal colonization. In terms of biological mechanisms, one of differentiated preadipocyte-derived FFAs, palmitic acid-activated STAT3 inhibited miR-193a-3p by binding to its promoter directly; Using single-molecular magnetic tweezers, this binding manner was proved to be stable, reversable and ATP-dependent. Moreover, miR-193a-3p regulated LAMC1 in a post-translational manner. Furthermore, high LAMC1 expression in serum predicted a higher risk of peritoneal metastasis. In conclusion, our results illustrated that palmitic acid/p-STAT3/miR-193a-3p/LAMC1 pathway promotes preadipocyte differentiation, pre-metastatic niche formation and gastric cancer cell colonization to peritoneum.

The lncRNA BDNF-AS/WDR5/FBXW7 axis mediates ferroptosis in gastric cancer peritoneal metastasis by regulating VDAC3 ubiquitination.

Ferroptosis is a novel form of cell death that is closely associated with the formation of many tumors. Our study focused on the mechanism by which long noncoding RNAs (lncRNAs) regulate ferroptosis in gastric cancer (GC) peritoneal metastasis (PM). We utilized lncRNA sequencing and protein profiling analysis to identify ferroptosis-associated lncRNAs and proteins. qRT-PCR was used to analyze the expression of BDNF-AS and FBXW7 in GC tissues and adjacent normal tissues. Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP), and coimmunoprecipitation (co-IP) assays were performed to investigate the interaction between BDNF-AS and its downstream targets. Finally, the function of BDNF-AS was validated in vivo . We demonstrated that BDNF-AS was highly expressed in GC and PM tissues. High BDNF-AS expression was positively related to GC progression and poor prognosis. Functionally, BDNF-AS overexpression protected GC cells from ferroptosis and promoted the progression of GC and PM. Mechanistically, BDNF-AS could regulate FBXW7 expression by recruiting WDR5, thus affecting FBXW7 transcription, and FBXW7 regulated the protein expression of VDAC3 through ubiquitination. Conclusively, our research demonstrated that the BDNF-AS/WDR5/FBXW7 axis regulates ferroptosis in GC by affecting VDAC3 ubiquitination. BDNF-AS might be a biomarker for the evaluation of GC prognosis and the treatment of GC.