Metastasis Of Colon Cancer Cells Research Articles

Abstract 3643: HDAC6 modulates colon cancer cell migration and invasion

Abstract Introduction: Non-histone protein acetylation in cancer cell regulates diverse biological functions that have been associated with tumorigenesis and cancer progression. HDAC6 is a tubulin-specific deacetylase which regulates microtubule-dependent cell movement. Here we investigated the role of HDAC6 on colon cancer progression. Methods: Colon tumor tissues were analyzed by immunohistochemistry to measure the expression of HDAC6. Attenuation of HDAC6 function was achieved using either inhibitors (Tubastatin and ACY-738) or siRNAs. Cell migration and invasion were determined using transwell assays. CCK8 and flow cytometry were used to assess the cell proliferation and cell survival respectively. We performed quantitative proteomic analyses to monitor changes in the abundance of protein lysine acetylation in response to HDAC6 deficiency. Immunoprecipitation assay was used to determine protein acetylation level and protein-protein interaction. Results: We identified that HDAC6 was highly expressed in metastatic colon cancer than non-metastatic colon cancer, indicating that HDAC6 is related with tumor metastasis. Selective suppression of HDAC6 or knocking down of HDAC6 significantly decreased colon cancer cell migration and invasion ability in vitro, without affecting cell proliferation and cell survival. In order to further clarify the role of HDAC6 in cell motility, we employed mass spectrometry-based label-free quantitative proteomics using human colon cancer cell line. We identified 42 proteins with > 2-fold increase of the acetylation level in the absence of HDAC6. These proteins are significantly enriched in processes related to cell-cell adhesion, cell division and several signaling pathways including cAMP and FoxO signaling pathway. We selected ENAH, an actin associated protein, as a potential new substrate of HDAC6, which has been previously reported to play important roles in cytoskeleton remodeling and cell polarity establishment. Immunoprecipitation analysis showed that HDAC6 can associate with ENAH under physical conditions. Besides, ENAH showed elevated acetylation in response to HDAC6 deletion. Conclusions: Our findings showed that inhibition of HDAC6 decreased the colon cancer cell migration and metastasis probably through regulating the acetylation level of ENAH. Our study also provided a resource of putative cytoplasmic targets of this deacetylase for further investigation. Considering that small molecule compounds targeting HDACs are currently undergoing clinical trials for the treatment of cancer, a better understanding of HDAC6-dependent cellular processes would be highly valuable for the evaluation of the clinical relevance and therapeutic efficacy of HDAC6 inhibitors. Citation Format: Hui Li. HDAC6 modulates colon cancer cell migration and invasion [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3643.

Curcumin inhibits CT26 cells metastasis by decreasing heparanase expression.

This study tested the hypothesis that heparanase (HPSE) is related to tumor metastasis and curcumin (CCM) inhibits tumor metastasis by down-regulating HPSE expression. MTT, Transwell assays, and RT-PCR were used to study the effects of CCM on the migration and invasion of CT26 cells and the expression of HPSE. CT26 cells were transfected with lentivirus to establish HPSE-overexpressing cells (OE) and corresponding negative control cells (NC). Signal pathways involved in down-regulating the expression of HPSE and inhibiting the migration and invasion of CT26 cells by CCM were screened by the liquid crystal chip. HPSE promoted CT26 cells migration and invasion, and CCM inhibited the proliferation and metastasis of CT26 cells. The results of RT-PCR indicated that CCM down-regulated HPSE expression. Liquid phase microarray showed that CCM inhibited the phosphorylation of P38 and STAT5 in CT26 cells and NC cells. In contrast, the inhibitory function of CCM was markedly enhanced when HPSE was overexpressed (P<0.05). In short, HPSE is closely related to metastasis of colon cancer cells. CCM inhibits colon cancer cell migration and invasion by inhibiting HPSE expression, which may be related to P38 MAPK and JAK/STAT5 signal pathways.

SRF Potentiates Colon Cancer Metastasis and Progression in a microRNA-214/PTK6-Dependent Manner.

ObjectiveSerum response factor (SRF), a sequence-specific transcription factor, is closely related to metastasis of gastric cancer, a digestive tract cancer. Herein, we probed the effect of SRF on metastasis and progression of colon cancer (CC), another digestive tract disorder, and the detailed mechanism.MethodsMicroarray analysis was conducted on tumor and adjacent tissues to filter differentially expressed miRNA, followed by RT-qPCR validation in CC cell lines. The transcription factor and the target gene of microRNA-214 (miR-214) were predicted, and their binding relationships were tested by luciferase reporter assays and ChIP assays. Subsequently, SRF and protein tyrosine kinase 6 (PTK6) expression in CC patients and cells was evaluated by RT-qPCR, while JAK2 and STAT3 expression in cells by Western blot analysis. To further explore functions of miR-214, PTK6 and SRF on CC, CC cells were delivered with si-PTK6, miR-214 mimic and/or SRF overexpression.ResultsmiR-214 expressed poorly in CC tissues and cell lines, which related to advanced TNM staging and survival. miR-214 mimic inhibited proliferation, migration, invasion, xenograft tumor growth and metastasis of CC cells. SRF, overexpressed in CC samples and cells, suppressed the transcription of miR-214. Meanwhile, SRF upregulation counteracted the inhibitory role of miR-214 mimic in CC cell growth. miR-214 negatively regulated PTK6 expression to impair the JAK2/STAT3 pathway activation, thereby halting CC cell proliferation, migration, invasion, xenograft tumor growth and metastasis.ConclusionAltogether, miR-214 may perform as a tumor suppressor in CC, and the SRF/miR-214/PTK6/JAK2/STAT3 axis could be applied as a biomarker and potential therapeutic target.

Rotenone restrains colon cancer cell viability, motility and epithelial‑mesenchymal transition and tumorigenesis in nude mice via the PI3K/AKT pathway.

Rotenone, a natural hydrophobic pesticide, has been reported to display anticancer activity in a variety of cancer cells. However, the mechanism of rotenone on colon cancer (CC) cell migration, invasion and metastasis is still unknown. In the present study, the cytotoxicity of rotenone on CC cells were detected by the Cell Counting Kit-8 assay and confirmed by clone formation assay. The effects of rotenone on CC cell invasion and migration activity were determined in vitro by Transwell invasion and wound healing assays, respectively. In addition, to reveal whether rotenone affected the epithelial-mesenchymal-transition (EMT) process, reverse transcription-quantitative PCR, western blotting and immunofluorescence assays were used to detect the expression of EMT markers. The expression levels of the key markers of the PI3K/AKT pathway after rotenone treatment alone or in combination with a PI3K/AKT signaling activator in CC were also detected by western blotting. Finally, the in vivo anti-tumor effects of rotenone were evaluated in a subcutaneous xenotransplant tumor model treated with an intraperitoneal injection of rotenone. The results of the present study demonstrated that rotenone treatment induced CC cell cytotoxicity and greater effects were observed with increasing concentrations and inhibited cell proliferation compared with untreated cells. In vitro cell function assays revealed that rotenone inhibited CC cell migration, invasion and EMT compared with untreated cells. Mechanically, the phosphorylation levels of AKT and mTOR were downregulated in rotenone-treated CC cells compared with untreated cells. Additionally, AKT and mTOR phosphorylation levels were increased by the PI3K/AKT signaling activator insulin-like growth factor 1 (IGF-1), which was reversed by rotenone treatment. The cell function assays confirmed that the IGF-1-activated cell proliferation, migration and invasion were decreased by rotenone treatment. These results indicated that rotenone affected CC cell proliferation and metastatic capabilities by inhibiting the PI3K/AKT/mTOR signaling pathway. In addition, rotenone inhibited tumor growth and metastatic capability of CC, which was confirmed in a xenograft mouse model. In conclusion, the present study revealed that rotenone inhibited CC cell viability, motility, EMT and metastasis in vitro and in vivo by inhibiting the PI3K/AKT/mTOR signaling pathway.

Epithelial-mesenchymal transition and metastasis of colon cancer cells induced by the FAK pathway in cancer-associated fibroblasts.

ObjectiveThe role and mechanism of tetrathiomolybdate (TM) in cancer-associated fibroblasts (CAFs) in colon cancer using three-dimensional (3D) culture were investigated, and the associations between the focal adhesion kinase (FAK) pathway and epithelial–mesenchymal transition (EMT) in CAFs were explored.MethodsA 3D co-culture model of colon cancer LOVO cells with CAFs and normal fibroblasts (NFs) was established using Matrigel as a scaffold material. The differential expression of LOXL2 (lysyl oxidase-like 2) in the supernatant of CAFs and NFs was determined using ELISA, and expression levels of EMT-related proteins and FAK signaling pathway-related proteins were determined using western blot.ResultsLOXL2 levels secreted by CAFs were higher compared with that secreted by NFs. In the CAF + LOVO group, compared with the LOVO group, E-cadherin expression decreased significantly, while N-cadherin and F-PAK expression increased significantly. TM results were opposite compared with the above results.ConclusionsCAFs stimulate EMT in human colon cancer LOVO cells by secreting LOXL2 to activate the FAK signaling pathway, thereby promoting tumor metastasis. TM inhibited the occurrence of EMT in the CAF-induced colon cancer LOVO cell line, thereby reducing the invasion and metastasis of colon cancer cells.

Roles of DANCR/microRNA-518a-3p/MDMA ceRNA network in the growth and malignant behaviors of colon cancer cells

BackgroundThe competing endogenous RNA (ceRNA) networks of long non-coding RNAs (lncRNAs) and microRNAs (miRs) have aroused wide concerns. The study aims to investigate the roles of lncRNA DANCR-associated ceRNA network in the growth and behaviors of colon cancer (CC) cells.MethodsDifferentially expressed lncRNAs between CC and paracancerous tissues were analyzed using microarrays and RT-qPCR. Follow-up studies were conducted to evaluate the correlation between DANCR expression and prognosis of CC patients. Loss-of-functions of DANCR were performed to identify its role in the malignant behaviors of CC cells. Sub-cellular localization of DANCR and the potential targets of DANCR were predicted and validated. Cells with inhibited DANCR were implanted into nude mice to evaluate the tumor formation and metastasis in vivo.ResultsDANCR was highly-expressed in CC tissues and cell lines, and higher levels of DANCR were linked with worse prognosis and less survival time of CC patients. Silencing of DANCR inhibited proliferation, viability, metastasis and resistance to death of CC cells. DANCR was found to be sub-localized in cytoplasmic matrix and to mediate murine double minute 2 (MDM2) expression through sponging miR-518a-3p in CC cells, during which the Smad2/3 signaling was activated. Likewise, silencing of DANCR in CC cells inhibited tumor formation and metastasis in vivo.ConclusionThis study provided evidence that silencing of DANCR might inhibit the growth and metastasis of CC cells through the DANCR/miR-518a-3p/MDM2 ceRNA network and the defect of Smad2/3 while activation of the p53 signaling pathways. This study may offer novel insights in CC treatment.

Long Non-Coding RNA LEF1-AS1 Promotes Migration, Invasion and Metastasis of Colon Cancer Cells Through miR-30-5p/SOX9 Axis.

IntroductionAberrant expression of long non-coding RNAs (lncRNAs) has been implicated in the tumorigenesis and progression of colon cancer. Lymphoid enhancer-binding factor 1 antisense RNA 1 (LEF1-AS1), a highly conserved and newly discovered long non-coding RNA, has been reported to be upregulated and correlated with poor prognosis in colon cancer, but the exact role of it remains uncertain.Materials and MethodsIn our study, the biological functions of LEF1-AS1 in colon cancer were analyzed by cell viability assay, colony formation assay, scratch wound healing assay, transwell cell invasion assay, soft agar assay, luciferase reporter assay, pull down assay, tumor xenograft model and Western blot.ResultsWe found that LEF1-AS1 was upregulated in colon cancer patients and correlated with poor overall survival and recurrent-free survival. Besides, enforced expression of LEF1-AS1 in HT29 and T84 cells promoted migration, invasion, anchorage-independent growth, tumor xenograft formation and lung metastasis, while knockdown of LEF1-AS1 in COLO320 cells suppressed cell migration, invasion, anchorage-independent growth and tumor xenograft formation. In addition, LEF1-AS1 was directly interacted and inversely correlated with miR-30-5p in colon cancer, and SOX9 was a downstream target for miR-30-5p. LEF1-AS1 overexpression increased the expression level of SOX9, and restoration of SOX9 attenuated the effects caused by LEF1-AS1 knockdown in cell migration, invasion, anchorage-independent growth and tumor xenograft formation.ConclusionOur results indicated that LEF1-AS1 promoted migration, invasion and metastasis of colon cancer cells partially through miR-30-5p/SOX9 axis. The oncogenic LEF1-AS1 could be a potential prognostic biomarker for colon cancer.

Jak-Stat Signaling Pathway Related Gene Expressions and Blood Biochemical indicators in Acute Promyelocytic Leukemia

Jak-Stat Signaling Pathway Related Gene Expressions and Blood Biochemical indicators in Acute Promyelocytic Leukemia

Norepinephrine‐CREB1‐miR‐373 axis promotes progression of colon cancer

The adrenergic system contributes to the stress‐induced onset and progression of cancer. Adrenergic fibers are the primary source of norepinephrine (NE). The underlying mechanisms involved in NE‐induced colon cancer remain to be understood. In this study, we describe the function and regulatory network of NE in the progression of colon cancer. We demonstrate that NE‐induced phosphorylation of cAMP response element‐binding protein 1 (CREB1) promotes proliferation, migration, and invasion of human colon cancer cells. The downstream effector of NE, CREB1, bound to the promoter of miR‐373 and transcriptionally activated its expression. miR‐373 expression was shown to be necessary for NE‐induced cell proliferation, invasion, and tumor growth. We confirmed that proliferation and invasion of colon cancer cells are regulated in vitro and in vivo by miR‐373 through targeting of the tumor suppressors TIMP2 and APC. Our data suggest that NE promotes colon cancer cell proliferation and metastasis by activating the CREB1–miR‐373 axis. The study of this novel signaling axis may provide mechanistic insights into the neural regulation of colon cancer and help in the design of future clinical studies on stress biology in colorectal cancer.

The function of Piezo1 in colon cancer metastasis and its potential regulatory mechanism

ObjectiveIncreasing evidence has revealed that mechanical stress and elevated mechanical signals promote malignant tumor transformation and metastasis. This study aimed to explore the function of the mechanically activated ion-channel Piezo1 in the colon cancer metastasis and its potential regulatory mechanism.MethodsFirst, we examined the expression levels of Piezo1 and mitochondrial calcium uniporter (MCU) both in colon cancer tissues and assessed the prognostic value of Piezo1 and MCU in a colon cancer cohort (n = 110). Second, functional assays were performed to investigate the effects of Piezo1 and MCU on colon cancer cell migration, invasion, and mitochondrial membrane potential. Third, we analyzed the expression of Piezo1, MCU, and HIF-1α by overexpressing/silencing each other’s expression.ResultsWe found that Piezo1 was up-regulated and MCU was down-regulated in colon cancer tissues. Piezo1 and MCU were both correlated with poor prognosis of patients with colon cancer. Overexpressing Piezo1 and silencing MCU could promote colon cancer cell migration and metastasis, reduce mitochondrial membrane potential, and promote each other’s expression. We also found that HIF-1α was up-regulated in colon cancer tissues. Additionally, silencing Piezo1 inhibited the expression of HIF-1α and VEGF, which was contrary to MCU silencing. Intriguingly, Piezo1-overexpressing cells did not regain their migration behaviors when HIF-1α expression was inhibited, which was accompanied with the re-expression of MCU and VEGF.ConclusionIn our study, Piezo1 is involved in colon cancer cell metastasis. Furthermore, our findings indicated a possible Piezo1-MCU-HIF-1α-VEGF axis, which still need further exploration.

Retraction: Neutrophil extracellular traps promote peritoneal metastasis of colon cancer cells.

[This retracts the article DOI: 10.18632/oncotarget.26664.].

Betulinic Acid Inhibits the Metastasis of Colon Cancer Cells through Regulating TGF-&amp;beta;/Smad Signaling Pathway

Betulinic Acid Inhibits the Metastasis of Colon Cancer Cells through Regulating TGF-&amp;beta;/Smad Signaling Pathway

RETRACTED ARTICLE: Silencing UNC5B antisense lncRNA 1 represses growth and metastasis of human Colon cancer cells via raising miR-622

We, the Editors and Publisher of the journal Artificial Cells, Nanomedicine, and Biotechnology, have retracted the following article: Yan Zhang, Zhen Li & Zhi Lan (2020) Silencing UNC5B antisense lncRNA 1 represses growth and metastasis of human Colon cancer cells via raising miR-622. Artificial Cells, Nanomedicine, and Biotechnology, 48(1), 60–67, DOI: 10.1080/21691401.2019.1699809 Since publication, concerns have been raised about the integrity of the data in the article. When approached for an explanation, the authors have been unable to verify their original data or answer our questions about research ethics and the informed consent process. We also have concerns regarding the integrity of the authorship, as one co-authors has stated they did not consent to being listed as an author. We are therefore retracting this article and all authors listed in this publication have been informed. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as ‘Retracted’.

Abstract B098: A novel monoclonal antibody for a cancer stem cell marker CD133 exerts antitumor and antimetastasis activities for colon cancers

Abstract Background: Cancer stem cells contribute to tumorigenesis, chemoresistance, and metastasis. CD133 is a pentaspan membrane glycoprotein, and is used for the isolation of stem-like cells from cancer tissues. However, specific and sensitive monoclonal antibodies (mAbs), which are useful in every application, such flow cytometry, Western blot, and immunohistochemical analyses have not been established. Furthermore, antibody drugs targeting CD133 have not been established. Purpose: We aimed to develop novel anti-CD133 mAbs, which not only are useful for all applications but also exerts anti-tumor and anti-metastasis activities. Methods: We employed Cell-Based Immunization and Screening (CBIS) method for the development of anti-CD133 mAbs. The full-length CD133-overexpressed LN229 glioblastoma cells were immunized into mice, and flow cytometry was used for the first screening. Western blot and immunohistochemical screenings were further performed. Human colon cancer cell lines were used for examining the anti-tumor and the anti-metastasis activities of anti-CD133 mAbs. Results: We established a novel anti-CD133 mAb, CMab-43 (IgG2a, kappa), which demonstrated a sensitive and specific reaction against colon cancer cells in flow cytometry, Western blot, and immunohistochemical analyses. CMab-43 showed cancer-specific staining patterns in colon cancer tissues. Furthermore, CMab-43 significantly reduced tumor development of colon cancer cell xenografts, and inhibited experimental metastasis of colon cancer cells. Conclusion: CMab-43, which was developed by CBIS method, is useful for many applications and exerts anti-tumor or anti-metastasis activities. CMab-43 could be advantageous for antibody therapy against CD133-expressing colon cancers. Citation Format: Yukinari Kato, Tomokazu Ohishi, Manabu Kawada, Mika K Kaneko. A novel monoclonal antibody for a cancer stem cell marker CD133 exerts antitumor and antimetastasis activities for colon cancers [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B098. doi:10.1158/1535-7163.TARG-19-B098

The miR-28-5p-CAMTA2 axis regulates colon cancer progression via Wnt/β-catenin signaling.

Colon cancer is the third most commonly diagnosed cancer with high morbidity and mortality. Calmodulin-binding transcription activator 2 (CAMTA2) belongs to the calmodulin-binding transcription activator protein family. The functional role of CAMTA2 in colon cancer development remains unclear. Our research found out that CAMTA2 was high-level expressed in colon cancer, and the upregulated CAMTA2 expression was markedly correlated with poor survival. Functional experiments showed that knockdown of CAMTA2 repressed colon cancer cell proliferation/migration in vitro and attenuated proliferation in vivo. In additional, CAMTA2 expression was controlled by miR-28-5p via posttranscriptional regulation and miR-28-5p expression was reversely correlated with CAMTA2 expression in colon cancer. Moreover, enforced miR-28-5p expression downregulated the expression of CAMTA2 significantly and the restoration of CAMTA2 expression abolished the inhibitory effect of miR-28-5p on colon cancer cell proliferation and metastasis. Mechanistically, overexpression of miR-28-5p suppressed Wnt/β-catenin signaling and the inhibitory could be partly abolished by overexpression of CAMTA2. In summary, our findings reveal that miR-28-5p/CAMTA2 axis plays a critical role in human colon cancer, which might be a promising diagnosis and therapeutic target for colon cancer treatment.

C-Fos separation from Lamin A/C by GDF15 promotes colon cancer invasion and metastasis in inflammatory microenvironment.

Inflammatory microenvironment is an important factor for promoting cancer invasion and metastasis, but the underlying molecular mechanisms remain unclear. Here, we mimicked an inflammatory microenvironment both in vitro and in vivo and investigated its effects on the invasion and metastasis of colon cancer. Moreover, colon cancer patient samples were also analyzed statistically. Conditioned medium from the differentiated macrophages induced invasion and migration of colon cancer cells in vitro, which could be reversed by the treatment of a neutralizing anti-growth differentiation factor 15 (GDF15) antibody, indicating GDF15 involvement in inflammation-induced invasiveness. Also, we observed similar effects of human recombinant GDF15 on colon cancer cells. Mechanistically, GDF15 activated c-Fos by separating it from Lamin A/C, increasing transcriptional activity of c-Fos and regulating EMT gene expressions. However, c-Fos knockdown using lentivirus shRNA plasmid inhibited GDF15-triggered invasion and migration in vitro. In vivo, inflammation caused by lipopolysaccharides obviously increased GDF15 secretion, and c-Fos knockdown reduced the lung metastasis of colon cancer cells in mice model. In addition, c-Fos expressions in patient samples were found to be associated with colon cancer metastasis and TNM stages. Taken together, GDF15 in inflammatory microenvironment induces colon cancer invasion and metastasis by regulating EMT genes by activating c-Fos, which might be a potential therapeutic target for metastatic colon cancer.

307 Transgelin Regulates Colon Cancer Cell Invasion by Interacting With PARP1 and Activating Rho Signaling Pathway: A Bioinformatics Analysis

INTRODUCTION: Our previous studies found that Transgelin was up-regulated in node-positive colorectal cancer versus in node-negative disease. Transgelin, an actin-binding protein, is associated with the remodeling of cytoskeleton in the cytoplasm. However, we found that Transgelin had nuclear localization in colon cancer cells and gene expression profiling identified that TAGLN over-expression affected the expression of 256 downstream genes closely related to cell morphology, migration and invasion. In addition, we found that Transgelin could interact with 297 proteins by immunoprecipitation and liquid chromatography -mass spectrometry. Thus, we speculate that Transgelin may play different roles in the nucleus and the cytoplasm, which collaboratively participate in the invasion and metastasis of colon cancer cells. METHODS: 256 downstream genes regulated by Transgelin were analyzed by bioinformatics analysis. Transgelin has been found to regulate colon cancer metastasis through specific key genes and signaling pathways. Then, by analyzing the promoter regions of these key genes, a protein has been predicted to be the transcription factor of these genes. Further, by comparing the 297 proteins that have been previously detected to potentially interact with Transgelin, we found that the predicted transcription factor fell in this pool. Finally, we verified the interaction between Transgelin and this transcription factor by immunoprecipitation and Western blotting. RESULTS: Over-expression of TAGLN could lead to differential expression of 184 downstream genes. By constructing the network of gene-encoded proteins, we conducted network topology analysis and identified the key genes, including CALM1, MYO1F, NCKIPSD, PLK4, RAC1, WAS and WIPF1 (Figure 1). They are mainly involved in the Rho signaling pathway which is related to oncogenesis and tumor metastasis. In addition, bioinformatics analysis (GCBI tools) showed that all of the promoter regions of the key genes had binding sites with PARP1 protein. And PARP1 also fell in the 297 proteins that have been previously detected to interact with Transgelin. Thus, PARP1 protein was selected as a potential transcription factor. Immunoprecipitation validated that PARP1 interacted with Transgelin in RKO human colon cancer cells. CONCLUSION: Bioinformatics analysis revealed that Transgelin may activate the Rho signaling pathway in promoting colon cancer metastasis by interacting with PARP1.

637P - RBP-Jκ in colon cancer cells facilitates tumour associated macrophages (TAMs)-induced cell metastasis by secreting CXCL11

BackgroundMetastasis is the main cause of death in colon cancer patients. RBP-Jκ, which is the main transcription mediator of Notch signaling, is involved in colon cancer development but its function in colon cancer metastasis is still unclear. Here we aimed to find out the function of RBP-Jκ in colon cancer metastasis and its underlying mechanisms of modulating the interaction between colon cancer cells and tumor- associated macrophages (TAMs). MethodsCell migration, invasion and epithelial to mesenchymal transition (EMT) were used to reflect cell metastasis ability. A oc-culture system was adopted to research the mutual regulation between colon cancer cells and TAMs. Gain- and loss-of-function experiments and TGF-β/Smad3 pathway activator and inhibitor were used to determine the underlying mechanisms of RBP-Jκ and TAMs in regulating colon cancer metastasis in vitro and in vivo. RNA sequencing was performed to find out the regulating factor between colon cancer cell and TAMs. RBP-Jκ and E-cadherin expression and TAMs infiltration were examined in 201 colon cancer patients by immunohistochemical assay and were analyzed combined with clinical parameters. ResultsRBP-Jκ and TAMs promoted colon cancer cell metastasis through the TGF-β/Smad3 pathway and secreting of TGF-β, respectively. RBP-Jκ in colon cancer cell facilitated TAMs to secret TGF-β through secreting CXCL11. RBP-Jκ and E-cadherin was highly expressed in colon cancer tissues and para-tumor tissues, respectively. And there are more TAMs infiltrated in colon cancer tissues. RBP-Jκ expression and TAMs infiltration were negatively associated with E-cadherin expression and overall survival and positively associated with metastasis. RBP-Jκ and E-cadherin expression and TAMs infiltration were independent prognostic factors in colon cancer patients. ConclusionsOur research demonstrated that colon cancer cells with high RBP-Jκ expression secreted CXCL11 to enhance TGF-β secretion of TAMs which facilitated colon cancer metastasis. RBP-Jκ exrpression and TAMs infiltration were associated with colon cancer metastasis and acted as prognostic factors. Legal entity responsible for the studyWenjuan Wang. FundingNational Natural Science Foundation of China (No. 81502099); Key laboratory of tumor precision medicine open project of Shaanxi province (No. KLTPM-SX2018-B3); The scientific research fund of the first affiliated hospital of Xi’an Jiaotong University (2018MS-06). DisclosureAll authors have declared no conflicts of interest.

Crumbs3 regulates the expression of glycosphingolipids on the plasma membrane to promote colon cancer cell migration

The cell polarity regulator Crumbs3 (Crb3) promotes colon cancer cell migration and metastasis. However, the underlying mechanism of cancer cell migration regulated by Crb3 has not been fully elucidated. Here, we demonstrated that Crb3 is associated with cell migration by regulating glycosphingolipid (GSL) expression in human colon cancer cells. Crb3-knockout (KO) cells showed a remarkable increase in ganglioside GM3 (GM3) on the cell surface. Reduced migration by Crb3-KO cells was restored by forced expression of both Crb3 and Neuraminidase3 (Neu3). Immunofluorescent staining revealed that most Crb3 is colocalized with the recycling endosome marker Rab11. These findings show that Crb3 may promote colon cancer cell migration by regulating the expression of GSLs on the cell surface.

ACLY facilitates colon cancer cell metastasis by CTNNB1

BackgroundColon cancer is the second leading cancer worldwide. Recurrent disease and chemotherapeutic drug resistance are very common in the advanced stage of colon cancer. ATP-citrate lyase (ACLY), the first-step rate-controlling enzyme in lipid synthesis, is elevated in colon cancer. However, it remains unclear about the exact role of ACLY in the development of colon cancer metastasis.MethodsTo evaluate the role of ACLY in colon cancer metastasis, we performed cell migration and invasion assays in two ACLY-deficient colon cancer cell lines. Colon cancer mouse model is used to examine ACLY’s effects on colon metastasis potentials in vivo. We analyzed the correlation between ACLY and CTNNB1 protein in 78 colon cancer patients by Pearson correlation. To finally explore the relationship of ACLY and CTNNB1, we used western blots, migration and invasion assays to confirm that ACLY may regulate metastasis by CTNNB1.ResultsOur data showed that the abilities of cell migration and invasion were attenuated in ACLY-deficient HCT116 and RKO cell lines. Furthermore, we describe the mechanism of ACLY in promoting colon cancer metastasis in vitro and in vivo. ACLY could stabilize CTNNB1 (beta-catenin 1) protein by interacting, and the complex might promote CTNNB1 translocation through cytoplasm to nucleus, subsequently promote the CTNNB1 transcriptional activity and migration and invasion abilities of colon cancer cells. Immunohistochemical analysis of 78 colon cancer patients showed that the high expression levels of ACLY and CTNNB1 protein was positively correlated with metastasis of colon cancer.ConclusionsThese results shed new light on the molecular mechanism underlying colon cancer metastasis, which might help in improving therapeutic efficacy.