Epithelial-mesenchymal Transition In Cancer Cells Research Articles

Acquisition of Doxorubicin Resistance Induces Breast Cancer Cell Migration and Epithelial-Mesenchymal Transition that are Reversed by Shikonin-Metformin Synergy

Background: Drug resistance is a major challenge in cancer chemotherapy. Methods: By adopting an appropriately timed strategy, we generated MCF-7 cell sublines resistant to serial doses of doxorubicin (DOX). Our higher-dose sublines showed more stability in resistance and were, therefore, subjected to further analyses. We tested the consistency of drug resistance by comparing sublines with control groups for growth and migration capacities. Molecular analyses monitored expression changes, CD44/CD24 ratios, and DOX binding to key molecules. The reverting impact of shikonin (SHKN) and metformin (MTFN) on DOX resistance was examined. Results. The resistant sublines grew parallel to or even faster than WT MCF-7 cells and showed a larger and more rounded morphology. The consistency of their drug resistance and invasive potential was demonstrated over time using serial doses of DOX. Real-time PCR revealed upregulation of genes involved in cell growth and survival, drug resistance, migration/invasion, and epithelial-mesenchymal transition and, conversely, downregulation of pro-apoptotic, anti-chemoresistance, and tumor suppressor genes. SHKN-MTFN co-treated resistant cells showed significantly lower CD44/CD24 ratios, less aggressiveness, and reduced survival and migration rates but enhanced apoptosis. SHKN’s affinity to CYP1A and TOP2A demonstrated the importance of these interactions and the compounds’ capacity to compete with DOX. Conclusion: Acquisition of DOX resistance increases tumorigenic properties of cancer cells, whereas synergy between selective anti-tumorigenic compounds re-sensitizes resistant cells by reverting cellular pathways that favor or follow resistance. Our findings suggest that this reversal is supported by competing reactions that deprive DOX of binding to its target molecules.

Tumour-derived exosome SNHG17 induced by oestrogen contributes to ovarian cancer progression via the CCL13-CCR2-M2 macrophage axis.

Oestrogen is known to be strongly associated with ovarian cancer. There was much work to show the importance of lncRNA SNHG17 in ovarian cancer. However, no study has revealed the molecular regulatory mechanism and functional effects between oestrogen and SNHG17 in the development and metastasis of ovarian cancer. In this study, we found that SNHG17 expression was significantly increased in ovarian cancer and positively correlated with oestrogen treatment. Oestrogen could promote M2 macrophage polarization as well as ovarian cancer cells SKOV3 and ES2 cell exosomal SNHG17 expression. When exposure to oestrogen, exosomal SNHG17 promoted ovarian cancer cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) invitro, and tumour growth and lung metastasis invivo by accelerating M2-like phenotype of macrophages. Mechanically, exosomal SNHG17 could facilitate the release of CCL13 from M2 macrophage via the PI3K-Akt signalling pathway. Moreover, CCL13-CCR2 axis was identified to be involved in ovarian cancer tumour behaviours driven by oestrogen. There results demonstrate a novel mechanism that exosomal SNHG17 exerts an oncogenic effect on ovarian cancer via the CCL13-CCR2-M2 macrophage axis upon oestrogen treatment, of which SNHG17 may be a potential biomarker and therapeutic target for ovarian cancer responded to oestrogen.

The Evaluation of the N-cadherin Promoter’s ability to Block EMT by Specific Expression of Diphtheria Toxin in EMT-induced A549 Cell Lines

During epithelial to mesenchymal transition, the ability of cancer cells to transform and metastasize is primarily determined by N-cadherin-mediated migration and invasion. This study aimed to evaluate whether the N-cadherin promoter can induce diphtheria toxin expression as a suicide gene in epithelial to mesenchymal transition (EMT)-induced cancer cells and whether this can be used as potential gene therapy.
 To investigate the expression of diphtheria toxin under the N-cadherin promoter, the promoter was synthesized, and was cloned upstream of diphtheria toxin in a pGL3-Basic vector. The A-549 cells was transfected by electroporation. After induction of EMT by TGF-β and hypoxia treatment, the relative expression of diphtheria toxin, mesenchymal genes such as N-cadherin and Vimentin, and epithelial genes such as E-cadherin and β-catenin were measured by real-time PCR. MTT assay was also performed to measure cytotoxicity. Finally, cell motility was assessed by the Scratch test.
 After induction of EMT in transfected cells, the expression of mesenchymal markers such as Vimentin and N-cadherin significantly decreased, and the expression of β-catenin increased. In addition, the MTT assay showed promising toxicity results after induction of EMT with TGF-β in transfected cells, but toxicity was less effective in hypoxia. The scratch test results also showed that cell movement was successfully prevented in EMT-transfected cells and thus confirmed EMT occlusion.
 Our findings indicate that by using structures containing diphtheria toxin downstream of a specific EMT promoter such as the N-cadherin promoter, the introduced toxin can kill specifically and block EMT in cancer cells.

Abstract LB370: Exploring SLC35B family genes in colorectal carcinoma: Bioinformatics and functional insights into prognosis and therapy

Abstract Colorectal carcinoma (CRC) poses a significant health challenge, with recent therapeutic advances yet to substantially improve long-term patient survival. Central to this study is the SLC35B gene family (SLC35B1-4), which encodes nucleotide sugar transporters essential to cellular membranes. Emerging research highlights a link between these transporters' dysfunction and the development and progression of tumors, yet the specific role of the SLC35B family in CRC remains unclear. Our investigation delves into the function of SLC35B genes in CRC, utilizing an integrated bioinformatics approach with databases like GENT2, TCGA, UALCAN, cBioportal, TIMER, and Kaplan-Meier plotter. Our analysis reveals a notable upregulation of SLC35B1/2/4 mRNA in CRC tissues compared to adjacent non-tumor tissues, with a concurrent downregulation of SLC35B3. Promoter methylation analysis shows increased methylation for SLC35B1/3/4, while SLC35B2 demonstrates decreased methylation. According to GEO and TCGA data, CRC patients exhibiting high SLC35B4 expression face lower survival rates. Multivariate Cox regression analysis confirms high SLC35B4 expression as an independent risk factor. Further, SLC35B4 expression correlates with increased infiltration of immune cells, particularly macrophages, and aligns positively with immune checkpoints such as CD274 and HAVCR2. In vitro assays link SLC35B4 to enhanced cancer cell proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT). In vivo, SLC35B4 knockdown leads to reduced tumor growth in mouse xenograft models. RNA sequencing identifies 241 genes differentially expressed in SLC35B4 knockdown compared to control cells, with Gene Set Enrichment Analysis (GSEA) associating SLC35B4 with the PI3K-Akt signaling pathway. In summary, our research sheds light on the SLC35B gene family's role in CRC, especially SLC35B4, highlighting its potential as both a prognostic marker and a therapeutic target in CRC, particularly through its involvement in the PI3K-Akt signaling pathway. Citation Format: Yu-Jia Chang, Chang-Chun Yang, Cheng-Chin Lee, Chien-Yu Huang. Exploring SLC35B family genes in colorectal carcinoma: Bioinformatics and functional insights into prognosis and therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB370.

The Differential Effect of Senolytics on SASP Cytokine Secretion and Regulation of EMT by CAFs.

The tumor microenvironment (TME) plays an essential role in tumor progression and in modulating tumor response to anticancer therapy. Cellular senescence leads to a switch in the cell secretome, characterized by the senescence-associated secretory phenotype (SASP), which may regulate tumorigenesis. Senolytic therapy is considered a novel anticancer strategy that eliminates the deleterious effects of senescent cells in the TME. Here, we show that two different types of senolytic drugs, despite efficiently depleting senescent cells, have opposite effects on cancer-associated fibroblasts (CAFs) and their ability to regulate epithelial-mesenchymal transition (EMT). We found that senolytic drugs, navitoclax and the combination of dasatinib/quercetin, reduced the number of spontaneously senescent and TNF-induced senescent CAFs. Despite the depletion of senescent cells, the combination of dasatinib/quercetin versus navitoclax increased the secretion of the SASP pro-inflammatory cytokine IL-6. This differential effect correlated with the promotion of enhanced migration and EMT in MC38 colorectal cancer cells. Our results demonstrate that some senolytics may have side effects unrelated to their senolytic activity and may promote tumorigenesis. We argue for more careful and extensive studies of the effects of senolytics on various aspects of tumor progression and tumor resistance to therapy before the senolytic strategy is implemented in the clinic.

MSLN induced EMT, cancer stem cell traits and chemotherapy resistance of pancreatic cancer cells

Chemoresistance is one of the main reasons for poor prognosis of pancreatic cancer. The effects of mesothelin (MSLN) on chemoresistance in pancreatic cancer are still unclear. We aim to investigate potential roles of MSLN in chemoresistance and its relationship with proliferation, epithelial-mesenchymal transition (EMT) and cancer stemness of pancreatic cancer cells. Human pancreatic cancer cell lines ASPC-1 and Mia PaCa-2 with high and low expression of MSLN, respectively, were selected. The ASPC-1 with MSLN knockout (KO) and Mia PaCa-2 of MSLN overexpression (OE) were generated. The effects of MSLN on cell phenotypes, expression of EMT-related markers, clone formation, tumor sphere formation, and pathologic role of MSLN in tumorigenesis were detected. Sensitivity of tumor cells to gemcitabine was evaluated. The results showed that adhesion, proliferation, migration and invasion were decreased significantly in ASPC-1 with MSLN KO, whereas increased significantly in Mia PaCa-2 with MSLN OE. The size and the number of clones and tumor spheres were decreased in ASPC-1 with MSLN KO, and increased in Mia PaCa-2 with MSLN OE. In xenograft model, tumor volume was decreased (tumor grew slower) in MSLN KO group compared to control group, while increased in MSLN OE group. Mia PaCa-2 with MSLN OE had a higher IC50 of gemcitabine, while ASPC-1 with MSLN KO had a lower IC50. We concluded that MSLN could induce chemoresistance by enhancing migration, invasion, EMT and cancer stem cell traits of pancreatic cancer cells. Targeting MSLN could represent a promising therapeutic strategy for reversing EMT and chemoresistance in pancreatic cancer cells.

The mechanism by which SIRT1 regulates autophagy and EMT in drug-resistant oesophageal cancer cells

Cancer cell resistance presents a significant clinical challenge. The mechanisms underlying drug resistance in cancer cells are intricate and remain incompletely understood. Notably, tumor cell resistance often coincides with the epithelial-mesenchymal transition (EMT).In this study, we observed an elevation in autophagy levels following the development of drug resistance in oesophageal cancer cells. Inhibition of autophagy led to a reduction in drug-resistant cell migration and the inhibition of EMT.Furthermore, we identified an upregulation of SIRT1 expression in drug-resistant oesophageal cancer cells. Subsequent inhibition of SIRT1 expression in drug-resistant cells resulted in the suppression of autophagy levels, migration ability, and the EMT process.Our additional investigations revealed that a SIRT1 inhibitor effectively curbed tumor growth in human oesophageal cancer xenograft model mice (TE-1, TE-1/PTX) without evident toxic effects. This mechanism appears to be associated with the autophagy levels within the tumor tissue.

Ezetimibe inhibits the migration and invasion of triple-negative breast cancer cells by targeting TGFβ2 andEMT.

The important role of cholesterol in tumor metastasis has been widely studied in recent years. Ezetimibe is currently the only selective cholesterol uptake inhibitor on the market. Here, we explored the effect of ezetimibe on breast cancer metastasis by studying its impact on breast cancer cell migration, invasion, and epithelial-mesenchymal transition (EMT). Differential gene expression analysis and validation were also carried out to compare ezetimibe-treated and untreated breast cancer cells. Finally, breast cancer cells overexpressing TGFβ2 were constructed, and the effect of TGFβ2 on the migration and invasion of ezetimibe-treated breast cancer cells was examined. Our results show that ezetimibe treatment of breast cancer cells inhibited cell migration, invasion, and EMT, and it significantly suppressed the expression of TGFβ2. Overexpression of TGFβ2 reversed the inhibitory effect of ezetimibe on the migration and invasion of breast cancer cells. Taken together, our results suggest that ezetimibe might be a potential candidate for the treatment of breast cancer metastasis.

Abstract 1568: Her2 promotes early dissemination of breast cancer by suppressing the p38 pathway through upregulation of Wip1

Abstract (a)Metastasis is the leading cause of cancer-related deaths. Increasing evidence shows that cancer cells can disseminate from early primary lesions that are impalpable, but the pathways are poorly understood. Her2 promotes breast cancer early dissemination by suppressing p38, but how Her2 downregulates p38 is unclear. In this study, we investigated the mechanism underlying suppression of p38 by Her2 in breast cancer early dissemination using cell models and xenograft models of early lesions of breast cancer. (b)We studied the role of Wip1, a p38 phosphatase, in disseminating phenotypes in cell line models of breast cancer early lesions, including cell motility measured in transwell assays, cell invasion measured by percentage of organoids with outward invading cells, and epithelial-to-mesenchymal transition (EMT) measured by levels of EMT markers in Western blotting analysis and immunofluorescence (IF) staining assays. (c)We demonstrate that high levels of Wip1 correlated with Her2+ status, and reduced phosphorylation of p38 and its downstream effectors MK2 and Hsp27 in tissue samples from early lesions of human breast cancer. In addition, ectopic expression of Wip1 reduced phosphorylation of p38, MK2 and Hsp27 in cell models of breast cancer early lesions.We found that Wip1 promoted migration, invasion and EMT, while Wip1 knockdown abrogated the ability of Her2 to induce these disseminating phenotypes, in cell line models of early lesion breast cancer. Thus, Wip1 induction is both sufficient, and necessary for Her2, to promote migration, invasion and EMT in early lesion breast cancer cells. In an attempt to identify the Wip1 downstream effectors involved in disseminating phenotypes, we found that ectopic expression of the constitutively active mutants of p38 reversed the ability of Wip1 to suppress MK2 and Hsp27 phosphorylation and to induce migration, invasion and EMT in early lesion breast cancer cells. These results suggest that Wip1 promotes breast cancer early dissemination by suppressing p38. We investigate the mechanism by which Her2 induces Wip1 expression. Ectopic expression of Her2 did not alter the level of Wip1 mRNA or the Wip1 protein stability, suggesting that Her2 promote Wip1 expression by regulating its translation. We are currently investigating the mechanism by which Her2 induces Wip1 translation.Moreover, inhibitors of Her2, Wip1 and Skp2 can each reduce the disseminating phenotypes in cells models of breast cancer early lesions ectopically expressing Her2, Wip1 or Skp2. (d)Our findings identify the Her2-Wip1-p38-Mk2-Hsp27 cascade as a novel mechanism mediating breast cancer early dissemination and provide a basis for new therapies targeting early metastatic dissemination in Her2+ breast cancer using inhibitors for Her2, Wip1 or Skp2. Citation Format: Nan Wang. Her2 promotes early dissemination of breast cancer by suppressing the p38 pathway through upregulation of Wip1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1568.

Abstract 203: Promotion of metastasis of ERBB2-positive breast cancer by mesenchymal stem cells via exosomes-mediated activation of ERBB2/ERBB3→PI3K/Akt singaling pathway

Abstract Elevated expression of ERBB3 receptor correlates with increased distant metastasis of breast cancers with amplification and/or overexpression of ERBB2 (HER2/neu), which the underlying molecular mechanism remains unclear. In recent years, cumulative studies have demonstrated that mesenchymal stem cells (MSCs), one of the important cellular components in tumor microenvironment, play important roles in multiple hallmarks of cancer including invasion and metastasis. However, its role in metastasis of ERBB2-positive breast cancer as well as the precise mechanisms are largely unrevealed. In our current study, we found that co-culture with MSCs or treatment with exosomes derived from MSCs can significantly promote the epithelial-mesenchymal transition (EMT), migration and invasion of ERBB2-positive breast cancer cells. MSCs exhibited significantly higher expression of NRG-1, a known ligand of ERBB3, as compared with ERBB2-positive breast cancer cells. The presence of NRG-1 in exosomes derived from MSCs was also evidenced. Mechanistically, co-culture with MSCs or treatment with exosomes derived from MSCs induced upregulation of ZEB1 and Slug via activation of downstream PI3K/Akt singaling to promote EMT of ERBB2-positive breast cancer cells. In addition, the expression of MMP2 was also upregulated by treatment with MSCs-derived exosomes, which enhanced the migration and invasion of ERBB2-positive breast cancer cells simultaneously. Interestingly, our study further demonstrated that treatment with MSCs-derived exosomes could significantly downregulate the expression of PTEN, the key negative regulator of PI3K/Akt singaling, via transferring three PTEN-targeting miRNAs (miR-21-5p, miR-23a-3p, and miR-148a-3p). Taken together, we presented here that MSCs may, on the one hand, directly activate the ERBB2/ERBB3→PI3K/Akt signaling pathway in ERBB2-positive breast cancer cells through the expression and secretion of NRG-1 via exosomes. Meanwhile, miR-21-5p, miR-23a-3p, and miR-148a-3p targeted delivery by exosomes specifically downregulated the expression of PETN, thus reliefs the negative regulation of PI3K/Akt signaling in ERBB2-positive breast cancer cells. These effects of MSCs act in concert to promote the metastasis of ERBB2-positive breast cancer. Our study lays a theoretical foundation and preliminary experimental basis for the development of novel combined therapies for patient with ERBB2-positive breast cancer through co-targeting MSC-derived NRG-1 and miR-21-5p, miR23a-3p, miR148a-3p/PTEN axis in tumor microenvironment in the future. Citation Format: Yating Wu, Li Chen, Yue Cao, Qinfeng Huang, Huimin Niu, Xiaofeng Lai, Meng Zhao, Huihui Yan, Hui Lyu, Bolin Liu, Shenghang Zhang, Shuiliang Wang. Promotion of metastasis of ERBB2-positive breast cancer by mesenchymal stem cells via exosomes-mediated activation of ERBB2/ERBB3→PI3K/Akt singaling pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 203.

Abstract 1821: Conessine inhibits cell proliferation, migration and invasion, and induces apoptosis in liver cancer cells

Abstract Cancer-related deaths from hepatocellular carcinoma (HCC) rank first worldwide. Although many attempts have been made to treat HCC, the survival rate remains unsatisfactory. Many plants from the family Apocynaceae, such as Holarrhena floribunda, contain conessine, a steroidal alkaloid. Several studies have indicated that conessine acts as an antihistamine with cancer therapy and antimicrobial resistance, but it hasn't been tested for its anti-cancer activity against liver cancer. Our study aimed to investigate the anticancer properties of conessine against liver cancer. We tested the effects of conessine on cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) markers using both Huh7 and Mahlavu cells. Our experimental results indicated that conessine inhibited cell proliferation, migration, motility, and invasion in Huh7 and Mahlavu cells. Results of Western blot analysis showed that conessine induced apoptosis and EMT in liver cancer cells. Taken together, our results demonstrated that conessine exhibits anticancer activity in liver cancer through suppressing cell proliferation, migration, and invasion, and inducing apoptosis, suggesting it may have benefits for liver cancer treatment. Citation Format: Chia-Yang Li, Yu-Sheng Lin. Conessine inhibits cell proliferation, migration and invasion, and induces apoptosis in liver cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1821.

Abstract 6868: Exploring myeloid landscapes according to EGFR mutated NSCLC tumor microenvironment

Abstract Introduction: Although the use of immune checkpoint inhibitors (ICIs) has improved the survival rate of some patients, EGFR mutant (MT) NSCLC patients exhibit a poor response to ICIs compared to EGFR wild-type (WT) patients. It has been demonstrated that EGFR MT NSCLC cells contribute to immunosuppressive tumor microenvironments (TMEs) by secreting inhibitory cytokines and metabolites and recruiting pro-tumor immunogenic cells, thereby diminishing ICI efficacy. In particular, myeloid cells represent a major component of the TME and are involved in regulating tumor progression and metastasis, indicating anti- and pro-inflammatory heterogeneous functions. While single-cell based analyses have been conducted in various cell types, studies on the diversity of myeloid cells between EGFR WT and EGFR MT NSCLCs are insufficient. Therefore, we explored to reveal the presence of multifaceted myeloid cell populations and to modulate its functions to augment ICI response in NSCLC patients with EGFR MT using single-cell RNA analysis. Methods: Using the 10x Genomics Chromium system, we have generated single-cell RNA expression of a total of 904,174 cells from primary lung tissues of 95 patients with EGFR-WT (n=35), EGFR-MT TKI naïve (n=55), TKI post (n=5) and matched normal (n=22). Nine distinct cell lineages were annotated with canonical marker gene expression, focusing particularly on the myeloid (n=212,673 cells). Results: We characterized 22 transcriptional states of myeloid cells: 4 clusters of alveolar macrophages (AMs; PPARG+), 4 clusters of interstitial macrophages (IMs; SPP1+, FOLR2+, CCL2+), 4 clusters of conventional DCs (cDCs; CLEC9A+, CD1C+, LAMP3+), 2 clusters of mast cells (KIT+), 1 cluster of plasmacytoid DCs (pDCs; LILRA4+), proliferating cells (MKI67+), monocytes (FCN1+), neutrophil like cells (CSF3R+) and 4 other unidentified clusters. In tumor tissues, IMs constituted a significantly higher proportion compared to normal tissues (p<0.001), with EGFR-WT and EGFR-MT IMs exhibiting distinct characteristics. EGFR-WT IMs had a high proportion of cluster expressing FOLR2, a marker of tissue resident macrophages associated with CD8 T cell infiltration and activation. On the other hand, a major component of IMs from EGFR-MT was a cluster expressing SPP1 and its regulator MIF. SPP1 is well known to be involved in cancer cell progression, epithelial-mesenchymal transition, autophagy, and epigenetic alterations. The abundance of SPP1 IMs in the EGFR-MT TME refers to the formation of an immunosuppressive TME, potentially compromising the effectiveness of ICIs. Conclusions: We found that EGFR-MT TME comprised a high proportion of immunosuppressive IM cluster expressing SPP1, implying that it contributes to an immunosuppressive TME. Our findings suggest the possibility of developing strategies to enhance ICI responses by targeting SPP1-induced immunosuppressive TME in EGFR-mutant NSCLC patients. Citation Format: Eun Ji Lee, Juwon Ahn, You Won Lee, Minyeop Kim, Seung Yeon Oh, Yong Joon Park, Su-Jin Choi, JuHyeon Lee, Kyumin Lim, Kyoung-Ho Pyo, Jae Hwan Kim, Jii Bum Lee, Min Hee Hong, Sun Min Lim, Mi Ran Yun, Byoung Chul Cho. Exploring myeloid landscapes according to EGFR mutated NSCLC tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6868.

Unraveling the molecular mechanisms of lymph node metastasis in ovarian cancer: focus on MEOX1

BackgroundLymph node metastasis (LNM) is a major factor contributing to the high mortality rate of ovarian cancer, making the treatment of this disease challenging. However, the molecular mechanism underlying LNM in ovarian cancer is still not well understood, posing a significant obstacle to overcome.ResultsThrough data mining from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, we have identified MEOX1 as a specific gene associated with LNM in ovarian cancer. The expression of MEOX1 was found to be relatively high in serous ovarian adenocarcinoma, and its higher expression were associated with increased tumor grade and poorer clinical prognosis for ovarian cancer patients. Bioinformatics analysis revealed that MEOX1 exhibited the highest mRNA levels among all cancer types in ovarian cancer tissues and cell lines. Furthermore, gene set enrichment analysis (GSEA) and pathway analysis demonstrated that MEOX1 was involved in various LNM-related biological activities, such as lymphangiogenesis, lymphatic vessel formation during metastasis, epithelial-mesenchymal transition (EMT), G2/M checkpoint, degradation of extracellular matrix, and collagen formation. Additionally, the expression of MEOX1 was positively correlated with the expression of numerous prolymphangiogenic factors in ovarian cancer. To validate our findings, we conducted experiments using clinical tissue specimens and cell lines, which confirmed that MEOX1 was highly expressed in high-grade serous ovarian cancer (HGSOC) tissues and various ovarian cancer cell lines (A2780, SKOV3, HO8910, and OVCAR5) compared to normal ovarian tissues and normal ovarian epithelial cell line IOSE-80, respectively. Notably, we observed a higher protein level of MEOX1 in tumor tissues of LNM-positive HGSOC compared to LNM-negative HGSOC. Moreover, our fundamental experiments demonstrated that suppression of MEOX1 led to inhibitory effects on ovarian cancer cell proliferation and EMT, while overexpression of MEOX1 enhanced the proliferation and EMT capacities of ovarian cancer cells.ConclusionsThe results of our study indicate that MEOX1 plays a role in the lymph node metastasis of ovarian cancer by regulating multiple biological activities, including the proliferation and EMT of ovarian cancer, lymphangiogenesis, and ECM remodeling. Our findings suggest that MEOX1 could serve as a potential biomarker for the diagnosis and treatment of ovarian cancer with LNM.

Canonical DDR activation by EMT inducing agent 5-Fluorouracil is modulated by a cannabinoid based combinatorial approach via inducing autophagy and suppression of vimentin expression

Anastasis cascade including induction of Epithelial to Mesenchymal Transition (EMT), DNA repair, and stimulation of pro-survival mediators collectively exaggerate therapy resistance in cancer prognosis. The extensive implications of DNA-damaging agents are clinically proven futile for the rapid development of disease recurrence during treatment regime. Herein we report a glycosidic derivative of Δ9-tetrahydrocannabinol (THC-9-OG) abrogates sub-toxic doses of 5-Fluorouracil (5FU) induced EMT in colon cancer cells nullifying DNA repairing mechanism. Our in vitro and in vivo data strongly proclaims that THC-9-OG could not only abrogate 5FU mediated background EMT activation through stalling matrix degradation as well as murine 4T1 lung metastasis but also vigorously diminished Rad-51 repairing mediator along with stimulation of γ-H2AX foci formation. The combinatorial treatment (5FU + THC-9-OG) in Apc knockout colorectal carcinoma model conferred remission of the crypt progenitor phenotype which was prominently identified in 5FU treatment. Mechanistically, we demonstrated that 5FU plus THC-9-OG significantly attenuated major EMT inducer Vimentin via extensive ROS generation along with autophagy induction via LC3B I-II conversion and p62 degradation in a p-ATM dependent manner. Additionally, Cannabinoid receptor CB1 was responsible for abrogation of Vimentin since we found increase in the expression of γH2AX and decrease in vimentin expression in CB1 agonist (ACEA) plus 5FU treated cells. Nutshell, our results unveil a new direction of Cannabinoid based combinatorial approach to control background EMT along with robust enhancing of DNA damage potential of sub-toxic concentration of 5FU resulting immense inhibition of distant metastasis coupled with triggering cell death in vitro and in vivo.

SORBS1 inhibits epithelial to mesenchymal transition (EMT) of breast cancer cells by regulating PI3K/AKT signaling and macrophage phenotypic polarization.

This study aimed to explore the regulatory role of SORBS1 in macrophage polarization and the PI3K/AKT signaling pathway, as well as analyze its mechanism in epithelial-mesenchymal transition (EMT) of breast cancer cells. We established SORBS1-overexpressing and knockout cell lines and verified the effects of SORBS1 on cell viability, invasion, and migration by phenotyping experiments and assaying the expression of associated proteins. Furthermore, we established a breast cancer cell and macrophage co-culture system to validate the effect of SORBS1 expression on macrophage polarization and killing of breast cancer cells. Bioinformatics analysis showed that SORBS1 was lowly expressed in breast cancer (BRCA) samples and highly expressed in healthy tissues. Decreased SORBS1 expression was associated with poor prognosis, and the PI3K/AKT signaling pathway was the most significantly enriched pathway. In vitro experiments showed that high expression of SORBS1 inhibited the migration of breast cancer cells, as well as the PI3K/AKT signaling pathway, and blocked EMT of these cells. In addition, SORBS1 induced macrophage polarization to the M1-type and enhanced the killing effect on breast cancer cells in the co-culture system. In conclusion, we successfully verified that SORBS1 inhibits the invasion and migration of breast cancer cells, induces macrophage M1-type polarization, and blocks EMT of breast cancer cells, and it may act by regulating the PI3K/AKT signaling pathway.

Progerin Inhibits the Proliferation and Migration of Melanoma Cells by Regulating the Expression of Paxillin.

Progerin, the underlying cause of Hutchinson-Gilford Progeria Syndrome (HGPS), has been extensively studied for its impact on normal cells and premature aging patients. However, there is a lack of research on its specific effects on tumor cells. Melanoma is one of the most common malignant tumors with high morbidity and mortality. This study aimed to elucidate the potential therapeutic role of progerin in melanoma. We constructed the melanoma A375 cell line and M14 cell line with stable expression of progerin. The expression of progerin, paxillin, and epithelial-mesenchymal transition (EMT) marker proteins in each cell group was measured using Western blot. The migration, proliferation, and cell cycle of cancer cells were assessed using the transwell assay, wound healing assay, colony formation assay, CCK 8 assay, and flow cytometry. RT-qPCR technology was used to examine the impact of progerin overexpression on microRNA expression. Finally, we transfected paxillin into the progerin overexpression cell group to verify whether progerin regulates the phenotype of tumor cells through paxillin. Our study demonstrated that overexpression of progerin leads to decreased expression of paxillin and inhibits cancer cell migration, proliferation, EMT process and cell cycle progression. Additionally, rescue experiments revealed that the migration, proliferation ability, and EMT marker protein expression in progerin overexpressing cancer cells could be partially restored by transfecting a plasmid containing the paxillin gene. Mechanistic investigations further revealed that progerin achieves this inhibition of paxillin expression by upregulating miR-212. This study reveals that progerin may inhibit the migration and proliferation of melanoma cells through the miR-212/paxillin axis, which provides a new approach for the future treatment of this disease.

PXMP4 promotes gastric cancer cell epithelial-mesenchymal transition via the PI3K/AKT signaling pathway.

Peroxisomal membrane protein 4 (PXMP4), a member of the peroxisome membrane protein PXMP2/4 family, participates in the progression of several malignant cancers. Nevertheless, the effect of PXMP4 in the development of gastric cancer (GC) is still unknown. As a result, the focus of this investigation was to elucidate the potential mechanisms of PXMP4 in GC. Firstly, bioinformatics analysis results showed higher expression of PXMP4 in GC tissues. Secondly, clinical analysis of 57 patients with GC revealed correlations between PXMP4 expression and differentiation, depth of invasion, as well as TNM stage. Furthermore, individuals with elevated PXMP4 expression in GC exhibited an unfavorable prognosis. In vitro data showed the involvement of knockdown/overexpression of PXMP4 in the proliferation, invasion, and migration of GC cells, and triggering the epithelial-mesenchymal transition (EMT) of GC cells through the activation of the PI3K/AKT signaling pathway. LY294002, a PI3K/AKT inhibitor, inhibited the expression of PI3K/AKT-related proteins but did not affect the expression of PXMP4. These findings indicate that PXMP4 potentially functions as an upstream molecule in the PI3K/AKT pathway, governing the EMT process in GC.

Overexpression of BZW1 promotes invasion and metastasis of gastric cancer cells by regulating Wnt/β-catenin signaling and promoting epithelial-mesenchymal transition

To investigate the expression level of basic leucine zipper and W2 domain-containing protein 1 (BZW1) in gastric cancer, its impact on patient prognosis and the underlying mechanisms. TIMER, UALCAN and Kaplan-Meier Plotter databases were used for analyzing BZW1 expression level gastric cancer tissues and its correlation with tumor grade and stage and the patients' prognosis. We further analyzed BZW1 expressions, disease progression, and postoperative 5-year survival in 102 patients undergoing radical surgery for gastric cancer at our hospital between January, 2014 and December, 2016. Gastric cancer MGC803 cells were examined for changes in migration, invasion, and epithelial-mesenchymal transition (EMT) following lentivirus-mediated BZW1 overexpression or knockdown. The protein and mRNA expressions of BZW1 in gastric cancer tissues were 3.30 and 6.54 times of those in adjacent tissues, respectively (P < 0.01). BZW1 expression in gastric cancer tissues were positively correlated with peripheral blood CEA and CA199 levels (P < 0.01). A high BZW1 expression was an independent risk factor for 5-year survival of gastric cancer patients after radical surgery (P < 0.05, HR=2.070, 95%CI: 1.021-4.196). At the cut-off value of 3.61, BZW1 expression had a sensitivity of 75.56% and a specificity of 71.93% for predicting postoperative 5-year mortality (P < 0.01). In MGC803 cells, BZW1 overexpression obviously promoted cell migration and invasion (P < 0.05), enhanced cellular expressions of N-cadherin and vimentin (P < 0.05) and inhibited the expression of E-cadherin (P < 0.05). Enrichment analysis suggested the involvement of BZW1 in the Wnt/β-catenin signaling pathway. Western blotting confirmed that BZW1 overexpression promoted while BZW1 knockdown inhibited the expressions of Wnt3a, β-catenin and C-myc in MGC803 cells (P < 0.05). BZW1 is highly expressed in gastric cancer tissues to affect the patient prognosis possibly by activation the Wnt/β-catenin signaling pathway to promote EMT of gastric cancer cells.

RNA-binding protein DND1 participates in migration, invasion, and EMT of prostate cancer cells by degrading CLIC4.

Dead-End 1 (DND1) is an RNA-binding protein (RBP) with regulatory functions in multiple cancers, including gastric and colorectal. Nevertheless, the role that DND1 plays in prostatic cancer (PCa) as well as the hidden molecular mechanism is still obscure. The gene expression of DND1 and survival analyses in PCa were analyzed by the UALCAN database. Expression of DND1 and chloride intracellular channel 4 (CLIC4) were detected by qRT-PCR and western blot analysis. The Cell Counting Kit-8 assay and EDU staining were employed for the estimation of cell viability. The capabilities of cells to migrate and invade were appraised by the wound healing assay as well as the Transwell assay, while epithelial-mesenchymal transition (EMT) was measured by immunofluorescence and western blot assay. The interaction of DND1 and CLIC4 was predicted by PCTA, linkedomics, and RPISeq databases. It was discovered that DND1 expression was elevated in PCa cells. DND1 silencing had suppressive impacts on cells' proliferative, migrative, and invasive capabilities as well as EMT in DU145 and 22Rv1 cells. Mechanistically, bioinformatic analysis demonstrated that DND1 was negatively correlated with CLIC4 and that DND1 protein could bind to CLIC4 mRNA. Additionally, the CLIC4 level was reduced in PCa cells. CLIC4 depletion countervailed the suppressive impacts of DND1 deficiency on the capabilities of DU145 and 22Rv1 cells to proliferate, migrate, and invade as well as the process of EMT. These results suggested that DND1 silencing repressed the proliferation, migration, invasion, and EMT in PCa by regulating the mRNA level of CLIC4.

Diverse temporal and spatial mechanisms work, partially through Stanniocalcin-1, V-ATPase and senescence, to activate the extracellular ATP-mediated drug resistance in human cancer cells.

Resistance to drug therapies is associated with a large majority of cancer-related deaths. ATP-binding cassette (ABC) transporter-mediated drug efflux, epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs), glutathione (GSH), senescence, and vacuole-type ATPase (V-ATPase) all contribute to the resistance. We recently showed that extracellular ATP (eATP) induces and regulates EMT, CSC formation, and ABC transporters in human cancer cells and tumors. eATP also consistently upregulates Stanniocalcin-1 (STC1), a gene that significantly contributes to EMT, CSC formation, and tumor growth. We also found that eATP enhances drug resistance in cancer cells through eATP internalization mediated by macropinocytosis, leading to an elevation of intracellular ATP (iATP) levels, induction of EMT, and CSC formation. However, these factors have never been systematically investigated in the context of eATP-induced drug resistance. In this study, we hypothesized that eATP increases drug resistance via inducing ABC efflux, EMT, CSCs, STC1, and their accompanied processes such as GSH reducing activity, senescence, and V-ATPase. RNA sequencing, metabolomics, gene knockdown and knockout, and functional assays were performed to investigate these pathways and processes. Our study results showed that, in multiple human cancer lines, eATP induced genes involved in drug resistance, elevated ABC transporters' efflux activity of anticancer drugs; generated transcriptomic and metabolic profiles representing a drug resistant state; upregulated activities of GSH, senescence, and V-ATPase to promote drug resistance. Collectively, these newly found players shed light on the mechanisms of eATP-induced as well as STC1- and V-ATPase-mediated drug resistance and offer potential novel targets for combating drug resistance in cancers.