Objective To explore the mechanism of TPT1-AS1 targeting miR-324/TWIST1 axis to regulate the proliferation, invasion, migration and angiogenesis of epithelial ovarian cancer (EOC) cells, thereby affecting ovarian cancer (OC) progression. Methods RT-qPCR was used to detect the expression of TPT1-AS1 and miR-324 in 29 OC lesions and adjacent tissue samples. The two OC cell models of TPT1-AS1 overexpression and miRNA324 knockdown were constructed, and the cell proliferation, invasion and migration abilities were detected by CCK-8, Transwell^TM and scratch test. Western blot analysis was used to detect the protein expression levels of TWIST1, epithelial cadherin (E-cadherin), Vimentin, and vascular endothelial growth factor A (VEGF-A) in OC cells. Fluorescence in situ hybridization (FISH) and RNA pull-down experiments were used to verify the interaction between TPT1-AS1 and miR-324. Immunohistochemistry and Targetscan bioinformatics analysis were used to verify the negative regulatory role of miR-324 in the epithelial-mesenchymal transition (EMT) process. Results The TPT1-AS1 expression was significantly higher in OC tissues than that in para-cancerous tissues, while the miR-324 expression was significantly lower. In SKOV3 cells with TPT1-AS1 overexpression, the miR-324 expression decreased significantly, and TPT1-AS1 was negatively correlated with miR-324. It was also found that TPT1-AS1 and miR-324 were co-expressed in OC cells, and there was a direct binding relationship between them. Down-regulation of miR-324 significantly promoted the proliferation, invasion and migration of SKOV3 cells. Further studies revealed that miR-324 had a binding site at the 3'-UTR end of the TWIST1, a key transcription factor for EMT. Inhibiting miR-324 expression increased the transcription level of TWIST1, leading to a decrease in E-cadherin protein expression and an increase in Vimentin protein expression. Additionally, the downregulation of miR-324 resulted in an increased expression level of VEGF-A protein, which in turn enhanced angiogenesis of OC. Conclusion TPT1-AS1 promotes EOC cell proliferation, invasion, migration and angiogenesis by negatively regulating the miR-324/TWIST1 axis, thus promoting the development of OC. These findings provide new potential targets for the diagnosis and treatment of OC.
Humans ; MicroRNAs/metabolism* ; Female ; Cell Movement/genetics* ; Ovarian Neoplasms/blood supply* ; Twist-Related Protein 1/metabolism* ; Cell Line, Tumor ; Neovascularization, Pathologic/genetics* ; Neoplasm Invasiveness ; Carcinoma, Ovarian Epithelial/metabolism* ; Nuclear Proteins/metabolism* ; Cell Proliferation/genetics* ; Epithelial-Mesenchymal Transition/genetics* ; Gene Expression Regulation, Neoplastic ; RNA, Long Noncoding/metabolism* ; Cadherins/genetics* ; Vascular Endothelial Growth Factor A/genetics* ; Vimentin/genetics* ; Angiogenesis

BACKGROUND: Abnormalities of the switch/sucrose nonfermentable (SWI/SNF) chromatin-remodeling complex are closely related to various cancers, and ARID1B (AT-rich interaction domain 1B) is one of the core subunits of the SWI/SNF complex. Mutations or copy number deletions of the ARID1B gene are associated with impaired DNA damage response and altered chromatin accessibility. However, whether ARID1B deficiency affects the proliferation, migration and invasion abilities of non-small cell lung cancer (NSCLC) cells and its molecular mechanisms remain poorly understood. This study aims to reveal the regulatory role of ARID1B gene deletion on the malignant phenotype of NSCLC cells and its molecular mechanism. METHODS: Online databases were used to analyze the relationship between ARID1B and the prognosis of patients with lung cancer, and the expression levels of ARID1B in lung cancer tissues. The CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat) technology was employed to construct stable ARID1B gene knockout (KO) cell lines. The plate colony formation assay was used to detect cell proliferation, and the Transwell cell migration and invasion assays were used to detect changes in cell migration ability. RNA-Seq was utilized for the expression and enrichment analysis of differentially expressed genes. Western blot (WB) was used to verify the knockout effect of the ARID1B gene and to detect the expression changes of epithelial-mesenchymal transition (EMT) markers and mitogen-activated protein kinases (MAPK) signaling pathway-related proteins. Nude mouse tumor models were constructed and the tumorigenic abilities of control and ARID1B-deficient cells were compared. RESULTS: Patients with low ARID1B expression have poor overall survival. ARID1B is differentially expressed in lung cancer and normal tissues, and its expression level being lower in cancer cells. ARID1B-deficient cells had significantly enhanced in vitro proliferation, migration and invasion abilities. In animal experiments, the tumor formation speed of ARID1B gene deficient cells was significantly accelerated. Enrichment analysis of RNA-Seq results revealed that the differentially expressed genes were mainly enriched in MAPK, phosphoinositide 3-kinase-protein kinase B (PI3K/Akt) and other signaling pathways. WB experiments demonstrated that the expressions of E-cadherin, N-cadherin and Vimentin changed in ARID1B gene deficient cells, and the expressions of MAPK and p-MAPK was increased. CONCLUSIONS The A549-ARID1B KO and PC9-ARID1B KO cell lines were successfully established. The ARID1B-deficient cell lines demonstrated high migration, invasion and proliferation potential at both in vitro and in vivo biological behavior levels and at the transcriptome sequencing level. The changes in the expression of EMT markers and the activation of the MAPK signaling pathway suggest possible metastasis mechanisms of ARID1B-deficient NSCLC.
Humans ; Cell Proliferation/genetics* ; Cell Movement/genetics* ; Lung Neoplasms/metabolism* ; Animals ; Carcinoma, Non-Small-Cell Lung/physiopathology* ; Transcription Factors/metabolism* ; Neoplasm Invasiveness ; Mice ; DNA-Binding Proteins/metabolism* ; Gene Deletion ; Cell Line, Tumor ; Epithelial-Mesenchymal Transition ; Mice, Nude ; Gene Expression Regulation, Neoplastic

OBJECTIVES: Oxaliplatin (OXA) and 5-fluorouracil (5-FU) are 2 commonly used chemotherapeutic agents for colorectal cancer (CRC). MicroRNAs (miRNAs, miRs) play crucial roles in the development of chemoresistance in various cancers. However, the role and mechanism of miR-224-5p in regulating CRC chemoresistance remain unclear. This study aims to investigate the function of miR-224-5p in chemoresistant CRC cells and the underlying mechanisms. METHODS: CRC datasets GSE28702 and GSE69657 were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed miRNAs between drug-sensitive and resistant groups (OXA or 5-FU) were analyzed, and miR-224-5p was identified as the target miRNA. Chemoresistant cell lines HCT15-OXR, HCT15-5-FU, SW480-OXR, and SW480-5-FU were established. Transient transfections were performed using miR-224-5p mimics, inhibitors, and their respective negative controls (control mimic, control inhibitor) in these cell lines. Cells were treated with different concentrations of OXA or 5-FU post-transfection, and the half-maximal inhibitory concentration (IC₅₀) was determined using the cell counting kit-8 (CCK-8) assay. Cell proliferation was assessed by CCK-8 and colony formation assays. The expression levels of miR-224-5p, LC3, and P62 were measured by real-time polymerase chain reaction (real-time PCR) and/or Western blotting. Autophagic flux was assessed using a tandem fluorescent-tagged LC3 reporter assay. TargetScan 8.0, miRTarBase, miRPathDB, and HADb were used to predict B-cell lymphoma-2 (Bcl-2) as a potential miR-244-5p target, which was further validated by dual-luciferase reporter assays. RESULTS: Chemoresistant CRC cells exhibited down-regulated miR-224-5p expression, whereas up-regulation of miR-224-5p enhanced chemotherapy sensitivity. Exposure to OXA or 5-FU significantly increased autophagic activity in chemoresistant CRC cells, which was reversed by miR-224-5p overexpression. Dual-luciferase assays verified Bcl-2 as a direct target of miR-224-5p. CONCLUSIONS MiR-224-5p regulates chemoresistance in CRC by modulating autophagy through direct targeting of Bcl-2.
Humans ; MicroRNAs/physiology* ; Colorectal Neoplasms/drug therapy* ; Drug Resistance, Neoplasm/genetics* ; Autophagy/drug effects* ; Fluorouracil/pharmacology* ; Oxaliplatin ; Cell Line, Tumor ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Gene Expression Regulation, Neoplastic

OBJECTIVES: To investigate the effect of downregulation of medium-chain acyl-coenzyme A dehydrogenase (ACADM) on invasion and migration of estrogen receptor-positive breast cancer cells and the underlying mechanism. METHODS: The Kaplan-Meier Plotter database was used to analyze the ACADM expression levels in breast cancer and normal tissues and their association with patient prognosis. Human breast cancer MCF-7 and T47D cell lines with lentivirus-mediated ACADM knockdown were established, and their in situ tumor formation and metastasis after tail vein injection were evaluated in nude mice. The MCF-7 and T47D cells with ACADM knockdown and their unmodified parental cells were examined with oil-red O staining assay, ROS assay, mitochondrial respiratory chain function assay before and after treatments with ROS scavenger, Elamipretide (a cardiolipin oxidation inhibitor) or SC79 (an AKT activator), and the changes in migration and invasion abilities of the treated cells were analyzed with Transwell invasion assay and Boyden chamber assay. Western blotting was used to detect protein expression levels of related signaling pathways in the treated cells. RESULTS: ACADM overexpression was associated with a significantly shorter overall survival of breast cancer patients. In MCF-7 and T47D cells, ACADM knockdown resulted in downregulation of N calnexin, vimentin, p-P13K and p-AKT proteins, increased levels of free fatty acids and reactive oxygen species, lowered activities of mitochondrial respiratory chain complex III and V, and reduced mitochondrial inner phospholipids. ACADM knockdown significantly decreased the invasive capacity of the cells, which were obviously reversed by treatment with ROS scavenger, Elamipretide, and SC79. CONCLUSIONS Down-regulation of ACADM inhibits migration and invasion ability of estrogen receptor-positive breast cancer cells by lowering lipotoxicity and impairing mitochondrial function through the ROS/PI3K/AKT pathway.
Humans ; Breast Neoplasms/metabolism* ; Female ; Mice, Nude ; Down-Regulation ; Neoplasm Invasiveness ; Animals ; Mice ; Receptors, Estrogen/metabolism* ; MCF-7 Cells ; Cell Movement ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Acyl-CoA Dehydrogenase/genetics* ; Signal Transduction ; Neoplasm Metastasis ; Proto-Oncogene Proteins c-akt/metabolism*

OBJECTIVES: To study the effect of CDC20 knockdown on proliferation, migration and invasion of cervical cancer cells and its underlying mechanism. METHODS: CDC20 expression in cervical cancer tissues was analyzed using the TCGA database, and the protein expressions of CDC20 and β-Catenin in clinical specimens of cervical cancer and adjacent tissues were detected using immunohistochemistry. A dual target sgRNA2&7 sequence for CDC20 gene was designed for CDC20 gene knockdown in cervical cancer C33A cells using CRISPR/Cas9 technology, and CDC20 mRNA and protein expression levels in the transfected cells were detected using qRT-PCR and Western blotting. The changes in proliferation, cell cycle, apoptosis, migration and invasiveness of the transfected cells were evaluated using colony-forming assay, fluorescence activated cell sorting (FACS) and Transwell assay. In the animal experiment, naïve C33A cells and the cells with CDC20 knockdown were injected subcutaneously into the left and right axillae of nude mice (n=5) to observe tumor growth. The expressions of CDC20 and β-Catenin proteins in transfected cells and the xenograft were analyzed using Western blotting, and their interaction was confirmed by co-immunoprecipitation (CoIP) and immunofluorescence co-localization assays. RESULTS: Cervical cancer tissues expressed significantly higher CDC20 and β‑Catenin levels than the adjacent tissues. C33A cells with CDC20 knockdown showed reduced proliferation, increased apoptosis, and lowered migration and invasion abilities. CDC20 knockdown significantly suppressed the growth of C33A cell xenograft in nude mice, and the tumor-bearing mice did not exhibit obvious body mass changes. CDC20 and β-Catenin levels were both significantly lowered in C33A cells with CDC20 knockdown. Co-immunoprecipitation and co-localization assays confirmed the interaction between CDC20 and β‑Catenin. CONCLUSIONS CDC20 is highly expressed in cervical cancer tissues, and CDC20 knockdown can suppress proliferation, invasion, and metastasis while enhancing apoptosis of C33A cells, which is closely related with the regulation of the Wnt/β-Catenin signaling pathway.
Humans ; Uterine Cervical Neoplasms/metabolism* ; Female ; Cdc20 Proteins/genetics* ; Cell Proliferation ; Animals ; Cell Movement ; Neoplasm Invasiveness ; Apoptosis ; Mice, Nude ; beta Catenin/metabolism* ; CRISPR-Cas Systems ; Mice ; Cell Line, Tumor ; Gene Knockout Techniques ; Neoplasm Metastasis

Hypoxia and aberrant activation of epidermal growth factor receptor (EGFR) are considered important features of various malignancies. However, whether hypoxia can directly trigger EGFR activation and its clinical implications remain unclear. In this study, we demonstrated that in oral cancer, a typical hypoxic tumor, hypoxia can induce chronic but constitutive phosphorylation of wild-type EGFR in the absence of ligands. Oral cancer cell lines exhibit different EGFR phosphorylation responses to hypoxia. In hypoxic HN4 and HN6 cells, ubiquitination-mediated endocytosis, lysosomal sorting, and degradation lead to low levels of EGFR phosphorylation. However, in CAL-27 and HN30 cells, a novel HIF-1α-induced long noncoding RNA (lncRNA), EUDAL, can compete with the E3 ligase/adaptor complex c-Cbl/Grb2 for binding to EGFR, stabilizing phosphorylated EGFR (pEGFR) and resulting in sustained activation of EGFR and its downstream STAT3/BNIP3 signaling. STAT3/BNIP3-mediated autophagy leads to antitumor drug resistance. A high EUDAL/EGFR/STAT3/autophagy pathway activation predicts poor response to chemotherapy in oral cancer patients. Collectively, hypoxia can induce noncanonical ligand-independent EGFR phosphorylation. High EUDAL expression facilitates sustained EGFR phosphorylation in hypoxic tumor cells and leads to autophagy-related drug resistance.
Humans ; ErbB Receptors/metabolism* ; Mouth Neoplasms/pathology* ; RNA, Long Noncoding/genetics* ; Drug Resistance, Neoplasm/genetics* ; Cell Line, Tumor ; Phosphorylation ; Signal Transduction ; STAT3 Transcription Factor/metabolism* ; Cell Hypoxia ; Autophagy ; Proto-Oncogene Proteins c-cbl/metabolism*

The transcription factor HOXB13 plays crucial roles in cancer development. HOXB13 is abnormally expressed in most cancers, which makes it a valuable therapeutic target for cancer therapy. The level of HOXB13 differs significantly between healthy and cancer tissues, which indicates that the level of HOXB13 is closely related to carcinogenesis. The regulatory network mediated by HOXB13 in cancer proliferation, metastasis, and invasion has been systematically investigated. Moreover, HOXB13 variants play distinct roles in different cancers and populations. By understanding the molecular mechanisms and mutation features of HOXB13, we provide a comprehensive overview of carcinogenesis networks dependent on HOXB13. Finally, we discuss advancements in anticancer therapy targeting HOXB13 and the roles of HOXB13 in drug resistance to molecular-targeted therapies, which serves as a foundation for developing HOXB13-targeted drugs for clinical diagnosis and cancer therapies.
Humans ; Neoplasms/metabolism* ; Homeodomain Proteins/metabolism* ; Carcinogenesis/genetics* ; Mutation ; Gene Expression Regulation, Neoplastic ; Molecular Targeted Therapy ; Drug Resistance, Neoplasm/genetics*

OBJECTIVES: This study aimed to explore the expression of lysosomal-associated membrane protein 5 (LAMP5) and microRNA (miR)-302a-3p in oral squamous cell carcinoma (OSCC) and their functional mechanism on the invasion and metastasis of OSCC. METHODS: The expression of LAMP5 in OSCC and its sensitivity as a prognostic indicator were analyzed on the basis of The Cancer Genome Atlas database. Western blot, quantitative reverse transcription polymerase chain reaction, and cell immunocytochemistry were used to detect the expression of LAMP5 in OSCC tissues and cells. The effect of LAMP5 on the proliferation, migration, and invasion of OSCC cells was evaluated through cell counting kit-8, immunocytochemistry, migration, and invasion assays, respectively. The miRNA targeting prediction websites were used to predict the miR that regulates LAMP5 and verify the targeted regulatory effect of miR-302a-3p on LAMP5. The effect of LAMP5 knockdown on OSCC tumor growth was evaluated in a nude mouse tumorigenesis model. RESULTS: LAMP5 was highly expressed in OSCC tissues and cells. It showed high sensitivity in the early diagnosis of OSCC. LAMP5 knockdown significantly inhibited the proliferation, migration, and invasion of OSCC cells, whereas LAMP5 overexpression increased these cell activities. The expression of LAMP5 was regulated by miR-302a-3p. In vivo, LAMP5 knockdown significantly inhibited the growth of OSCC tumor. CONCLUSIONS LAMP5 promotes the malignant progression of OSCC by enhancing the proliferation, migration, and invasion of OSCC cells. The expression of LAMP5 is negatively regulated by miR-302a-3p.
MicroRNAs/metabolism* ; Mouth Neoplasms/metabolism* ; Humans ; Animals ; Carcinoma, Squamous Cell/genetics* ; Neoplasm Invasiveness ; Cell Proliferation ; Mice, Nude ; Cell Movement ; Lysosomal Membrane Proteins/genetics* ; Mice ; Cell Line, Tumor ; Neoplasm Metastasis

BACKGROUND: Enzalutamide, a second-generation androgen receptor (AR) pathway inhibitor, is widely used in the treatment of castration-resistant prostate cancer. However, after a period of enzalutamide treatment, patients inevitably develop drug resistance. In this study, we characterized leucine-rich repeated G-protein-coupled receptor 5 (LGR5) and explored its potential therapeutic value in prostate cancer. METHODS: A total of 142 pairs of tumor and adjacent formalin-fixed paraf-fin-embedded tissue samples from patients with prostate cancer were collected from the Pathology Department at Sun Yat-sen Memorial Hos-pital. LGR5 was screened by sequencing data of enzalutamide-resistant cell lines combined with sequencing data of lesions with different Gleason scores from the same patients. The biological function of LGR5 and its effect on enzalutamide resistance were investigated in vitro and in vivo . Glutathione-S-transferase (GST) pull-down, coimmunoprecipitation, Western blotting, and immunofluorescence assays were used to explore the specific binding mechanism of LGR5 and related pathway changes. RESULTS: LGR5 was significantly upregulated in prostate cancer and negatively correlated with poor patient prognosis. Overexpression of LGR5 promoted the malignant progression of prostate cancer and reduced sensitivity to enzalutamide in vitro and in vivo . LGR5 promoted the phosphorylation of glycogen synthase kinase-3β (GSK-3β) by binding heat shock protein 90,000 alpha B1 (HSP90AB1) and mediated the activation of the Wingless/integrated (WNT)/β-catenin signaling pathway. The increased β-catenin in the cytoplasm entered the nucleus and bound to the nuclear AR, promoting the transcription level of AR, which led to the enhanced tolerance of prostate cancer to enzalutamide. Reducing HSP90AB1 binding to LGR5 significantly enhanced sensitivity to enzalutamide. CONCLUSIONS LGR5 directly binds to HSP90AB1 and mediates GSK-3β phosphorylation, promoting AR expression by regulating the WNT/β-catenin signaling pathway, thereby conferring resistance to enzalutamide treatment in prostate cancer.
Male ; Humans ; Phenylthiohydantoin/pharmacology* ; Benzamides ; Receptors, G-Protein-Coupled/genetics* ; Nitriles ; Cell Line, Tumor ; HSP90 Heat-Shock Proteins/metabolism* ; Drug Resistance, Neoplasm/genetics* ; Prostatic Neoplasms/drug therapy* ; beta Catenin/metabolism* ; Receptors, Androgen/genetics* ; Animals ; Mice ; Wnt Signaling Pathway/physiology*

BACKGROUND: Temozolomide (TMZ) resistance is a significant challenge in treating glioblastoma (GBM). Collagen remodeling has been shown to be a critical factor for therapy resistance in other cancers. This study aimed to investigate the mechanism of TMZ chemoresistance by GBM cells reprogramming collagens. METHODS: Key extracellular matrix components, including collagens, were examined in paired primary and recurrent GBM samples as well as in TMZ-treated spontaneous and grafted GBM murine models. Human GBM cell lines (U251, TS667) and mouse primary GBM cells were used for in vitro studies. RNA-sequencing analysis, chromatin immunoprecipitation, immunoprecipitation-mass spectrometry, and co-immunoprecipitation assays were conducted to explore the mechanisms involved in collagen accumulation. A series of in vitro and in vivo experiments were designed to assess the role of the collagen regulators prolyl 4-hydroxylase subunit alpha 1 (P4HA1) and yes-associated protein (YAP) in sensitizing GBM cells to TMZ. RESULTS: This study revealed that TMZ exposure significantly elevated collagen type I (COL I) expression in both GBM patients and murine models. Collagen accumulation sustained GBM cell survival under TMZ-induced stress, contributing to enhanced TMZ resistance. Mechanistically, P4HA1 directly binded to and hydroxylated YAP, preventing ubiquitination-mediated YAP degradation. Stabilized YAP robustly drove collagen type I alpha 1 ( COL1A1) transcription, leading to increased collagen deposition. Disruption of the P4HA1-YAP axis effectively reduced COL I deposition, sensitized GBM cells to TMZ, and significantly improved mouse survival. CONCLUSION P4HA1 maintained YAP-mediated COL1A1 transcription, leading to collagen accumulation and promoting chemoresistance in GBM.
Temozolomide ; Humans ; Glioblastoma/drug therapy* ; Animals ; Mice ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; YAP-Signaling Proteins ; Hydroxylation ; Dacarbazine/pharmacology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Transcription Factors/metabolism* ; Collagen/biosynthesis* ; Collagen Type I/metabolism* ; Prolyl Hydroxylases/metabolism* ; Antineoplastic Agents, Alkylating/therapeutic use*