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Embryo implantation is a tightly regulated process, critical for a successful pregnancy. After attachment of the blastocyst to the surface epithelium of the endometrium trophoblast migrate from the trophectoderm and invade into the stromal component of endometrium. Alterations on either process will lead to implantation failure or miscarriage. Volatile organic compounds (VOCs) such as benzene induce pregnancy complications, including preterm birth and miscarriages. The mechanism of this effect is unknown. The objective of this study was to elucidate the impact of benzene metabolite, Hydroquinone, on trophoblast function. We tested the hypothesis that Hydroquinone activates the Aryl hydrocarbon receptor (AhR) pathway modulating trophoblast migration and invasion. First-trimester trophoblast cells (Sw.71) were treated with hydroquinone (6 and 25 μM). Trophoblast migration and invasion was evaluated using a 3D invasion/migration model. Gene expression was quantified by q-PCR and Western blot analysis. Hydroquinone impairs trophoblast migration and invasion. This loss is associated with the activation of the AhR pathway which reduced the expression of Twist1and IFITM1. IFITM1 overexpression can rescue impaired trophoblast migration. Our study highlights that hydroquinone treatment induces the activation of the AhR pathway in trophoblast cells, which impairs trophoblast invasion and migration. We postulate that activation of the AhR pathway in trophoblast suppress Twist1 and a subsequent IFITM1. Thus, the AhR-Twist1-IFITM1 axis represent a critical pathway involved in the regulation of trophoblast migration and it is sensitive to benzene exposure. These findings provide crucial insights into the molecular mechanisms underlying pregnancy complications induced by air pollution. [Display omitted] • Benzene exposure affects pregnancy outcome. • Hydroquinone treatment inhibits trophoblast migration and invasion. • The AhR pathway is functional in trophoblast cells. • Hydroquinone activates the Ahr pathway in trophoblast. • Twist1 and IFITM1 are major regulators of trophoblast migration. [ABSTRACT FROM AUTHOR]

The regeneration of peripheral nerves after injury is often slow and impaired, which may be associated with weakened and denervated muscles subsequently leading to atrophy. Adipose-derived stem cells (ADSCs) are often regarded as cell-based therapeutic candidate due to their regenerative potential. The study aims to assess the therapeutic efficacy of gene-modified ADSCs on sciatic nerve injury. We lentivirally transduced ADSCs with shRNA-TWIST1 and transplanted modified cells to rats undergoing sciatic nerve transection and repair. Results showed that TWIST1 knockdown accelerated functional recovery of rats with sciatic nerve injury as faster nerve conduction velocity and higher wire hang scores obtained by rats transplanted with TWIST1-silenced ADSCs than scramble ADSCs. Although the rats experienced degenerated axons and decreased myelin sheath thickness after sciatic nerve injury 8 weeks after operation, those transplanted with TWIST1-silenced ADSCs exhibited more signs of regenerated nerve fibers surrounded by newly formed myelin sheaths than those with scramble ADSCs. The rats transplanted with TWIST1-silenced ADSCs presented increased expressions of neurotrophic factors including neurotrophin-3 (NT-3), brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and glial cell line-derived neurotrophic factor (GDNF) in the sciatic nerves than those with scramble ADSCs. These results suggest that genetically modifying TWIST1 in ADSCs could facilitate peripheral nerve repair after injury in a more efficient way than that with ADSCs alone. [ABSTRACT FROM AUTHOR]

BACKGROUND: The dura mater and skull are physically and functionally related, although there have been few investigations on primary extraction of dura mater and cranial cells, as well as co-culture of the two. The use of primary cells to investigate the influence of the dura mater on the skull is novel, and it is hoped that it may give a theoretical foundation for therapeutic therapy. OBJECTIVE: Rat dura mater and cranial bone cells were retrieved in situ to observe the influence of dura mater on cranial bone proliferation and differentiation, as well as to get a basic knowledge of the involvement of Twist1 in this process. METHODS: The enzyme digestion method was used in conjunction with the tissue block method to extract dural cells and cranial osteoblasts from rats within three days of birth. Immunofluorescence staining was used to identify the extracted cells, and alizarin red staining was used to identify and evaluate cranial osteoblasts and their mineralization ability. After co-culturing dural cells and cranial osteoblasts, real-time PCR was utilized to identify the expression of genes associated to cranial osteoblast proliferation and osteogenesis, as well as Twist1. RESULTS AND CONCLUSION: (1) Morphology: The retrieved dural cells had morphological traits similar to fibroblasts, while the osteoblasts were spindle-shaped. (2) Cell identification: immunofluorescence staining revealed that extracted dural cells expressed high levels of vimentin and cranial osteoblasts expressed high levels of alkaline phosphatase; cranial osteoblasts were stained with alizarin red 28 days after osteogenic induction, and obvious mineralized nodules were observed. (3) Real time PCR detection showed that the co-culture group had higher levels of PCNA, alkaline phosphatase, and RUNX2 mRNA expression than the control group (P < 0.01); however, Twist1 mRNA expression was lower (P < 0.01). (4) The findings showed that the primary extracted cranial osteoblasts had a high mineralization capacity, and that the dura mater was a key factor in promoting cranial growth and development and osteogenic differentiation, with Twist1 playing a key role in this process. [ABSTRACT FROM AUTHOR]

RNA N6‐methyladenosine (m6A) readers mediate cancer progression. However, the functional role and potential mechanisms of the m6A readers in prostate cancer tumorigenicity remain to be elucidated. In this study, we demonstrate that YTHDF3 expression is elevated in castration‐resistant prostate cancer (CRPC) and positively correlated to high grade, bone metastasis and poor survival. YTHDF3 expression promoted CRPC cell proliferation, epithelial to mesenchymal transition (EMT) and tumour progression. Mechanistically, YTHDF3 promoted the RNA degradation of SPOP and NXK3.1 but stabilized RNA expressions of TWIST1 and SNAI2 dependent on m6A to facilitate cell proliferation and EMT. Additionally, YTHDF3 expression enhanced AKT activity via degrading SPOP in an m6A‐dependent manner. Importantly, we found that melatonin can compete with m6A to occupy the m6A‐binding cage of YTHDF3, leading to inhibition of YTHFD3 and its target expressions as well as CRPC tumour growth. Our findings uncover an essential role of YTHDF3 in the progression of CRPC and highlight the role of melatonin in anti‐CRPC activity. [ABSTRACT FROM AUTHOR]

Simple Summary: TWIST1 is a transcription factor that induces epithelial-mesenchymal transition (EMT), and EMT is positively associated with programmed death ligand 1 (PD-L1) expression and immune escape in breast cancer cells. However, the relationship between TWIST1 and PD-L1 or immune evasion in breast cancer is unknown. In this study, we found that PD-L1 is a target gene of TWIST1. TWIST1 interacts with the TIP60 acetyltransferase complex in a BRD8-dependent manner to robustly upregulate PD-L1 expression. The knockdown of TWIST1 or BRD8 largely diminished PD-L1 expression and enhanced the CD8+ T-cell-mediated inhibition of breast cancer cell growth. Furthermore, the blockade of PD-L1 expressed in TWIST1-positive breast cancer cells also abolished the TWIST1-mediated suppression of CD8+ T cells and reinvigorated CD8+ T cells to inhibit cancer cells. These results suggest that TWIST1 may be a potential target for silencing PD-L1 expression to prevent the exhaustion of cytotoxic CD8+ T cells. In breast cancer, epithelial-mesenchymal transition (EMT) is positively associated with programmed death ligand 1 (PD-L1) expression and immune escape, and TWIST1 silences ERα expression and induces EMT and cancer metastasis. However, how TWIST1 regulates PD-L1 and immune evasion is unknown. This study analyzed TWIST1 and PD-L1 expression in breast cancers, investigated the mechanism for TWIST1 to regulate PD-L1 transcription, and assessed the effects of TWIST1 and PD-L1 in cancer cells on cytotoxic CD8+ T cells. Interestingly, TWIST1 expression is correlated with high-level PD-L1 expression in ERα-negative breast cancer cells. The overexpression and knockdown of TWIST1 robustly upregulate and downregulate PD-L1 expression, respectively. TWIST1 binds to the PD-L1 promoter and recruits the TIP60 acetyltransferase complex in a BRD8-dependent manner to transcriptionally activate PD-L1 expression, which significantly accelerates the exhaustion and death of the cytotoxic CD8+ T cells. Accordingly, knockdown of TWIST1 or BRD8 or inhibition of PD-L1 significantly enhances the tumor antigen-specific CD8+ T cells to suppress the growth of breast cancer cells. These results demonstrate that TWIST1 directly induces PD-L1 expression in ERα-negative breast cancer cells to promote immune evasion. Targeting TWIST1, BRD8, and/or PD-L1 in ERα-negative breast cancer cells with TWIST1 expression may sensitize CD8+ T-cell-mediated immunotherapy. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this research was to elucidate the role of miR-34b in cervical cancer progression and the underlying mechanism behind the miR-34b-mediated tumor suppression. The study revealed the role of miR-34b as a senescence inducer and serves as a potential therapeutic target in developing combination therapy with senotherapeutics. Methods: MiR-34b was ectopically expressed in cervical cancer cell lines using a tetracycline inducible system and its effects on cell viability, apoptosis, senescence, DNA damage and oxidative stress were studied using MTT assay, acridine orange/ ethidium bromide staining, senescence associated β-galactosidase assay, gamma H2AX foci staining assay, western blotting and specific dyes for the detection of total and individual ROS species. Results: Ectopic expression of miR-34b promoted cellular senescence but no significant induction of apoptosis was observed in cervical cancer cell lines. MiR-34b promoted increase in oxidative stress through increase in total and individual ROS species and contributed to increase in cellular senescence. Mechanistically, miR-34b mediates its action by targeting TWIST1 as evidenced by the similar actions of TWIST1 shRNA in cervical cancer cell lines. Furthermore, our study revealed TWIST1 is one of the most significant targets of miR-34b targetome and identified RITA as a novel senolytic agent for use in combination therapy with miR-34b. Conclusion: MiR-34b promotes cellular senescence and oxidative stress by targeting TWIST1, a known oncogene and EMT regulator. This study delved into the mechanism of miR-34b-mediated tumor suppression and provided novel insights for development of miR-34b based therapeutics for cervical cancer.

Abstract MicroRNAs are small RNA molecules that have a significant role in translational repression and gene silencing through binding to downstream target mRNAs. MiR-762 can stimulate the proliferation and metastasis of various types of cancer. Hippo pathway is one of the pathways that regulate tissue development and carcinogenesis. Dysregulation of this pathway plays a vital role in the progression of cancer. This study aimed to evaluate the possible correlation between miR-762, the Hippo signaling pathway, TWIST1, and SMAD3 in patients with lung cancer, as well as patients with chronic inflammatory diseases. The relative expression of miR-762, MST1, LATS2, YAP, TWIST1, and SMAD3 was determined in 50 lung cancer patients, 30 patients with chronic inflammatory diseases, and 20 healthy volunteers by real-time PCR. The levels of YAP protein and neuron-specific enolase were estimated by ELISA and electrochemiluminescence immunoassay, respectively. Compared to the control group, miR-762, YAP, TWIST1, and SMAD3 expression were significantly upregulated in lung cancer patients and chronic inflammatory patients, except SMAD3 was significantly downregulated in chronic inflammatory patients. MST1, LATS2, and YAP protein were significantly downregulated in all patients. MiR-762 has a significant negative correlation with MST1, LATS2, and YAP protein in lung cancer patients and with MST1 and LATS2 in chronic inflammatory patients. MiR-762 may be involved in the induction of malignant behaviors in lung cancer through suppression of the Hippo pathway. MiR-762, MST1, LATS2, YAP mRNA and protein, TWIST1, and SMAD3 may be effective diagnostic biomarkers in both lung cancer patients and chronic inflammatory patients. High YAP, TWIST1, SMA3 expression, and NSE level are associated with a favorable prognosis for lung cancer.

TWIST1 (TW) is a pro‐oncogenic basic helix–loop–helix (bHLH) transcription factor and promotes the hallmark features of malignancy (e.g., cell invasion, cancer cell stemness, and treatment resistance), which contribute to poor prognoses of glioblastoma (GBM). We previously reported that specific TW dimerization motifs regulate unique cellular phenotypes in GBM. For example, the TW:E12 heterodimer increases periostin (POSTN) expression and promotes cell invasion. TW dimer‐specific transcriptional regulation requires binding to the regulatory E‐box consensus sequences, but alternative bHLH dimers that balance TW dimer activity in regulating pro‐oncogenic TW target genes are unknown. We leveraged the ENCODE DNase I hypersensitivity data to identify E‐box sites and tethered TW:E12 and TW:TW proteins to validate dimer binding to E‐boxes in vitro. Subsequently, TW knockdown revealed a novel TCF4:TCF12 bHLH dimer occupying the same TW E‐box site that, when expressed as a tethered TCF4:TCF12 dimer, markedly repressed POSTN expression and extended animal survival. These observations support TCF4:TCF12 as a novel dimer with tumor‐suppressor activity in GBM that functions in part through displacement of and/or competitive inhibition of pro‐oncogenic TW dimers at E‐box sites.

Introduction: Radiation‐induced pulmonary fibrosis (RIPF) is a chronic, progressive, irreversible lung interstitial disease that develops after radiotherapy. Although several previous studies have focused on the mechanism of epithelial–mesenchymal transition (EMT) in lung epithelial cells, the essential factors involved in this process remain poorly understood. The DNA‐dependent protein kinase catalytic subunit (DNA‐PKcs) exhibits strong repair capacity when cells undergo radiation‐induced damage; whether DNA‐PKcs regulates EMT during RIPF remains unclear. Objectives: To investigate the role and molecular mechanism of DNA‐PKcs in RIPF and provide an important theoretical basis for utilising DNA‐PKcs‐targeted drugs for preventing RIPF. Methods: DNA‐PKcs knockout (DPK−/−) mice were generated via the Cas9/sgRNA technique and subjected to whole chest ionizing radiation (IR) at a 20 Gy dose. Before whole chest IR, the mice were intragastrically administered the DNA‐PKcs‐targeted drug VND3207. Lung tissues were collected at 1 and 5 months after IR. Results: The expression of DNA‐PKcs is low in pulmonary fibrosis (PF) patients. DNA‐PKcs deficiency significantly exacerbated RIPF by promoting EMT in lung epithelial cells. Mechanistically, DNA‐PKcs deletion by shRNA or inhibitor NU7441 maintained the protein stability of Twist1. Furthermore, AKT1 mediated the interaction between DNA‐PKcs and Twist1. High Twist1 expression and EMT‐associated changes caused by DNA‐PKcs deletion were blocked by insulin‐like growth factor‐1 (IGF‐1), an AKT1 agonist. The radioprotective drug VND3207 prevented IR‐induced EMT and alleviated RIPF in mice by stimulating the kinase activity of DNA‐PKcs. Conclusion: Our study clarified the critical role and mechanism of DNA‐PKcs in RIPF and showed that it could be a potential target for preventing RIPF. [ABSTRACT FROM AUTHOR]

Background: Synovial sarcoma (SS) is an SS18‐SSX fusion gene‐driven soft tissue sarcoma with mesenchymal characteristics, associated with a poor prognosis due to frequent metastasis to a distant organ, such as the lung. Histone deacetylase (HDAC) inhibitors (HDACis) are arising as potent molecular targeted drugs, as HDACi treatment disrupts the SS oncoprotein complex, which includes HDACs, in addition to general HDACi effects. To provide further molecular evidence for the advantages of HDACi treatment and its limitations due to drug resistance induced by the microenvironment in SS cells, we examined cellular responses to HDACi treatment in combination with two‐dimensional (2D) and 3D culture conditions. Methods: Using several SS cell lines, biochemical and cell biological assays were performed with romidepsin, an HDAC1/2 selective inhibitor. SN38 was concomitantly used as an ameliorant drug with romidepsin treatment. Cytostasis, apoptosis induction, and MHC class I polypeptide‐related sequence A/B (MICA/B) induction were monitored to evaluate the drug efficacy. In addition to the conventional 2D culture condition, spheroid culture was adopted to evaluate the influence of cell‐mass microenvironment on chemoresistance. Results: By monitoring the cellular behavior with romidepsin and/or SN38 in SS cells, we observed that responsiveness is diverse in each cell line. In the apoptotic inducible cells, co‐treatment with SN38 enhanced cell death. In nonapoptotic inducible cells, cytostasis and MICA/B induction were observed, and SN38 improved MICA/B induction further. As a novel efficacy of SN38, we revealed TWIST1 suppression in SS cells. In the spheroid (3D) condition, romidepsin efficacy was severely restricted in TWIST1‐positive cells. We demonstrated that TWIST1 downregulation restored romidepsin efficacy even in spheroid form, and concomitant SN38 treatment along with romidepsin reproduced the reaction. Conclusions: The current study demonstrated the benefits and concerns of using HDACi for SS treatment in 2D and 3D culture conditions and provided molecular evidence that concomitant treatment with SN38 can overcome drug resistance to HDACi by suppressing TWIST1 expression. [ABSTRACT FROM AUTHOR]

Background: Ulcerative colitis (UC) is a common and progressive inflammatory bowel disease primarily affecting the colon and rectum. Prolonged inflammation can lead to colitis-associated colorectal cancer (CAC). While the exact cause of UC remains unknown, this study aims to investigate the role of the TWIST1 gene in UC. Methods: Second-generation sequencing data from adult UC patients were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified, and characteristic genes were selected using machine learning and Lasso regression. The Receiver Operating Characteristic (ROC) curve assessed TWIST1’s potential as a diagnostic factor (AUC score). Enriched pathways were analyzed, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Variation Analysis (GSVA). Functional mechanisms of marker genes were predicted, considering immune cell infiltration and the competing endogenous RNA (ceRNA) network. Results: We found 530 DEGs, with 341 upregulated and 189 downregulated genes. TWIST1 emerged as one of four potential UC biomarkers via machine learning. TWIST1 expression significantly differed in two datasets, GSE193677 and GSE83687, suggesting its diagnostic potential (AUC = 0.717 in GSE193677, AUC = 0.897 in GSE83687). Enrichment analysis indicated DEGs associated with TWIST1 were involved in processes like leukocyte migration, humoral immune response, and cell chemotaxis. Immune cell infiltration analysis revealed higher rates of M0 macrophages and resting NK cells in the high TWIST1 expression group, while TWIST1 expression correlated positively with M2 macrophages and resting NK cell infiltration. We constructed a ceRNA regulatory network involving 1 mRNA, 7 miRNAs, and 32 long non-coding RNAs (lncRNAs) to explore TWIST1’s regulatory mechanism. Conclusion: TWIST1 plays a significant role in UC and has potential as a diagnostic marker. This study sheds light on UC’s molecular mechanisms and underscores TWIST1’s importance in its progression. Further research is needed to validate these findings in diverse populations and investigate TWIST1 as a therapeutic target in UC. [ABSTRACT FROM AUTHOR]

In this study, an oil-in-water (o/w) nanoemulsion is used to deliver siRNA targeting Twist1, a protein that contributes to tumor metastasis in a variety of cancers. The FDA-approved oil, medium chain triglycerides (MCT), is used as the hydrophobic phase for the nanoemulsion. The siRNA is paired with dioleoyl-3-trimethylammonium-propane (DOTAP) to form a hydrophobic salt that is soluble at high concentrations in MCT. The resulting MCT/siRNA-DOTAP solution is formulated into a nanoemulsion with an average particle size of 140 nm. The nanoemulsion displays long term stability over the course of 195 days. In an in vivo murine tumor model, the nanoemulsion facilitates a 46% decrease in Twist1 mRNA after 48 h. [ABSTRACT FROM AUTHOR]

Background: Diagnosis of early mycosis fungoides (eMF) is challenging and often delayed as many of its clinical and histopathologic features may mimic various benign inflammatory dermatoses (BIDs). The products of the thymocyte selection‐associated high mobility group box (TOX), twist family BHLH transcription factor 1 (TWIST1), signal transducer and activator of transcription 4 (STAT4), and special AT‐rich sequence‐binding protein 1 (SATB1) genes function as transcription factors and are involved in the pathogenesis of MF. Objectives: We aim to determine the diagnostic value of TOX, TWIST1, STAT4, and SATB1 protein expressions in eMF. Methods: This non‐randomized, controlled, prospective analytic study was conducted by performing immunohistochemistry staining with TOX, TWIST1, STAT4, and SATB1 polyclonal antibodies in lesional skin biopsies of eMF and BID patients. Nuclear staining of lymphocytes was compared between eMF and BIDs, and the capacity of these antibodies to predict eMF was determined. Results: Immunostainings with anti‐TWIST1 showed an increase in protein expression (p = 0.003) and showed a decrease with anti‐SATB1 antibodies in eMF compared to BIDs (p = 0.005) while anti‐TOX and anti‐STAT4 antibodies did not exhibit significant differences (p = 0.384; p = 0.150). Receiver operating characteristic analysis showed that immunohistochemical evaluations of TWIST1 and SATB1 protein expressions can differentiate eMF (area under the curve [AUC]: 0.728, 95% confidence interval [CI]: 0.605–0.851, p = 0.002; AUC: 0.686, 95% CI: 0.565–0.807, p = 0.013). Conclusions: TWIST1 and SATB1 are potential diagnostic markers for the histologic diagnosis of eMF. [ABSTRACT FROM AUTHOR]

TWIST1 (TW) is a pro‐oncogenic basic helix–loop–helix (bHLH) transcription factor and promotes the hallmark features of malignancy (e.g., cell invasion, cancer cell stemness, and treatment resistance), which contribute to poor prognoses of glioblastoma (GBM). We previously reported that specific TW dimerization motifs regulate unique cellular phenotypes in GBM. For example, the TW:E12 heterodimer increases periostin (POSTN) expression and promotes cell invasion. TW dimer‐specific transcriptional regulation requires binding to the regulatory E‐box consensus sequences, but alternative bHLH dimers that balance TW dimer activity in regulating pro‐oncogenic TW target genes are unknown. We leveraged the ENCODE DNase I hypersensitivity data to identify E‐box sites and tethered TW:E12 and TW:TW proteins to validate dimer binding to E‐boxes in vitro. Subsequently, TW knockdown revealed a novel TCF4:TCF12 bHLH dimer occupying the same TW E‐box site that, when expressed as a tethered TCF4:TCF12 dimer, markedly repressed POSTN expression and extended animal survival. These observations support TCF4:TCF12 as a novel dimer with tumor‐suppressor activity in GBM that functions in part through displacement of and/or competitive inhibition of pro‐oncogenic TW dimers at E‐box sites. [ABSTRACT FROM AUTHOR]

Anaplastic thyroid carcinoma (ATC) is an extremely difficult disease to tackle, with an overall patient survival of only a few months. The currently used therapeutic drugs, such as kinase inhibitors or immune checkpoint inhibitors, can prolong patient survival but fail to eradicate the tumor. In addition, the onset of drug resistance and adverse side-effects over time drastically reduce the chances of treatment. We recently showed that Twist1, a transcription factor involved in the epithelial mesenchymal transition (EMT), was strongly upregulated in ATC, and we wondered whether it might represent a therapeutic target in ATC patients. To investigate this hypothesis, the effects of harmine, a β-carboline alkaloid shown to induce degradation of the Twist1 protein and to possess antitumoral activity in different cancer types, were evaluated on two ATC-derived cell lines, BHT-101 and CAL-62. The results obtained demonstrated that, in both cell lines, harmine reduced the level of Twist1 protein and reverted the EMT, as suggested by the augmentation of E-cadherin and decrease in fibronectin expression. The drug also inhibited cell proliferation and migration in a dose-dependent manner and significantly reduced the anchorage-independent growth of both ATC cell lines. Harmine was also capable of inducing apoptosis in BHT-101 cells, but not in CAL-62 ones. Finally, the activation of PI3K/Akt signaling, but not that of the MAPK, was drastically reduced in treated cells. Overall, these in vitro data suggest that harmine could represent a new therapeutic option for ATC treatment. [ABSTRACT FROM AUTHOR]

TWIST1 is a transcription factor that is necessary for healthy neural crest migration, mesoderm development, and gastrulation. It functions as a key regulator of epithelial-to-mesenchymal transition (EMT), a process by which cells lose their polarity and gain the ability to migrate. EMT is often reactivated in cancers, where it is strongly associated with tumor cell invasion and metastasis. Early work on TWIST1 in adult tissues focused on its transcriptional targets and how EMT gave rise to metastatic cells. In recent years, the roles of TWIST1 and other EMT factors in cancer have expanded greatly as our understanding of tumor progression has advanced. TWIST1 and related factors are frequently tied to cancer cell stemness and changes in therapeutic responses and thus are now being viewed as attractive therapeutic targets. In this review, we highlight non-metastatic roles for TWIST1 and related EMT factors in cancer and other disorders, discuss recent findings in the areas of therapeutic resistance and stemness in cancer, and comment on the potential to target EMT for therapy. Further research into EMT will inform novel treatment combinations and strategies for advanced cancers and other diseases. [ABSTRACT FROM AUTHOR]

In recent years, lung cancer has become one of the most common malignant tumors in the world, which seriously threatens the life and health of mankind. Lung cancer is also the most common cancer in China. According to the latest report released by the National Cancer Center, the incidence and fatality rate of lung cancer in China rank first among malignant tumors, which has brought great disease burden to the Chinese. In this paper, using ethyl acetoacetate as the starting material, eight benzo[d]imidazolium[2,1-b]thiazole target compounds containing chromone were synthesized in five steps through alpha halogenation, cyclization, hydrolysis, condensation and cyclization reaction. MTT assay was used to evaluate the in vitro inhibitory activity of the target compounds on A549 and H2228 cancer cells. The IC50 values of the target compounds to A549 and H2228 cell lines ranged from 17.63 to 369.09 μmol/L. Some target compounds have moderate anti-tumor activity in vitro, which could be used to prepare related anti-tumor drugs for lung cancer. [ABSTRACT FROM AUTHOR]

Currently, radiotherapy is one of the most attractive treatments for prostate cancer (PCa) patients. However, radioresistance remains a challenging issue and the underlying mechanism is unknown. Growing evidence has demonstrated that CDC20 (Cell division cycle protein 20) plays a pivotal role in a variety of tumors, including PCa. Here, GEPIA database mining and western blot analysis showed that higher expression of CDC20 was observed in PCa tissues and cells. We demonstrated that the expression of CDC20 was increased in PCa cells by irradiation, and knockdown of CDC20 resulted in inhibition of cell proliferation, migration, tumor formation, induced cell apoptosis and increased radiosensitivity in PCa in vitro and in vivo. Furthermore, we observed that CDC20 regulated Twist1 pathway, influencing cell proliferation and migration. These results suggest that targeting CDC20 and Twist1 may be an effective way to improve the radiosensitivity of PCa. [ABSTRACT FROM AUTHOR]

Despite extensive clinical testing, mesenchymal stem/stromal cell (MSC)-based therapies continue to underperform with respect to efficacy, which reflects the paucity of biomarkers that predict potency prior to patient administration. Previously, we reported that TWIST1 predicts inter-donor differences in MSC quality attributes that confer potency. To define the full spectrum of TWIST1 activity in MSCs, the present work employed integrated omics-based profiling to identify a high-confidence set of TWIST1 targets, which mapped to cellular processes related to ECM structure/organization, skeletal and circulatory system development, interferon gamma signaling, and inflammation. These targets are implicated in contributing to both stem/progenitor and paracrine activities of MSCs indicating these processes are linked mechanistically in a TWIST1-dependent manner. Targets implicated in extracellular matrix dynamics further implicate TWIST1 in modulating cellular responses to niche remodeling. Novel TWIST1-regulated genes identified herein may be prioritized for future mechanistic and functional studies. Graphical Abstract [ABSTRACT FROM AUTHOR]

Abstract Introduction Radiation‐induced pulmonary fibrosis (RIPF) is a chronic, progressive, irreversible lung interstitial disease that develops after radiotherapy. Although several previous studies have focused on the mechanism of epithelial–mesenchymal transition (EMT) in lung epithelial cells, the essential factors involved in this process remain poorly understood. The DNA‐dependent protein kinase catalytic subunit (DNA‐PKcs) exhibits strong repair capacity when cells undergo radiation‐induced damage; whether DNA‐PKcs regulates EMT during RIPF remains unclear. Objectives To investigate the role and molecular mechanism of DNA‐PKcs in RIPF and provide an important theoretical basis for utilising DNA‐PKcs‐targeted drugs for preventing RIPF. Methods DNA‐PKcs knockout (DPK−/−) mice were generated via the Cas9/sgRNA technique and subjected to whole chest ionizing radiation (IR) at a 20 Gy dose. Before whole chest IR, the mice were intragastrically administered the DNA‐PKcs‐targeted drug VND3207. Lung tissues were collected at 1 and 5 months after IR. Results The expression of DNA‐PKcs is low in pulmonary fibrosis (PF) patients. DNA‐PKcs deficiency significantly exacerbated RIPF by promoting EMT in lung epithelial cells. Mechanistically, DNA‐PKcs deletion by shRNA or inhibitor NU7441 maintained the protein stability of Twist1. Furthermore, AKT1 mediated the interaction between DNA‐PKcs and Twist1. High Twist1 expression and EMT‐associated changes caused by DNA‐PKcs deletion were blocked by insulin‐like growth factor‐1 (IGF‐1), an AKT1 agonist. The radioprotective drug VND3207 prevented IR‐induced EMT and alleviated RIPF in mice by stimulating the kinase activity of DNA‐PKcs. Conclusion Our study clarified the critical role and mechanism of DNA‐PKcs in RIPF and showed that it could be a potential target for preventing RIPF.

Abstract The abnormal lipid and glucose metabolisms are linked to the metabolic disorders, tumorigenesis, and fibrotic diseases, which attracts the increasing attention to find out the key molecules involved in the lipid and glucose metabolism as the possible therapeutic targets on these diseases. A transcriptional factor Twist1 has been associated with not only the embryonic development, cancer, and fibrotic diseases, but also the regulation of lipid and glucose metabolism. In this review, we will discuss the roles and mechanisms of Twist1 in the obesity-associated white adipose tissue inflammation and insulin resistance, brown adipose tissue metabolism, fatty acid oxidation, and glucose metabolism in skeletal muscle to provide a rational perspective to consider Twist1 as a potential treatment target in clinic. Video Abstract

Abstract Chemoresistance poses a significant impediment to effective treatment strategies for myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Our previous study unveiled that oncogene TWIST1 interacted with DNA methyltransferase 3a (DNMT3a) to regulate the decitabine (DAC) resistance in MDS/AML. However, the underlying mechanism of TWIST1 dysregulation in DAC resistance remained enigmatic. Here, we found that O-GlcNAc modification was upregulated in CD34+ cells from MDS/AML patients who do not respond to DAC treatment. Functional study revealed that O-GlcNAcylation could stabilize TWIST1 by impeding its interaction with ubiquitin E3 ligase CBLC. In addition, as one typical transcription factor, TWIST1 could bind to the promoter of O-GlcNAc transferase (OGT) gene and activate its transcription. Collectively, we highlighted the crucial role of the O-GlcNAcylated TWIST1 in the chemoresistance capacity of MDS/AML clonal cells, which may pave the way for the development of a new therapeutic strategy targeting O-GlcNAcylated proteins and reducing the ratio of MDS/AML relapse. Video Abstract

Abstract Background Overexpression of Twist1, one of the epithelial-mesenchymal transition-transcription factors (EMT-TFs), is associated with hepatocellular carcinoma (HCC) metastasis. Pelitinib is known to be an irreversible epidermal growth factor receptor tyrosine kinase inhibitor that is used in clinical trials for colorectal and lung cancers, but the role of pelitinib in cancer metastasis has not been studied. This study aimed to investigate the anti-migration and anti-invasion activities of pelitinib in HCC cell lines. Methods Using three HCC cell lines (Huh7, Hep3B, and SNU449 cells), the effects of pelitinib on cell cytotoxicity, invasion, and migration were determined by cell viability, wound healing, transwell invasion, and spheroid invasion assays. The activities of MMP-2 and -9 were examined through gelatin zymography. Through immunoblotting analyses, the expression levels of EMT-TFs (Snail1, Twist1, and ZEB1) and EMT-related signaling pathways such as mitogen-activated protein kinases (MAPKs) and Akt signaling pathways were measured. The activity and expression levels of target genes were analyzed by reporter assay, RT-PCR, quantitative RT-PCR, and immunoblotting analysis. Statistical analysis was performed using one-way ANOVA with Dunnett's Multiple comparison tests in Prism 3.0 to assess differences between experimental conditions. Results In this study, pelitinib treatment significantly inhibited wound closure in various HCC cell lines, including Huh7, Hep3B, and SNU449. Additionally, pelitinib was found to inhibit multicellular cancer spheroid invasion and metalloprotease activities in Huh7 cells. Further investigation revealed that pelitinib treatment inhibited the migration and invasion of Huh7 cells by inducing Twist1 degradation through the inhibition of MAPK and Akt signaling pathways. We also confirmed that the inhibition of cell motility by Twist1 siRNA was similar to that observed in pelitinib-treated group. Furthermore, pelitinib treatment regulated the expression of target genes associated with EMT, as demonstrated by the upregulation of E-cadherin and downregulation of N-cadherin. Conclusion Based on our novel finding of pelitinib from the perspective of EMT, pelitinib has the ability to inhibit EMT activity of HCC cells via inhibition of Twist1, and this may be the potential mechanism of pelitinib on the suppression of migration and invasion of HCC cells. Therefore, pelitinib could be developed as a potential anti-cancer drug for HCC.

Abstract Background Prostate cancer remains one of the deadliest neoplasms in developed countries. Identification of new molecular markers that predict the onset and progression of the disease could improve its clinical management. Low miR-145-5p expression is consistently found in primary tumors and metastases, but the regulatory mechanisms governing its functions remain largely unknown. Methods Bioinformatics analysis was conducted to identify [1] a set of novel potential competing endogenous lncRNAs for sponging of miRNA-145-5p in prostate cancer and [2] miR-145-5p and other EMT-related miRNAs response elements in lnc-ZNF30-3. Quantification of miR-145-5p, lnc-ZNF30-3, and TWIST1 expression levels in tumor tissues in RNA sequencing datasets of our and TCGA PRAD cohorts revealed a correlation with clinical outcome of prostate cancer patients. Biochemical and cell biology approaches, such as RNA pull-down, western blot, immunostaining, and wound healing assays were used for evaluation of the impact of TWIST1/miR-145/ lnc-ZNF30-3 interactions in prostate cancer cells altered in miRNA and lncRNA expression. Results We identified a few potential lncRNA sponges of miR-145-5p, including lnc-ZNF30-3. It contains five response elements for miR-145-5p, but also other miRNAs targeting EMT transcription factors. Lnc-ZNF30-3 is significantly upregulated in prostate cancer cell lines and tumor tissues, and its high expression is correlated with poor patient prognosis. We demonstrated that lnc-ZNF30-3 is associated with AGO2 and specifically interacts with the miR-145-5p seed region. Knockdown of lnc-ZNF30-3 results in decreased migration of prostate cancer cells and downregulation of EMT drivers such as TWIST1 and ZEB1 at both the RNA and protein levels. These phenotypic and molecular features of lnc-ZNF30-3-depleted cells are partially rescued by miR-145-5p inhibition. Conclusions Collectively, our results point to lnc-ZNF30-3 as a novel competing endogenous lncRNA for miR-145-5p and other miRNAs that target TWIST1 as well as other EMT transcription factors. Prostate cancer patients with high lncRNA expression in primary tumors show lower survival rate suggesting that lnc-ZNF30-3 may contribute to prostate cancer progression and metastasis.

Abstract Background USP51 is a deubiquitinase (DUB), that is involved in diverse cellular processes. Accumulating evidence has demonstrated that USP51 contributes to cancer development. However, its impact on non-small cell lung carcinoma (NSCLC) cell malignancy is largely unknown. Methods In this study, we performed bioinformatics analysis on a dataset from The Cancer Genome Atlas to determine the association between USP51 and cell stemness marker expression in NSCLC patients. RT‒qPCR, Western blotting, and flow cytometry were performed to examine the effects of USP51 depletion on stemness marker expression. Colony formation and tumor sphere formation assays were used to assess the stemness of NSCLC cells. A cycloheximide chase time-course assay and a polyubiquitination assay were carried out to analyze the effects of USP51 on the TWIST1 protein level. TWIST1 was overexpressed in USP51 knockdown NSCLC cells to determine whether TWIST1 is required. The effect of USP51 on the in vivo growth of NSCLC cells was tested through subcutaneous injections in mice. Results We found that USP51 deubiquitinates TWIST1, which is significantly upregulated in the tissues of patients with NSCLC and is closely associated with poor prognosis. USP51 expression was positively correlated with the expression of stemness marker CD44, SOX2, NANOG, and OCT4 in NSCLC patients. USP51 depletion attenuated mRNA, protein, and cell surface expression of stemness markers and the stemness of NSCLC cells. Ectopic USP51 expression potentiated the stability of the TWIST1 protein by attenuating its polyubiquitination. In addition, TWIST1 re-expression in NSCLC cells reversed the inhibitory effect of USP51 knockdown on cell stemness. Furthermore, the in vivo results confirmed the suppressive effect of USP51 depletion on NSCLC cell growth. Conclusions Our results show that USP51 maintains the stemness of NSCLC cells by deubiquitinating TWIST1. Knocking it down reduces both cell stemness and growth of NSCLC cells.

Abstract Background Salivary carcinoma ex pleomorphic adenoma (CXPA) is defined as a carcinoma that develops from benign pleomorphic adenoma (PA). Abnormally activated Androgen signaling pathway and amplification of HER-2/neu(ERBB-2) gene are known to be involved in CXPA tumorigenesis. Recent progress in tumour microenvironment research has led to identification that extracellular matrix (ECM) remodelling and increased stiffness act as critical contributing role in tumour carcinogenesis. This study examined ECM modifications to elucidate the mechanism underlying CXPA tumorigenesis. Results PA and CXPA organoids were successfully established. Histological observation, immunohistochemistry (IHC), and whole-exome sequencing demonstrated that organoids recapitulated phenotypic and molecular characteristics of their parental tumours. RNA-sequencing and bioinformatic analysis of organoids showed that differentially expressed genes are highly enriched in ECM-associated terms, implying that ECM alternations may be involved in carcinogenesis. Microscopical examination for surgical samples revealed that excessive hyalinized tissues were deposited in tumour during CXPA tumorigenesis. Transmission electron microscopy confirmed that these hyalinized tissues were tumour ECM in nature. Subsequently, examination by picrosirius red staining, liquid chromatography with tandem mass spectrometry, and cross-linking analysis indicated that tumour ECM was predominantly composed of type I collagen fibers, with dense collagen alignment and an increased level of collagen cross-linking. IHC revealed the overexpression of COL1A1 protein and collagen-synthesis-related genes, DCN and IGFBP5 (p

Simple Summary: Esophageal squamous cell carcinoma (ESCC) is a malignancy characterized by high mortality and dismal quality of life. Circulating tumor cells (CTCs), considered precursors of distant metastasis, can be analyzed using a non-invasive liquid biopsy approach to identify patients at risk of cancer progression or recurrence. The current study employed an unbiased size-based CTC enrichment strategy in combination with quantitative reverse transcription polymerase chain reaction (RT-qPCR) to investigate gene transcripts as potential biomarkers in the bloodstream. We categorized 83.6% (46/55) of ESCC patients as CTC-positive, each displaying at least two detected markers. Furthermore, 50.9% (28/55) of ESCC patients were identified as CTC-high, showing at least five detected markers using a 10-gene CTC panel. The presence of specific markers, namely TWIST1, VEGFC, CCND1, and TFRC, was significantly associated with shorter survival of the patients, suggesting their prognostic values as liquid biopsy markers to guide clinical ESCC treatment decisions and enhance treatment efficacy. We investigated the clinical significance of CTCs in cancer progression by detecting multiple cancer driver genes associated with epithelial-to-mesenchymal transition (EMT) at the transcript level. The 10-gene panel, comprising CCND1, ECT2, EpCAM, FSCN1, KRT5, KRT18, MET, TFRC, TWIST1, and VEGFC, was established for characterizing CTCs from mouse ESCC xenograft models and clinical ESCC peripheral blood (PB) samples. Correlations between gene expression in CTCs from PB samples (n = 77) and clinicopathological features in ESCC patients (n = 55) were examined. The presence of CTCs at baseline was significantly correlated with tumor size (p = 0.031). The CTC-high patients were significantly correlated with advanced cancer stages (p = 0.013) and distant metastasis (p = 0.029). High mRNA levels of TWIST1 (Hazard Ratio (HR) = 5.44, p = 0.007), VEGFC (HR = 6.67, p < 0.001), TFRC (HR = 2.63, p = 0.034), and EpCAM (HR = 2.53, p = 0.041) at baseline were significantly associated with a shorter overall survival (OS) in ESCC patients. This study also revealed that TWIST1 facilitates EMT and enhances malignant potential by promoting tumor migration, invasion, and cisplatin chemoresistance through the TWIST1-TGFBI-ZEB1 axis in ESCC, highlighting the prognostic and therapeutic potential of TWIST1 in clinical ESCC treatment. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly improved progression-free survival in hormone-receptor-positive (HR+), human-epidermal-growth-factor-receptor-type-2-negative (HER2−) metastatic luminal breast cancer (mLBC). Several studies have shown that in patients with endocrine-sensitive or endocrine-resistant LBC, the addition of CDK4/6 inhibitors to endocrine therapy significantly prolongs progression-free survival. However, the percentage of patients who are unresponsive or refractory to these therapies is as high as 40%, and no reliable and reproducible biomarkers have been validated to select a priori responders or refractory patients. The selection of mutant clones in the target oncoprotein is the main cause of resistance. Other mechanisms such as oncogene amplification/overexpression or mutations in other pathways have been described in several models. In this study, we focused on palbociclib, a selective CDK4/6 inhibitor. We generated a human MCF-7 luminal breast cancer cell line that was able to survive and proliferate at different concentrations of palbociclib and also showed cross-resistance to abemaciclib. The resistant cell line was characterized via RNA sequencing and was found to strongly activate the epithelial-to-mesenchymal transition. Among the top deregulated genes, we found a dramatic downregulation of the CDK4 inhibitor CDKN2B and an upregulation of the TWIST1 transcription factor. TWIST1 was further validated as a target for the reversal of palbociclib resistance. This study provides new relevant information about the mechanisms of resistance to CDK4/6 inhibitors and suggests potential new markers for patients' follow-up care during treatment. [ABSTRACT FROM AUTHOR]

TWIST1 induces epithelial‐to‐mesenchymal transition (EMT) to drive cancer metastasis. It is yet unclear what determines TWIST1 functions to activate or repress transcription. We found that the TWIST1 N‐terminus antagonizes TWIST1‐regulated gene expression, cancer growth and metastasis. TWIST1 interacts with both the NuRD complex and the NuA4/TIP60 complex (TIP60‐Com) via its N‐terminus. Non‐acetylated TWIST1‐K73/76 selectively interacts with and recruits NuRD to repress epithelial target gene transcription. Diacetylated TWIST1‐acK73/76 binds BRD8, a component of TIP60‐Com that also binds histone H4‐acK5/8, to recruit TIP60‐Com to activate mesenchymal target genes and MYC. Knockdown of BRD8 abolishes TWIST1 and TIP60‐Com interaction and TIP60‐Com recruitment to TWIST1‐activated genes, resulting in decreasing TWIST1‐activated target gene expression and cancer metastasis. Both TWIST1/NuRD and TWIST1/TIP60‐Com complexes are required for TWIST1 to promote EMT, proliferation, and metastasis at full capacity. Therefore, the diacetylation status of TWIST1‐K73/76 dictates whether TWIST1 interacts either with NuRD to repress epithelial genes, or with TIP60‐Com to activate mesenchymal genes and MYC. Since BRD8 is essential for TWIST1‐acK73/76 and TIP60‐Com interaction, targeting BRD8 could be a means to inhibit TWIST1‐activated gene expression. Synopsis: Non‐acetylated TWIST1 induces EMT and metastasis by interacting with the NuRD complex to repress epithelial genes. Diacetylated TWIST1 interacts with BRD8 in the NuA4/TIP60 complex to activate MYC and mesenchymal genes. TWIST1 has a non‐acetylated and a diacetylated form, which interacts with the NuRD and the TIP60 complex, respectively.TWIST1–NuRD represses epithelial target genes. TWIST1‐acK73/K76–TIP60 activates mesenchymal target genes.TWIST1 requires both of these transcriptional activities to fully induce breast cancer cell growth, EMT and metastasis.TWIST1‐N competes with TWIST1 for TIP60 and NuRD binding, thereby inhibiting TWIST1‐induced EMT and metastasis. [ABSTRACT FROM AUTHOR]

The abnormal lipid and glucose metabolisms are linked to the metabolic disorders, tumorigenesis, and fibrotic diseases, which attracts the increasing attention to find out the key molecules involved in the lipid and glucose metabolism as the possible therapeutic targets on these diseases. A transcriptional factor Twist1 has been associated with not only the embryonic development, cancer, and fibrotic diseases, but also the regulation of lipid and glucose metabolism. In this review, we will discuss the roles and mechanisms of Twist1 in the obesity-associated white adipose tissue inflammation and insulin resistance, brown adipose tissue metabolism, fatty acid oxidation, and glucose metabolism in skeletal muscle to provide a rational perspective to consider Twist1 as a potential treatment target in clinic. Epq8RQY38Fsn9qua6D8Y77 Video Abstract [ABSTRACT FROM AUTHOR]

Chemoresistance poses a significant impediment to effective treatment strategies for myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Our previous study unveiled that oncogene TWIST1 interacted with DNA methyltransferase 3a (DNMT3a) to regulate the decitabine (DAC) resistance in MDS/AML. However, the underlying mechanism of TWIST1 dysregulation in DAC resistance remained enigmatic. Here, we found that O-GlcNAc modification was upregulated in CD34+ cells from MDS/AML patients who do not respond to DAC treatment. Functional study revealed that O-GlcNAcylation could stabilize TWIST1 by impeding its interaction with ubiquitin E3 ligase CBLC. In addition, as one typical transcription factor, TWIST1 could bind to the promoter of O-GlcNAc transferase (OGT) gene and activate its transcription. Collectively, we highlighted the crucial role of the O-GlcNAcylated TWIST1 in the chemoresistance capacity of MDS/AML clonal cells, which may pave the way for the development of a new therapeutic strategy targeting O-GlcNAcylated proteins and reducing the ratio of MDS/AML relapse. E9uGgDrfuE6fB_NeMXiTgk Video Abstract [ABSTRACT FROM AUTHOR]

Secondary lissencephaly evolved in mice due to effects on neurogenesis and the tangential distribution of neurons. Signaling pathways that help maintain lissencephaly are still poorly understood. We show that inactivating Twist1 in the primitive meninges causes cortical folding in mice. Cell proliferation in the meninges is reduced, causing loss of arachnoid fibroblasts that express Raldh2, an enzyme required for retinoic acid synthesis. Regionalized loss of Raldh2 in the dorsolateral meninges is first detected when folding begins. The ventricular zone expands and the forebrain lengthens at this time due to expansion of apical radial glia. As the cortex expands, regionalized differences in the levels of neurogenesis are coupled with changes to the tangential distribution of neurons. Consequentially, cortical growth at and adjacent to the midline accelerates with respect to more dorsolateral regions, resulting in cortical buckling and folding. Maternal retinoic acid supplementation suppresses cortical folding by normalizing forebrain length, neurogenesis and the tangential distribution of neurons. These results suggest that Twist1 and balanced retinoic acid signaling from the meninges are required to maintain normal levels of neurogenesis and lissencephaly in mice. [ABSTRACT FROM AUTHOR]

Bone marrow-derived mesenchymal stem cells (BMMSCs) derived from myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) patients often show a shift in the balance between osteoblastogenesis and adipogenesis. It was suggested that BMMSCs can potentially undergo reprogramming or educational processes. However, the results of reprogrammed differentiation have been inconclusive. In this study, clinical samples, co-culture models and mouse models were employed to explore the association of MDS/AML clonal cells and BMMSCs differentiation. We found that clonal MDS/AML cells promoted adipogenic differentiation and inhibited osteogenic differentiation of BMMSCs, which in turn promoted MDS expansion. Mass spectrometry and cytokine array were used to identify the molecules to drive the BMMSCs differentiation in MDS/AML. Mechanistically, highly expressed transcription factor TWIST1 in clonal MDS/AML cells induces MDS/AML cells to secrete more IFN-γ, which can induce oxidative stress through STAT1-dependent manner, ultimately causing enhanced adipogenic differentiation and inhibited osteogenic differentiation in BMMSCs. Overall, our findings suggest that targeting the driving oncogenes in malignant clonal cells, such as TWIST1, may offer new therapeutic strategies by remodeling the surrounding bone marrow microenvironment in the treatment of MDS/AML and other hematopoietic malignancies.

ING1 is a chromatin targeting subunit of the Sin3a histone deacetylase (HDAC) complex that alters chromatin structure to subsequently regulate gene expression. We find that ING1 knockdown increases expression of Twist1, Zeb 1&2, Snai1, Bmi1 and TSHZ1 drivers of EMT, promoting EMT and cell motility. ING1 expression had the opposite effect, promoting epithelial cell morphology and inhibiting basal and TGF-β-induced motility in 3D organoid cultures. ING1 binds the Twist1 promoter and Twist1 was largely responsible for the ability of ING1 to reduce cell migration. Consistent with ING1 inhibiting Twist1 expression in vivo, an inverse relationship between ING1 and Twist1 levels was seen in breast cancer samples from The Cancer Genome Atlas (TCGA). The HDAC inhibitor vorinostat is approved for treatment of multiple myeloma and cutaneous T cell lymphoma and is in clinical trials for solid tumours as adjuvant therapy. One molecular target of vorinostat is INhibitor of Growth 2 (ING2), that together with ING1 serve as targeting subunits of the Sin3a HDAC complex. Treatment with sublethal (LD25-LD50) levels of vorinostat promoted breast cancer cell migration several-fold, which increased further upon ING1 knockout. These observations indicate that correct targeting of the Sin3a HDAC complex, and HDAC activity in general decreases luminal and basal breast cancer cell motility, suggesting that use of HDAC inhibitors as adjuvant therapies in breast cancers that are prone to metastasize may not be optimal and requires further investigation.

TWIST1 is a basic helix-loop-helix (bHLH) transcription factor in humans that functions in mesoderm differentiation. TWIST1 primarily regulates genes as a transcriptional repressor often through TWIST-Box domain-mediated protein-protein interactions. The TWIST-Box also can function as an activation domain requiring 3 conserved, equidistant amino acids (LXXXFXXXR). Autosomal dominant mutations in TWIST1, including 2 reported in these conserved amino acids (F187L and R191M), lead to craniofacial defects in Saethre-Chotzen syndrome (SCS). Caenorhabditis elegans has a single TWIST1 homolog, HLH-8, that functions in the differentiation of the muscles responsible for egg laying and defecation. Null alleles in hlh-8 lead to severely egg-laying defective and constipated animals due to defects in the corresponding muscles. TWIST1 and HLH-8 share sequence identity in their bHLH regions; however, the domain responsible for the transcriptional activity of HLH-8 is unknown. Sequence alignment suggests that HLH-8 has a TWIST-Box LXXXFXXXR motif; however, its function also is unknown. CRISPR/Cas9 genome editing was utilized to generate a domain deletion and several missense mutations, including those analogous to SCS patients, in the 3 conserved HLH-8 amino acids to investigate their functional role. The TWIST-Box alleles did not phenocopy hlh-8 null mutants. The strongest phenotype detected was a retentive (Ret) phenotype with late-stage embryos in the hermaphrodite uterus. Further, GFP reporters of HLH-8 downstream target genes (arg-1::gfp and egl-15::gfp) revealed tissue-specific, target-specific, and allele-specific defects. Overall, the TWIST-Box in HLH-8 is partially required for the protein's transcriptional activity, and the conserved amino acids contribute unequally to the domain's function. [ABSTRACT FROM AUTHOR]

Claudin-4, a member of the claudin multigene family, participates in events associated with mesenchymal-like activity of cancerous cells. Claudin-4 expression is upregulated in cervical cancer tissue compared with that in adjoining non-neoplastic tissue. However, the mechanisms that regulate Claudin-4 expression in cervical cancer are poorly understood. Moreover, whether Claudin-4 contributes to the migration and invasion of cervical cancer cells remains unclear. By western blotting, reverse transcription-qPCR, bioinformatics analysis, dual-luciferase reporter assay, chromatin immunoprecipitation assay, wound healing assay and Transwell migration/invasion assay, the present study confirmed that Claudin-4 was a downstream target of Twist1, a helix-loop-helix transcriptional factor, the activity of which has a positive correlation with Claudin-4 expression. Mechanistically, Twist1 directly binds to Claudin-4 promoter, resulting in the transactivation of expression. The depletion of the Twist1-binding E-Box1 domain on Claudin-4 promoter via CRISPR-Cas9 knockout system downregulates Claudin-4 expression and suppresses the ability of cervical cancer cells to migrate and invade by elevating E-cadherin levels and lowering N-cadherin levels. Following activation by transforming growth factor-ß, Twist1 induces Claudin-4 expression, thus enhancing migration and invasion of cervical cancer cells. In summary, the present data suggested that Claudin-4 was a direct downstream target of Twist1 and served a critical role in promoting Twist1-mediated cervical cancer cell migration and invasion. [ABSTRACT FROM AUTHOR]

Background: Overexpression of Twist1, one of the epithelial-mesenchymal transition-transcription factors (EMT-TFs), is associated with hepatocellular carcinoma (HCC) metastasis. Pelitinib is known to be an irreversible epidermal growth factor receptor tyrosine kinase inhibitor that is used in clinical trials for colorectal and lung cancers, but the role of pelitinib in cancer metastasis has not been studied. This study aimed to investigate the anti-migration and anti-invasion activities of pelitinib in HCC cell lines. Methods: Using three HCC cell lines (Huh7, Hep3B, and SNU449 cells), the effects of pelitinib on cell cytotoxicity, invasion, and migration were determined by cell viability, wound healing, transwell invasion, and spheroid invasion assays. The activities of MMP-2 and -9 were examined through gelatin zymography. Through immunoblotting analyses, the expression levels of EMT-TFs (Snail1, Twist1, and ZEB1) and EMT-related signaling pathways such as mitogen-activated protein kinases (MAPKs) and Akt signaling pathways were measured. The activity and expression levels of target genes were analyzed by reporter assay, RT-PCR, quantitative RT-PCR, and immunoblotting analysis. Statistical analysis was performed using one-way ANOVA with Dunnett's Multiple comparison tests in Prism 3.0 to assess differences between experimental conditions. Results: In this study, pelitinib treatment significantly inhibited wound closure in various HCC cell lines, including Huh7, Hep3B, and SNU449. Additionally, pelitinib was found to inhibit multicellular cancer spheroid invasion and metalloprotease activities in Huh7 cells. Further investigation revealed that pelitinib treatment inhibited the migration and invasion of Huh7 cells by inducing Twist1 degradation through the inhibition of MAPK and Akt signaling pathways. We also confirmed that the inhibition of cell motility by Twist1 siRNA was similar to that observed in pelitinib-treated group. Furthermore, pelitinib treatment regulated the expression of target genes associated with EMT, as demonstrated by the upregulation of E-cadherin and downregulation of N-cadherin. Conclusion: Based on our novel finding of pelitinib from the perspective of EMT, pelitinib has the ability to inhibit EMT activity of HCC cells via inhibition of Twist1, and this may be the potential mechanism of pelitinib on the suppression of migration and invasion of HCC cells. Therefore, pelitinib could be developed as a potential anti-cancer drug for HCC. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer remains one of the deadliest neoplasms in developed countries. Identification of new molecular markers that predict the onset and progression of the disease could improve its clinical management. Low miR-145-5p expression is consistently found in primary tumors and metastases, but the regulatory mechanisms governing its functions remain largely unknown. Methods: Bioinformatics analysis was conducted to identify [1] a set of novel potential competing endogenous lncRNAs for sponging of miRNA-145-5p in prostate cancer and [2] miR-145-5p and other EMT-related miRNAs response elements in lnc-ZNF30-3. Quantification of miR-145-5p, lnc-ZNF30-3, and TWIST1 expression levels in tumor tissues in RNA sequencing datasets of our and TCGA PRAD cohorts revealed a correlation with clinical outcome of prostate cancer patients. Biochemical and cell biology approaches, such as RNA pull-down, western blot, immunostaining, and wound healing assays were used for evaluation of the impact of TWIST1/miR-145/ lnc-ZNF30-3 interactions in prostate cancer cells altered in miRNA and lncRNA expression. Results: We identified a few potential lncRNA sponges of miR-145-5p, including lnc-ZNF30-3. It contains five response elements for miR-145-5p, but also other miRNAs targeting EMT transcription factors. Lnc-ZNF30-3 is significantly upregulated in prostate cancer cell lines and tumor tissues, and its high expression is correlated with poor patient prognosis. We demonstrated that lnc-ZNF30-3 is associated with AGO2 and specifically interacts with the miR-145-5p seed region. Knockdown of lnc-ZNF30-3 results in decreased migration of prostate cancer cells and downregulation of EMT drivers such as TWIST1 and ZEB1 at both the RNA and protein levels. These phenotypic and molecular features of lnc-ZNF30-3-depleted cells are partially rescued by miR-145-5p inhibition. Conclusions: Collectively, our results point to lnc-ZNF30-3 as a novel competing endogenous lncRNA for miR-145-5p and other miRNAs that target TWIST1 as well as other EMT transcription factors. Prostate cancer patients with high lncRNA expression in primary tumors show lower survival rate suggesting that lnc-ZNF30-3 may contribute to prostate cancer progression and metastasis. [ABSTRACT FROM AUTHOR]

Background: USP51 is a deubiquitinase (DUB), that is involved in diverse cellular processes. Accumulating evidence has demonstrated that USP51 contributes to cancer development. However, its impact on non-small cell lung carcinoma (NSCLC) cell malignancy is largely unknown. Methods: In this study, we performed bioinformatics analysis on a dataset from The Cancer Genome Atlas to determine the association between USP51 and cell stemness marker expression in NSCLC patients. RT‒qPCR, Western blotting, and flow cytometry were performed to examine the effects of USP51 depletion on stemness marker expression. Colony formation and tumor sphere formation assays were used to assess the stemness of NSCLC cells. A cycloheximide chase time-course assay and a polyubiquitination assay were carried out to analyze the effects of USP51 on the TWIST1 protein level. TWIST1 was overexpressed in USP51 knockdown NSCLC cells to determine whether TWIST1 is required. The effect of USP51 on the in vivo growth of NSCLC cells was tested through subcutaneous injections in mice. Results: We found that USP51 deubiquitinates TWIST1, which is significantly upregulated in the tissues of patients with NSCLC and is closely associated with poor prognosis. USP51 expression was positively correlated with the expression of stemness marker CD44, SOX2, NANOG, and OCT4 in NSCLC patients. USP51 depletion attenuated mRNA, protein, and cell surface expression of stemness markers and the stemness of NSCLC cells. Ectopic USP51 expression potentiated the stability of the TWIST1 protein by attenuating its polyubiquitination. In addition, TWIST1 re-expression in NSCLC cells reversed the inhibitory effect of USP51 knockdown on cell stemness. Furthermore, the in vivo results confirmed the suppressive effect of USP51 depletion on NSCLC cell growth. Conclusions: Our results show that USP51 maintains the stemness of NSCLC cells by deubiquitinating TWIST1. Knocking it down reduces both cell stemness and growth of NSCLC cells. [ABSTRACT FROM AUTHOR]

Background: Salivary carcinoma ex pleomorphic adenoma (CXPA) is defined as a carcinoma that develops from benign pleomorphic adenoma (PA). Abnormally activated Androgen signaling pathway and amplification of HER-2/neu(ERBB-2) gene are known to be involved in CXPA tumorigenesis. Recent progress in tumour microenvironment research has led to identification that extracellular matrix (ECM) remodelling and increased stiffness act as critical contributing role in tumour carcinogenesis. This study examined ECM modifications to elucidate the mechanism underlying CXPA tumorigenesis. Results: PA and CXPA organoids were successfully established. Histological observation, immunohistochemistry (IHC), and whole-exome sequencing demonstrated that organoids recapitulated phenotypic and molecular characteristics of their parental tumours. RNA-sequencing and bioinformatic analysis of organoids showed that differentially expressed genes are highly enriched in ECM-associated terms, implying that ECM alternations may be involved in carcinogenesis. Microscopical examination for surgical samples revealed that excessive hyalinized tissues were deposited in tumour during CXPA tumorigenesis. Transmission electron microscopy confirmed that these hyalinized tissues were tumour ECM in nature. Subsequently, examination by picrosirius red staining, liquid chromatography with tandem mass spectrometry, and cross-linking analysis indicated that tumour ECM was predominantly composed of type I collagen fibers, with dense collagen alignment and an increased level of collagen cross-linking. IHC revealed the overexpression of COL1A1 protein and collagen-synthesis-related genes, DCN and IGFBP5 (p < 0.05). Higher stiffness of CXPA than PA was demonstrated by atomic force microscopy and elastic imaging analysis. We utilized hydrogels to mimic ECM with varying stiffness degrees in vitro. Compared with softer matrices (5Kpa), CXPA cell line and PA primary cells exhibited more proliferative and invasive phenotypes in stiffer matrices (50Kpa, p < 0.01). Protein-protein interaction (PPI) analysis of RNA-sequencing data revealed that AR and ERBB-2 expression was associated with TWIST1. Moreover, surgical specimens demonstrated a higher TWIST1 expression in CXPA over PA. After knocking down TWIST1 in CXPA cells, cell proliferation, migration, and invasiveness were significantly inhibited (p < 0.01). Conclusion: Developing CXPA organoids provides a useful model for cancer biology research and drug screening. ECM remodelling, attributed to overproduction of collagen, alternation of collagen alignment, and increased cross-linking, leads to increased ECM stiffness. ECM modification is an important contributor in CXPA tumorigenesis. [ABSTRACT FROM AUTHOR]

Colorectal carcinoma (CRC) is a fatal disease and ranks as the third most prevalent cancer globally. Stemness and drug resistance are the main causes of tumor recurrence in CRC. This study attempted to probe the impact of TWIST1 on CRC stemness and resistance to oxaliplatin and to uncover the underlying regulatory mechanism of TWIST1. mRNA expression data from The Cancer Genome Atlas-CRC were subjected to differential analysis. The target gene in the study was determined according to literature citation. ChIPBase was utilized to predict likely targets downstream of the target gene. Pearson was employed for correlation analysis. Quantitative real-time polymerase chain reaction was used to assess TWIST1 and microfibrillar-associated protein 2 (MFAP2) levels in CRC and normal cells. The cell viability was assayed through cell counting kit-8 and IC50 value was calculated. Flow cytometry was applied to assay the cell apoptosis. Apoptosis assays were applied to evaluate cell apoptosis. CD44, CD133, SOX-2, ERCC1, GST-π, MRP, and P-gp protein expression levels were assayed by Western blot. The targeting relationship between TWIST1 and MFAP2 was ascertained through dual-luciferase and chromatin immunoprecipitation (ChIP). TWIST1 possessed high expression in CRC tissue and cells. TWIST1 knockdown strikingly promoted cell apoptosis and reduced cell stemness and cell resistance to oxaliplatin. Bioinformatics prediction suggested that MFAP2, which was overexpressed in CRC tissue and cells, was the target gene downstream of TWIST1. Dual-luciferase and ChIP assays validated that there was a targeting relationship between TWIST1 and MFAP2. The results of the rescue assay demonstrated that TWIST1 fostered CRC stemness and oxaliplatin resistance by activating MFAP2 expression. These outcomes implied that TWIST1 enhanced CRC stemness and oxaliplatin resistance by activating the transcription of MFAP2. Therefore, TWIST1/MFAP2 axis possibly indicated a mechanism for regulating tumor progression. [ABSTRACT FROM AUTHOR]

Objectives: Epithelial-mesenchymal transition (EMT) of renal tubular epithelial cells (RTECs) is a pathogenic factor for renal interstitial fibrosis (RIF). Interleukin-33 (IL-33) is related to the occurrence and development of RIF, but the underlying mechanism remains unclear. Here, we investigated whether IL-33 mediates the EMT of RTECs by activating the NF-κB/Twist1 signalling pathway. Methods: In vivo, the RIF animal model induced by unilateral ureteral obstruction (UUO) was established. The effects of exogenous IL-33 and anti-IL-33 antibodies were evaluated. In vitro, the EMT of RTECs was induced by IL-33. The inhibition of the nuclear factor kappa-B (NF-κB) by the pyrrolidine dithiocarbamate (PDTC) and the knockdown of the suppression of tumorigenicity 2 (ST2) by small interference RNA were used to observe whether IL-33 mediates the EMT of RTECs through the NF-κB/Twist1 signaling pathway. Results: In vivo, exogenous IL-33 significantly aggravated UUO-induced pathological damage and collagen deposition, down-regulated E-cadherin expression, and up-regulated α-smooth muscle actin and Vimentin expressions. Moreover, exogenous IL-33 increased the levels of phospho-IκB-α (p-IκB-α) and phospho-NF-κB p65 (p-NF-κB p65), NF-κB p65 nuclear translocation, and Twist1 nuclear expression. However, these effects were reversed by the anti-IL-33 antibody. In vitro, the increases in the levels of p-IκB-α, p-NF-κB p65, NF-κB p65 nuclear translocation, and Twist1 nuclear expression induced by IL-33 were inhibited by the knockdown of PDTC or ST2. IL-33-mediated EMT of RTECs was also significantly reversed. However, NF-κB inhibitor PDTC had no significant effect on ST2 expression. Conclusions: The IL-33/ST2 axis may up-regulate the expression of Twist1 through the NF-κB signalling pathway, thereby inducing the EMT of RTECs and leading to RIF. [ABSTRACT FROM AUTHOR]

Purpose: Epithelial-to-mesenchymal transition (EMT) is an important cause of high mortality in breast cancer. Twist1 is one of the EMT transcription factors (EMT-TFs) with a noticeably short half-life, which is regulated by proteasome degradation pathways. Recent studies have found that USP13 stabilizes several specific oncogenic proteins. As yet, however, the relationship between Twist1 and USP13 has not been investigated. Methods: Co-Immunoprecipitation, GST-pulldown, Western blot, qRT-PCR and immunofluorescence assays were used to investigate the role of USP13 in de-ubiquitination of Twist1. Chromatin immunoprecipitation and Luciferase reporter assays were used to investigate the role of Twist1 in inhibiting USP13 reporter transcription. Scratch wound healing, cell migration and invasion assays, and a mouse lung metastases assay were used to investigate the roles of USP13 and Twist1 in promoting breast cancer metastasis. Results: We found that Twist1 can be de-ubiquitinated by USP13. In addition, we found that the protein levels of Twist1 dose-dependently increased with USP13 overexpression, while USP13 knockdown resulted in a decreased expression of endogenous Twist1. We also found that USP13 can directly interact with Twist1 and specifically cleave the K48-linked polyubiquitin chains of Twist1 induced by FBXL14. We found that the effect of USP13 in promoting the migration and invasion capacities of breast cancer cells can at least partly be achieved through its regulation of Twist1, while Twist1 can inhibit the transcriptional activity of USP13. Conclusions: Our data indicate that an interplay between Twist1 and USP13 can form a negative physiological feedback loop. Our findings show that USP13 may play an essential role in breast cancer metastasis by regulating Twist1 and, as such, provide a potential target for the clinical treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Mechanical cues from the extracellular matrix (ECM) regulate various cellular processes via distinct mechanotransduction pathways. In breast cancer, increased ECM stiffness promotes epithelial-to-mesenchymal transition (EMT), cell invasion, and metastasis. Here, we identify a mechanosensitive EPHA2/LYN protein complex regulating EMT and metastasis in response to increasing ECM stiffness during tumor progression. High ECM stiffness leads to ligand-independent phosphorylation of ephrin receptor EPHA2, which recruits and activates the LYN kinase. LYN phosphorylates the EMT transcription factor TWIST1 to release TWIST1 from its cytoplasmic anchor G3BP2 to enter the nucleus, thus triggering EMT and invasion. Genetic and pharmacological inhibition of this pathway prevents breast tumor invasion and metastasis in vivo. In human breast cancer samples, activation of this pathway correlates with collagen fiber alignment, a marker of increasing ECM stiffness. Our findings reveal an EPHA2/LYN/TWIST1 mechanotransduction pathway that responds to mechanical signals from the tumor microenvironment to drive EMT, invasion, and metastasis.

Despite favorable responses to platinum-based chemotherapy in ovarian cancer (OC), chemoresistance is still a major cause of treatment failure. Hence, we develop a novel synthetic agent, COM33, to relieve the chemoresistance caused by carboplatin. The anti-cancerous effects of the combination of COM33 and carboplatin on OC are evaluated by cell viability, wound healing, and transwell invasion assays. A mechanistic investigation is carried out by using RNA-Seq analysis and then verified by western blot analysis and immunofluorescence microscopy. The safety and efficacy in vivo are evaluated using SKOV3 tumor-bearing nude mice. Results show that the co-administration of COM33 enhances the inhibitory effects of carboplatin on cancer cell viability, migration, and invasion in vitro and tumor growth in vivo. Furthermore, COM33 suppresses the carboplatin-induced epithelial-mesenchymal transition (EMT) by inhibiting the ERK signaling pathway. Additionally, we show that Twist1, the effector of the ERK signaling pathway, participates in carboplatin-induced EMT and is also inhibited by COM33. Our data show that the combination of carboplatin with COM33 is beneficial for chemotherapy against OC, which may be a potential novel anti-tumor strategy.

Abstract Background Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers worldwide. Overexpression of EMT master transcription factors can promote differentiated cells to undergo cancer reprogramming processes and acquire a stem cell-like status. Methods The KYSE-30 and YM-1 ESCC cell lines were transduced with retroviruses expressing TWIST1 or GFP and analyzed by quantitative reverse transcription PCR (qRT-PCR), chromatin immunoprecipitation (ChIP), and immunostaining to investigate the correlation between TWIST1 and stemness markers expression. Cells expressing TWIST1 were characterized for mRNA candidates by qRT-PCR and for protein candidates by Flow cytometry and Immunocytochemistry. TWIST1-ESCC cells were also evaluated for apoptosis and drug resistance. Results Here we identify a role for TWIST1 in the establishment of ESCC cancer stem cell (CSC)-like phenotype, facilitating the transformation of non-CSCs to CSCs. We provide evidence that TWIST1 expression correlates with the expression of CSC markers in ESCC cell lines. ChIP assay results demonstrated that TWIST1 regulates CSC markers, including CD44, SALL4, NANOG, MEIS1, GDF3, and SOX2, through binding to the E-box sequences in their promoters. TWIST1 promoted EMT through E-cadherin downregulation and vimentin upregulation. Moreover, TWIST1 expression repressed apoptosis in ESCC cells through upregulation of Bcl-2 and downregulation of the Bax protein, and increased ABCG2 and ABCC4 transporters expression, which may lead to drug resistance. Conclusions These findings support a critical role for TWIST1 in CSC-like generation, EMT progression, and inhibition of apoptosis in ESCC. Thus, TWIST1 represents a therapeutic target for the suppression of esophageal cell transformation to CSCs and ESCC malignancy.

Studies have reported that megakaryocytic leukemia 1 (MKL1) is closely related to the pathological process of a variety of inflammatory diseases, but its role in osteoarthritis (OA) needs to be clarified. This study aimed to investigate the regulatory role of MKL1 in oxidative stress-induced chondrocyte apoptosis and cartilage matrix degeneration. The expressions of target mRNAs and proteins were measured by using reverse transcription-quantitative polymerase chain reaction and western blotting. ELISA assay was used to measure the levels of IL-6, IL-8, and TNF-α in chondrocytes. And commercial kits based on different spectrophotometry or colorimetry methods were performed to validate oxidative stress. CCK-8 and apoptosis kits were used to determine cell viability and apoptosis. Rat OA model was established by anterior cruciate ligament transection (ACLT), and the expression of MKL1 was interfered by injecting sh-MKL1 lentiviral vector into caudal vein. The results showed that the expression of MKL1was induced by H2O2 in chondrocytes. Knockdown of MKL1 alleviated H2O2-induced inflammation and cell apoptosis, reduced H2O2-induced oxidative stress, and improved cartilage matrix degeneration of chondrocytes. Besides, inhibition of MKL1 regulated the activation of TWIST1-mediated PI3K/AKT signaling. Further studies have found that TWIST1-mediated PI3K/AKT signaling was involved in the regulation mechanism of MKL1 on chondrocyte apoptosis and cartilage matrix degeneration. Next, intervention with MKL1 inhibited the progression of OA in rats. These results demonstrated that MKL1 regulate the apoptosis and cartilage matrix degeneration of chondrocytes via TWIST1-mediated PI3K/AKT signaling.