A dominant negative mutation of GhMYB25-like alters cotton fiber initiation, reducing lint and fuzz.

Cotton (Gossypium hirsutum) fibers, vital natural textile materials, are single-cell trichomes that differentiate from the ovule epidermis. These fibers are categorized as lint (longer fibers useful for spinning) or fuzz (shorter, less useful fibers). Currently, developing cotton varieties with high lint yield but without fuzz remains challenging due to our limited knowledge of the molecular mechanisms underlying fiber initiation. This study presents the identification and characterization of a naturally occurring dominant negative mutation GhMYB25-like_AthapT, which results in a reduced lint and fuzzless phenotype. The GhMYB25-like_AthapT protein exerts its dominant negative effect by suppressing the activity of GhMYB25-like during lint and fuzz initiation. Intriguingly, the negative effect of GhMYB25-like_AthapT could be alleviated by high expression levels of GhMYB25-like. We also uncovered the role of GhMYB25-like in regulating the expression of key genes such as GhPDF2 (PROTODERMAL FACTOR 2), CYCD3; 1 (CYCLIN D3; 1), and PLD (Phospholipase D), establishing its significance as a pivotal transcription factor in fiber initiation. We identified other genes within this regulatory network, expanding our understanding of the determinants of fiber cell fate. These findings offer valuable insights for cotton breeding and contribute to our fundamental understanding of fiber development.

VERU-111, an Orally Available Tubulin Inhibitor, Suppresses Ovarian Tumor Growth and Metastasis.

Ovarian cancer is the most lethal gynecological malignancy, with a 5-year survival rate of approximately 50%. The dismal prognosis is due in part to metastatic disease and acquired drug resistance to conventional chemotherapies such as taxanes. Colchicine binding site inhibitors (CBSIs) are attractive alternatives to taxanes because they could potentially achieve oral bioavailability and overcome drug resistance associated with the prolonged use of taxanes. VERU-111 is one of the most advanced CBSIs that is orally available, potent, well-tolerated, and has shown good efficacy in several preclinical solid tumor models. Here, we demonstrate for the first time the in vitro potency of VERU-111 as well as its efficacy at inhibiting tumor growth and metastasis in an orthotopic ovarian cancer mouse model. VERU-111 has nanomolar potency against ovarian cancer cell lines and strongly inhibits colony formation, proliferation, invasion, and migration. VERU-111 disrupts microtubule formation to induce mitotic catastrophe and, ultimately, apoptosis in a concentration-dependent manner. The efficacy of VERU-111 was comparable with standard chemotherapy paclitaxel, the current first-line treatment for ovarian cancer, with no observed synergy with combination paclitaxel + VERU-111 treatment. In vivo, VERU-111 markedly suppressed ovarian tumor growth and completely suppressed distant organ metastasis. Together, these results support VERU-111 for its potential as a novel therapy for ovarian cancer, particularly for late-stage metastatic disease. Significance Statement VERU-111 is an investigational new drug and has comparable efficacy as paclitaxel in suppressing tumor cell proliferation, colony formation, and migration in ovarian cancer models in vitro and has potent in vivo anti-tumor and anti-metastatic activity in an orthotopic ovarian cancer mouse model. VERU-111 has low systemic toxicity and, unlike paclitaxel, is orally bioavailable and is not a substrate for the major drug efflux transporters, making it a promising and attractive alternative to taxane-based therapy.

GhWER controls fiber initiation and early elongation by regulating ethylene signaling pathway in cotton (Gossypium hirsutum).

Cotton fibers are specialized single-cell trichomes derived from epidermal cells, similar to root hairs and trichomes in Arabidopsis. While the MYB-bHLH-WD40 (MBW) complex has been shown to regulate initiation of both root hairs and trichomes in Arabidopsis, the role of their homologous gene in cotton fiber initiation remains unknown. In this study, we identified a R2R3 MYB transcription factor (TF), GhWER, which exhibited a significant increase in expression within the outer integument of ovule at -1.5 DPA (days post anthesis). Its expression peaked at -1 DPA and then gradually decreased. Knockout of GhWER using CRISPR technology inhibited the initiation and early elongation of fiber initials, resulting in the shorter mature fiber length. Additionally, GhWER interacted with two bHLH TF, GhDEL65 and GhbHLH121, suggesting a potential regulatory complex for fiber development. RNA-seq analysis of the outer integument of the ovule at -1.5 DPA revealed that the signal transduction pathways of ethylene, auxin and gibberellin were affected in the GhWER knockout lines. Further examination demonstrated that GhWER directly activated ethylene signaling genes, including ACS1 and ETR2. These findings highlighted the biological function of GhWER in regulating cotton fiber initiation and early elongation, which has practical significance for improving fiber quality and yield. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01477-6.

Synthesis, biological activity and mechanism of action of novel allosecurinine derivatives as potential antitumor agents.

Cancer with low survival rates is the second main cause of death among all diseases in the world and consequently, effective antineoplastic agents are urgently needed. Allosecurinine is a plant-derived indolicidine securinega alkaloid shown bioactivity. The object of this study is to investigate synthetic allosecurinine derivatives with considerable anticancer capacity against nine human cancer cell lines as well as mechanism of action. We synthesized twenty-three novel allosecurinine derivatives and evaluated their antitumor activity against nine cancer cell lines for 72 h by MTT and CCK8 assays. FCM was applied to analyze the apoptosis, mitochondrial membrane potential, DNA content, ROS production, CD11b expression. Western blot was selected to analyze the protein expression. Structure-activity relationships were established and potential anticancer lead BA-3 which induced differentiation of leukemia cells towards granulocytosis at low concentration and apoptosis at high concentration was identified. Mechanism studies showed that mitochondrial pathway mediated apoptosis within cancer cells with cell cycle blocking was induced by BA-3. In addition, western blot assays revealed that BA-3 induced expression of the proapoptotic factor Bax, p21 and reduced the levels of antiapoptotic protein such as Bcl-2, XIAP, YAP1, PARP, STAT3, p-STAT3, and c-Myc. Collectively, BA-3 was a lead compound for oncotherapy at least in part, through the STAT3 pathway. These results were an important step in further studies on allosecurinine-based antitumor agent development.

Comparative Genome Analyses Highlight Transposon-Mediated Genome Expansion and the Evolutionary Architecture of 3D Genomic Folding in Cotton.

Transposable element (TE) amplification has been recognized as a driving force mediating genome size expansion and evolution, but the consequences for shaping 3D genomic architecture remains largely unknown in plants. Here, we report reference-grade genome assemblies for three species of cotton ranging 3-fold in genome size, namely Gossypium rotundifolium (K2), G. arboreum (A2), and G. raimondii (D5), using Oxford Nanopore Technologies. Comparative genome analyses document the details of lineage-specific TE amplification contributing to the large genome size differences (K2, 2.44 Gb; A2, 1.62 Gb; D5, 750.19 Mb) and indicate relatively conserved gene content and synteny relationships among genomes. We found that approximately 17% of syntenic genes exhibit chromatin status change between active ("A") and inactive ("B") compartments, and TE amplification was associated with the increase of the proportion of A compartment in gene regions (∼7,000 genes) in K2 and A2 relative to D5. Only 42% of topologically associating domain (TAD) boundaries were conserved among the three genomes. Our data implicate recent amplification of TEs following the formation of lineage-specific TAD boundaries. This study sheds light on the role of transposon-mediated genome expansion in the evolution of higher-order chromatin structure in plants.

Single-cell RNA-seq reveals fate determination control of an individual fibre cell initiation in cotton (Gossypium hirsutum).

Cotton fibre is a unicellular seed trichome, and lint fibre initials per seed as a factor determines fibre yield. However, the mechanisms controlling fibre initiation from ovule epidermis are not understood well enough. Here, with single-cell RNA sequencing (scRNA-seq), a total of 14 535 cells were identified from cotton ovule outer integument of Xu142_LF line at four developmental stages (1.5, 1, 0.5 days before anthesis and the day of anthesis). Three major cell types, fibre, non-fibre epidermis and outer pigment layer were identified and then verified by RNA in situ hybridization. A comparative analysis on scRNA-seq data between Xu142 and its fibreless mutant Xu142 fl further confirmed fibre cluster definition. The developmental trajectory of fibre cell was reconstructed, and fibre cell was identified differentiated at 1 day before anthesis. Gene regulatory networks at four stages revealed the spatiotemporal pattern of core transcription factors, and MYB25-like and HOX3 were demonstrated played key roles as commanders in fibre differentiation and tip-biased diffuse growth respectively. A model for early development of a single fibre cell was proposed here, which sheds light on further deciphering mechanism of plant trichome and the improvement of cotton fibre yield.

Treatment of Experimental Choroidal Neovascularization via RUNX1 Inhibition.

Choroidal neovascularization (CNV) is a prevalent cause of vision loss in patients with age-related macular degeneration. Runt-related transcription factor 1 (RUNX1) has been identified as an important mediator of aberrant retinal angiogenesis in proliferative diabetic retinopathy and its modulation has proven to be effective in curbing pathologic angiogenesis in experimental oxygen-induced retinopathy. However, its role in CNV remains to be elucidated. This study demonstrates RUNX1 expression in critical cell types involved in a laser-induced model of CNV in mice. Furthermore, the preclinical efficacy of Ro5-3335, a small molecule inhibitor of RUNX1, in experimental CNV is reported. RUNX1 inhibitor Ro5-3335, aflibercept-an FDA-approved vascular endothelial growth factor (VEGF) inhibitor, or a combination of both, were administered by intravitreal injection immediately after laser injury. The CNV area of choroidal flatmounts was evaluated by immunostaining with isolectin B4, and vascular permeability was analyzed by fluorescein angiography. A single intravitreal injection of Ro5-3335 significantly decreased the CNV area 7 days after laser injury, and when combined with aflibercept, reduced vascular leakage more effectively than aflibercept alone. These data suggest that RUNX1 inhibition alone or in combination with anti-VEGF drugs may be a new therapy upon further clinical validation for patients with neovascular age-related macular degeneration.

Sprouty and Spred temporally regulate ERK1/2-signaling to suppress TGFß-induced lens EMT.

Epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) principally contributes to the pathogenesis of fibrotic cataract. Sprouty (Spry) and Spred proteins are receptor tyrosine kinase (RTK) antagonists that can regulate RTK-mediated signaling pathways, such as the MAPK/ERK1/2-signaling pathway. The present study examines the ability of Spry and Spred to inhibit TGFß-induced EMT in LECs. LECs explanted from postnatal-day-21 Wistar rats were transduced with adenoviral vectors coding for Spry1, Spry2 or Spred2, and subsequently treated with or without TGFß2. Immunofluorescent labeling of explants for the epithelial membrane marker ß-catenin, and the mesenchymal marker alpha-smooth muscle actin (α-sma), were used to characterize the progression of EMT. Western blotting was used to quantify levels of α-sma and ERK1/2-signaling. Overexpression of Spry or Spred in LECs was sufficient to suppress EMT in response to TGFß, including a block to cell elongation, ß-catenin delocalization and α-sma accumulation. Spry and Spred were also shown to significantly block ERK1/2 phosphorylation for up to 18 h of TGFß treatment but did not impair the earlier activation of ERK1/2 at 20 min. These findings suggest that Spry and Spred may not directly impact ERK1/2-signaling activated by the serine/threonine kinase TGFß receptor, but may selectively target later ERK1/2-signaling driven by downstream RTK-mediated signaling. Taken together, our data establish Spry and Spred antagonists as potent negative regulators of TGFß-induced EMT that can regulate ERK1/2-signaling in a temporal manner. A greater understanding of how Spry and Spred regulate the complex signaling interactions that underlie TGFß-induced EMT will be essential to facilitate the development of novel therapeutics for different pathologies driven by EMT, including fibrotic forms of cataract.

Serum miR-377 Can Be Used as a Diagnostic Marker for Acute Coronary Syndrome and Can Regulate Proinflammatory Factors and Endothelial Injury Markers.

The diagnostic value of microRNA-377 (miR-377) in patients with acute coronary syndrome (ACS) and explored miR-377's potential mechanisms. We performed an qRT-PCR to assess serum miR-377 levels in ACS patients and coronary artery ligation rat models. The diagnostic value of miR-377 was evaluated by determining the ROC curve. An ELISA assay was conducted to detect the model rat endothelial damage markers von Willebrand factor (vWF) and heart-type fatty acid binding protein (H-FABP), and proinflammatory cytokines TNF-α, IL-6, and IL-1ß. The serum miR-377 level was elevated in the ACS patients and significantly increased in the ACS rats. MiR-377 has a high diagnostic value in ACS patients, with a 0.844 ROC, 76.47% specificity, and 87.10% sensitivity. MiR-377 was positively correlated with the expressions of vWF, H-FABP, cTnI, TNF-α, IL-6, and IL-1ß. In ACS rats, reducing the expression of miR-377 significantly inhibited the increases in vWF, H-FABP, TNF-α, IL-6, and IL-1ß. An elevated miR-377 level can be used as a diagnostic marker in patients with ACS. A reduction of miR-377 may alleviate ACS by improving myocardial damage such as endothelial injury and the inflammatory response.

Spred negatively regulates lens growth by modulating epithelial cell proliferation and fiber differentiation.

Spred, like Sprouty (Spry) and also Sef proteins, have been identified as important regulators of receptor tyrosine kinase (RTK)-mediated MAPK/ERK-signaling in various developmental systems, controlling cellular processes such as proliferation, migration and differentiation. Spreds are widely expressed during early embryogenesis, and in the eye lens, become more localised in the lens epithelium with later development, overlapping with other antagonists including Spry. Given the synexpression of Spreds and Spry in lens, in order to gain a better understanding of their specific roles in regulating growth factor mediated-signaling and cell behavior, we established and characterised lines of transgenic mice overexpressing Spred1 or Spred2, specifically in the lens. This overexpression of Spreds resulted in a small lens phenotype during ocular morphogenesis, retarding its growth by compromising epithelial cell proliferation and fiber differentiation. These in situ findings were shown to be dependent on the ability of Spreds to suppress MAPK-signaling, in particular FGF-induced ERK1/2-signaling in lens cells. This was validated in vitro using lens epithelial explants, that highlighted the overlapping role of Spreds with Spry2, but not Spry1. This study provides insights into the putative function of Spreds and Spry in situ, some overlapping and some distinct, and their importance in regulating lens cell proliferation and fiber differentiation contributing to lens and eye growth.

Knockdown of survivin results in inhibition of epithelial to mesenchymal transition in retinal pigment epithelial cells by attenuating the TGFß pathway.

Proliferative vitreoretinopathy (PVR) is a common complication of open globe injury and the most common cause of failed retinal detachment surgery. The response by retinal pigment epithelial (RPE) cells liberated into the vitreous includes proliferation and migration; most importantly, epithelial to mesenchymal transition (EMT) of RPE plays a central role in the development and progress of PVR. For the first time, we show that knockdown of BIRC5, a member of the inhibitor of apoptosis protein family, using either lentiviral vector based CRISPR/Cas9 nickase gene editing or inhibition of survivin using the small-molecule inhibitor YM155, results in the suppression of EMT in RPE cells. Knockdown of survivin or inhibition of survivin significantly reduced TGFß-induced cell proliferation and migration. We further demonstrated that knockdown or inhibition of survivin attenuated the TGFß signaling by showing reduced phospho-SMAD2 in BIRC5 knockdown or YM155-treated cells compared to controls. Inhibition of the TGFß pathway using TGFß receptor inhibitor also suppressed survivin expression in RPE cells. Our studies demonstrate that survivin contributes to EMT by cross-talking with the TGFß pathway in RPE cells. Targeting survivin using small-molecule inhibitors may provide a novel approach to treat PVR disease.

Transcriptomic repertoires depict the initiation of lint and fuzz fibres in cotton (Gossypium hirsutum L.).

Cotton fibre is an important natural fibre for the textile industry. The number of fibre initials determines the lint percentage, which is an important factor for cotton fibre yield. Although fibre development has been described by transcriptomic analysis, the mechanism by which the long noncoding RNA manipulates the initiation of lint and fuzz fibres remains unknown. In this study, three lines with different lint percentages were developed by crossing Xu142 with its fibreless mutant Xu142 fl. We collected the epidermal cells from the ovules with attached fibres at 0 and 5 days post anthesis (DPA) from Xu142, the fibreless mutant Xu142 fl and the three lint percent diversified lines for deep transcriptome sequencing. A total of 2641 novel genes, 35 802 long noncoding RNAs (lncRNAs) and 2262 circular RNAs (circRNAs) were identified, of which 645 lncRNAs were preferentially expressed in the fibreless mutant Xu142 fl and 651 lncRNAs were preferentially expressed in the fibre-attached lines. We demonstrated the functional roles of the three lncRNAs in fibre development via a virus-induced gene silencing (VIGS) system. Our results showed that silencing XLOC_545639 and XLOC_039050 in Xu142 fl increased the number of fibre initials on the ovules, but silencing XLOC_079089 in Xu142 resulted in a short fibre phenotype. This study established the transcriptomic repertoires in cotton fibre initiation and provided evidence for the potential functions of lncRNAs in fibre development.

Negative regulation of lens fiber cell differentiation by RTK antagonists Spry and Spred.

Sprouty (Spry) and Spred proteins have been identified as closely related negative regulators of the receptor tyrosine kinase (RTK)-mediated MAPK pathway, inhibiting cellular proliferation, migration and differentiation in many systems. As the different members of this antagonist family are strongly expressed in the lens epithelium in overlapping patterns, in this study we used lens epithelial explants to examine the impact of these different antagonists on the morphologic and molecular changes associated with fibroblast growth factor (FGF)-induced lens fiber differentiation. Cells in lens epithelial explants were transfected using different approaches to overexpress the different Spry (Spry1, Spry2) and Spred (Spred1, Spred2, Spred3) members, and we compared their ability to undergo FGF-induced fiber differentiation. In cells overexpressing any of the antagonists, the propensity for FGF-induced cell elongation was significantly reduced, indicative of a block to lens fiber differentiation. Of these antagonists, Spry1 and Spred2 appeared to be the most potent among their respective family members, demonstrating the greatest block in FGF-induced fiber differentiation based on the percentage of cells that failed to elongate. Consistent with the reported activity of Spry and Spred, we show that overexpression of Spry2 was able to suppress FGF-induced ERK1/2 phosphorylation in lens cells, as well as the ERK1/2-dependent fiber-specific marker Prox1, but not the accumulation of ß-crystallins. Taken together, Spry and Spred proteins that are predominantly expressed in the lens epithelium in situ, appear to have overlapping effects on negatively regulating ERK1/2-signaling associated with FGF-induced lens epithelial cell elongation leading to fiber differentiation. This highlights the important regulatory role for these RTK antagonists in establishing and maintaining the distinct architecture and polarity of the lens.

KLF4 expression enhances the efficacy of chemotherapy drugs in ovarian cancer cells.

KLF4 is a transcriptional factor that can function either as a tumor suppressor or oncogene in cancer based on its cellular context. We recently demonstrated that KLF4 was a tumor suppressor in ovarian cancer cells by inhibiting the epithelial to mesenchymal transition. Here we report that KLF4 expression was downregulated in ovarian cancer tissue compared to normal ovarian tissue, and low KLF4 expression correlated with high risk ovarian carcinoma and poor patient survival. Enforced KLF4 expression by lentiviral transduction sensitized ovarian cancer cells to the effects of the chemotherapy drugs, paclitaxel and cisplatin. Treatment of ovarian cancer cells with APTO-253, a small molecule inducer of KLF4, enhanced the efficacy of both chemotherapy drugs. KLF4 expression mediated by lentiviral vector or induced by APTO-253 resulted in G1 phase arrest in ovarian cancer cells. Our results demonstrate that for the first time that inducing KLF4 expression with APTO-253 is a novel therapeutic strategy for treating ovarian cancer.

Sprouty gain of function disrupts lens cellular processes and growth by restricting RTK signaling.

Sprouty proteins function as negative regulators of the receptor tyrosine kinase (RTK)-mediated Ras/Raf/MAPK pathway in many varied physiological and developmental processes, inhibiting growth factor-induced cellular proliferation, migration and differentiation. Like other negative regulators, Sprouty proteins are expressed in various organs during development, including the eye; ubiquitously expressed in the optic vesicle, lens pit, optic cup and lens vesicle. Given the synexpression of different antagonists (e.g, Sprouty, Sef, Spred) in the developing lens, to gain a better understanding of their specific role, in particular, their ability to regulate ocular growth factor signaling in lens cells, we characterized transgenic mice overexpressing Sprouty1 or Sprouty2 in the eye. Overexpression of Sprouty in the lens resulted in reduced lens and eye size during ocular morphogenesis, influenced by changes to the lens epithelium, aberrant fiber cell differentiation and compromised de novo maintenance of the lens capsule. Here we demonstrate an important inhibitory role for Sprouty in the regulation of lens cell proliferation and fiber differentiation in situ, potentially through its ability to modulate FGF- (and even EGF-) mediated MAPK/ERK1/2 signaling in lens cells. Whilst growth factor regulation of lens cell proliferation and fiber differentiation are required for orchestrating lens morphogenesis and growth, in turn, antagonists such as Sprouty are just as important for regulating the intracellular signaling pathways driving lens cellular processes.

Negative regulation of TGFß-induced lens epithelial to mesenchymal transition (EMT) by RTK antagonists.

An eclectic range of ocular growth factors with differing actions are present within the aqueous and vitreous humors that bathe the lens. Growth factors that exert their actions via receptor tyrosine kinases (RTKs), such as FGF, play a normal regulatory role in lens; whereas other factors, such as TGFß, can lead to an epithelial to mesenchymal transition (EMT) that underlies several forms of cataract. The respective downstream intracellular signaling pathways of these factors are in turn tightly regulated. One level of negative regulation is thought to be through RTK-antagonists, namely, Sprouty (Spry), Sef and Spred that are all expressed in the lens. In this study, we tested these different negative regulators and compared their ability to block TGFß-induced EMT in rat lens epithelial cells. Spred expression within the rodent eye was confirmed using RT-PCR, western blotting and immunofluorescence. Rat lens epithelial explants were used to examine the morphological changes associated with TGFß-induced EMT over 3 days of culture, as well as α-smooth muscle actin (α-sma) immunolabeling. Cells in lens epithelial explants were transfected with either a reporter (EGFP) vector (pLXSG), or with plasmids also coding for different RTK-antagonists (i.e. pLSXG-Spry1, pLSXG-Spry2, pLXSG-Sef, pLSXG-Spred1, pLSXG-Spred2, pLSXG-Spred3), before treating with TGFß for up to 3 days. The percentages of transfected cells that underwent TGFß-induced morphological changes consistent with an EMT were determined using cell counts and validated with a paired two-tailed t-test. Explants transfected with pLXSG demonstrated a distinct transition in cell morphology after TGFß treatment, with ∼60% of the cells undergoing fibrotic-like cell elongation. This percentage was significantly reduced in cells overexpressing the different antagonists, indicative of a block in lens EMT. Of the antagonists tested under these in vitro conditions, Spred1 was the most potent demonstrating the greatest block in TGFß-induced fibrotic cell elongation/EMT. Through the overexpression of RTK-antagonists in lens epithelial cells we have established a novel role for Spry, Spred and Sef as negative regulators of TGFß-induced EMT. Further investigations may help us develop a better understanding of the molecular mechanisms involved in maintaining the integrity of the normal lens epithelium, with these antagonists serving as putative therapeutic agents for prevention of EMT, and hence cataractogenesis.

Depleted miR-125a-5p Causes Vascular Endothelial Cell Dysfunction in Deep Vein Thrombosis by Targeting Angiopoietin 2.

Deep vein thrombosis (DVT) is a common and fatal disease with a pathology involving endothelial dysfunction. The present research aimed to address the potential clinical significance of miR-125a-5p in DVT and its effect on the dysfunction of Human umbilical vein endothelial cells (HUVECs). Serum miR-125a-5p levels were measured using RT-qPCR in 88 patients with DVT and 76 healthy controls. ROC was plotted to evaluate the diagnostic potential of miR-125a-5p. Spearman's correlation coefficient was performed to calculate the correlation between miR-125a-5p and clinical indicators. CCK-8, Transwell, and ELISA were employed to verify the effects of cell proliferation, migration, and inflammatory and adhesion molecules. Dual-luciferase reporter assay to analyze potential target for miR-125a-5p. Serum miR-125a-5p was reduced in patients with DVT compared with healthy controls (P < 0.001). ROC showed that miR-125a-5p significantly identified patients with DVT from the healthy controls (AUC = 0.834). Furthermore, serum miR-125a-5p was negatively correlated with inflammatory factors and coagulation factors. In in vitro studies, proliferation and migration of HUVECs were inhibited by suppressed miR-125a-5p, whereas inflammation and adhesion factors were considerably promoted (P < 0.05). Moreover, miR-125-5p directly targeted the 3'UTR of angiopoietin 2 (ANGPT2) and was negatively regulated. Finally, serum ANGPT2 was elevated in patients with DVT and was negatively correlated with serum miR-125a-5p. The current research demonstrated that decreased miR-125a-5p was a novel potential diagnostic biomarker for DVT and that it may be involved in DVT progression by targeting ANGPT2 to regulate endothelial dysfunction.

FAK PROTAC Inhibits Ovarian Tumor Growth and Metastasis by Disrupting Kinase Dependent and Independent Pathways.

Focal adhesion kinase (FAK) is highly expressed in a variety of human cancers and is a target for cancer therapy. Since FAK kinase inhibitors only block the kinase activity of FAK, they are not highly effective in clinical trials. FAK also functions as a scaffold protein in a kinase-independent pathway. To effectively target FAK, it is required to block both FAK kinase-dependent and FAK-independent pathways. Thus, we tested a new generation drug FAK PROTAC for ovarian cancer therapy, which blocks both kinase and scaffold activity. We tested the efficacy of FAK PROTAC and its parent kinase inhibitor (VS-6063) in ovarian cancer cell lines in vitro by performing cell functional assays including cell proliferation, migration, invasion. We also tested in vivo activity in orthotopic ovarian cancer mouse models. In addition, we assessed whether FAK PROTAC disrupts kinase-dependent and kinase-independent pathways. We demonstrated that FAK PROTAC is highly effective as compared to its parent FAK kinase inhibitor VS-6063 in inhibiting cell proliferation, survival, migration, and invasion. FAK PROTAC not only inhibits the FAK kinase activity but also FAK scaffold function by disrupting the interaction between FAK and its interaction protein ASAP1. We further showed that FAK PROTAC effectively inhibits ovarian tumor growth and metastasis. Taken together, FAK PROTAC inhibits both FAK kinase activity and its scaffold protein activity by disrupting the interaction between FAK and ASAP1 and is highly effective in inhibiting ovarian tumor growth and metastasis.

Cryptotanshinone inhibits ovarian tumor growth and metastasis by degrading c-Myc and attenuating the FAK signaling pathway.

Cryptotanshinone (CT), a natural compound derived from Salvia miltiorrhiza Bunge that is also known as the traditional Chinese medicine Danshen, exhibits antitumor activity in various cancers. However, it remains unclear whether CT has a potential therapeutic benefit against ovarian cancers. The aim of this study was to test the efficacy of CT in ovarian cancer cells in vitro and using a xenograft model in NSG mice orthotopically implanted with HEY A8 human ovarian cancer cells and to explore the molecular mechanism(s) underlying CT's antitumor effects. We found that CT inhibited the proliferation, migration, and invasion of OVCAR3 and HEY A8 cells, while sensitizing the cell responses to the chemotherapy drugs paclitaxel and cisplatin. CT also suppressed ovarian tumor growth and metastasis in immunocompromised mice orthotopically inoculated with HEY A8 cells. Mechanistically, CT degraded the protein encoded by the oncogene c-Myc by promoting its ubiquitination and disrupting the interaction with its partner protein Max. CT also attenuated signaling via the nuclear focal adhesion kinase (FAK) pathway and degraded FAK protein in both cell lines. Knockdown of c-Myc using lentiviral CRISPR/Cas9 nickase resulted in reduction of FAK expression, which phenocopies the effects of CT and the c-Myc/Max inhibitor 10058-F4. Taken together, our studies demonstrate that CT inhibits primary ovarian tumor growth and metastasis by degrading c-Myc and FAK and attenuating the FAK signaling pathway.

Synthesis and biological evaluation of selective survivin inhibitors derived from the MX-106 hydroxyquinoline scaffold.

The survivin (BIRC5) expression is very low in normal differentiated adult tissues, but it is one of the most widely upregulated genes in tumor cells. The overexpression of survivin in many cancer types has been positively correlated with resistance to chemotherapy, tumor metastasis, and poor patient survival. Survivin is considered to be a cancer specific biomarker and serves as a potential cancer drug target. In this report, we describe the design and syntheses of a series of novel selective survivin inhibitors based on the hydroxyquinoline scaffold from our previously reported lead compound MX-106. The best compound identified in this study is compound 12b. In vitro, 12b inhibited cancer cell proliferation with an average IC50 value of 1.4 µM, using a panel of melanoma, breast, and ovarian cancer cell lines. The metabolic stability of 12b improved over MX-106 by 1.7-fold (88 vs 51 min in human microsomes). Western blot analyses demonstrated that treatments with 12b selectively decreased survivin protein levels, but negligibly affected other closely related members in the IAP family proteins, and strongly induced cancer cell apoptosis. In vivo, compound 12b effectively inhibited melanoma tumor growth when tested using a human A375 melanoma xenograft model. Further evaluation using an aggressive, orthotopic ovarian cancer mouse model showed that 12b was highly efficacious in suppressing both primary tumor growth in ovaries and tumor metastasis to multiple peritoneal organs. Collectively, results in this study strongly suggest that the hydroxyquinoline scaffold, represented by 12b and our earlier lead compound MX-106, has abilities to selectively target survivin and is promising for further preclinical development.