Vitexicarpin suppresses malignant progression of colorectal cancer through affecting c-Myc ubiquitination by targeting IMPDH2.

BACKGROUND: Colorectal cancer (CRC) is the second most common cause of cancer-related mortality and is characterised by extensive invasive and metastatic potential. Previous studies have shown that vitexicarpin extracted from the fruits of Vitex rotundifolia can impede tumour progression. However, the molecular mechanisms involved in CRC treatment are still not fully established. PURPOSE: Our study aimed to investigate the anticancer activity, targets, and molecular mechanisms of vitexicarpin in CRC hoping to provide novel therapies for patients with CRC. STUDY DESIGN/METHODS: The impact of vitexicarpin on CRC was assessed through various experiments including MTT, clone formation, EDU, cell cycle, and apoptosis assays, as well as a tumour xenograft model. CETSA, label-free quantitative proteomics, and Biacore were used to identify the vitexicarpin targets. WB, Co-IP, Ubiquitination assay, IF, molecular docking, MST, and cell transfection were used to investigate the mechanism of action of vitexicarpin in CRC cells. Furthermore, we analysed the expression patterns and correlation of target proteins in TCGA and GEPIA datasets and clinical samples. Finally, wound healing, Transwell, tail vein injection model, and tissue section staining were used to demonstrate the antimetastatic effect of vitexicarpin on CRC in vitro and in vivo. RESULTS: Our findings demonstrated that vitexicarpin exhibits anticancer activity by directly binding to inosine monophosphate dehydrogenase 2 (IMPDH2) and that it promotes c-Myc ubiquitination by disrupting the interaction between IMPDH2 and c-Myc, leading to epithelial-mesenchymal transition (EMT) inhibition. Vitexicarpin hinders the migration and invasion of CRC cells by reversing EMT both in vitro and in vivo. Additionally, these results were validated by the overexpression and knockdown of IMPDH2 in CRC cells. CONCLUSION: These results demonstrated that vitexicarpin regulates the interaction between IMPDH2 and c-Myc to inhibit CRC proliferation and metastasis both in vitro and in vivo. These discoveries introduce potential molecular targets for CRC treatment and shed light on new mechanisms for c-Myc regulation in tumours.

Sexually dimorphic effects of estrogen receptor 2 deletion in the dorsal raphe nucleus on emotional behaviors.

Sex differences in emotional behaviors and affective disorders have been widely noted, of which sexually dimorphic secretion of gonadal steroid hormones such as estrogen is suspected to play a role. However, the underlying neural mechanisms remain poorly understood. We noted that the expression of estrogen receptor 2 (Esr2, or ERß), a key mediator of estrogen signaling in the brain, was enriched in the dorsal raphe nucleus (DRN), a region involved in emotion regulation. To investigate whether DRN Esr2 expression confers sex-specific susceptibility or vulnerability in emotional behaviors, we generated a conditional allele of Esr2 that allowed for site-specific deletion of Esr2 in the DRN via local injection of Cre-expressing viruses. DRN-specific Esr2 deletion mildly increased anxiety behaviors in females, as shown by decreased time spent in the center zone of an open field in knockout females. By contrast, DRN Esr2 deletion had no effects on anxiety levels in males, as demonstrated by knockout males spending comparable time in the center zone of an open field and open arms of an elevated-plus maze. Furthermore, in the tail suspension test, DRN Esr2 deletion reduced immobility, a depression-like behavior, in a male-biased manner. Together, these results reveal sex-specific functions of DRN Esr2 in regulating emotional behaviors and suggest targeted manipulation of DRN Esr2 signaling as a potential therapeutic strategy to treat sex-biased affective disorders.

A circuit from the ventral subiculum to anterior hypothalamic nucleus GABAergic neurons essential for anxiety-like behavioral avoidance.

Behavioral observations suggest a connection between anxiety and predator defense, but the underlying neural mechanisms remain unclear. Here we examine the role of the anterior hypothalamic nucleus (AHN), a node in the predator defense network, in anxiety-like behaviors. By in vivo recordings in male mice, we find that activity of AHN GABAergic (AHNVgat+) neurons shows individually stable increases when animals approach unfamiliar objects in an open field (OF) or when they explore the open-arm of an elevated plus-maze (EPM). Moreover, object-evoked AHN activity overlap with predator cue responses and correlate with the object and open-arm avoidance. Crucially, exploration-triggered optogenetic inhibition of AHNVgat+ neurons reduces object and open-arm avoidance. Furthermore, retrograde viral tracing identifies the ventral subiculum (vSub) of the hippocampal formation as a significant input to AHNVgat+ neurons in driving avoidance behaviors in anxiogenic situations. Thus, convergent activation of AHNVgat+ neurons serves as a shared mechanism between anxiety and predator defense to promote behavioral avoidance.

Thalidomide-based Pt(IV) prodrugs designed to exert synergistic effect of immunomodulation and chemotherapy.

Combination of immune- and chemo-therapy has become a new trend in cancer treatment. Food and Drug Administration (FDA)-approved immune-modulatory agent, thalidomide, can modulate the related proteins of upstream signaling pathway of programmed cell death-ligand 1 (PD-L1), including nuclear transcription factor κB (NF-κB), hypoxia inducible factor-1α (HIF-1α), epidermal growth factor receptor (EGFR), and signal transducer and activator of transcription 3 (STAT3), all acting as key antitumor target proteins. In this work, we conjugated thalidomide with oxidized cisplatin to construct multi-functional Pt(IV) prodrugs, named thaliplatins 4-6, to investigate the anti-tumor effect of immuno- and chemo-therapy. Among them, thaliplatin 6 exerted remarkable cytotoxicity against the tested cancer cell lines, showing 15-26 and 9-20 times higher IC50 values than those of single cisplatin or the combination of cisplatin + thalidomide, respectively. Moreover, thaliplatin 6 could rapidly accumulated into cells, markedly triggered DNA damage, and induced cell S phase arrest and apoptosis, as well as inhibited cell migration and invasion in breast carcinoma cell line (MCF-7). Fluorescent confocal and western blotting experiments proved that 6 significantly regulated NF-κB, EGFR, HIF-1α and phosphor-signal transducer and activator of transcription 3 (p-STAT3), and simultaneously inhibited PD-L1 expression to interrupt programmed cell death 1 (PD-1)/PD-L1 signaling pathway, suggesting a synergistic action of cisplatin and thalidomide. Most strikingly, in vivo tests indicated that 6 effectively decreased tumor growth with no observable systemic toxicity, being superior to the anticancer efficacy of cisplatin.

Targeting ROS-AMPK pathway by multiaction Platinum(IV) prodrugs containing hypolipidemic drug bezafibrate.

Alterations in lipid metabolism, commonly disregarded in the past, have been accepted as a hallmark for cancer. Exploring cancer therapeutics that interrupt the lipid metabolic pathways by monotherapy or combination with conventional chemotherapy or immunotherapy is of great importance. Here we modified cisplatin with an FDA-approved hypolipidemic drug, bezafibrate (BEZ), via the well-established Pt(IV) strategy, affording two multi-functional Pt(IV) anticancer agents cis,cis,trans-[Pt(NH3)2Cl2(BEZ)(OH)] (CB) and cis,cis,trans-[Pt(NH3)2Cl2(BEZ)2] (CP) (BEZ = bezafibrate). The Pt(IV) prodrug CB exhibited an enhanced anticancer activity up to 187-fold greater than the clinical anticancer drug cisplatin. Both CB and CP had less toxicity to normal cells, showing higher efficacies and superior therapeutic indexes than cisplatin. Mechanism studies revealed that the bezafibrate-conjugated Pt(IV) complex CB, as a representative, could massively accumulate in A549 cells and genomic DNA, induce DNA damage, elevate intracellular ROS levels, perturb mitochondrial transmembrane potentials, activate the cellular metabolic sensor AMPK, and result in profound proliferation inhibition and apoptosis. Further cellular data also provided evidence that phosphorylation of AMPK, as a metabolic sensor, could suppress the downstream HMGB1, NF-κB, and VEGFA, which may contribute to the inhibition of angiogenesis and metastasis. Our study suggests that the antitumor action of CB and CP mechanistically distinct from the conventional platinum drugs and that functionalizing platinum-based agents with lipid-modulating agents may represent a novel practical strategy for cancer treatment.

Ketoplatin in triple-negative breast cancer cells MDA-MB-231: High efficacy and low toxicity, and positive impact on inflammatory microenvironment.

Triple-negative breast cancer (TNBC) shares the molecular features facilitating epithelial-to-mesenchymal transition (EMT), which contributed to tumor invasion and metastasis. A platinum(IV) conjugate ketoplatin deriving from FDA-approved drugs cisplatin and ketoprofen was designed and prepared to enhance antitumor activity and suppress EMT in TNBC via positive impact on inflammatory microenvironment by modulating COX-2 signal. As a prodrug, ketoplatin afforded 50.26-fold higher cytotoxicity than cisplatin against TNBC mesenchymal-stem cell-like MDA-MB-231 cells, partly attributing to its dramatic increase of cellular uptake and DNA damage. More importantly, EMT progress in MDA-MB-231 was markedly restrained by ketoplatin, resulting from the suppression of vimentin and N-cadherin mediated by down-regulated COX-2. Further in vivo investigation exhibited that ketoplatin effectively inhibited tumor growth and reduced systemic toxicity compared to cisplatin. Overall, ketoplatin possessed high antitumor activity and low toxicity against TNBC MDA-MB-231 in vitro and in vivo.

Specific Hypothalamic Neurons Required for Sensing Conspecific Male Cues Relevant to Inter-male Aggression.

The hypothalamus regulates innate social interactions, but how hypothalamic neurons transduce sex-related sensory signals emitted by conspecifics to trigger appropriate behaviors remains unclear. Here, we addressed this issue by identifying specific hypothalamic neurons required for sensing conspecific male cues relevant to inter-male aggression. By in vivo recording of neuronal activities in behaving mice, we showed that neurons expressing dopamine transporter (DAT+) in the ventral premammillary nucleus (PMv) of the hypothalamus responded to male urine cues in a vomeronasal organ (VNO)-dependent manner in naive males. Retrograde trans-synaptic tracing further revealed a specific group of neurons in the bed nucleus of the stria terminalis (BNST) that convey male-relevant signals from VNO to PMv. Inhibition of PMvDAT+ neurons abolished the preference for male urine cues and reduced inter-male attacks, while activation of these neurons promoted urine marking and aggression. Thus, PMvDAT+ neurons exemplify a hypothalamic node that transforms sex-related chemo-signals into recognition and behaviors.

A highly selective colorimetric and fluorescent probe for quantitative detection of Cu2+/Co2+: The unique ON-OFF-ON fluorimetric detection strategy and applications in living cells/zebrafish.

Identifying and detecting similar target cations through combining "turn on" and "turn off" fluorescence mechanism is effective and challenging. Now a new colorimetric and ON-OFF-ON fluorescent probe N'-((7-(diethylamino)-2-oxo-2H-chromen-3-yl)methylene)-3-hydroxy-2-naphthohydrazide (L) was reported, which could detect Cu2+ and Co2+ in phosphate buffered CH3CH2OH-H2O solvent system. With the assistance of glutathione and pH adjustment, a unique ON-OFF-ON fluorescence detection strategy could be achieved for distinguishing Cu2+ and Co2+. The emission of probe could recover from the L-Cu2+ and L-Co2+ system by addition of GSH or adjusting pH value to 4, respectively, which is due to the abolishment of paramagnetic Cu2+/Co2+. Based on fluorescence titration experiments, the limit of detection was determined as 3.84 × 10-9 M and 4.55 × 10-9 M for Cu2+ and Co2+, respectively. Meanwhile, the detection limit reached 6.21 × 10-8 M for Cu2+ and 6.96 × 10-8 M for Co2+ according to absorbance signal output. Fast recognition of Cu2+/Co2+ can be achieved by obvious color changes from green to colorless under UV light, as well as from yellow to orange-red in room light. The binding mode of L toward Cu2+ and Co2+ have been systematically studied by Job's plot analysis, ESI-MS, IR and density functional theory calculations. Most strikingly, further practical applications of the probe L in fluorescence imaging were investigated in MCF-7 cells and zebrafish due to its low cytotoxicity and good optical properties, suggesting that L could serve as a fluorescent sensor for tracking Cu2+ and Co2+in vivo.

Simultaneous determination of ten preservatives in ten kinds of foods by micellar electrokinetic chromatography.

An improved micellar electrokinetic capillary chromatography method (MEKC) for the simultaneous determination of ten preservatives in ten different kinds of food samples was reported. An uncoated fused-silica capillary with 50 µm i.d. and 70 cm total length was used. Under the optimized conditions, the linear response was observed in the range of 1.2-200mg/L for the analytes. The limits of detection (LOD, S/N=3) and limits of quantitation (LOQ, S/N=10) ranging from 0.4 to 0.5mg/L and 1.2 to 1.5mg/L, respectively were obtained. The method was used for the determination of sorbic and benzoic acids in two FAPAS® (Food Analysis Performance Assessment Scheme) proficiency test samples (jam and chocolate cake). The results showed that the current method with simple sample pretreatment and small reagent consumption could meet the needs for routine analysis of the ten preservatives in ten types of food products.

[Effects of H2 relaxin on airway remodeling and expression of cyclin D1 in a murine model of chronic asthma].

OBJECTIVE: To investigate the effects of H(2) Relaxin (Relaxin) on airway remodeling and the expression of cyclin D(1) in a murine model of chronic asthma. METHODS: Forty BALB/c mice were randomly divided into 4 groups:a normal control group, an asthma group, a vehicle control group and a relaxin treatment group, with 10 mice in each. The mice were sensitized and challenged with ovalbumin (OVA) to establish the chronic asthmatic model. The vehicle control group and the relaxin treatment group were subcutaneously injected with saline and relaxin (0.25 mg × kg(-1)× d(-1))respectively. Alteration of the airway inflammation and collagen deposition were observed by haematoxylin-eosin (HE) and Masson staining. Hydroxyproline in the lung was measured by enzyme linked immunosorbent assay (ELISA). The expression of α-smooth muscle actin (α-SMA) in lungs was evaluated by immunohistochemistry. The protein expression and the mRNA of cyclin D(1) were detected by Western blot and RT-PCR respectively. RESULTS: There were inflammatory cell infiltration, airway stenosis, bronchial smooth muscle hypertrophy and increased collagen deposition in the asthmatic group and the vehicle control group; but these changes were significantly ameliorated in the relaxin treatment group. The area of the α-SMA-stained smooth muscle layer in the asthmatic group and the vehicle control group was significantly greater than that in the control group (all P < 0.05), while administration of relaxin decreased the α-SMA immunostained area (all P < 0.05). The lung hydroxyproline content in the asthmatic and the vehicle groups [(0.68 ± 0.10) mg/g lung tissue, (0.67 ± 0.10) mg/g lung tissue] was significantly greater than that in the control group [(0.26 ± 0.05) mg/g lung tissue] (q = 16.61, 16.01 respectively, all P < 0.01). In contrast, treatment with relaxin significantly reduced the lung hydroxyproline content [(0.40 ± 0.06) mg/g lung tissue] compared with aforementioned 2 groups (q = 10.88, 10.26 respectively, all P < 0.05). The results of the Western blot analysis showed that the expression level of cyclin D(1) in the asthmatic and the vehicle groups [(1.38 ± 0.18), (1.50 ± 0.10)] was higher than that in the control group (0.38 ± 0.10) (q = 13.00, 14.65 respectively, all P < 0.05), while it was significantly decreased in the relaxin group (0.72 ± 0.13) (q = 8.51, 10.16 respectively, all P < 0.05). There were no differences in all of the parameters between the asthmatic group and the vehicle group (P > 0.05). CONCLUSION: Relaxin alleviated airway inflammation, airway smooth muscle thickening and airway remodelling in a murine model of chronic asthma, partially by down-regulating the expression level of cyclin D(1).