Selective PI3Kδ inhibitor TYM-3-98 suppresses AKT/mTOR/SREBP1-mediated lipogenesis and promotes ferroptosis in KRAS-mutant colorectal cancer.

Colorectal cancer (CRC) is one of the most common tumors of the digestive system worldwide. KRAS mutations limit the use of anti-EGFR antibodies in combination with chemotherapy for the treatment of CRC. Therefore, novel targeted therapies are needed to overcome the KRAS-induced oncogenesis. Recent evidence suggests that inhibition of PI3K led to ferroptosis, a nonapoptotic cell death closely related to KRAS-mutant cells. Here, we showed that a selective PI3Kδ inhibitor TYM-3-98 can suppress the AKT/mTOR signaling and activate the ferroptosis pathway in KRAS-mutant CRC cells in a concentration-dependent manner. This was evidenced by the lipid peroxidation, iron accumulation, and depletion of GSH. Moreover, the overexpression of the sterol regulatory element-binding protein 1 (SREBP1), a downstream transcription factor regulating lipid metabolism, conferred CRC cells greater resistance to ferroptosis induced by TYM-3-98. In addition, the effect of TYM-3-98 was confirmed in a xenograft mouse model, which demonstrated significant tumor suppression without obvious hepatoxicity or renal toxicity. Taken together, our work demonstrated that the induction of ferroptosis contributed to the PI3Kδ inhibitor-induced cell death via the suppression of AKT/mTOR/SREBP1-mediated lipogenesis, thus displaying a promising therapeutic effect of TYM-3-98 in CRC treatment.

Discovery of NO Donor-Aurovertin Hybrids as Dual Ferroptosis and Apoptosis Inducers for Treating Triple Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is a highly lethal malignancy, and its clinical management encounters severe challenges due to its high metastatic propensity and the absence of effective therapeutic targets. To improve druggability of aurovertin B (AVB), a natural polyketide with a significant antiproliferative effect on TNBC, a series of NO donor/AVB hybrids were synthesized and tested for bioactivities. Among them, compound 4d significantly inhibited the proliferation and metastasis of TNBC in vitro and in vivo with better safety than that of AVB. The structure-activity relationship analysis suggested that the types of NO donor and the linkers had considerable effects on the activities. Mechanistic investigations unveiled that 4d induced apoptosis and ferroptosis by the reduction of mitochondrial membrane potential and the down-regulation of GPX4, respectively. The antimetastatic effect of 4d was associated with the upregulation of DUSP1. Overall, these compelling results underscore the tremendous potential of 4d for treating TNBC.

TYM-3-98, a novel selective inhibitor of PI3Kδ, demonstrates promising preclinical antitumor activity in B-cell lymphomas.

AIMS: PI3Kδ is expressed predominately in leukocytes and is commonly found to be aberrantly activated in human B-cell lymphomas. Although PI3Kδ has been intensively targeted for discovering anti-lymphoma drugs, the application of currently approved PI3Kδ inhibitors has been limited due to unwanted systemic toxicities, thus warranting the development of novel PI3Kδ inhibitors with new scaffolds. MAIN METHODS: We designed TYM-3-98, an indazole derivative, and evaluated its selectivity for all four PI3K isoforms, as well as its efficacy against various B-cell lymphomas both in vitro and in vivo. KEY FINDINGS: We identified TYM-3-98 as a highly selective PI3Kδ inhibitor over other PI3K isoforms at both molecular and cellular levels. It showed superior antiproliferative activity in several B-lymphoma cell lines compared with the approved first-generation PI3Kδ inhibitor idelalisib. TYM-3-98 demonstrated a concentration-dependent PI3K/AKT/mTOR signaling blockage followed by apoptosis induction. In vivo, TYM-3-98 showed good pharmaceutical properties and remarkably reduced tumor growth in a human lymphoma xenograft model and a mouse lymphoma model. SIGNIFICANCE: Our findings establish TYM-3-98 as a promising PI3Kδ inhibitor for the treatment of B-cell lymphoma.

A novel sesquiterpene lactone fraction from Eupatorium chinense L. suppresses hepatocellular carcinoma growth by triggering ferritinophagy and mitochondrial damage.

BACKGROUND: Hepatocellular carcinoma (HCC) is an aggressive tumor with limited treatment options, and it is the third leading cause of cancer-related deaths. Hence, novel therapeutic strategies are required to treat HCC. Eupatorium chinense L. is a traditional Chinese medicine (TCM) that can effectively neutralize heat and smoothen the flow of "Qi" through the liver. However, the anti-HCC effects of Eupatorium chinense L. remain unknown. PURPOSE: The present study investigated the anti-HCC effects and the underlying mechanisms of the electrophilic sesquiterpenes isolated from E. chinense L. (EChLESs) in the regulation of ferroptosis and apoptosis in HCC cells. STUDY DESIGN/METHODS: Cell viability was assessed by the MTT assay. Cell apoptosis was confirmed by flow cytometry and western blotting assay. Ferroptosis was assessed by flow cytometry, transmission electron microscopy, and western blotting assay. Ferritinophagy was detected by acridine orange staining and western blotting assay. Small interfering RNA of nuclear receptor coactivator 4 (NCOA4) was used to confirm the role of ferritinophagy in the therapeutic effect of EChLESs on HCC cells. A mouse xenograft model was constructed to determine the inhibitory effect of EChLESs on HCC in vivo. RESULTS: EChLESs induced apoptosis by disrupting mitochondrial membrane potential depolarization and mitochondrial reactive oxygen species. EChLESs induced ferroptosis as noted by a significant increase in mitochondrial disruption, lipid peroxidation, and intracellular iron level and decreased glutathione level. The apoptosis inhibitor Z-VAD-FMK and lipid reactive oxygen species scavenger ferrostatin 1 attenuated EChLESs-induced cell death. NCOA4-mediated ferritinophagy through autophagic flux was the crucial pathway for ferroptosis induced by EChLESs. NCOA4 knockdown alleviated EChLESs-induced cell death. EChLESs controlled the expression of NCOA4 at the transcriptional and post-transcriptional levels. In the in vivo experiment, EChLESs suppressed HCC growth in the xenograft tumor mouse model. CONCLUSION: EChLESs enhances cell apoptosis through mitochondrial dysfunction and ferroptosis through NCOA4-mediated ferritinophagy. Thus, Eupatorium chinense L. could be a potential TCM for treating HCC.

Design, synthesis, and biological evaluation of C-8 modified curcumol derivatives against colorectal cancer cell lines.

A series of structurally modified curcumol derivatives at C-8 position were designed and synthesized, whose structures were confirmed by 1H NMR,13C NMR, and HRMS analysis. The tested compounds were evaluated for in vitro antitumor activity against colorectal cancer cell lines SW620, HCT116, and CaCo2. Many of the tested candidates exhibited higher inhibition efficiency than curcumol. Among them, compound 3 l shows the best inhibitory effect on the viability of SW620 with IC50 value of 19.90 ± 0.64 µM. The structure-activity relationships of these derivatives were discussed, which showed that the introduction of amino or aryl groups tended to increase the anti-cancer activity. In addition, compound 3 l may inhibit cancer cell proliferation through triggering cell apoptosis.

Innate and adaptive immune escape mechanisms of hepatitis B virus.

Chronic hepatitis B virus (HBV) infection is an international health problem with extremely high mortality and morbidity rates. Although current clinical chronic hepatitis B (CHB) treatment strategies can partly inhibit and eliminate HBV, viral breakthrough may result due to non-adherence to treatment, the emergence of viral resistance, and a long treatment cycle. Persistent CHB infection arises as a consequence of complex interactions between the virus and the host innate and adaptive immune systems. Therefore, understanding the immune escape mechanisms involved in persistent HBV infection is important for designing novel CHB treatment strategies to clear HBV and achieve long-lasting immune control. This review details the immunological and biological characteristics and escape mechanisms of HBV and the novel immune-based therapies that are currently used for treating HBV.

Design, synthesis, and anticancer activity evaluation of curcumol derivatives.

A new series of C-14 curcumol derivatives as potent anticancer agents were designed and synthesized by click reaction, whose structures were confirmed by 1H NMR,13C NMR, and HRMS analysis. All the synthesized compounds were evaluated for in vitro antitumor activity against colorectal cancer cell lines SW620 and HCT116. Most of them exhibited higher inhibitory activity than curcumol. Especially, compound 3j shows good inhibitory activity against SW620 with IC50 value of 8.10 ± 0.13 µM. The structure-activity relationships (SARs) of these derivatives were discussed. In addition, flow cytometry revealed that compound 3j induced SW620 cells apoptosis by facilitating apoptosis-related proteins expressions. Our findings suggested that fluorine functional group on phenyl ring tended to increase the anticancer activity.

Fasudil prevents liver fibrosis via activating natural killer cells and suppressing hepatic stellate cells.

BACKGROUND: Fasudil, as a Ras homology family member A (RhoA) kinase inhibitor, is used to improve brain microcirculation and promote nerve regeneration clinically. Increasing evidence shows that Rho-kinase inhibition could improve liver fibrosis. AIM: To evaluate the anti-fibrotic effects of Fasudil in a mouse model of liver fibrosis induced by thioacetamide (TAA). METHODS: C57BL/6 mice were administered TAA once every 3 d for 12 times. At 1 wk after induction with TAA, Fasudil was intraperitoneally injected once a day for 3 wk, followed by hematoxylin and eosin staining, sirius red staining, western blotting, and quantitative polymerase chain reaction (qPCR), and immune cell activation was assayed by fluorescence-activated cell sorting. Furthermore, the effects of Fasudil on hepatic stellate cells and natural killer (NK) cells were assayed in vitro. RESULTS: First, we found that TAA-induced liver injury was protected, and the positive area of sirius red staining and type I collagen deposition were significantly decreased by Fasudil treatment. Furthermore, western blot and qPCR assays showed that the levels of alpha smooth muscle actin (α-SMA), matrix metalloproteinase 2 (MMP-2), MMP-9, and transforming growth factor beta 1 (TGF-ß1) were inhibited by Fasudil. Moreover, flow cytometry analysis revealed that NK cells were activated by Fasudil treatment in vivo and in vitro. Furthermore, Fasudil directly promoted the apoptosis and inhibited the proliferation of hepatic stellate cells by decreasing α-SMA and TGF-ß1. CONCLUSION: Fasudil inhibits liver fibrosis by activating NK cells and blocking hepatic stellate cell activation, thereby providing a feasible solution for the clinical treatment of liver fibrosis.

Structural diversities in centrosymmetric La8S4Cl8La12S8Cl4[SbS3]8 and non-centrosymmetric Ln12S8Cl8[SbS3]4 (Ln = La and Ce): syntheses, crystal and electronic structures, and optical properties.

Three thioantimonides charge compensated by Ln/S/Cl cationic layers, namely, La8S4Cl8La12S8Cl4[SbS3]8 and Ln12S8Cl8[SbS3]4 (Ln = La and Ce), have been discovered by conventional solid-state reactions. The former crystallizes in the centrosymmetric space group Pbcm (no. 57), while the latter adopts the polar non-centrosymmetric space group Cc (no. 9). Both of them contain isolated SbS3 trigonal-pyramidal units, which are connected either with the alternating centric [La8S4Cl8]8+ and mirror-symmetric [La12S8Cl4]16+ cationic layers perpendicular to the [001] direction in La8S4Cl8La12S8Cl4[SbS3]8 or with the acentric [Ln12S8Cl8]12+ cationic layers perpendicular to the [100] direction in Ln12S8Cl8[SbS3]4. Interestingly, the discrete SbS3 trigonal pyramids pack in a centrosymmetric and non-centrosymmetric fashion in La8S4Cl8La12S8Cl4[SbS3]8 and La12S8Cl8[SbS3]4, respectively, which can be ascribed to the different compositions and packing fashions in Ln/S/Cl cationic layers. In addition, optical gaps of 2.31 and 2.60 eV for La12S8Cl8[SbS3]4 and La8S4Cl8La12S8Cl4[SbS3]8, respectively, were determined by UV/vis reflectance spectroscopy, showing a blue shift with respect to La7Sb9S24, which can be attributed to the greater contributions of La to the bottom of the CB as confirmed by the DFT study.

L1CAM is involved in lymph node metastasis via ERK1/2 signaling in colorectal cancer.

L1-cell adhesion molecule (L1CAM, L1) belongs to the immunoglobulin superfamily and was originally found to play a role in nerve cells. Recently, the expression and prognostic value of L1 has been established in several cancers, including colorectal cancer (CRC). However, its association with lymph node metastasis in CRC and the mechanisms underlying its effects remain unclear. In this study, we evaluated the L1 transcript levels in CRC (n=12) and normal intestinal tissues (n=15) by qRT-PCR. Western blotting was used to evaluate L1 and pERK1/2 expression levels. Immunohistochemistry was performed to evaluate the relationship between L1 and pERK1/2 in CRC tissues with different levels of differentiation. The mRNA expression levels in CRC tissues were significantly higher compared to normal intestinal tissues. Western blotting demonstrated that both L1 and pERK1/2 levels were higher in CRC than in normal tissues. Immunohistochemistry confirmed that L1 and pERK1/2 levels in adenomas with lymph node metastasis were significantly higher than in poorly and well-differentiated adenomas, indicating that L1 and pERK1/2 levels correlated with CRC lymph node metastasis. In conclusion, L1 and pERK1/2 were significantly up-regulated in CRC tissues and lymph node metastasis may occur via the L1CAM-mediated ERK pathway in CRC.

Poly I:C-based rHBVvac therapeutic vaccine eliminates HBV via generation of HBV-specific CD8+ effector memory T cells.

OBJECTIVE: Chronic hepatitis B (CHB) virus infection is a global health problem. Finding a cure for CHB remains a challenging task. DESIGN: In this study, poly I:C was employed as an adjuvant for HBV therapeutic vaccine (referred to as pHBV-vaccine) and the feasibility and efficiency of pHBV-vaccine in CHB treatment were evaluated in HBV-carrier mice. RESULTS: We found that pHBV-vaccine decreased HBsAg and HBV DNA efficiently and safely in HBV-carrier mice. Further investigation showed that pHBV-vaccine promoted maturation and antigen presentation ability of dendritic cells in vivo and in vitro. This vaccine successfully restored the exhaustion of antigen-specific CD8+ T cells and partly broke the immune tolerance established in HBV-carrier mice. pHBV-vaccine also enhanced the proliferation and polyfunctionality of HBV-specific CD11ahi CD8αlo cells. Importantly, we observed that T cell activation molecule KLRG1 was only expressed on HBV specific CD11ahi CD8αlo cells. Furthermore, pHBV-vaccine reduced the expression of Eomes and increased the serum IL-12 levels, which in turn promoted the generation of effector memory short-lived effector cells (SLECs) to exhibit a critical role in HBV clearance. SLECs induced by pHBV-vaccine might play a crucial role in protecting from HBV reinfection. CONCLUSIONS: Findings from this study provide a new basis for the development of therapeutic pHBV-vaccine, which might be a potential candidate for clinical CHB therapy.

Precise discovery of a STAT3 inhibitor from Eupatorium lindleyanum and evaluation of its activity of anti-triple-negative breast cancer.

Michael reaction acceptors (MRAs) are a class of active compounds. There is a great prospect to screen STAT3 inhibitors from Eupatorium lindleyanum, furthermore, to discover lead compounds for anti-triple-negative breast cancer (TNBC). In this study, glutathione (GSH) was employed, and a UPLC-MS screening method was developed to discover MRAs. We screened MRAs which can inhibit STAT3 using a STAT3-dependent reporter system. Six sesquiterpene lactones, including a new compound Eupalinolide O (1), together with five known compounds, Eupalinolide I (2), Eupalinolide K (3), Eupalinolide H (4), Eupalinolide J (5) and Eupalinolide G (6) were isolated. Eupalinolide J was identified as MRA that decreased luciferase activity of STAT3. Preliminary activity assessment showed that Eupalinolide J could inhibit the viability of TNBC cell lines. We demonstrated that Eupalinolide J, which is a natural typical MRA, has a notable inhibition of STAT3 activity and a potential cytotoxic activity against TNBC cell lines.

Polysaccharide from Phellinus Igniarius activates TLR4-mediated signaling pathways in macrophages and shows immune adjuvant activity in mice.

Polysaccharide from Phellinus igniarius (PPI) is known for its immune-regulating effect with low toxicity. Toll like receptor 4 (TLR4) is important in both innate and adaptive immune responses and considered to be a promising target for new immune adjuvants. In this study, PPI was investigated for its effect on activating TLR4 in RAW264.7 and peritoneal macrophages. The adjuvant potential of PPI was evaluated in OVA-immunized mice. The results showed PPI treatment significantly increased the secretion and the mRNA expression of both MyD88 dependent and TRIF dependent cytokines. IRAK-1, a key molecule on the downstream of MyD88, was polyubiquitinated while IRF-3, another key molecule on the downstream of TRIF, was phosphorylated obviously after the treatment of PPI. The phosphorylation of molecules involved in both NF-κB pathway and MAPK pathway were significantly up-regulated after PPI treatment. In addition, the effects of PPI on the macrophages almost completely disappeared after treating the cells with the TLR4 antagonist TAK-242. Further in vivo results showed PPI significantly increased the serum OVA-specific antibody and the OVA-specific spleen cell proliferation. Taken together, PPI can specifically stimulate TLR4 and activate both MyD88 and TRIF pathways. PPI has immune adjuvant activity and may become a new potential immune adjuvant.

A new five-coordinated copper compound for efficient degradation of methyl orange and Congo red in the absence of UV-visible radiation.

A new copper-based coordination compound Cu2(2,2'-bipy)2(pfbz)4 (1) (where 2,2'-bipy = 2,2'-bipyridine; pfbz = pentafluorobenzoate), was hydrothermally synthesized and structurally characterized. Compound 1 having a binuclear structure consists of two copper cations and two oxygen atoms alternately in a plane square arrangement. In the presence of very small amounts of H2O2, the catalytic properties of compound 1 for the degradation of methyl orange (MO) are excellent in the absence of UV-visible radiation. Moreover, compound 1 presents suitable properties for degradation of Congo red (CR). Our results indicated that the five-coordinated copper compound, 1, will be a promising candidate for efficient degradation of organic dyes.

The Loss of a Sugar Chain at C(3) Position Enhances Stemucronatoside K-Induced Apoptosis, Cell Cycle Arrest, and Hedgehog Pathway Inhibition in HT-29 Cells.

Stemucronatoside K (SMK) and its aglycone stephanthraniline A (STA) are the most representative of a series of novel C21 steriodal compounds that we have previously isolated from Asclepiadaceae plants. The objectives of this study were to investigate the antitumor activity of SMK and STA, and clarify the effect of the sugar chain at the C(3) position. Our results showed that both SMK and STA decreased the growth of HT-29 cells in a dose- and time-dependent manner. Meanwhile, STA showed much stronger inhibitory effect than SMK. Treatment of HT-29 cells with STA increased the apoptotic cell numbers and the protein expression of cleaved caspase 3 and cleaved-PARP. G1 phase cell cycle arrest and decreased expression of cyclin D1 and cyclin-dependent kinases 4 were also observed after STA treatment. Furthermore, STA reduced the mRNA levels of four Hedgehog pathway components (GLI1, GLI2, GLI3, and PTCH1) and suppressed Shh-induced Hedgehog pathway activation in a concentration-dependent manner. These results indicated that SMK and STA could inhibit the growth of HT-29 cells by inducing apoptosis, cell cycle arrest, and hedgehog pathway inhibition. The loss of sugar chain at C(3) position could enhance SMK's activity. This study is beneficial to understand the use of natural C21 steroids as antitumor lead compounds.

Pb5Ga6ZnS15: a noncentrosymmetric framework with chains of T2-supertetrahedra.

A novel noncentrosysmmetric sulfide, Pb5Ga6ZnS15 (1), was synthesized for the first time. Its crystal structure revealed the presence of [GaS2](-)∞ (chain 1, chains of [GaS4](5-) tetrahedra) and [Ga4S9](6-)∞ (chain 2, chains of T2-supertetrahedra) connected by isolated [ZnS4](6-) tetrahedra. Structure correlation with the network constructed solely using chain 1 (Pb4Ga4GeQ12-type) is discussed. Pb5Ga6ZnS15 was calculated to have a suitable static briefringence (Δn) of 0.1137, and a large nonlinear optical susceptibility d31 of 58.32 pm V(-1) at a wavelength of 2.05 µm (0.6 eV), much higher than that of the benchmark AgGaS2 (18.14 pm V(-1)).

Strong Infrared NLO Tellurides with Multifunction: CsX(II)4In5Te12 (X(II) = Mn, Zn, Cd).

Chalcogenides are the most promising mid- and far-infrared materials for nonlinear optical (NLO) applications. Yet, most of them are sulfides and selenides, and tellurides are still rare. Herein, we report three new KCd4Ga5S12-structure type NLO-active tellurides, CsX(II)4In5Te12 (X(II) = Mn, Zn, Cd), synthesized by solid-state reactions. The structure features a 3D diamond-like framework constructed by vertex-sharing asymmetric MTe4 tetrahedra that are stacked along the c-axis. CsCd4In5Te12 exhibits the strongest powder second-harmonic generation (SHG) intensity at 2050 nm (0.61 eV) among tellurides to date, 9 × benchmark AgGaS2 in the range of 46-74 µm particle size. The primary studies reveal the 1.42 eV direct band gap and high absorption coefficient in the visible spectral region for CsCd4In5Te12, suggesting it is a new potential solar cell absorber material. In addition, CsMn4In5Te12 also displays a spin-canted antiferromagnetic property below 50 K.

(Cs6Cl)6Cs3[Ga53Se96]: A Unique Long Period-Stacking Structure of Layers Made from Ga2Se6 Dimers via Cis or Trans Intralayer Linking.

The new compound (Cs6Cl)6Cs3[Ga53Se96] with its own structure type has been discovered by high-temperature solid-state reactions. The compound features a unique long period-stacking structure of layers that are built by the commonly observed dimeric Ga2Se6 unit extending in cis or trans intralayer linking. Single-crystal X-ray diffraction analyses show the trigonal space group R3̅m (No. 166) and a = 11.990(5) Å, c = 50.012(4) Å, and V = 6226.5(6) Å(3). The UV-vis-near-IR spectrum reveals a wide band gap of 2.74 eV that agrees well with the electronic structure calculation.

Combined inhibition of EGFR and c-ABL suppresses the growth of triple-negative breast cancer growth through inhibition of HOTAIR.

Triple-negative breast cancer (TNBC) does not express conventional therapeutic targets and is the only type of malignant breast cancer for which no designated FDA-approved targeted therapy is available. Although overexpression of epidermal growth factor receptor (EGFR) is frequently found in TNBC, the therapeutic effect of EGFR inhibitors in TNBC has been underwhelming. Here we show that co-treatment with clinically validated inhibitors of c-ABL (imatinib) and EGFR (lapatinib) results in synergistic growth inhibition in TNBC cells. The dual treatment leads to synergistic repression of the long non-coding RNA (lncRNA) HOTAIR (HOX Antisense Intergenic RNA). HOTAIR has been known to induce tumor growth and metastasis in breast cancer. Depleting HOTAIR alone phenocopies the dual treatment in growth suppression. We show that expression of HOTAIR is regulated by ß-catenin through a LEF1/TCF4-binding site. The dual treatment blocks nuclear expression of ß-catenin and prevents its recruitment to the HOTAIR promoter. Consistently, forced expression of ß-catenin rescued HOTAIR expression and cell viability in the presence of both drugs. Upregulation of HOTAIR is associated with TNBC in cell lines and a cohort of primary tumors. This study elucidates a previously unidentified mechanism in TNBC linking signaling with lncRNA regulation which may be exploited for therapeutic gain.

Strong Kleinman-forbidden second harmonic generation in chiral sulfide: La4InSbS9.

A new chiral sulfide family, Ln(4)InSbS(9) (Ln = La, Pr, Nd), with its own structure type in space group P4(1)2(1)2 or its enantiomorph P4(3)2(1)2 has been synthesized by solid-state reaction. Remarkably, the La member shows the strongest Kleinman-forbidden second harmonic generation to date, with an intensity 1.5 times that of commercial AgGaS(2) at a laser wavelength of 2.05 µm, and exhibits type-I phase-matchable behavior. Density functional theory calculations and ab initio molecular dynamics simulations suggest that lattice vibrations may be responsible for the origin and magnitude of the strong SHG effect.