Design, synthesis, and anti-tumor activity of derivatives of ring A and C-28 of asiatic acid

Based on computer-aided drug design (CADD), the active groups of the known active small molecule compounds that can bind to EGFR target protein were analyzed through the molecular docking method. Then, 12 novel asiatic acid derivatives were synthesized by introducing active groups at ring A and C-28 positions of asiatic acid. The structures of these novel compounds were determined by NMR and MS. Furthermore, the anti-tumor activities of these derivatives on human lung cancer cells (A549) and human breast cancer cells (MCF-7) were evaluated by MTT assay. In conclusion, compounds I4 and II3 have stronger anti-cancer activity than parent compounds, the activities were stronger than gefitinib and comparable to afatinib, which may be potential candidate compounds for tumor therapy.

Enhanced Anti-tumor Effect of Flavopiridol in Combination With Gemcitabine in Pancreatic Cancer

BACKGROUND/AIM

The efficacy of current chemotherapies for pancreatic ductal adenocarcinoma (PDAC) is still unsatisfactory. Flavopiridol inhibits multiple cyclin-dependent kinases, causing cell cycle arrest and inducing cancer cell apoptosis. This study aimed to evaluate the anti-tumor effect of flavopiridol and gemcitabine in PDAC in vitro and in vivo.

MATERIALS AND METHODS

PANC-1 and MIA PaCa-2 cell lines were treated with gemcitabine and flavopiridol alone, in combination, and sequentially, and cell proliferation, apoptosis, and the cell cycle were evaluated. Proteins related to cell cycle progression (cyclin A, CDK2, E2F-1, and p53) were quantified using western blotting. A xenograft mouse model was generated, and the effects of gemcitabine and flavopiridol, administered alone or in combination, were evaluated by measuring tumor volume and apoptosis degree using the TUNEL assay.

RESULTS

Sequential administration of gemcitabine and flavopiridol suppressed PDAC cell proliferation and induced apoptosis. Flavopiridol treatment led to an increase in the number of cells in the S and a decrease in those in the G0/G1 phases. Gemcitabine increased and decreased the number of S- and G2/M-phase cells, respectively. Furthermore, flavopiridol treatment decreased cyclin A and CDK2 expression and increased E2F-1 expression. In a xenograft mouse model, the combined administration of gemcitabine and flavopiridol demonstrated the most significant reduction in tumor volume and induction of apoptosis.

CONCLUSION

Flavopiridol potentiates the anti-tumor activity of gemcitabine by inducing cell cycle arrest and apoptosis. Its synergistic inhibition of PDAC cell proliferation, when combined with gemcitabine, positions flavopiridol as a promising candidate for cancer treatment.

C6 Ceramide Inhibits Canine Mammary Cancer Growth and Metastasis by Targeting EGR3 through JAK1/STAT3 Signaling

Cancer is the leading cause of death in both humans and companion animals. Canine mammary tumor is an important disease with a high incidence and metastasis rate, and its poor prognosis remains a serious clinical challenge. C6 ceramide is a short-chain sphingolipid metabolite with powerful potential as a tumor suppressor. However, the specific impact of C6 ceramide on canine mammary cancer remains unclear. However, the effects of C6 ceramide in canine mammary cancer are still unclear. Therefore, we investigated the role of C6 ceramide in the progress of canine mammary cancer and explored its potential mechanism. C6 ceramide inhibited cell growth by regulating the cell cycle without involving apoptosis. Additionally, C6 ceramide inhibited the migration and invasion of CHMp cells. In vivo, C6 ceramide decreased tumor growth and metastasis in the lungs without side effects. Further investigation found that the knockdown of EGR3 expression led to a noticeable increase in proliferation and migration by upregulating the expressions of pJAK1 and pSTAT3, thus activating the JAK1/STAT3 signaling pathway. In conclusion, C6 ceramide inhibits canine mammary cancer growth and metastasis by targeting EGR3 through the regulation of the JAK1/STAT3 signaling pathway. This study implicates the mechanisms underlying the anti-tumor activity of C6 ceramide and demonstrates the potential of EGR3 as a novel target for treating canine mammary cancer.

Curcumin Inhibits the Growth of Hepatocellular Carcinoma via the MARCH1-mediated Modulation of JAK2/STAT3 Signaling

BACKGROUND

Curcumin has been reported to have anti-hepatocellular carcinoma (HCC) effects, but the underlying mechanism is not well known.

OBJECTIVES

To investigate whether membrane-associated RING-CH 1 (MARCH1) is involved in the curcumin-induced growth suppression in HCC and its underlying molecular mechanism. A few recent patents for curcumin for cancer are also reviewed in this article.

METHODS

The effect of curcumin on growth inhibition of HCC cells was analyzed through in vitro and in vivo experiments, and the expression levels of MARCH1, Bcl-2, VEGF, cyclin B1, cyclin D1, and JAK2/STAT3 signaling molecules were measured in HCC cells and the xenograft tumors in nude mice. Cell transfection with MARCH1 siRNAs or expression plasmid was used to explore the role of MARCH1 in the curcumin-induced growth inhibition of HCC cells.

RESULTS

Curcumin inhibited cell proliferation, promoted apoptosis, and arrested the cell cycle at the G2/M phase in HCC cells with the decrease of Bcl-2, VEGF, cyclin B1, and cyclin D1 expression as well as JAK2 and STAT3 phosphorylation, resulting in the growth suppression of HCC cells. MARCH1 is highly expressed in HCC cells, and its expression was downregulated after curcumin treatment in a dose-dependent manner. The knockdown of MARCH1 by siRNA decreased the phosphorylation levels of JAK2 and STAT3 and inhibited the growth of HCC cells. In contrast, opposite results were observed when HCC cells overexpressed MARCH1. A xenograft tumor model in nude mice also showed that curcumin downregulated MARCH1 expression and decelerated the growth of transplanted HCC with the downregulation of JAK2/STAT3 signaling and functional molecules. The ADC value of MRI analysis showed that curcumin slowed down the progression of HCC.

CONCLUSION

Our results demonstrated that curcumin may inhibit the activation of JAK2/STAT3 signaling pathway by downregulating MARCH1 expression, resulting in the growth suppression of HCC. MARCH1 may be a novel target of curcumin in HCC treatment.

Enhanced anti-tumor activity of arginine decarboxylase through the incorporation of aromatic amino acids at the multimer-forming interface

The pressing challenge of cancer's high mortality and invasiveness demands improved therapeutic approaches. Targeting the nutrient dependencies within cancer cells has emerged as a promising approach. This study is dedicated to demonstrating the potential of arginine depletion for cancer treatment. Notably, the focus centers on arginine decarboxylase (RDC), a pH-dependent enzyme expecting enhanced activity within the slightly acidic microenvironments of tumors. To investigate the effect of a single-site mutation on the catalytic efficacy of RDC, diverse amino acids, including glycine, alanine, phenylalanine, tyrosine, tryptophan, p-azido-phenylalanine, and a phenylalanine analog with a hydrogen-substituted tetrazine, were introduced at the crucial threonine site (position 39) in the multimer-forming interface. Remarkably, the introduction of either a natural or a non-natural aromatic amino acid at position 39 substantially boosted enzymatic activity, while amino acids with smaller side chains did not show the same effect. This enhanced enzymatic activity is likely attributed to the reinforced formation of multimer structures through favorable interactions between the introduced aromatic amino acid and the neighboring subunit. Noteworthy, at slightly acidic pH, the RDC variant featuring tryptophan at position 39 demonstrated augmented cytotoxicity against tumor cells compared to the wild-type RDC. This attribute aligns with the tumor microenvironment and positions these variants as potential candidates for targeted cancer therapy.

Chemical constituents from the stem of Ficus pumila

A new biphenyl compound: 5-aldehyde-4'-hydroxy-2,2'-dimethoxybiphenyl (1), along with 11 known phenolic compounds (2-12) were isolated from the stem of Ficus pumila Linn. Their structures were established by spectroscopic methods, including MS, UV, IR, 1 D and 2 D NMR. Compounds 4 and 10 showed weakly cytotoxicity against MCF-7, with IC50 values of 32.5 and 37.3 µM, respectively.

Ribosome-inactivating Protein MAP30 Isolated from Momordica Charantia L. Induces Apoptosis in Hepatocellular Carcinoma Cells

BACKGROUND

Ribosome-inactivating proteins (RIPs) have been reported to exert antitumor and anti-virus activities. A recent patent CN202011568116.7 has developed a new method to prepare Momordica anti-HIV protein of 30 kDa (MAP30). MAP30 is a type I RIP, which kills various tumor cells through the N-glycosidase activity and irreversibly inhibits protein synthesis.

OBJECTIVE

To assess the potential role of MAP30 in inducing apoptosis of human hepatocellular carcinoma HCC-LM3 cells and elucidate the molecular mechanism of MAP30.

METHODS

CCK-8 assay was used to assess the proliferation of HCC-LM3 cells. Flow cytometry was used to measure the cycle, the level of ROS and apoptosis in HCC-LM3 cells. Western blots was used to measure protein levels.

RESULTS

Treatment with MAP30 reduced survival and proliferation of human liver cancer HCCLM3 cells in a dose-dependent manner. PI staining showed cell cycle arrest in G0/G1 phase. Furthermore, MAP30 increased the level of ROS in HCC-LM3 cells in 24 h treatment. To further confirm the role of MAP30 in inducing cell apoptosis, immunoblotting was carried out to detect the change of apoptosis-related proteins including PARP poly (ADP-ribose) polymerase (PARP- 1), Casepase3 and Cleaved-Caspase9. We found that PARP-1 and Caspase-3 were downregulated, whereas Cleaved-Caspase9 was up-regulated in HCC-LM3 cells treated with MAP30.

CONCLUSION

This study indicated that MAP30 has the potential to be a novel therapeutic agent for human hepatocellular carcinoma.

Synthesis and anti-tumor activity of asiatic acid derivatives targeting VEGFR

To discovery novel VEGFR inhibitors, 12 novel asiatic acid derivatives were designed by computer-aided drug design (CADD) technology. Then, these novel asiatic acid derivatives were synthesized by introducing active groups at ring A and C-28 positions of asiatic acid. The structures of these novel analogues were confirmed by NMR and MS. Moreover, the anti-tumor activities of these novel asiatic acid derivatives on human hepatoma cells HepG2 and human gastric cancer cells SGC7901 were evaluated by MTT assay. As a result, compounds I2 and II4 showed stronger cytotoxicity on tumor cells than asiatic acid and positive control drugs such as gefitinib and paclitaxel. In conclusion, our study synthesized twelve novel asiatic acid derivatives and determined compounds I2 and II4 had better anti-tumor effect which may be potential candidate compounds for tumor therapy.

Total syntheses of pongaflavone and its natural analogues

The efficient total synthesis of anti-tumor natural product pongaflavone (1) was described starting from commercially available 2,4-dihydroxyacetophenone (9) via seven steps and in 16% overall yield. Its two natural analogues pongachromene (2) and 7,8-(2",2"-dimethylpyrano)-5,3',4'-trihydroxy-3-methoxyflavone (3) were also synthesized following the similar procedure with the yields of 11% and 18%, respectively. Their preliminary anti-tumor activities were evaluated by the inhibition effect on A549 cells. The result showed that this kind of natural products exhibited different levels of anti-tumor activity. Among them, pongachromene (2) displayed the best anti-tumor activity.

Coumarins from Jinhua Finger Citron: Separation by Liquid-Liquid Chromatography and Potential Antitumor Activity

In this paper, liquid-liquid chromatography was introduced for the first time for the separation of fingered citron (Citrus medica L. var. sarcodactylis Swingle). The fingered citron cultivated in Jinhua is of significant industrial and medicinal value, with several major coumarin compounds detected in its extract. Therefore, further separation for higher purity was of necessity. A preparative liquid-liquid chromatographic method was developed by combining two elution modes (isocratic and step-gradient) with selection according to different polarities of the target sample. Five coumarin derivatives-5,7-dimethoxycoumarin (52.6 mg, 99.6%), phellopterin (4.9 mg, 97.1%), 5-prenyloxy-7-methoxycoumarin (6.7 mg, 98.7%), 6-hydroxy-7-methoxycoumarin (7.1 mg, 82.2%), and byakangelicol (10.5 mg, 90.1%)-with similar structures and properties were isolated on a large scale from 100 mg of petroleum ether (PE) extract and 100 mg of ethyl acetate (EA) extract in Jinhua fingered citron. The productivity was much improved. The anti-growth activity of the isolated coumarins was evaluated against three cancer cell lines (HeLa, A549, and MCF7) with an MTT assay. The coumarins demonstrated potential anti-tumor activity on the HeLa cell line, with 5,7-dimethoxycoumarin in particular exhibiting the best anti-growth activity (IC50 = 10.57 ± 0.24 μM) by inhibiting proliferation. It inhibited colony formation and reduced the size of the tumor sphere in a concentration-dependent manner. The main mechanism was confirmed as inducing apoptosis. This work was informative for further studies aimed at exploring new natural-product-based antitumor agents.

Efficacy and safety of zanubrutinib plus R-CHOP in treatment of non-GCB DLBCL with extranodal involvement

Introduction

Treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) shows poor response rates in non-germinal center B cell-like (non-GCB) diffuse large B-cell lymphoma (DLBCL) patients with multiple extranodal involvement. This study aims to evaluate anti-tumor activity and safety of zanubrutinib with R-CHOP (ZR-CHOP) in treatment naïve non-GCB DLBCL with extranodal involvement.

Methods

In this single-arm, phase 2, prospective, single-center study, patients with newly diagnosed non-GCB DLBCL with extranodal involvement enrolled between October 2020 to March 2022 received ZR-CHOP for 6 cycles followed by 2 cycles of maintenance treatment with rituximab and zanubrutinib. The primary endpoint included progression-free survival (PFS) in the intent-to-treat (ITT) population whereas the secondary endpoints included overall response rate (ORR), complete response (CR), and duration of response. Further, next-generation sequencing (NGS) was used for detection of different oncogenic mutations closely related to DLBCL pathogenesis.

Results

From October 2020 to March 2022, 26 patients were enrolled, and 23 of them were evaluated for efficacy after receiving 3 cycles of ZR-CHOP treatment. 1-year PFS and OS were 80.8% and 88.5% respectively while expected PFS and OS for 2-years are 74.0% and 88.5% respectively with median follow-up of 16.7 months and ORR was 91.3% (CR: 82.61%; PR: 8.70%). Oncogenic mutations closely related to DLBCL pathogenesis were assessed in 20 patients using NGS. B-cell receptor and NF-κB pathway gene mutations were detected in 10 patients, which occurred in MYD88 (7/19), CD79B (4/19), CARD11 (5/19), and TNFAIP3 (2/19). Hematological adverse events (AEs) ≥ grade 3 included neutropenia (50%), thrombocytopenia (23.1%), and anemia (7.7%) whereas non-hematological AEs ≥ grade 3 included pulmonary infection (19.2%).

Conclusion

ZR-CHOP is safe and effective for treating treatment naïve non-GCB DLBCL patients with extranodal involvement.

Clinical Trial Registration

Clinicaltrials.gov, NCT04835870.

A Novel Betulinic Acid Analogue: Synthesis, Solubility, Antitumor Activity and Pharmacokinetic Study in Rats

Betulinic acid (BA) and betulin (BE) are naturally pentacyclic triterpenes with documented biological activities, especially antitumor and anti-inflammatory activity. However, their bioavailability in vivo is not satisfactory in terms of medical applications. Thus, to improve the solubility and bioavailability so as to improve the efficacy, 28-O-succinyl betulin (SBE), a succinyl derivative of BE, was synthesized and its solubility, in vitro and in vivo anti-tumor activities, the apoptosis pathway as well as the pharmacokinetic properties were investigated. The results showed that SBE exhibited significantly higher solubility in most of the tested solvents, and showed a maximum solubility of 7.19 ± 0.66 g/L in n-butanol. In vitro and in vivo anti-tumor activity assays indicated both BA and SBE exhibited good anti-tumor activities, and SBE demonstrated better potential compared to BA. An increase in the ratio of Bad/Bcl-xL and activation of caspase 9 was found in SBE treated Hela cells, suggesting that the intrinsic mitochondrial pathway is involved in SBE induced apoptosis. Compared with BA, SBE showed much-improved absorption and bioavailability in pharmacokinetic studies.

CD73 Dysregulates Monocyte Anti-Tumor Activity in Multiple Myeloma

Purpose

Multiple myeloma (MM) is characterized by immune cell dysfunction in the tumor microenvironment (TME). We aimed at evaluating the effect of CD73, an overexpressed factor in some tumors, on anti-tumor immune function in the TME of MM.

Patients and Methods

We analyzed the expression of CD73 in T-, B-, and natural killer (NK)-lymphocytes and monocytes in bone marrow (BM), peripheral blood (PB) from MM patients and healthy controls, and residual CD138+ cells using flow cytometry. The anti-tumor activity of these monocytes was confirmed by co-culture with RPMI-8226 cells treated with a CD73 inhibitor. We determined the interleukin (IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ levels using a cytometric bead array. Monocyte phagocytosis in cell culture sediment was then observed and measured.

Results

CD73 was highly expressed in T-, B-, and NK-lymphocytes and monocytes from the BM and PB isolated from patients with MM. Compared with healthy controls, MM samples exhibited significantly higher CD73 expression and TNF-α, IFN-γ, IL-10 levels in monocytes. Inhibiting CD73 in BM immune cells from MM samples significantly increased the secretion of IL-2, TNF-α, and IFN-γ, as well as the killing ability of immune cells. However, monocyte phagocytosis was seldom observed. Inhibiting CD73 in MM monocytes significantly increased the secretion of IL-2, TNF-α, and IFN-γ in monocytes and improved monocyte killing and phagocytosis.

Conclusion

Monocytes from MM exhibited weakened anti-tumor effects, and CD73 was involved in forming an immunosuppressive microenvironment. Inhibiting CD73 partly restored the anti-tumor activity of monocytes, a potential strategy for the treatment of MM.

Comparative Analysis of Water-Soluble Polysaccharides from Dendrobium Second Love 'Tokimeki' and Dendrobium nobile in Structure, Antioxidant, and Anti-Tumor Activity In Vitro

With potential anti-tumor and antioxidant properties, the polysaccharide content of D. nobile is relatively lower than that of the other medicinal Dendrobium. To find high-content polysaccharide resources, the polysaccharide (DHPP-Ⅰs) was prepared from D. Second Love 'Tokimeki' (a D. nobile hybrid) and compared with DNPP-Ⅰs from D. nobile. DHPP-Is (Mn 31.09 kDa) and DNPP-Is (Mn 46.65 kDa) were found to be O-acetylated glucomannans (-Glcp-(1,4) and O-acetylated-D-Manp-(1,4) backbones), analogous to other Dendrobium polysaccharides. DHPP-Ⅰs had higher glucose content (31.1%) and a lower degree (0.16) of acetylation than DNPP-Ⅰs (15.8%, 0.28). Meanwhile, DHPP-Ⅰs and DNPP-Ⅰs had the same ability in the radical scavenging assay, which was milder than the control of Vc. Both DHPP-Is and DNPP-Is inhibited SPC-A-1 cell proliferation in vitro, with obvious differences in dose concentrations (0.5-2.0 mg/mL) and treatment times (24-72 h). Therefore, the antioxidant activity of DHPP-Ⅰs and DNPP-Ⅰs is not associated with distinction in anti-proliferative activity. As a glucomannan derived from non-medicinal Dendrobium, DHPP-Ⅰs has similar bioactivity to other medicinal Dendrobium, and this could serve as a starting point for studying the conformational-bioactivity relationship of Dendrobium polysaccharides.

[Research progress on chemical structures and pharmacological effects of natural cytisine and its derivatives]

Cytisine derivatives are a group of alkaloids containing the structural core of cytisine, which are mainly distributed in Fabaceae plants with a wide range of pharmacological activities, such as resisting inflammation, tumors, and viruses, and affecting the central nervous system. At present, a total of 193 natural cytisine and its derivatives have been reported, all of which are derived from L-lysine. In this study, natural cytisine derivatives were classified into eight types, namely cytisine type, sparteine type, albine type, angustifoline type, camoensidine type, cytisine-like type, tsukushinamine type, and lupanacosmine type. This study reviewed the research progress on the structures, plant sources, biosynthesis, and pharmacological activities of alkaloids of various types.

Preparation and Anti-Lung Cancer Activity Analysis of Guaiacyl-Type Dehydrogenation Polymer

In this paper, guaiacyl dehydrogenated lignin polymer (G-DHP) was synthesized using coniferin as a substrate in the presence of β-glucosidase and laccase. Carbon-13 nuclear magnetic resonance (¹³C-NMR) determination revealed that the structure of G-DHP was relatively similar to that of ginkgo milled wood lignin (MWL), with both containing β-O-4, β-5, β-1, β-β, and 5-5 substructures. G-DHP fractions with different molecular weights were obtained by classification with different polar solvents. The bioactivity assay indicated that the ether-soluble fraction (DC₂) showed the strongest inhibition of A549 lung cancer cells, with an IC₅₀ of 181.46 ± 28.01 μg/mL. The DC₂ fraction was further purified using medium-pressure liquid chromatography. Anti-cancer analysis revealed that the D₄ and D₅ compounds from DC₂ had better anti-tumor activity, with IC₅₀ values of 61.54 ± 17.10 μg/mL and 28.61 ± 8.52 μg/mL, respectively. Heating electrospray ionization tandem mass spectrometry (HESI-MS) results showed that both the D₄ and D₅ were β-5-linked dimers of coniferyl aldehyde, and the ¹³C-NMR and ¹H-NMR analyses confirmed the structure of the D₅. Together, these results indicate that the presence of an aldehyde group on the side chain of the phenylpropane unit of G-DHP enhances its anticancer activity.

The Large Molecular Weight Polysaccharide from Wild Cordyceps and Its Antitumor Activity on H22 Tumor-Bearing Mice

Cordyceps has anti-cancer effects; however, the bioactive substance and its effect are still unclear. Polysaccharides extracted from Cordyceps sinensis, the fugus of Cordyceps, have been reported to have anti-cancer properties. Thus, we speculated that polysaccharides might be the key anti-tumor active ingredients of Cordyceps because of their larger molecular weight than that of polysaccharides in Cordyceps sinensis. In this study, we aimed to investigate the effects of wild Cordyceps polysaccharides on H22 liver cancer and the underlying mechanism. The structural characteristics of the polysaccharides of WCP were analyzed by high-performance liquid chromatography, high-performance gel-permeation chromatography, Fourier transform infrared spectrophotometry, and scanning electron microscopy. Additionally, H22 tumor-bearing BALB/c mice were used to explore the anti-tumor effect of WCP (100 and 300 mg/kg/d). The mechanism by WCP inhibited H22 tumors was uncovered by the TUNEL assay, flow cytometry, hematoxylin-eosin staining, quantitative reverse transcription-polymerase chain reaction, and Western blotting. Here, our results showed that WCP presented high purity with an average molecular weight of 2.1 × 10⁶ Da and 2.19 × 10⁴ Da. WCP was determined to be composed of mannose, glucose, and galactose. Notably, WCP could inhibit the proliferation of H22 tumors not only by improving immune function, but also by promoting the apoptosis of tumor cells, likely through the IL-10/STAT3/Bcl2 and Cyto-c/Caspase8/3 signaling pathways, in H22 tumor-bearing mice. Particularly, WCP had essentially no side effects compared to 5-FU, a common drug used in the treatment of liver cancer. In conclusion, WCP could be a potential anti-tumor product with strong regulatory effects in H22 liver cancer.

Design, synthesis and anti-tumor activity of asiatic acid derivatives as VEGF inhibitors

The VEGF receptor is mock-coupled with a known active compound and the active groups of the inhibitor which can bind to VEGF were analyzed. Using asiatic acid as a lead compound, 10 novel skeleton candidate compounds were designed through introduction of the active groups onto the special location and synthesized simultaneously. Furthermore, the structure of these compounds was determined by ¹H NMR, ¹³C NMR and MS and 9 compounds were identified as the new compounds. Moreover, the in vitro anti-tumor activities of these new compounds were determined by MTT assay on two cancer cell lines (HepG2 and SGC-7901). The results showed that compounds I₁ and II₂ have more potent anticancer activity than positive control drugs such as gefitinib and paclitaxel.

Blockade of ß-Adrenergic Receptors by Nebivolol Enables Tumor Control Potential for Uveal Melanoma in 3D Tumor Spheroids and 2D Cultures

Uveal melanoma (UM) is the most common primary cancer of the eye in adults. A new systemic therapy is needed to reduce the high metastasis and mortality rate. As β-blockers are known to have anti-tumor effects on various cancer entities, this study focuses on investigating the effect of β1-selective blockers atenolol, celiprolol, bisoprolol, metoprolol, esmolol, betaxolol, and in particular, nebivolol on UM. The study was performed on 3D tumor spheroids as well as 2D cell cultures, testing tumor viability, morphological changes, long-term survival, and apoptosis. Flow cytometry revealed the presence of all three β-adrenoceptors with a dominance of β2-receptors on cell surfaces. Among the blockers tested, solely nebivolol concentration-dependently decreased viability and altered 3D tumor spheroid structure. Nebivolol blocked the repopulation of cells spreading from 3D tumor spheroids, indicating a tumor control potential at a concentration of ≥20 µM. Mechanistically, nebivolol induced ATP depletion and caspase-3/7 activity, indicating that mitochondria-dependent signaling is involved. D-nebivolol or nebivolol combined with the β2-antagonist ICI 118.551 displayed the highest anti-tumor effects, suggesting a contribution of both β1- and β2-receptors. Thus, the present study reveals the tumor control potential of nebivolol in UM, which may offer a perspective for co-adjuvant therapy to reduce recurrence or metastasis.

Structurally Diverse Diterpenes from the South China Sea Soft Coral Sarcophyton trocheliophorum

The present investigation of the South China Sea soft coral Sarcophyton trocheliophorum resulted in the discovery of six new polyoxygenated diterpenes, namely sartrocheliols A-E (1, 3, 5-8) along with four known ones, 2, 4, 9, and 10. Based on extensive spectroscopic data analysis, sartrocheliol A (1) was identified as an uncommon capnosane diterpene, while sartrocheliols B-E (3, 5-8) were established as cembrane diterpenes. They displayed diverse structural features not only at the distinctly different carbon frameworks but also at the various types of heterocycles, including the epoxide, γ-lactone, furan, and pyran rings. Moreover, their absolute configurations were determined by a combination of quantum mechanical-nuclear magnetic resonance (QM-NMR) approach, modified Mosher's method, and X-ray diffraction analysis. In the anti-tumor bioassay, compound 4 exhibited moderate cytotoxic activities against A549, H1975, MDA-MB-231, and H1299 cells with the IC₅₀ values ranging from 26.3 to 47.9 μM.

The application basis of immuno-checkpoint inhibitors combined with chemotherapy in cancer treatment

Immuno-checkpoint inhibitors (ICIs) bring a promising prospect for patients with cancers, which restrains the growth of tumor cells by enhancing anti-tumor activity. Nevertheless, not all patients benefit from the administration of ICIs monotherapy. The partial response or resistance to ICIs is mainly due to the complex and heterogenous tumor microenvironment (TME). The combined therapy is necessary for improving the efficacy of tumor treatment. Chemotherapy is reported not only to kill tumor cells directly, but also to stimulate effective anti-tumor immune responses. Several combined therapies of ICIs and chemotherapeutic agents have been approved for the first-line treatment of cancers, including PD-1/PD-L1 inhibitors. This review summarizes the potential mechanisms of the combined therapy of ICIs and chemotherapeutic agents in inducing immunogenic cell death (ICD) and reprogramming TME, and elucidates the possible anti-tumor effects of combined therapy from the perspective of metabolic reprogramming and microbiome reprogramming.

The Silkworm Carboxypeptidase Inhibitor Prevents Gastric Cancer Cells' Proliferation through the EGF/EGFR Signaling Pathway

Gastric cancer is a common malignant tumor originating from the gastric mucosa epithelium. Studies have shown that bioactive substances such as antimicrobial peptides and cantharidin contained in a variety of insects can exert anti-cancer functions; when compared with chemotherapy drugs, these bioactive substances have less toxicity and reduced side effects. Here, we report the first Bombyx mori carboxypeptidase inhibitor that is specifically and highly expressed in silk glands, which can significantly prevent the proliferation of gastric cancer cells by inhibiting the MAPK/ERK pathway initiated by EGF/EGFR through the promotion of expression of the proto-oncogene c-Myc, thereby affecting the expression of related cyclins. Through molecular docking and virtual screening of silkworm carboxypeptidase inhibitors and epidermal growth factor receptors, we identified a polypeptide that overlapped with existing small-molecule inhibitors of the receptor. In the present work, we explore the medicinal potential and application of silkworm carboxypeptidase inhibitors to promote the development of anti-tumor drugs from insect-derived substances.

Research Progress in Elucidating the Mechanisms Underlying Resveratrol Action on Lung Cancer

Resveratrol has several functions, including protection of the heart and nervous system and exerts antidiabetic, anti-inflammatory, anti-aging, and antitumor effects. It is reported to impede the occurrence and development of tumors in cancer cell lines, animal models, and clinical studies. In vitro and in vivo experiments show that it exerts preventive or adjuvant therapeutic effects in pancreatic, colorectal, prostate, liver, and lung cancers. Mechanistic research reports show that resveratrol can induce tumor cell apoptosis and autophagy, inhibit cell cycle and angiogenesis, regulate nuclear factors and cyclooxygenase signal transduction pathways, and inhibit carcinogens' metabolic activation and alter tumor-related expression patterns; anti-oxidation affects tumor cell proliferation, metastasis, and apoptosis. However, the exact mechanism underlying its action remains unclear. This review highlights multiple aspects of the biological impacts and mechanisms underlying resveratrol action on the occurrence and development of lung cancer.

Preparation and Evaluation of Paclitaxel-Loaded PEGylated Niosomes Composed of Sorbitan Esters

Niosomes are non-ionic surfactant (NIS)-based bilayer vesicles and, like liposomes, have great potential as drug-delivery systems. Our previous study revealed that polyethylene glycol (PEG) niosomes using different sorbitan ester (Span) surfactants (sorbitan monoester, Span 20, 40, 60, 80; sorbitan triester, Span 65) distributed within tumors similarly to PEG liposomes. The aim of this study was to encapsulate efficiently an anti-cancer drug, paclitaxel (PTX) into Span PEG niosomes, and evaluate PTX release profiles and anti-tumor efficacy of PTX-loaded Span PEG niosomes. Niosome sizes ranged between 100-150 nm, and the PTX encapsulation efficiency was more than 50%. All niosomes examined, in the presence of serum, yielded sustained PTX-release profiles. PTX release at 24 and 48 h from Span 80 PEG niosomes was significantly the highest among the other Span PEG niosomes examined. In C26 tumor-bearing mice, PTX-loaded Span 40 PEG niosomes (the lowest PTX release in vitro) suppressed tumor growth while PTX-loaded Span 80 PEG niosomes (the highest PTX release in vitro) did not. Thus, we succeeded in the control of PTX release from Span PEG niosomes by modifying the component of niosomes, and it influenced the effects of drugs loaded into niosomes. This demonstrates that the excellent NIS physicochemical properties of Spans make them an ideal candidate for anti-cancer drug-carrier niosomes.

The Synthesis, Characterization and Anti-Tumor Activity of a Cu-MOF Based on Flavone-6,2'-dicarboxylic Acid

A novel two-dimensional copper(II) framework (LDU-1), formulated as {[Cu₂(L)₂·2NMP}n (H₂L = flavone-6,2'-dicarboxylic acid, NMP = N-Methyl pyrrolidone), has been constructed under solvothermal conditions and characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), thermogravimetric analysis and powder X-ray diffraction (PXRD). In the crystal structure, the Cu(II) shows hex-coordinated with the classical Cu paddle-wheel coordination geometry, and the flavonoid ligand coordinates with the Cu(II) ion in a bidentate bridging mode. Of particular interest of LDU-1 is the presence of anti-tumor activity against three human cancer cell lines including lung adenocarcinoma(A549), Michigan cancer foundation-7 (MCF-7), erythroleukemia (K562) and murine melanoma B16F10, indicating synergistic enhancement effects between metal ions and organic linkers. A cell cycle assay indicates that LDU-1 induces cells to arrest at S phase obviously at a lower concentration.

Docetaxel-loaded redox-sensitive nanoparticles self-assembling from poly(caprolactone) conjugates with disulfide-linked poly(ethylene glycol)

In this study, novel redox-sensitive nanoparticles (NPs) were fabricated from the poly(caprolactone) conjugates with disulfide-linked poly(ethylene glycol) (DDMAT- mPEG-S-S-PCL, DPSP). The DPSP polymer was synthesized by ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. The obtaining of the DPSP polymer was confirmed by the ¹H nuclear magnetic resonance (¹H NMR) and Fourier transform infrared spectroscopy (FTIR) spectra. The DPSP NPs were fabricated with the solvent-evaporation method. Docetaxel (DTX) was employed as a model drug and encapsulated into the DPSP NPs. The in vitro anti-tumor activity of the DTX-loaded DPSP NPs and free DTX against the breast cancer cells (4T1) were evaluated by MTT assay. The cargo-free DPSP NPs were in circular shapes with an average diameter of 107.8 ± 0.4 nm. These NPs displayed redox-responsive behavior in the presence of glutathione. Animal experiments indicated that the DPSP NPs showed excellent blood compatibility and good bio-security. Cell tests suggested that the DPSP NPs could be taken in by 4T1 cells, smoothly, which improved the anti-tumor activity of free DTX.

Formulation of the novel structure curcumin derivative-loaded solid lipid nanoparticles: synthesis, optimization, characterization and anti-tumor activity screening in vitro

This study investigated the effect of structural modification of Curcumin (CU) combined with the solid lipid nanoparticles (SLN) drug delivery system on anti-tumor activity in vitro. A new structure of Curcumin derivative (CU1) was successfully synthesized by modifying the phenolic hydroxyl group of CU. CU1 was two times more stable than CU at 45 °C or constant light. The SLN containing CU1 (CU1-SLN) was prepared, and the particle size, polydispersity index, entrapment efficiency, drug loading, and zeta potential of CU1-SLN were (104.1 ± 2.43) nm, 0.22 ± 0.008, (95.1 ± 0.38) %, (4.28 ± 0.02) %, and (28.3 ± 1.60) mV, respectively. X-ray diffraction (XRD) and Differential scanning calorimetry (DSC) showed that CU1 is amorphous in SLN. CU1-SLN released the drug slowly for 48 h, while CU and CU1 were released rapidly within 8 h. In terms of cytotoxicity, CU1 exhibited a 1.5-fold higher inhibition than CU against A549 and SMMC-7721 cells, while CU1-SLN showed 2-fold higher inhibition than CU1. Both CU1 and CU1-SLN reduced the toxicity in normal hepatocytes compared with CU (2.6-fold and 12.9-fold, respectively). CU1-SLN showed a significant apoptotic effect (p < 0.05). In summary, CU1 retained the inhibitory effect of CU against tumor cells, while improving stability and safety. Additionally, CU1-SLN presents a promising strategy for the treatment of liver and lung cancer.

[Mechanism of Puerariae Lobatae Radix against lung cancer by inhibiting histone demethylase LSD1]

Histone lysine-specific demethylase 1(LSD1) has become a promising molecular target for lung cancer therapy. Upon the screening platform for LSD1 activity, some Chinese herbal extracts were screened for LSD1 activity inhibition, and the underlying mechanism was preliminarily investigated at both molecular and cellular levels. The results of LSD1 inhibition showed that Puerariae Lobatae Radix extract can effectively reduce LSD1 expression to elevate the expression of H3 K4 me2 and H3 K9 me2 substrates in H1975 and H1299 cells. Furthermore, Puerariae Lobatae Radix was evaluated for its anti-lung cancer activity. It had a potent inhibitory ability against the proliferation and colony formation of both H1975 and H1299 cells. Flow cytometry and DAPI staining assays indicated that Puerariae Lobatae Radix can induce the apoptosis of lung cancer cells. In addition, it can significantly suppress the migration and reverse the epithelial-mesenchymal transition(EMT) process of lung cancer cells by activating E-cadherin and suppressing the expression of N-cadherin, slug and vimentin. To sum up, Puerariae Lobatae Radix displayed a robust inhibitory activity against lung cancer, and the mechanism may be related to the down-regulation of LSD1 expression to induce the cell apoptosis and suppress the cell migration and EMT process. These findings will provide new insights into the action of Puerariae Lobatae Radix as an anti-lung cancer agent and offer new ideas for the study on the anti-cancer action of Chinese medicine based on the epigenetic modification.

[One new phenylethanoid glycoside from Forsythiae Fructus]

One new phenylethanoid glycoside was isolated from the ethyl acetate fraction of the 75% EtOH extract of Forsythiae Fructus by various column chromatographies(HP20, silica gel, ODS) and preparative HPLC.Its structure was identified as forsythiayanoside E(1) by physicochemical properties and extensive spectroscopic analysis(HR-ESI-MS, 1 D and 2 D NMR).Compound 1 was evaluated for cytotoxic activities by MTT assay and showed weak cytotoxic activity against MCF-7 and A-375 cell lines with inhibition rates of 39.85% and 43.38% at 40 μmol·L~(-1), and no cytotoxic activity against PC-3 and HepG2 cell lines at 100 μmol·L~(-1).

A Review on Acridines as Antiproliferative Agents

Acridine derivatives have been thoroughly investigated and discovered to have multitarget qualities, inhibiting topoisomerase enzymes that regulate topological changes in DNA and interfering with DNA's vital biological function. This article discusses current progress in the realm of novel 9-substituted acridine heterocyclic compounds, including the structure and structure-activity connection of the most promising molecules. The IC50 values of the new compounds against several human cancer cell lines will also be presented in the publication. The review also looks into the inhibition of topoisomerase by polycyclic aromatic compounds.

BACKGROUND

Acridine rings can be found in molecules used in many different areas, including industry and medicine. Nowadays, acridines with anti-bacterial activity are of research interest due to decreasing bacterial resistance. Some acridine derivatives showed antimalarial or antiviral activity. Acridine derivatives were also investigated for anti-tumor activity due to the interaction with topoisomerase II and DNA base pairs. Considering these possible uses of acridine derivatives, this work was made to overview of all significant structure performances for the specific action of these compounds.

OBJECTIVE

To review the activity of acridines as anti-proliferative agents.

DESIGN

This review is designed as acridines acting as topoisomerase I and II inhibitors/ poison, Acridines on the G-quadraplux interaction, Acridines with metal complexes, Acridines with quinacrine scaffold, Acridines with sulphur moiety.

CONCLUSION

Although introduced in the 19th century, acridine derivatives are still of scientific interest. In this review, acridine derivatives with various biological activities (antiparasitic, antiviral, anti-bacterial, and antiproliferative) and their structure-activity relationship analyses are presented. Although several mechanisms of their action are known, the only important are discussed here. It can be concluded that the dominant mechanisms are DNA intercalation and interaction with enzymes.

Thrombin-Activated Platelets Protect Vascular Endothelium against Tumor Cell Extravasation by Targeting Endothelial VCAM-1

When activated by thrombin, the platelets release their granular store of factors. These thrombin-activated platelets (TAPLT) have been shown to be capable of ameliorating pro-inflammatory processes. In this study, we tested if TAPLT could also protect the endothelium against tumor-related pro-inflammatory changes that promote angiogenesis and metastasis. Using endothelial cell (EC) models in vitro, we demonstrated that TAPLT protected EC against tumor conditioned medium (TCM)-induced increases of reactive oxygen species (ROS) production, EC permeability and angiogenesis, and inhibited transendothelial migration that was critical for cancer cell extravasation and metastasis. In vivo observations of TAPLT-mediated inhibition of angiogenesis and pulmonary colonization in a BALB/c nude mouse model were consistent with the in vitro findings. Neutralization of vascular cell adhesion molecule-1 (VCAM-1) binding significantly inhibited the ability of TAPLT to interact with EC and abrogated the TAPLT-mediated protection of EC against tumor angiogenesis and metastasis. Taken together, these findings suggest that VCAM-1-mediated linkage to EC is required for TAPLT to confer protection of EC against tumor-induced permeation and angiogenesis, thereby resisting tumor extravasation and metastasis.

Efficacy and Safety of Immune Checkpoint Inhibitor in Advanced Esophageal Squamous Cell Carcinoma: A Meta-Analysis

Background

The published evidence from several randomized controlled clinical trials of immunotherapy for advanced esophageal squamous cell carcinoma has shown promising results. This study aimed to investigate the efficacy and safety of immune checkpoint inhibitor treatment in esophageal squamous cell carcinoma.

Methods

PubMed, Web of Science, Cochrane Library, and Embase databases were searched for relevant articles published before December 30, 2020. The data for efficacy and safety of immune checkpoint inhibitor treatment were subjected to meta-analysis.

Results

Seven clinical trials comprising 1733 patients were included. The results showed that immune checkpoint inhibitor treatment as second- or later-line treatment was associated with an increased risk of the objective response rate (relative risk: 1.82, 95% confidence interval: 0.82–4.04; P=0.002) and median overall survival (hazard ratio: 0.75, 95% confidence interval: 0.67–0.85; P<0.001) compared with chemotherapy in locally advanced or metastatic esophageal squamous cell carcinoma. Moreover, immune checkpoint inhibitor treatment was associated with significant improvement in median overall survival (hazard ratio: 0.61, 95% confidence interval: 0.48–0.77, P<0.001) compared with chemotherapy in the programmed death-ligand 1 (PD-L1)-positive population. However, immune checkpoint inhibitor treatment was also effective in all patients independent of PD-L1 expression. The most common grade ≥3 treatment-related adverse events with immune checkpoint inhibitor therapy were anemia, asthenia, rash, fatigue, decreased appetite, diarrhea, pneumonia, decreased neutrophil count, and vomiting. Patients undergoing immune checkpoint inhibitor therapy was associated with a decreased risk of treatment-related adverse events (relative risk: 0.82, 95% confidence interval: 0.62–1.08; P<0.001) and grade ≥3 treatment-related adverse events (relative risk: 0.50, 95% confidence interval: 0.42–0.60; P<0.001) compared with those undergoing chemotherapy.

Conclusions

Immune checkpoint inhibitors as second- or later-line therapy may improve overall response rate and overall survival but not all oncological outcomes for patients with locally advanced or metastatic esophageal squamous cell carcinoma. Patients treated with immune checkpoint inhibitors might experience fewer treatment-related adverse events of any grade, but specifically grade ≥3, compared with those treated with chemotherapy.

Dual-Responsive Alginate Hydrogel Constructed by Sulfhdryl Dendrimer as an Intelligent System for Drug Delivery

Intelligent stimulus-triggered release and high drug-loading capacity are crucial requirements for drug delivery systems in cancer treatment. Based on the excessive intracellular GSH expression and pH conditions in tumor cells, a novel glutathione (GSH) and pH dual-responsive hydrogel was designed and synthesized by conjugates of glutamic acid-cysteine dendrimer with alginate (Glu-Cys-SA) through click reaction, and then cross-linked with polyethylene glycol (PEG) through hydrogen bonds to form a 3D-net structure. The hydrogel, self-assembled by the inner disulfide bonds of the dendrimer, is designed to respond to the GSH heterogeneity in tumors, with a remarkably high drug loading capacity. The Dox-loaded Glu-Cys-SA hydrogel showed controlled drug release behavior, significantly with a release rate of over 76% in response to GSH. The cytotoxicity investigation indicated that the prepared DOX-loaded hydrogel exhibited comparable anti-tumor activity against HepG-2 cells with positive control. These biocompatible hydrogels are expected to be well-designed GSH and pH dual-sensitive conjugates or polymers for efficient anticancer drug delivery.

One-Pot Synthesis of Phosphinylphosphonate Derivatives and Their Anti-Tumor Evaluations

This paper reports on the synthesis of new hydroxymethylene-(phosphinyl)phosphonates (HMPPs). A methodology has been developed to propose an optimized one-pot procedure without any intermediate purifications. Various aliphatic and (hetero)aromatic HMPPs were synthesized in good to excellent yields (53–98%) and the influence of electron withdrawing/donating group substitution on aromatic substrates was studied. In addition, the one-pot synthesis of HMPP was monitored by ³¹P NMR spectroscopy, allowing effective control of the end of the reaction and identification of all phosphorylated intermediate species, which enabled us to propose a reaction mechanism. Optimized experimental conditions were applied to the preparation of biological relevant aminoalkyl-HMPPs. A preliminary study of the complexation to hydroxyapatite (bone matrix) was carried out in order to verify its lower affinity towards bone compared to bisphosphonate molecules. Moreover, in vitro anti-tumor activity study revealed encouraging antiproliferative activities on three human cancer cell lines (breast, pancreas and lung).

Quinazoline Derivatives as Potential Therapeutic Agents in Urinary Bladder Cancer Therapy

Cancer diseases remain major health problems in the world despite significant developments in diagnostic methods and medications. Many of the conventional therapies, however, have limitations due to multidrug resistance or severe side effects. Bladder cancer is a complex disorder, and can be classified according to its diverse genetic backgrounds and clinical features. A very promising direction in bladder cancer treatment is targeted therapy directed at specific molecular pathways. Derivatives of quinazolines constitute a large group of chemicals with a wide range of biological properties, and many quinazoline derivatives are approved for antitumor clinical use, e.g.,: erlotinib, gefitinib, afatinib, lapatinib, and vandetanib. The character of these depends mostly on the properties of the substituents and their presence and position on one of the cyclic compounds. Today, new quinazoline-based compounds are being designed and synthesized as potential drugs of anticancer potency against bladder cancers.

Dihydroartemisinin: A Potential Drug for the Treatment of Malignancies and Inflammatory Diseases

Dihydroartemisinin (DHA) has been globally recognized for its efficacy and safety in the clinical treatment of malaria for decades. Recently, it has been found that DHA inhibits malignant tumor growth and regulates immune system function in addition to anti-malaria. In parasites and tumors, DHA causes severe oxidative stress by inducing excessive reactive oxygen species production. DHA also kills tumor cells by inducing programmed cell death, blocking cell cycle and enhancing anti-tumor immunity. In addition, DHA inhibits inflammation by reducing the inflammatory cells infiltration and suppressing the production of pro-inflammatory cytokines. Further, genomics, proteomics, metabolomics and network pharmacology of DHA therapy provide the basis for elucidating the pharmacological effects of DHA. This review provides a summary of the recent research progress of DHA in anti-tumor, inhibition of inflammatory diseases and the relevant pharmacological mechanisms. With further research of DHA, it is likely that DHA will become an alternative therapy in the clinical treatment of malignant tumors and inflammatory diseases.

Synthesis and Anti-cancer Activity of Paclitaxel-Coumarin Conjugate

BACKGROUND

Paclitaxel, a natural diterpenoid compound, has anti-tumor effect by acting on tubulin, whereas coumarin, another kind of natural product, has anti-tumor effect, along with some other effects, such as anti-bacterial-., Moreover, it also possesses fluorescence.

OBJECTIVE

Multi targeting is an effective strategy in drug design to combat tumor. Therefore, a combination of paclitaxel with other active molecular drugs for exploring the novel lead with multi-functions is in demand.

MATERIALS AND METHODS

To synthsize paclitaxel-coumarin conjugate via click chemistry and to investigate anticancer activity by MTT assay and the scratch test.

RESULTS AND DISCUSSION

The results of MTT assay showed that compared tothe paclitaxel, the anti-tumor activity of the conjugate was significantly improved. The results of flow cytometry showed that the conjugate had a stronger ability to induce apoptosis. The scratch test results showed that the conjugate had better anti- metastasis ability than paclitaxel.

CONCLUSION

These findings indicated that paclitaxel and coumarin had a synergistic effect, which paved the way for the development of paclitaxel through fluorescence.

Preparation, characterization, and anti-colon cancer activity of oridonin-loaded long-circulating liposomes

In this study, oridonin-loaded long-circulating liposomes (LC-lipo@ORI) were prepared with the ethanol injection method. Its physicochemical properties and the morphology were characterized, and its stability and release profiles were evaluated. Furthermore, its antitumor effects were studied using two in vitro cell models of colon cancer and two tumor-bearing models in nude mice. The prepared LC-lipo@ORI was quasi-spherical, with a mean particle size of 109.55 ± 2.30 nm. The zeta potential was -1.38 ± 0.21 mV, the encapsulation efficiency was 85.79%±3.25%, and the drug loading was 5.87%±0.21%. In vitro release results showed that the cumulative release rate of LC-lipo@ORI at 12 h was 63.83%. However, ORI dispersion was almost completely released after 12 h. In vitro cytotoxicity results showed that, the inhibiting effects of LC-lipo@ORI on the proliferation of two types of colon cancer cells were apparently higher than those of ORI dispersion, whereas those of the blank carrier were not noticeable. In vivo studies confirmed that, the encapsulation of LC-lipo enhanced the inhibitory effects of ORI on tumor growth. These results indicated that LC-lipo@ORI a promising formulations for colon cancer treatment.

[Research on anti-tumor natural product diosgenin]

Diosgenin is widely distributed in many plants, such as Polygonatum sibiricum, Paris polyphylla, Dioscorea oppositifolia, Trigonella foenum-graecum, Costus speciosus, Tacca chantrieri, which has good anti-tumor activity and preferable effects on preventing atherosclerosis, protecting the heart, treating diabetes, etc. This review combed through the anti-tumor mechanisms of diosgenin encompassing lung, breast, gallbladder, liver, oral cavity, stomach, bladder, bone marrow, etc. Besides, it was discovered that diosgenin mainly exerts its effect by inhibiting tumor cell migration, suppressing tumor cell proliferation and growth, and inducing cell apoptosis. However, problems like low yield and bioavailability frequently exist in natural diosgenin. This review introduced methods such as structural modification, dosage form optimization and combination medication to improve the yield and anti-tumor activity of diosgenin. Via the summary of this paper, it is expected to provide theoretical basis for the rational exploitation and utilization of diosgenin.

[Anti-tumor activity of tigecycline: a review]

Tigecycline is a novel glycylcycline antibacterial drug, which shows both antibiotic function and anti-tumor activity. This review summarizes the single and combined use of tigecycline for tumor treatment and the underpinning mechanisms. As an inhibitor for mitochondrial DNA translation, tigecycline affects the proliferation, migration, and invasion of tumor cells mainly through inhibiting mitochondrial protein synthesis and inducing mitochondrial dysfunction. Although the effect of tigecycline monotherapy is controversial, the efficacy of combined use of tigecycline is satisfactory. Therefore, it is important to explore the molecular mechanisms underpinning the anti-tumor activity of tigecycline, with the aim to use it as a cheap and effective new anti-tumor drug.

Synthesis of Murrayaquinone-A Derivatives and Investigation of Potential Anticancer Properties

A series of novel murrayaquinone a derivatives were synthesized and their anti-cancer activity were evaluated on healthy colon cell lines (CCD-18Co), primary (Caco-2) and metastatic (DLD-1) colon cancer cell lines. The results showed that the cytotoxicity of murrayaquinone molecules is significantly high even in micromolar levels. The DNA binding, cell cycle arrest and metabolic activity studies of these molecules were also carried out and the results showed that these molecules induce apoptosis. In conclusion, the data support further studies on murrayaquinone derivatives toward selection of a candidate for cancer treatment.

MitoTracker Deep Red (MTDR) Is a Metabolic Inhibitor for Targeting Mitochondria and Eradicating Cancer Stem Cells (CSCs), With Anti-Tumor and Anti-Metastatic Activity In Vivo

MitoTracker Deep Red (MTDR) is a relatively non-toxic, carbocyanine-based, far-red, fluorescent probe that is routinely used to chemically mark and visualize mitochondria in living cells. Previously, we used MTDR at low nano-molar concentrations to stain and metabolically fractionate breast cancer cells into Mito-high and Mito-low cell sub-populations, by flow-cytometry. Functionally, the Mito-high cell population was specifically enriched in cancer stem cell (CSC) activity, i) showing increased levels of ESA cell surface expression and ALDH activity, ii) elevated 3D anchorage-independent growth, iii) larger overall cell size (>12-μm) and iv) Paclitaxel-resistance. The Mito-high cell population also showed enhanced tumor-initiating activity, in an in vivo preclinical animal model. Here, we explored the hypothesis that higher nano-molar concentrations of MTDR could also be used to therapeutically target and eradicate CSCs. For this purpose, we employed an ER(+) cell line (MCF7) and two triple negative cell lines (MDA-MB-231 and MDA-MB-468), as model systems. Remarkably, MTDR inhibited 3D mammosphere formation in MCF7 and MDA-MB-468 cells, with an IC-50 between 50 to 100 nM; similar results were obtained in MDA-MB-231 cells. In addition, we now show that MTDR exhibited near complete inhibition of mitochondrial oxygen consumption rates (OCR) and ATP production, in all three breast cancer cell lines tested, at a level of 500 nM. However, basal glycolytic rates in MCF7 and MDA-MB-468 cells remained unaffected at levels of MTDR of up to 1 μM. We conclude that MTDR can be used to specifically target and eradicate CSCs, by selectively interfering with mitochondrial metabolism, by employing nano-molar concentrations of this chemical entity. In further support of this notion, MTDR significantly inhibited tumor growth and prevented metastasis in vivo, in a xenograft model employing MDA-MB-231 cells, with little or no toxicity observed. In contrast, Abemaciclib, an FDA-approved CDK4/6 inhibitor, failed to inhibit metastasis. Therefore, in the future, MTDR could be modified and optimized via medicinal chemistry, to further increase its potency and efficacy, for its ultimate clinical use in the metabolic targeting of CSCs for their eradication.

5,6-Epoxycholesterol Isomers Induce Oxiapoptophagy in Myeloma Cells

Simple Summary

As the second most frequent hematological malignancy, multiple myeloma remains incurable with recurrent patient relapse due to drug resistance. Therefore, the development of novel and potent therapies is urgently required. Herein, we demonstrated the anti-tumor activity of 5,6 α- and 5,6 β-epoxycholesterol isomers against human myeloma cells. Our results highlighted a striking anti-myeloma efficiency of these bioactive molecules and their added value in future potential treatments including combination therapy of multiple myeloma.

Abstract

Multiple myeloma (MM) is an incurable plasma cell malignancy with frequent patient relapse due to innate or acquired drug resistance. Cholesterol metabolism is reported to be altered in MM; therefore, we investigated the potential anti-myeloma activity of two cholesterol derivatives: the 5,6 α- and 5,6 β-epoxycholesterol (EC) isomers. To this end, viability assays were used, and isomers were shown to exhibit important anti-tumor activity in vitro in JJN3 and U266 human myeloma cell lines (HMCLs) and ex vivo in myeloma patients’ sorted CD138+ malignant cells. Moreover, we confirmed that 5,6 α-EC and 5,6 β-EC induced oxiapoptophagy through concomitant oxidative stress and caspase-3-mediated apoptosis and autophagy. Interestingly, in combination treatment a synergistic interaction was observed between 5,6 α-EC and 5,6 β-EC on myeloma cells. These data highlight a striking anti-tumor activity of 5,6 α-EC and 5,6 β-EC bioactive molecules against human myeloma cells, paving the way for their potential role in future therapeutic strategies in MM.

The Highly Regioselective Synthesis of Novel Imidazolidin-2-Ones via the Intramolecular Cyclization/Electrophilic Substitution of Urea Derivatives and the Evaluation of Their Anticancer Activity

A series of novel 4-(het)arylimidazoldin-2-ones were obtained by the acid-catalyzed reaction of (2,2-diethoxyethyl)ureas with aromatic and heterocyclic C-nucleophiles. The proposed approach to substituted imidazolidinones benefits from excellent regioselectivity, readily available starting materials and a simple procedure. The regioselectivity of the reaction was rationalized by quantum chemistry calculations and control experiments. The anti-cancer activity of the obtained compounds was tested in vitro.

The Application of Peptides in Glioma: a Novel Tool for Therapy

BACKGROUND

Glioma is the most aggressive and lethal tumor of the central nervous system. Owing to the cellular heterogeneity, the invasiveness, and blood-brain barrier (BBB), current therapeutic approaches, such as chemotherapy and radiotherapy, are poorly to obtain great anti-tumor efficacy. However, peptides, a novel type of therapeutic agent, displayed excellent ability in the tumor, which becomes a new molecule for glioma treatment.

METHOD

We review the current knowledge on peptides for the treatment of glioma through a PubMed-based literature search.

RESULTS

In the treatment of glioma, peptides can be used as (i) decoration on the surface of the delivery system, facilitating the distribution and accumulation of the anti-tumor drug in the target site;(ii) anti-tumor active molecules, inhibiting the growth of glioma and reducing solid tumor volume; (iii) immune-stimulating factor, and activating immune cells in the tumor microenvironment or recruiting immune cells to the tumor for breaking out the immunosuppression by glioma cells.

CONCLUSION

The application of peptides has revolutionized the treatment of glioma, which is based on targeting, penetrating, anti-tumor activities, and immunostimulatory. Moreover, better outcomes have been discovered in combining different kinds of peptides rather than a single one. Until now, more and more preclinical studies have been developed with multifarious peptides, which show promising results in vitro or vivo with the model of glioma.

Anti-tumor Activity of Propofol: A Focus on MicroRNAs

BACKGROUND

MicroRNAs are endogenous, short, non-coding RNAs with the length as low as 20 to 25 nucleotides. These RNAs are able to negatively affect the gene expression at the post-transcriptional level. It has been demonstrated that microRNAs play a significant role in cell proliferation, cell migration, cell death, cell differentiation, infection, immune response, and metabolism. Besides, the dysfunction of microRNAs has been observed in a variety of cancers. So, modulation of microRNAs is of interest in the treatment of disorders.

OBJECTIVE

The aim of the current review is to investigate the modulatory effect of propofol on microRNAs in cancer therapy.

METHODS

This review was performed at PubMed, SCOPUS and Web of Science data-bases using keywords "propofol', "microRNA", "cancer therapy", "propofol + microRNA" and "propofol + miR".

RESULTS

It was found that propofol dually down-regulates/upregulates microRNAs to exert its antitumor activity. In terms of oncogenesis microRNAs, propofol exert an inhibitory effect, while propofol significantly enhances the expression of oncosuppressor microRNAs.

CONCLUSION

It seems that propofol is a potential modulator of microRNAs and this capability can be used in the treatment of various cancers.

Discovery of a Highly Potent and Novel Gambogic Acid Derivative as an Anticancer Drug Candidate

BACKGROUND AND PURPOSE

Gambogic Acid (GA), a promising anti-cancer agent isolated from the resin of Garcinia species in Southeast Asia, exhibits high potency in inhibiting a wide variety of cancer cells' growth. Moreover, the fact that it is amenable to chemical modification makes GA an attractive molecule for the development of anti-cancer agents.

METHODS

Gambogic acid-3-(4-pyrimidinyloxy) propyl ester (compound 4) was derived from the reaction between 4-hydroxypropoxy pyrimidine and GA. Its structure was elucidated by comprehensive analysis of ESIMS, HRESIMS, 1 D NMR data. Anti-tumor activities of compound 4 and GA in vitro against HepG-2, A549 and MCF-7 cells were investigated by MTT assay. FITC/PI dye was used to test apoptosis. The binding affinity difference of compound 4 and GA binding to IKKβ was studied by using Discovery Studio 2016.

RESULTS

Compound 4 was successfully synthesized and showed strong inhibitory effects on HepG-2, A549 and MCF-7 cells lines with an IC₅₀ value of 1.49±0.11, 1.37±0.06 and 0.64±0.16μM, respectively. Molecular docking study demonstrated that four more hydrogen bonds were established between IKKβ and compound 4, compared with GA.

CONCLUSION

Our results suggested that compound 4 showed significant effects in inducing apoptosis. Further molecular docking study indicated that the introduction of pyrimidine could improve GA's binding affinity to IKKβ. Compound 4 may serve as a potential lead compound for the development of new anti-cancer drugs.

Synergistic Combination of Bioactive Hydroxyapatite Nanoparticles and the Chemotherapeutic Doxorubicin to Overcome Tumor Multidrug Resistance

Multidrug resistance (MDR) is one of the biggest obstacles in cancer chemotherapy. Here, a remarkable reversal of MDR in breast cancer through the synergistic effects of bioactive hydroxyapatite nanoparticles (HAPNs) and doxorubicin (DOX) is shown. DOX loaded HAPNs (DHAPNs) exhibit a 150-fold reduction in IC₅₀ compared with free DOX for human MDR breast cancer MCF-7/ADR cells, and lead to almost complete inhibition of tumor growth in vivo without obvious side effects of free DOX. This high efficacy and specificity could be attributed to multiple action mechanisms of HAPNs. In addition to acting as the conventional nanocarriers to facilitate the cellular uptake and retention of DOX in MCF-7/ADR cells, more importantly, drug-free HAPNs themselves are able to prevent drug being pumped out of MDR cells through targeting mitochondria to induce mitochondrial damage and inhibit ATP production and to trigger sustained mitochondrial calcium overload and apoptosis in MDR cancer cells while not affecting normal cells. The results demonstrate that this simple but versatile bioactive nanoparticle provides a practical approach to effectively overcome MDR.

Vaccaria segetalis: A Review of Ethnomedicinal, Phytochemical, Pharmacological, and Toxicological Findings

Vaccaria segetalis is a dry mature seed of Vaccaria hispanica (Mill.) Rauschert, which belongs to the genus V. segetalis (Neck.) Garcke. There are multiple medicinal parts of V. segetalis, according to the records, including roots, stems, leaves, flowers, and seeds, which should be used together. Currently, V. segetalis is most frequently used in the treatment of menstruation, dysmenorrhea, breast milk stoppages, and chylorrhea. Numerous studies present historical evidence of the use of V. segetalis to treat several diseases and describe its beneficial effects including prolactin- (PRL-) like, estrogen-like, antitumor, antiangiogenesis, and antioxidant activity. We summarized the period from January 1980 to December 2019 regarding V. segetalis. This review paper indicates that V. segetalis has promising clinical applications. The main active ingredients of the plant have been elucidated in recent years. We summarized the previously and newly discovered pharmacological effects of V. segetalis in addition to its active ingredients, ethnopharmacological uses, and toxicological properties, and provided a focus for future research.

[Construction of an adriamycin-glycyrrhizin molecular complex and assessment of its antitumor activity]

OBJECTIVE

To prepare an adriamycin-glycyrrhizin molecular complex (ADR-GL complex) using glycyrrhizin (GL, a component in traditional Chinese drug) as the carrier and assess the solubility and anti-tumor activity of the complex.

OBJECTIVE

Dried solid products of ADR-GL complex with different molar ratios of ADR and GL (2∶1, 1∶1, and 1∶2) were prepared by rotary steaming and characterized using FT-IR and DSC. The products were dissolved in pH7.4 phosphate buffer, sonicated overnight, and centrifuged to obtain saturated ADR-GL complex solution, and ADR solubility was determined using high-performance liquid chromatography (HPLC). The cytotoxicity of ADR and ADR-GL complex was evaluated in HepG2 cells by assessing the cell viability using MTT assay. Breast cancer MDA-MB-231 cells were treated with ADR-GL complex and the proportion of CD44+ cells in the total cells was measured by flow cytometry to evaluate the anti- tumor activity of the complex.

OBJECTIVE

FT-IR spectrum of solid ADR-GL complex did not show the absorption peak of adriamycin at 1525 cm-1, and an intense absorption peak of ADR-GL occurred at 86 ℃ in DSC, indicating that ADR molecules were encapsulated by GL, the giving rise to the new form of ADR-GL molecular complex. The solubility of ADR in pH7.4 phosphate buffer in the control group was 0.844±0.011 mmol/L, significantly different from that in ADR-GL complex group (P < 0.05). The ADR-GL complex with an ADR to GL ratio of 1∶2 showed the highest ADR solubility (5.562±0.049 mmol/L), which was 6.3 times that of the control sample. The ADR-GL complex and ADR showed similar inhibitory effects on HepG2 cells and the negative stemness population of MDA-MB-231 stem cells.

OBJECTIVE

The ADR-GL complex does not reduce the antitumor activity of ADR and may serve potentially as a safe and novel drug delivery system.