Rhein potentiates doxorubicin in treating triple negative breast cancer by inhibiting cancer-associated fibroblasts.

Cancer-associated fibroblasts (CAFs), one of the most abundant stromal cells in the tumor microenvironment, mediate desmoplastic responses. CAFs are major drivers for the failure of triple-negative breast cancer (TNBC) chemotherapy. It is well-documented that many traditional Chinese medicines (TCMs) exhibit potent anti-fibrotic effects based on their capacity to suppress the production of ECM proteins. Therefore, the combination of TCMs exhausting CAFs with chemotherapy is a potential regimen for treating TNBC. Here, TGF-ß was used to induce the transformation of NIH/3T3 cells into CAFs for screening TCMs to inhibit tumor fibrosis. After screening 11 candidate TCMs for inhibiting CAFs using the TMS method, rhein (Rhe) was found to strongly inhibit the proliferation of CAFs. Therefore, Rhe was chosen as a representative TCM to inhibit CAFs in TNBC. A 4T1Fluc/CAFs tumor sphere resembling the TME in vivo was constructed to explore the feasibility of inhibiting CAFs to sensitize DOX in treating TNBC. It was found that CAFs apparently hindered the penetration of DOX into 4T1Fluc/CAFs tumor spheres and decreased the the sensitivity of 4T1Fluc cells to DOX, while Rhe significantly restored the sensitivity of 4T1Fluc cells to DOX by inhibiting the proliferation of CAFs. Consistent with in vitro results, Rhe reversed the abnormal activation of CAFs and diminished the accumulation of collagen in 4T1Fluc mouse xenograft models. This removal of stromal barrier facilitated the antitumor efficacy of DOX. Altogether, this study demonstrated for the first time that Rhe could inhibit tumor tissue fibrosis and synergize DOX to treat TNBC.

Sanhuang Xiexin Decoction Ameliorates TNBC By Modulating JAK2-STAT3 and Lipid Metabolism.

OBJECTIVE: To investigate the therapeutic effect of Sanhuang Xiexin Decoction (SXD) on triple-negative breast cancer (TNBC) in mice and its underlying mechanism. METHODS: The high-performance liquid chromatography (HPLC) was used to quantitate and qualify SXD. A total of 15 female BALB/c mice were inoculated subcutaneously on the right hypogastrium with 3×105 of 4T1-Luc cells to establish TNBC mouse model. All mice were divided randomly into 3 groups, including phosphate buffered solution (PBS), SXD and doxorubicin (DOX) groups (positive drug). Additionally, tumor growth, pathological changes, serum lipid profiles, expression of Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway and its key targets including inflammatory factors, cell cycle and epithelial-mesenchymal transition (EMT) markers were investigated. Besides, the biosafety of SXD was also evaluated in mice. RESULTS: Rhein, coptisine, berberine hydrochloride and baicalin were all found in SXD, and the concentrations of these 4 components were 0.57, 2.61, 2.93, and 46.04 mg/g, respectively. The mouse experiment showed that SXD could notably suppress the development of tumors and reduce the density of tumor cells (P<0.01). The serum lipid analysis and Oil-Red-O staining both showed the differences, SXD group exhibited higher serum adiponectin and HDL-C levels with lower TC and LDL-C levels compared to the PBS and DOX groups (P<0.05 or P<0.01), respectively. SXD also decreased the levels of phospho-JAK2 (p-JAK2), phospho-STAT3 (p-STAT3) expressions and its downstream factors, including mostly inflammatory cytokine, EMT markers, S phase of tumor cells and vascular endothelial growth factor (VEGF) expression (P<0.05 or P<0.01), respectively. The biosafety assessment of SXD revealed low levels of toxicity in mice. CONCLUSION: SXD could inhibit TNBC by suppressing JAK2-STAT3 phosphorylation which may be associated with modulation of lipid metabolism.

Integrated animal experiments and network pharmacology for investigating therapeutic effect of celastrol-loaded liposomes on NAFLD.

BACKGROUND: The prevalence of Non-alcoholic Fatty Liver Disease (NAFLD) is closely related to the increase of the incidence rate of obesity. AIMS: To find out the targets of celastrol on NAFLD with the treatment of celastrol-loaded liposomes (Cel-Lips). METHODS: Gene Expression Omnibus (GEO) data were used to compare the expression of differential genes in NAFLD patients with normal individuals. Celastrol was loaded into liposomes to improve its solubility, as well as, achieving a passive targeting effect on the liver to improve the availability, which also could delay the release rate of celastrol to prolong the action time and thus reduce the frequency of administration. Due to rarely reported molecular mechanisms of celastrol, with the help of network pharmacological analysis, the targets of celastrol acting on NAFLD were predictively analyzed. RESULTS: An association between NAFLD and lipid metabolism was detected in GEO data. Cel-Lips significantly alleviated NAFLD in vivo. Through network pharmacology, it was found that most of the action pathways of celastrol were related to lipid metabolism. CONCLUSION: Celastrol has the potential to treat NAFLD, and its possible targets have been identified through network pharmacological screening, which provides a certain basis for the follow-up researches.

Relaxin-encapsulated polymeric metformin nanoparticles remodel tumor immune microenvironment by reducing CAFs for efficient triple-negative breast cancer immunotherapy.

Cancer-associated fibroblasts (CAFs) are one of the most abundant stromal cells in the tumor microenvironment which mediate desmoplastic response and are the primary driver for an immunosuppressive microenvironment, leading to the failure of triple-negative breast cancer (TNBC) immunotherapy. Therefore, depleting CAFs may enhance the effect of immunotherapy (such as PD-L1 antibody). Relaxin (RLN) has been demonstrated to significantly improve transforming growth factor-ß (TGF-ß) induced CAFs activation and tumor immunosuppressive microenvironment. However, the short half-life and systemic vasodilation of RLN limit its in vivo efficacy. Here, plasmid encoding relaxin (pRLN) to locally express RLN was delivered with a new positively charged polymer named polymeric metformin (PolyMet), which could increase gene transfer efficiency significantly and have low toxicity that have been certified by our lab before. In order to improve the stability of pRLN in vivo, this complex was further formed lipid poly-γ-glutamic acid (PGA)/PolyMet-pRLN nanoparticle (LPPR). The particle size of LPPR was 205.5 ± 2.9 nm, and the zeta potential was +55.4 ± 1.6 mV. LPPR displayed excellent tumor penetrating efficacy and weaken proliferation of CAFs in 4T1luc/CAFs tumor spheres in vitro. In vivo, it could reverse aberrantly activated CAFs by decreasing the expression of profibrogenic cytokine and remove the physical barrier to reshape the tumor stromal microenvironment, which enabled a 2.2-fold increase in cytotoxic T cell infiltration within the tumor and a decrease in immunosuppressive cells infiltration. Thus, LPPR was observed retarded tumor growth by itself in the 4T1 tumor bearing-mouse, and the reshaped immune microenvironment further led to facilitate antitumor effect when it combined with PD-L1 antibody (aPD-L1). Altogether, this study presented a novel therapeutic approach against tumor stroma using LPPR to achieve a combination regimen with immune checkpoint blockade therapy against the desmoplastic TNBC model.

Screening Multidrug Resistance Reversal Agents in Traditional Chinese Medicines by Efflux Kinetics of D-Luciferin in MCF-7/DOXFluc Cells.

In this study, we established a simple and rapid in vitro method for screening multidrug resistance (MDR) reversal agents in traditional Chinese medicines (TCMs), which could better correspond to the MDR reversing effect in vivo. Here, D-luciferin, a substrate for the enzyme firefly luciferase and also a substrate for ATP-binding cassette transporters (ABC transporters), was used as the probe to detect its efflux kinetics caused by ABC transporters. First, we established a stable doxorubicin (DOX)-resistant cell line (MCF-7/DOXFluc) that overexpressed luciferase. Then, some kinds of TCMs were chosen for the MDR reversal agents to measure its effect on inhibiting the D-luciferin outflow from MCF-7/DOXFluc, and the ideal reversal agent with the least D-luciferin efflux from MCF-7/DOXFluc was selected to further investigate its effect combined with DOX on MCF-7/DOXFluc tumor-bearing mice. The results indicated that quercetin (Qu) could remarkably increase the retention of D-luciferin in MCF-7/DOXFluc in vitro and in vivo. Also, the combination of Qu and DOX could exceedingly inhibit the tumor growth, which proved the feasibility of this in vitro screening method. The study proposed a feasible method for mass screening of MDR agents from TCMs in vitro.

Preparation and Quality Evaluation of Honokiol Nanoparticles Using a New Polysaccharide Polymer as its Carrier.

OBJECTIVE: To improve the solubility of Honokiol (HNK), Honokiol nanoparticles (HNK-NPs) were prepared using a new biodegradable polysaccharide polymer as its carrier. METHODS: HNK-NPs were prepared by hydrophilic polymer coagulation method, and the processing parameters were optimized according to average particle size and PDI by a single factor experiment. The morphology of the optimized nanoparticles was investigated by TEM, and the in vitro release was carried out to evaluate the optimized HNK-NPs. RESULTS: The encapsulation efficiency and drug loading of the HNK-NPs were 77.75 ± 2.63% and 13.46 ± 0.39%, respectively. The obtained nanoparticles of HNK-NPs were spherical-like under the electron microscope with a mean particle size of 198.50 ± 0.01 nm and a Zeta potential of -52.60 ± 1.00 mV. The in vitro release results showed that the cumulative release rates of nanoparticles were 48.28 ± 9.80% and 81.12 ± 4.35% within 2 h and 8 h, respectively, showing a stable release behavior. The average particle size and PDI of HNK-NPs solution prepared by the hydrophilic polymer condensation method had no obvious change at 72h. CONCLUSION: HNK-NPs were successfully prepared by the phase separation method. This new polysaccharide polymer should be an ideal carrier to help improve the solubility of HNK.

Pharmacokinetics of ginkgolide B-lyophilized nanoparticles after intravenous injection in rats using liquid chromatography-tandem mass spectrometry.

RATIONALE: Ginkgolide B (GB) performs diverse pharmacological activities but has poor water solubility. The currently available GB injections have a short half-life and are lethal when injected rapidly. We prepared GB-lyophilized nanoparticles (GB-NPs) using a new nonsurfactant polysaccharide polymer, ZY-010, as its carrier to regulate the release of GB in vivo. Here, the pharmacokinetics (PK) of GB-NPs after intravenous injection in rats was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS: The samples were separated on an Agilent Eclipse XDB-C 18 column (2.1 × 50 mm, 1.85 µm) maintained at 30°C. The MS/MS transitions of GB and glibenclamide as the internal standard (IS) were set at m/z 423.1 → 367.1 and m/z 492.1 → 367.0, respectively. The standard curve of GB content was constructed, and the specificity, sensitivity, precision, and extraction recovery of LC-MS/MS analysis were assessed. The main PK parameters were analyzed using DAS (Drug And Statistics for Windows) software, version 2.0. RESULTS: The retention time of GB and IS at elution was 2.77 and 4.75 min, respectively. An excellent linear response across the concentration range of 0.001-100 µg/ml was achieved (r = 0.9997). The relative standard deviation value of precision was less than 10%. The total extraction recovery was above 80.76 ± 2.08%. The main PK parameters for the GB-NPs were as follows: t1/2 = 69.32 h, AUC(0 → ∞) = 188 312.97 ± 143 312.41 µg/L h, CL = 0.03 ± 0.02 L/h/kg, and V = 0.09 ± 0.05 L/kg. The t1/2 of the GB-NPs was significantly longer than that of GB solution, and AUC(0 → ∞) of GB-NPs was about 1.4 times that of GB solution. The PK data demonstrated that the blood concentration of GB in rats conformed to a three-compartment model in both GB solution and GB-NPs. CONCLUSION: A rapid and accurate LC-MS/MS method was established for the determination of GB-NPs in rats. GB-NPs exhibited a sustained-release behavior in vivo compared with GB solution.

Reversing multi-drug resistance by polymeric metformin to enhance antitumor efficacy of chemotherapy.

Multi-drug resistance (MDR) in breast cancer poses a great threat to chemotherapy. The expression and function of the ATP binding cassette (ABC) transporter are the major cause of MDR. Herein, a linear polyethylene glycol (PEI) conjugated with dicyandiamide, which called polymeric metformin (PolyMet), was successfully synthesized as a simple and biocompatible polymer of metformin. PolyMet showed the potential to reverse MDR by inhibiting the efflux of the substrate of ATP-binding cassette (ABC) transporter from DOX resistant MCF-7 cells (MCF-7/DOX). To test its MDR reversing effect, PolyMet was combined with DOX to treat mice carrying MCF-7/DOX xenografts. In order to decrease the toxicities of DOX and delivery PolyMet and DOX to tumor at the same time, PolyMet was complexed with poly-γ-glutamic acid-doxorubicin (PGA-DOX) electrostatically at the optimal ratio of 2:3, which were further coated with lipid membrane to form lipid/PolyMet-(PGA-DOX) nanoparticles (LPPD). The particle size of LPPD was 165.8 nm, and the zeta potential was +36.5 mV. LPPD exhibited favorable cytotoxicity and cellular uptake in MCF-7/DOX. Meanwhile, the bioluminescence imaging and immunohistochemical analysis indicated that LPPD effectively conquered DOX-associated MDR by blocking ABC transporters (ABCB1 and ABCC1) via PolyMet. Remarkably, LPPD significantly inhibited the tumor growth and lowered the systemic toxicity in a murine MCF-7/DOX tumor model. This is the first time to reveal that PolyMet can enhance the anti-tumor efficacy of DOX by dampening ABC transporters and activating the AMPK/mTOR pathway, which is a promising strategy for drug-resistant breast cancer therapy.

Baicalein modulates the radiosensitivity of cervical cancer cells in vitro via miR-183 and the JAK2/STAT3 signaling pathway.

BACKGROUND: Increasing radiosensitivity of cancer cells can enhance the efficacy of cervical cancer treatment. OBJECTIVES: This study evaluated the potential roles and mechanism of baicalein in regulating the radiosensitivity of cervical cancer cells in vitro. MATERIAL AND METHODS: Real-time quantitative polymerase chain reaction (RT-qPCR) was used to assess miR-183 expression in End1/E6E7 cells, Hela cells and Hela cells irradiated with X-ray (0 Gy, 1 Gy, 3 Gy, 5 Gy, and 10 Gy). Cell Counting Kit-8 (CCK-8) method measured cell viability of Hela cells after miR-183 regulation, baicalein or RO8191 treatment. Apoptosis rates were detected using flow cytometry. Thereafter, expression of Bcl-2, Bax and caspase-3 RNA was also detected through RT-qPCR. Protein concentrations of E-cadherin, N-cadherin, Vimentin in epithelial-mesenchymal transition (EMT), phospho-JAK2/STAT3, and total Janus kinase 2/signal transducer and activator of transcription 3 STAT3 (JAK2/STAT3) were examined using enzyme-linked immunosorbent assay (ELISA) methods. RO8191, a JAK2/STAT3 activator, was used to activate the JAK2/STAT3 signaling pathway. RESULTS: The miR-183 expression was significantly lower in Hela cells compared to End1/E6E7 cells. Following upregulation of miR-183 in Hela cells, cell viability was inhibited while apoptosis was promoted. Moreover, EMT was inhibited after miR-183 over-expression. X-ray treatment markedly reduced the cell survival rate and increased miR-183 RNA expression. Baicalein treatment severely reduced the cell viability of 10-Gy X-ray-irradiated Hela cells, partially reversing the effect of miR-183, and also increased apoptosis and prevented EMT in irradiated cells. Y1007/8 in JAK2 and tyrosine (Tyr) residue 705 of STAT3 were phosphorylated, resulting in high expression of JAK2/STAT3, which was decreased by irradiation and baicalein treatment. RO8191 activated JAK2/STAT3 signaling, promoted cell viability and EMT, and inhibited cell apoptosis, while baicalein partly reversed the functions of RO8191. CONCLUSIONS: Baicalein inhibited cell viability and EMT, and induced cell apoptosis of Hela cells, through upregulating miR-183 via inactivation of the JAK2/STAT3 signaling pathway.

Regression models for near-infrared measurement of subcutaneous adipose tissue thickness.

Obesity is often associated with the risks of diabetes and cardiovascular disease, and there is a need to measure subcutaneous adipose tissue (SAT) thickness for acquiring the distribution of body fat. The present study aimed to develop and evaluate different model-based methods for SAT thickness measurement using an SATmeter developed in our laboratory. Near-infrared signals backscattered from the body surfaces from 40 subjects at 20 body sites each were recorded. Linear regression (LR) and support vector regression (SVR) models were established to predict SAT thickness on different body sites. The measurement accuracy was evaluated by ultrasound, and compared with results from a mechanical skinfold caliper (MSC) and a body composition balance monitor (BCBM). The results showed that both LR- and SVR-based measurement produced better accuracy than MSC and BCBM. It was also concluded that by using regression models specifically designed for certain parts of human body, higher measurement accuracy could be achieved than using a general model for the whole body. Our results demonstrated that the SATmeter is a feasible method, which can be applied at home and in the community due to its portability and convenience.

The radiation-sensitizing effect of flavopiridol in the esophageal cancer cell line Eca109.

Flavopiridol is a cyclin-dependent kinase inhibitor. It has shown an antitumor effect against several cancers. In the present study, the radiation-sensitizing effect of flavopiridol was investigated in an esophageal squamous carcinoma cell line, Eca109. The growth inhibitory rate of Eca109 with flavopiridol was determined using the MTT and the radio-sensitizing rate using clonogenic survival assays. The cell cycle distribution and the rate of apoptosis were measured using flow cytometry. The proteins cyclin D1, ERK/pERK, caspase-3, Bax and Bcl-2 were detected using western blot analysis to elucidate the mechanism of the radiosensitization effect. MTT assay showed that flavopiridol inhibited the survival rate of Eca109 cells and the effect was dose-dependent. Its IC50 was 193.3 nmol/l. The result of the clonogenic survival revealed that flavopiridol enhanced the radiosensitivity of Eca109 cells and the sensitization enhancement ratio (SER) was 1.194 at 0.2×IC50. Moreover, we detected that the cells treated with flavorpiridol were arrested at the G2/M phase and the apoptosis caused by radiation was increased. In addition, the proteins caspase-3 and Bax in cells treated with flavopiridol were upregulated, while cyclin D1 and Bcl-2 were downregulated. In conclusion, flavopiridol may enhance the radiosensitivity of Eca109 cells and the radiosensitizing effect of flavopiridol may be mediated by decreasing the levels of the cyclin D1 protein, thus increasing the percentage of cells at G2/M phase.