Novel Chinese Angelica Polysaccharide Biomimetic Nanomedicine to Curcumin Delivery for Hepatocellular Carcinoma Treatment and Immunomodulatory Effect

BackgroundUsing natural polysaccharides from Traditional Chinese Medicine as nanodrug delivery systems have considerable potential for tumor diagnostics and therapeutics.PurposeOn the basis of targeted therapy and combining the advantages of natural polysaccharides (angelica polysaccharide, APS) and natural Chinese medicine (curcumin, Cur) to design functionalized nanoparticles to improve the therapeutic through cell membrane encapsulation and immunotherapy.Study Design and MethodsCur-loaded, glycyrrhetic acid (GA)-APS-disulfide bond (DTA)-Cur nanomicelle (GACS-Cur), which were prepared by the dialysis method. GACS-Cur was encapsulated with the membranes from red blood cells (RBCm) termed GACS-Cur@RBCm, which were prepared by the principle of extrusion using a miniature extruder. The developed formulations were subjected to various in vitro and in vivo evaluation tests.ResultsThe resulting APS nanocarriers supported a favorable drug-loading capacity, biocompatibility, and enhanced synergistic anti-hepatoma effects both in vitro and in vivo. After administration in mice, in vivo imaging results showed that the GACS-Cur and RBCm-coated groups had an obvious stronger tumor tissue targeting ability than the control treatment groups. Additionally, the immunomodulatory effect increased IL-12, TNF-α and IFN-γ expression and CD8+ T cell infiltration (1.9-fold) than that of the saline group. Notably, in comparison with hyaluronic acid (HA) nanocarriers, APS nanocarriers possess higher anti-hepatoma efficiency and targeting capabilities and, thus, should be further studied for a wide range of anti-cancer applications.ConclusionOur data demonstrated that APS nanocarriers encapsulated with erythrocyte membrane mighty be a promising clinical method in the development of efficacy, safety and targeting of liver cancer therapy.     

Position of lipidation influences anticancer activity of Smac analogs

A small group of lipid-conjugated Smac mimetics was synthesized to probe the influence of the position of lipidation on overall anti-cancer activity. Specifically, new compounds were modified with lipid(s) in position 3 and C-terminus. Previously described position 2 lipidated analog M11 was also synthesized. The resulting mini library of Smacs lipidated in positions 2, 3 and C-terminus was screened extensively in vitro against a total number of 50 diverse cancer cell lines revealing that both the position of lipidation as well as the type of lipid, influence their anti-cancer activity and cancer type specificity. Moreover, when used in combination therapy with inhibitor of menin–MLL1 protein interactions, position 2 modified analog SM2 showed strong synergistic anti-cancer properties. The most promising lipid-conjugated analogs SM2 and SM6, showed favorable pharmacokinetics and in vivo activity while administered subcutaneously in the preclinical mouse model. Collectively, our findings suggest that lipid modification of Smacs may be a viable approach in the development of anti-cancer therapeutic leads.     

CPT2 down-regulation promotes tumor growth and metastasis through inducing ROS/NFκB pathway in ovarian cancer

BackgroundCarnitine palmitoyltransferase 2 (CPT2) is a rate-limiting enzyme involved in fatty acid β-oxidation (FAO) regulation. Recently, it has been increasingly recognized that lipid metabolism dysregulation is closely implicated in tumorigenesis. However, the involvement of CPT2 in the progression of cancer is still largely unclear, especially in ovarian cancer (OC).MethodsIn the present study, CPT2 expression and its clinical significance were determined in OC tissues and cells. The biological functions and molecular mechanisms of CPT2 in OC growth and metastasis were determined by in vitro and in vivo assays.FindingsWe found that CPT2 was frequently down-regulated in primary ovarian serous carcinomas, which is significantly correlated with poor survival of ovarian cancer patients. Functional experiments revealed that CPT2 inhibited OC cell growth and metastasis via suppression of G1/S cell cycle transition and epithelial to mesenchymal transition (EMT), as well as induction of cell apoptosis. Mechanistically, suppression of ROS/NFκB signaling pathway by increasing fatty acid oxidation-derived NADPH production was involved in the anti-tumorigenic functions of CPT2 in OC cells.InterpretationAltogether, our findings demonstrate that CPT2 functions as a potential tumor suppressor in OC progression. CPT2 may serve as a novel prognostic marker and therapeutic target in OC.     

Manipulation of Mitophagy by “All-in-One” nanosensitizer augments sonodynamic glioma therapy

ABSTRACT

Limited penetration of chemotherapeutic drugs through the blood brain barrier (BBB), and the increased chemo-resistance of glioma cells due to macroautophagy/autophagy, result in high tumor recurrence and extremely limited survival of glioma patients. Ultrasound-targeted microbubble destruction (UTMD) is a technique of transient and reversible BBB disruption, which greatly facilitates intracerebral drug delivery. In addition, sonodynamic therapy (SDT) based on ultrasound stimulation and a sonosensitizer, can be a safe and noninvasive strategy for treating glioma. We innovatively designed a smart “all-in-one” nanosensitizer platform by incorporating the sonoactive chlorin e6 (Ce6) and an autophagy inhibitor-hydroxychloroquine (HCQ) into angiopep-2 peptide-modified liposomes (designated as ACHL), which integrates multiple diagnostic and therapeutic functions. ACHL selectively accumulated in the brain tumors during the optimal time-window of transient UTMD-mediated BBB opening. The nanosensitizer then responded to a second ultrasonic stimulation, and simultaneously unloaded HCQ and generated ROS in the glioma cells. The sonotherapy triggered apoptosis as well as MAPK/p38-PINK1-PRKN-dependent mitophagy, in which the antioxidant relieved the sonotoxicity and MAPK/p38 activation, while the inhibition of MAPK/p38 attenuated the progression toward mitophagy by compromising redistribution of PRKN. Moreover, HCQ blocking autophagosome degradation, augmented intracellular ROS production and resulted in an oxidative-damage regenerative loop. ACHL-SDT treatment using this construct significantly inhibited the xenograft-tumor growth and prolonged the survival time of tumor-bearing mice, exhibiting an improved therapeutic efficiency. All together, we demonstrated a precision sonotherapy with simultaneous apoptosis induction and mitophagy inhibition, which served as an intelligently strategic sense of working alongside, providing new insights into the theranostics of brain tumors.     

Dynamic alterations of immunosenescence-related genes in older women with breast cancer receiving chemotherapy: A prospective study

BackgroundThe exact impact of chemotherapy on the immune system of older patients with breast cancer is not well known. A longitudinal study was performed investigating the evolution of the blood immune profile during and after chemotherapy in this population.Patients and MethodsThe study included 39 patients receiving adjuvant chemotherapy (chemotherapy group, CTG) and 32 patients receiving only hormone therapy (control group, CG). A 10-gene panel associated with immunosenescence was measured in peripheral blood mononuclear cells (PBMC) before (T1), at 3 months (T2) and at 12 months (T3) after initiation of adjuvant therapy. Nutrition status was assessed by using a mini nutritional assessment scale. Linear mixed model analyses were performed for trajectory evolution, with or without adjusting for age, tumor stage, breast cancer phenotype, and/or corresponding baseline gene levels.ResultsSix genes relating to T cell activation (CD28, CD27, CD86, LCK, GRAP, LRRN3), and two genes relating to oxidative stress (PRDX6, HMOX1) exhibited a significant group-by-time effect, even after adjusting covariates(p≤ 0.01). In CTG, the T cell activation genes substantially declined from T1 to T2 and bounced back to a level higher than baseline at T3 (p<0.03), which was not observed in CG (p>0.26). Patients with malnutrition detected at T1 experienced more pronounced perturbation regarding CD27, LCK, CD69, VAMP5, and LRRN3 (p<0.05).ConclusionChemotherapy leads to transient perturbation of immune-related gene expression and potentially stimulates immunity in the long term. Well-nourished patients experience less impact of chemotherapy on immune-related gene expression profiles.     

Fe-MOF纳米探针在乳腺癌光动力增敏铁死亡及MR激活成像中实验研究

摘要 目的：探讨肿瘤酸性微环境响应铁基金属有机框架（Iron-containing Metal Organic Frameworks, Fe-MOF）纳米探针对乳腺癌光动力增敏铁死亡及其体外MR T1激活效应。方法：制备Fe-MOF纳米探针,用透射电子显微镜（Transmission Electron Microscope, TEM）及原子力显微镜（Atomic Force Microscope, AFM）对其形态进行表征;采用3,3'',5,5''-四甲基联苯胺（TMB）及5,5''-二硫双（2-硝基苯甲酸）（DTNB）评价其在溶液水平ROS生成及GSH消耗能力;通过细胞毒性实验（MTT）测定纳米探针在暗毒性及光毒性条件下对4T1乳腺癌细胞的光动力增敏铁死亡的效能;将4T1细胞与Fe-MOF共孵育后,协同激光照射处理,使用荧光显微镜观察其活性氧（Reactive Oxygen Specis, ROS）、脂质过氧化物（Lipid PerOxide, LPO）的生成以及细胞活/死染色情况;观察纳米探针在不同的pH条件下T1加权成像的激活效应,并在细胞水平测量不同时间点的T1激活效能。结果：制备的Fe-MOF纳米探针呈针状结构,厚度约为44 nm;在体外溶液水平可有效促进ROS的生成及LPO的消耗;荧光显微镜结果显示Fe-MOF触发的铁死亡效应联合光动力治疗可有效促进细胞内ROS和LPO的生成,以及肿瘤细胞死亡率升高（P<0.001）;MR成像结果显示,在酸性条件下纳米探针的T1信号可被特异性激活,pH 5.0条件下r1弛豫率为4.954 mM^-1s^-1,具有较好pH响应性及细胞水平时间依赖性激活效能。结论：pH响应诊疗一体化的Fe-MOF纳米探针可实现乳腺癌的光动力增敏铁死亡效能以及MR微环境响应激活成像。     

Decursin promotes HIF-1α proteasomal degradation and immune responses in hypoxic tumour microenvironment

BackgroundHypoxia and HIF-1α are important regulators of tumour growth and angiogenesis and could be attractive targets for cancer therapeutics. Decursin is an active compound extracted from the roots of Angelica gigas and has been shown to have potent anti-cancer and anti-angiogenic activities. However, whether decursin regulates HIF-1α activity and immune responses under hypoxic conditions is not yet understood.PurposeThe aim of this study was to identify whether decursin exhibits anti-cancer activity by targeting HIF-1α.Study designWe investigated whether decursin regulates HIF-1α protein stability and increases its degradation. In addition, we determined if decursin increases immune responses in tumour microenvironment to identify its hypoxia-associated anti-cancer activities.Materials and methodsWe performed the hypoxia-responsive element promoter–reporter assay, Western blot analysis, immune-fluorescence assay, semi-quantitative RT-PCR and ELISA for VEGF secretion, CCK-8 assay for cell proliferation, TUNEL assay for apoptosis and invasion assay in A549 human lung cancer or HCT116 human colon cancer cells. In vivo Lewis lung carcinoma (LLC) allograft mouse model was used to check tumour growth and immune responses in tumour microenvironment by immunohistochemistry analysis.ResultsWe observed that decursin inhibited HIF-1 activation under hypoxia by down-regulating the protein level of its subunit HIF-1α. It increased oxygen-dependant hydroxylation and ubiquitination of HIF-1α to promote HIF-1α degradation. Decursin also decreased mRNA expression of HIF-1α target genes. Decursin suppressed cancer cell proliferation, induced apoptosis and inhibited cancer cell invasion under hypoxia in cancer cells. In the allograft mouse tumour model, decursin reduced the hypoxic area and HIF-1α and PD-L1 expression. Infiltrating T cells (CD3+), helper T cells (CD4+) and cytotoxic (CD8+) T cells were accumulated, but regulatory T cells (Foxp3) and myeloid-derived suppressor cell-mediated immune suppressors (Arg1) were attenuated by decursin.ConclusionOur results suggest that decursin is a novel HIF-1α inhibitor that functions by promoting its proteasomal degradation and that it also helps improve T cell activation in tumour microenvironment; these findings provide new explanations about its anti-cancer and anti-angiogenic activity mechanisms.     

CD19 chimeric antigen receptor–redirected T cells combined with epidermal growth factor receptor pathway substrate 8 peptide–derived dendritic cell vaccine in leukemia

BackgroundChimeric antigen receptor (CAR)–T cell therapy opens a new era for cancer treatment. However, in prolonged follow-up, relapse has emerged as one of the major obstacles. Dendritic cell (DC) vaccination is a promising treatment to eradicate tumor cells and prevent relapse. The epidermal growth factor receptor (EGFR) pathway substrate 8 (Eps8) gene is involved in regulating cancer progression and is considered an attractive target for specific cancer immunotherapy. The purpose of this study was to explore a combinatorial therapy using CAR-T cells and a DC vaccine such as Eps8-DCs to increase leukemia treatment efficacy.MethodsWe pulsed DCs with Eps8-derived peptides to generate Eps8-DCs, engineered T cells to express a second-generation CAR specific for CD19, and analyzed the effects of the Eps8-DCs on the in vitro expansion, phenotype and effector functions of the CD19 CAR-T cells.ResultsThe Eps8-DCs significantly reduced the activation-induced cell death and enhanced the proliferative potential of CAR-T cells during in vitro expansion. In addition, the expanded T cells co-cultured with the Eps8-DCs exhibited an increased percentage of central memory T cells (Tcms) and a decreased percentage of effector memory T cells (Tems). The Eps8-DCs enhanced CD19 CAR-T cell immune functions, including cytokine production, CD107a degranulation activity and cytotoxicity.DiscussionThis study demonstrates that Eps8-DCs exert synergistic effect on CD19 targeting CAR-T cells and paves the way for clinical trials using the combination of DC vaccination and engineered T cells in relapsed leukemia.     

Targeting the NF-κB Pathway as a Combination Therapy for Advanced Thyroid Cancer

NF-κB signaling plays an important role in tumor cell proliferation, cell survival, angiogenesis, invasion, metastasis and drug/radiation resistance. Combination therapy involving NF-κB pathway inhibition is an attractive strategy for the treatment of advanced forms of thyroid cancer. This study was designed to test the efficacy of NF-κB pathway inhibition in combination with cytotoxic chemotherapy, using docetaxel and ionizing radiation in in vitro models of thyroid cancer. We found that while both docetaxel and ionizing radiation activated NF-κB signaling in thyroid cancer cells, there was no synergistic effect on cell proliferation and/or programmed cell death with either genetic (transduction of a dominant negative mutant form of IκBα) or pharmacologic (proteasome inhibitor bortezomib and IKKβ inhibitor GO-Y030) inhibition of the NF-κB pathway in thyroid cancer cell lines BCPAP, 8505C, THJ16T and SW1736. Docetaxel plus bortezomib synergistically decreased in vitro invasion of 8505C cells, but not in the other cell lines. Screening of a panel of clinically relevant targeted therapies for synergy with genetic NF-κB inhibition in a proliferation/cytotoxicity assay identified the histone deacetylase (HDAC) inhibitor suberoylanilide hydroxamic acid (SAHA) as a potential candidate. However, the synergistic effect was confirmed only in the BCPAP cells. These results indicate that NF-κB inhibitors are unlikely to be beneficial as combination therapy with taxane cytotoxic chemotherapy, external radiation therapy or radioiodine therapy. There may be unique circumstances where NF-κB inhibitors may be considered in combination with docetaxel to reduce tumor invasion or in combination with HDAC inhibitors to reduce tumor growth, but this does not appear to be a combination therapy that could be broadly applied to patients with advanced thyroid cancer. Further research may identify which subsets of patients/tumors may respond to this therapeutic approach.     

Comparison of the cytotoxic response against ovarian cancer by immune effector cells isolated and expanded from normal donors and ovarian cancer patients

Background/AimsThe aim of this study was to compare the cytotoxic response against ovarian cancer (OC) cells elicited by different immune effector cells in combination with the cytokines interleukin (IL)-2 and interferon (IFN) α-2b.MethodsOC cells were co-cultured with peripheral blood mononuclear cells (PBMC) from normal donors or OC patients and IL-2 or IFN α-2b alone or in combination, in order to determine the cytotoxicity. T cells were isolated from healthy donors to determine T cell cytotoxic activity. PBMC from healthy donors and OC patients were expanded in an IL-2/IL-7/IL-12 cocktail with and without anti-CD3 antibody, and the cytotoxic activity measured. Flow cytometry was performed on primary, selected and expanded cells to determine T, B, and natural killer- (NK) cell percentages.ResultsHealthy donor PBMC elicited a significant cytotoxic response (59%) compared with OC patient PBMC (7%). T cells enriched from normal donors elicited a significant cytotoxic response (18%) compared with controls lacking effector cells (1.4%); however, the cytotoxicity observed was significantly less compared with unselected PBMC. Expanded effector cells consisted primarily of T cells (98%) and the fold-expansion was significantly higher in the presence of anti-CD3 (19- versus 132-fold). No significant difference in the expansion (either fold-expansion or cell type) was observed between OC patients and healthy donors. Expanded cells from both healthy donors and OC patients elicited a significant cytotoxic response in the presence of IL-2 (19% and 22%) compared with controls.ConclusionsPBMC from OC patients do not elicit a significant cytotoxic response; however, ex vivo-expanded cells from OC patients are capable of cytotoxic killing similar to unexpanded T cells isolated from normal donors. These data provide the groundwork for further development of cellular therapy against OC.     

In vivo multimodal tumor imaging and photodynamic therapy with novel theranostic agents based on the porphyrazine framework-chelated gadolinium (III) cation

BackgroundA promising strategy for cancer diagnosis and therapy is the development of an agent for multimodal imaging and treatment. In the present paper we report on two novel multifunctional agents prepared on the porphyrazine pigment platform using a gadolinium (III) cation chelated by red-fluorescent tetrapyrrole macrocycles (GdPz1 and GdPz2).MethodsSpectral and magnetic properties of the compounds were analyzed. Monitoring of GdPz1 and GdPz2 accumulation in the murine colon carcinoma CT26 was performed in vivo using fluorescence imaging and MRI. The photobleaching of GdPz1 or GdPz2 and tumor growth rate after photodynamic therapy (PDT) were assessed.ResultsGdPz1 and GdPz2 demonstrated the selective accumulation in tumor that was indicated by higher fluorescence intensity in the tumor area in comparison with the normal tissues. The results of MRI in vivo showed that GdPz1 or GdPz2 provided significant contrast enhancement of the tumor in T1 MR images. PDT with GdPz2 resulted in ~ 20% decrease in fluorescence intensity of the compound and the inhibition of tumor growth.ConclusionsWe assessed the efficiency of two innovative Gd(III) cation-porphyrazine chelates as bimodal MR and fluorescent probes and photosensitizers for PDT and showed their potentials for tumor diagnostics and treatment.General significanceWater-soluble structures simple in preparation and administration into the body represent special interest for theranostics of tumors. Novel porphyrazine macrocycles chelating a central gadolinium cation demonstrated a good prospect as effective multimodal agents, representing a new approach to MRI and fluorescence imaging guided PDT.     

Synergistic breast cancer suppression efficacy of doxorubicin by combination with glycyrrhetinic acid as an angiogenesis inhibitor

BackgroundTherapeutic regimens of breast cancer treatment are increasingly inclined to adopt combination strategy based on the broad spectrum antitumor effect of doxorubicin (Dox). Currently, combination therapy comprises of conventional anti-cancer drugs and angiogenesis inhibitors have been corroborated as an effective approach in cancer treatment.PurposeWe explored the ability of a natural anti-angiogenic compound glycyrrhetinic acid (GA), derived from an edible-medicinal herb licorice, to enhance the breast cancer suppression effect of Dox.Study designThe drug ratio of GA and Dox with synergistic anticancer effect against MCF-7 cells was optimized by combination index (CI) value in vitro, followed by evaluation of the improved anticancer effects and reduced side-effects of this combination in vitro and in vivo.MethodsCell viability was measured by MTT assay. Analyses of mitochondrial membrane potential and cell apoptosis on MCF-7 cells were performed by JC-1 dye and Annexin V-FITC/PI assays. The cellular accumulation of Dox when combined with GA was evaluated. Levels of apoptosis-related proteins in MCF-7 cells were measured by Western blot analysis. Synergistic anti-angiogenic effects on HUVECs were evaluated. A breast cancer mouse model was established to investigate the anti-tumor effects in vivo.ResultsBased on the optimization by CI value, Dox and GA at 1:20 molar ratio was chosen as the optimal combination drug ratio that exhibited synergistic effect against MCF-7 breast cancer cells. In addition, the combination of GA and Dox exhibited significantly enhanced cytotoxicity, apoptosis, and loss of mitochondrial membrane potential via the upregulation of a mitochondrial-dependent apoptosis pathway against MCF-7 cells. Interestingly, the addition of GA increased the intracellular accumulation of Dox in MCF-7 cells. Moreover, VEGF-induced HUVECs proliferation, migration, and tube formation were strongly inhibited by Dox when used with GA via the significant down-regulation of VEGFR2-mediated pathway, indicating that the combination of Dox and GA could exhibit ideal synergistic anti-angiogenesis effect. Expectedly, the enhanced anti-tumor efficacy of Dox and reduced Dox-induced cardiotoxicity when used in combination with GA were evident in a mouse breast tumor model.ConclusionsThese findings support that the combination of Dox with GA is a novel and promising therapeutic strategy for the treatment of breast cancer.     

Aptamer‐conjugated mesoporous polydopamine for docetaxel targeted delivery and synergistic photothermal therapy of prostate cancer

ObjectivesIt is imperative to develop efficient strategies on the treatment of prostate cancer. Here, we constructed multifunctional nanoparticles, namely AS1411@MPDA‐DTX (AMD) for targeted and synergistic chemotherapy/photothermal therapy of prostate cancer.Materials and MethodsMesoporous polydopamine (MPDA) nanoparticles were prepared by a one‐pot synthesis method, DTX was loaded through incubation, and AS1411 aptamer was modified onto MPDA by the covalent reaction. The prepared nanoparticles were characterized by ultra‐micro spectrophotometer, Fourier transform infrared spectra, transmission electron microscope, and so on. The targeting ability was detected by selective uptake and cell killing. The mechanism of AMD‐mediated synergistic therapy was detected by Western blot and immunofluorescence.ResultsThe prepared nanoparticles can be easily synthesized and possessed excellent water solubility, stability, and controlled drug release ability, preferentially in acidic context. Based on in vitro and in vivo results, the nanoparticles can efficiently target prostate cancer cells, promote DTX internalization, and enhance the antitumor effects of chemo‐photothermal therapy strategies under the NIR laser irradiation.ConclusionsAs a multifunctional nanoplatform, AS1411@MPDA‐DTX could efficiently target prostate cancer cells, promote DTX internalization, and synergistically enhance the antiprostate cancer efficiency by combining with NIR irradiation.     

Hypericin-photodynamic therapy leads to interleukin-6 secretion by HepG2 cells and their apoptosis via recruitment of BH3 interacting-domain death agonist and caspases

Photodynamic therapy (PDT) has emerged as a capable therapeutic modality for the treatment of cancer. PDT is a targeted cancer therapy that reportedly leads to tumor cell apoptosis and/or necrosis by facilitating the secretion of certain pro-inflammatory cytokines and expression of multiple apoptotic mediators in the tumor microenvironment. In addition, PDT also triggers oxidative stress that directs tumor cell killing and activation of inflammatory responses. However, the cellular and molecular mechanisms underlying the role of PDT in facilitating tumor cell apoptosis remain ambiguous. Here, we investigated the ability of PDT in association with hypericin (HY) to induce tumor cell apoptosis by facilitating the induction of reactive oxygen species (ROS) and secretion of Th1/Th2/Th17 cytokines in human hepatocellular liver carcinoma cell line (HepG2) cells. To discover if any apoptotic mediators were implicated in the enhancement of cell death of HY-PDT-treated tumor cells, selected gene profiling in response to HY-PDT treatment was implemented. Experimental results showed that interleukin (IL)-6 was significantly increased in all HY-PDT-treated cells, especially in 1 μg/ml HY-PDT, resulting in cell death. In addition, quantitative real-time PCR analysis revealed that the expression of apoptotic genes, such as BH3-interacting-domain death agonist (BID), cytochrome complex (CYT-C) and caspases (CASP3, 6, 7, 8 and 9) was remarkably higher in HY-PDT-treated HepG2 cells than the untreated HepG2 cells, entailing that tumor destruction of immune-mediated cell death occurs only in PDT-treated tumor cells. Hence, we showed that HY-PDT treatment induces apoptosis in HepG2 cells by facilitating cytotoxic ROS, and potentially recruits IL-6 and apoptosis mediators, providing additional hints for the existence of alternative mechanisms of anti-tumor immunity in hepatocellular carcinoma, which contribute to long-term suppression of tumor growth following PDT.     

Targeted inhibition of c-MET by podophyllotoxin promotes caspase-dependent apoptosis and suppresses cell growth in gefitinib-resistant non-small cell lung cancer cells

BackgroundLung cancer has the highest incidence and cancer-related mortality of all cancers worldwide. Its treatment is focused on molecular targeted therapy. c-MET plays an important role in the development and metastasis of various human cancers and has been identified as an attractive potential anti-cancer target. Podophyllotoxin (PPT), an aryltetralin lignan isolated from the rhizomes of Podophyllum species, has several pharmacological activities that include anti-viral and anti-cancer effects. However, the mechanism of the anti-cancer effects of PPT on gefitinib-sensitive (HCC827) or -resistant (MET-amplified HCC827GR) non-small cell lung cancer (NSCLC) cells remains unexplored.PurposeIn the present study, we investigated the underlying mechanisms of PPT-induced apoptosis in NSCLC cells and found that the inhibition of c-MET kinase activity contributed to PPT-induced cell death.MethodsThe regulation of c-MET by PPT was examined by pull-down assay, ATP-competitive binding assay, kinase activity assay, molecular docking simulation, and Western blot analysis. The cell growth inhibitory effects of PPT on NSCLC cells were assessed using the MTT assay, soft agar assay, and flow cytometry analysis.ResultsPPT could directly interact with c-MET and inhibit kinase activity, which further induced the apoptosis of HCC827GR cells. In contrast, PPT did not significantly affect EGFR kinase activity. PPT significantly inhibited the cell viability of HCC827GR cells, whereas the PPT-treated HCC827 cells showed a cell viability of more than 80%. PPT dose-dependently induced G2/M cell cycle arrest, as shown by the downregulation of cyclin B1 and cdc2, and upregulation of p27 expression in HCC827GR cells. Furthermore, PPT treatment induced Bad expression and downregulation of Mcl-1, survivin, and Bcl-xl expression, subsequently activating multi-caspases. PPT thereby induced caspase-dependent apoptosis in HCC827GR cells.ConclusionThese results suggest the potential of PPT as a c-MET inhibitor to overcome tyrosine kinase inhibitor resistance in lung cancer.     

Sustained EKR inhibition by EGFR targeting therapies is a predictive factor for synergistic cytotoxicity with PDT as neoadjuvant therapy

Background

Tyrosin kinase inhibitors (TKIs) and monoclonal antibodies aimed to target epidermal growth factor receptor (EGFR) have shown limited effect as monotherapies and drug resistance is a major limitation for therapeutic success. Adjuvant therapies to EGFR targeting therapeutics are therefore of high clinical relevance.

Methods

Three EGFR targeting drugs, Cetuximab, Erlotinib and Tyrphostin AG1478 were used in combination with photodynamic therapy (PDT) in two EGFR positive cell lines, A-431 epidermoid skin carcinoma and WiDr colorectal adenocarcinoma cells. The amphiphilic meso-tetraphenylporphine with 2 sulphonate groups on adjacent phenyl rings (TPPS_2a) was utilized as a photosensitizer for PDT. The cytotoxic outcome of the combined treatments was evaluated by cell counting and MTT. Cellular signalling was explored by Western blotting.

Results

PDT as neoadjuvant to Tyrphostin in A-431 cells as well as to Tyrphostin or Erlotinib in WiDr cells revealed synergistic cytotoxicity. In contrast, Erlotinib or Cetuximab combined with neoadjuvant PDT induced an antagonistic effect on cell survival of A-431 cells. Neoadjuvant PDT and EGFR targeting therapies induced a synergistic inhibition of ERK as well as synergistic cytotoxicity only when the EGFR targeting monotherapies caused a prolonged ERK inhibition. There were no correlation between EGFR inhibition by the EGFR targeting monotherapies or the combined therapies and the cytotoxic outcome combination-therapies.

Conclusions

The results suggest that sustained ERK inhibition by EGFR targeting monotherapies is a predictive factor for synergistic cytotoxicity when combined with neoadjuvant PDT.

General significance

The present study provides a rationale for selecting anticancer drugs which may benefit from PDT as adjuvant therapy.     

Two combined photosensitizers: a goal for more effective photodynamic therapy of cancer

Photodynamic therapy (PDT) is a clinically approved therapeutic modality for the treatment of diseases characterized by uncontrolled cell proliferation, mainly cancer. It involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species upon irradiation with light, leading to tumor regression. Here a synergistic cell photoinactivation is reported based on the simultaneous administration of two PSs, zinc(II)-phthalocyanine (ZnPc) and the cationic porphyrin meso-tetrakis(4-N-methylpyridyl)porphine (TMPyP) in three cell lines (HeLa, HaCaT and MCF-7), using very low doses of PDT. We detected changes from predominant apoptosis (without cell detachment) to predominant necrosis, depending on the light dose used (2.4 and 3.6 J/cm², respectively). Analysis of changes in cytoskeleton components (microtubules and F-actin), FAK protein, as well as time-lapse video microscopy evidenced that HeLa cells were induced to undergo apoptosis, without losing adhesion to the substrate. Moreover, 24 h after intravenous injection into tumor-bearing mice, ZnPc and TMPyP were preferentially accumulated in the tumor area. PDT with combined treatment produced significant retardation of tumor growth. We believe that this combined and highly efficient strategy (two PSs) may provide synergistic curative rates regarding conventional photodynamic treatments (with one PS alone).     

Emblica officinalis Extract Induces Autophagy and Inhibits Human Ovarian Cancer Cell Proliferation,Angiogenesis, Growth of Mouse Xenograft Tumors

Patients with ovarian cancer (OC) may be treated with surgery, chemotherapy and/or radiation therapy, although none of these strategies are very effective. Several plant-based natural products/dietary supplements, including extracts from Emblica officinalis (Amla), have demonstrated potent anti-neoplastic properties. In this study we determined that Amla extract (AE) has anti-proliferative effects on OC cells under both in vitro and in vivo conditions. We also determined the anti-proliferative effects one of the components of AE, quercetin, on OC cells under in vitro conditions. AE did not induce apoptotic cell death, but did significantly increase the expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. Quercetin also increased the expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. AE also significantly reduced the expression of several angiogenic genes, including hypoxia-inducible factor 1α (HIF-1α) in OVCAR3 cells. AE acted synergistically with cisplatin to reduce cell proliferation and increase expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. AE also had anti-proliferative effects and induced the expression of the autophagic proteins beclin1 and LC3B-II in mouse xenograft tumors. Additionally, AE reduced endothelial cell antigen – CD31 positive blood vessels and HIF-1α expression in mouse xenograft tumors. Together, these studies indicate that AE inhibits OC cell growth both in vitro and in vivo possibly via inhibition of angiogenesis and activation of autophagy in OC. Thus AE may prove useful as an alternative or adjunct therapeutic approach in helping to fight OC.     

A review on pharmacological activities and synergistic effect of quercetin with small molecule agents

BackgroundQuercetin is a natural flavonoid, which widely exists in nature, such as tea, coffee, apples, and onions. Numerous studies have showed that quercetin has multiple biological activities such as anti-oxidation, anti-inflammatory, and anti-aging. Hence, quercetin has a significant therapeutic effect on cancers, obesity, diabetes, and other diseases. In the past decades, a large number of studies have shown that quercetin combined with other agents can significantly improve the overall therapeutic effect, compared to single use.PurposeThis work reviews the pharmacological activities of quercetin and its derivatives. In addition, this work also summarizes both in vivo and in vitro experimental evidence for the synergistic effect of quercetin against cancers and metabolic diseases.MethodsAn extensive systematic search for pharmacological activities and synergistic effect of quercetin was performed considering all the relevant literatures published until August 2021 through the databases including NCBI PubMed, Scopus, Web of Science, and Google Scholar. The relevant literatures were extracted from the databases with following keyword combinations: "pharmacological activities" OR "biological activities" OR "synergistic effect" OR "combined" OR "combination" AND "quercetin" as well as free-text words.ResultsQuercetin and its derivatives possess multiple pharmacological activities including anti-cancer, anti-oxidant, anti-inflammatory, anti-cardiovascular, anti-aging, and neuroprotective activities. In addition, the synergistic effect of quercetin with small molecule agents against cancers and metabolic diseases has also been confirmed.ConclusionQuercetin cooperates with agents to improve the therapeutic effect by regulating signal molecules and blocking cell cycle. Synergistic therapy can reduce the dose of agents and avoid the possible toxic and side effects in the treatment process. Although quercetin treatment has some potential side effects, it is safe under the expected use conditions. Hence, quercetin has application value and potential strength as a clinical drug. Furthermore, quercetin, as the main effective therapeutic ingredient in traditional Chinese medicine, may effectively treat and prevent coronavirus disease 2019 (COVID-19).