Marsdenia tenacissima extract induces endoplasmic reticulum stress-associated immunogenic cell death in non-small cell lung cancer cells through targeting AXL.

ETHNOPHARMACOLOGICAL RELEVANCE: Marsdenia Tenacissima (Roxb.) Wight et Arn. is a traditional Chinese medicine. Its standardized extract (MTE), with the trade name Xiao-Ai-Ping injection, is widely used for cancer treatment. The pharmacological effects of MTE-inducing cancer cell death have been primarily explored. However, whether MTE triggers tumor endoplasmic reticulum stress (ERS)-associated immunogenic cell death (ICD) is unknown. AIM OF THE STUDY: To determine the potential role of endoplasmic reticulum stress in the anti-cancer effects of MTE, and uncover the possible mechanisms of endoplasmic reticulum stress-associated immunogenic cell death induced by MTE. MATERIAL AND METHODS: The anti-tumor effects of MTE on non-small cell lung cancer (NSCLC) were examined through CCK-8 and wound healing assay. Network pharmacology analysis and RNA-sequencing (RNA seq) were performed to confirm the biological changes of NSCLCs after MTE treatment. Western blot, qRT-PCR, reactive oxygen species (ROS) assay, and mitochondrial membrane potential (MMP) assay were used to explore the occurrence of endoplasmic reticulum stress. Immunogenic cell death-related markers were tested by ELISA and ATP release assay. Salubrinal was used to inhibit the endoplasmic reticulum stress response. SiRNA and bemcentinib (R428) were used to impede the function of AXL. AXL phosphorylation was regained by recombinant human Gas6 protein (rhGas6). The effects of MTE on endoplasmic reticulum stress and immunogenic cell death response were also proved in vivo. The AXL inhibiting compound in MTE was explored by molecular docking and confirmed by Western blot. RESULTS: MTE inhibited cell viability and migration of PC-9 and H1975 cells. Enrichment analysis identified that differential genes after MTE treatment were significantly enriched in endoplasmic reticulum stress-related biological processes. MTE decreased mitochondrial membrane potential (MMP) and increased ROS production. Meanwhile, endoplasmic reticulum stress-related proteins (ATF6, GRP-78, ATF4, XBP1s, and CHOP) and immunogenic cell death-related markers (ATP, HMGB1) were upregulated, and the AXL phosphorylation level was suppressed after MTE treatment. However, when salubrinal (an endoplasmic reticulum stress inhibitor) and MTE were co-treated cells, the inhibitory effects of MTE on PC-9 and H1975 cells were impaired. Importantly, inhibition of AXL expression or activity also promotes the expression of endoplasmic reticulum stress and immunogenic cell death-related markers. Mechanistically, MTE induced endoplasmic reticulum stress and immunogenic cell death by suppressing AXL activity, and these effects were attenuated when AXL activity recovered. Moreover, MTE significantly increased the expression of endoplasmic reticulum stress-related markers in LLC tumor-bearing mouse tumor tissues and plasma levels of ATP and HMGB1. Molecular docking illustrated that kaempferol has the strongest binding energy with AXL and suppresses AXL phosphorylation. CONCLUSION: MTE induces endoplasmic reticulum stress-associated immunogenic cell death in NSCLC cells. The anti-tumor effects of MTE are dependent upon endoplasmic reticulum stress. MTE triggers endoplasmic reticulum stress-associated immunogenic cell death by inhibiting AXL activity. Kaempferol is an active component that inhibits AXL activity in MTE. The present research revealed the role of AXL in regulating endoplasmic reticulum stress and enriched the anti-tumor mechanisms of MTE. Moreover, kaempferol may be considered a novel AXL inhibitor.

Dandelion extract inhibits triple-negative breast cancer cell proliferation by interfering with glycerophospholipids and unsaturated fatty acids metabolism.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with limited treatment options and a poor prognosis. TNBC exists widely reprogrammed lipid metabolism, and its metabolic-associated proteins and oncometabolites are promising as potential therapeutic targets. Dandelion (Taraxacum mongolicum) is a classical herbal medicine used to treat breast diseases based on traditional Chinese medicine theory and was reported to have antitumor effects and lipid regulatory capacities. Our previous study showed that dandelion extract was effective against TNBC. However, whether dandelion extract could regulate the lipid metabolisms of TNBC and exert its antitumor effects via interfering with lipids metabolism remained unclear. In this study, an integrated approach combined with network pharmacology and multi-omics techniques (including proteomics, metabolomics, and lipidomics) was performed to investigate the potential regulatory mechanisms of dandelion extract against TNBC. We first determined the antitumor effects of dandelion extract in vitro and in vivo. Then, network pharmacology analysis speculated the antitumor effects involving various metabolic processes, and the multi-omics results of the cells, tumor tissues, and plasma revealed the changes in the metabolites and metabolic-associated proteins after dandelion extract treatment. The alteration of glycerophospholipids and unsaturated fatty acids were the most remarkable types of metabolites. Therefore, the metabolism of glycerophospholipids and unsaturated fatty acids, and their corresponding proteins CHKA and FADS2, were considered the primary regulatory pathways and biomarkers of dandelion extract against TNBC. Subsequently, experimental validation showed that dandelion extract decreased CHKA expression, leading to the inhibition of the PI3K/AKT pathway and its downstream targets, SREBP and FADS2. Finally, the molecular docking simulation suggested that picrasinoside F and luteolin in dandelion extract had the most highly binding scores with CHKA, indicating they may be the potential CHKA inhibitors to regulate glycerophospholipids metabolisms of TNBC. In conclusion, we confirmed the antitumor effects of dandelion extract against TNBC cells in vitro and demonstrated that dandelion extract could interfere with glycerophospholipids and unsaturated fatty acids metabolism via downregulating the CHKA expression and inhibiting PI3K/AKT/SREBP/FADS2 axis.

Marsdenia tenacissima extract disturbs the interaction between tumor-associated macrophages and non-small cell lung cancer cells by targeting HDGF.

ETHNOPHARMACOLOGICAL RELEVANCE: Marsdenia tenacissima (Roxb.) Wight et Arn. is a traditional Chinese herbal medicine, and its water-soluble ingredient Marsdenia tenacissima extract (MTE), was widely used for cancer treatment. The multi-pharmacological efficacies and mechanisms of MTE in directly inhibiting tumor cells have been extensively studied. However, the anti-tumor effects of MTE in the tumor-associated macrophages (TAMs) microenvironment remain unclear. AIM OF THE STUDY: To uncover the role of hepatoma-derived growth factor (HDGF) in the interaction between TAMs and non-small cell lung cancer (NSCLC) cells. To evaluate the anti-tumor effects of MTE on the vicious crosstalk between TAMs and NSCLC by targeting HDGF. MATERIALS AND METHODS: HDGF-overexpression PC-9 and H292 NSCLC cell lines were constructed and verified. RNA-sequencing (RNA-seq) was performed in HDGF-overexpression PC-9 cells to probe the differential expression of genes. THP-1-derived macrophages were characterized using specific markers after stimulation with phorbol-12-myristate 13-acetate (PMA) and rhIL-4 or rhHDGF. The role of HDGF both in NSCLC cells and TAMs was determined using approaches like Western blot, qRT-PCR, ELISA, and flow cytometry. The interaction between tumor cells and TAMs were assessed by indirect co-culture H1975, PC-9 cells with M2 type macrophages. The effects of MTE on anti-tumor and macrophage polarization were evaluated in vitro and in vivo. RESULTS: RNA-seq results identified IL-4 as a critical response to HDGF in NSCLC. HDGF induced macrophages polarizing toward M2 type, and promoted NSCLC cells proliferation, migration and invasion in vitro. On the one hand, HDGF dose-dependently promoted IL-4 expression in NSCLC cells. On the other hand, HDGF induced M2 macrophage polarization through the IL-4/JAK1/STAT3 signaling pathway. MTE treatment significantly decreased the expression and secretion of HDGF in NSCLC cells. Meanwhile, MTE treatment led to M2 macrophage repolarization, as evidenced by decreased expression of M2 markers and increased levels of M1 markers. Importantly, MTE treatment significantly suppressed tumor development in C57BL/6 mice bearing Lewis lung cancer (LLC) cells in vivo, accompanied by decreased plasma HDGF levels, reduced M2 macrophages infiltration and increased M1 macrophages proportion in mice tumor tissues. CONCLUSIONS: HDGF upregulated IL-4 expression in NSCLC cells, and promoted M2 polarization by the IL-4/JAK1/STAT3 signaling pathway in macrophages. MTE disturbed the interaction between NSCLC and TAMs in vitro, and inhibited tumor growth in vivo, at least in part, by suppressing HDGF. Therefore, our present study revealed a novel anti-tumor mechanism of MTE through inhibiting HDGF expression and enhancing macrophage polarization from M2 to M1 phenotype.

Metabolic reprogramming by traditional Chinese medicine and its role in effective cancer therapy.

Metabolic reprogramming, characterized by alterations of cellular metabolic patterns, is fundamentally important in supporting the malignant behaviors of cancer cells. It is considered as a promising therapeutic target against cancer. Traditional Chinese medicine (TCM) and its bioactive components have been used in cancer therapy for an extended period, and they are well-known for their multi-target pharmacological functions and fewer side effects. However, the detailed and advanced mechanisms underlying the anticancer activities of TCM remain obscure. In this review, we summarized the critical processes of cancer cell metabolic reprogramming, including glycolysis, mitochondrial oxidative phosphorylation, glutaminolysis, and fatty acid biosynthesis. Moreover, we systemically reviewed the regulatory effects of TCM and its bioactive ingredients on metabolic enzymes and/or signal pathways that may impede cancer progress. A total of 46 kinds of TCMs was reported to exert antitumor effects and/or act as chemosensitizers via regulating metabolic processes of cancer cells, and multiple targets and signaling pathways were revealed to contribute to the metabolic-modulating functions of TCM. In conclusion, TCM has its advantages in ameliorating cancer cell metabolic reprogramming by its poly-pharmacological actions. This review may shed some new light on the explicit recognition of the mechanisms of anticancer actions of TCM, leading to the development of natural antitumor drugs based on reshaping cancer cell metabolism.

Taraxacum mongolicum extract inhibited malignant phenotype of triple-negative breast cancer cells in tumor-associated macrophages microenvironment through suppressing IL-10 / STAT3 / PD-L1 signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Triple-negative breast cancer (TNBC) is the most aggressive and the worst prognosis breast cancer with limited treatment options. Taraxacum mongolicum (also called dandelion) is a traditional Chinese medicine has been used to treat mastitis, breast abscess, and hyperplasia of mammary glands since ancient times. In modern pharmacological research, dandelion has been proven with anti-breast cancer activities. We previously reported that dandelion extract could induce apoptosis in TNBC cells. However, its anti-tumor effects and mechanisms in the tumor microenvironment have not yet been elucidated. AIM OF THE STUDY: Tumor-associated macrophages (TAMs) play an important role in regulating the interaction between tumor cells and the immune system. The present study aimed to investigate the effects and mechanisms of dandelion extract on TNBC cells under the microenvironment of TAMs, as well as its influence on the polarization of M2 macrophages. MATERIALS AND METHODS: M2 macrophages were induced by phorbol-12-myristate 13-acetate (PMA) and interleukin 4 (IL-4), and verified by flow cytometry, quantitative RT-PCR (qRT-PCR), Western blotting, and ELISA. MDA-MB-231 and MDA-MB-468 TNBC cells were co-cultured with the supernatant of M2 macrophage which providing the TAMs microenvironment. The antitumor activity of dandelion extract in TNBC cells was evaluated by MTT assay. The invasive and migratory capacity of TNBC cells was measured by transwell assays. The expression of protein and gene was assessed by Western blotting and qRT-PCR, respectively. RESULTS: TAMs microenvironment promoted the proliferation, migration, and invasion of TNBC cells. However, dandelion extract inhibited the malignant property of MDA-MB-231 and MDA-MB-468 cells induced by TAMs. Both of TAMs and IL-10 caused STAT3 activation and PD-L1 higher expression, the immunosuppressive molecules in TNBC cells, and this effect can be attenuated by IL-10 neutralizing antibody. Dandelion extract exerted inhibition on STAT3 and PD-L1 in TNBC cells under TAMs microenvironment. Furthermore, in M2 macrophages, dandelion extract remarkably promoted the expression of M1-like marker TNF-α, IL-8, and iNOS, but reduced M2-like marker IL-10, CD206, Arginase-1, and TGF-ß. CONCLUSION: Dandelion extract inhibited the proliferation, migration and invasion of TNBC cells in TAMs microenvironment through suppressing IL-10/STAT3/PD-L1 immunosuppressive signaling pathway. Furthermore, dandelion extract promoted the polarization of macrophages from M2 to M1 phenotype. Thus, our results indicated that dandelion may serve as a promising therapeutic strategy for TNBC by modulating tumor immune microenvironment.

Berberine alleviates visceral hypersensitivity in rats by altering gut microbiome and suppressing spinal microglial activation.

Accumulating evidence shows that agents targeting gut dysbiosis are effective for improving symptoms of irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. In this study we investigated the effects of berberine on the microbiota-gut-brain axis in two rat models of visceral hypersensitivity, i.e., specific pathogen-free SD rats subjected to chronic water avoidance stress (WAS) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 10 days) as well as germ-free (GF) rats subjected to fecal microbiota transplantation (FMT) from a patient with IBS (designated IBS-FMT) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 2 weeks). Before the rats were sacrificed, visceral sensation and depressive behaviors were evaluated. Then colonic tryptase was measured and microglial activation in the dorsal lumbar spinal cord was assessed. The fecal microbiota was profiled using 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. We showed that berberine treatment significantly alleviated chronic WAS-induced visceral hypersensitivity and activation of colonic mast cells and microglia in the dorsal lumbar spinal cord. Transfer of fecal samples from berberine-treated stressed donors to GF rats protected against acute WAS. FMT from a patient with IBS induced visceral hypersensitivity and pro-inflammatory phenotype in microglia, while berberine treatment reversed the microglial activation and altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. We demonstrated that berberine did not directly influence LPS-induced microglial activation in vitro. In both models, several SCFA-producing genera were enriched by berberine treatment, and positively correlated to the morphological parameters of microglia. In conclusion, activation of microglia in the dorsal lumbar spinal cord was involved in the pathogenesis of IBS caused by dysregulation of the microbiota-gut-brain axis, and the berberine-altered gut microbiome mediated the modulatory effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS.

Rhynchophylline Ameliorates Endothelial Dysfunction via Src-PI3K/Akt-eNOS Cascade in the Cultured Intrarenal Arteries of Spontaneous Hypertensive Rats.

Objectives: To examine the protective effect of Rhynchophylline (Rhy) on vascular endothelial function in spontaneous hypertensive rats (SHRs) and the underlying mechanism. Methods: Intrarenal arteries of SHRs and Wistar rats were suspended in myograph for force measurement. Expression and phosphorylation of endothelial nitric oxide (NO) synthase (eNOS), Akt, and Src kinase (Src) were examined by Western blotting. NO production was assayed by ELISA. Results: Rhy time- and concentration-dependently improved endothelium-dependent relaxation in the renal arteries from SHRs, but had no effect on endothelium-independent relaxation in SHR renal arteries. Wortmannin (an inhibitor of phosphatidylinositol 3-kinase) or PP2 (an inhibitor of Src) inhibited the improvement of relaxation in response to acetylcholine by 12 h-incubation with 300 µM Rhy. Western blot analysis revealed that Rhy elevated phosphorylations of eNOS, Akt, and Src in SHR renal arteries. Moreover, wortmannin reversed the increased phosphorylations of Akt and eNOS induced by Rhy, but did not affect the phosphorylation of Src. Furthermore, the enhanced phosphorylations of eNOS, Akt, and Src were blunted by PP2. Importantly, Rhy increased NO production and this effect was blocked by inhibition of Src or PI3K/Akt. Conclusion: The present study provides evidences for the first time that Rhy ameliorates endothelial dysfunction in SHRs through the activation of Src-PI3K/Akt-eNOS signaling pathway.

Inhibitory effect of rhynchophylline on contraction of cerebral arterioles to endothelin 1: role of rho kinase.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhynchophylline (Rhy) is a major ingredient of Uncaria rhynchophylla (UR) used to reduce blood pressure and ameliorate brain ailments. This study was to examine the role of Rho kinase (ROCK) in the inhibition of Rhy on contraction of cerebral arterioles caused by endothelin 1 (ET-1). MATERIALS AND METHODS: Cerebral arterioles of male Wistar rats were constricted with ET-1 for 10 min followed by perfusion of Rhy for 20 min. Changes in the diameters of the arterioles were recorded. The effects of Rhy on contraction of middle cerebral arteries (MCAs) were determined by a Multi-Myograph. Western blotting and immunofluorescent staining were used to examine the effects of Rhy on RhoA translocation and myosin phosphatase target subunit 1 (MYPT1) phosphorylation. RESULTS: In vivo, Rhy (30-300 µM) relaxed cerebral arterioles constricted with ET-1 dose-dependently. In vitro, Rhy at lower concentrations (1-100 µM) caused relaxation of rat MCAs constricted with KCl and Bay-K8644 (an agonist of L-type voltage-dependent calcium channels (L-VDCCs)). Rhy at higher concentrations (>100 µM) caused relaxation of rat MCAs constricted with ET-1, which was inhibited by Y27632, a ROCK׳s inhibitor. Western blotting of rat aortas showed that Rhy inhibited RhoA translocation and MYPT1 phosphorylation. Immunofluorescent staining of MCAs confirmed that phosphorylation of MYPT1 caused by ET-1 was inhibited by Rhy. CONCLUSIONS: These results demonstrate that Rhy is a potent inhibitor of contraction of cerebral arteries caused by ET-1 in vivo and in vitro. The effect of Rhy was in part mediated by inhibiting RhoA-ROCK signaling.

Long-Term Stimulation with Electroacupuncture at DU20 and ST36 Rescues Hippocampal Neuron through Attenuating Cerebral Blood Flow in Spontaneously Hypertensive Rats.

This study was designed to investigate the effect of long-term electroacupuncture at Baihui (DU20) and Zusanli (ST36) on cerebral microvessels and neurons in CA1 region of hippocampus in spontaneously hypertensive rats (SHR). A total of 45 male Wistar rats and 45 SHR were randomly grouped, with or without electroacupuncture (EA) at DU20 and ST36, once every other day for a period of 8 weeks. The mean arterial pressure (MAP) was measured once every 2 weeks. Cerebral blood flow (CBF) and the number of open microvessels in hippocampal CA1 region were detected by Laser Doppler and immunohistochemistry, respectively. Nissl staining and Western blotting were performed, respectively, to determine hippocampus morphology and proteins that were implicated in the concerning signaling pathways. The results showed that the MAP in SHR increased linearly over the observation period and was significantly reduced following electroacupuncture as compared with sham control SHR rats, while no difference was observed in Wistar rats between EA and sham control. The CBF, learning and memory capacity, and capillary rarefaction of SHR were improved by EA. The upregulation of angiotensin II type I receptor (AT1R), endothelin receptor (ETAR), and endothelin-1 (ET-1) in SHR rats was attenuated by electroacupuncture, suggesting an implication of AT1R, ETAR, and ET-1 pathway in the effect of EA.