Brevilin A exerts anti-colorectal cancer effects and potently inhibits STAT3 signaling invitro.

Colorectal cancer (CRC) is the third most common cause of cancer-related morbidity worldwide, with an estimated of 1.85 million new cases and 850,000 deaths every year. Nevertheless, the current treatment regimens for CRC have many disadvantages, including toxicities and off-targeted side effects. STAT3 (signal transducer and activator of transcription 3) has been considered as a promising molecular target for CRC therapy. Brevilin A, a sesquiterpene lactone compound rich in Centipedae Herba has potent anticancer effects in nasopharyngeal, prostate and breast cancer cells by inhibiting the STAT3 signaling. However, the anti-CRC effect of brevilin A and the underlying mechanism of action have not been fully elucidated. In this study, we aimed to investigate the involvement of STAT3 signaling in the anti-CRC action of brevilin A. Here, HCT-116 and CT26 cell models were used to investigate the anti-CRC effects of brevilin A in vitro. HCT-116 cells overespressing with STAT3 were used to evaluate the involvement of STAT3 signaling in the anti-CRC effect of brevilin A. Screening of 49 phosphorylated tyrosine kinases in the HCT-116 cells after brevilin A treatment was performed by using the human phospho-receptor tyrosine kinase (phospho-RTK) array. Results showed that brevilin A inhibited cell proliferation and cell viability, induced apoptosis, reduced cell migration and invasion, inhibited angiogenesis, lowered the protein expression levels of phospho-Src (Tyr416), phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), and inhibited STAT3 activation and nuclear localization. Brevilin A also significantly reduced the protein expression levels of STAT3 target genes, such as MMP-2, VEGF and Bcl-xL. More importantly, over-activation of STAT3 diminished brevilin A's effects on cell viability. All these results suggest that brevilin A exerts potent anti-CRC effects, at least in part, by inhibiting STAT3 signaling. Our findings provide a strong pharmacological basis for the future exploration and development of brevilin A as a novel STAT3-targeting phytotherapeutic agent for CRC treatment.

Brevilin A is a potent anti-metastatic CRC agent that targets the VEGF-IL6-STAT3 axis in the HSCs-CRC interplay.

BACKGROUND: More than half of the colorectal cancer (CRC) patients will develop liver metastasis that underlies the cancer mortality. In the hepatic tumor microenvironment, the interplay between CRC cells and hepatic stellate cells (HSCs), and the activation of HSCs to become carcinoma-associated fibroblasts (CAFs) will further promote the cancer development. Nevertheless, the critical signaling molecule that involved in these processes remains unknown, which hinders the development of effective therapeutic agents for the treatment of metastatic CRC (mCRC). METHODS: Conditioned medium system and co-cultured system were used to examine the interplay between CRC cells and HSCs. Luminex liquid suspension chip detection and enzyme-linked immunosorbent assay were used to screen for the mediators in the conditioned medium that facilitated the CRC-HSCs interplay and HSCs-to-CAFs differentiation. Cell and animal models were used to examine whether brevilin A inhibited CRC liver metastasis via the VEGF-IL6-STAT3 axis. RESULTS: In the CRC-HSCs interplay, CRC promoted HSCs-to-CAFs differentiation by releasing vascular endothelial growth factor (VEGF); and HSCs released interleukin 6 (IL6) that activated signal transducer and activator of transcription 3 (STAT3) in the CRC and hence increased the cancer metastatic potential. The functions of the VEGF-IL6-STAT3 axis in the HSCs-CRC interplay were further validated by VEGF recombinant protein and IL6 neutralizing antibody. More importantly, brevilin A, an active compound isolated from Centipeda minima (L.) A. Br. et Aschers, targeted the VEGF-IL6-STAT3 axis in the CRC-HSCs interplay, hence significantly inhibited colorectal liver metastasis and cancer growth both in vitro and in vivo. CONCLUSIONS: We are the first to demonstrate brevilin A possesses potent anti-mCRC effect by targeting the VEGF-IL6-STAT3 axis in the CRC-HSCs interplay. Our findings not only support the development of brevilin A as a novel therapeutic agent for mCRC treatment, but also pave the path for the development of other VEGF-IL6-STAT3 targeting therapeutic strategies.

miR-7/TGF-ß2 axis sustains acidic tumor microenvironment-induced lung cancer metastasis.

Acidosis, regardless of hypoxia involvement, is recognized as a chronic and harsh tumor microenvironment (TME) that educates malignant cells to thrive and metastasize. Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression, the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy. Here, chemical-induced and transgenic mouse models for colon, liver and lung cancer were established, respectively. miR-7 and TGF-ß2 expressions were examined in clinical tissues (n = 184). RNA-seq, miRNA-seq, proteomics, biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis. Our data show that lung cancer is sensitive to the increased acidification of TME, and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5p. TGF-ß2 is a direct target of miR-7-5p. The reduced expression of miR-7-5p subsequently increases the expression of TGF-ß2 which enhances the metastatic potential of the lung cancer. Indeed, overexpression of miR-7-5p reduces the acidic pH-enhanced lung cancer metastasis. Furthermore, the human lung tumor samples also show a reduced miR-7-5p expression but an elevated level of activated TGF-ß2; the expressions of both miR-7-5p and TGF-ß2 are correlated with patients' survival. We are the first to identify the role of the miR-7/TGF-ß2 axis in acidic pH-enhanced lung cancer metastasis. Our study not only delineates how acidification directly affects tumorigenesis, but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer (NSCLC) treatment. Our study opens an avenue to explore the pH-sensitive subcellular components as novel therapeutic targets for cancer treatment.

Centipeda minima: An update on its phytochemistry, pharmacology and safety.

ETHNOPHARMACOLOGICAL RELEVANCE: Centipeda minima (CM), the dried whole plant of Centipeda minima (L.) A. Braun and Aschers, has been used as a traditional Chinese medicinal herb for thousands of years for the treatments of rhinitis, sinusitis, cough and asthmatic diseases. This review aimed to evaluate the therapeutic potential of CM by summarizing its phytochemistry, pharmacology, clinical application and safety. METHODS: This review summarizes the published studies on CM in the Chinese Pharmacopoeia and literature databases including PubMed, Web of Science, Baidu Scholar, Wiley and China Knowledge Resource Integrated Database (CNKI), as well as the research articles on the phytochemistry, pharmacology, clinical application and safety of CM. RESULTS: A total of 191 compounds have been isolated and identified from CM, including terpenes, flavonoids, sterols, phenols, organic acids and volatile oils. In addition, the pharmacological effects of CM, such as anti-cancer, anti-inflammatory and anti-bacterial activities, have also been evaluated by both in vitro and in vivo studies. The signaling pathways and mechanisms of action underlying the anti-cancer effects of CM have been revealed. Clinical applications of CM mainly include rhinitis and sinusitis, gynecological inflammation, cough, as well as asthma. CONCLUSION: CM is a medicinal herb that possesses many therapeutic effects. Cutting-edge technology and system biology could provide us a more comprehensive understanding of the therapeutic effects, constituting components and toxicity of CM, which are the prerequisites for its translation into therapeutics for various disease treatments.

Medicinal herbs and bioactive compounds overcome the drug resistance to epidermal growth factor receptor inhibitors in non-small cell lung cancer.

Lung cancer is the leading cause of cancer-related mortality worldwide. Non-small cell lung cancer (NSCLC) accounts for ~85% of all lung cancer cases. Patients harboring epidermal growth factor receptor (EGFR) mutations usually develop resistance to treatment with frontline EGFR-tyrosine kinase inhibitors (EGFR-TKIs). The present review summarizes the current findings and delineates the molecular mechanism of action for the therapeutic effects of herbal extracts and phytochemicals in overcoming EGFR-TKI resistance in NSCLC. Novel molecular targets underlying EGFR-TKI resistance in NSCLC are also discussed. This review provides valuable information for the development of herbal bioactive compounds as alternative treatments for EGFR-TKI-resistant NSCLC.

The current understanding on the impact of KRAS on colorectal cancer.

KRAS (kirsten rat sarcoma viral oncogene) is a member of the RAS family. KRAS mutations are one of most dominant mutations in colorectal cancer (CRC). The impact of KRAS mutations on the prognosis and survival of CRC patients drives many research studies to explore potential therapeutics or target therapy for the KRAS mutant CRC. This review summarizes the current understanding of the pathological consequences of the KRAS mutations in the development of CRC; and the impact of the mutations on the response and the sensitivity to the current front-line chemotherapy. The current therapeutic strategies for treating KRAS mutant CRC, the difficulties and challenges will also be discussed.

Berberine and cinnamaldehyde together prevent lung carcinogenesis.

Starving tumor cells by restricting nutrient sources is a promising strategy for combating cancer. Because both berberine and cinnamaldehyde can activate AMP-activated protein kinase (AMPK, a sensor of cellular energy status), we investigated whether the combination of berberine and cinnamaldehyde could synergistically prevent lung carcinogenesis through tumor cell starvation. Urethane treatment induced lung carcinogenesis in mice, downregulated AMPK and mammalian target of rapamycin (mTOR) while upregulating aquaporin-1 (AQP-1) and nuclear factor kappa B (NF-κB). Together, berberine and cinnamaldehyde reduced mouse susceptibility to urethane-induced lung carcinogenesis, and reversed the urethane-induced AMPK, mTOR, AQP-1, and NF-κB expression patterns. In vitro, berberine and cinnamaldehyde together induced A549 cell apoptosis, prevented cell proliferation, autophagy, and wound healing, upregulated AMPK, and downregulated AQP-1. The effects of the combined treatment were reduced by rapamycin (a mTOR inhibitor) or HgCL2 (an AQP inhibitor), but not Z-VAD-FMK (a caspase inhibitor). The berberine/cinnamaldehyde combination also prevented A549 cell substance permeability and decreased intracellular ATP concentrations. These results suggest the combination of berberine and cinnamaldehyde limited both primary and adaptive nutrient acquisition by lung tumors via AMPK-reduced AQP-1 expression, which ultimately starved the tumor cells.

The optimal dose of arsenic trioxide induced opposite efficacy in autophagy between K562 cells and their initiating cells to eradicate human myelogenous leukemia.

ETHNOPHARMACOLOGICAL RELEVANCE: Arsenic trioxide (As2O3), a main component of arsenolite which is a common traditional Chinese medicine (TCM) wildly used as a therapeutic agent for more than 2400 years in china, has been accepted as a standard treatment for the patients with acute promyelocytic leukemia (APL) based on the principle in TCM of "using a poison to fight against other poisons or malignancy illnesses". However, it remains unknown that which mechanism is actually responsible for the therapeutic effects against these blood malignancies. AIM OF THE STUDY: The purpose of this study was to explore the actual mechanism that ATO exerts its effects in K562 cells and their initiating cells (K562s). MATERIALS AND METHODS: K562s cells were separated and enriched for CD34+/CD38- cells using magnetic microbeads. Cell proliferation was determined by incorporation of BrdU. Cell apoptosis was evaluated by Annexin-V binding and PI uptake. Autophagy was estimated by acridine orange and immunofluorescence staining of LC3-B and p62. MC colonic formation was used to examine cell self-renew. ROS generation inside living cells was measured by DCFH-DA. Cell differentiation was assessed by the benzidine staining. The SA-ß-gal assay was used to detect cell senescence. Protein expression was examined by western blotting and immunohistochemical staining. RESULTS: K562s cells were stronger in self-renew and resistance to ATO cytotoxicity and starvation-induced apoptosis than K562 cells. Unexpectedly, we found that ATO at a dose of 0.5µM which had no effect on cell proliferation resulted in maximum suppression on self-renew in both cells and maximum starvation-induced apoptosis in K562s cells but minimum starvation-induced apoptosis in K562 cells. Next, we found that ATO no more than 0.5µM selectively induced K562s cell differentiation indicated by benzidine staining, γ-globin and CD235a expression. More importantly, we found that ATO no more than 0.5µM led to opposite efficacy in autophagy between K562 and K562s cells, and the opposite autophagy could induced late-phase senescence in both cells. Finally, we used the optimal dose of ATO to eradicate leukemia cells and obtained a satisfied therapeutic outcomes in vivo. CONCLUSIONS: Our results suggest that the used dose of ATO may determine the fate of cell differentiation senescence or malignant transformation, and the optimal dose of ATO induced opposite efficacy in autophagy between K562 cells and their initiating cells and ultimately leads both cells to late-phase senescence.

Oral kanglaite injection (KLTI) attenuates the lung cancer-promoting effect of high-fat diet (HFD)-induced obesity.

Obesity is a risk factor for cancer and cancer-related mortality, however, its role in lung cancer progression remains controversial. This study aimed to assess whether high-fat diet (HFD)-induced obesity promotes lung cancer progression and whether the promotion can be decreased by Kanglaite injection (KLTI). In vivo, HFD-induced overweight or obesity increases the lung carcinoma incidence and multiplicity in a urethane-induced lung carcinogenic model and cancer-related mortality in a LLC allograft model by increasing oxidative stress and cellular signaling molecules including JAK, STAT3, Akt, mTOR, NF-κB and cyclin D1. These changes resulted in increases in vascular disruption and the lung water content, thereby promoting lung epithelial proliferation and the epithelial-mesenchymal transition (EMT) during carcinogenesis. Chronic KLTI treatment substantially prevented the weight gain resulting from HFD consumption, thereby reversing the metabolic dysfunction-related physiological changes and reducing susceptibility to lung carcinogenesis. In vitro, KLTI significantly suppressed the proliferation and induced apoptosis and differentiation in 3T3-L1 preadipocyte cells and attenuated endothelial cell permeability in HUVECs. Our study indicates that there is a potential relationship between obesity and lung cancer. This is the first study to show that obesity can directly accelerate carcinogen-induced lung cancer progression and that KLTI can decrease the lung cancer-promoting effect of HFD-induced obesity.

Gingerol Reverses the Cancer-Promoting Effect of Capsaicin by Increased TRPV1 Level in a Urethane-Induced Lung Carcinogenic Model.

Both gingerol and capsaicin are agonists of TRPV1, which can negatively control tumor progression. This study observed the long-term effects of oral administration of 6-gingerol alone or in combination with capsaicin for 20 weeks in a urethane-induced lung carcinogenic model. We showed that lung carcinoma incidence and multiplicity were 70% and 21.2 ± 3.6, respectively, in the control versus 100% and 35.6 ± 5.2 in the capsaicin group (P < 0.01) and 50% and 10.8 ± 3.1 in the 6-gingerol group (P < 0.01). The combination of 6-gingerol and capsaicin reversed the cancer-promoting effect of capsaicin (carcinoma incidence of 100% versus 20% and multiplicity of 35.6 ± 5.2 versus 4.7 ± 2.3; P < 0.001). The cancer-promoting effect of capsaicin was due to increased epidermal growth-factor receptor (EGFR) level by decreased transient receptor potential vanilloid type-1 (TRPV1) level (P < 0.01) . The capsaicin-decreased EGFR level subsequently reduced levels of nuclear factor-κB (NF-κB) and cyclin D1 that favored enhanced lung epithelial proliferation and epithelial-mesenchymal transition (EMT) during lung carcinogenesis (P < 0.01). In contrast, 6-gingerol promoted TRPV1 level and drastically decreased the levels of EGFR, NF-κB, and cyclin D1 that favored reduced lung epithelial proliferation and EMT (P < 0.01). This study provides valuable information for the long-term consumption of chili-pepper-rich diets to decrease the risk of cancer development.

Lasting glycolytic stress governs susceptibility to urethane-induced lung carcinogenesis in vivo and in vitro.

Urethane is a recognized genotoxic carcinogen in fermented foods and beverages. This study is to compare susceptibility of ICR mice, BALB/c mice and C57BL/6 mice to urethane-induced lung carcinogenesis. The mice were injected intraperitoneally with 600 mg/kg of urethane for three times or ten times at 7-day intervals. At week 26, lung carcinogenic incidence was found in 40% ICR mice, 20% BALB/c mice and 10% C57BL/6 mice of the 3× injection group, respectively, whereas 100% lung tumor incidence took place in three mouse strains of the 10× injection group. In the 10× injection group, urethane induced lasting glycolytic stress of lung with an increase in lactate, monocarboxylate transporter 1 (MCT-1), reactive oxygen species(ROS) and 7,8-dihydro-8-oxo-29-deoxyguanosine (8-OHdG) and a decrease in pyruvate dehydrogenase (PDH) and cytochrome C oxidase (COX). In the 3× injection group, urethane also promoted lung glycolytic stress at the end of urethane injection but it lasted no more than 7 days besides in lung tumor-bearing mice. Metformin as a glycolytic enhancer promoted urethane carcinogenic efficacy in the 3× injection group, whereas 2-deoxy-glucose (2-DG) as a glycolytic inhibitor decreased urethane carcinogenic efficacy in the 10× injection group. Further, urethane promoted tumor survival in A549 cells by inducing cancer stem-like cellular state. These data suggest that lasting glycolytic stress is sufficient for urethane-induced lung tumorigenesis, and that urethane 10× injection-induced lung cancer can serve as a valuable model for lung tumor biology and tumor prevention.