Hedyotis diffusa Willd inhibits colorectal cancer growth in vivo via inhibition of STAT3 signaling pathway

Meta-Analysis of Oxaliplatin-Based Chemotherapy Combined With Traditional Medicines for Colorectal Cancer: Contributions of Specific Plants to Tumor Response

This meta-analysis evaluates the clinical evidence for the addition of traditional medicines (TMs) to oxaliplatin-based regimens for colorectal cancer (CRC) in terms of tumor response rate (TRR). Eight electronic databases were searched for randomized controlled trials of oxaliplatin-based chemotherapy combined with TMs compared to the same oxaliplatin-based regimen. Data on TRR from 42 randomized controlled trials were analyzed using Review Manager 5.1. Studies were conducted in China or Japan. Publication bias was not evident. The meta-analyses suggest that the combination of the TMs with oxaliplatin-based regimens increased TRR in the palliative treatment of CRC (risk ratio [RR] 1.31 [1.20-1.42], I(2) = 0%). Benefits were evident for both injection products (RR 1.36 [1.18-1.57], I(2) = 0%) and orally administered TMs (RR 1.27 [1.15-1.41], I(2) = 0%). Further sensitivity analysis of specific plant-based TMs found that Paeonia, Curcuma, and Sophora produced consistently higher contributions to the RR results. Compounds in each of these TMs have shown growth-inhibitory effects in CRC cell-line studies. Specific combinations of TMs appeared to produce higher contributions to TRR than the TMs individually. Notable among these was the combination of Hedyotis, Astragalus, and Scutellaria.

Hedyotis diffusa Willd. extract suppresses proliferation and induces apoptosis via IL-6-inducible STAT3 pathway inactivation in human colorectal cancer cells

Recent studies have indicated that the inflammatory microenvironment plays a significant role in colorectal cancer (CRC). The interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway mediates the proliferative and anti-apoptotic activities required for oncogenesis under inflammatory conditions; thus, suppressing tumor growth by targeting the IL-6/STAT3 pathway is a promising therapeutic strategy for CRC. Our previous study reported that the ethanol extract obtained from Hedyotis diffusa Willd. (EEHDW) can induce apoptosis, and inhibit the proliferation of colon cancer cells and tumor angiogenesis by modulating various signaling pathways; however, less is known regarding the activity of EEHDW in a cancer-promoting inflammatory environment. Therefore, the present study investigated whether EEHDW inhibits the growth of the CRC HT-29 cell line via the IL-6/STAT3 signaling pathway. Pretreatment of HT-29 cells with IL-6 led to an increase in cell viability, colony formation and phosphorylated STAT3 (p-STAT3) expression. Treatment of these cells with EEHDW prior to IL-6 stimulation resulted in a significant reduction in the IL-6-induced phosphorylation of STAT3. In addition, EEHDW treatment significantly reduced the mRNA expression levels of cyclin D1, cyclin-dependent kinase 4 and B-cell lymphoma-2 (Bcl-2), and upregulated the expression levels of Bcl-2-associated X protein (P<0.05), which are important target genes of the IL-6/STAT3 pathway. These findings strongly indicated that EEHDW suppresses tumor cell growth and induces the apoptosis of human CRC cells via inactivation of the IL-6/STAT3 signaling pathway.

Chemical composition, antimicrobial activity against Staphylococcus aureus and a pro-apoptotic effect in SGC-7901 of the essential oil from Toona sinensis (A. Juss.) Roem. leaves

ETHNOPHARMACOLOGICAL RELEVANCE

Leaves of Toona sinensis (A. Juss.) Roem. (TSL), a popular vegetable in China, have anti-inflammatory, antidoting, and worm-killing effects and are used in folk medicine for the treatment of enteritis, dysentery, carbuncles, boils, and especially abdominal tumors. Our aim was to investigate the in vitro antimicrobial activity against Staphylococcus aureus and anticancer property of the essential oil from TSL (TSL-EO), especially the pro-apoptotic effect in SGC-7901.

MATERIALS AND METHODS

TSL-EO obtained by hydrodistillation was analyzed by GC/MS and was tested in vitro against twenty clinically isolated strains of Staphylococcus aureus (SA 1-20), which were either methicillin-sensitive Staphylococcus aureus (MSSA) or methicillin-resistant Staphylococcus aureus (MRSA) and two standard strains viz. ATCC 25923 and ATCC 43300. The anticancer activity of TSL-EO was evaluated in vitro against HepG2, SGC7901, and HT29 through MTT assay. Moreover, the apoptosis-inducing activity of TSL-EO in SGC7901 cells was determined by Hoechst 33324 staining and flow cytometry methods. Also, the apoptosis-related proteins viz. Bax, Bcl-2 and caspase-3 were detected by western-blotting.

RESULTS

GC-MS analysis showed that TSL-EO contained a high amount of sesquiterpenes (84.64%), including copaene (8.27%), β-caryophyllene (10.16%), caryophyllene (13.18%) and β-eudesmene (5.06%). TSL-EO inhibited the growth of both MSSA and MRSA, with the lowest MIC values of 0.125 and 1mg/ml, respectively. Treatment with TSL-EO for 24h could significantly suppress the viability of three different cancer cell lines (P<0.05). Furthermore, the apoptosis-inducing activity of TSL-EO in SGC7901 cells increased in a dose-dependent manner, potentially resulting from the up-regulated expression of Bax, caspase-3 and down-regulated expression of Bcl-2.

CONCLUSIONS

TSL-EO possessed antibacterial activity against Staphylococcus aureus and significant cytotoxicity against cancer cells and particularly prominent pro-apoptotic activity in SGC7901 cells. These bioactivities were probably due to the high content of sesquiterpenes. Our results suggested that TSL-EO possessed potential health benefits and could serve as a promising natural food addictive.

Scutellaria Barbata D Don Inhibits Colorectal Cancer Growth via Suppression of Multiple Signaling Pathways

The pathogenic mechanisms underlying cancer development are complex and heterogeneous, involving multiple cellular signaling transduction pathways that usually function redundantly. In addition, crosstalk between these pathways generates a complicated and robust signaling network that is regulated by compensatory mechanisms. Given the complexity of cancer pathogenesis and progression, many of the currently used antitumor agents, which typically target a single intracellular pathway, might not always be effective on complex tumor systems. Moreover, long-term use of these agents often generates drug resistance and toxicity against normal cells. Therefore, the development of novel anticancer chemotherapies is urgently needed.Scutellaria barbataD Don (SB) is a medicinal herb that has long been used in China to treat various types of cancer. We previously reported that the ethanol extract of SB (EESB) is able to induce colon cancer cell apoptosis, inhibit cell proliferation and tumor angiogenesis via modulation of several pathways, including Hedgehog, Akt, and p53. To further elucidate the precise mechanisms of SB's antitumor activity, using a colorectal cancer (CRC) mouse xenograft model in the present study, we evaluated the therapeutic efficacy and molecular mechanisms of EESB against tumor growth. We found that EESB reduced tumor volume and tumor weight but had no effect on body weight gain in CRC mice, demonstrating that EESB could inhibit colon cancer growth in vivo without apparent adverse effect. In addition, EESB treatment could significantly suppress the activation of several CRC-related pathways, including STAT3, Erk, and p38 signalings in tumor tissues, and alter the expression of multiple critical target genes such as Bcl-2, Bax, Cyclin D1, CDK4, and p21. These molecular effects lead to the induction of cancer cell apoptosis and inhibition of cell proliferation. Our findings demonstrate that SB possesses a broad range of antitumor activities because of its ability to affect multiple intracellular targets.

The IL-6/JAK/STAT3 pathway: potential therapeutic strategies in treating colorectal cancer (Review)

Among the cytokines linked to inflammation-associated cancer, interleukin (IL)-6 drives many of the cancer 'hallmarks' through downstream activation of the Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) signaling pathway. Additionally, dysregulation of the interleukin (IL)-6-mediated JAK/STAT3 signaling pathway is closely related to the development of diverse human solid tumors including colorectal cancer (CRC). On this basis, modulation of the IL-6/JAK/STAT3 signaling pathway is currently being widely explored to develop novel therapies for CRC. The present review details the mechanisms and roles of the IL-6/JAK/STAT3 pathway in CRC, describes current therapeutic strategies, and the search for potential therapeutic approaches to treat CRC.

Cancer Prevention and Therapy: Integrating Traditional Korean Medicine Into Modern Cancer Care

In spite of billions of dollars spent on cancer research each year, overall cancer incidence and cancer survival has not changed significantly in the last half century. Instead, the recent projection from the World Health Organization suggests that global cancer incidence and death is expected to double within the next decade. This requires an "out of the box" thinking approach. While traditional medicine used for thousands of years is safe and affordable, its efficacy and mechanism of action are not fully reported. Demonstrating that traditional medicine is efficacious and how it works can provide a "bed to bench" and "bench to bed" back approach toward prevention and treatment of cancer. This current review is an attempt to describe the contributions of traditional Korean medicine (TKM) to modern medicine and, in particular, cancer treatment. TKM suggests that cancer is an outcome of an imbalance of body, mind, and spirit; thus, it requires a multimodal treatment approach that involves lifestyle modification, herbal prescription, acupuncture, moxibustion, traditional exercise, and meditation to restore the balance. Old wisdoms in combination with modern science can find a new way to deal with the "emperor of all maladies."

Ursolic acid promotes colorectal cancer cell apoptosis and inhibits cell proliferation via modulation of multiple signaling pathways

The development of colorectal cancer (CRC) is strongly correlated with the aberrant activation of multiple intracellular signaling transduction cascades including STAT3, ERK, JNK and p38 pathways which usually function redundantly. In addition, crosstalk between these pathways forms a complicated signaling network that is regulated by compensatory mechanisms. Therefore, most of the currently used and single-target-based antitumor agents might not always be therapeutically effective. Moreover, long-term use of these agents often generates drug resistance. These problems highlight the urgent need for the development of novel anticancer chemotherapies. Ursolic acid (UA) is a major active compound present in many medicinal herbs that have long been used for the clinical treatment of CRC. Although previous studies have demonstrated an antitumor effect for UA, the precise mechanisms of its tumoricidal activity are not well understood. In the present study, using CRC mouse xenograft model and the HT-29 human colon carcinoma cell line, we evaluated the efficacy of UA against tumor growth in vivo and in vitro and investigated the underlying molecular mechanisms. We found that UA inhibits cancer growth without apparent toxicity. Furthermore, UA significantly suppresses the activation of several CRC-related signaling pathways and alters the expression of critical target genes. These molecular effects lead to the induction of apoptosis and inhibition of cellular proliferation. These data demonstrate that UA possesses a broad range of anticancer activities due to its ability to affect multiple intracellular targets, suggesting that UA could be a novel multipotent therapeutic agent for cancer treatment.

Nitidine chloride inhibits hepatocellular carcinoma cell growth in vivo through the suppression of the JAK1/STAT3 signaling pathway

Signal transducer and activator of transcription 3 (STAT3) is persistently activated in cancer cells and contributes to malignant progression in various types of cancer. The Janus-activated kinase (JAK) family phosphorylates STAT3 in response to stimulation by cytokines or growth factors. The JAK1-STAT3 signaling pathway plays an important role in cell proliferation and apoptosis. Nitidine chloride (NC) is a benzophenanthridine alkaloid that has been reported as an antitumor agent due to its its inhibitory effects on topoisomerase I. Using a mouse xenograft model of hepatocellular carcinoma (HCC), this study aimed to evaluate the effects of NC on tumor growth in vivo and to elucidate the underlying mechanisms. The analysis of the effects of NC on apoptosis in HCC tumor xenografts in mice was carried out by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay; the expression of Bcl-2, Bax, cyclin-dependent kinase (CDK)4, cyclin D1, p21 and proliferating cell nuclear antigen (PCNA) was analyzed by immunohistochemistry; and the protein expression of JAK1 and STAT3 was examined by western blot analysis. Our results revealed that treatment with NC decreased the tumor volume and tumor weight, suggesting that NC inhibits HCC cell growth in vivo. In addition, NC blocked the activation of JAK1-STAT3 in the tumor tissues, which in turn resulted in the induction of cancer cell apoptosis and the inhibition of proliferation. Consequently, treatment with NC downregulated the expression of cyclin D1, CDK4 and Bcl-2 and increased the level of p21 and Bax. Our data provide a molecular basis for the antitumor activity of NC.

Chemical and preclinical studies on Hedyotis diffusa with anticancer potential

This paper presents the chemical and preclinical anticancer research on Hedyotis diffusa Willd. in detail, one of the most renowned herbs often prescribed in the polyherbal formulas for cancer treatment in traditional Chinese medicine. Anthraquinones, flavonoids, and terpenoids constitute the majority of the 69 compounds that have been isolated and identified from H. diffusa. The anticancer effects of the methanolic, ethanolic, and aqueous extracts in various preclinical cancer models have been described. This review also summarized the anticancer activity of constituents of the herb and the mechanisms of action. All the studies suggest that H. diffusa has enormous potential in the therapy of cancer and warrants further chemical and pharmacological investigation.

Livistona chinensis seed suppresses hepatocellular carcinoma growth through promotion of mitochondrial-dependent apoptosis

The Livistona chinensis seed has been used for centuries to clinically treat various types of cancer. However, the precise mechanism of its anticancer activity remains to be elucidated. In the present study, we evaluated the efficacy of the ethanol extract of Livistona chinensis seed (EELC) against tumor growth using a hepatocellular carcinoma (HCC) mouse xenograft model and an HCC cell line, HepG2, and investigated the molecular mechanisms mediating its biological activities. We found that EELC inhibited HCC growth both in vivo and in vitro, without apparent signs of toxicity. In addition, EELC treatment resulted in the induction of HCC cell apoptosis. Moreover, EELC-induced apoptosis was accompanied by the loss of mitochondrial membrane potential, activation of caspase-9 and caspase-3, and increase in the pro-apoptotic Bax/Bcl-2 ratio. Our findings suggest that promotion of mitochondrial-dependent apoptosis in cancer cells may be one of the mechanisms by which the Livistona chinensis seed is effective in cancer treatment.

Hedyotis diffusa Willd extract suppresses Sonic hedgehog signaling leading to the inhibition of colorectal cancer angiogenesis

Sonic hedgehog (SHH) signaling pathway promotes the process of angiogenesis, contributing to the growth and progression of many human malignancies including colorectal cancer (CRC), which therefore has become a promising target for cancer chemotherapy. Hedyotis diffusa Willd (HDW), as a well-known traditional Chinese herbal medicine, has long been used in China for the clinic treatment of various cancers. Recently, we reported that HDW can inhibit colorectal cancer growth in vivo and in vitro via suppression of the STAT3 pathway. In addition, we demonstrated the anti-angiogenic activity of HDW in vitro. To further elucidate the mechanism of the tumoricidal activity of HDW, by using a CRC mouse xenograft model we evaluated the in vivo effect of the ethanol extract of HDW (EEHDW) on tumor angiogenesis, and investigated the underlying molecular mechanisms. We found that EEHDW could significantly reduce intratumoral microvessel density (MVD), indicating its activity of antitumor angiogenesis in vivo. EEHDW suppressed the activation of SHH signaling in CRC xenograft tumors since it significantly decreased the expression of key mediators of SHH pathway. EEHDW treatment inhibited the expression of the critical SHH signaling target gene VEGF-A as well as its specific receptor VEGFR2. Taken together, we propose for the first time that Hedyotis diffusa Willd inhibits colorectal cancer growth in vivo via inhibition of SHH-mediated tumor angiogenesis.

Pien Tze Huang inhibits the proliferation of human colon carcinoma cells by arresting G1/S cell cycle progression

Pien Tze Huang (PZH), a well-known traditional Chinese formula prescribed 450 years ago in the Ming Dynasty, has been used in China and Southeast Asia for centuries as a folk remedy for various types of cancer, including colorectal cancer (CRC). Recently, we reported that PZH is capable of inhibiting colon cancer growth both in vivo and in vitro via the promotion of apoptosis and inhibition of tumor angiogenesis. To elucidate the mechanism of the tumoricidal activity of PZH, its effect on the proliferation of human colon carcinoma Caco-2 cells was evaluated and the underlying molecular mechanism was investigated. Results showed that PZH inhibited Caco-2 cell viability and survival in a dose- and/or time-dependent manner. In addition, PZH treatment was found to block the G1/S cell cycle progression. Moreover, PZH suppressed the mRNA and protein expression of pro-proliferative Cyclin D1 and CDK4. Findings of the present study suggest that inhibition of cell proliferation via the G1/S cell cycle arrest is a potential mechanism by which PZH can be effective in the treatment of cancer.