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

Chemical Constituents, Anti-Tumor Mechanisms, and Clinical Application: A Comprehensive Review on Scutellaria barbata

With the increasing global incidence and mortality rates of cancer, the development of novel anti-tumor drugs has become particularly urgent. Scutellaria barbata D. Don, a perennial herb belonging to the genus Scutellaria in the family Lamiaceae, has aroused extensive attention for its medicinal value in recent years. This article presents an exhaustive review of the flavonoid, diterpene, and other chemical constituents harbored within Scutellaria barbata, delving into the intricate mechanisms by which these compounds orchestrate their anti-tumor effects via diverse biological pathways. Remarkably, these compounds distinguish themselves through their capability to regulate cellular signaling, inhibit cancer cell proliferation, trigger apoptosis, disrupt angiogenesis, and bolster immune responses. These anti-tumor effects are achieved through strategic modulation of pivotal signaling cascades, particularly the PI3K/Akt/mTOR, MAPK, and NFκB pathways. In addition, this article also summarizes the clinical applications of Scutellaria barbata in tumor treatment, especially its potential in alleviating the side effects of radiotherapy and chemotherapy and improving patients' quality of life. In conclusion, this review comprehensively summarizes and analyzes the chemical constituents, anti-tumor mechanisms, and clinical applications of Scutellaria barbata, with the aim of systematically reviewing the existing research results and exploring potential future research directions.

Traditional Chinese medicine for colorectal cancer treatment: potential targets and mechanisms of action

Colorectal cancer (CRC) is a disease with complex pathogenesis, it is prone to metastasis, and its development involves abnormalities in multiple signaling pathways. Surgery, chemotherapy, radiotherapy, target therapy, and immunotherapy remain the main treatments for CRC, but improvement in the overall survival rate and quality of life is urgently needed. Traditional Chinese medicine (TCM) has a long history of preventing and treating CRC. It could affect CRC cell proliferation, apoptosis, cell cycle, migration, invasion, autophagy, epithelial-mesenchymal transition, angiogenesis, and chemoresistance by regulating multiple signaling pathways, such as PI3K/Akt, NF-κB, MAPK, Wnt/β-catenin, epidermal growth factor receptors, p53, TGF-β, mTOR, Hedgehog, and immunomodulatory signaling pathways. In this paper, the main signaling pathways and potential targets of TCM and its active ingredients in the treatment of CRC were systematically summarized, providing a theoretical basis for treating CRC with TCM and new ideas for further exploring the pathogenesis of CRC and developing new anti-CRC drugs.

Scutellaria barbata D. Don inhibits cervical cancer cell proliferation, migration, and invasion via miR-195-5p/LOXL2 axis

Background

Scutellaria barbata D. Don (SB) is a widely used herbal medicine in China, with various pharmacological effects such as anti-oxidation, anti-inflammation, and anti-cancer. This work is aimed to investigate the tumor-suppressive effect of SB in cervical cancer (CC) and to identify its underlying mechanisms.

Methods and materials

CC cell lines (HeLa and HT-3) were treated with different concentrations of SB chloroform extract (ECSB) (0, 0.2, 0.5 mg/ml). MiR-195-5p and LOXL2 mRNA expression in CC cell lines and tissue samples was detected by quantitative real-time polymerase chain reaction. Cell counting kit-8 experiment was utilized to examine cell viability; TUNEL assay and Transwell experiment was executed to examine cell apoptosis, migration, and invasion. Western blotting experiments were implemented to detect LOXL2 protein expression. Bioinformatics and dual-luciferase reporter gene experiment were executed to examine the binding relationship between miR-195-5p and LOXL2.

Results

ECSB repressed the viability, migration, and invasion of HeLa and HT-3 cells, and promoted cell apoptosis in a dose-dependent manner. MiR-195-5p was remarkably under-expressed in CC tissues and cells, and ECSB up-regulated miR-195-5p expression. MiR-195-5p inhibitors partially counteracted the suppressive effects of ECSB on the malignant phenotypes of HeLa and HT-3 cells. LOXL2 was a downstream target of miR-195-5p, and ECSB up-modulated LOXL2 expression by specifically repressing miR-195-5p.

Conclusion

SB restrains CC cell proliferation and metastasis and promotes cell apoptosis via miR-195-5p/LOXL2, which may be a potential therapeutic agent for CC treatment.

Traditional Chinese Medicines as Effective Reversals of Epithelial-Mesenchymal Transition Induced-Metastasis of Colorectal Cancer: Molecular Targets and Mechanisms

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Distant metastasis is the major cause of cancer-related mortality in patients with CRC. Epithelial-mesenchymal transition (EMT) is a critical process triggered during tumor metastasis, which is also the main impetus and the essential access within this duration. Therefore, targeting EMT-related molecular pathways has been considered a novel strategy to explore effective therapeutic agents against metastatic CRC. Traditional Chinese medicines (TCMs) with unique properties multi-target and multi-link that exert their therapeutic efficacies holistically, which could inhibit the invasion and metastasis ability of CRC cells via inhibiting the EMT process by down-regulating transforming growth factor-β (TGF-β)/Smads, PI3K/Akt, NF-κB, Wnt/β-catenin, and Notch signaling pathways. The objective of this review is to summarize and assess the anti-metastatic effect of TCM-originated bioactive compounds and Chinese medicine formulas by mediating EMT-associated signaling pathways in CRC therapy, providing a foundation for further research on the exact mechanisms of action through which TCMs affect EMT transform in CRC.

Regulation of Hedgehog Signaling by miRNAs and Nanoformulations: A Possible Therapeutic Solution for Colorectal Cancer

Hedgehog (Hh) signaling aberrations trigger differentiation and proliferation in colorectal cancer (CRC). However, the current approaches which inhibit this vital cellular pathway provoke some side effects. Therefore, it is necessary to look for new therapeutic options. MicroRNAs are small molecules that modulate expression of the target genes and can be utilized as a potential therapeutic option for CRC. On the other hand, nanoformulations have been implemented in the treatment of plethora of diseases. Owing to their excessive bioavailability, limited cytotoxicity and high specificity, nanoparticles may be considered as an alternative drug delivery platform for the Hh signaling mediated CRC. This article reviews the Hh signaling and its involvement in CRC with focus on miRNAs, nanoformulations as potential diagnostic/prognostic and therapeutics for CRC.

Effectiveness of Scutellaria barbata water extract on inhibiting colon tumor growth and metastasis in tumor-bearing mice

The plant Scutellaria barbata (SB) is commonly used as herbal medicines for treating cancer. The present pre-clinical study aimed to validate the Chinese Pharmacopoeia (CP) recommended dosages of SB water extract (SBW) in treating colon tumors. The content of chemical marker scutellarin in SBW was quantified using UPLC. Mice bearing human HCT116 xenografts or murine colon26 tumors received oral administration of SBW or scutellarin for 4 weeks. Results showed that SBW (615 and 1,230 mg/kg) and scutellarin (7 mg/kg) treatments significantly reduced human xenograft weights by 28.7, 36.9 and 28.8%, respectively. Lung metastasis area could be ameliorated after SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments by 23.4 and 29.5%, respectively. Expressions of colon cancer metastasis-related proteins E-cadherin, Tspan 8 and CXCR4, as well as Src kinase in tumors were first shown to be regulated by SBW. Furthermore, in murine colon26 tumor-bearing mice, SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments reduced the orthotopic tumor burden by 94.7% and lung metastatic tumor burden by 94.1%, respectively. Our findings provided evidences that SBW (at the mouse equivalent dosages to clinical dosages recommended by CP) could exert anti-tumor and anti-metastatic effects in colon cancer animal models.

Osteolytic metastasis in breast cancer: effective prevention strategies

INTRODUCTION

Breast cancer is the most common cancer in women throughout the world. Patients who are diagnosed early generally have better prognosis and survivability. Indeed, advanced stage breast cancer often develops osteolytic metastases, leading to bone destruction. Although there are select drugs available to treat bone metastatic disease, these drugs have shown limited success.

AREA COVERED

This paper emphasizes updated mechanisms of bone remodeling and osteolytic bone metastases of breast cancer. This article also aims to explore the potential of novel natural and synthetic therapeutics in the effective prevention of breast cancer-induced osteolysis and osteolytic metastases of breast cancer.

EXPERT OPINION

Targeting TGFβ and BMP signaling pathways, along with osteoclast activity, appears to be a promising therapeutic strategy in the prevention of breast cancer-induced osteolytic bone destruction and metastatic growth at bone metastatic niches. Pilot studies in animal models suggest various natural and synthetic compounds and monoclonal antibodies as putative therapeutics in the prevention of breast cancer stimulated osteolytic activity. However, comprehensive pre-clinical studies demonstrating the PK/PD and in-depth understanding of molecular mechanism(s) by which these potential molecules exhibit anti-tumor growth and anti-osteolytic activity are still required to develop effective therapies against breast cancer-induced osteolytic bone disease.

Chinese herbal medicines for prevention and treatment of colorectal cancer: From molecular mechanisms to potential clinical applications

Worldwide, colorectal cancer (CRC) is one of the most common malignant tumors, leading to immense social and economic burdens. Currently, the main treatments for CRC include surgery, chemotherapy, radiotherapy and immunotherapy. Despite advances in the diagnosis and treatment of CRC, the prognosis for CRC patients remains poor. Furthermore, the occurrence of side effects and toxicities severely limits the clinical use of these therapies. Therefore, alternative medications with high efficacy but few side effects are needed. An increasing number of modern pharmacological studies and clinical trials have supported the effectiveness of Chinese herbal medicines (CHMs) for the prevention and treatment of CRC. CHMs may be able to effectively reduce the risk of CRC, alleviate the adverse reactions caused by chemotherapy, and prolong the survival time of patients with advanced CRC. Studies of molecular mechanisms have provided deeper insight into the roles of molecules from CHMs in treating CRC. This paper summarizes the current understanding of the use of CHMs for the prevention and treatment of CRC, the main molecular mechanisms involved in these processes, the role of CHMs in modulating chemotherapy-induced adverse reactions, and CHM's potential role in epigenetic regulation of CRC. The current study provides beneficial information on the use of CHMs for the prevention and treatment of CRC in the clinic, and suggests novel directions for new drug discovery against CRC.

A review of the ethnopharmacology, phytochemistry, pharmacology, and quality control of Scutellaria barbata D. Don

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellaria barbata D. Don (S. barbata) is a well-known perennial herb that is used in traditional Chinese and Korean medicine. In China, it is known as Ban Zhi Lian, while in Korea, it is known as Banjiryun. In the Traditional Chinese Medicine (TCM) system, S. barbata has heat-clearing and detoxifying properties (Qingre Jiedu in Chinese).

AIM OF THE REVIEW

To provide a systematic review on current multifaceted understanding of S. barbata, with particular emphasis on the correlation between its traditional applications and pharmacological activities.

MATERIALS AND METHODS

All available S. barbata-related information from internet databases, including PubMed, Science Direct, Elsevier, China National Knowledge Internet, and Google Scholar (up to October 2018) were searched. Additional information was gathered from classical books on Chinese Herbals, Chinese Pharmacopoeia, and so on.

RESULTS

In the TCM system, S. barbata is mainly prescribed for its heat-clearing and detoxifying effects. More than 203 compounds have been isolated and identified from this herb, with neo-clerodane diterpenoids and flavonoids as the main compounds. Most neo-clerodanes have been demonstrated to have cytotoxic effects against different cancer cell types in vitro. The S. barbata extracts exhibited anti-inflammatory, anti-microbial, antitumor, and other pharmacological activities. To add, flavonoids, including wogonin, baicalein, apigenin, naringenin, and scutellarin, were identified as the key to quality control.

CONCLUSIONS

The heat-clearing effects of S. barbata could be attributed to its anti-inflammatory and hepatoprotective activities, whereas its detoxifying effects might be due to the anti-microbial functions of neo-clerodane diterpenoids and flavones. S. barbata may display anti-tumor effects and through active ingredient analysis, neo-clerodane diterpenoids are suggested to be its representative compounds. Overall, many pre-clinical studies have been conducted but very little concrete evidences are available on its specific effects, which are of therapeutic relevance.

Antitumor Effects and the Compatibility Mechanisms of Herb Pair Scleromitrion diffusum (Willd.) R. J. Wang-Sculellaria barbata D. Don

Herb pair Scleromitrion diffusum (Willd.) R. J. Wang (HD) and Scutellaria barbata D. Don (SB) has been most frequently used for cancer treatment in traditional Chinese medicine. This study aimed to explore the in vitro and in vivo antitumor effects of HD-SB extract and to elucidate the underlying compatibility mechanisms. HD, SB, and HD-SB extracts were prepared, and the components were detected by ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method. The in vitro antitumor effects of various concentrations of these extract were detected on several tumor cell lines using MTS assay. The in vivo antitumor effects were evaluated in Panc28 cells–bearing nude mice model. The compatibility mechanisms of herb pair HD-SB were evaluated based on the systems pharmacology strategy and then validated by cellular experiments. HD-SB extract was demonstrated to inhibit the proliferation of the cancer cell lines dose dependently by MTS assay. In vivo antitumor effects of HD-SB were much more potent than either of the two single herbs in Panc28 xenograft mice model. A total 29 active ingredients involved in antitumor effects were selected from HD and SB, and the “herb–composition–target–disease” network was constructed. Then, 58 cancer-related targets and 66 KEGG pathways were identified, and PTGS2-, HSP90-, EGFR-, MMP2-, PPARγ-, and GSTP-mediated pathways were predicted to be the antitumor mechanisms of HD-SB. The cellular experiments showed that HD-SB significantly induced cancer cell apoptosis, decreased p-EGFR, HSP90 and bcl-2 expressions, and increased PPARγ, bax, cleaved caspase 3, cleaved PARP, p-AKT, and p-PI3K expressions compared with HD or SB treatment. Our study showed that HD-SB inhibited tumor growth both in vitro and in vivo, which might be related with apoptosis induction via the EGFR/PPARγ/PI3K/AKT pathway.

From Scutellaria barbata to BZL101 in Cancer Patients: Phytochemistry, Pharmacology, and Clinical Evidence

Scutellaria barbata D.Don is a popular Chinese medicinal plant documented to treat cancer patients in traditional Chinese medicine (TCM). A botanical new investigational drug for breast cancer BZL101 (FDA IDN# 59521) was previously developed in the United States from the aqueous extract of the aerial parts from S. barbata. The early phase 1A and 1B clinical trials show its favorable toxicity profiles, good clinical tolerance, and promising efficacy for patients with metastatic breast cancer. To further evidence the phytopharmacology research, drug development, and anticancer use of this herb, a systematic literature review was performed herein on the phytochemistry, pharmacology, and specifically anticancer clinical evidence. A systematic review of the literature on phytochemical and pharmacological properties of the plant related to cancer treatment employed several web-based scientific databases including Wanfang (Chinese), Pubmed, Web of Science, and Elsevier. Key words included Scutellaria barbata, Ban Zhi Lian, cancer, and tumor. Based on critical quality criteria, only 8 out of 69 reports related to clinical studies of cancer patients in China. This review covered the available literature up to July 2019. The anticancer effects of S. barbata can be explained by the presence of various flavonoids and diterpenoids alkaloids. The underlying mechanisms are primarily summarized as cyclin/cyclin-dependent kinase (CDK)-modulated cell cycle arrest and mitochondria-mediated apoptotic death. The highly cancer-cell selective cytotoxicity and detoxifying effects of S. barbata contribute to a favorable clinical profile and enhanced quality of life for the cancer patient, thereby demanding further study as an adjuvant or alternative to conventional chemotherapy. The phytochemical and pharmacological studies reviewed strongly underpin a fundamental understanding of the anticancer activity of S. barbata and support ongoing clinical trials. The further safety verification and clinical trials are expected to progress S. barbata-based development to finally transform the traditional TCM herb S. barbata to the valuable anticancer drug.

Are polyphenol antioxidants at the root of medicinal plant anti-cancer success?

ETHNOPHARMACOLOGICAL RELEVANCE

Given the severe side effects associated with most of the conventional cancer medications, as well as the expanding body of evidence indicating secondary toxicity of these drugs, individuals with cancer are increasingly turning to natural alternatives. Similarly, the pharmaceutical industry is in search of natural products to treat cancer. An understanding of the specific active components in plant products with which anti-cancer efficacy is achieved is required for this research to move forward.

AIM OF THE STUDY

To integrate data from cancer-relatestudies on plant-derived products or extracts, to elucidate whether these products may have similar active ingredients and/or mechanisms of action, that can explain their efficacy. This review also includes a discussion of the methodological complexities and important considerations involved in accurate isolation and characterisation of active substances from plant material.

CONCLUSIONS

From the literature reviewed, most plant products with consistently reported anti-cancer efficacy contains high levels of polyphenols or other potent antioxidants and their mechanisms of action correlate to that reported for isolated antioxidants in the context of cancer. This suggests that natural products may indeed become the panacea against this chronic disease - either as therapeutic medicine strategy or to serve as templates for the design of novel synthetic drugs. The recommendation is made that antioxidant activity of plant actives and especially polyphenols, should be the focus of anti-cancer drug discovery initiatives. Lastly, researchers are advised to exploit current techniques of chemical compound characterisation when investigating polyphenol-rich plants to enable the easy consolidation of research findings from different laboratories.

Scutellaria: Debates on the anticancer property

The widespread use of plants as accessible anticancer agents leads to the identification of many natural source chemotherapeutic agents. Scutellaria one of the popular genus of flowering plants has been used for various human illnesses for thousands of years. Scutellaria has anti-metastatic, anti-proliferative, anti-invasion, anti-angiogenic and apoptosis effects in vitro as well as in vivo. Despite numerous reports on the cytotoxic-antitumor activity of the plant, there are still some issues need further consideration. Issues such as unjustified interpretations, lack of attention to the pharmacokinetics profile and weak study design may affect the final decision about the use of plants as anticancer agents and possibly needs reconsideration. In this review, we have summarized the potential health benefits of Scutellaria and its active components also the underlying mechanism of cytotoxicity and antitumor activity. Meanwhile we have discussed concerns may interfere with the precise conclusion.

Enhanced anticancer effects of Scutellaria barbata D. Don in combination with traditional Chinese medicine components on non-small cell lung cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Experience-based herbal medicine as a complementary to modern western medicine has triggered an array of studies in quest of novel anticancer drugs. Scutellaria barbata D. Don (SB) is commonly used to treat different types of cancers, but its molecular mechanism of action is not clearly understood. In this study, we attempted to elucidate the mode of action of a traditional Chinese medicine prescription with a total of 14 components, named Lian-Jia-San-Jie-Fang (LJSJF, in Chinese), where SB works as the "principle" against non-small cell lung cancer (NSCLC) cells.

MATERIALS AND METHODS

Four different NSCLC cell lines (A549, H460, H1650, and H1975) were used. Cytotoxicity, in vitro tumorigenicity, gene expression, and protein expression were analyzed by MTT assay, soft agar assay, real-time PCR, and Western blots, respectively.

RESULTS

Among the 14 components in LJSJF, SB was the only one to possess cytotoxic effects at its pharmacologically relevant doses. Additionally, we observed synergistically dose-dependent cytotoxic effects of SB in combination with other LJSJF components. After SB or LJSJF treatment, significant reductions in colony number and/or size were observed in A549 and H460; a notable dose-dependent decrease in EGFR was observed in A549, H460, and H1650; significant downregulation in EGFR and its downstream signaling targets mTOR and p38MAPK were also observed in A549 and H460; and p53 and p21 were significantly increased while survivin, cyclin D1, and MDM2 were significantly decreased in A549. Additionally, p53, p21, and Mettl7b were decreased, but p73 was increased in H460. Neither EGFR nor p53 was changed in H1975. Therefore, SB or LJSJF may induce cytotoxic effects by regulating multiple and/or distinct apoptotic pathways in different NSCLC cells.

CONCLUSION

LJSJF exerts more pronounced cytotoxic effects against NSCLC cells than SB does by synergistically regulating the underlining molecular mechanisms including EGFR and/or p53 signaling pathways.

Inhibition effects of total flavonoids from Sculellaria barbata D. Don on human breast carcinoma bone metastasis via downregulating PTHrP pathway

It is abundantly clear that tumor-derived parathyroid hormone-related protein (PTHrP), receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) are central contributors in promoting osteolytic process of breast carcinoma bone metastasis. Forcusing on this molecular basis, the study was undertaken to explore the inhibition effects of total flavonoids from Scutellaria barbata D. Don (TF-SB) on human breast carcinoma bone metastasis. MDA-MB-231 cells and nude mouse models of breast cancer bone metastasis were given TF-SB in different concentrations. The proliferation, migration and invasion potentials of MDA-MB-231 cells were respectively tested. The effects of TF-SB on tumor weights and bone destruction were investigated. The mRNA and protein expression of PTHrP, OPG and RANKL were assessed by qPCR and western blot analysis. In vitro, TF-SB inhibited the proliferation, migration and invasion of MDA-MB-231 cells in a dose-dependent manner. In vivo, TF-SB prevented bone metastasis of breast cancer by decreasing the number of osteoclast cells per field in a dose-dependent manner, but not affecting tumor growth or mouse survival. Molecular analysis revealed that TF-SB controled the secretion of osteolysis-related factors PTHrP and its downstream RANKL/OPG. Together, by controlling the expression of PTHrP and its downstream OPG/RANKL, TF-SB has significant inhibition effects on breast cancer bone metastasis, which indicates a new therapeutic method.

Effects of Yangzheng Sanjie Decoction-containing serum mediated by microRNA-7 on cell proliferation and apoptosis in gastric cancer

Gastric cancer (GC) is one of the most common types of cancer and a leading cause of cancer-associated mortality. MicroRNAs (miRNAs/miRs) are demonstrated to function as oncomiRs or tumor-suppressor-miRs in GC. miR-7 has been identified to be a tumor suppressor of GC by targeting epidermal growth factor receptor (EGFR). In our previous study, Yangzheng Sanjie Decoction (YZSJD), a traditional Chinese formula, was identified to be effective in alleviating the symptoms and even postponing turnover of precancerous lesions. To elucidate the mechanism of YZSJD, the present study evaluated the effects of YZSJD of the GC MKN-45 cell line and investigated the underlying molecular mechanisms using YZSJD-containing serum (YCS). The expression of miR-7 in GC, normal and adjacent tissue samples was examined. The results demonstrated that YCS inhibited proliferation by inducing cell cycle arrest at the S phase, and significantly induced apoptosis compared with the control group. miR-7 was significantly downregulated in GC tissues compared with the matched ones. Using reverse transcription-quantitative polymerase chain reaction and western blot analysis, the expression of miR-7 was inversely associated with EGFR. This indicates that YCS inhibits proliferation and induces apoptosis of GC cells mediated by miR-7 targeting EGFR, which may be one of the mechanisms whereby YZSJD exerts its effects on GC.

Chemopreventive effects of some popular phytochemicals on human colon cancer: a review

The present review summarizes (1) the epidemiology and etiology of colon cancer, (2) generalized cancer chemoprotective mechanisms, and (3) the chemopreventive properties of some popular phytochemicals as well as some phytochemicals developed by our research group recently.

The anti-cancer effects and mechanisms of Scutellaria barbata D. Don on CL1-5 lung cancer cells

Lung cancer, with a poor prognosis and resistance to chemotherapy, is the most common malignant tumor and has the highest mortality rate worldwide. Scutellaria barbata D. Don (SB), which is derived from the dried whole plant of Labiatae, is a well-known anti-inflammatory and anti-cancer herb. The aim of this study was to examine the anti-cancer effects and precise regulatory mechanisms of SB in CL1-5 lung cancer cells. In an in vitro assay, we found that the anti-tumor mechanism of SB was due to P38/SIRT1-regulated cell apoptosis through G2/M phase arrest and ER stress-, intrinsic mitochondrial-, and extrinsic FAS/FASL-mediated pathways. Autophagy also plays a key role in SB-induced CL1-5 cell cytotoxicity. In addition, SB exerts additive effects with etoposide or cisplatin in lung cancer cells. In an in vivo assay, we found that SB significantly reduces tumor size with decreased proliferation and angiogenesis, as well as increased apoptosis and autophagy in CL1-5 tumor-bearing mice. These findings provided experimental evidence for the application of SB in the treatment of lung cancer.

Scutellaria barbata D. Don inhibits migration and invasion of colorectal cancer cells via suppression of PI3K/AKT and TGF-β/Smad signaling pathways

Metastasis is one of the most aberrant behaviors of cancer cells. Patients with cancers, including colorectal cancer (CRC), have a higher risk of tumor recurrence and cancer-related mortality once metastasis is diagnosed. Existing treatment strategies fail to cure cancer mostly due to the onset of metastasis. Therefore, metastasis remains a challenge in cancer treatment. Some complementary and alternative medical therapies using traditional Chinese medicine have been demonstrated to be clinically effective in cancer treatment. Scutellaria barbata D. Don (SB) is a promising medicinal herb. It was previously reported that the ethanol extract of SB (EESB) is able to promote apoptosis, and inhibit cell proliferation and angiogenesis in human colon cancer cells. However, the anticancer effect of SB and the underlying mechanism require further investigation, particularly its role against metastasis. To further elucidate the antimetastatic effect of SB, MTT and Transwell assays were used in the present study to evaluate the effect of EESB on the proliferation, migration and invasion of the CRC cell line HCT-8. In addition, western blot analysis was performed to detect the expression of matrix metalloproteinases (MMPs), cadherins and other metastasis-associated proteins. EESB significantly reduced HCT-8 cell viability and attenuated the migration and invasion ability of HCT-8 cells in a dose-dependent manner. In addition, EESB decreased the expression of MMP-1, MMP-2, MMP-3/10, MMP-9 and MMP-13, and proteins in the phosphoinositide 3-kinase (PI3K)/AKT and transforming growth factor (TGF)-β/Smad pathways, but not the epithelial-mesenchymal transition (EMT)-related factors E-cadherin and N-cadherin. In conclusion, the results suggested that SB inhibits CRC cell metastasis via the suppression of PI3K/AKT and TGF-β/Smad signaling pathways, which may represent a mechanism by which SB exerts an anticancer effect.

Scutellaria barbata D. Don inhibits colorectal cancer growth via suppression of Wnt/β-catenin signaling pathway

OBJECTIVE

To investigate the effect of the ethanol extract of Scutellaria barbata D. Don (EESB) on colorectal cancer (CRC) growth and Wnt/β-catenin signaling pathway in vivo and in vitro.

METHODS

In vivo experiment, CRC xenograft mouse model was constructed with injection of HT-29 cells. Following xenograft implantation, twenty mice were randomly divided into EESB-treated group (n=10) and control group (n=10) by a random number table, and were given with intra-gastric administration of 2 g/kg EESB or saline, 5 days a week for 16 days, respectively. At the end of experiment, tumors were removed and weighed by electronic scales. The proliferation biomarker Ki-67 of tumor was evaluated by immunohistochemistry (IHC) assay. In vitro study, HT-29 cells were treated with 0, 0.5, 1.5, 2.5 mg/mL EESB for 24 h. At the end of the treatment, the viability and survival of HT-29 cells were determined by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay and colony formation assay, respectively. The mRNA expression of c-Myc, Survivin and adenomatous polyposis coli (APC) was examined by reverse transcription-polymerase chain reaction (RT-PCR) both in tumor tissues of CRC xenograft mice and HT-29 cells. Protein expression of c-Myc, Survivin, APC, and β-catenin as well as β-catenin phosphorylation level were evaluated by IHC assay or Western blotting.

RESULTS

EESB significantly reduced tumor weight in CRC xenografts mice, compared with the control group (P<0.05). IHC assay showed that EESB significantly inhibited protein expression of Ki-67 in tumor tissues (P<0.05). MTT assay showed that EESB significantly reduced HT-29 cell viability in a dose-dependent manner (P<0.05). Colony formation assay showed that EESB dose-dependently decreased the survival of HT-29 cells (P<0.05). In addition, RT-PCR assay showed that EESB decreased the mRNA expression of c-Myc and Survivin and increased APC expression, both in tumor tissues of CRC xenograft mice and HT-29 cells (P<0.05). IHC assay or Western blotting showed that EESB decreased protein expression of β-catenin, c-Myc and Survivin, as well as increased APC expression and β-catenin phosphorylation in tumor tissues or HT-29 cells (P<0.05).

CONCLUSIONS

EESB significantly reduced tumor growth in CRC xenografts mice, and inhibited the viability and survival of HT-29 cells. EESB could suppress the activation of the Wnt/β-catenin pathway, which might be one of the mechanisms whereby Scutellaria barbata D. Don exerts its anticancer activity.

Anticancer activities and mechanisms of heat-clearing and detoxicating traditional Chinese herbal medicine

In traditional Chinese medicine (TCM) theory, pathogenic heat and toxins, which are akin to the inflammatory factors, are the causes of cancer and could promote its virulent development. Therefore, heat-clearing and detoxicating (HCD) herbs are essential components of TCM formulas for cancer treatment. An increasing interest has been focused on the study of HCD herbs and accumulated evidences have shown that HCD herbs or HCD herbs-based formulas exhibited remarkable anticancer effects when used alone or combined with other therapeutic approaches. Some of the HCD herb-derived products have been tested in clinical trials. Studies revealed that extracts or pure compounds of the HCD herbs showed a broad anticancer spectrum against both solid and hematologic malignancies without significant toxic effects. Notably, some HCD herbs or formulas could strongly enhance the anticancer activities of chemo- or radio-therapy and alleviate their side effects. The anticancer activities of HCD herb exacts or the pure compounds were reported to be through multiple cellular or molecular mechanisms, such as induction of cancer cell apoptosis, differentiation and cell cycle arrest, inhibition of cancer cell growth, invasion and metastasis, and inhibition of tumor angiogenesis. In this review, we provide comprehensive analysis and summary of research progress and future prospects in this field to facilitate the further study and application of HCD herbs.

Hedgehog signaling pathway in colorectal cancer: function, mechanism, and therapy

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers worldwide. It is a complicated and often fatal cancer, and is related to a high disease-related mortality. Around 90% of mortalities are caused by the metastasis of CRC. Current treatment statistics shows a less than 5% 5-year survival for patients with metastatic disease. The development and metastasis of CRC involve multiple factors and mechanisms. The Hedgehog (Hh) signaling plays an important role in embryogenesis and somatic development. Abnormal activation of the Hh pathway has been proven to be related to several types of human cancers. The role of Hh signaling in CRC, however, remains controversial. In this review, we will go through previous literature on the Hh signaling and its functions in the formation, proliferation, and metastasis of CRC. We will also discuss the potential of targeting Hh signaling pathway in the treatment, prognosis, and prevention of CRC.

Chloroform fraction of Scutellaria barbata D. Don inhibits the growth of colorectal cancer cells by activating miR‑34a

Scutellaria barbata D. Don (SB) is a well known formula in traditional Chinese medicine, which exhibits potent anticancer effects on various cancers. Many miRNAs play crucial roles in the regulation of cancer, for instance, miR‑34a functions as a tumor suppressor, and is often downregulated during cancer. In this study, we investigated the role of ECSB in suppressing the growth of human colon cancer HCT‑8 cells, and whether this is mediated by regulation of miR‑34a and its downstream target genes, using real-time PCR and western blot analysis. ECSB treatment significantly inhibited the proliferation of HCT‑8 cells and promoted apoptosis in a dose-dependent manner. In addition, ECSB treatment significantly increased the level of miR‑34a expression and decreased the levels of Bcl-2, Notch1/2 and Jagged1 expression. Furthermore, knockdown of miR‑34a expression through transfection of anti-miR‑34a oligonucleotide was significantly reversed by ECSB treatment. Likewise, knockdown of miR‑34a resulted in significant upregulation of Bcl-2, Notch1/2 and Jagged1 expression, which was reversed following ECSB treatment. Therefore, this study reveals that ECSB inhibited cancer cell growth via promoting apoptosis and inhibiting proliferation, through regulation of miR‑34a. These findings further support the use of ECSB as an effective therapeutic agent against colon cancer.

Scutellaria barbata D. Don extract inhibits the tumor growth through down-regulating of Treg cells and manipulating Th1/Th17 immune response in hepatoma H22-bearing mice

BACKGROUND

Previous studies showed Scutellaria barbata D. Don extract (SBE) is a potent inhibitor in hepatoma and could improve immune function of hepatoma H22-bearing mice. However, the immunomodulatory function of SBE on the tumor growth of hepatoma remains unclear. This study aimed to investigate the anti-tumor effects of SBE on hepatoma H22-bearing mice and explore the underlying immunomodulatory function.

METHODS

The hepatoma H22-bearing mice were treated by SBE for 30 days. The effect of SBE on the proliferation of HepG2 cells in vitro, the growth of transplanted tumor, the cytotoxicity of natural killer (NK) cells in spleen, the amount of CD4⁺CD25⁺Foxp3⁺ Treg cells and Th17 cells in tumor tissue, and the levels of IL-10, TGF-β, IL-17A, IL-2, and IFN-γ in serum of the hepatoma H22-bearing mice was observered. IL-17A was injected to the SBE treated mice from day 9 post H22 inoculation to examine its effect on tumor growth.

RESULTS

SBE treatment inhibited the proliferation of HepG2 cells in vitro with a dose-dependent manner and significantly suppressed the tumor growth of hepatoma H22-bearing mice. Meanwhile, it increased NK cells' cytotoxicity in spleen, down-regulated the amount of CD4⁺CD25⁺Foxp3⁺ Treg cells and Th17 cells in tumor tissue, and decreased IL-10, TGF-β, and IL-17A levels (P < 0.01) whereas increased IL-2 and IFN-γ levels (P < 0.01) in the serum of hepatoma H22-bearing mice. Moreover, administration of recombinant mouse IL-17A reversed the anti-tumor effects of SBE.

CONCLUSION

SBE could inhibit the proliferation of HepG2 cells in vitro. Meanwhile, SBE also could inhibit the growth of H22 implanted tumor in hepatoma H22-bearing mice, and this function might be associated with immunomodulatory activity through down-regulating of Treg cells and manipulating Th1/Th17 immune response.

Prevention of azoxymethane/dextran sodium sulfate-induced mouse colon carcinogenesis by processed Aloe vera gel

The preventive effect of a processed Aloe vera gel (PAG) on colon carcinogenesis was examined using an azoxymethane (AOM)-initiated and dextran sodium sulfate (DSS)-promoted mouse colon carcinogenesis model. Oral administration of PAG (200, or 400mg/kg/day) significantly reduced the multiplicity of colonic adenomas and adenocarcinomas compared with the AOM/DSS only-treated mice. In the mice treated with 400mg/kg of PAG, adenoma and adenocarcinoma development was reduced to 80% and 60%, respectively, compared to 100% in the PAG-untreated AOM/DSS-treated mice. Western blot analysis using colon extracts showed that PAG reduced the activation of nuclear factor kappa B (NF-κB), resulting in the inhibition of inducible nitric oxide synthase and cyclooxygenase-2 expression. PAG appeared to inhibit the NF-κB activation through the activation of peroxisome proliferator-activated receptor gamma. PAG also inhibited the expression and phosphorylation of signal transducer and activator of transcription 3, which is known to connect inflammation and cancer. In addition, PAG inhibited cell cycle progression-inducing cellular factors, such as extracellular signal-regulated kinases 1/2, cyclin-dependent kinase 4, and cyclin D1. On the other hand, PAG increased the expression of Caudal-related homeobox transcription factor 2, which is known to be a tumor suppressor in colorectal cancer. These findings show that PAG suppresses colitis-related colon carcinogenesis by inhibiting both chronic inflammation and cell cycle progression in the colon.

Therapeutic targets of Traditional Chinese Medicine for colorectal cancer

OBJECTIVE

To explore the role of Traditional Chinese Medicine (TCM) in the prevention and treatment of colorectal cancer and identify possible therapeutic targets of TCM to provide clues for the use of TCM for colorectal cancer prevention and treatment in the clinic and to find novel directions for new drug discovery for colorectal cancer.

METHODS

We used PubMed and Google to search for and collect scientific publications for a full evalu- ation of current evidence in the literature indicating the potential role of Chinese herbal medicines and their respective ingredients as effective candidates for colorectal cancer prevention and treatment.

RESULTS

We extracted a detailed description of potential therapeutic Chinese herbal medicines and their constituent ingredients that target different mechanisms in colorectal cancer such as gene mutation, dysregulation of signaling pathways, metabolism disorders, and the inflammatory microenvironment, including both conventional and non-conventional approaches.

CONCLUSION

TCM may be a promising complementary and alternative therapy for the treatment of colorectal cancer.

Inductions of Caspase-, MAPK- and ROS-dependent Apoptosis and Chemotherapeutic Effects Caused by an Ethanol Extract of Scutellaria barbata D. Don in Human Gastric Adenocarcinom Cells

OBJECTIVES

The crude extracts of Scutellaria barbata D. Don (SB) have traditionally demonstrated inhibitory effects on numerous human cancers both in vitro and in vivo. Gastric cancer is one of the most common types of cancer on world. The authors investigated the effects of an ethanol extract of Scutellaria barbata D. Don (ESB) on the growth and survival of MKN-45 cells (a human gastric adenocarcinoma cell line).

METHODS

The MKN-45 cells were treated with different concentrations of ESB, and cell death was examined using an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Analyses of sub-G1 peaks, caspase-3 and -9 activities, and mitochondrial membrane depolarizations were conducted to determine the anti-cancer effects of SB on MKN-45 cells. Also, intracellular reactive oxygen species (ROS) generation was investigated.

RESULTS

ESB inhibited the growth of MKN-45 cells, caused cell cycle arrest, and increased the sub-G1 population. In addition, ESB markedly increased mitochondrial membrane depolarization and the activities of caspase-3 and -9. ESB exerted anti-proliferative effects on MKN-45 cells by modulating the mitogen-activated protein kinase (MAPK) signaling pathway and by increasing the generation of ROS. Furthermore, combinations of anti-cancer drugs plus ESB suppressed cell growth more than treatments with an agent or ESB, and this was especially true for cisplatin, etoposide, and doxorubicin.

CONCLUSION

ESB has a dose-dependent cytotoxic effect on MKN-45 cells and this is closely associated with the induction of apoptosis. ESB-induced apoptosis is mediated by mitochondria- , caspase- and MAPK dependent pathways. In addition, ESB enhances ROS generation and increases the chemosensitivity of MKN-45 cells. These results suggest that treatment with ESB can inhibit the proliferation and promote the apoptosis of human gastric adenocarcinoma cells by modulating the caspase-, MAPK- and ROS-dependent pathway.

New Potential Pharmacological Functions of Chinese Herbal Medicines via Regulation of Autophagy

Autophagy is a universal catabolic cellular process for quality control of cytoplasm and maintenance of cellular homeostasis upon nutrient deprivation and environmental stimulus. It involves the lysosomal degradation of cellular components such as misfolded proteins or damaged organelles. Defects in autophagy are implicated in the pathogenesis of diseases including cancers, myopathy, neurodegenerations, infections and cardiovascular diseases. In the recent decade, traditional drugs with new clinical applications are not only commonly found in Western medicines, but also highlighted in Chinese herbal medicines (CHM). For instance, pharmacological studies have revealed that active components or fractions from Chaihu (Radix bupleuri), Hu Zhang (Rhizoma polygoni cuspidati), Donglingcao (Rabdosia rubesens), Hou po (Cortex magnoliae officinalis) and Chuan xiong (Rhizoma chuanxiong) modulate cancers, neurodegeneration and cardiovascular disease via autophagy. These findings shed light on the potential new applications and formulation of CHM decoctions via regulation of autophagy. This article reviews the roles of autophagy in the pharmacological actions of CHM and discusses their new potential clinical applications in various human diseases.

The advantages of using traditional Chinese medicine as an adjunctive therapy in the whole course of cancer treatment instead of only terminal stage of cancer

Recent studies indicate that Traditional Chinese medicine (TCM) can play an important role in the whole course of cancer treatment such as recovery stages of post-operative, radiotherapy or chemotherapy stages instead of only terminal stage of cancer. In this review, we have summarized current evidence for using TCM as adjuvant cancer treatment in different stages of cancer lesions. Some TCMs (e.g., TJ-41, Liu-jun-zi-tang, PHY906, Coumarin, and Aescine) are capable of improving the post-operative symptoms such as fatigue, pain, appetite, diarrhea, nausea, vomiting, and lymphedema. Some TCMs (e.g., Ginseng, Huang-Qi, BanZhiLian, TJ-48, Huachansu injection, Shenqi fuzheng injection, and Kanglaite injection) in combination with chemo- or radio-therapy are capable of enhancing the efficacy of and diminishing the side effects and complications caused by chemo- and radiotherapy. Taken together, they have great advantages in terms of suppressing tumor progression, relieving surgery complications, increasing the sensitivity of chemo- and radio- therapeutics, improving an organism's immune system function, and lessening the damage caused by surgery, chemo- or radio-therapeutics. They have significant effects on relieving breast cancer-related lymphedema, reducing cancer-related fatigue and pain, improving radiation pneumonitis and gastrointestinal side effects, protecting liver function, and even ameliorating bone marrow suppression. This review of those medicines should contribute to an understanding of Chinese herbal medicines as an adjunctive therapy in the whole course of cancer treatment instead of only terminal stage of cancer, by providing useful information for development of more effective anti-cancer drugs and making more patients "survival with cancer" for a long time.

Oleanolic acid modulates multiple intracellular targets to inhibit colorectal cancer growth

Due to drug resistance and unacceptable cytotoxicity of most currently-used cancer chemotherapies, naturally occurring products have gained attention in the field of anticancer treatment. Oleanolic acid (OA) is a natural pentacyclic triterpenoic acid and a principal active compound in many medicinal herbs that have long been used to clinically treat various types of human malignancies. Using a colorectal cancer (CRC) mouse xenograft model and the cell line HT-29, we evaluated the effect of OA on tumor growth in vivo and in vitro, and investigated the underlying molecular mechanisms in the present study. We found that OA significantly inhibited tumor growth in volume and weight in CRC xenograft mice. In addition, OA treatment led to the induction of apoptosis and inhibition of cell proliferation. OA significantly reduced the expression of Bcl-2, Cyclin D1 and CKD4, whereas Bax and p21 expression was profoundly increased after OA treatment. Furthermore, OA significantly suppressed the activation of Akt, p70S6K and MAPK signalings, but promoted p53 pathway activation. Collectively, findings from this study suggest that OA possesses a broad range of anticancer effects via modulation of multiple intracellular targets.

Scutellaria barbata D. Don inhibits growth and induces apoptosis by suppressing IL-6-inducible STAT3 pathway activation in human colorectal cancer cells

One of the most critical cellular signal transduction pathways known to malfunction in colorectal cancer is the interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) pathway. Scutellaria barbata D. Don (SB) is well-known traditional medicine in China that targets STAT3 signaling, and it has long been used to treat various types of cancer; however, the precise mechanism of its antitumor activity remains largely unclear. In order to further elucidate this underlying mechanism, an ethanol extract of SB (EESB) in cancer treatment. The aim of the present study was to evaluate the effects of EESB on the IL-6-inducible STAT3 pathway. We tested the dose-response association between EESB, IL-6-induced proliferaion and apoptosis using an MTT assay, colony formation and flow cytometry analysis in vitro. In addition, caspase-9 and caspase-3 activation was determined using a colorimetric assay, the activity of IL-6-induced STAT3 pathway was evaluated using western blot analysis, and the expression levels of cyclin D1, cyclin-dependent kinase 4, Bcl2 and Bcl2-associated X were determined using reverse transcription-polymerase chain reaction and western blot analysis. In the present study it was found that EESB could significantly inhibit the IL-6-mediated increase in STAT3 phosphorylation levels and transcriptional activity in HT-29 human colon carcinoma cells, resulting in the suppression of cell proliferation and the induction of apoptosis. In addition, treatment with EESB markedly inhibited the IL-6-induced upregulation of cyclin D1 and B-cell lymphoma-2, two key target genes of the STAT3 pathway. These results suggest that treatment with EESB could effectively inhibit the proliferation and promote the apoptosis of human colon carcinoma cells via modulation of the IL-6/STAT3 signaling pathway and its target genes.

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.

Antimetastatic effects of Celastrus orbiculatus on human gastric adenocarcinoma by inhibiting epithelial-mesenchymal transition and NF-κB/snail signaling pathway

AIM OF THE STUDY

Celastrus orbiculatus has been used as a folk medicine in China for the treatment of many diseases. In the laboratory, the ethyl acetate extract of Celastrus orbiculatus (COE) displays a wide range of anticancer functions. However, the inhibition of the metastasis mechanism of COE in gastric cancer cells has not been investigated so far. The present study was undertaken to determine if the antimetastatic effects of COE were involved in inhibition of the epithelial-mesenchymal transition (EMT) of human gastric adenocarcinoma SGC-7901 cells.

METHODS

The adhesion, invasion, and migration of SGC-7901 cells were determined by COE treatment in vitro, using Matrigel-coated plate, transwell membrane chamber, and wound healing models, respectively. In vivo, the growth-inhibiting and antimetastatic effects of COE on the nude mice model of gastric cancer were tested and the mechanisms were explored. The expression of EMT markers and nuclear factor κB (NF-κB)/Snail signaling pathway were evaluated by using western blotting and immunohistochemistry.

RESULTS

Treatment with COE dose-dependently inhibited the proliferation, adhesion, invasion, and migration of SGC-7901 cells in vitro, which was realized by enhancing the expression of E-cadherin and reducing N-cadherin and vimentin expression. Moreover, COE suppressed the activation of NF-κB/Snail signaling pathway induced by tumor necrosis factor-α. In addition, COE effectively suppressed tumor growth and metastasis in the nude mice model due to reduced expression of N-cadherin, vimentin, NF-κB p65, and Snail and increased expression of E-cadherin in the tumor tissues.

CONCLUSION

Our findings provided new evidence that COE is an effective inhibitor of metastatic potential of SGC-7901 cells through suppression of EMT and NF-κB/Snail signal pathway. Based on these findings, COE may be considered a novel anticancer agent for the treatment of metastasis in gastric cancer.

Inhibition of the signal transducer and activator of transcription 3 signaling pathway by Qianliening capsules suppresses the growth and induces the apoptosis of human prostate cells

The signal transducer and activator of transcription 3 (STAT3) pathway is one of the main growth factor‑mediated signal transduction pathways and is closely associated with the occurrence and development of benign prostatic hyperplasia (BPH). Qianliening capsules (QC) have significant therapeutic effects on BPH; however, the precise mechanism underlying its anti‑BPH activity remains to be elucidated. To further elucidate the molecular mechanism of the therapeutic effect of QC on BPH, the present study used epidermal growth factor (EGF), which has a role in the pathogenesis of BPH, to stimulate the growth of human prostate WPMY‑1 cells and activate the STAT3 pathway in the WPMY‑1 cells. The cell viability was determined using an MTT assay and the cell morphology was observed by phase‑contrast microscopy. Fluorescence activated cell sorting analysis with Annexin‑V/propidium iodide (PI) staining and PI staining were performed to examine cell apoptosis and the cell cycle. The activation of caspase‑9 and ‑3 were evaluated by colorimetric assay. STAT3 phosphorylation and transcriptional activity were detected by western blot analysis and the luciferase gene reporter, respectively. The mRNA and protein expression levels of B‑cell lymhoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax), cyclin D1, cyclin‑dependent kinase 4 (CDK4) and p21 were measured by reverse transcription quantitative polymerase chain reaction and western blot analysis, respectively. In the present study, QC was found to significantly and dose‑dependently inhibit the EGF‑stimulated growth of WPMY‑1 cells, as evidenced by QC‑induced cell -morphological changes and a reduction in cell viability. In addition, QC treatment markedly induced the activation of caspase‑9 and ‑3. QC treatment also inhibited the EGF‑mediated increase of STAT3 phosphorylation levels and transcriptional activity in WPMY‑19 cells, accompanied by downregulation of the expression of Bcl‑2, cyclin D1 and CDK4 and upregulation of the expression of Bax and p21. These results suggested that QC effectively inhibited the proliferation and promoted the apoptosis of human prostate cells via modulation of the STAT3 signaling pathway and its target genes, which is likely to be one of the mechanisms underlying its activity in BPH treatment.