Fangfang Yang

Nifuroxazide induces apoptosis and impairs pulmonary metastasis in breast cancer model

Breast carcinoma is the most common female cancer with considerable metastatic potential. Signal transducers and activators of the transcription 3 (Stat3) signaling pathway is constitutively activated in many cancers including breast cancer and has been validated as a novel potential anticancer target. Here, we reported our finding with nifuroxazide, an antidiarrheal agent identified as a potent inhibitor of Stat3. The potency of nifuroxazide on breast cancer was assessed in vitro and in vivo. In this investigation, we found that nifuroxazide decreased the viability of three breast cancer cell lines and induced apoptosis of cancer cells in a dose-dependent manner. In addition, western blot analysis demonstrated that the occurrence of its apoptosis was associated with activation of cleaved caspases-3 and Bax, downregulation of Bcl-2. Moreover, nifuroxazide markedly blocked cancer cell migration and invasion, and the reduction of phosphorylated-Stat3Tyr705, matrix metalloproteinase (MMP) MMP-2 and MMP-9 expression were also observed. Furthermore, in our animal experiments, intraperitoneal administration of 50 mg/kg/day nifuroxazide suppressed 4T1 tumor growth and blocked formation of pulmonary metastases without detectable toxicity. Meanwhile, histological and immunohistochemical analyses revealed a decrease in Ki-67-positive cells, MMP-9-positive cells and an increase in cleaved caspase-3-positive cells upon nifuroxazide. Notably, nifuroxazide reduced the number of myeloid-derived suppressor cell in the lung. Our data indicated that nifuroxazide may potentially be a therapeutic agent for growth and metastasis of breast cancer.

A Novel Cinnamide YLT26 Induces Breast Cancer Cells Apoptosis via ROS- Mitochondrial Apoptotic Pathway in Vitro and Inhibits Lung Metastasis in Vivo

Background: Breast cancer is the leading cause of cancer death among women worldwide and metastasis is the major cause of treatment failure. Thus, new treatment options for breast cancer, especially, drugs which could prevent metastasis, are pressingly needed. Methods: In the present study, we designed and synthesized a novel cinnamide derivative, (E)-N-(4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl)-3-(3,4,5-trimethoxyphenyl)acrylamide (YLT26), which displayed potent inhibitory effects on breast cancer cells. The cell viability, apoptosis-inducing effect and reactive oxygen species (ROS) production were examined in 4T1 cells following treatment with YLT26. Meanwhile, apoptosis-related proteins levels were determined by western blotting. Finally, we evaluated the effects of YLT26 on breast tumor growth, lung metastases in vivo and the infiltration of myeloid-derived suppressor cells (MDSCs) in lung tissue. Results: Our results showed that the proliferation inhibitory effects of YLT26 were correlated with its apoptosis-inducing effect. Exposure to YLT26 induced mitochondrial transmembrane potential (∆Ψm) change, activated caspase-9, and downregulated the Bcl-2 expression, as well as enhanced ROS accumulation in 4T1 cells. Moreover, YLT26 significantly inhibited tumor growth without obvious side effects in the 4T1 tumor-bearing mice model. Immunohistochemistry analyze revealed YLT26 also induced apoptosis in vivo. More importantly, YLT26 also significantly inhibited lung metastases, which may be associated with the reduction of MDSCs. Conclusion: The present study suggested that YLT26 could inhibit breast cancer cells proliferation via ROS-mitochondrial apoptotic pathway, delay breast tumor progression, and suppress lung metastases by impacting on the immunologic microenvironment in vivo.

Punica granatum (pomegranate) leaves extract induces apoptosis through mitochondrial intrinsic pathway and inhibits migration and invasion in non-small cell lung cancer in vitro

Most conventional treatments on non-small cell lung carcinoma always accompany with awful side effects, and the incidence and mortality rates of this cancer are increasing rapidly worldwide. The objective of this study was to examine the anticancer effects of extract of Punica granatum (pomegranate) leaves extract (PLE) on the non-small cell lung carcinoma cell line A549, H1299 and mouse Lewis lung carcinoma cell line LL/2 in vitro, and explore its mechanisms of action. Our results have shown that PLE inhibited cell proliferation in non-small cell lung carcinoma cell line in a concentration- and time-dependent manner. Flow cytometry (FCM) assay showed that PLE affected H1299 cell survival by arresting cell cycle progression in G2/M phase in a dose-dependent manner and inducing apoptosis. Moreover, PLE could also decrease the reactive oxygen species (ROS) and the mitochondrial membrane potential (ΔYm), indicating that PLE may induce apoptosis via mitochondria-mediated apoptotic pathway. Furthermore, PLE blocked H1299 cell migration and invasion, and the reduction of matrix metalloproteinase (MMP) MMP-2 and MMP-9 expression were also observed in vitro. These results suggested that PLE could be an effective and safe chemotherapeutic agent in non-small cell lung carcinoma treatment by inhibiting proliferation, inducing apoptosis, cell cycle arrest and impairing cell migration and invasion.

Nifuroxazide exerts potent anti-tumor and anti-metastasis activity in melanoma.

Melanoma is a highly malignant neoplasm of melanocytes with considerable metastatic potential and drug resistance, explaining the need for new candidates that inhibit tumor growth and metastasis. The signal transducer and activator of the transcription 3 (Stat3) signaling pathway plays an important role in melanoma and has been validated as promising anticancer target for melanoma therapy. In this study, nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3, was evaluated for its anti-melanoma activity in vitro and in vivo. It had potent anti-proliferative activity against various melanoma cell lines and could induce G2/M phase arrest and cell apoptosis. Moreover, nifuroxazide markedly impaired melanoma cell migration and invasion by down-regulating phosphorylated-Src, phosphorylated-FAK, and expression of matrix metalloproteinase (MMP) -2, MMP-9 and vimentin. It also significantly inhibited tumor growth without obvious side effects in the A375-bearing mice model by inducing apoptosis and reducing cell proliferation and metastasis. Notably, nifuroxazide significantly inhibited pulmonary metastases, which might be associated with the decrease of myeloid-derived suppressor cells (MDSCs). These findings suggested that nifuroxazide might be a potential agent for inhibiting the growth and metastasis of melanoma.

Selective inhibition of EZH2 by ZLD1039 blocks H3K27methylation and leads to potent anti-tumor activity in breast cancer

Enhancer of zeste homolog 2 (EZH2) is a candidate oncogenic driver due to its prevalent overexpression and aberrant repression of tumor suppressor genes in diverse cancers. Therefore, blocking EZH2 enzyme activity may present a valid therapeutic strategy for the treatment of cancers with EZH2 overexpression including breast cancers. Here, we described ZLD1039 a potent, highly selective, and orally bioavailable small molecule inhibitor of EZH2, which inhibited breast tumor growth and metastasis. ZLD1039 considerably inhibited EZH2 methyltransferase activity with nanomolar potency, decreased global histone-3 lysine-27 (H3K27) methylation, and reactivated silenced tumor suppressors connected to increased survival of patients with breast cancer. Comparable to conditional silencing of EZH2, its inhibition by ZLD1039 decreased cell proliferation, cell cycle arrest, and induced apoptosis. Comparably, treatment of xenograft-bearing mice with ZLD1039 led to tumor growth regression and metastasis inhibition. These data confirmed the dependency of breast cancer progression on EZH2 activity and the usefulness of ZLD1039 as a promising treatment for breast cancer.

Lobaplatin arrests cell cycle progression, induces apoptosis and impairs migration and invasion in B16-F10 melanoma cell line in vitro

Melanoma is highly resistant to most conventional treatment, and the incidence and mortality rates are increasing rapidly worldwide. The objective of this study was to determine the anticancer effects of lobaplatin on the melanoma carcinoma cell line B16-F10 in vitro, and explored its mechanisms of action. Our results have shown that lobaplatin inhibited cell proliferation in human melanoma A375 and CHL-1 cells and murine melanoma B16-F10 cells in a concentration- and time-dependent manner. Flow cytometry assay confirmed that lobaplatin affected B16-F10 cell survival by blocking cell cycle progression in G2/M phase and inducing apoptosis in a concentration-dependent manner. In addition, the apoptosis was associated with downregulation of anti-apoptotic protein Bcl-2 while upregulation of pro-apoptotic protein Bax. Lobaplatin could also decrease the mitochondrial membrane potential, indicating that lobaplatin may induce apoptosis via mitochondria-mediated apoptotic pathway. Furthermore, lobaplatin blocked B16-F10 cell migration and invasion in vitro. These results suggested that lobaplatin could be an effective chemotherapeutic agent in melanoma treatment by inhibiting proliferation, inducing apoptosis, cell cycle arrest and blocking cell migration and invasion.

Inhibition of Stat3 signaling pathway by nifuroxazide improves antitumor immunity and impairs colorectal carcinoma metastasis

Colorectal carcinoma (CRC) is the one of the most common cancers with considerable metastatic potential, explaining the need for new drug candidates that inhibit tumor metastasis. The signal transducers and activators of the transcription 3 (Stat3) signaling pathway has an important role in CRC and has been validated as a promising anticancer target for CRC therapy. In the present study, we report our findings on nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3. Our studies showed that nifuroxazide decreased the viability of three CRC cell lines and induced apoptosis of cancer cells in a concentration-dependent manner. Moreover, western blot analysis demonstrated that the occurrence of its apoptosis was correlated with the activation of Bax and cleaved caspase-3, and decreased the expression of Bcl-2. In addition, nifuroxazide markedly impaired CRC cell migration and invasion by downregulating phosphorylated-Stat3Tyr705, and also impaired the expression of matrix metalloproteinases (MMP-2 and MMP-9). Furthermore, our studies showed that nifuroxazide also significantly inhibited the tumor metastasis in lung and abdomen metastasis models of colon cancer. Meanwhile, nifuroxazide functionally reduced the proliferation index, induced tumor apoptosis and impaired metastasis. Notably, nifuroxazide reduced the number of myeloid-derived suppressor cells in the blood, spleens and tumors, accompanied by the increased infiltration of CD8+ T cells in the tumors. Importantly, a marked decrease in the number of M2-type macrophages in tumor in the abdomen metastasis model was also observed. Taken together, our results indicated that nifuroxazide could effectively inhibit tumor metastasis by mediating Stat3 pathway and it might have a therapeutic potential for the treatment of CRC.

The extract from Punica granatum (pomegranate) peel induces apoptosis and impairs metastasis in prostate cancer cells

Prostate cancer is a big threat to male for its poor prognosis and high mortality rate. Natural compounds are important resources of many anticancer drugs. Pomegranate is a kind of antioxidant-rich fruit and its peel and seed has potential anticancer activities. In this study, we aimed to investigate the effects of pomegranate peel extract (PoPx) on the apoptosis and metastasis of prostate cancer cells and the related mechanism. We found that PoPx showed growth inhibition on prostate cancer cells. Nuclei morphological and flow cytometer (FCM) analysis indicated that PoPx could induce prostate cancer apoptosis. Further investigation indicated that mitochondrial mediated intrinsic pathway is involved in the apoptosis. Exposure to PoPx led to loss of mitochondrial transmembrane potential (Δym), accumulation of reactive oxygen species (ROS). Western blot analysis showed that PoPx could increase the expression ratio of Bax/Bcl2 and activation of apoptosis executor caspase 3. Wound healing assay and transwell migration and invasion assay implied that PoPx has the potential to inhibit migration and invasion, two critical steps in prostate cancer metastasis. Downregulation of MMP2/MMP9 and upregulation of TIMP2 showed accordance with the inhibition of migration and invasion. In summary, the present data showed that PoPx could be a promising drug candidate to treat prostate cancer, showing us a better way to develop novel drugs from natural compounds.

A novel benzothiazole derivative SKLB826 inhibits human hepatocellular carcinoma growth via inducing G2/M phase arrest and apoptosis

Hepatocellular carcinoma is the fifth most common cancer and durable responses in conventional treatments are limited so researchers have been devoted to developing new anti-HCC agents. Benzothiazole derivatives are known for various biological activities and have received considerable attention in cancer therapy, hence we designed and synthesized a novel potent benzothiazole compound 2-chloro-N-(2-(2-(2-morpholino-2-oxoethyl)thio)-2,3-dihydrobenzo[d]thiazol-6-yl)acetamide (SKLB826) and further investigated the biological activities against cancer. The results suggested that SKLB826 showed growth inhibition against a broad spectrum of human cancer cells, especially human HCC cell lines, in a dose-dependent manner and induced G2/M phase arrest via down-regulating the CDK1, cyclinA2 and cdc25c protein levels. SKLB826 could also induce apoptosis of HCC cells via decreasing the expression of Bcl-2 and increasing the levels of BAX and cleaved caspase-3, 9. Moreover, after treatment with SKLB826, the change of ROS level and ΔΨm suggested that SKLB826 might induce apoptosis through an intrinsic mitochondrial apoptotic pathway. Furthermore, SKLB826 could suppress tumor growth in the HepG2 xenograft model without inducing any notable major organ-related toxicity, suggesting that SKLB826 may be a potential candidate for HCC therapy.

Betulinic acid impairs metastasis and reduces immunosuppressive cells in breast cancer models

Breast cancer is the most common female cancer with considerable metastatic potential, explaining the need for new candidates that inhibit tumor metastasis. In our study, betulinic acid (BA), a kind of pentacyclic triterpenoid compound derived from birch trees, was evaluated for its anti-metastasis activity in vitro and in vivo. BA decreased the viability of three breast cancer cell lines and markedly impaired cell migration and invasion. In addition, BA could inhibit the activation of stat3 and FAK which resulted in a reduction of matrix metalloproteinases (MMPs), and increase of the MMPs inhibitor (TIMP-2) expression. Moreover, in our animal experiment, intraperitoneal administration of 10 mg/kg/day BA suppressed 4T1 tumor growth and blocked formation of pulmonary metastases without obvious side effects. Furthermore, histological and immunohistochemical analyses showed a decrease in MMP-9 positive cells, MMP-2 positive cells and Ki-67 positive cells and an increase in cleaved caspase-3 positive cells upon BA administration. Notably, BA reduced the number of myeloid-derived suppressor cells (MDSCs) in the lungs and tumors. Interestingly, in our caudal vein model, BA also obviously suppressed 4T1 tumor pulmonary metastases. These findings suggested that BA might be a potential agent for inhibiting the growth and metastasis of breast cancer.