Acetylcorynoline Induces Apoptosis and G2/M Phase Arrest through the c-Myc Signaling Pathway in Colon Cancer Cells.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide, and despite advances in treatment, survival rates are still low; therefore, the development of novel drugs is imperative. Acetylcorynoline (ACN) is derived from Corydalis ambigua Cham. et Schltdl tubers. The effect of ACN on colon cancer is still unknown. Therefore, we investigated its potential effects. Our data showed that ACN inhibited cell viability and proliferation. Moreover, ACN induced apoptosis and cell cycle arrest by inhibiting cell growth. In the present study, we hypothesized that ACN regulates c-Myc through CNOT2 or MID1IP1. ACN reduced the protein expression of oncogenic genes, decreased c-Myc half-life, and rapidly inhibited the serum stimulation response. Moreover, knockdown of CNOT2 and MID1IP1 with ACN increased apoptosis and further reduced the expression of oncogenes. In addition, ACN exhibited a synergistic effect with low-dose 5-fluorouracil (5-FU) and doxorubicin (Dox). Collectively, our data demonstrate that ACN inhibited c-Myc expression through CNOT2 and MID1IP1, and induced apoptosis. These findings indicate the potential of ACN as a therapeutic agent against colon cancer.

RNA-binding motif protein 10 inactivates c-Myc by partnering with ribosomal proteins uL18 and uL5.

RNA-binding motif protein 10 (RBM10) is a frequently mutated tumor suppressor in lung adenocarcinoma (LUAD). Yet, it remains unknown whether cancer-derived mutant RBM10 compromises its tumor suppression function and, if so, the molecular insight of the underlying mechanisms. Here, we show that wild-type RBM10 suppresses lung cancer cell growth and proliferation by inactivating c-Myc that is essential for cancer cell survival. RBM10 directly binds to c-Myc and promotes c-Myc's ubiquitin-dependent degradation, while RBM10 knockdown leads to the induction of c-Myc level and activity. This negative action on c-Myc is further boosted by ribosomal proteins (RPs) uL18 (RPL5) and uL5 (RPL11) via their direct binding to RBM10. Cancer-derived mutant RBM10-I316F fails to bind to uL18 and uL5 and to inactivate c-Myc, thus incapable of suppressing tumorigenesis. Our findings uncover RBM10 as a pivotal c-Myc repressor by cooperating with uL18 and uL5 in lung cancer cells, as its failure to do so upon mutation favors tumorigenesis.

Momordicae Semen inhibits migration and induces apoptotic cell death by regulating c-Myc and CNOT2 in human pancreatic cancer cells.

Pancreatic cancer(PC) is less common than other cancers; however, it has a poor prognosis. Therefore, studying novel target signaling and anticancer agents is necessary. Momordicae Semen (MS), the seed of Momordica sochinensis Spreng, mainly found in South-East Asia, including China and Bangladesh, is used to treat various diseases because of its anticancer, antioxidant, anti-inflammatory, and antibacterial properties. However, the effect of the MS extract on pancreatic cancer cells remains unknown. In this study investigated whether the MS extract exerted an anti-cancer effect by regulating c-Myc through CNOT2. Cytotoxicity and proliferation were investigated using MTT and colony formation assays. The levels of apoptotic, oncogenic, and migration-associated factors were confirmed using immunoblotting and immunofluorescence. Wound closure was analyzed using a wound healing assay. The chemical composition of the MS methanol extracts was analyzed using liquid chromatography-mass spectrometry. We confirmed that the MS extract regulated apoptotic factors and attenuated the stability of c-Myc and its sensitivity to fetal bovine serum. Furthermore, the MS extract increased apoptosis by regulating c-Myc and CNOT2 expression and enhanced the sensitivity of 5-FU in pancreatic cancer. This study showed that the MS extract is a promising new drug for PC.

Viscum album Induces Apoptosis by Regulating STAT3 Signaling Pathway in Breast Cancer Cells.

In this study, we investigated the potential anticancer effects of Viscum album, a parasitic plant that grows on Malus domestica (VaM) on breast cancer cells, and explored the underlying mechanisms. VaM significantly inhibited cell viability and proliferation and induced apoptosis in a dose-dependent manner. VaM also regulated cell cycle progression and effectively inhibited activation of the STAT3 signaling pathway through SHP-1. Combining VaM with low-dose doxorubicin produced a synergistic effect, highlighting its potential as a promising therapeutic. In vivo, VaM administration inhibited tumor growth and modulated key molecular markers associated with breast cancer progression. Overall, our findings provide strong evidence for the therapeutic potential of VaM in breast cancer treatment and support further studies exploring clinical applications.

Euonymus sachalinensis Induces Apoptosis by Inhibiting the Expression of c-Myc in Colon Cancer Cells.

We hypothesized that Euonymus sachalinensis (ES) induces apoptosis by inhibiting the expression of c-Myc in colon cancer cells, and this study proved that the methanol extract of ES has anticancer effects in colon cancer cells. ES belongs to the Celastraceae family and is well known for its medicinal properties. Extracts of species belonging to this family have been used to treat diverse diseases, including rheumatoid arthritis, chronic nephritis, allergic conjunctivitis, rhinitis, and asthma. However, ES has been targeted because there are currently few studies on the efficacy of ES for various diseases, including cancer. ES lowers cell viability in colon cancer cells and reduces the expression of c-Myc protein. We confirm that the protein level of apoptotic factors such as PARP and Caspase 3 decrease when ES is treated with Western blot, and confirm that DNA fragments occur through TUNEL assay. In addition, it is confirmed that the protein level of oncogenes CNOT2 and MID1IP1 decrease when ES is treated. We have also found that ES enhances the chemo-sensitivity of 5-FU in 5-FU-resistant cells. Therefore, we confirm that ES has anticancer effects by inducing apoptotic cell death and regulating the oncogenes CNOT2 and MID1IP1, suggesting its potential for use in the treatment of colon cancer.

Helixor-M Suppresses Immunostimulatory Activity through TLR4-Dependent NF-κB Pathway in RAW 264.7 Cells.

Inflammation causes a protective immune response, which can be observed by examining the inflammatory responses of macrophages. Macrophages release various immunostimulatory factors when destroying external pathogens. We induced lipopolysaccharides (LPS) in RAW 264.7 cells, a macrophage cell line, to determine whether Helixor-M can cause immuno-suppression. Helixor-M is known to have anticancer and immune effects. However, an indicator that regulates immunity has not been clearly confirmed. To this end, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was conducted to confirm Helixor-M was not cytotoxic. Western blotting and real-time polymerase chain reaction (RT-PCR) confirmed the anti-inflammatory effects. Additionally, immunofluorescence assay confirmed the translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65, a representative inflammatory pathway. Helixor-M was found to be non-cytotoxic, induce the NF-κB pathway, and reduce the levels of pro-inflammatory cytokine and mitogen-activated protein kinase (MAPK). We found Helixor-M affected the PI3K/AKT/JNK pathway. Therefore, we confirmed Helixor-M acts as an anti-inflammatory agent through NF-κB, TLR4 and PI3K inhibition and that it could be an effective immunosuppressive drug.

Coiled-coil domain containing 3 suppresses breast cancer growth by protecting p53 from proteasome-mediated degradation.

Coiled-coil domain containing 3 (CCDC3) was previously shown to regulate liver lipid metabolism as a secretory protein. Here, we report an unexpected intracellular role of CCDC3 as a tumor suppressor in breast cancer (BrC). Bioinformatics datasets analysis showed that CCDC3 is under-expressed in BrCs, while its higher levels are correlated with higher overall survival and lower relapse of cancer patients, and CCDC3 is positively correlated with p53 and its target genes. Ectopic CCDC3 markedly suppressed proliferation, colony formation, and xenograft tumor growth by augmenting p53 activity in BrC cells. Depletion of endogenous CCDC3 by CRISPR-Cas9 increased proliferation and drug resistance of BrC cells by alleviating 5-Fluorouracil (5-FU)-induced p53 level and activity. Mechanistically, CCDC3 bound to the C-termini of p53 and MDM2, consequently stabilizing p53 in the nucleus and impairing MDM2 recruitment of p53 to the 26S proteosome without inhibiting p53 ubiquitination. p53 induced CCDC3 expression by binding to its promoter in BrC cells. Our results unveil a unique mechanism underlying CCDC3 activation of p53 in a positive feedback fashion to suppress BrC growth.

Ophiopogonin D increase apoptosis by activating p53 via ribosomal protein L5 and L11 and inhibiting the expression of c-Myc via CNOT2.

Ophiopogonin D (OP-D), which is extracted from the root tuber of Ophiopogon japonicus, is well known for its anti-inflammatory, anti-oxidant, and anti-cancer effects. It is also therapeutic for various diseases such as diabetic myocardial injuries, obesity, atopic dermatitis, and osteoporosis. However, there are insufficient reports on the anti-cancer effects and molecular mechanisms of OP-D in colorectal cancer. Therefore, this study aimed to investigate the anti-cancer-modulating effect of OP-D on colorectal cancer. The study proved that OP-D (20-40 uM) has significant cell viability inhibition and anti-proliferative effects in Cell Counting Kit-8 (CCK-8) assay and colony formation assay. In addition, our immunofluorescence analysis data showed that OP-D (40 uM) inhibited the expression of Ki67, a cell proliferation marker, and confirmed that OP-D could induce nucleolar stress by depletion of IPO7 and XPO1. Furthermore, our western blot data showed that OP-D induced p53 expression via ribosomal protein (RP) L5 or L11 and inhibited c-Myc expression through CNOT2 in a dose-dependent manner. Additionally, OP-D regulated cyclin D1 and CDK4, which are well known as cell cycle regulatory proteins. OP-D consistently inhibited the phosphorylation of AKT expression in a dose-dependent manner. Furthermore, OP-D shortened c-Myc's half-life in a time-dependent manner. Furthermore, CNOT2 knockdown enhanced the inhibitory effect of OP-D on c-Myc in colon cancer cells. Besides that, we confirmed that OP-D has a combinational anti-cancer effect of 5-FU or doxorubicin to reduce cell viability and induce apoptosis through p53 and c-Myc regulation. Altogether, our results suggest that OP-D regulates colon cancer cell proliferation and induces apoptosis by inhibiting c-Myc expression via activation of p53 and CNOT2 regulation. The study demonstrated that OP-D may be a promising natural anti-cancer agent for the treatment of colorectal cancer.

Antitumor Effect of Cycloastragenol in Colon Cancer Cells via p53 Activation.

Colorectal cancer cell (CRC) is the fourth most common cancer in the world. There are several chemotherapy drugs available for its treatment, though they have side effects. Cycloastragenol (CY) is a compound from Astragalus membranaceus (Fisch.) Bge known to be effective in aging, anti-inflammatory, anticancer, and anti-heart failure treatments. Although many studies have demonstrated the functions of CY in cancer cells, no studies have shown the effects of p53 in colon cancer cells. In this study, we found that CY reduces the viability of colon cancer cells in p53 wild-type cells compared to p53 null cells and HT29. Furthermore, CY induces apoptosis by p53 activation in a dose- and time-dependent manner. And it was confirmed that it affects the L5 gene related to p53. Additionally, CY enhanced p53 expression compared to when either doxorubicin or 5-FU was used alone. Altogether, our findings suggest that CY induces apoptosis via p53 activation and inhibits the proliferation of colon cancer cells. In addition, apoptosis occurs in colon cancer cells due to other factors. Moreover, CY is expected to have a combined effect when used together with existing treatments for colon cancer in the future.

Natural Products for Esophageal Cancer Therapy: From Traditional Medicine to Modern Drug Discovery.

Esophageal cancer (EC) is one of the most malignant types of cancer worldwide and has a high incidence and mortality rate in Asian countries. When it comes to treating EC, although primary methods such as chemotherapy and surgery exist, the prognosis remains poor. The purpose of this current research is to review the range of effects that natural products have on cancer by analyzing studies conducted on EC. Fifty-seven studies were categorized into four anti-cancer mechanisms, as well as clinical trials. The studies that were scrutinized in this research were all reported within five years. The majority of the substances reviewed induced apoptosis in EC, acting on a variety of mechanisms. Taken together, this study supports the fact that natural products have the potential to act as a candidate for treating EC.

The Antitumor Effect of Timosaponin A3 through c-Myc Inhibition in Colorectal Cancer Cells and Combined Treatment Effect with 5-FU or Doxorubicin.

Timosaponin A3 (TA3), extracted from the rhizome of Anemarrhenaasphodeloides Bunge, has been reported to affect various diseases, such as cancer, Alzheimer's disease, and allergies. However, the underlying molecular mechanisms and impacts are largely unknown. In the present study, we hypothesized that TA3 induces apoptosis through the inhibition of c-Myc expression via CNOT2 or MID1IP1 in HCT116. An MTT assay and colony formation assay were used to measure cell viability and proliferation. The protein expression of apoptotic markers and oncogenes was measured using immunoblotting and immunofluorescence assays. The interaction between MID1IP1 and c-Myc was confirmed by performing an immunoprecipitation assay. TA3 markedly inhibited colon cancer cell proliferation. Consistently, TA3 regulated the apoptotic proteins pro-PARP and caspase 3. TA3 inhibited the half-life of c-Myc and suppressed its expression in response to serum stimulation. In addition, TA3 enhanced the apoptotic effects of doxorubicin and 5-FU in colon cancer cells. Altogether, our results reveal a mechanism by which TA3 induces apoptosis through inhibiting c-Myc expression via CNOT2 or MID1IP1 in HCT116, which may help in the development of new therapies for colon cancer based on TA3 in the future.

Timosaponin A3 Inhibits Palmitate and Stearate through Suppression of SREBP-1 in Pancreatic Cancer.

Timosaponin A3 (TA3) was demonstrated as a potent anticancer chemical by several studies. Although the effects of inhibiting growth, metastasis, and angiogenesis in various cancer cells were demonstrated through multiple mechanisms, the pharmacological mechanism of TA3 shown in pancreatic cancer (PC) is insufficient compared to other cancers. In this study, we aimed to explore the key molecular mechanisms underlying the growth inhibitory effects of TA3 using PC cells and a xenograft model. First, from the microarray results, we found that TA3 regulated INSIG-1 and HMGCR in BxPC-3 cells. Furthermore, we showed that inhibition of sterol regulatory element-binding protein-1 (SREBP-1) by TA3 reduced the fatty acid synthases FASN and ACC, thereby controlling the growth of BxPC-3 cells. We also tried to find mechanisms involved with SREBP-1, such as Akt, Gsk3ß, mTOR, and AMPK, but these were not related to SREBP-1 inhibition by TA3. In the BxPC-3 xenograft model, the TA3 group had more reduced tumor formation and lower toxicity than the gemcitabine group. Interestingly, the level of the fatty acid metabolites palmitate and stearate were significantly reduced in the tumor tissue in the TA3 group. Overall, our study demonstrated that SREBP-1 was a key transcription factor involved in pancreatic cancer growth and it remained a precursor form due to TA3, reducing the adipogenesis and growth in BxPC-3 cells. Our results improve our understanding of novel mechanisms of TA3 for the regulation of lipogenesis and provide a new approach to the prevention and treatment of PC.

Reliability of Alkaline Phosphatase for Differentiating Flare Phenomenon from Disease Progression with Bone Scintigraphy.

The flare phenomenon (FP) on bone scintigraphy after the initiation of systemic treatment seriously complicates evaluations of therapeutic response in patients with bone metastases. The aim of this study was to evaluate whether serum alkaline phosphatase (ALP) can differentiate FP from disease progression on bone scintigraphy in these patients. Breast or prostate cancer patients with bone metastases who newly underwent systemic therapy were reviewed. Pretreatment baseline and follow-up data, including age, pathologic factors, type of systemic therapy, radiologic and bone scintigraphy findings, and ALP levels, were obtained. Univariate and multivariate analyses of these factors were performed to predict FP. An increased extent and/or new lesions were found in 160 patients on follow-up bone scintigraphy after therapy. Among the 160 patients, 80 (50%) had an improvement on subsequent bone scintigraphy (BS), while subsequent scintigraphy also showed an increased uptake in 80 (50%, progression). Multiple regression analysis revealed that stable or decreased ALP was an independent predictor for FP (p < 0.0001). ALP was an independent predictor for FP on subgroup analysis for breast and prostate cancer (p = 0.001 and p = 0.0223, respectively). Results of the study suggest that ALP is a useful serologic marker to differentiate FP from disease progression on bone scintigraphy in patients with bone metastasis. Clinical interpretation for scintigraphic aggravation can be further improved by the ALP data and it may prevent fruitless changes of therapeutic modality by misdiagnosis of disease progression in cases of FP.

UBE2M Drives Hepatocellular Cancer Progression as a p53 Negative Regulator by Binding to MDM2 and Ribosomal Protein L11.

Though UBE2M, an E2 NEDD8-conjugating enzyme, is overexpressed in HepG2, Hep3B, Huh7 and PLC/PRF5 HCCs with poor prognosis by human tissue array and TCGA analysis, its underlying oncogenic mechanism remains unclear. Herein, UBE2M depletion suppressed viability and proliferation and induced cell cycle arrest and apoptosis via cleavages of PARP and caspase 3 and upregulation of p53, Bax and PUMA in HepG2, Huh7 and Hep3B cells. Furthermore, UBE2M depletion activated p53 expression and stability, while the ectopic expression of UBE2M disturbed p53 activation and enhanced degradation of exogenous p53 mediated by MDM2 in HepG2 cells. Interestingly, UBE2M binds to MDM2 or ribosomal protein L11, but not p53 in HepG2 cells, despite crosstalk between p53 and UBE2M. Consistently, the colocalization between UBE2M and MDM2 was observed by immunofluorescence. Notably, L11 was required in p53 activation by UBE2M depletion. Furthermore, UBE2M depletion retarded the growth of HepG2 cells in athymic nude mice along with elevated p53. Overall, these findings suggest that UBE2M promotes cancer progression as a p53 negative regulator by binding to MDM2 and ribosomal protein L11 in HCCs.

Inhibition of CNOT2 Induces Apoptosis via MID1IP1 in Colorectal Cancer Cells by Activating p53.

CCR4-NOT transcription complex subunit 2 (CNOT2), a subunit of the CCR4-NOT complex, has been described in cancer progression. The CNOT complex plays an important role in multiple cellular functions. Recent studies in our laboratory showed that CNOT2 promotes breast cancer cell proliferation and angiogenesis. In addition, CNOT2 signals are critically related to apoptosis induced by atorvastatin in lung cancer cells. Furthermore, depletion of CNOT2 was shown to enhance the antitumor effect of midline 1 interacting protein 1 (MID1IP1) depletion, thus inhibiting c-Myc expression in liver cancer cells. However, the molecular mechanisms related to its oncogenic role remain unclear. Herein, for the first time, we report that CNOT2 inhibition can induce apoptosis in colorectal cancer cells by activating p53. Inhibition of CNOT2 markedly induced apoptosis in various cancer cells like that of the wild-type p53. Furthermore, inhibition of CNOT2 elongated p53 s half-life. Previously, our laboratory demonstrated that MID1IP1 promoted colocalization with c-Myc mediated by CNOT2. Interestingly, inhibition of CNOT2 cannot induce p53 expression without MID1IP1 or apoptosis in cancer cells. In conclusion, our results demonstrate that CNOT2 inhibition induces apoptosis through MID1IP1 by activating p53.

Anti-Obesity Effect of Polygalin C Isolated from Polygala japonica Houtt. via Suppression of the Adipogenic and Lipogenic Factors in 3T3-L1 Adipocytes.

Obesity is a risk factor for metabolic diseases including type 2 diabetes, nonalcoholic steatohepatitis (NASH), heart diseases, and cancer. This study aimed to investigate the anti-obesity effect of Polygalin C (PC) isolated from Polygala japonica Houtt. in 3T3-L1 adipocytes. Based on Oil Red O assay results, PC significantly decreased lipid accumulation compared to the control. We found that PC suppressed adipogenesis transcription factors including peroxisome proliferator-activated receptor γ (PPAR γ) and CCAAT/enhancer-binding protein (C/EBP) α, and lipogenic factors such as sterol regulatory element-binding protein 1c (SREBP 1c) and fatty acid synthase (FAS), in 3T3-L1 adipocytes using Western blotting and real-time polymerase chain reaction (PCR). Moreover, PC inhibited the differentiation of 3T3-L1 cells by regulating the AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) and mitogen-activated protein kinase/protein kinase B (MAPK/Akt) signaling pathways. Additionally, we confirmed that PC inhibited early adipogenesis factors C/EBP ß and C/EBP δ. Therefore, PC inhibited adipogenesis and lipogenesis in vitro. Thus, PC appears to exert potential therapeutic effects on obesity by suppressing lipid metabolism.

Phyotochemical candidates repurposing for cancer therapy and their molecular mechanisms.

Though limited success through chemotherapy, radiotherapy and surgery has been obtained for efficient cancer therapy for modern decades, cancers are still considered high burden to human health worldwide to date. Recently repurposing drugs are attractive with lower cost and shorter time compared to classical drug discovery, just as Metformin from Galega officinalis, originally approved for treating Type 2 diabetes by FDA, is globally valued at millions of US dollars for cancer therapy. As most previous reviews focused on FDA approved drugs and synthetic agents, current review discussed the anticancer potential of phytochemicals originally approved for treatment of cardiovascular diseases, diabetes, infectious diarrhea, depression and malaria with their molecular mechanisms and efficacies and suggested future research perspectives.

Apoptotic and antihepatofibrotic effect of honokiol via activation of GSK3ß and suppression of Wnt/ß-catenin pathway in hepatic stellate cells.

Though honokiol, derived from the Magnolia tree, was known to suppress renal fibrosis, pulmonary fibrosis, non-alcoholic steatoheptitis, inflammation and cancers, the underlying antifibrotic mechanisms of honokiol are not fully understood in hepatic stellate cells until now. Thus, in the present study, inhibitory mechanism of honokiol on liver fibrosis was elucidated mainly in hepatic stellate cells (HSCs) by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell cycle analysis and western-blotting. Honokiol exerted cytotoxicity in LX-2, HSC-T6 and Hep-G2 cells. Honokiol increased sub G1 population and activated caspase 3 and cleaved poly (ADP-ribose) polymerase (PARP) in HSCs. Moreover, honokiol attenuated the expression of alpha smooth muscle actin (α-SMA), transforming growth factor beta 1 (TGF-ß1), phospho-Smad3, phospho-AKT, cyclin D1, c-Myc, Wnt3a, ß-catenin, and activated phosphorylation of glycogen synthase kinase 3 beta (GSK3ß) in HSCs. Conversely, GSK3ß inhibitor SB216763 reversed the effect of honokiol on PARP, α-SMA, phospho-GSK3ß, ß-catenin and sub G1 population in LX-2 cells. Overall, honokiol exerts apoptotic and antifibrotic effects via activation of GSK3ß and inhibition of Wnt3a/ß-catenin signalling pathway.

MicroRNA216b mediated downregulation of HSP27/STAT3/AKT signaling is critically involved in lambertianic acid induced apoptosis in human cervical cancers.

Since heat shock protein (HSP27) is a prognostic marker in cervical cancer, in the present study, the apoptotic mechanism of lambertianic acid (LA) was investigated in human cervical cancers in association with HSP27/STAT3/AKT signaling axis. LA exerted significant cytotoxicity, induced sub-G1 population, and increased the cleavage of Poly (ADP-ribose) polymerase (PARP) and cysteine aspartyl-specific protease 3 (caspase3) in HeLa and Caski cancer cells. Consistently, LA downregulated anti-apopotic genes such as B-cell lymphoma 2 (Bcl-2) and inhibitors of apoptosis proteins (c-IAP) in HeLa and Caski cells. Furthermore, LA-inhibited phosphorylation of HSP27, signal transducer, and activator of transcription 3 (STAT3) and Protein kinase B (AKT) through disturbing the binding of HSP27 with STAT3 or AKT in HeLa cells. Notably, LA upregulated the level of miR216b in HeLa and Caski cells. Consistently, miR216b mimic suppressed phosphorylation of HSP27 and reduced the expression of pro-PARP, while miR216b inhibitor reversed the ability of LA to attenuate phosphorylation of AKT, HSP27, and STAT3 and to reduce the expression of pro-PARP in HeLa cells. Overall, our findings suggest that miRNA216b mediated inhibition of HSP27/STAT3/ AKT signaling axis is critically involved in LA-induced apoptosis in cervical cancers.