HCT116 Human Colorectal Cancer Cells Research Articles

Thermoresponsive and suspension forming cyclotriphosphazene conjugate for delivery vehicle of antitumor drug camptothecin

Camptothecin (CPT) has been used as antitumor drug against a wide range of cancer cells. However, its clinical application is greatly hindered by insolubility and instability issues under physiological condition. Therefore, an appropriate CPT administration technique directed for living system is greatly anticipated. In this study, a delivery method for CPT in the form of thermoresponsive system was prescribed. A conjugate of cyclotriphosphazene and CPT was synthesized by substituting hexachlorocyclotriphosphazene with sodium salt of methoxy-poly (ethylene glycol) (Mw = 350), 20-O-trifluoroglycinylCPT, and isoleucine ethyl ester, respectively. The resulting cyclotriphosphazene-CPT was characterized via multinuclear (1H and 31P) NMR as well as FT-IR. The current conjugate showed temperature induced phase transition (solution to suspension) with a lower critical solution temperature at 31 °C. Our result indicated that the stability issue related to the use of CPT in aqueous solution could be handled by acylation at 20-OH moiety. Additionally, antitumor activity of cyclotriphosphazene-CPT, to some extent, was found to be more profound than that of CPT alone as evaluated against human colorectal cancer cell HCT-116. Altogether, the current cyclotriphosphazene-CPT conjugate might offer a facile method in delivering CPT as a minimally invasive system for treating cancer.

Glucose-6-Phosphate Dehydrogenase Is Not Essential for K-Ras-Driven Tumor Growth or Metastasis.

The enzyme glucose-6-phosphate dehydrogenase (G6PD) is a major contributor to NADPH production and redox homeostasis and its expression is upregulated and correlated with negative patient outcomes in multiple human cancer types. Despite these associations, whether G6PD is essential for tumor initiation, growth, or metastasis remains unclear. Here, we employ modern genetic tools to evaluate the role of G6PD in lung, breast, and colon cancer driven by oncogenic K-Ras. Human HCT116 colorectal cancer cells lacking G6PD exhibited metabolic indicators of oxidative stress, but developed into subcutaneous xenografts with growth comparable with that of wild-type controls. In a genetically engineered mouse model of non-small cell lung cancer driven by K-Ras G12D and p53 deficiency, G6PD knockout did not block formation or proliferation of primary lung tumors. In MDA-MB-231-derived human triple-negative breast cancer cells implanted as orthotopic xenografts, loss of G6PD modestly decreased primary site growth without ablating spontaneous metastasis to the lung and moderately impaired the ability of breast cancer cells to colonize the lung when delivered via tail vein injection. Thus, in the studied K-Ras tumor models, G6PD was not strictly essential for tumorigenesis and at most modestly promoted disease progression. SIGNIFICANCE: K-Ras-driven tumors can grow and metastasize even in the absence of the oxidative pentose pathway, a main NADPH production route.

Potency and Selectivity Optimization of Tryptophanol-Derived Oxazoloisoindolinones: Novel p53 Activators in Human Colorectal Cancer.

To search for novel p53 activators, four series of novel (S)- and (R)-tryptophanol-derived oxazoloisoindolinones were synthesized in a straightforward manner and their antiproliferative activity was evaluated in the human colorectal cancer HCT116 cell line. Structural optimization of the hit compound SLMP53-1 led to the identification of a (R)-tryptophanol-derived isoindolinone that was found to be six-fold more active, with increased selectivity for HCT116 cells with p53 and with low toxicity in normal cells. Binding studies with MDM2 showed that the antiproliferative activity of tryptophanol-derived isoindolinones does not involve inhibition of the main negative regulator of the p53 protein. Molecular docking simulations showed that although these molecules establish hydrophobic interactions with MDM2, they do not possess the required features to bind MDM2.

Quinones from endophytic fungus Fusarium sp. HJT-P-5 of Rhodiola angusta Nakai

Abstract Fourteen quinones were isolated from endophytic fungus Fusarium sp. HJT-P-5 of Rhodiola angusta Nakai. The structures were determined by the chemical and spectroscopic methods. Compounds 1, 8, 9, and 14 are new compounds. The compounds 1, 6, 7, 8, 9, 10, 11, 12, 13 and 14 were evaluated for cytostatic activity against human liver cancer cells HepG2, human lung cancer cells A549, cervical cancer cells Hela, and human colorectal cancer cells HCT116.

Effect of TNIK upregulation on JQ1-resistant human colorectal cancer HCT116 cells

JQ1 disrupts the binding of bromodomain and extra-terminal (BET) family of proteins to acetylated histones, modulates the expression of various genes, and inhibits the proliferation of cancer cells. We established two JQ1-resistant sublines from human colorectal cancer HCT116 cells. These resistant cells showed an 8- to 9-fold higher resistance to JQ1, and a 2- to 4-fold higher resistance to various anti-cancer agents, such as doxorubicin, etoposide, mitoxantrone, SN-38, cisplatin, and methotrexate than the parental HCT116 cells. The JQ1-resistant cells expressed higher levels of TRAF2 and NCK-interacting protein kinase (TNIK), cyclin D1 (CCND1), cyclin E1 (CCNE1), and their corresponding mRNAs than the parental cells. TNIK is a regulator of Wnt/β-catenin signaling and is known to transactivate CCND1. Transient transfection of HCT116 cells with a TNIK expression plasmid resulted in the upregulation of cyclin D1, cyclin E1, and their corresponding mRNAs, as well as an increase in CCNE1 promoter activity. Furthermore, luciferase assay revealed that the JQ1-resistant cells showed high CCNE1 promoter activity. These results suggest that TNIK also transactivates CCNE1. Three stable TNIK transfectant clones of HEK293 cells expressed 1.5- to 2-fold higher levels of TNIK, cyclin D1, and cyclin E1 than the parental cells. The 293/TNIK-6 cells, which expressed the highest level of TNIK among the transfectants, showed a 2.3-fold higher resistance to JQ1 than the parental cells. These results suggest the possible involvement of TNIK in cellular resistance to JQ1.

Luteolin overcomes resistance to benzyl isothiocyanate-induced apoptosis in human colorectal cancer HCT-116 cells

We have previously identified p53, a universal sensor of genotoxic stress, as a negative regulator of the apoptosis induction by benzyl isothiocyanate (BITC) in the normal colon fibroblastoid cells. In the present study, we further confirmed that BITC has a potential to induce cytotoxicity in the p53-mutated colon cancer HT-29 cells in preference to HCT-116 cells with wild-type p53. To obtain effective induction of BITC-stimulated apoptosis in p53-positive cells, we investigated the combination effect of BITC and food ingredient that may overcome resistance to BITC. Pretreatment with luteolin potentiated the cytotoxicity induction by BITC in HCT-116 cells but not in HT-29 cells. The biochemical events related to apoptosis such as DNA ladder formation and caspase-3 activation were also enhanced by luteolin. Luteolin attenuated the expression of p21waf1/cip1, a key downstream target of p53. These results suggest the role of p21waf1/cip1 pathway in the overcoming BITC resistance by luteolin.

Design, synthesis and antitumour evaluation of pyrrolo[1,2-f]-phenanthridine and dibenzo[f,h]pyrrolo[1,2-b]isoquinoline derivatives

A series of 1,2-bis(hydroxymethyl)pyrrolo[1,2-f]phenanthridine derivatives and their alkyl (ethyl and isopropyl) carbamates and 12,13-bis(hydroxymethyl)-9,14-dihydro-dibenzo[f,h]pyrrolo[1,2-b]isoquinoline derivatives were synthesized for antiproliferative evaluation. The preliminary antitumour studies revealed that these two types of bis(hydroxymethyl) derivatives showed significant antitumour activities and were able to inhibit the growth of various human tumour cell lines in vitro. Several of the derivatives were demonstrated to cause DNA interstrand cross-links by an alkaline agarose gel shifting assay. These conjugates were cytotoxic to a variety of cancer cell lines by inducing DNA damage, delaying cell cycle progression in the G2/M phase and triggering apoptosis. Compound 21a, dissolved in a vehicle suitable for intravenous administration, was selected for antitumour studies in animal models. We demonstrated that at a dose that did not cause body weight loss in mice, compound 21a could significantly suppress the growth of tumour xenografts of human lung cancer H460 and colorectal cancer HCT-116 cells in nude mice. Our present results confirm the antitumour activities of these conjugates.

Lignans and Polyphenols of Phyllanthus amarus Schumach and Thonn Induce Apoptosis in HCT116 Human Colon Cancer Cells through Caspases-Dependent Pathway.

The anticancer effects of Phyllanthus amarus extract on various cancer cells have been investigated, however, the effects of its major constituents on HCT116 human colorectal cancer cells have not been reported. In the present study, we investigated the cytotoxic effect of 80% ethanol extract of P. amarus and its marker constituents (phyllanthin, hypophyllanthin, gallic acid, niranthin, greraniin, phyltetralin, isolintetralin, corilagin and ellagic acid) on HCT116 and their underlying mechanisms of action. Their antiproliferative and apoptotic effects on HCT 116 were performed using MTT assay and flow cytometric analysis, respectively, while caspases 3/7, 8 and 9 activities were examined using the colorimetric method. The expression of cleaved poly ADP ribose polymerase enzyme (PARP) and cytochrome c proteins was investigated by the immune-blot technique. HPLC and LC-MS/MS analyses demonstrated that the extract contained mainly lignans and polyphenols. The plant samples markedly suppressed the growth and expansion of HCT116 cells in a concentration- and time-dependent manner with no toxicity against normal human fibroblast CCD18 Co. P. amarus extract, phyllanthin and gallic acid induced mode of cell death primarily through apoptosis as confirmed by the exteriorization of phosphatidylserine. Caspases 3/7, 8, and 9 activities increased in a concentration-dependent manner following 24h treatment. The expressions of cleaved PARP (Asp 214) and cytochrome c were markedly upregulated. P. amarus extract, phyllanthin and gallic acid exhibited an apoptotic effect on HCT116 cells through the caspases-dependent pathway.

Nrf2‐Activating Phytochemicals, Sulforaphane and Licochalcone A, Stimulate Cell Growth‐Regulating Kinases in HCT116 Human Colorectal Cancer Cells

Some phytochemicals have been reported to modulate phase II detoxifying/antioxidant enzyme expressions via both Keap1 (Kelch‐like ECH‐associated protein 1)‐dependent and independent regulations of a nuclear factor E2‐related factor 2/antioxidant response element (Nrf2/ARE) system. Based on multiple studies, various kinase signaling pathways are also responsible for regulation of Nrf2/ARE activity differently depending on cell types, microenvironmental factors, treatment doses, etc. Sulforaphane (SFN) and licochalcone A (LicA) are known as potent Nrf2/ARE inducers that can modulate several kinases including phosphoinositide 3‐kinase (PI3K)/Protein kinase B (Akt) and p38 mitogen‐activated protein kinase (MAPK) in propagating cancer cells. The purpose of the present study was to investigate the molecular mechanism through which SFN and LicA can activate Nrf2/ARE system and upregulate heme oxygenase‐1 (HO‐1) expression in HCT116 human colorectal cancer cells. Results revealed that SFN and LicA induced ARE‐transcriptional activity and subsequently increased HO‐1 expression through PI3K and p38 MAPK signaling pathways in HCT116 cells. In addition, HCT116 cell proliferation was significantly promoted when Nrf2/ARE activity was increased by either SFN‐induced PI3K activation or LicA‐induced p38 MAPK activation. These observations indicate that SFN and LicA regulated the Nrf2/ARE/HO‐1 system via phosphorylation of PI3K and p38 MAPK, respectively, in proliferation of HCT116 colorectal cancer cells. In conclusion, the present study highlights the working mechanism of potent Nrf2/ARE activators that possibly perturb the activities of various kinases in the growing cancer cells.Support or Funding InformationThis work was supported by the National Research Foundation of Korea grant (Grant No. 2017R1A2B4005087) funded by the Ministry of Science and ICT, Republic of Korea.

Analysis and Identification of Active Compounds from Salviae miltiorrhizae Radix Toxic to HCT-116 Human Colon Cancer Cells

Colorectal cancer is one of the most frequently diagnosed cancers worldwide. The aim of the present study was to simultaneously analyze compounds of Salviae miltiorrhizae Radix (SMR) and determine their cytotoxic effects on HCT-116 human colorectal cancer cells. We established a simultaneous analysis method of five compounds (salvianic acid A, salvianolic acid B, caffeic acid, tanshinone IIA, and rosmarinic acid) contained in SMR, and found that among the various compounds in SMR, tanshinone IIA significantly decreased cell viability in a concentration-dependent manner. Hoechst staining also showed that both SMR and tanshinone IIA increased nuclear condensation, suggesting induction of apoptosis. By Western blotting, we found that tanshinone IIA induced apoptotic cell death, significantly increased Bax, but decreased Bcl-2 in the course of apoptosis. Tanshinone IIA increased the expression of cleaved caspases-7 and -8. Tanshinone IIA was shown to be an active ingredient of SMR that may be a useful chemotherapeutic strategy for patients with colorectal cancer.

Oligo-Fucoidan Prevents M2 Macrophage Differentiation and HCT116 Tumor Progression

Reactive oxygen species (ROS) produced during intracellular metabolism or triggered by extrinsic factors can promote neoplastic transformation and malignant microenvironment that mediate tumor development. Oligo-Fucoidan is a sulfated polysaccharide isolated from the brown seaweed. Using human THP-1 monocytes and murine Raw264.7 macrophages as well as human HCT116 colorectal cancer cells, primary C6P2-L1 colorectal cancer cells and human MDA-MB231 breast cancer cells, we investigated the effect of Oligo-Fucoidan on inhibiting M2 macrophage differentiation and its therapeutic potential as a supplement in chemotherapy and tumor prevention. We now demonstrate that Oligo-Fucoidan is an antioxidant that suppresses intracellular ROS and mitochondrial superoxide levels in monocytes/macrophages and in aggressive cancer cells. Comparable to ROS inhibitors (DPI and NAC), Oligo-Fucoidan directly induced monocyte polarization toward M1-like macrophages and repolarized M2 macrophages into M1 phenotypes. DPI and Oligo-Fucoidan also cooperatively prevented M2 macrophage invasiveness. Indirectly, M1 polarity was advanced particularly when DPI suppressed ROS generation and supplemented with Oligo-Fucoidan in the cancer cells. Moreover, cisplatin chemoagent polarized monocytes and M0 macrophages toward M2-like phenotypes and Oligo-Fucoidan supplementation reduced these side effects. Furthermore, Oligo-Fucoidan promoted cytotoxicity of cisplatin and antagonized cisplatin effect on cancer cells to prevent M2 macrophage differentiation. More importantly, Oligo-Fucoidan inhibited tumor progression and M2 macrophage infiltration in tumor microenvironment, thus increasing of anti-tumor immunity.

Antitumor activity of nervosine VII, and the crosstalk between apoptosis and autophagy in HCT116 human colorectal cancer cells

Nervosine VII is one of the known saturated pyrrolizidine alkaloids isolated from the plant of Liparis nervosa. This is first study to investigate the antitumor activity of nervosine VII in vitro, and the results indicated that nervosine VII induced autophagy and apoptosis in HCT116 human colorectal cancer cells. Mechanistic studies showed that nervosine VII-induced apoptosis was associated with the intrinsic pathway by the activation of caspase-9, -3 and -7. Autophagy induced by nervosine VII was characteristic with the regulation of autophagic markers including the increase of LC3-II and beclin 1 proteins, and the decrease of p62 protein. Nervosine VII simultaneously induced autophagy and apoptosis by activated MAPKs signaling pathway including JNK, ERK1/2 and p38, suppressing the p53 signaling pathway.

Antitumor Activity of Ohmyungsamycin A through the Regulation of the Skp2-p27 Axis and MCM4 in Human Colorectal Cancer Cells.

Ohmyungsamycin A (1), a novel cyclic peptide discovered from a marine Streptomyces sp., was previously reported with antibacterial and anticancer activities. However, the antitumor activities and the underlying molecular mechanisms of 1 remain to be elucidated. Compound 1 inhibited the proliferation and tumor growth of HCT116 human colorectal cancer cells based on both in vitro cell cultures and an in vivo animal model. A cDNA microarray analysis revealed that 1 downregulated genes involved in cell cycle checkpoint control. Compound 1 also induced G0/G1 cell cycle arrest that was mediated by the regulation of S-phase kinase-associated protein 2 (Skp2)-p27 axis and minichromosome maintenance protein 4 (MCM4). Furthermore, a longer exposure of 1 exhibited an accumulation of a sub-G1 phase cell population, which is characteristic of apoptotic cells. The induction of apoptosis by 1 was also associated with the modulation of caspase family proteins. Compound 1 effectively suppressed tumor growth in a xenograft mouse model subcutaneously implanted with HCT116 cells. In addition, analysis of tumors revealed that 1 upregulated the expression of the CDK inhibitor p27 but downregulated the expression of Skp2 and MCM4. These findings demonstrate the involvement of 1 in cell cycle regulation and the induction of apoptosis in human colorectal cancer cells.

Crocetin suppresses the growth and migration in HCT-116 human colorectal cancer cells by activating the p-38 MAPK signaling pathway.

Background and purpose:Crocetin is a natural antioxidant that is found in the crocus flower and Gardenia jasminoides (fruit). Previous studies have reported its anticancer activity both in vivo and in vitro. In addition, crocetin suppresses the growth and migration of human colorectal cancer cells, however, its mechanism of action remains to be elucidated. Therefore, the present study investigated the molecular mechanism of crocetin effect on colorectal cancer cells (HCT-116) in vitro.Experimental approach:HCT-116 cells were treated with different concentrations (0, 200, 400, 600, and 800 μM) of crocetin for 24 h. The cell survival rate was measured by MTT assay. Cell migration capacity was evaluated using the wound healing assay. The expression levels of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP-9) was monitored by RT-PCR. Phosphorylation of focal adhesion kinase (FAK) and p38 mitogen-activated protein kinase (MAPK) was determined using western blot.Findings/Results:The proliferation of HCT-116 was inhibited by crocetin at 800 μM (P < 0.001). Crocetin prevented migration of HCT-116 cells (P < 0.05) and suppressed VEGF and MMP-9 mRNA expression (P < 0.001) and increased phosphorylation of p38 (MAPK; P < 0.001). However, no significant change in the phosphorylation of FAK was observed.Conclusion and implication:These data suggested that crocetin-induced growth- and migration- suppressing effects on HCT-116 cells may partially depend on the regulation of the p38 (MAPK) signaling pathway.

Deoxyelephantopin induces ROS-mediated autophagy and apoptosis in human colorectal cancer in vitro and in vivo

Objective: To systematically map the stepwise events leading to deoxyelephantopin-induced cell death of HCT116 human colorectal cancer cells and evaluate the effectiveness of deoxyelephantopin in vivo.Methods: HCT116 cells were treated with deoxyelephantopin at various concentrations and time points. Autophagy was confirmed by the detection of autophagosomes and autophagosomal proteins by electron microscopy and Western blotting assays, respectively, and then validated by siRNA knockdown. In addition, apoptosis was confirmed by the detection of apoptosis-related proteins. The intracellular reactive oxygen species (ROS) level was measured using flow cytometry. The growth inhibitory effect of deoxyelephantopin was further evaluated in vivo using a mouse xenograft model.Results: Deoxyelephantopin firstly elevated ROS production, which then triggered autophagic flux with the accumulation of autophagosomal proteins including LC3A/B, ATG5, and ATG7, followed by the induction of apoptosis via the intrinsic and extrinsic pathways. Pre-treatment with N-acetyl-L-cysteine, a ROS inhibitor, reversed both apoptosis and autophagy. The knockdown of LC3 prevented apoptosis induction which confirmed that deoxyelephantopin induced autophagy-dependent apoptosis in HCT116 cells. Accumulation of ROS also activated apoptosis via the mitogen-activated protein kinases signaling pathway. Furthermore, deoxyelephantopin also inhibited the PI3K/AKT/mTOR pathway, which then released the inhibition of autophagy. In vivo study further showed that deoxyelephantopin significantly suppressed the growth of HCT116 subcutaneous xenograft in nude mice.Conclusions: Our findings revealed that deoxyelephantopin elevates oxidative stress and induces ROS-dependent autophagy followed by apoptosis in HCT116 cells via the concerted modulation of multiple signaling pathways. These findings further support the development of deoxyelephantopin as a therapeutic agent for colorectal cancer.

Bardoxolone Methyl (CDDO-Me or RTA402) Induces Paraptosis Through Reactive Oxygen Species-mediated Endoplasmic Stress and Intracellular Calcium Release in Human Colorectal Cancer HCT-116 Cells

Bardoxolone Methyl (CDDO-Me or RTA402) Induces Paraptosis Through Reactive Oxygen Species-mediated Endoplasmic Stress and Intracellular Calcium Release in Human Colorectal Cancer HCT-116 Cells

SNAIL- and SLUG-induced side population phenotype of HCT116 human colorectal cancer cells and its regulation by BET inhibitors

Epithelial-mesenchymal transition (EMT) is associated with cancer malignancies such as invasion, metastasis, and drug resistance. In this study, HCT116 human colorectal cancer cells were transduced with SLUG or SNAIL retroviruses, and EMT cells with mesenchymal morphology were established. The EMT cells showed a high invasive activity and resistance to several anticancer agents such as methotrexate, SN-38, and cisplatin. Furthermore, they contained about 1–10% side population (SP) cells that were not stained by Hoechst 33342. This SP phenotype was not stable; the isolated SP cells generated both SP and non-SP cells, suggesting a potential for differentiation. Gene expression analysis of SP cells suggested the alteration of genes that are involved in epigenetic changes. Therefore, we examined the effect of 74 epigenetic inhibitors, and found that two inhibitors, namely I-BET151 and bromosporine, targeting the bromodomain and extra-terminal motif (BET) proteins, decreased the ratio of SP cells to <50% compared with the control, without affecting the immediate efflux of Hoechst 33342 by transporters. In addition, compared with the parental cells, the EMT cells showed a higher sensitivity to I-BET151 and bromosporine. This study suggests that EMT development and SP phenotype can be independent events but both are regulated by BET inhibitors in SLUG- or SNAIL-transducted HCT116 cells.

65P - Novel HDACi, MHY446, induces apoptosis via regulation of mitochondria-endoplasmic reticulum interaction in HCT116 human colorectal cancer cells

BackgroundColorectal cancer (CRC) is one of the leading causes of cancer-related death in the world. Despite considerable research and advancement in CRC diagnosis and therapy, CRC is still clinically challenging and becoming the highest incidence cancer worldwide. There is a need to develop novel therapeutic agents for this malignancy. MethodsMHY446, a novel histone deacetylase inhibitor (HDACi), was synthesized on the backbone of hydroxamic acid derivatives that are one of the HDAC inhibitors. We evaluated cytotoxic effects and underlying molecular mechanisms of actions of MHY446 in HCT116 human colorectal cancer cells. ResultsMHY446-treated HCT116 cells exhibited cell viability inhibition and an increase in the sub-G1 phase populations and late apoptosis. MHY446-induced apoptosis is accompanied by the activation of caspase-8, -9, and -3; subsequent cleavage of poly(ADP-ribose) polymerase; and alteration in the ratio of Bax/Bcl-2 protein expression level. The presence of Z-VAD-FMK, a pan-caspase inhibitor, significantly attenuated the MHY446-induced apoptosis indicating that apoptotic cell death was caspase-dependent cascading through the activation of both intrinsic and extrinsic signaling pathways. Furthermore, MHY446 caused the loss of mitochondria membrane potential and induced the generation of reactive oxygen species (ROS), evidenced by the scavenging of ROS by N-acetyl-L-cysteine (NAC). Additionally, MHY446 promoted the upregulation of the expression level of endoplasmic reticulum (ER) stress-associated proteins such as BIP, PDI, IRE1α, PERK, p-elF2α, and CHOP. NAC effectively reduced the expression of ER stress-related protein levels, suggesting that ROS acts as an upstream signaling molecule in triggering the ER stress pathway. ConclusionsTaken together, these results demonstrate that MHY446 exerts its anticancer activities through the regulation of ROS-induced ER stress. These results suggest that MHY446 is a promising candidate for the treatment of CRC. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Extract from Aloysia polystachya Induces the Cell Death of Colorectal Cancer Stem Cells

Cancer stem cells (CSCs) are an important player in the resistance of cancers to therapy. In this work, we determined the flavonoids composition and biological action of Aloysia polystachya (AP) extracts in colorectal cancer. The chemical characterization of extracts was performed by HPLC. Assays of cytotoxicity, apoptosis, migration and invasion, metalloproteases activity, clonogenic growth, tumorspheres formation, Hoechts efflux, pluripotency marker expression and sensitization to chemotherapeutic drugs were performed in vitro in human HCT116 and murine CT26 colorectal cancer cells. The AP toxicity and effect in tumor growth administered alone or in combination with 5- Fluorouracile was analyzed in vivo, including histopathological studies. We found that AP extracts induced in vitro the apoptosis of colorectal cancer cell lines decreasing the CSC proportion. Moreover, they were capable to kill 5-Fluorouracile resistant side population cells. At not toxic doses in vivo, AP extracts inhibited tumor growth. Regarding the ability to reduce the CSC population, AP extracts deserves to be investigated as a useful therapy for colorectal cancer treatment.

SNX3 suppresses the migration and invasion of colorectal cancer cells by reversing epithelial-to-mesenchymal transition via the β-catenin pathway.

The Wnt/β-catenin signaling pathway is a well-studied pathway that drives the carcinogenesis and metastasis of colorectal cancer (CRC). The secretion of Wnt proteins is essential for the continuous activation of Wnt/β-catenin signaling in CRC. The secretion of Drosophila wingless, which is homologous to the human Wnt protein, is mediated by sorting nexin 3 (SNX3) in Drosophila; however, the role of SNX3 in CRC remains unknown. In the present study it was demonstrated that SNX3 reduced the migratory and invasive ability of HCT116 human CRC cells, and reversed epithelial-mesenchymal transition (EMT). Conversely, in the HT29 CRC cell line, which endogenously expresses high levels of SNX3, short hairpin RNA or siRNA-mediated knockdown of SNX3 induced EMT, and enhanced cell migration and invasion. In addition, upregulation of SNX3 significantly inhibited metastasis of HCT116 cells to the lungs of mice. These SNX3-mediated effects were associated with downregulation of β-catenin. Taken together, by downregulating β-catenin, SNX3 may mediate EMT and reverse CRC metastasis.