Efficacy of butyrate analogues in HT‐29 cancer cells

1. Butyrate is a well known product of starch fermentation by colonic bacteria and is of interest owing to its ability to induce in vitro apoptosis and cell differentiation, as well as to inhibit cell growth in colorectal and other cancer cells. Synthetic analogues of butyrate may also possess cellular activities in a variety of cultured cells. The aim of the present study was to evaluate the effects of butyrate analogues on apoptosis, proliferation and histone deacetylase (HDAC) activity in HT‐29 colorectal cancer cells. In addition, the effects of these analogues on lactate dehydrogenase leakage, as a measure of non‐specific cytotoxicity, were evaluated in HT‐29 cells. 2. Of the 26 analogues examined, four (propionate, 4‐benzoylbutyrate, 4‐(4‐aminophenyl)butyrate and benzyloxyacetate) exhibited comparable effects to butyrate. Interestingly, no activity was noted for compounds carrying amino, hydroxyl or methyl substitutions at the 2‐, 3‐ or 4‐position of the aliphatic moiety of butyrate. 3. In conclusion, chemical changes to the structure of butyrate can significantly modify the biological activity assayed in HT‐29 colorectal cancer cells in vitro.     

TIP30基因启动子甲基化与大肠癌细胞奥沙利铂化疗敏感性关系的研究

目的探讨TIP30启动子CpG岛甲基化状态与大肠癌细胞对奥沙利铂敏感性的关系。方法采用MTT法检测HCT116和HT29大肠癌细胞株对L-OHP的敏感性。通过甲基化特异性PCR,检测对奥沙利铂敏感性有差异的2个大肠癌细胞株中TIP30基因启动子CpG岛甲基化状态,并用RT-PCR法检测其mRNA表达。结果 HCT116及HT29细胞中TIP30基因甲基化状态存在差异,其表达水平与启动子CpG岛甲基化状态有关,并且二者对奥沙利铂的敏感性不同。结论 TIP30基因启动子甲基化状态可能影响大肠癌细胞对化疗药物的敏感性,为大肠癌患者的个体化治疗提供了依据。     

西红花苷抑制NFATc3活性促进与肿瘤成纤维细胞共培养的结直肠癌细胞放射敏感性

目的 探究西红花苷对与肿瘤成纤维细胞（CAFs）共培养的结直肠癌细胞放射敏感性的影响,并探究分子机制。方法 通过实时荧光定量聚合酶链式反应（qRT-PCR）和蛋白质免疫印记（Western blotting）比较人正常结肠上皮细胞NCM460和结直肠癌细胞系SW480、SW620、HCT116、LOVO中活化T细胞核因子c3（NFATc3）表达差异。建立CAFs与HCT116细胞共培养体系,西红花苷处理细胞后经不同剂量（0、2、4、6、8 Gy）X射线照射,细胞克隆形成实验分析细胞存活分数（SF）。再将HCT116细胞分为对照组、6 Gy组、CAFs/HCT116＋6 Gy组、CAFs/HCT116＋西红花苷＋6 Gy组,进行对应处理后,MTT法检测各处理组HCT116细胞活性,流式细胞术检测各处理组HCT116细胞凋亡率,Hoechst 33258染色观察各处理组HCT116细胞凋亡形态,qRT-PCR和Western blotting测定各处理组HCT116细胞中NFATc3表达水平。结果 相较于人正常结肠上皮细胞NCM460,人结直肠癌细胞系SW480、SW620、HCT116、LOVO中的NFATc3 mRNA和蛋白相对表达量均显著上调（P＜0.05）。与HCT116细胞比较,与CAFs共培养的HCT116细胞经辐射后的SF显著增高（P＜0.05）;与CAFs共培养的HCT116细胞比较,与CAFs共培养的HCT116细胞经西红花苷处理再进行辐射的SF显著降低（P＜0.05）。与6 Gy组比较,CAFs/HCT116＋6 Gy组HCT116细胞存活率显著升高（P＜0.05）,细胞凋亡率显著下降（P＜0.05）,细胞内染色也较为均匀,未见致密浓染的凋亡状细胞,细胞中NFATc3 mRNA和蛋白相对表达量均显著上调（P＜0.05）;而与CAFs/HCT116＋6 Gy组比较,CAFs/HCT116＋西红花苷＋6 Gy组HCT116细胞存活率显著降低（P＜0.05）,细胞凋亡率显著升高（P＜0.05）,细胞中有较多致密浓染、碎裂荧光块,同时,细胞中NFATc3 mRNA和蛋白相对表达量显著下调（P＜0.05）。结论 西红花苷能够明显提高与CAFs共培养的结直肠癌HCT116细胞的放射敏感性,从而促进细胞发生凋亡,该作用可能与抑制NFATc3有关。     

Antilipase and antiproliferative activities of novel fluoroquinolones and triazolofluoroquinolones

Fluoroquinolones (FQs) have been identified recently as potent inhibitors of pancreatic lipase (PL). The aim of this study was to synthesize novel FQs and triazolofluoroquinolones (TFQs) and to evaluate them in vitro with respect to their antilipolytic efficacy and potency properties. The PL‐IC₅₀ values of 12 FQs and TFQs ( 3 ( a–c ) –6 ( a–c )) were in the range of 12.5–189.1 μm . These values are further supported by docking studies. The suggested association between obesity and colorectal cancer initiated the evaluation of antiproliferative activity of the new FQs and TFQs against a panel of obesity‐related colorectal cells (HT29, HCT116, SW620 CACO2, and SW480). Sulforodamine B colorimetric assay revealed that some derivatives exhibited unselective cytotoxicity against HT29, HCT116, SW620 CACO2, and SW480. Remarkably, FQ 4a 's selective cytotoxicity against HCT116 was found valuable with IC₅₀ value of 4.2 μm which exceeds that of cisplatin with a substantial selective cytotoxicity in periodontal ligament fibroblasts. In conclusion, FQ and TFQ derivatives may unveil new antiobesity and anticancer agents in the future.     

Rational drug design of indazole‐based diarylurea derivatives as anticancer agents

A series of novel indazole‐based diarylurea derivatives targeting c‐kit were designed by structure‐based drug design. The derivatives were prepared, and their antiproliferative activities were evaluated against human colon cancer HCT‐116 cell line and hepatocellular carcinoma PLC/PRF/5 cell line. The antiproliferative activities demonstrated that six of nine compounds exhibited comparable activities with sorafenib against HCT‐116. The structure–activity relationship (SAR) analysis indicated that the indazole ring part tolerated different kinds of substituents, and the N position of the central pyridine ring played key roles in antiproliferative activity. The SAR and interaction mechanisms were further explored using molecular docking method. Compound 1i with N‐(2‐(pyrrolidin‐1‐yl)ethyl)‐carboxamide possessed improved solubility, 596.1 ng/ml and best activities, IC₅₀ at 1.0 μm against HCT‐116, and 3.48 μm against PLC/PRF/5. It is a promising anticancer agent for further development.     

Synthesis of New Congeners of 1‐methyl‐3‐aminoisoquinolines,Evaluation of Their Cytotoxic Activity,In Silico and In Vitro Study of Their Molecular Targets as PDE4B

To examine the cytotoxic activity of congeners of 3‐amino‐isoquinoline, we performed the phenotypic screening using panel of 60 cell lines and found that (N‐(6,7‐dimethoxy‐1‐methyl‐isoquinolin‐3‐yl)‐4‐{[(1‐ethyl‐4‐methyl‐1H‐pyrazol‐3‐yl)methyl]amino}benzamide ( 4d )) exhibited the significant effect against different tumor cell lines while showing the high activity toward human colorectal cancer HCT‐116 cells (IC₅₀ = 18 μm ) and human breast cancer T‐47D cells (GI₅₀ = 1.9 μm ). Virtual screening indicated that these compounds target protein kinases and phosphodiesterases (PDE). However, wet screening among panel of protein kinases did not show any significant activity. By contrast, 50 μm of 4c and 4d inhibited the growth of HKe3‐mtKRAS spheroids in the 3D floating (3DF) culture suggesting that 4c and 4d target PDE4B which is selectively upregulated by mtKRAS in 3DF culture.     

Synthesis, structure, anticancer, and antioxidant activity of para-xylyl linked bis-benzimidazolium salts and respective dinuclear Ag(I) N-heterocyclic carbene complexes (Part-II)

The article describes synthesis, characterization (NMR, FT-IR, microanalysis, X-ray crystallography), in vitro anticancer, and antioxidant activity of para-xylyl linked bis-benzimidazolium salts and respective dinuclear Ag–NHC complexes. All the compounds were tested for their cytotoxicity against human colorectal cancer cells (HCT 116) and DPPH antioxidant evaluation. According to cell viability measurements using MTT assay, all the tested compounds showed dose-dependent cytotoxic activity against HCT 116 cells. The tested compounds demonstrated significant activity with IC₅₀ values range 0.29–3.30 μM for HCT 116 and % age inhibition 6.37–21.00 for DPPH antioxidant study. 5-Fluorouracil was used as standard drug (IC₅₀ 19.2 μM for HCT 116) whereas for DPPH analysis, Gallic acid was used as positive control (% age inhibition 77.68). All the compounds showed potential anticancer activity against human colorectal cancer whereas antioxidant activity was not significant. We found that as the size of N-alkyl substitution on benzimidazolium salt increases its cytotoxicity against cancer decreases whereas a reverse occurs in case of respective complexes.     

MicroRNA‐33a‐5p suppresses colorectal cancer cell growth by inhibiting MTHFD2

Colorectal cancer (CRC) is one of the most common malignancies with high levels of invasiveness, drug resistance and mortality, but the internal mechanisms of CRC are largely unknown. MicroRNAs (miRs) have been reported to be involved in the development of CRC, and numerous studies have demonstrated that the abnormal expression of miR‐33a‐5p might be associated with CRC. However, the function and downstream mechanism of miR‐33a‐5p in colorectal cancer (CRC) remains unclear. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2), a mitochondrial enzyme involved in folic acid metabolism, interestingly was confirmed to be one of the target genes of miR‐33a‐5p in the present study. We first confirmed that miR‐33a‐5p in CRC tissues and cell lines were downregulated (P < 0.05), and that the proliferation, clone formation capacities, G1/S progression, and migration capacities of the two CRC cell lines HCT116 cells and HT29 were suppressed by miR‐33a‐5p overexpression in vitro (P < 0.05). Ctrl HCT116 and miR‐33a‐5p‐overexpressing HCT116 were injected into nude mice. In vivo tumour formation was significantly suppressed by miR‐33a‐5p overexpression (P < 0.05) as well as the proliferation marker Ki67 (P < 0.05). Additionally, MTHFD2 protein expression was significantly enhanced in CRC tissues. From bioinformatics predictions and a luciferase report analysis, MTHFD2 was confirmed to be one of the target genes of miR‐33a‐5p. In contrast to the role of miR‐33a‐5p overexpression, MTHFD2 overexpression promoted the proliferation and migration of HCT116 and HT29 cells (P < 0.05), which confirmed that MTHFD2 was a functional target gene of miR‐33a‐5p. In conclusion, miR‐33a‐5p inhibits the growth and migration of CRC by targeting MTHFD2.     

Hybrid liposomes showing enhanced accumulation in tumors as theranostic agents in the orthotopic graft model mouse of colorectal cancer

Hybrid liposomes (HLs) can be prepared by simply sonicating a mixture of vesicular and micellar molecules in a buffer solution. This study aimed to elucidate the therapeutic effects and ability of HLs to detect (diagnosis) cancer in an orthotopic graft mouse model of colorectal cancer with HCT116 cells for the use of HLs as theranostic agents. In the absence of a chemotherapeutic drug, HLs exhibited therapeutic effects by inhibiting the growth of HCT116 colorectal cancer cells in vitro, possibly through an increase in apoptosis. Intravenously administered HLs also caused a remarkable reduction in the relative cecum weight in an orthotopic graft mouse model of colorectal cancer. A decrease in tumor size in the cecal sections was confirmed by histological analysis using HE staining. TUNEL staining indicated an induction of apoptosis in HCT116 cells in the orthotopic graft mouse model of colorectal cancer. For the detection (diagnosis) of colorectal cancer by HLs, the accumulation of HLs encapsulating a fluorescent probe (ICG) was observed in HCT116 cells in the in vivo colorectal cancer model following intravenous administration. These data indicate that HLs can accumulate in tumor cells in the cecum of the orthotopic graft mouse model of colorectal cancer for a prolonged period of time, and inhibit the growth of HCT116 cells.     

Expression of domains for protein–protein interaction of nucleotide excision repair proteins modifies cancer cell sensitivity to platinum derivatives and genomic stability

Nucleotide excision repair (NER) is involved in the repair of DNA damage caused by platinum derivatives and has been shown to decrease the cytotoxic activity of these drugs. Because protein–protein interactions are essential for NER activity, we transfected human cancer cell lines (A549 and HCT116) with plasmids coding the amino acid sequences corresponding to the interacting domains between excision repair cross‐complementation group 1 (ERCC1) and xeroderma pigmentosum, complementation group A (XPA), as well as ERCC1 and xeroderma pigmentosum, complementation group F (XPF), all NER proteins. Using the 3‐(4,5‐dimethyl‐2 thiazoyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT) assay and annexin V staining, we showed that transfected A549 cells were sensitized 1.2–2.2‐fold to carboplatin and that transfected HCT116 cells were sensitized 1.4–5.4‐fold to oxaliplatin in vitro. In addition, transfected cells exhibited modified in vivo sensitivity to the same drugs. Finally, in particular cell models of the interaction between ERCC1 and XPF, DNA repair was decreased, as evidenced by increased phosphorylation of the histone 2AX after exposure to mitomycin C, and genomic instability was increased, as determined by comparative genomic hybridization studies. The results indicate that the interacting peptides act as dominant negatives and decrease NER activity through inhibition of protein–protein interactions.     

Synthesis,in‐vitro Cytotoxicity,and a Preliminary Structure‐Activity Relationship Investigation of Pyrimido[4,5‐c]quinolin‐1(2H)‐ones

As part of our ongoing research effort to develop new antimitotic agents based on the recently reported pyrimido[4,5‐c]quinoline‐1(2H)‐one ring skeleton, we were interested in identifying structural elements that contribute to the cytotoxicity of this class of compounds. The effect of several quinoline‐ring substituents was examined and the new compounds were evaluated in vitro for cytotoxicity against three human cancer cell lines namely, lung fibrosarcoma HT‐1080, colon adenocarcinoma HT‐29, and breast carcinoma MDA‐MB‐231. Most of the compounds showed cytotoxic activity in the low micromolar and sub‐micromolar range. Structure‐activity relationship information revealed that a combination of electronic and steric factors may be involved. Flow cytometric cell cycle analysis performed on HT‐1080 cells revealed that the most cytotoxic compounds 48 , 50 , 54 , 59 , and 63 inhibit the S‐phase and arrest the cells in the G2/M phase of the cell cycle suggesting an antimitotic action of these compounds.     

Design,Synthesis, and Antitumor Activity of 4-Halocolchicines and Their Pro-drugs Activated by Cathepsin B

相似文献   

Synthesis and Evaluation of Cleistanthin A Derivatives as Potent Vacuolar H+‐ATPase Inhibitors

Twelve new glycosides and alkane derivatives of cleistanthin A were designed and synthesized. Their in vitro antiproliferative activity was investigated against HCT‐116, HepG2, A549, Hela tumor cell lines and HEK293 cell by MTT assay. Most of these compounds displayed antiproliferative effects on four cancer cells at submicromolar concentration, but they were less potent than cleistanthin A Moreover, they showed no antiproliferative effects on HEK293 cell at 200 nm . The most potent compounds, 3e and 4a , have been shown to inhibit the activity of vacuolar H⁺‐ATPase (V‐ATPase) and neutralize the pH of lysosomes at submicromolar concentrations.     

Anti-tumor activity of new artemisinin-chalcone hybrids

In an attempt to develop potent and selective anti‐tumor agents, three new series of artemisinin–chalcone hybrids 10a – 10g , 11a – 11g and 12a–12h were designed, synthesized and screened for their anti‐tumor activity against five cell lines (HT‐29, A549, MDA‐MB‐231, HeLa and H460) in vitro. Among compounds 10a–g and 11a–11g , most of them displayed enhanced activity and good selectivity toward HT‐29 and HeLa cell lines with IC₅₀ values ranging from 0.12 to 0.85 µM as compared with DHA (dihydroartemisinin). Compounds 10a and 11a are most active toward HeLa cells with IC₅₀ values of 0.12 and 0.19 µM. The results revealed that the presence of chalcone moiety is beneficial to their activity and selectivity. In addition, compounds 12a ‐ 12h containing a ‘reversed chalcone’ moiety showed only slight improvement in activity than those of DHA.     

Inhibition of microRNA‐21‐3p suppresses proliferation as well as invasion and induces apoptosis by targeting RNA‐binding protein with multiple splicing through Smad4/extra cellular signal‐regulated protein kinase signalling pathway in human colorectal cancer HCT116 cells

MicroRNA‐21‐3p (miR‐21‐3p), the passenger strand of pre‐mir‐21, has been found to be high‐expressing in various cancers and to be associated with tumour malignancy, which is proposed as a novel focus in malignant tumours. Colorectal cancer (CRC), currently known as one of the most prevalent malignancy, is a leading cause of cancer death. This study aimed to investigate the key role of miR‐21‐3p in CRC by inhibiting its expression using transfection with miR‐21‐3p inhibitors into human CRC HCT116 cells. Results showed that the expression of miR‐21‐3p was higher than other CRC cells used in the study including Lovo, HT29, Colo320 and SW480 cells, inhibition of which suppressed the proliferation and induced cell cycle arrest in HCT116 cells. Besides, transfection with miR‐21‐3p inhibitors also attenuated cell migration and invasion, and induced apoptosis as well. Moreover, luciferase assay confirmed RBPMS as a direct target of miR‐21‐3p in HCT116 cells. Further, miR‐21‐3p inhibitors increased the nuclear accumulation of Smad4 and reduced phosphorylation of ERK. Interestingly, we found that silence of RBPMS using RNA interference (siRNA) not only elevated the cell viability but also increased the phosphorylation of ERK and reversed the nuclear accumulation of Smad4 induced by miR‐21‐3p inhibitors in HCT116 cells. Data suggest that inhibition of miR‐21‐3p suppresses cell proliferation, invasion as well as migration and induces apoptosis by directly targeting RBPMS through Smad4/ERK signalling pathway in HCT116 cells. Our study demonstrates miR‐21‐3p as a potent target for suppressing tumour progression of CRC which may have implications in CRC therapy in the future.     

Synthesis and anticancer activity of para-xylyl linked bis-benzimidazolium salts and respective Ag(I) N-heterocyclic carbene complexes

The article describes synthesis, characterization (NMR, FT-IR, microanalysis, X-ray crystallography), and in vitro anticancer activity of para-xylyl linked bis-benzimidazolium salts and respective dinuclear Ag–NHC complexes. All the compounds were tested for their cytotoxicity against human colorectal cancer (HCT 116) and promyelocytic leukemia (HL-60) cell lines. According to cell viability measurements using MTT assay, all tested compounds showed dose-dependent cytotoxic activity against both cell lines. The tested compounds demonstrated significant activity with IC₅₀ values range 0.01–18.7 μM for HCT 116 and 0.7–55.7 μM for HL-60 cells. 5-Fluorouracil was used as standard drug (IC₅₀ 19.2 μM for HCT 116 and 5.4 μM for HL-60). We found that as the size of N-alkyl substitution on benzimidazolium salt increases its cytotoxicity decreases whereas a reverse occurred in case of respective complexes.     

Synthesis and biological evaluation of novel hydrazide based cytotoxic agents

Recently, we designed and synthesized a series of pyrroloquinoxaline compounds with hydrazine moiety linking a nitrogen-containing polycyclic group to a heteroaroyl system. Several derivatives, with attractive drug-like properties, were identified as promising cytotoxic agents, showing excellent potency in a panel of cancer cell lines. In the current study, we synthesized a further 19 new analogues to optimize their physicochemical properties and assess a coherent mechanism of action. Several chemical modifications were made to the reference compounds by varying the fused-ring system and/or the heteroacyl moiety. To evaluate their in vitro activity, we tested these compounds in six human cancer cell lines derived from different origins. Among them, two compounds ( and ) showed similar potency as the reference compounds with IC₅₀ values in the sub-micromolar range in all cell lines tested. Furthermore, compound showed excellent in vivo efficacy in our preliminary human ovarian cancer mouse xenograft studies. Flow cytometric studies indicated that both derivatives interrupted cell cycle progression in colorectal cancer HCT116 cell lines and ovarian cancer SKOV-3 cells. Further mechanistic studies revealed that and were able to induce reactive oxygen species in SKOV-3 cells with apparently different kinetic patterns. Considering their cytotoxicity profiles in a variety of in vitro and in vivo cancer models, these hydrazide based compounds seem to have considerable potentials as novel chemotherapeutics.     

Anticancer effects of seaweed compounds fucoxanthin and phloroglucinol,alone and in combination with 5-fluorouracil in colon cells

ABSTRACT

Colorectal cancer therapy with 5-fluorouracil (5-Fu) frequently become ineffective due to resistance to this drug; and thus other effective compounds are essential for therapy. It is well-known marine brown seaweeds contain antioxidant compounds the carotenoid fucoxanthin (Fx) and polyphenolic compound phloroglucinol (Ph) which exerted diverse biological activities including antioxidant and anticancer. The aim of this study was to determine the anticancer activities of Fx or Ph alone as well as combination of each chemical with 5-Fu on two human colorectal cancer cell lines (HCT116 and HT29), with comparison to responses in a normal colon cell line (CCD-18Co). Effects of these compounds on cell viability, induction of DNA damage, and cell death were evaluated using MTT assay, comet assay, nuclear condensation assay, and Western blot. 5-Fu decreased cell viability in a concentration-dependent manner in HCT116 and HT29 cells but was not cytotoxic in CCD-18Co cells. 5-Fu induced DNA damage in HCT116 cells with induction of cell death, while no marked effects on DNA damage and cell death were observed in HT29 cells. Fx or Ph alone also reduced cell viability in both cancer cell lines but no apparent cytotoxic effect in CCD-18Co cells, except for Fx at 50 and 100 µM. Diminished cell viability was accompanied by induction of DNA damage (by Fx) and induction of cell death (by Ph). In combination with 5-Fu, Fx at 10 µM (in HCT116 and HT29 cells), and Ph at 300 µM (in HT29 cells) enhanced the cytotoxic effect of 5-Fu; however, no marked cytotoxicity was noted in CCD-18Co cells. Since Fx and Ph alone reduced cancer cell line viability without an effect on normal cells and when in combination enhanced the cytotoxic effect of 5-Fu only in colon cancer cells, these compounds seem promising as anticancer agents.     

Modulation of Imatinib Cytotoxicity by Selenite in HCT116 Colorectal Cancer Cells

Imatinib is a principal therapeutic agent for targeting colorectal tumours. However, mono‐targeting by imatinib does not always achieve complete cancer eradication. Selenite, a well‐known chemopreventive agent, is commonly used in cancer patients. In this study, we aimed to explore whether selenite can modulate imatinib cytotoxicity in colorectal cancer cells. HCT116 cells were treated with different concentrations of imatinib and/or selenite for 24, 48 and 72 hr. Imatinib–selenite interaction was analysed using isobologram equation. As indicators of apoptosis, DNA fragmentation, caspase‐3 activity, Bcl‐2 expression were explored. Autophagic machinery was also checked by visualizing acidic vesicular organelles and measuring Beclin‐1 expression. Furthermore, reactive oxygen and nitrogen species were also examined. This study demonstrated that selenite synergistically augmented imatinib cytotoxicity in HCT116 cells as demonstrated by combination and dose reduction indices. Supranutritional dose of selenite when combined with imatinib induced apoptotic machinery by decreasing Bcl‐2 expression, increasing caspase‐3 activity and subsequently fragmenting DNA and blunted cytoprotective autophagy by decreasing Beclin‐1 expression and autophagosomes formation. Moreover, their combination induced cell cycle S‐phase block, increased total thiol content and reduced nitric oxide levels. In conclusion, selenite synergizes imatinib cytotoxicity through multi‐barrelled molecular targeting, providing a novel therapeutic approach for colorectal cancer.