Colon Cancer Cell Line HCT-8 Research Articles

Streamlining RNA Aptamer Selection via Unique Molecular Identifiers and High-Throughput Sequencing.

Aptamers are valuable tools for applications such as cell imaging, drug delivery, and therapeutics. RNA aptamers, in particular, exhibit complex structural diversity and flexibility, affording higher affinity and specificity, broader target recognition, and easier chemical modification compared with DNA aptamers. However, traditional selection methods for RNA aptamers are time-consuming and involve numerous rounds of screening, thus limiting their widespread application. To overcome this challenge, we propose an efficient truncated selection approach termed ID-SELEX. This method incorporates a molecular identification marker whereby each template is labeled with a unique molecular identifier, or UMI. Such incorporation helps mitigate biases introduced by multiple polymerase chain reaction (PCR) amplification during high-throughput sequencing, ensuring accurate identification of aptamer candidates. Utilizing ID-SELEX, we successfully identified a panel of high-quality aptamers targeting the human colon cancer cell line HCT-8 in just 2 rounds of selection. Furthermore, we demonstrated the versatility of this strategy by selecting 6 RNA aptamers targeting mouse myoblast cell line C2C12 with only one round of selection. In summary, RNA aptamer selection based on ID-SELEX utilizes high-throughput sequencing and UMI labeling to enable the rapid screening of RNA aptamers across human and murine cell lines. As such, ID-SELEX has the potential to facilitate RNA aptamer discovery, providing a novel molecular tool for biomedical research, clinical applications, and precision medicine.

Effect of RNA interference targeting neuropilin-2 gene on proliferation and apoptosis of colon cancer cell line HCT-8

Objective: To investigate the effects of down-regulation of expression of neuropilin-2 (NRP-2) by RNA interference (RNAi) technique on proliferation and apoptosis of HCT-8 colon cancer cells. Methods: NRP2-siRNA and negative control (NControl)-siRNA were transferred into HCT-8 colon cancer cells by liposomes (lip2000) as transfection group and negative control group, and phosphate buffered solution (PBS) was added as blank control group. Quantitative reverse transcription PCR (RT-qPCR) and Western blot were used to detect the transfection effect. The proliferation of cells in the three groups was examined by cell counting kit (CCK) assay, colony-forming unit assay and Ki-67 protein staining assay, respectively. Moreover, the apoptosis of cells in the three groups was determined by acridine orange/propranidine iodide (AO/PI) staining method. Results: The results of RT-qPCR and Western blot showed that the relative expression of NRP-2 mRNA and the content of NRP-2 protein in the transfer group decreased (0.46±0.05 vs 0.99±0.05 and 1.00±0.06; 1.04±0.06 vs 1.73±0.09 and 1.65±0.11) (all P<0.05). The results of CCK-8 demonstrated that the optical density of transfection group was significantly lower than that of the negative control group and the blank control group(24 h: 0.53±0.04 vs 0.82±0.07 and 0.87±0.07; 48 h: 0.54±0.05 vs 1.00±0.09 and 1.17±0.05; 72 h: 0.75±0.05 vs 1.31±0.13 and 1.50±0.03; 96 h:1.05±0.04 vs 1.46±0.09 and 1.86±0.06) (all P<0.05). The results of colony-forming unit assay indicated that the proliferation ability of the cells in the transfer group was significantly lower than that in the other two groups (134.67±8.74 vs 245.33±19.14 and 300.33±14.01, P<0.05). The results of Ki-67 protein staining assay showed that compared with the negative control group and blank control group, the expression of Ki-67 protein was significantly decreased in the transfection group (5.93±0.22 vs 8.36±0.09 and 8.70±0.21, P<0.05). The results of AO/PI assay revealed that the ratio of apoptotic cells to living cells in the transfer group was significantly higher than that in the other two groups (0.43±0.07 vs 0.14±0.04 and 0.11±0.04, P<0.05). Conclusion: The proliferation ability of HCT-8 colon cancer cells decreases, and the apoptosis ability increases by decreasing the expression of NRP-2.

Production and characterization of exopolysaccharides from Chlorella zofingiensis and Chlorella vulgaris with anti-colorectal cancer activity

The production, physicochemical characteristics, antioxidant and antitumor activities of partial purified exopolysaccharides from Chlorella zofingiensis, Chlorella vulgaris were investigated. The final exopolysaccharides productions were 208.4, 364.3 mg/L and the average molecular weights were 2.66×104, 1.88×104 Da, respectively. Monosaccharide analysis indicating that these exopolysaccharides consisted of 10 or 11 different kinds of sugars and derivatives, respectively. Additionally, they exhibited obvious radical scavenging activities on DPPH and hydroxyl radicals, which reached to 59.6–71.5% and 44.5–70.4%, respectively. Moreover, the antitumor effects were studied using human colon cancer cell lines HCT8. The results showed that they had significant antitumor effects considering the inhibitory effects on cell viabilities (28.3–18.0% on HCT8, respectively). Thus, these exopolysaccharides from microalgae species are worth further investigating as alternative potential antitumor agents.

Downregulation of DBN1 is related to vincristine resistance in colon cancer cells.

This study was aimed to investigate the relationship between the expression of drebrin (DBN1) gene and resistance in colon cancer to reveal the mechanism of tumor drug resistance and provide a basis for the reversal of this drug resistance in tumor cells. The human colon carcinoma cell line HCT-8 was used, and vincristine (VCR)-resistant colon cancer cell line HCT-8/V was established by gradually increasing the concentration of VCR. Polymerase chain reaction (PCR) primers were designed for DBN1 gene. The DBN1 differential expression in colon cancer sensitive and resistant cell lines was detected by fluorescence quantitative PCR. Western blot analysis was used to study DBN1 expression in the resistant cells further. VCR resistance of HCT-8/V cell line was established. Quantitative PCR and Western blot results showed that DBN1 expression in the resistant cell line was significantly lower, the difference being statistically significant (P < 0.05). Low DBN1 gene expression may be associated with colon cancer cell resistance to VCR.

Abstract 5840: Inhibition of cystathionine-β-synthase (CBS) sensitizes colon cancer cells to 5-FU via increasing apoptosis and inhibiting cellular bioenergetics

Abstract Increased expression of cystathionine-β-synthase (CBS) has been validated in multiple kinds of tumor tissues, including colorectal cancer. Endogenous hydrogen sulfide (H2S), produced by CBS, was able to promote the proliferation and migration of colon cancer cells by inhibiting apoptosis and injuries caused by noxious environmental factors, including chemotherapeutic agents. Recently, overexpression of CBS has been reported to play a pivotal role in tumorigenesis of colon cancer cells, rendering the normal colon epithelial cell line acquiring the features of malignant cells. However, the potential role of CBS in the development of chemoresistance of colon cancer cells has not be illustrated. In the present study, overexpression of CBS in tumor tissues was further validated by realtime PCR and the effect of inhibition of both the activity and expression of CBS on the sensitivity to 5-fluorouracil (5-FU) was investigated in colon cancer cell lines. Inhibition of the activity of CBS by CBS inhibitor aminooxyacetate (AOAA) significantly increased the sensitivity of colon cancer cell lines to 5-FU, featured by decreased IC50 and colony forming efficiency. However, utilizing a slowly releasing H2S donor GYY4137, the present study suggested that exogenous hydrogen sulfide was able to increase the resistance to 5-FU in both colon cancer cell lines. What's intriguing was that, 5-FU, at clinically relevant concentrations, significantly inhibited the expression of CBS. Co-treatment of AOAA significantly increased the expression of Bax and decreased the expression of Bcl-2, indicating the involvement of increased apoptosis. AOAA also predisposed the colon cancer cells to the inhibition of cellular energetics induced by 5-FU, featured by the further reduced level of cellular ATP. These results suggested that inhibition of CBS promoted the sensitivity of colon cancer cells to 5-FU via increasing apoptosis and inhibiting cellular bioenergetics. Furthermore, inhibition of CBS expression by shRNA sensitizes the 5-FU resistant colon cancer cell line HCT-8/5-FU to treatment with 5-FU. The increased expression of CBS and the consequently increased level of endogenous H2S might be a potential therapeutic target for chemoresistance in colon cancer. Citation Format: Shanwen Chen, Pengyuan Wang, Yisheng Pan, Yucun Liu. Inhibition of cystathionine-β-synthase (CBS) sensitizes colon cancer cells to 5-FU via increasing apoptosis and inhibiting cellular bioenergetics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5840.

P0224 A novel, small molecule inhibitor, MSU-1001, in androgen-sensitive prostate cancer cell lines

Introduction Prostate cancer is one of the leading causes of cancer-related death in men worldwide. Current treatment options are limited to traditional chemotherapy, surgery, radiation, or hormone therapy, which often have unwanted side effects. There is a need to develop safer molecules that attenuate tumour progression without adversely affecting the overall quality of life. We report the in vitro activity of a novel, synthetic, small molecule, with potential to be a lead candidate for the treatment of prostate cancer. Methods A library of novel small molecule inhibitors was developed through rational drug design. A pyrrolo-pyrimidine derivative (MSU-1001) was identified as a potential lead molecule. Prostate and colon cancer cell lines (LNCap, HT-29, and HCT-8) were obtained from the American Type Culture Collection (ATCC). Cells were incubated with various concentrations of MSU-1001 for 72 h. Growth inhibition was determined colorimetrically on a plate-reader using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. Findings Colon cancer cell lines HCT-8 and HT-29 were used in conjunction with the androgen-sensitive human prostate adenocarcinoma cell line, LNCaP, to investigate the specificity of MSU-1001 on tumour type. Among the library of compounds tested, MSU-1001 was pursued based on its anti-proliferative activity in LNCaP cells. Addition of MSU-1001 to LNCaP cells resulted in a dose-dependent inhibition of proliferation (GI 50 = 161 nM) with a near-complete inhibition of cell growth noted at 10 μM. By contrast, GI 50 of gemcitabine was more than 6-fold higher (GI 50 = 1.21 μM) in LNCaP cells. Additionally, GI 50 of MSU-1001 in HCT-8 and HT-29 was 1.8 and 8.7 μM, respectively, indicating relative specificity of MSU-1001 against prostate cancer. Interpretation These data show the therapeutic potential of MSU-1001 in prostate cancer. Combination studies of MSU-1001 with testosterone, 17 β -estradiol, and dehydroepiandro-stenone in androgen-sensitive and insensitive prostate cancer cell lines are currently ongoing.

FTY720 enhances chemosensitivity of colon cancer cells to doxorubicin and etoposide via the modulation of P-glycoprotein and multidrug resistance protein 1.

This study aimed to investigate the effects of FTY720 on inducing cell growth inhibition and enhancing the cytotoxicity of anti-cancer drugs in the human colon cancer cell line HCT-8 and its multidrug-resistant cell line HCT-8/5-fluorouracil (HCT-8/5-Fu). Cell viability and apoptosis after being treated with FTY720 alone or in combination with doxorubicin (DOX) and etoposide (VP16) were tested in HCT-8 and HCT-8/5-Fu cells. The changes in P-glycoprotein (P-gp) and multidrug resistance protein 1 (MRP1) were determined at the mRNA and functional levels. FTY720 showed anti-proliferative activity against cancer cells in a dose-dependent and time-dependent manner and could enhance the cytotoxicity of DOX and VP16 in both HCT-8 and HCT-8/5-Fu cell lines. In addition, treatment with FTY720 resulted in the promotion of VP16-induced cell apoptosis and an increased accumulation of intracellular DOX and two specific fluorescent substrates of P-gp and MRP1 through the inhibition of efflux and the suppression of gene expression. FTY720 exerts its chemosensitization effect in HCT-8 and HCT-8/5-Fu cell lines by promoting cell apoptosis and inhibiting P-gp and MRP1, which could be applied as a potential co-adjuvant therapeutic modality.

Some new quinazolin-4(3H)-one derivatives, synthesis and antitumor activity

A series of some new 2,3-disubstituted-6-iodo-3H-quinazolin-4-one derivatives was prepared and screened for their in vitro antitumor activity against the human breast cancer cell line (MCF-7), human cervix carcinoma cell line (HeLa), human liver cancer cell line (HepG2) and human colon cancer cell line HCT-8. Five compounds exhibited broad spectrum antitumor activity, better than the standard drug Doxorubicin (CAS-23214-92-8) against the four tested cell lines. In the present study, MCF-7 cell line was the most sensitive one, 12 compounds were good cytotoxic towards it. The best cytotoxic results were obtained with compounds bearing allyl and/or benzyl moiety at positions 2 and/or 3 of the quinazoline nucleus.

Dual role of insulin-like growth factor-1 in acetyl-CoA carboxylase-alpha activity in human colon cancer cells HCT-8: downregulating its expression and phosphorylation

Insulin-like growth factor-1 (IGF-1) plays the role in cellular lipid synthesis and cell proliferation. However, the role of IGF-1 on the growth of colon cancer cell line HCT-8 is not clear. In this study, HCT-8 cells were exposed to IGF-1 at 0, 10, 50, or 100 ng/ml in serum-free medium. Fatty acid/lipid synthesis in HCT-8 cells was examined by 2-14C-acetate incorporation. HCT-8 cell growth and proliferation were determined by MTT assay and Trypan blue exclusive viable cell counting. We found that in serum starvation conditions, IGF-1 at 10-100 ng/ml induced dose-dependent down regulation of both the ACCα expression and the phosphorylation in HCT-8 cells, maintaining a balance in ACCα activity and lipid synthesis. IGF-1 reduced p-ATM, p-AMPK, and then p-ACCα protein levels in HCT-8 cells. IGF-1 increased p-Akt levels, but decreased p-ERK1/2 levels, leading to the decrease in ACCα protein and mRNA levels. Similarly, ERK1/2 inhibitor PD98059 reduced ACCα expression. IGF-1 influences neither HCT-8 cell growth nor their p53 protein levels and PARP cleavage. In a word, IGF-1 reduced ACCα phosphorylation via an ATM/AMPK signaling pathway and suppressed ACCα expression through an ERK1/2 transduction, playing a dual role in regulating ACCα activity and lipogenesis. This may render a cell with survival advantages under a serum starvation crisis, representing a novel mitogenic role of IGF-1.

Insulin induces anticancer cytotoxicity of 5-Fu to two human colon cancer cell lines

To explore the possibility of use of insulin as a potentiator of 5-Fu to human colon cancer cell lines HCT-8 and HT-29 and study its mechanism. MTT assay was used to examine the inhibition rate of cell growth after treatment with 5-Fu and insulin. Cell cycle was determined by flow cytometry. Insulin showed an enhancing effect on the chemotherapeutic response of 5-Fu when insulin was applied at a dose of exceeding 0.8 mU/ml 0 approximately 8 h before 5-Fu. Within the range of from 0.8 mU/ml to 8 mU/ml, a higher concentration of insulin gave a higher proportion of inhibited cells. But when the insulin concentration exceeds 8 mU/ml, the proportion became stable as that of 8 mU/ml. Insulin increased the percentage of S phase cells and decreased the percentage of G(1) phase cells (P < 0.01). The percentage of S phase cells reached a peak when the cells were treated with insulin for 6 hours. Insulin can enhance the anticancer toxicity of 5-Fu to human colon cancer cell lines HCT-8 and HT-29 cells. Insulin increases the percentage of S phase cells, which may be one of the main mechanisms of insulin-induced enhancement of anticancer response of cancer cells to 5-Fu chemotherapy.

HMSH6 deficiency and inactivation of the alphaE-catenin invasion-suppressor gene in HCT-8 colon cancer cells.

Transition from an epithelioid (E) to a round (R) morphotype, in the human colon cancer cell line HCT-8, is associated with loss or truncation of alphaE-catenin and acquisition of invasiveness in organ culture. In E clones, like in parental HCT-8 cells, one allele of the alphaE-catenin gene (CTNNA1) is mutated. HCT-8 cells have also a 'Microsatelite Instability-High' (MSI-H) phenotype presumably due to a mutated hMSH6 gene. Fusion of E type cells doubles the wild type CTNNA1 alleles and prevents the loss of alphaE-catenin. Introduction of an extra chromosome 2, carrying a wild type hMSH6 gene, restores post-replicative mismatch repair and also prevents the frequent inactivation of the remaining wild type CTNNA1 allele.