Proliferation Of Colon Cancer Cells Research Articles

Expanded targeting scope of LbCas12a variants allows editing of multiple oncogenic mutations

RNA-guided CRISPR-Cas12a endonucleases are promising tools for genome engineering. Here we demonstrate that LbCas12a variants derived from Lachnospiraceae bacterium show a broad PAM preference, recognizing certain non-canonical PAMs with high efficiency. Furthermore, we engineered LbABE8e to carry G532R and/or K595R mutations, altering its original PAM specificities; these variants exhibited superior base editing activity in human cells compared with wild-type LbABE8e at sites with non-canonical PAMs. Based on this finding, we utilized the most effective LbCas12a and LbABE8e variants to demonstrate multiplexed and mutant-allele-specific gene editing in oncogenes, made possible by the variant’s recognition of non-canonical PAMs. Importantly, LbCas12a-G532R/K595R and LbABE8e-G532R/K595R with optimized crRNA arrays targeted to triple oncogenic mutations inhibited colon cancer cell proliferation. Taken together, these results demonstrate the potential of engineered LbCas12a and LbABE8e as tools for targeting sites with alternative PAMs for genome engineering and therapeutic editing in cancer cells.

CCL26 silence represses colon cancer by inhibiting the EMT signaling pathway

This study aimed to determine the expression and investigate the role of chemokine 26 (CCL26) in colon cancer cells. The Cancer Genome Atlas (TCGA) analysis, qRT-PCR, and western blotting were used to detect CCL26 expression while the Kaplan-Meier plotter was used to analyze the survival of patients with colon cancer. Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and Transwell assays were performed to measure the viability, proliferation, apoptosis, and migration and invasion of colon cancer cells, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) was used to analyze the signaling pathways regulated by CCL26. Western blotting, used to measure protein expression in this study, found overexpression of CCL26 in colon tumors. Low CCL26 levels were associated with better survival of patients as CCL26 siRNAs markedly reduced viability and proliferation, accelerated apoptosis, decreased migration and invasion, enhanced E-cadherin expression, and reduced N-cadherin and vimentin expression in cancer cells. The opposite results were obtained in CCL26-overexpressed colon cancer cells. In addition, CCL26 activated the epithelial-mesenchymal transition (EMT) pathway. CCL26 siRNAs suppressed the expression of tissue inhibitor matrix metalloproteinase 1 (TIMP1), nicotinamide N-methyltransferase (NNMT), and fibromodulin (FMOD), while CCL26 overexpression significantly increased the expression of all. EMT inhibition using the EMT inhibitor C19 eliminated the effect of CCL26 overexpression on colon cancer cells. In summary, CCL26 is involved in colon cancer progression through regulation of the EMT signaling pathway.

Effect of Kaempferol on the Biological Behavior of Human Colon Cancer via Regulating MMP1, MMP2, and MMP9

Kaempferol is a kind of flavonoid, which has a significant anticancer effect. MMPs were discovered with the function of cleaving the extracellular matrix. We utilized bioinformatics to analyze the association and bonding mode between the traditional Chinese medicine (TCM) monomer composition (i.e., kaempferol) and the target proteins. The purpose of our research was to verify the effect of kaempferol on the biological behavior of human colon cancer cells HCT116 and HT29 and the expression of matrix metalloproteinase (MMP) 1, 2, and 9 genes. We detected the changes in the biological behavior of colon cancer cells treated with kaempferol by CCK-8, wound healing assay, transwell migration/invasion assay, and flow cytometry. Meanwhile， we detected the expression difference of the target gene by qRT-PCR and western blot. Compared with the two control groups, the cell viability of the kaempferol group decreased, the rate of cell migration and the number of transmembrane cells in the kaempferol group decreased significantly, and the early apoptosis rate increased, the number of cells in the G1 phase increased and in the S phase decreased. The results of qRT-PCR and western blot showed that the expression of target genes MMP1, 2, and 9 in the kaempferol group was lower than that in the two control groups. Kaempferol can significantly inhibit the proliferation, invasion, and migration ability of colon cancer cells; induce their apoptosis; and block the cell cycle. Meanwhile, the expression of MMP1, 2, and 9 genes was downregulated, which verified the results of bioinformatic analysis.

Gold nanoparticles (AuNPs) and Rosmarinus officinalis extract and their potentials to prompt apoptosis and arrest cell cycle in HT-29 colon cancer cells

BackgroundOne of the significant morbidity and mortality causes is the colorectal cancer. Rosmarinus officinalis plant is utilized as food and medicine. Currently, nanoparticles are widely employed in medicinal preparations. This work aimed to explore the potentials of R. officinalis leaves acetone extract, alone or in combination gold nanoparticles (AuNPs), to kill colon cancer cells. MethodsFresh leaves of R. officinalis were collected from the Al Soudah, Saudi Arabia and then dried to prepare acetone extract. AuNPs were prepared utilizing the extract and portrayed using UV/Vis spectrophotometry and scanning electron microscopy (SEM). Active ingredients exist in the extract and extract + AuNPs were screened using FT-IR spectroscopy. Biological properties of the extract and extract + AuNPs including anti-cancer activity and apoptotic capacity were studied. ResultsResults of UV/Vis spectrophotometry and SEM demonstrated that AuNPs are of 79 nm in diameter. FTIR analysis revealed the existence of bioactive molecules in the extract. Extract and extract + AuNPs arrested HT-29 colon cancer cells at G2/M phase. ConclusionR. officinalis acetone extract and extract + AuNPs could arrest the proliferation of HT-29 colon cancer cells. Extract and extract + AuNPs actuated apoptosis in cancer cells as opposed to necrosis.

Chinese herbal medicine anticancer cocktail soup activates immune cells to kill colon cancer cells by regulating the gut microbiota-Th17 axis.

Chinese herbal medicines are effective for treating colon cancer (CC). CC development is reportedly associated with gut microbiota dysbiosis and immune function dysregulation. Herein we explored the therapeutic effects of a Chinese herbal medicine anticancer cocktail soup (CHMACS) on mice with CC and also explored its regulatory effects on gut microbiota. In vivo experiments indicated that CHMACS significantly inhibited the proliferation and tumorigenicity of CC cells. Further, CHMACS treatment decreased the proportion of CD8+ T, natural killer, and Th17 cells. HPLC/MS analysis showed that CHMACS comprised 227 active components. 16S rRNA sequencing revealed, for example, an increase in the relative abundance of uncultured_bacterium_g_Turicibacter and a decrease in that of uncultured_bacterium_g_Coriobacteriaceae_UCG-002 in gut microbiota of CHMACS-treated mice. Microbial diversity cluster analysis revealed that Verrucomicrobia, Spirochaetes, Fusobacteria, Patescibacteria, and Firmicutes contributed the most to fecal microbial diversity. Kyoto Encyclopedia of Genes and Genomes metabolic pathway analysis and clusters of orthologous groups of protein annotation indicated that CHMACS treatment induced amino acid metabolism and suppressed carbohydrate metabolism. Moreover, we found a strong association between changes in metabolites and immune cell maturation and activation. To summarize, our findings suggest that CHMACS kills CC cells by regulating gut microbiota and activating immune cells.

NAP1L1 promotes the growth of colon cancer by activating HDGF/DDX5.

Colon cancer is a common malignant tumor. However, its pathogenesis still needs further study. In this study, we explored the role of nucleosome assembly protein 1-like 1 (NAP1L1) in colon cancer and its underlying mechanism. Based on analysis of The Cancer Genome Atlas data, we found that NAP1L1 is augmented in colorectal cancer, and the elevated NAP1L1 expression is associated with a poor prognosis in patients with colon cancer. Immunohistochemistry staining results showed that upregulated NAP1L1 protein level is an unfavorable factor that stimulates colon cancer progression. To further investigate the role of NAP1L1 in colon cancer, we established a colon cancer cell line with NAP1L1 knockdown, and found that repressing NAP1L1 expression in colon cancer cells markedly reduces cell proliferation in vivo and in vitro by MTT assay, colony formation, EdU incorporation, and subcutaneous tumorigenesis in nude mice. Furthermore, we found that NAP1L1 binds to HDGF, recruits DDX5, and induces β-catenin/CCND1 signaling, which promotes colon cancer cell proliferation. Finally, transfection with HDGF or DDX5restores cell growth in NAP1L1-knockdown colon cancer cells by upregulating DDX5/β-catenin/CCND1 signaling. Our study demonstrates that NAP1L1 functions as a potential oncogene that promotes colon cancer tumorigenesis by binding to HDGF, which stimulates DDX5/β-catenin/CCND1 signaling.

Luteolin induces pyroptosis in HT-29 cells by activating the Caspase1/Gasdermin D signalling pathway.

Luteolin, which is a natural flavonoid, has anti-inflammatory, antioxidant, and anticancer properties. Numerous studies have proven that luteolin inhibits the growth of many types of cancer cells by promoting apoptosis, autophagy, and cell cycle arrest in tumour cells. However, in vivo research on this topic has been limited. In addition, other studies have shown that luteolin exerts a good inhibitory effect on apoptosis-resistant cancer cells. While existing studies have not completely elucidated the mechanism underlying this phenomenon, we assume that luteolin, which is a natural compound that exerts its effects through various mechanisms, may have the potential to inhibit tumour growth. In our study, we proved that luteolin exerted a good inhibitory effect on the proliferation of colon cancer cells according to CCK8 and EdU fluorescence assays, and the same conclusion was drawn in animal experiments. In addition, we found that luteolin, which is an antioxidant, unexpectedly promoted oxidative stress as shown by measuring the levels of oxidative balance-related indicators, such as reactive oxygen species (ROS), SOD, H2O2 and GSH. However, the decreased oxidation of luteolin-treated HT-29 cells after treatment with the active oxygen scavenger NAC did not reverse the inhibition of cell growth. However, the Caspase1 inhibitor VX765 did reverse the inhibition of cell growth. Western blotting analysis showed that luteolin treatment increased the expression of Caspase1, Gasdermin D and IL-1β, which are members of the pyroptosis signalling pathway, in colon cancer cells. We further intuitively observed NLRP3/Gasdermin D colocalization in luteolin-treated HT-29 cells and mouse tumour tissues by immunofluorescence. These results suggest that luteolin inhibits the proliferation of colon cancer cells through a novel pathway called pyroptosis. This study provides a new direction for the development of natural products that inhibit tumour growth by inducing pyroptosis.

Activation of DDX58/RIG‑I suppresses the growth of tumor cells by inhibiting STAT3/CSE signaling in colon cancer.

Some patients with colon cancer eventually develop metastasis during treatment, and the 5-year survival rate of patients with metastatic colon cancer remains relatively low, which is most likely due to the ineffectiveness of the current standard treatment. Systemic treatment for patients with colon cancer has expanded from chemotherapy to targeted therapy and immunotherapy. Immunotherapy holds promise in the treatment of colon cancer. The present study revealed the role of innate immune receptor helicase DExD/H-box helicase 58 (DDX58), which encodes retinoic acid-inducible gene-I (RIG-I), in colon cancer. It was demonstrated that colon cancer patients with a low protein expression of DDX58/RIG-I had a worse 5-year survival rate of patients compared with patients with a high expression of DDX58/RIG-I. The activation of DDX58/RIG-I inhibited the proliferation, migration and invasion of colon cancer cells, as well as tumor growth in a nude mouse xenograft model of colon cancer. To investigate the mechanisms of action of DDX58/RIG-I in colon cancer, the role of signal transducer and activator of transcription 3 (STAT3)/cystathionine-γ-lyase (CSE) signaling in the upor downregulation of DDX58 was examined. The data demonstrated that DDX58 regulated the STAT3/CSE signaling pathway by interacting with STAT3 and consequently affecting the proliferation of tumor cells in colon cancer. In addition, the RIG-I agonist, SB9200, induced proliferation, migration and invasion of human colon cancer. On the whole, the present study demonstrates that DDX58/RIG-I affects the proliferation of tumor cells by regulating STAT3/CSE signaling in colon cancer. The findings presented herein suggest that DDX58/RIG-I activation may be an effective treatment strategy, and DDX58/RIG-I agonists may be potential therapeutic candidates for colon cancer.

Novel prognostic model predicts overall survival in colon cancer based on RNA splicing regulation gene expression

Colon cancer is the third most common cancer and the second leading cause of cancer‐related death worldwide. Dysregulated RNA splicing factors have been reported to be associated with tumorigenesis and development in colon cancer. In this study, we interrogated clinical and RNA expression data of colon cancer patients from The Cancer Genome Atlas (TCGA) dataset and the Gene Expression Omnibus (GEO) database. Genes regulating RNA splicing correlated with survival in colon cancer were identified and a risk score model was constructed using Cox regression analyses. In the risk model, RNA splicing factor peroxisome proliferator‐activated receptor‐γ coactivator‐1α (PPARGC1) is correlated with a good survival outcome, whereas Cdc2‐like kinase 1(CLK1), CLK2, and A‐kinase anchor protein 8‐like (AKAP8L) with a bad survival outcome. The risk model has a good performance for clinical prognostic prediction both in the TCGA cohort and the other two validation cohorts. In the tumor microenvironment (TME) analysis, the immune score was higher in the low‐risk group, and TME‐related pathway gene expression was also higher in low‐risk group. We further verified the mRNA and protein expression levels of these four genes in the adjacent nontumor, tumor, and liver metastasis tissues of colon cancer patients, which were consistent with bioinformatics analysis. In addition, knockdown of AKAP8L can suppress the proliferation and migration of colon cancer cells. Animal studies have also shown that AKAP8L knockdown can inhibit tumor growth in colon cancer in vivo. We established a prognostic risk model for colon cancer based on genes related to RNA splicing regulation and uncovered the role of AKAP8L in promoting colon cancer progression.

Cannabidiol inhibits invasion and metastasis in colorectal cancer cells by reversing epithelial-mesenchymal transition through the Wnt/β-catenin signaling pathway.

Colorectal cancer (CRC) is the leading cause of cancer deaths worldwide, wherein distant metastasis is the main reason for death.The non-psychoactive phytocannabinoid cannabidiol (CBD) effectively induces the apoptosis of CRC cells. We investigated the role of CBD in the migration and metastasis of CRC cells. CBD significantly inhibited proliferation, migration, and invasion of colon cancer cells in a dose- or time-dependent manner. CBD could also inhibit epithelial-mesenchymal transition (EMT) by upregulating epithelial markers such as E-cadherin and downregulating mesenchymal markers such as N-cadherin, Snail, Vimentin, and HIF-1α. CBD could suppress the activation of the Wnt/β-catenin signaling pathway, inhibit the expression of β-catenin target genes such as APC and CK1, and increase the expression of Axin1. Compared to the control group, the volume and weight of orthotopic xenograft tumors significantly decreased after the CBD treatment. The results demonstrated that CBD inhibits invasion and metastasis in CRC cells. This was the first study elucidating the underlying molecular mechanism of CBD in inhibiting EMT and metastasis via the Wnt/β-catenin signaling pathway in CRC cells. The molecular mechanism by which CBD inhibits EMT and metastasis of CRC cells was shown to be through the Wnt/β-catenin signaling pathway for the first time.

Regulation of UHRF1 acetylation by TIP60 is important for colon cancer cell proliferation

BackgroundUbiquitin-like with PHD and RING finger domains 1 (UHRF1) is upregulated in colon cancer cells and associated with silencing tumor suppressor genes (TSGs) to promote colon cancer cell proliferation.ObjectiveTo investigate epigenetic modification of UHRF1 by TIP60. Whether UHRF1 acetylation by TIP60 can induce cell proliferation in colon cancer cells.MethodsAcetylation sites of UHRF1 by TIP60 was predicted by ASEB (Acetylation Set Enrichment Based) method and identified by immunoprecipitation assay using anti-pan-acetyl lysine antibody and in vitro acetylation assay. Based on this method, UHRF1 acetylation-deficient mimic 4KR (K644R, K646R, K648R, K650R) mutant was generated to investigate effects of UHRF1 acetylation by TIP60. shRNA system was used to generate stable knockdown cell line of UHRF1. With transient transfection of UHRF1 WT and 4KR, the effects of UHRF1 4KR mutant on Jun dimerization protein 2 (JDP2) gene expression, cell proliferation and cell cycle were investigated by RT-qPCR and FACS analysis in shUHRF1 colon cancer cell line.ResultsDownregulation of TIP60-mediated UHRF1 acetylation is correlated with suppressed cell cycle progression. Acetylation-deficient mimic of UHRF1 showed poor cell growth through increased expression of JDP2 gene.ConclusionsAcetylation of UHRF1 4K residues by TIP60 is important for colon cancer cell growth. Furthermore, upregulated JDP2 expression by acetylation-deficient mutant of UHRF1 might be an important epigenetic target for colon cancer cell proliferation.

Mesenchymal stem cells derived from adipose tissue accelerate the progression of colon cancer by inducing a MTCAF phenotype via ICAM1/STAT3/AKT axis.

Previous studies have shown that the risk of colon cancer is greatly increased in people with obesity, and fat content in colorectal cancer tissue is increased in people with obesity. As an important part of tumor microenvironment, adipose-derived mesenchymal stem cells (MSCs) are also another important source of cancer-associated fibroblasts (CAFs), which may be one of the important mechanisms of affecting tumor progression. However, the mechanism is poorly defined. In the present study, CAFs were transformed from MSCs [MSC-transformed CAFs (MTCAFs)] by co-culturing with HCT116 cells. Bioinformatics and Western blotting analysis indicated a positive correlation between intercellular adhesion molecule-1(ICAM-1) and the progression of colon cancer. In clinical colon cancer specimens, we found that ICAM-1 was highly expressed and related to shorter disease-free survival, which might act as an indication for the progression of clinical colon cancer. Our data showed that ICAM-1 secreted from MTCAFs could positively promote the proliferation, migration, and invasion of colon cancer cells by activating signal transducer and activator of transcription 3 (STAT3) and Serine/threonine-protein kinase (AKT) signaling and that blocking ICAM-1 in MTCAFs reversed these effects. We further verified that ICAM-1 secreted from MTCAFs promoted tumor progression in vivo. Taken together, ICAM-1 plays a critical role in regulating tumor growth and metastasis, which could be a potential therapeutic target in colon cancer.

Effects of Anesthetics on Proliferation and Apoptosis of Drug-Resistant Human Colon Cancer Cells.

In recent years, people's living standards are getting higher and higher, and life pressure is also increasing, and there are also many problems in eating habits. This is also the direct cause of colon cancer. The aim of this paper was to investigate whether anesthetic drugs could positively affect the proliferation and apoptosis of colon cancer cells. In this paper, the significance of anesthetic drugs is proposed, and an artificial neural network algorithm based on artificial intelligence is proposed. It is well known that artificial neural networks play an important role in medicine. The experimental results of this paper show that the incidence of colon cancer in 2020 will be in the range of 5%-35%, and the incidence of colon cancer in 2021 will be in the range of 7%-30%. While colon cancer rates in 2021 do not appear to be as high as colon cancer rates in 2020, they are generally much higher than colon cancer rates in 2020. It can be seen that as the population ages, the number of colon cancer patients is increasing due to the lack of emphasis on health. This also means that the incidence of colon cancer is getting higher and higher, and traditional drug chemotherapy has been unable to play a good role in inhibiting the proliferation of colon cancer cells. Therefore, this paper investigated the effects of anesthetic drugs on the proliferation and apoptosis of human colon cancer cells.

Astragalus mongholicus Bunge and Curcuma aromatica Salisb. inhibits liver metastasis of colon cancer by regulating EMT via the CXCL8/CXCR2 axis and PI3K/AKT/mTOR signaling pathway

BackgroundOne of the most challenging aspects of colon cancer (CC) prognosis and treatment is liver-tropic metastasis. Astragalus mongholicus Bunge—Curcuma aromatica Salisb. (AC) is a typical medication combination for the therapy of many malignancies. Our previous studies found that AC intervention inhibits liver metastasis of colon cancer (LMCC). Nevertheless, the comprehensive anti-metastasis mechanisms of AC have not been uncovered.MethodsIn bioinformatics analysis, RNA-seq data of CC and LMCC patients were collected from TCGA and GEO databases, and differentially expressed genes (DEGs) were identified. The biological processes and signaling pathways involved in DEGs were enriched by GO and KEGG. The protein–protein interaction (PPI) network of DEGs was established and visualized using the Cytocape software, followed by screening Hub genes in the PPI network using Degree value as the criterion. Subsequently, the expression and survival relevance of Hub gene in COAD patients were verified. In the experimental study, the effects of AC on the inhibition of colon cancer growth and liver metastasis were comprehensively evaluated by cellular and animal models. Finally, based on the results of bioinformatics analysis, the possible mechanisms of AC inhibition of colon cancer EMT and liver metastasis were explored by in vivo and in vitro pharmacological experiments.ResultsIn this study, we obtained 2386 DEGs relevant to LMCC from the COAD (colon adenocarcinoma) and GSE38174 datasets. Results of GO gene function and KEGG signaling pathway enrichment analysis suggested that cellular EMT (Epithelial-mesenchymal transition) biological processes, Cytokine-cytokine receptor interaction and PI3K/Akt signaling pathways might be closely related to LMCC mechanism. We then screened for CXCL8, the core hub gene with the highest centrality within the PPI network of DEGs, and discovered that CXCL8 expression was negatively correlated with the prognosis of COAD patients. In vitro and in vivo experimental evidence presented that AC significantly inhibited colon cancer cell proliferation, migration and invasion ability, and suppressed tumor growth and liver metastasis in colon cancer orthotopic transplantation mice models. Concomitantly, AC significantly reduced CXCL8 expression levels in cell supernatants and serum. Moreover, AC reduced the expression and transcription of genes related to the PI3K/AKT pathway while suppressing the EMT process in colon cancer cells and model mice.ConclusionsIn summary, our research predicted the potential targets and pathways of LMCC, and experimentally demonstrated that AC might inhibit the growth and liver metastasis in colon cancer by regulating EMT via the CXCL8/CXCR2 axis and PI3K/AKT/mTOR signaling pathway, which may facilitate the discovery of mechanisms and new therapeutic strategies for LMCC.

Pt3R5G inhibits colon cancer cell proliferation through inducing ferroptosis by down-regulating SLC7A11

AimsColon cancer (CC) is a prevalent malignancy worldwide and is one of the most easily altered cancers by dietary regulation. Petunidin 3-O-[rhamnopyranosyl-(trans-p-coumaroyl)]-5-O-(β-D-glucopyranoside) (Pt3R5G) isolated and purified from Lycium ruthenicum Murray, which exhibits highly efficient antioxidant activity and specific anticancer effects, is the flavonoids compound. We aimed to study the effect of Pt3R5G on CC cells and elucidate the potential underlying mechanisms. Main methodsCell proliferation was measured by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and colony formation assays. Cell cycle, cell apoptosis and reactive oxygen species (ROS) analysis were performed by flow cytometry. RNA-sequencing was performed to elucidate the potential underlying mechanisms. The lipid peroxidation level of cells was detected by malondialdehyde (MDA) assay. The mitochondrial morphology of cells was inspected using a transmission electron microscope. Additionally, we overexpressed SLC7A11 to perform rescue experiments. In vivo, xenograft mice assay was performed to verify the effect of Pt3R5G on the growth of colon cancer. Key findingsPt3R5G reduced the cell activity by blocking the cell cycle in G0/G1 phase, inducing the apoptosis and ferroptosis in RKO cells. The overexpressed of SLC7A11, a significantly down-regulated expression gene caused by Pt3R5G, rescued the cell proliferation inhibition and ferroptosis process. Furthermore, Pt3R5G inhibited tumor growth in nude mice. Our study suggests that Pt3R5G inhibits RKO cell proliferation through mainly reducing ferroptosis by down-regulated SLC7A11. SignificanceAs a potential therapeutic drug, Pt3R5G showed efficient anticancer activity through a variety of pathways.

Modulation of POPDC1 Expression by Phenothiazine and Trifluoperazine Suppress Colon Cancer Growth and Migration.

The aim of this study was to investigate the effects of CaM antagonist, PTZ, and TFP on cell proliferation and migration of colon cancer cells and its impact on POPDC protein expression. The 50% inhibitory concentration (IC50) of PTZ and TFP in SW1116, SW480, HCT-15, and COLO205 colon cancer cell lines are measured using MTT. Western blot and immunocytochemistry were used to determine the expression of PCNA, cyclin D1 (CD1), and POPDC proteins. Cell migration was observed using a scratch wound-healing assay. Treatment with PTZ and TFP inhibited colon cancer cells growth in a dose-dependent manner. PTZ and TFP significantly inhibited the activation of proliferation markers, PCNA and CD1, and the migration of colon cancer cells. Furthermore, POPDC protein was significantly suppressed in all cell types of colon cancer, particularly in SW480. Finally, the CaM antagonist upregulates the POPDC1 expression in colon cancer cells. These findings suggest that CaM antagonists suppress colon cancer cells proliferation via downregulation of CD1 and PCNA. In addition, POPDC protein could be used as a biomarker in colon cancer, and CaM antagonist could be used to regulate POPDC1 expression. This study suggests that targeting POPDC1 with CaM inhibition could be a potential therapeutic strategy for colon cancer treatment.<br />.

Dominant-Negative Form of SIGIRR: SIGIRRΔE8 Promotes Tumor Growth Through Regulation of Metabolic Pathways

Colorectal carcinoma is the leading cause of cancer-related death. Previously we have shown that tumor suppressor single immunoglobulin interleukin-1-related receptor (SIGIRR) is frequently inactivated in human colorectal cancer by the increased expression of a novel SIGIRR isoform (SIGIRRΔE8). SIGIRRΔE8 showed increased retention in the cytoplasm and loss of complex glycan modification compared to the full-length SIGIRR. Now we found that the arginine residues located in the C-terminus of SIGIRRΔE8 serve as an endoplasmic reticulum retention signal and are required for resident protein ribophorin 1 (RPN1) interaction. In addition, we found that SIGIRRΔE8 exerts a direct impact on cell metabolism through interaction with the adenosine triphosphate synthase in the colorectal cancer cells. SIGIRRΔE8 expression promoted the metabolic shift through upregulation of mammalian target of rapamycin signaling pathway and dysregulation of mitochondrial function to promote survival and proliferation of colon cancer cells in xenograft model.

A natural halogenated fluoride adenosine analog 5'-fluorodeoxy adenosine induced anticolon cancer activity in vivo and in vitro.

Adenosine (ADO) and its analogs have been introduced into the anticancer clinical trials, especial for the ADO derivatives with fluoride. The biosynthesis of fluorinase produces a fluorine-containing ADO analog 5'-fluorodeoxy adenosine (5'-FDA). The toxicity and application of 5'-FDA has not been evaluated, which limits the application of ADO analogs. In order to study its potential mechanism, we carried out the following experiments. In our research, 5'-FDA displayed good antitumor activity in colon cancer cells and two colon cancer models. As a result, 5'-FDA concentration-dependently inhibited the proliferation, migration, and invasion in colon cancer cells through its proapoptosis and cell cycle arrest pathway. Furthermore, 5'-FDA inhibited the growth of colon cancer and its pulmonary metastasis in CT26 inbred mice without affecting their body weight. It was found that 5'-FDA remarkably increased the protein levels of Caspase 3 and cleaved-Caspase 9 and decreased Cyclin A2 and CDK2 via the regulation of p53 signaling pathway, and increased the protein levels of Caspase 8 and cleaved-Caspase 8 which participated in apoptosis pathway. All in all, 5'-FDA displayed excellent therapeutic effects on colon cancer and its pulmonary metastasis. We believed that our study provided a theoretical basis for further preclinical research of 5'-FDA in the treatment of cancer.

DFNA5 inhibits colorectal cancer proliferation by suppressing the mTORC1/2 signaling pathways via upregulation of DEPTOR

ABSTRACT The human deafness, autosomal dominant 5 gene (DFNA5), a newly discovered executor of pyroptosis, has been strongly implicated in the tumorigenesis of several human cancers. However, an understanding of the functional role of DFNA5 in the development and progression of colorectal cancer (CRC) is limited. In this study, we demonstrated that DFNA5 was downregulated in CRC tissues. Ectopic expression of DFNA5 inhibited tumor cell growth in vitro, retarded tumor formation in vivo, and blocked a cell-cycle transition from the G0/G1 to the S phase, whereas a DFNA5 knockdown promoted cell proliferation. Western blotting showed that the levels of cell cycle-related proteins, including cyclin D1, cyclin E, CDK2, and p21, were accordingly altered upon DFNA5 overexpression or DFNA5 knockdown. Mechanistic studies indicated that DFNA5 exerted its tumor suppressor functions by antagonizing mTORC1/2 signaling via upregulation of DEPTOR. In addition, blockage of mTORC1/2 signaling by Torin-1 abolished the accelerative proliferation by DFNA5 knockdown. In conclusion, these results indicated that DFNA5 inhibits the proliferation and tumor formation of colon cancer cells by suppressing mTORC1/2 signaling.

Aloe gel glucomannan induced colon cancer cell death via mitochondrial damage-driven PINK1/Parkin mitophagy pathway

Mitophagy can selectively remove damaged mitochondria, which is critical in regulating mitochondrial homeostasis in diseases, such as cancer. Herein, we found that Aloe gel glucomannan (AGP) significantly inhibited the proliferation of colon cancer cells. RNA-seq analysis revealed that AGP upregulated autophagy, lysosome and mitochondrial fission signal pathways in colon cancer cell line CT26. Notably, AGP induced the accumulation of impaired and reactive oxygen species (ROS)-generating mitochondria, which triggered excessive mitophagy. Interestingly, the mitophagy activator enhanced AGP-induced mitophagy and cytotoxicity, whereas the mitophagy inhibitor reversed the influence of AGP. Furthermore, activation of PINK1/Parkin mitophagy pathway and transcription factor EB (TFEB) signaling was dependent on ROS overproduction. Taken together, these results indicated that AGP induced cytotoxic mitophagy through ROS-related PINK1/Parkin pathway and TFEB activation in CT26 cells. The research would provide theoretical basis for the development of AGP as a promising anticancer agent.