Colon Cancer Stem Cells Research Articles

Veratridine, a plant-derived alkaloid, suppresses the hyperactive Rictor-mTORC2 pathway: a new targeted therapy for primary and metastatic colorectal cancer.

Despite considerable advances to improve colorectal cancer (CRC) survival over the last decade, therapeutic challenges remain due to the rapid metastatic dissemination of primary tumors and screening limitations. Meanwhile, the rise of CRC in younger adults (Early-onset CRC), commonly diagnosed with a metastatic form of the disease, shows the pressing need to develop more effective targeted therapies to decrease the high mortality rates associated with metastatic disease. Hyperactivation of the Rictor-mTORC2-AKT signaling pathway drives key metastatic players in diverse malignant tumors, including early- and late-onset colorectal cancer. Selective mTORC2 inhibitors are becoming a potential treatment strategy for CRC due to the therapeutic limitations of mTORC1 inhibitors. Veratridine (VTD), a lipid-soluble alkaloid extracted from Liliaceae plants, can transcriptionally increase UBXN2A, which induces 26S proteasomal degradation of the Rictor protein, a key member in the mTORC2 complex. Destabilization of Rictor protein by VTD decreases Akt phosphorylation on Ser 473 , which is responsible for metastatic signaling downstream of the mTORC2 pathway in diverse malignant tumors. VTD decreases the population of metastatic colon cancer stem cells and functions as an angiogenesis inhibitor. VTD effectively reduces the spheroid growth rate and restricts cell migration. Live cell migration and invasion assays alongside biomechanical-force-based experiments revealed that VTD suppresses colon cancer cell invasiveness and the ensuing risk of tumor metastasis. A CRC mouse model that mimics the natural stages of human sporadic CRC revealed that VTD treatment significantly decreases tumor growth in a UBXN2A-dependent manner. This study showed a novel mechanistic connection between a ubiquitin-like protein and mTORC2-dependent migration and invasion in CRC tumors. This study revealed the therapeutic benefit of selective inhibition of Rictor in CRC, particularly in tumors with a hyperactive Rictor-mTORC2 signaling pathway. Finally, this study opened a new platform for repurposing VTD, a supplemental anti-hypertension molecule, into an effective targeted therapy in CRC tumors.

The SW480 cell line as a model of resident and migrating colon cancer stem cells

Intra-tumor heterogeneity, i.e., the presence of diverse cell types and subpopulations within tumors, presents a significant obstacle in cancer treatment due to its negative consequences for resistance to therapy and disease recurrence. However, the mechanisms that underlie intra-tumor heterogeneity and result in the plethora of different cancer cells within a single lesion remain poorly understood. Here, we leverage the SW480 cell line as a model system to investigate the molecular and functional diversity of colon cancer cells. Through a combination of fluorescence-activated cell sorting (FACS) analysis and transcriptomic profiling, we identified three distinct subpopulations, namely resident cancer stem cells (rCSCs), migratory CSCs (mCSCs), and high-relapse cells (HRCs). These subpopulations show varying Wnt signaling levels and gene expression profiles mirroring their stem-like and functional properties. Examination of publicly available spatial transcriptomic data confirms the presence of these subpopulations in patient-derived cancers and reveals their distinct spatial distribution relative to the tumor microenvironment.

RGD Density on Tadpole Nanostructures Regulates Cancer Stem Cell Proliferation and Stemness.

Cancer stem cells (CSCs) make up a small population of cancer cells, primarily responsible for tumor initiation, metastasis, and drug resistance. They overexpress Arg-Gly-Asp (RGD) binding integrin receptors that play crucial roles in cell proliferation and stemness through interaction with the extracellular matrix. Here, we showed that monodisperse polymeric tadpole nanoparticles covalently coupled with different RGD densities regulated colon CSC proliferation and stemness in a RGD density-dependent manner. These tadpoles penetrated deeply and evenly into tumor spheroids and specifically entered cells with cancer stem markers CD24 and CD133. Low RGD density tadpoles triggered integrin α5 expression that further activated TGF-β3 and TGF-β2 signaling pathways, confirmed by the increase of pERK and Bcl-2 protein levels. This process is associated with the RGD cluster presentation controlled by the RGD density on the tadpole surface.

MicroRNA-513b-5p inhibits epithelial mesenchymal transition of colon cancer stem cells through IL-6/STAT3 signaling pathway

ObjectiveTo reveal the mechanisms by which miR-513b-5p inhibits metastasis of colon cancer stem cells (CCSCs) through IL-6/STAT3 in HCT116 cells.MethodsSphere formation media and magnetic cell sorting were used to enrich and screen CCSCs. We used a colony formation assay, cell proliferation and viability assays, and a nude mouse transplantation tumor assay to identify CCSCs. ELISA was performed to identify IL-6 in the cell culture medium, and the growth, viability, wound healing, and transwell migration of distinct cell groups were compared to differentiate them. Dual-luciferase reporter assay, RT-PCR, and/or Western Blot analysis were conducted to determine the correlation between them.ResultsCD133+CD44+ HCT116 cells were shown to have higher cloning efficiency, greater proliferation ability and viability, and stronger tumorigenicity. A dual-luciferase reporter assay revealed that miR-513b-5p negatively affected STAT3 expression. RT-PCR and/or Western Blot analysis suggested that miR-513b-5p negatively affected STAT3 and Vimentin, while positively affecting E-cadherin expression. The STAT3 overexpression vector + miR-513b-5p inhibitor cell group had the highest efficiency, greatest proliferation ability and viability, and the highest IL-6 level in the experiments.ConclusionsMir-513b-5p inhibited the epithelial-mesenchymal transition (EMT) of CCSCs through IL-6/STAT3. This potential mechanism may provide a new therapeutic target for colon cancer.

Effect of vitamin E δ-tocotrienol and aspirin on Wnt signaling in human colon cancer stem cells and in adenoma development in APCmin/+ mice.

In this study, we evaluated the effects of vitamin E δ-tocotrienol (DT3) and aspirin on Wnt signaling in human colon cancer stem cells (CCSCs) and in the prevention of adenoma formation in APCmin/+ mice. We found that knockdown of the adenomatous polyposis coli (APC) gene led to subsequent activation of Wnt signaling in colon epithelial cells (NCM460-APCsiRNA) and induction of β-catenin and its downstream target proteins c-MYC, cyclin D1, and survivin. When aspirin and DT3 were combined, cell growth and survival were inhibited and apoptosis was induced in colon epithelial cells and in CCSCs. However, DT3 and/or aspirin had little or no effect on control normal colon epithelial cells (NCM460-NCsiRNA). The induction of apoptosis was directly related to activation of caspase 8 and cleavage of BID to truncated BID. In addition, DT3 and/or aspirin-induced apoptosis was associated with cleaved PARP, elevated levels of cytosolic cytochrome c and BAX, and depletion of anti-apoptotic protein BCl-2 in CCSCs. The combination of aspirin and DT3 inhibited the self-renewal capacity, Wnt/β-catenin receptor activity, and expression of β-catenin and its downstream targets c-MYC, cyclin D1 and survivin in CCSCs. We also found that treatment with DT3 alone or combined with aspirin significantly inhibited intestinal adenoma formation and Wnt/ β-catenin signaling and induced apoptosis, compared to vehicle, in APCmin/+ mice. Our study demonstrated a rationale for further investigation of the combination of DT3 and aspirin for colorectal cancer prevention and therapy.

Chemokine CXCL8 and its receptors as markers of colorectal cancer

BACKGROUND: The chemokine CXCL8 and its receptor are involved in the activation and transport of inflammatory mediators and regulate the proliferation and renewal of cancer stem cells in colon cancer. It is believed that CXC signaling may be associated with poor prognosis in colorectal cancer. AIM: To study the possibilities of using CXCL8-CXCR1/2 pathway indicators as markers in colorectal cancer. MATERIAL AND METHODS: Isolation of ribonucleic acid (RNA) from histological sections of tumors obtained intraoperatively from 59 patients diagnosed with colorectal cancer was carried out using magnetic particles, and quantitative polymerase chain reaction in real time was performed. Calculation of the normalized expression of the CXCL8 and CXCR1 genes relative to the referee gene was done using special software. Statistical data processing was performed using Statistica 3.0, BioStat v. 7.1 programs. Comparisons of characteristics were performed using the Mann–Whitney U test. Cox and Kaplan–Meier criteria were used to analyze overall and disease-free survival. RESULTS: The expression of CXCL8 in intestinal adenocarcinoma cells with low differentiation [Me (Q1–Q3) — 8.770 (1.127–1.114)] was significantly higher than in the groups of moderately and well differentiated tumors (p=0.004 and p=0.012, respectively); and in tumor tissue refractory to chemotherapy, it was significantly higher [4.374 (2.052–7.045)] compared to resistant [2.200 (1.388–5.037); p=0.008] and sensitive [1.624 (0.739–2.586); p=0.042]. The level of CXCR1 messenger RNA in tumor tissue was increased in the presence of BRAF mutation [3.645 (0.801–1.090); p=0.009] and low tumor differentiation [6.965 (3.938–12.225); p=0.002], as well as in tumor tissue refractory to FOLFOX/XELOX chemotherapy [46.224 (27.580–83.570); p=0.0009]. CONCLUSION: Expression of components of the CXCL8-CXCR1/2 signaling pathway in tumor tissue may be a marker of sensitivity to FOLFOX/XELOX chemotherapy in colorectal cancer.

Impact of the thyroid hormone T3 and its nuclear receptor TRα1 on colon cancer stem cell phenotypes and response to chemotherapies

Colorectal cancers (CRCs) are highly heterogeneous and show a hierarchical organization, with cancer stem cells (CSCs) responsible for tumor development, maintenance, and drug resistance. Our previous studies showed the importance of thyroid hormone-dependent signaling on intestinal tumor development and progression through action on stem cells. These results have a translational value, given that the thyroid hormone nuclear receptor TRα1 is upregulated in human CRCs, including in the molecular subtypes associated with CSC features. We used an established spheroid model generated from the human colon adenocarcinoma cell line Caco2 to study the effects of T3 and TRα1 on spheroid formation, growth, and response to conventional chemotherapies. Our results show that T3 treatment and/or increased TRα1 expression in spheroids impaired the response to FOLFIRI and conferred a survival advantage. This was achieved by stimulating drug detoxification pathways and increasing ALDH1A1-expressing cells, including CSCs, within spheroids. These results suggest that clinical evaluation of the thyroid axis and assessing TRα1 levels in CRCs could help to select optimal therapeutic regimens for patients with CRC.Proposed mechanism of action of T3/TRα1 in colon cancer spheroids. In the control condition, TRα1 participates in maintaining homeostatic cell conditions. The presence of T3 in the culture medium activates TRα1 action on target genes, including the drug efflux pumps ABCG2 and ABCB1. In the case of chemotherapy FOLFIRI, the increased expression of ABC transcripts and proteins induced by T3 treatment is responsible for the augmented efflux of 5-FU and Irinotecan from the cancer cells. Taken together, these mechanisms contribute to the decreased efficacy of the chemotherapy and allow cells to escape the treatment. Created with BioRender.com.

Abstract 1566: Cancer metastasis and stemness: The metastasis-inducer MACC1 regulates LGR5 to promote cancer stem cell-like properties in colorectal cancer

Abstract Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. The high mortality is directly associated with metastatic disease which is thought to be initiated by colon cancer stem cells according to cancer stem cell (CSC) model. Consequently, early identification of those patients who are at high risk for metastasis is crucial for improved treatment and patient outcome. Metastasis-associated in colon cancer 1 (MACC1) is a novel prognostic biomarker for tumor progression and metastasis formation independent of tumor stage. We previously showed an involvement of MACC1 in cancer stemness in the mouse intestine of our transgenic mouse models. However, the expression of MACC1 in human CSCs and possible implications remain elusive. Here, we explored the molecular mechanisms by which MACC1 regulates stemness and CSC-associated invasive phenotype based on patient-derived 3D cell culture models (PD3D), patient-derived xenografts (PDX) and human CRC cell lines. We showed that CD44-enriched CSCs from PD3D models express significantly higher levels of MACC1 and display higher tumorigenicity in immunocompromised mice. Similarly, RNA sequencing performed on PD3D and PDX models demonstrated significantly increased MACC1 expression in ALDH1(+) CSCs, highlighting its involvement in cancer stemness. We further showed the correlation of MACC1 with CSC markers CD44, NANOG and LGR5 in PD3D models as well as established cell lines. Additionally, MACC1 increased stem cell gene expression, clonogenicity and sphere formation. Strikingly, we showed that MACC1 binds as a transcription factor to the LGR5 gene promoter uncovering the long-known CSC marker LGR5 as novel essential signaling mediator used by MACC1 to induce CSC-like properties in human CRC patients. Our in vitro findings were further substantiated by significant positive correlation of MACC1 and LGR5 in CRC cell lines as well as CRC patient tumors. Taken together, this study indicates that the metastasis-inducer MACC1 act as a cancer stem cell-associated marker. Interventional approaches targeting MACC1 would potentially improve further targeted therapies for colorectal cancer patients to eradicate CSCs, prevent cancer recurrence and distant metastasis formation. Citation Format: Müge Erdem, Kyung Hwan Lee, Markus Hardt, Joseph Regan, Dennis Kobelt, Wolfgang Walther, Christian Regenbrecht, Ulrike S. Stein. Cancer metastasis and stemness: The metastasis-inducer MACC1 regulates LGR5 to promote cancer stem cell-like properties in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1566.

Abstract 5599: Role of HOX gene expression in differentiation of colon cancer stem cells

Abstract HOX genes encode a highly conserved set of transcription factors critical for stem cell (SC) function and embryonic development. Several HOX genes have also been implicated in a myriad of cancers, including colorectal cancer (CRC). However, how HOX genes play a role in SC regulation and contributes to cancer development is unclear. HOX expression is regulated by WNT, FGF, and retinoic acid (RA) signaling - pathways which also become dysregulated in cancer. Goal: To determine how regulation of HOX genes specifies differentiation of colonic SCs into specialized cell lineages and how dysregulation of HOX genes contributes to CRC development. Hypotheses: i) Each of the different cell types within human colonic epithelium has a distinct HOX gene expression signature; ii) All-trans retinoic acid (ATRA) induced differentiation of CRC cells changes HOX expression that correlates with specific HOX expression signatures in normal colon and CRC cells. Results: Immunostaining shows that specific HOX proteins (e.g., HOXA9 & HOXC9) are selectively expressed in ALDH-positive SCs and expression of these HOX genes is increased in CRC tissues compared to normal epithelium. Bioinformatics analysis predicted that these HOX genes (plus HOXA4, HOXA10, HOXC8) are regulated by RA signaling. Accordingly, we studied how ATRA influences HOX expression in CRC cells (HT29 & SW480). We found ATRA treatment: 1) Decreases proliferation and increases neuroendocrine cell (NEC) differentiation; and 2). Leads to specific changes in HOX gene expression patterns. Using NanoString profiling, we also discovered that LGR5+ SCs, ALDH+ SCs and GLP2R+ NECs have unique HOX signatures. By defining how these HOX gene expression changes in response to ATRA treatment in comparison to the HOX gene signatures of different colonic cell lineages will help us understand the role that HOX genes play in SC differentiation and how dysregulation of HOX gene expression contributes to CRC development. Citation Format: Brian T. Osmond, Caroline O. Facey, Lynn O. Opdenaker, Chi Zhang, Bruce M. Boman. Role of HOX gene expression in differentiation of colon cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5599.

A Two-Stage Transferred Cold Atmospheric Plasma as a Unique Therapeutic Strategy for Targeting Colon Cancer Stem Cells.

The study examines the induction of apoptosis in colon cancer stem cells (CCSCs) within a 3D culture setting, employing an innovative cold atmospheric plasma (CAP) transmission method known as two-stage transferred cold atmospheric plasma (TS-TCAP). TS-TCAP is a partially or fully ionized non-thermal gaseous mixture that comprises photons, charged and neutral particles, and free radicals, which has gained traction in biomedical applications such as cancer therapy. TS-TCAP impacts CCSCs via a continuous, two-step transport process, facilitating the efficient delivery of reactive oxygen and nitrogen species (RONS). The key cellular factors of CCSCs impacted by TS-TCAP treatment, encompassing the secretion and expression levels of IL-6 and IL-8, apoptotic cell count, and expression of BAX, BCL-2, and KI-67 proteins, were evaluated using qrt-ELISA, Annexin V, and qrt-PCR procedures, respectively. The outcomes of CCSCs treatment with TS-TCAP reveal a notable rise in the number of apoptotic cells (P<0.0001), diminished secretion, and gene expression of IL-6 and IL-8 (P<0.0001), accompanied by favorable alterations in BCL-2 and BAX gene expression (P<0.0001). Additionally, a notable decrease in KI-67 expression was observed, correlating with a reduction in CCSCs proliferation (P<0.0001). As well, this study underscores the anti-cancer potential of TS-TCAP, showcasing its efficacy in reducing CCSCs survival rates. However, further pre-clinical and clinical trials are necessary to evaluate CAP's efficacy, safety, and potential synergistic effects with other therapies thoroughly. Overall, TS-TCAP presents a promising alternative for CCSCs treatment, pending further investigation and refinement.

Xiao Tan San Jie Fang Hampers the Growth of Colon Cancer Stem Cells through the Wnt/β-catenin Signaling Pathway

Abstract Objective: The purpose of this research was to examine the potential anticancer properties of Xiao Tan San Jie Fang (XTSJF) and its potential mechanism of action against colorectal cancer. Materials and Methods: HCT116 cells were induced into HCT116 spheres in DMEM/F12 medium by treatment with epidermal growth factor + fibroblast growth factor + leukemia inhibitory factor + B27. The proliferation ability and stemness of HCT116 spheres was examined. Various concentrations of XTSJF were used to treat HCT116 spheres to observe the impact on proliferation, apoptosis, and expression of stem cell markers. Next, Wnt/β-catenin pathway-related factor proteins were detected. Results: The findings revealed that XTSJF suppressed cell growth and induced cell death in HCT116 cells in a dosage-dependent manner. Similarly, XTSJF promotes apoptosis, inhibits cell proliferation, prolongs survival, and maintains the expression of stem cells through the Wnt/-catenin/TCF4 axis. XTSJF also inhibits AKT activity and subsequently activates glycogen synthesis kinase-3β expression, inhibiting Wnt/beta-catenin pathway activity and downstream target gene transcript expression. The Wnt/β-catenin signaling pathway is inhibited by the XTSJF, leading to the suppression of colon cancer stem cell proliferation. Conclusion: Xiaotan Sanjie Prescription inhibited colon cancer stem cell growth through Wnt/β-catenin signaling pathway.

Ethyl-acetate extract of Spatholobi Caulis blocked the pro-metastatic support from the hemato-microenvironment of colon cancer by specific disruption of tumor-platelet adhesion

BackgroundWithin the pro-metastatic hemato-microenvironment, interaction between platelets and tumor cells provides essential support for tumor cells by inducing Epithelial-Mesenchymal Transition (EMT), which greatly increases the stemness of colon cancer cells. Pharmacologically, although platelet deactivation has proved to be benefit against metastasis, its wide application is severely restricted due to the bleeding risk. Spatholobi Caulis, a traditional Chinese herb with circulatory promotion and blood stasis removal activity, has been proved to be clinically effective in malignant medication, leaving its mechanistic relevance to tumor-platelet interaction largely unknown. MethodsFirstly, MC38-Luc cells were injected into tail-vein in C57BL/6 mice to establish hematogenous metastasis model and the anti-metastasis effects of SEA were evaluated by using a small-animal imaging system. Then, we evaluated the anti-tumor-platelet interaction efficacy of SEA using a tumor-specific induced platelet aggregation model. Platelet aggregation was specifically induced by tumor cells in vitro. Furthermore, to clarify the anti-metastatic effects of SEA is mainly attributed to its blockage on tumor-platelet interaction, after co-culture with tumor cells and platelets (with or without SEA), MC38-Luc cells were injected into the tail-vein and finally count the total of photons quantitatively. Besides, to clarify the blocking pattern of SEA within the tumor-platelet complex, the dependence of SEA on different fractions from activated platelets was tested. Lastly, molecular docking screening were performed to screen potential effective compounds and we used β-catenin blockers to verify the pathways involved in SEA blocking tumor-platelet interaction. ResultsOur study showed that SEA was effective in blocking tumor-platelet specific interaction: (1) Through CCK-8 and LDH assays, SEA showed no cytotoxic effects on tumor cells and platelets. On this basis, by the tail vein injection model, the photon counts in the SEA group was significantly lower than model group, indicating that SEA effectively reduced metastasis. (2) In the "tumor-platelet" co-culture model, SEA effectively inhibited the progression of EMT and cancer stemness signatures of MC38 cells in the model group. (3) In mechanism study, by using the specific inhibitors for galectin-3 (GB1107) andWNT (IWR) respectively, we proved that SEA inhibits the activation of the galectin-3-mediated β-catenin activation. ConclusionBy highlighting the pro-metastatic effects of galectin-3-mediated tumor-platelet adhesion, our study provided indicative evidence for Spatholobi Caulis as the representative candidate for anti-metastatic therapy.

Preclinical Repurposing of Sitagliptin as a Drug Candidate for Colorectal Cancer by Targeting CD24/CTNNB1/SOX4-Centered Signaling Hub.

Despite significant advances in treatment modalities, colorectal cancer (CRC) remains a poorly understood and highly lethal malignancy worldwide. Cancer stem cells (CSCs) and the tumor microenvironment (TME) have been shown to play critical roles in initiating and promoting CRC progression, metastasis, and treatment resistance. Therefore, a better understanding of the underlying mechanisms contributing to the generation and maintenance of CSCs is crucial to developing CSC-specific therapeutics and improving the current standard of care for CRC patients. To this end, we used a bioinformatics approach to identify increased CD24/SOX4 expression in CRC samples associated with poor prognosis. We also discovered a novel population of tumor-infiltrating CD24+ cancer-associated fibroblasts (CAFs), suggesting that the CD24/SOX4-centered signaling hub could be a potential therapeutic target. Pathway networking analysis revealed a connection between the CD24/SOX4-centered signaling, β-catenin, and DPP4. Emerging evidence indicates that DPP4 plays a role in CRC initiation and progression, implicating its involvement in generating CSCs. Based on these bioinformatics data, we investigated whether sitagliptin, a DPP4 inhibitor and diabetic drug, could be repurposed to inhibit colon CSCs. Using a molecular docking approach, we demonstrated that sitagliptin targeted CD24/SOX4-centered signaling molecules with high affinity. In vitro experimental data showed that sitagliptin treatment suppressed CRC tumorigenic properties and worked in synergy with 5FU and this study thus provided preclinical evidence to support the alternative use of sitagliptin for treating CRC.

Identification of small molecule inhibitors against doublecortin-like kinase 1 for targeting colon cancer stem cells

Identification of small molecule inhibitors against doublecortin-like kinase 1 for targeting colon cancer stem cells

Silencing LY6D Expression Inhibits Colon Cancer in Xenograft Mice and Regulates Colon Cancer Stem Cells' Proliferation, Stemness, Invasion, and Apoptosis via the MAPK Pathway.

This study explored the role of lymphocyte antigen 6 family member D (LY6D) in colon cancer stem cells' (CCSCs) proliferation and invasion. LY6D was knocked down using siRNA, and the down-regulation of LY6D was verified using Western blotting. After LY6D knockdown, CCSCs' proliferation, stemness, and invasion were suppressed, whereas apoptosis was increased. Gene Ontology (GO) enrichment analysis revealed that the differentially expressed genes (DEGs) between siLY6D and the negative control groups were significantly enriched in the cell-substrate adherens junction, focal adhesion, and cell-substrate junction terms. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the DEGs were significantly enriched in the MAPK pathway. In addition, Western blotting results showed that pBRAF and pERK1/2, cascade kinases of the MAPK pathway, were significantly down-regulated after LY6D knockdown. In addition, nude mice xenograft experiments showed that the siLY6D treatment decreased tumor sizes and weights and improved tumor-bearing mice survival rates compared with the control group. In conclusion, these findings indicate that LY6D, which is highly expressed in CCSCs, is a key factor involved in tumor growth and development and might be a potential cancer marker and therapeutic target for colon cancer.

Can the phenolic compounds of Manuka honey chemosensitize colon cancer stem cells? A deep insight into the effect on chemoresistance and self-renewal.

Manuka honey, which is rich in pinocembrin, quercetin, naringenin, salicylic, p-coumaric, ferulic, syringic and 3,4-dihydroxybenzoic acids, has been shown to have pleiotropic effects against colon cancer cells. In this study, potential chemosensitizing effects of Manuka honey against 5-Fluorouracil were investigated in colonspheres enriched with cancer stem cells (CSCs), which are responsible for chemoresistance. Results showed that 5-Fluorouracil increased when it was combined with Manuka honey by downregulating the gene expression of both ATP-binding cassette sub-family G member 2, an efflux pump and thymidylate synthase, the main target of 5-Fluorouracil which regulates the ex novo DNA synthesis. Manuka honey was associated with decreased self-renewal ability by CSCs, regulating expression of several genes in Wnt/β-catenin, Hedgehog and Notch pathways. This preliminary study opens new areas of research into the effects of natural compounds in combination with pharmaceuticals and, potentially, increase efficacy or reduce adverse effects.

Retraction Note: NF-κB maintains the stemness of colon cancer cells by downregulating miR-195- 5p/497–5p and upregulating MCM2

Retraction Note: NF-κB maintains the stemness of colon cancer cells by downregulating miR-195- 5p/497–5p and upregulating MCM2

Boron-Doped Carbon Nanodots as a Theranostic Agent for Colon Cancer Stem Cells.

Carbon nanodots have drawn a great deal of attention due to their green and expedient opportunities in biological and chemical sciences. Their high fluorescence capabilities and low toxicity for living cells and tissues make them excellent imaging agents. In addition, they have a fluorimetric response against inorganic and organic species. Boron-doped carbon nanodots (B-CDs) with high fluorescence yield were produced from phenylboronic acid and glutamine as boron and carbon sources, respectively, by a hydrothermal method. First, the effects of the temperature on their fluorescence yield and the structural characteristics of B-CDs were investigated. Second, their cytotoxicity and cell death and proliferation behaviors were examined. The cytotoxicity was evaluated by the MTT assay. The cellular properties were evaluated with the distribution of caspase 3, Ki67, lamin B1, P16, and cytochrome c after the indirect immunoperoxidase technique. After the MTT assay, 1:1 dilution of all applicants for 24 h was used in the study. After immunohistochemical analyses, the application of B-CDs synthesized at 230 °C did not change control cell (Vero) proliferation, and also apoptosis was not triggered. Colo 320 CD133+ and CD133- cell-triggered apoptosis and cellular senescence were found to be synthesis temperature dependent. In addition, Colo 320 CD133- cells were affected relatively more than CD133+ cells from B-CDs. While B-CDs did not affect the control cells, the colon cancer stem cells (Colo 320 CD133+) were affected in a time-dependent manner. Therefore, the use of the synthesized B-CD product may be an alternative method for controlling or eliminating cancer stem cells in the tumor tissue.

Inducing Cytotoxicity in Colon Cancer Cells and Suppressing Cancer Stem Cells by Dolasetron and Ketoprofen through Inhibition of RNA Binding Protein PUM1.

Clinical trials of new drugs often face a high failure rate of approximately 45 percent due to safety and toxicity concerns. Repurposing drugs with well-established safety profiles becomes crucial in addressing this challenge. Colon cancer ranks as the third most prevalent cancer and the second leading cause of cancer related mortality worldwide. This study focuses on the RNA-binding protein pumilio1 (PUM1), a member of the PUF family involved in post-transcriptional gene expression regulation. By utilizing molecular docking techniques and FDA-approved drugs, potential inhibitors against PUM1 were identified. Notably, dolasetron and ketoprofen demonstrated promising results, exhibiting strong binding affinity, hydrophobic interactions, and favorable chemical reactivity according to Conceptual-DFT calculations. Both compounds effectively reduced cell viability, with IC50 values of 150 µM and 175 µM, respectively and shows long term inhibitory effects as seen by reduced in number of colonies. Moreover, they exhibited inhibitory effects on colon cancer stem cells, as indicated by reduced colonospheroid size and numbers. Apoptosis is induced by these compounds and has triggered activation of executioner caspase 3/7 in HCT116 cells which is evident through a caspase 3/7 assay and AO/EB staining, while the non-toxic effect of these compounds was evident from viability against non-cancerous cell line and hemolysis assay. Additionally, the treatment group showed a significant decrease in PUM1 and cancer stem cell markers expression compared to the control group. In conclusion, this study highlights the potential of targeting PUM1 as a novel approach to colon cancer treatment. Dolasetron and ketoprofen demonstrate promise as effective anti-cancer and anti-cancer stem cell drugs, inducing apoptosis in colon cancer cells through inhibition of PUM1.

Isoliensinine augments the therapeutic potential of paclitaxel in multidrug-resistant colon cancer stem cells and induced mitochondria-mediated cell death.

Previously we have reported the isoliensinine (ISO) potentates the therapeutic potential of cisplatin in cisplatin resistant colorectal cancer stem cells. The present study evaluates the chemo-sensitizing potential of the combinatorial regimen of ISO and Paclitaxcel (PTX) on multidrug-resistant (MDR)-HCT-15 cells to reduce the dose requirement of both ISO and PTX. The results of the present study suggest that treatment with the combinatorial regimen of ISO and PTX enhanced the cytotoxic effect with resultant increase in apoptosis in MDR-HCT-15 cells as evident from the altered cellular morphology, G2/M cell cycle arrest, propidium iodideuptake, Annexin V, increased intracellular Ca2+ accumulation, decreased mitochondrial membrane potential, diminished ATP production, PARP-1 cleavage, altered expression of ERK1/2, and apoptotic proteins. Treatment with combinatorial regimen of ISO and PTX also modulated the expression of the transcription factors SOX2, OCT4 which determine the stemness of cancer cells. Thus, results of the present study suggest that ISO and PTX combination regimen induces apoptosis in MDR-HCT-15 in a synergistic manner.