In vivo and in vitro studies on the role of regulating Smac expression in the occurrence and development of colon cancer.

We aimed to explore the role of regulating Smac expression levels in the occurrence and development of colon cancer through in vitro and in vivo experiments. Colon cancer cells HT-29 were cultured and transfected into different groups. qRT-PCR was used to detect the expression level of Smac in cells; Flow cytometry was used to detect the apoptotic ability of each group of cells; Western blot was used to detect the protein expression of Smac and apoptosis-related factors Survivin and Caspase-3; The nude mouse tumorigenesis experiment was conducted to detect the regulatory effect of regulating Smac expression levels on the growth of colon cancer transplanted tumors in vivo. In comparison to the FHC group, the HT-29 group exhibited a decrease in Smac expression. The si-Smac group, when compared with the si-NC group, showed significant reductions in Smac mRNA and protein levels, weaker cell apoptosis, increased Survivin, and decreased Caspase-3 expression. Contrarily, the oe-Smac group, against the oe-NC group, displayed increased Smac mRNA and protein levels, enhanced apoptosis, reduced Survivin, and elevated Caspase-3 expression. In nude mice tumor transplantation experiments, the LV-sh-Smac group, as opposed to the LV-sh-NC group, had tumors with greater volume and weight, reduced Smac and Caspase-3, and increased Survivin expression. In contrast, the LV-oe-Smac group, compared with the LV-oe-NC group, showed tumors with decreased volume and mass, increased expressions of Smac and Caspase-3, and decreased Survivin. Smac is lowly expressed in colon cancer. Upregulation of Smac expression can inhibit the occurrence and development of colon cancer, possibly by inhibiting Survivin expression and promoting Caspase-3 expression, thereby enhancing the pro-apoptotic function.

Selective but not pan-CDK inhibition abrogates 5-FU-driven tissue factor upregulation in colon cancer.

Thromboembolic events are complications in cancer patients and hypercoagulability has been linked to the tissue factor (TF) pathway, making this an attractive target. Here, we investigated the effects of chemotherapeutics and CDK inhibitors (CDKI) abemaciclib/palbociclib (CDK4/6), THZ-1 (CDK7/12/13), and dinaciclib (CDK1/2/5/9) alone and in combination regimens on TF abundance and coagulation. The human colorectal cancer (CRC) cell line HROC173 was treated with 5-FU or gemcitabine to stimulate TF expression. TF+ cells were sorted, recultured, and re-analyzed. The effect of treatment alone or in combination was assessed by functional assays. Low-dose chemotherapy induced a hypercoagulable state and significantly upregulated TF, even after reculture without treatment. Cells exhibited characteristics of epithelial-mesenchymal transition, including high expression of vimentin and mucin. Dinaciclib and THZ-1 also upregulated TF, while abemaciclib and palbociclib downregulated it. Similar results were observed in coagulation assays. The same anticoagulant activity of abemaciclib was seen after incubation with peripheral immune cells from healthy donors and CRC patients. Abemaciclib reversed 5-FU-induced TF upregulation and prolonged clotting times in second-line treatment. Effects were independent of cytotoxicity, senescence, and p27kip1 induction. TF-antibody blocking experiments confirmed the importance of TF in plasma coagulation, with Factor XII playing a minor role. Short-term abemaciclib counteracts 5-FU-induced hypercoagulation and eventually even prevents thromboembolic events.

Identification of extracellular matrix-related biomarkers in colon adenocarcinoma by bioinformatics and experimental validation.

Backgrounds: Extracellular matrix (ECM) is an important component of tumor microenvironment, and its abnormal expression promotes tumor formation, progression and metastasis. Methods: Weighted gene co-expression network analysis (WGCNA) was used to identify ECM-related hub genes based on The Cancer Genome Atlas (TCGA) colon adenocarcinoma (COAD) data. COAD clinical samples were used to verify the expression of potential biomarkers in tumor tissues, and siRNA was used to explore the role of potential biomarkers in cell proliferation and epithelial-mesenchymal transition (EMT). Results: Three potential biomarkers (LEP, NGF and PCOLCE2) related to prognosis of COAD patients were identified and used to construct ERGPI. Immunohistochemical analysis of clinical samples showed that the three potential biomarkers were highly expressed in tumor tissues of COAD patients. Knockdown of LEP, NGF or PCOLCE2 inhibited COAD cell proliferation and EMT. Dictamnine inhibited tumor cell growth by binding to these three potential biomarkers based on molecular docking and transplanted tumor model. Conclusion: The three biomarkers can provide new ideas for the diagnosis and targeted therapy of COAD patients.

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 .

Tumor derived exosomal ENTPD2 impair CD8+ T cell function in colon cancer through ATP-adenosine metabolism reprogramming.

BACKGROUND: Extracellular ATP-AMP-adenosine metabolism plays a pivotal role in modulating tumor immune responses. Previous studies have shown that the conversion of ATP to AMP is primarily catalysed by Ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1/CD39), a widely studied ATPase, which is expressed in tumor-associated immune cells. However, the function of ATPases derived from tumor cells themselves remains poorly understood. The purpose of this study was to investigate the role of colon cancer cell-derived ATPases in the development and progression of colon cancer. METHODS: Bioinformatic and tissue microarray analyses were performed to investigate the expression of ATPase family members in colon cancer. An ATP hydrolysis assay, high-performance liquid chromatography (HPLC), and CCK8 and colony formation assays were used to determine the effects of ENTPD2 on the biological functions of colon cancer cells. Flow cytometric and RNA-seq analyses were used to explore the function of CD8+ T cells. Immunoelectron microscopy and western blotting were used to evaluate the expression of ENTPD2 in exosomes. Double-labelling immunofluorescence and western blotting were used to examine the expression of ENTPD2 in serum exosomes and colon cancer tissues. RESULTS: We found that ENTPD2, rather than the well-known ATPase CD39, is highly expressed in cancer cells and is significantly positively associated with poor patient prognosis in patients with colon cancer. The overexpression of ENTPD2 in cancer cells augmented tumor progression in immunocompetent mice by inhibiting the function of CD8+ T cells. Moreover, ENTPD2 is localized primarily within exosomes. On the one hand, exosomal ENTPD2 reduces extracellular ATP levels, thereby inhibiting P2X7R-mediated NFATc1 nuclear transcription; on the other hand, it facilitates the increased conversion of ATP to adenosine, hence promoting adenosine-A2AR pathway activity. In patients with colon cancer, the serum level of exosomal ENTPD2 is positively associated with advanced TNM stage and high tumor invasion depth. Moreover, the level of ENTPD2 in the serum exosomes of colon cancer patients is positively correlated with the ENTPD2 expression level in paired colon cancer tissues, and the ENTPD2 level in both serum exosomes and tissues is significantly negatively correlated with the ENTPD2 expression level in tumor-infiltrating CD8+ T cells. CONCLUSION: Our study suggests that exosomal ENTPD2, originated from colon cancer cells, contributes to the immunosuppressive microenvironment by promoting ATP-adenosine metabolism. These findings highlight the importance of exosome-derived hydrolytic enzymes as independent entities in shaping the tumor immune microenvironment.

Caffeic Acid Enhances Anticancer Drug-induced Apoptosis in Acid-adapted HCT116 Colon Cancer Cells.

BACKGROUND/AIM: Apoptosis resistance in cancer cells adapted to acidic microenvironments poses a challenge for effective treatment. This study investigated the potential use of caffeic acid as an adjunct therapy to overcome drug resistance in colorectal cancer cells under acidic conditions. MATERIALS AND METHODS: Long-term exposure to low-pH conditions induced resistance in HCT116 colorectal cancer cells. The effects of caffeic acid on proliferation, clonogenicity, and apoptosis induction were assessed alone and in combination with oxaliplatin and 5-Fluorouracil. The signaling pathways involved in drug resistance were examined by assessing the activities of PI3K/Akt and ERK1/2. RESULTS: Caffeic acid inhibited the proliferation and clonogenicity of acid-adapted cancer cells, and enhanced apoptosis when combined with anticancer drugs. Mechanistically, caffeic acid attenuated the hyperactivation of the PI3K/Akt and ERK1/2 signaling pathways associated with drug resistance. CONCLUSION: Caffeic acid is a promising therapeutic agent for targeting resistant cancer cells in acidic microenvironments. Its ability to inhibit proliferation, sensitize cells to apoptosis, and modulate signaling pathways highlights its potential for overcoming drug resistance in cancer therapy.

ARHGAP4 as a Prognostic Biomarker for Colon Liver Metastases After Surgical Resection.

BACKGROUND/AIM: To select and stratify patients for optimal treatment plans is challenging. Identification of cancer-related biomarkers that serve as predictors for prognosis and treatment response is essential to better predict treatment outcome and find future targets for therapy. Previous data has suggested ARHGAP4 as a relevant biomarker in colorectal cancer (CRC). The purpose of this study was to assess how ARHGAP4 expression affected patients undergoing surgery for colon liver metastasis (CLM) in terms of overall survival (OS). PATIENTS AND METHODS: A total of 251 patients undergoing resection of CLM from 2006 to 2017 were included. Corresponding resected tumor specimens were examined for ARHGAP4 expression levels by immunohistochemistry (IHC). The correlation between ARHGAP4 expression and postoperative survival was analyzed. RESULTS: High expression levels of ARHGAP4 were seen in 60% of patients. High expression levels of ARHGAP4 were correlated with adverse prognosis after hepatectomy due to CLM. Survival data generated using Cox proportional hazard model showed a statistically significant difference between high and low ARHGAP4 expression groups by univariate (HR=1.5, 95% CI=1.1-2.2) and multivariate (HR=1.5, 95% CI=1.0-2.1) analysis. In multivariate Cox regression, high ARHGAP4 expression, preoperative CEA levels and presence of vascular invasion by pathological examinations were independent predictive factors of overall survival. CONCLUSION: ARHGAP4 is a novel prognostic biomarker after resection of CLM.

RRM2 Is a CTNNB1 Transport Regulator Promoting Colon Cancer Progression.

BACKGROUND/AIM: The cytoplasmic retention and stabilization of CTNNB1 (ß-catenin) in response to Wnt is well documented in playing a role in tumor growth. Here, through the utilization of a multiplex siRNA library screening strategy, we investigated the modulation of CTNNB1 function in tumor cell progression by ribonucleoside-diphosphate reductase subunit M2 (RRM2). MATERIALS AND METHODS: We conducted a multiplex siRNA screening assay to identify targets involved in CTNNB1 nuclear translocation. In order to examine the effect of inhibition of RRM2, selected from the siRNA screening results, we performed RRM2 knockdown and assayed for colon cancer cell viability, sphere formation assay, and invasion assay. The interaction of RRM2 with CTNNB1 and its impact on oncogenesis was examined using immunoprecipitation, immunoblotting, immunocytochemistry, and RT-qPCR. RESULTS: After a series of screening and filtration steps, we identified 26 genes that were potentially involved in CTNNB1 nuclear translocation. All candidate genes were validated in various cell lines. The results revealed that siRNA-mediated knockdown of RRM2 reduces the nuclear translocation of CTNNB1. This reduction was accompanied by a decrease in cell count, resulting in a suppressive effect on tumor cell growth. CONCLUSION: High throughput siRNA screening is an attractive strategy for identifying gene functions in cancers and the interaction between RRM2 and CTNNB1 is an attractive drug target for regulating RRM2-CTNNB1-related pathways in cancers.

Blue light irradiation inhibits the M2 polarization of the cancer-associated macrophages in colon cancer.

Recent studies have shown that blue light-emitting diode (LED) light has anti-tumor effects, suggesting the possibility of using visible light in cancer therapy. However, the effects of blue light irradiation on cells in the tumor microenvironment, including tumor-associated macrophages (TAMs), are unknown. Here, THP-1 cells were cultured in the conditioned medium (CM) of HCT-116 cells to prepare TAMs. TAMs were divided into LED-irradiated and control groups. Then, the effects of blue LED irradiation on TAM activation were examined. Expression levels of M2 macrophage markers CD163 and CD206 expression were significantly decreased in LED-irradiated TAMs compared with the control group. While control TAM-CM could induce HCT-116 cell migration, these effects were not observed in cells cultured in TAM-CM with LED irradiation. Vascular endothelial growth factor (VEGF) secretion was significantly suppressed in LED-exposed TAMs. PD-L1 expression was upregulated in HCT-116 cells cultured with TAM-CM but attenuated in cells cultured with LED-irradiated TAM-CM. In an in vivo model, protein expression levels of F4/80 and CD163, which are TAM markers, were reduced in the LED-exposed group. These results indicate that blue LED light may have an inhibitory effect on TAMs, as well as anti-tumor effects on colon cancer cells.

Na,K-ATPase activity promotes macropinocytosis in colon cancer via Wnt signaling.

Recent research has shown that membrane trafficking plays an important role in canonical Wnt signaling through sequestration of the ß-catenin destruction complex inside multivesicular bodies (MVBs) and lysosomes. In this study, we introduce Ouabain, an inhibitor of the Na,K-ATPase pump that establishes electric potentials across membranes, as a potent inhibitor of Wnt signaling. We find that Na,K-ATPase levels are elevated in advanced colon carcinoma, that this enzyme is elevated in cancer cells with constitutively activated Wnt pathway and is activated by GSK3 inhibitors that increase macropinocytosis. Ouabain blocks macropinocytosis, which is an essential step in Wnt signaling, probably explaining the strong effects of Ouabain on this pathway. In Xenopus embryos, brief Ouabain treatment at the 32-cell stage, critical for the earliest Wnt signal in development-inhibited brains, could be reversed by treatment with Lithium chloride, a Wnt mimic. Inhibiting membrane trafficking may provide a way of targeting Wnt-driven cancers.

The dysadherin/FAK axis promotes individual cell migration in colon cancer.

Dysregulation of cancer cell motility is a key driver of invasion and metastasis. High dysadherin expression in cancer cells is correlated with invasion and metastasis. Here, we found the molecular mechanism by which dysadherin regulates the migration and invasion of colon cancer (CC). Comprehensive analysis using single-cell RNA sequencing data from CC patients revealed that high dysadherin expression in cells is linked to cell migration-related gene signatures. We confirmed that the deletion of dysadherin in tumor cells hindered local invasion and distant migration using in vivo tumor models. In this context, by performing cell morphological analysis, we found that aberrant cell migration resulted from impaired actin dynamics, focal adhesion turnover and protrusive structure formation upon dysadherin expression. Mechanistically, the activation of focal adhesion kinase (FAK) was observed in dysadherin-enriched cells. The dysadherin/FAK axis enhanced cell migration and invasion by activating the FAK downstream cascade, which includes the Rho family of small GTPases. Overall, this study illuminates the role of dysadherin in modulating cancer cell migration by forcing actin dynamics and protrusive structure formation via FAK signaling, indicating that targeting dysadherin may be a potential therapeutic strategy for CC patients.

EMMPRIN promotes spheroid organization and metastatic formation: comparison between monolayers and spheroids of CT26 colon carcinoma cells.

Background: In vitro studies often use two-dimensional (2D) monolayers, but 3D cell organization, such as in spheroids, better mimics the complexity of solid tumors. To metastasize, cancer cells undergo the process of epithelial-to-mesenchymal transition (EMT) to become more invasive and pro-angiogenic, with expression of both epithelial and mesenchymal markers. Aims: We asked whether EMMPRIN/CD147 contributes to the formation of the 3D spheroid structure, and whether spheroids, which are often used to study proliferation and drug resistance, could better model the EMT process and the metastatic properties of cells, and improve our understanding of the role of EMMPRIN in them. Methods: We used the parental mouse CT26 colon carcinoma (CT26-WT) cells, and infected them with a lentivirus vector to knock down EMMPRIN expression (CT26-KD cells), or with an empty lentivirus vector (CT26-NC) that served as a negative control. In some cases, we repeated the experiments with the 4T1 or LLC cell lines. We compared the magnitude of change between CT26-KD and CT26-WT/NC cells in different metastatic properties in cells seeded as monolayers or as spheroids formed by the scaffold-free liquid overlay method. Results: We show that reduced EMMPRIN expression changed the morphology of cells and their spatial organization in both 2D and 3D models. The 3D models more clearly demonstrated how reduced EMMPRIN expression inhibited proliferation and the angiogenic potential, while it enhanced drug resistance, invasiveness, and EMT status, and moreover it enhanced cell dormancy and prevented CT26-KD cells from forming metastatic-like lesions when seeded on basement membrane extract (BME). Most interestingly, this approach enabled us to identify that EMMPRIN and miR-146a-5p form a negative feedback loop, thus identifying a key mechanism for EMMPRIN activities. These results underline EMMPRIN role as a gatekeeper that prevents dormancy, and suggest that EMMPRIN links EMT characteristics to the process of spheroid formation. Conclusions: Thus, 3D models can help identify mechanisms by which EMMPRIN facilitates tumor and metastasis progression, which might render EMMPRIN as a promising target for anti-metastatic tumor therapy.

Berberis vulgaris L. Root Extract as a Multi-Target Chemopreventive Agent against Colon Cancer Causing Apoptosis in Human Colon Adenocarcinoma Cell Lines.

Berberis vulgaris L. (Berberidaceae) is a shrub that has been widely used in European folk medicine as an anti-inflammatory and antimicrobial agent. The purpose of our study was to elucidate the mechanisms of the chemopreventive action of the plant's methanolic root extract (BVR) against colon cancer cells. Studies were conducted in human colon adenocarcinoma cell lines (LS180 and HT-29) and control colon epithelial CCD841 CoN cells. According to the MTT assay, after 48 h of cell exposure, the IC50 values were as follows: 4.3, 46.1, and 50.2 µg/mL for the LS180, HT-29, and CCD841 CoN cells, respectively, showing the greater sensitivity of the cancer cells to BVR. The Cell Death Detection ELISAPLUS kit demonstrated that BVR induced programmed cell death only against HT-29 cells. Nuclear double staining revealed the great proapoptotic BVR properties in HT-29 cells and subtle effect in LS180 cells. RT-qPCR with the relative quantification method showed significant changes in the expression of genes related to apoptosis in both the LS180 and HT-29 cells. The genes BCL2L1 (126.86-421.43%), BCL2L2 (240-286.02%), CASP3 (177.19-247.83%), and CASP9 (157.99-243.75%) had a significantly elevated expression, while BCL2 (25-52.03%) had a reduced expression compared to the untreated control. Furthermore, in a panel of antioxidant tests, BVR showed positive effects (63.93 ± 0.01, 122.92 ± 0.01, and 220.29 ± 0.02 mg Trolox equivalents (TE)/g in the DPPH•, ABTS•+, and ORAC assays, respectively). In the lipoxygenase (LOX) inhibition test, BVR revealed 62.60 ± 0.87% of enzyme inhibition. The chemical composition of BVR was determined using a UHPLC-UV-CAD-MS/MS analysis and confirmed the presence of several known alkaloids, including berberine, as well as other alkaloids and two derivatives of hydroxycinnamic acid (ferulic and sinapic acid hexosides). The results are very promising and encourage the use of BVR as a comprehensive chemopreventive agent (anti-inflammatory, antioxidant, and pro-apoptotic) in colorectal cancer, and were widely discussed alongside data from the literature.

Unlocking the paracrine crosstalk: adipocyte-derived factors affect carbonic anhydrase IX expression in colon and breast cancer cells.

Obesity is a major public health concern because it increases the risk of several diseases, including cancer. Crosstalk between obesity and cancer seems to be very complex, and the interaction between adipocytes and cancer cells leads to changes in adipocytes' function and their paracrine signaling, promoting a microenvironment that supports tumor growth. Carbonic anhydrase IX (CA IX) is a tumor-associated enzyme that not only participates in pH regulation but also facilitates metabolic reprogramming and supports the migration, invasion, and metastasis of cancer cells. In addition, CA IX expression, predominantly regulated via hypoxia-inducible factor (HIF-1), serves as a surrogate marker of hypoxia. In this study, we investigated the impact of adipocytes and adipocyte-derived factors on the expression of CA IX in colon and breast cancer cells. We observed increased expression of CA9 mRNA as well as CA IX protein in the presence of adipocytes and adipocyte-derived conditioned medium. Moreover, we confirmed that adipocytes affect the hypoxia signaling pathway and that the increased CA IX expression results from adipocyte-mediated induction of HIF-1α. Furthermore, we demonstrated that adipocyte-mediated upregulation of CA IX leads to increased migration and decreased adhesion of colon cancer cells. Finally, we brought experimental evidence that adipocytes, and more specifically leptin, upregulate CA IX expression in cancer cells and consequently promote tumor progression.

The Hippo pathway terminal effector TAZ/WWTR1 mediates oxaliplatin sensitivity in p53 proficient colon cancer cells.

YAP and TAZ, the Hippo pathway terminal transcriptional activators, are frequently upregulated in cancers. In tumor cells, they have been mainly associated with increased tumorigenesis controlling different aspects from cell cycle regulation, stemness, or resistance to chemotherapies. In fewer cases, they have also been shown to oppose cancer progression, including by promoting cell death through the action of the p73/YAP transcriptional complex, in particular after chemotherapeutic drug exposure. Using HCT116 cells, we show here that oxaliplatin treatment led to core Hippo pathway down-regulation and nuclear accumulation of TAZ. We further show that TAZ was required for the increased sensitivity of HCT116 cells to oxaliplatin, an effect that appeared independent of p73, but which required the nuclear relocalization of TAZ. Accordingly, Verteporfin and CA3, two drugs affecting the activity of YAP and TAZ, showed antagonistic effects with oxaliplatin in co-treatments. Importantly, using several colorectal cell lines, we show that the sensitizing action of TAZ to oxaliplatin is dependent on the p53 status of the cells. Our results support thus an early action of TAZ to sensitize cells to oxaliplatin, consistent with a model in which nuclear TAZ in the context of DNA damage and p53 activity pushes cells towards apoptosis.

Macromolecules with predominant ß-pleated sheet proteins in extracellular vesicles released from Raphanus sativus L. var. caudatus Alef microgreens induce DNA damage-mediated apoptosis in HCT116 colon cancer cells.

Plant-derived bioactive macromolecules (i.e., proteins, lipids, and nucleic acids) were prepared as extracellular vesicles (EVs). Plant-derived EVs are gaining pharmaceutical research interest because of their bioactive components and delivery properties. The spherical nanosized EVs derived from Raphanus sativus L. var. caudatus Alef microgreens previously showed antiproliferative activity in HCT116 colon cancer cells from macromolecular compositions (predominantly proteins). To understand the mechanism of action, the biological activity studies, i.e., antiproliferation, cellular biochemical changes, DNA conformational changes, DNA damage, apoptotic nuclear morphological changes, apoptosis induction, and apoptotic pathways, were determined by neutral red uptake assay, synchrotron radiation-based Fourier transform infrared microspectroscopy, circular dichroism spectroscopy, comet assay, 4',6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and caspase activity assay, respectively. EVs inhibited HCT116 cell growth in concentration- and time-dependent manners, with a half-maximal inhibitory concentration of 675.4 ± 33.8 µg/ml at 48 h and a selectivity index of 1.5 ± 0.076. HCT116 treated with EVs mainly changed the cellular biochemical compositions in the nucleic acids and carbohydrates region. The DNA damage caused no changes in DNA conformation. The apoptotic nuclear morphological changes were associated with the increased apoptotic cell population. The apoptotic cell death was induced by both extrinsic and intrinsic pathways. EVs have potential as antiproliferative bioparticles.

Semisynthesis and biological evaluation of novel honokiol thioethers against colon cancer cells HCT116 via inhibiting the transcription and expression of YAP protein.

Honokiol, derived from Magnolia officinalis (a traditional Chinese medicine), has been reported to have anticancer activity. Here, a series of novel honokiol thioethers bearing a 1,3,4-oxadiazole moiety were prepared and evaluated for their anticancer activities against three types of digestive system tumor cells. Biological evaluation showed that honokiol derivative 3k exhibited the best antiproliferative activity against HCT116 cells with an IC50 value of 6.1 µmol/L, superior to the reference drug 5-fluorouracil (IC50: 9.63 ± 0.27 µmol/L). The structure-activity relationships (SARs) indicated that the introduction of -(4-NO2)Ph, 3-pyridyl, -(2-F)Ph, -(4-F)Ph, -(3-F)Ph, -(4-Cl)Ph, and -(3-Cl)Ph groups was favorable for enhancing the anticancer activity of the title honokiol thioethers. Further study revealed that honokiol thioether 3k can well inhibit the proliferation of colon cancer cells HCT116, arresting the cells in G1 phase and inducing cell death. Moreover, a preliminary mechanism study indicated that 3k directly inhibits the transcription and expression of YAP protein without activating the Hippo signaling pathway. Thus, honokiol thioether 3k could be deeply developed for the development of honokiol-based anticancer candidates.

NSUN6 mediates 5-methylcytosine modification of METTL3 and promotes colon adenocarcinoma progression.

Colon adenocarcinoma (COAD) is a common and fatal malignant tumor of digestive system with complex etiology. 5-Methylcytosine (m5C) modification of RNA by the NSUN gene family (NSUN1-NSUN7) and DNMT2 reshape cell biology and regulate tumor development. However, the expression profile, prognostic significance and function of these m5C modifiers in COAD remain largely unclear. By mining multiple integrated tumor databases, we found that NSUN1, NSUN2, NSUN5, and NSUN6 were overexpressed in COAD tumor samples relative to normal samples. Clinically, high expression of NSUN6 was significantly associated with shorter survival (including both disease-free survival and overall survival) in COAD patients. NSUN6 was further confirmed to be upregulated at both tissue and cellular levels of COAD, suggesting that NSUN6 plays a critical role in disease progression. Through comprehensive gene enrichment analysis and cell-based functional validation, it was revealed that NSUN6 promoted the cell cycle progression and cell proliferation of COAD. Mechanistically, NSUN6 upregulates the expression of oncogenic METTL3 and catalyzes its m5C modification in COAD cells. Overexpression of METTL3 significantly relieved the cell cycle inhibition of COAD caused by NSUN6 deficiency. Furthermore, NSUN6 was negatively associated with the abundance of infiltrating immune cells in COAD tumors, such as activated B cells, natural killer cells, effector memory CD8 T cells, and regulatory T cells. Importantly, pan-cancer analysis further uncovered that NSUN6 was dysregulated and heterogeneous in various tumors. Thus our findings extend the role of m5C transferase in COAD and suggest that NSUN6 is a potential biomarker and target for this malignancy.

Network-based elucidation of colon cancer drug resistance mechanisms by phosphoproteomic time-series analysis.

Aberrant signaling pathway activity is a hallmark of tumorigenesis and progression, which has guided targeted inhibitor design for over 30 years. Yet, adaptive resistance mechanisms, induced by rapid, context-specific signaling network rewiring, continue to challenge therapeutic efficacy. Leveraging progress in proteomic technologies and network-based methodologies, we introduce Virtual Enrichment-based Signaling Protein-activity Analysis (VESPA)-an algorithm designed to elucidate mechanisms of cell response and adaptation to drug perturbations-and use it to analyze 7-point phosphoproteomic time series from colorectal cancer cells treated with clinically-relevant inhibitors and control media. Interrogating tumor-specific enzyme/substrate interactions accurately infers kinase and phosphatase activity, based on their substrate phosphorylation state, effectively accounting for signal crosstalk and sparse phosphoproteome coverage. The analysis elucidates time-dependent signaling pathway response to each drug perturbation and, more importantly, cell adaptive response and rewiring, experimentally confirmed by CRISPR knock-out assays, suggesting broad applicability to cancer and other diseases.