Current targeted therapies in the treatment of advanced colorectal cancer: a review

Microbubble Enhanced Delivery of Vitamin C for Treatment of Colorectal Cancer

During chemotherapy treatment for cancer, often only a fraction of the administered dose reaches the tumor site, with the remaining drug spreading throughout the body, producing unwanted side-effects and restricting how much drug can be safely administered. A potential solution to reduce this problem is the use of microbubbles. The interaction between microbubbles and ultrasound generates pores in the tumor cells, permitting enhanced drug uptake. This study investigates the delivery of the ascorbic acid derivative, palmitoyl ascorbate, to KRAS-mutated colorectal cancer cells in vitro. Ultrasound-triggered microbubbles enhanced the efficacy of liposomal palmitoyl ascorbate treatments by 1.7- and 2.2-fold in LS174T and HCT116 CRC cell lines, respectively. This enhancement was achieved without increasing the drug dosage, and the therapeutic effect was shown to be localized to the area that received the ultrasound pulse, aiding in the reduction of off-site toxicity.

Transforming growth factor-β (TGF-β) signaling pathway-related genes in predicting the prognosis of colon cancer and guiding immunotherapy

Background

Colon cancer is a malignant tumor with high malignancy and a low survival rate whose heterogeneity limits systemic immunotherapy. Transforming growth factor-β (TGF-β) signaling pathway-related genes are associated with multiple tumors, but their role in prognosis prediction and tumor microenvironment (TME) regulation in colon cancer is poorly understood. Using bioinformatics, this study aimed to construct a risk prediction signature for colon cancer, which may provide a means for developing new effective treatment strategies.

Methods

Using consensus clustering, patients in The Cancer Genome Atlas (TCGA) with colon adenocarcinoma were classified into several subtypes based on the expression of TGF-β signaling pathway-related genes, and differences in survival, molecular, and immunological TME characteristics and drug sensitivity were examined in each subtype. Ten genes that make up a TGF-β-related predictive signature were found by least absolute shrinkage and selector operation (LASSO) regression using colon cancer data from the TCGA database and confirmed using a Gene Expression Omnibus (GEO) dataset. A nomogram incorporating risk scores and clinicopathologic factors was developed to stratify the prognosis of patients with colon cancer for accurate clinical diagnosis and therapy.

Results

Two TGF-β subtypes were identified, with the TGF-β-high subtype being associated with a poorer prognosis and superior sensitivity to immunotherapy. Mutation analyses showed a high incidence of gene mutations in the TGF-β-high subtype. After completing signature construction, patients with colon cancer were categorized into high- and low-risk subgroups based on the median risk score of the TGF-β-related predictive signature. The risk score exhibited superior predictive performance relative to age, gender, and stage, as evidenced by its AUC of 0.686. Patients in the high-risk subgroup had higher levels of immunosuppressive cell infiltration and immune checkpoints in the TME, suggesting that these patients had better responses to immunotherapy.

Conclusions

Patients with colon cancer were divided into two subtypes with different survival and immune characteristics using consensus clustering analysis based on TGF-β signaling pathway-related genes. The constructed risk prediction signature may show promise as a biomarker for evaluating the prognosis of colon cancer, with potential utility for screening individuals for immunotherapy.

Novel drug delivery systems in colorectal cancer: Advances and future prospects

Colorectal cancer (CRC) is an abnormal proliferation of cells within the colon and rectum, leading to the formation of polyps and disruption of mucosal functions. The disease development is influenced by a combination of factors, including inflammation, exposure to environmental mutagens, genetic alterations, and impairment in signaling pathways. Traditional treatments such as surgery, radiation, and chemotherapy are often used but have limitations, including poor solubility and permeability, treatment resistance, side effects, and post-surgery issues. Novel Drug Delivery Systems (NDDS) have emerged as a superior alternative, offering enhanced drug solubility, precision in targeting cancer cells, and regulated drug release. Thereby addressing the shortcomings of conventional therapies and showing promise for more effective CRC management. The present review sheds light on the pathogenesis, signaling pathways, biomarkers, conventional treatments, need for NDDS, and application of NDDS against CRC. Additionally, clinical trials, ongoing clinical trials, marketed formulations, and patents on CRC are also covered in the present review.

Decreased aggressive care at the end of life among advanced cancer patients in the Republic of Korea: a nationwide study from 2012 to 2018

BACKGROUND

This study aimed to investigate the trends of aggressive care at the end-of-life (EoL) for patients with advanced cancer in Korea and to identify factors affecting such care analyzing nationwide data between 2012 to 2018.

METHODS

This was a population-based, retrospective nationwide study. We used administrative data from the National Health Insurance Service and the Korea Central Cancer Registry to analyze 125,350 patients aged 20 years and above who died within one year of a stage IV cancer diagnosis between 2012 and 2018.

RESULTS

The overall aggressiveness of EoL care decreased between 2012 and 2018. In patients' last month of life, chemotherapy use (37.1% to 32.3%; p < 0.05), cardiopulmonary resuscitation (13.2% to 10.4%; p < 0.05), and intensive care unit admission (15.2% to 11.1%; p < 0.05) decreased during the study period, although no significant trend was noted in the number of emergency room visits. A steep increase was seen in inpatient hospice use in the last month of life (8.6% to 26.6%; p < 0.05), while downward trends were observed for hospice admission within three days prior to death (13.9% to 11%; p < 0.05). Patients were more likely to receive aggressive EoL care if they were younger, women, had treatment in tertiary hospitals, or had hematologic malignancies. In the subgroup analysis, the overall trend of aggressive EoL care decreased for all five major cancer types.

CONCLUSION

The aggressiveness of EoL care in stage IV cancer patients showed an overall decrease during 2012-2018 in Korea.

Sevoflurane suppresses colorectal cancer malignancy by modulating β-catenin ubiquitination degradation via circSKA3

BACKGROUND

Sevoflurane (SEV), a commonly used inhalational anesthetic, reportedly inhibits colorectal cancer (CRC) malignancy, but whether SEV can inhibit the malignancy of CRC by regulating circular RNAs (circRNAs) remains unclear. Therefore, we aimed to identify specific circRNAs that may be affected by SEV and to investigate their functional roles in CRC.

METHODS

RT-qPCR was employed to detect the expression of circRNAs and mRNAs in CRC cells and tissues. Fluorescence in situ hybridization (FISH) was used to determine the location of circSKA3. Protein expression was assessed by western blot analysis. Function-based in vitro and in vivo experiments, including CCK-8, colony formation, transwell, and apoptosis assays and mouse xenograft tumor models, were conducted using circSKA3-knockdown and circSKA3-overexpression cell lines. RNA immunoprecipitation, RNA pull-down and mass spectrometry analyses were performed to explore the related mechanism.

RESULTS

Our findings revealed that SEV could inhibit CRC cell activity, proliferation and migration and promote apoptosis in CRC cells. We found that circSKA3 was upregulated in CRC and associated with poorer survival and that its expression could be reduced by SEV. The overexpression of circSKA3 reversed the effects of SEV on inhibiting cell activity, proliferation and migration and promoting apoptosis. The mechanistic analysis revealed that circSKA3 could bind to the ARM structural domain of β-catenin and thereby disrupt its interaction with the CK1/GSK3β/β-TrCP1 destruction complex, resulting in the ubiquitinated degradation of β-catenin and the activation of Wnt/β-catenin signaling. In addition, SEV downregulated circSKA3 in vivo to inhibit tumor growth.

CONCLUSIONS

All the results showed that SEV could inhibit CRC progression via circSKA3 by increasing β-catenin ubiquitination degradation.

A perspective on emerging therapies in metastatic colorectal cancer: Focusing on molecular medicine and drug resistance

The majority of cancer cases are colorectal cancer, which is also the second largest cause of cancer-related deaths worldwide. Metastasis is the leading cause of death for patients with colorectal cancer. Metastatic colorectal cancer incidence are on the rise due to a tiny percentage of tumors developing resistant to medicines despite advances in treatment tactics. Cutting-edge targeted medications are now the go-to option for customized and all-encompassing CRC care. Specifically, multitarget kinase inhibitors, antivascular endothelial growth factors, and epidermal growth factor receptors are widely used in clinical practice for CRC-targeted treatments. Rare targets in metastatic colorectal cancer are becoming more well-known due to developments in precision diagnostics and the extensive use of second-generation sequencing technology. These targets include the KRAS mutation, the BRAF V600E mutation, the HER2 overexpression/amplification, and the MSI-H/dMMR. Incorporating certain medications into clinical trials has significantly increased patient survival rates, opening new avenues and bringing fresh viewpoints for treating metastatic colorectal cancer. These focused therapies change how cancer is treated, giving patients new hope and better results. These markers can significantly transform and individualize therapy regimens. They could open the door to precisely customized and more effective medicines, improving patient outcomes and quality of life. The fast-growing body of knowledge regarding the molecular biology of colorectal cancer and the latest developments in gene sequencing and molecular diagnostics are directly responsible for this advancement.

Construction and validation of a novel angiogenesis pattern to predict prognosis and immunotherapy efficacy in colorectal cancer

BACKGROUND

Evidence suggests that the tumor microenvironment (TME) affects the tumor active response to immunotherapy. Tumor angiogenesis is closely related to the TME. Nonetheless, the effects of angiogenesis on the TME of colorectal cancer (CRC) remain unknown.

METHODS

We comprehensively assessed the angiogenesis patterns in CRC based on 36 angiogenesis-related genes (ARGs). Subsequently, we evaluated the prognostic values and therapeutic sensitivities of angiogenesis patterns using multiple methods. We then performed the machine learning algorithm and functional experiments to identify the prognostic key ARGs. Ultimately, the regulation of gut microbiota on the expression of ARGs was further investigated by using whole genome sequencing.

RESULTS

Two angiogenesis clusters were identified and angiogenesis cluster B was characterized by increased stromal and immunity activation with unfavorable odds of survival. Further, an ARG_score including 9 ARGs to predict recurrence-free survival (RFS) was established and its predominant predictive ability was confirmed. The low ARG_score patients were characterized by a high mutation burden, high microsatellite instability, and immune activation with better prognosis. Moreover, patients with high KLK10 expression were associated with a hot tumor immune microenvironment, poorer immune checkpoint blocking treatment, and shorter survival. The in vitro experiments also indicated that Fusobacterium nucleatum (F.n) infection significantly induced KLK10 expression in CRC.

CONCLUSIONS

The quantification of angiogenesis patterns could contribute to predict TME characteristics, prognosis, and individualized immunotherapy strategies. Furthermore, our findings suggest that F.n may influence CRC progression through ARGs, which could serve as a clinical biomarker and therapeutic target for F.n-infected CRC patients.

Studies on 1,4-Quinone Derivatives Exhibiting Anti-Leukemic Activity along with Anti-Colorectal and Anti-Breast Cancer Effects

Colorectal cancer (CRC), breast cancer, and chronic myeloid leukemia (CML) are life-threatening malignancies worldwide. Although potent therapeutic and screening strategies have been developed so far, these cancer types are still major public health problems. Therefore, the exploration of more potent and selective new agents is urgently required for the treatment of these cancers. Quinones represent one of the most important structures in anticancer drug discovery. We have previously identified a series of quinone-based compounds (ABQ-1-17) as anti-CML agents. In the current work, ABQ-3 was taken to the National Cancer Institute (NCI) for screening to determine its in vitro antiproliferative effects against a large panel of human tumor cell lines at five doses. ABQ-3 revealed significant growth inhibition against HCT-116 CRC and MCF-7 breast cancer cells with 2.00 µM and 2.35 µM GI₅₀ values, respectively. The MTT test also showed that ABQ-3 possessed anticancer effects towards HCT-116 and MCF-7 cells with IC₅₀ values of 5.22 ± 2.41 μM and 7.46 ± 2.76 μM, respectively. Further experiments indicated that ABQ-3 induced apoptosis in both cell lines, and molecular docking studies explicitly suggested that ABQ-3 exhibited DNA binding in a similar fashion to previously reported compounds. Based on in silico pharmacokinetic prediction, ABQ-3 might display drug-like features enabling this compound to become a lead molecule for future studies.

A novel enterocyte-related 4-gene signature for predicting prognosis in colon adenocarcinoma

Background

Colon adenocarcinoma (COAD) is a fatal disease, and its cases are constantly increasing worldwide. Further, the therapeutic and management strategies for patients with COAD are still unsatisfactory due to the lack of accurate patient classification and prognostic models. Therefore, our study aims to identify prognostic markers in patients with COAD and construct a cell subtype-specific prognostic model with high accuracy and robustness.

Methods

Single-cell transcriptomic data of six samples were retrieved from the Gene expression omnibus (GEO) database. The cluster annotation and cell-cell communication analysis identified enterocytes as a key player mediating signal communication networks. A four-gene signature prognostic model was constructed based on the enterocyte-related differentially expressed genes (ERDEGs) in patients with COAD of the Cancer Genome Atlas cohort. The prognostic model was validated on three external validation cohorts from the GEO database. The correlation between immune cell infiltration, immunotherapy response, drug sensitivity, and the four-gene signature prognostic model was investigated. Finally, immunohistochemistry (IHC) was performed to determine the expression of the four genes.

Results

We found that the proportion of epithelial cells was obviously large in COAD samples. Further analysis of epithelial cells showed that the activity of the enterocytes was highest in the cell-cell communication network. Based on enterocyte data, 30 ERDEGs were identified and a 4-gene prognostic model including CPM, CLCA4, ELOVL6, and ATP2A3 was developed and validated. The risk score derived from this model was considered as an independent variable factor to predict overall survival. The patients were divided into high- and low-risk groups based on the median riskscore value. The correlation between immune cell infiltration, immunotherapy response, immune status, clinical characteristics, drug sensitivity, and risk score was analyzed. IHC confirmed the expression of signature genes in tissues from normal individuals, patients with polyps, and COAD.

Conclusion

In this study, we constructed and validated a novel four-gene signature prognostic model, which could effectively predict the response to immunotherapy and overall survival in patients with COAD. More importantly, this model provides useful insight into the management of colon cancer patients and aids in designing personalized therapy.

miR-146a-5p and miR-193a-5p Synergistically Inhibited the Proliferation of Human Colorectal Cancer Cells (HT-29 cell line) through ERK Signaling Pathway

Purpose: The expression of miR-146a-5p and miR-193a-5p in colorectal cancer (CRC) is associated with cancer development, metastasis, and reduced survival rate of the tumor-suffered subjects. This examination aimed to assess the impact of these microRNAs (miRNAs) in CRC and their mechanisms in the proliferation and migration of cancer cells.

Methods: miR-146a-5p and -193a-5p were transfected into the HT-29 cell line and assessed their impact on metastasis-related genes. The synergistic effects of these miRNAs on migration were evaluated by wound healing approach. To assess the influence of these miRNAs on the proliferation of and apoptosis of cells, the MTT test, annexin V staining test, and DAPI staining test were done. Then, the protein expression of extracellular-signal-regulated kinase (ERK) and phosphorylated ERK (p-ERK) were investigated.

Results: miR-146a-5p and-193a-5p could inhibit the CRC cells proliferation, and could synergistically induce apoptosis in CRC cells, and also repressed cell migration, and could reduce p-ERK expression.

Conclusion: miR-146a-5p and-193a-5p have an important role in cell viability and proliferation via ERK signaling pathway. Thus, the simultaneous use of these miRNAs may be suggested as a probable therapeutic strategy in this cancer therapy.

Long Non-Coding RNA CCAT2 Activates RAB14 and Acts as an Oncogene in Colorectal Cancer

Here, we investigated the clinicopathological and prognostic potential of the long noncoding RNA Colon Cancer-Associated Transcript 2 (CCAT2) in human colorectal cancer (CRC). We used qPCR to quantify CCAT2 levels in 44 pairs of CRC tissues and adjacent nontumor and healthy colon mucosa tissues, and in several CRC cell lines (SW620, SW480, HT-29, LOVO, HCT116 and DLD-1) and normal human colorectal epithelial cells (HFC). We assessed the effects of CCAT2 overexpression or knockdown on the proliferation, migration and invasion by SW620 and LOVO cells using CCK-8, transwell, and wound-healing assays, respectively. We also investigated the potential interaction between CCAT2 and TAF15 through RNA pull down and rescue experiments. Lastly, we evaluated the expression of the cell cycle progression markers and GSK3β signaling pathway proteins using Western blotting. Our results showed that CCAT2 was upregulated in CRC tissues and cell lines as com-pared to controls. Ectopic expression of CCAT2 promoted CRC cell proliferation, migration and invasion, likely through direct interaction with TAF15, transcriptional activation of RAB14, and activation of the AKT/GSK3β signaling pathway. In vivo, CCAT2 promoted CRC cell growth and metastasis in nude mice. Taken together, these results highlight the actions of CCAT2 as a CRC oncogene.

Isolation and Identification of Long Non-Coding RNAs in Exosomes Derived from the Serum of Colorectal Carcinoma Patients

Simple Summary

Treatment regimens for patients with advanced disease are limited and the mortality rate is high in these patients. A better understanding on pathogenesis and progression of cancer is critical for the development of new treatment strategies. In colorectal cancer (CRC), exosomes (secreted vesicles from cells) and long non-coding RNAs (lncRNAs) have been shown to play significant roles in disease development and progression. Long non-coding RNAs (lncRNAs) are present in the exosomes of serum and their profiles may potentially be useful as novel biomarkers for CRC patients and may provide a new insight in the pathogenesis and progression of CRC. Here, we compared the expression profiles of exosomal lncRNAs between non-cancer individuals and patients with colorectal carcinoma. The relative expression level of LINC00152 was found to be significantly lower in exosomes from sera of CRC patients as compared to non-cancer individuals whereas lncRNA H19 was significantly up-regulated in advanced-stages (stage III and IV) of CRC as compared to early-stages (stage I and II). Our data suggest that LINC00152 and H19 may play important roles in pathogenesis and progression of CRC.

Abstract

Long non-coding RNAs (lncRNAs) are non-coding RNAs consisting of more than 200 nucleotides in length. LncRNAs present in exosomes may play a critical role in the cellular processes involved in cancer pathogenesis and progression including proliferation, invasion, and migration of tumor cells. This paper aims to identify the differential expression of exosomal lncRNAs derived from the sera of non-cancer individuals and patients diagnosed with colorectal carcinoma. These differentially-expressed exosomal serum lncRNAs may provide an insight into the pathogenesis and progression of colorectal cancer (CRC). Serum exosomes and exosomes from SW480-7 cell culture supernatants were isolated and viewed by transmission electron microscope (TEM). The particle size distribution and protein markers of exosomes derived from SW480-7 were further analyzed using the Zetasizer Nano S instrument and western blotting technique. TEM showed that exosomes derived from serum and SW480-7 cells were round vesicles with sizes ranging from 50–200 nm. The exosomes derived from SW480-7 had an average diameter of 274.6 nm and contained the exosomal protein, ALIX/PDCD6IP. In our clinical studies, six lncRNAs, namely GAS5, H19, LINC00152, SNHG16, RMRP, and ZFAS1 were detected in the exosomes from sera of 18 CRC patients. Among these six lncRNAs, the expression level of LINC00152 was found to be significantly lower in CRC patients as compared to non-cancer individuals (p = 0.04) while lncRNA H19 was significantly up-regulated in advanced-stages (stage III and IV) of CRC (p = 0.04) as compared to early-stages (stage I and II). In conclusion, the detection of lower LINC00152 in exosomes of sera from CRC patients versus non-cancer individuals and H19 upregulation in advanced stages suggests that they may play important roles in pathogenesis and progression of CRC.

Sevoflurane inhibits malignant progression of colorectal cancer via hsa_circ_0000231-mediated miR-622

Background

Sevoflurane (Sev), a commonly used volatile anesthetic, has been reported to inhibit the process of colorectal cancer (CRC). Circular RNAs (circRNAs) are revealed to participate in the pathogenesis of CRC. This study aims to reveal the mechanism of hsa_circ_0000231 in Sev-mediated CRC progression.

Methods

The expression of hsa_circ_0000231 and microRNA-622 (miR-622) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Protein level was determined by western blot analysis. Cell proliferation was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cell colony formation and DNA content quantitation assays. Cell apoptosis was detected by Annexin V-fluorescein isothiocyanate and propidium iodide double staining and caspase 3 activity assays. Cell migration and invasion were investigated by wound-healing and transwell invasion assays, respectively. The putative relationship between hsa_circ_0000231 and miR-622 was predicted by circular RNA Interactome online database, and identified by dual-luciferase reporter and RNA immunoprecipitation assays. The impacts of hsa_circ_0000231 on Sev-mediated tumor formation in vivo were presented by in vivo assay.

Results

Hsa_circ_0000231 expression was upregulated, while miR-622 was downregulated in CRC tissues and cells compared with control groups. Sev treatment decreased hsa_circ_0000231 expression, but increased miR-622 expression in CRC cells. Sev treatment suppressed cell proliferation, migration and invasion, and induced cell apoptosis. Hsa_circ_0000231 overexpression restored Sev-mediated CRC progression in vitro. Additionally, hsa_circ_0000231 acted as a sponge of miR-622, and miR-622 inhibitors reversed the impacts of hsa_circ_0000231 silencing on CRC process. Furthermore, Sev treatment inhibited tumor growth by regulating hsa_circ_0000231 in vivo.

Conclusion

Hsa_circ_0000231 attenuated Sev-aroused repression impacts on CRC development by sponging miR-622. This findings may provide an appropriate anesthetic protocol for CRC sufferers undergoing surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40709-021-00145-6.

Momordin Ic induces G0/1 phase arrest and apoptosis in colon cancer cells by suppressing SENP1/c-MYC signaling pathway

Momordin Ic (MI) is a natural pentacyclic triterpenoid enriched in various Chinese natural medicines such as the fruit of Kochia scoparia (L.) Schrad. Studies have shown that MI presents antitumor properties in liver and prostate cancers. However, the activity and potential mechanisms of MI against colorectal cancer remain elusive. Here, we showed that MI inhibited cell proliferation with G0/1 phase cell cycle arrest in colon cancer cells. Moreover, it was observed that MI increased apoptosis compared to untreated cells. Further investigation showed that the SUMOylation of c-Myc was enhanced by MI and led to the down-regulated protein level of c-Myc, which is involved in regulating cell proliferation and apoptosis. SENP1 has been demonstrated to be critical for the SUMOylation of c-Myc. Meanwhile, knockdown of SENP1 by siRNA abolished the effects of MI on c-Myc level and cell viability in colon cancer cells. Together, these results revealed that MI exerted an anti-tumor activity in colon cancer cells via SENP1/c-Myc signaling pathway. These finding provide an insight into the potential of MI for colon cancer therapy.

High expression of FABP4 in colorectal cancer and its clinical significance

OBJECTIVES

To investigate the relationship between the fatty acid-binding protein 4 (FABP4) and colorectal cancer (CRC).

METHODS

Using an enzyme-linked immunosorbent assay (ELISA), we measured the expression of FABP4 in plasma of 50 patients who underwent surgery for CRC from October 2017 to May 2018 and 50 healthy controls. The content of the visceral fat area (VFA) as seen with abdominal computed tomography (CT) scanning was measured by ImageJ software. The expression levels of FABP4, E-cadherin, and Snail proteins in CRC and adjacent tissues were determined by immunohistochemistry.

RESULTS

The mean concentration of plasma FABP4 of CRC patients was higher than that of the control group (22.46 vs. 9.82 ng/mL; P<0.05). The concentration of plasma FABP4 was related to the tumor, node, metastatis (TNM) stage and lymph node metastasis and was independent of age, body mass index (BMI), tumor size and location, and the degree of differentiation of CRC. The concentration of plasma FABP4 was positively correlated with high VFA and lipoprotein-a (LPA) (P<0.05); but it was not correlated with total cholesterol (TG), total triglyceride (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), or apolipoprotein AI (Apo-AI). The expression of FABP4 protein in CRC tissues was positively correlated with the degree of CRC differentiation, tumor stage, and lymph node metastasis. The level of FABP4 protein was negatively correlated with E-cadherin protein (r=-0.3292, P=0.0196) and positively correlated with Snail protein (r=0.5856, P<0.0001).

CONCLUSIONS

High LPA and VFA were risk factors for increased plasma FABP4 in CRC patients. FABP4 protein was highly expressed in CRC tissues and associated with TNM stage, differentiation, and lymph node metastasis of CRC. The level of FABP4 in CRC tissue was correlated with E-cadherin and Snail expression, suggesting that FABP4 may promote CRC progression related to epithelial-mesenchymal transition (EMT).

Circular RNA 100146 Promotes Colorectal Cancer Progression by the MicroRNA 149/HMGA2 Axis

Colorectal cancer (CRC) has developed into the third leading cause of cancer-associated death worldwide. Studies have confirmed that circular RNAs (circRNAs) absorb microRNAs (miRNAs) to regulate the function of downstream genes. This study aimed to explore the underlying mechanism of circRNA 100146 in CRC. The expression of circRNA 100146, miRNA 149 (miR-149), and high mobility group AT-Hook 2 (HMGA2) was detected by quantitative real-time PCR (RT-qPCR). A series of biofunctional effects (cell viability, apoptosis, migration/invasion) were evaluated by the use of methyl thiazolyl tetrazolium (MTT), flow cytometry, and transwell assays. Protein levels were measured by Western blot assay. A xenograft model was established for in vivo experiments. The interactions among circRNA 100146, miR-149, and HMGA2 were evaluated by dual-luciferase reporter assay, RNA immunoprecipitation assays, or RNA pulldown assay. circRNA 100146 was upregulated in CRC tissues and cells. circRNA 100146 knockdown inhibited cell proliferation, promoted apoptosis, and suppressed migration and invasion in vitro and impeded tumor growth in vivo Also, miR-149 was negatively regulated by circRNA 100146 and was targeted to HMGA2 and mediated its expression. Moreover, miR-149 interference abrogated the activities of silenced circRNA 100146 in proliferation, apoptosis, migration, and invasion. Furthermore, HMGA2 overexpression abated the effects described above caused by circRNA 100146 silencing, while the mutations on miR-149 binding sites in the 3' untranslated region (3'-UTR) of HMGA2 led to its loss of this ability. circRNA 100146 knockdown repressed proliferation, enhanced apoptosis, and hindered migration and invasion in SW620 and SW480 cells through targeting the miR-149/HMGA2 axis.

Combined blockade of EGFR and glutamine metabolism in preclinical models of colorectal cancer

Improving response to epidermal growth factor receptor (EGFR)-targeted therapies in patients with advanced wild-type (WT) RAS colorectal cancer (CRC) remains an unmet need. In this preclinical work, we evaluated a new therapeutic combination aimed at enhancing efficacy by targeting cancer cell metabolism in concert with EGFR. We hypothesized that combined blockade of glutamine metabolism and EGFR represents a promising treatment approach by targeting both the "fuel" and "signaling" components that these tumors need to survive. To explore this hypothesis, we combined CB-839, an inhibitor of glutaminase 1 (GLS1), the mitochondrial enzyme responsible for catalyzing conversion of glutamine to glutamate, with cetuximab, an EGFR-targeted monoclonal antibody in preclinical models of CRC. 2D and 3D in vitro assays were executed following treatment with either single agent or combination therapy. The combination of cetuximab with CB-839 resulted in reduced cell viability and demonstrated synergism in several cell lines. In vivo efficacy experiments were performed in cell-line xenograft models propagated in athymic nude mice. Tumor volumes were measured followed by immunohistochemical (IHC) analysis of proliferation (Ki67), mechanistic target of rapamycin (mTOR) signaling (pS6), and multiple mechanisms of cell death to annotate molecular determinants of response. In vivo, a significant reduction in tumor growth and reduced Ki67 and pS6 IHC staining were observed with combination therapy, which was accompanied by increased apoptosis and/or necrosis. The combination showed efficacy in cetuximab-sensitive as well as resistant models. In conclusion, this therapeutic combination represents a promising new precision medicine approach for patients with refractory metastatic WT RAS CRC.

Sevoflurane suppresses cell viability and invasion and promotes cell apoptosis in colon cancer by modulating exosome‑mediated circ‑HMGCS1 via the miR‑34a‑5p/SGPP1 axis

As a novel halogenated hydroxyl ether-inhaled general anesthetic, sevoflurane has been reported to affect the progression of diverse human cancers. In the present study, we aimed to explore the functions and underlying mechanisms of sevoflurane in colon cancer. MTT assay, flow cytometric analysis and Transwell assay were conducted to evaluate cell viability, apoptosis and invasion, respectively. Western blot analysis was performed to determine the protein level of sphingosine-1-phosphate phosphatase 1 (SGPP1). The morphology and size of exosomes were analyzed by TEM and NTA. The levels of circular RNA 3-hydroxy-3-methylglutaryl-CoA synthase 1 (circ-HMGCS1), microRNA (miR)-34a-5p and SGPP1 mRNA were examined by RT-qPCR. Dual-luciferase reporter and RNA RIP assays were utilized to explore the interaction between miR-34a-5p and circ-HMGCS1 or SGPP1. A murine xenograft model was established to investigate the effect of circ-HMGCS1 in vivo. As a result, it was determined that sevoflurane suppressed cell viability and invasion and induced apoptosis in colon cancer in a dose-dependent way. Exosomal circ-HMGCS1 was increased in the serums and cells of colon cancer patients. Circ-HMGCS1 was downregulated by sevoflurane treatment in colon cancer cells and circ-HMGCS1 overexpression could restore the effect of sevoflurane on colon cancer cell development. miR-34a-5p was a target of circ-HMGCS1 and miR-34a-5p inhibition reversed the effect of circ-HMGCS1 silencing on colon cancer cell progression. Moreover, circ-HMGCS1 knockdown suppressed SGPP1 expression via sponging miR-34a-5p. Knockdown of circ-HMGCS1 blocked tumor growth in vivo. In conclusion, sevoflurane inhibited colon cancer progression by modulating the exosome-transmitted circ-HMGCS1/miR-34a-5p/SGPP1 axis.

The Liquid Biopsy in the Management of Colorectal Cancer: An Overview

Currently, there is a crucial need for novel diagnostic and prognostic biomarkers with high specificity and sensitivity in patients with colorectal cancer. A "liquid biopsy" is characterized by the isolation of cancer-derived components, such as circulating tumor cells, circulating tumor DNA, microRNAs, long non-coding RNAs, and proteins, from peripheral blood or other body fluids and their genomic or proteomic assessment. The liquid biopsy is a minimally invasive and repeatable technique that could play a significant role in screening and diagnosis, and predict relapse and metastasis, as well as monitoring minimal residual disease and chemotherapy resistance in colorectal cancer patients. However, there are still some practical issues that need to be addressed before liquid biopsy can be widely used in clinical practice. Potential challenges may include low amounts of circulating tumor cells and circulating tumor DNA in samples, lack of pre-analytical and analytical consensus, clinical validation, and regulatory endorsement. The aim of this review was to summarize the current knowledge of the role of liquid biopsy in the management of colorectal cancer.

Effects of miR-135a-5p and miR-141 on proliferation, invasion and apoptosis of colorectal cancer SW620 cells

Effects of miR-135a-5p and miR-141 on the biological function of colorectal cancer SW620 cells were investigated. Fifty-four specimens of cancer tissues and 54 specimens of corresponding adjacent tissues in colon cancer patients who were treated in The Central Hospital of Wuhan from March 2014 to March 2015 were collected. RT-PCR was used to detect the expression levels of miR-135a-5p and miR-141 in cancer tissues and adjacent tissues. The miR-135a-5p inhibitor and miR-141 mimic carriers were established. The cell proliferation was detected by CCK8, the invasion ability of cells in vitro was evaluated by Transwell chamber, and cell apoptosis of each group was detected by flow cytometry. The results of RT-qPCR showed that expression levels of miR-135a-5p in colorectal cancer tissues were significantly higher than those in adjacent tissues, the expression levels of miR-141 in colorectal cancer tissues were significantly lower than those in adjacent tissues, and the difference was statistically significant (P<0.001). The cell survival rates of the miR-135a-5p inhibitor group and the miR-141 mimic group were significantly lower than those of the NC group and the blank group 48 and 72 h after transfection (P<0.001). The number of invasive cells in the miR-135a-5p inhibitor group and the miR-141 mimic group was significantly lower than that in the blank group and the NC group (P<0.001). Apoptosis rate was significantly higher than that of the NC group and the blank group (P<0.001). In conclusion, low expression levels of miR-135a-5p and miR-141 in colorectal adenomas suggested that miR-135a-5p and miR-141 could act as tumor suppressors in the development of colorectal adenomas; miR-135a-5p and miR-141 inhibited the proliferation and invasion of colon cancer SW620 cells and promoted apoptosis of colon cancer cells.

In vitro Biological Tests as the First Tools To Validate Magnetic Nanotheranostics for Colorectal Cancer Models

Colorectal cancer (CRC) remains a leading cause of cancer death. Nanotechnology has focused on reaching more effective treatments. In this concern, magnetic nanoparticles (MNPs) have been studied for a wide range of biomedical applications related to CRC, such as diagnostic imaging, drug delivery and thermal therapy. However, limited research is currently found in the open literature that refers to nanosystems combining all these mentioned areas (theranostics). When developing nanosystems intended as theranostics applied to CRC, possible variations between patients must be considered. Therefore, multiple in vitro assays are required as guidance for future preclinical and clinical trials. The objective of this contribution is to evaluate the available and recent literature regarding the interactions of MNP and CRC models, aiming to critically analyze the information given by the commonly used assays and evaluate the data provided by each one with a view to implementing this novel technology in CRC diagnostics and therapy.

Analysis of the role of the interleukins in colon cancer

Background

The role of interleukin family in colon cancer remained controversial. The purpose of this study was to investigate the association between interleukin family and colon cancer progression through bioinformatics methods and to validate such association in clinical patients.

Methods

A total of 15 differentially expressed interleukins between the colon cancer tissue and normal colon tissue were evaluated from the Cancer Genome Atlas (TCGA) database with R software and only interleukin-7 (IL-7) was significantly associated with survival. The signaling pathway associated with IL-7 was then investigated using gene enrichment analysis. In addition, subsets of TNM were analyzed in detail and univariate and multivariate COX regression analysis were conducted. Finally, we performed western blotting, immunohistochemistry, cell proliferation and cell apoptosis analysis to examine the expression of IL-7 in patients with intestinal cancer.

Results

The study demonstrated that IL-7 could inhibit the progression of colon cancer. In addition, IL-7 was found to be associated with overall survival (OS) and pathological stage. Further analysis of IL-7 expression with clinical data indicated that IL-7 was a key factor in inhibiting colon cancer progression.

Conclusion

IL-7 was a key factor in inhibiting the progression of colon cancer and was closely related to overall survival.

Design and synthesis of new energy restriction mimetic agents: Potent anti-tumor activities of hybrid motifs of aminothiazoles and coumarins

The incidence of obesity-related diseases like diabetes, cardiovascular diseases, and different types of cancers shed light on the importance of dietary control as preventive and treatment measures. However, long-term dietary control is challenging to achieve in most individuals. The use of energy restriction mimetic agents (ERMAs) as an alternative approach to affect the energy machinery of cancer cells has emerged as a promising approach for cancer therapy. ERMAs limit the high need for energy in rapidly growing tumor cells, with their survival rate strongly dependent on the robust availability of energy. In this context, initial phenotypic screening of an in-house pilot compound library identified a new class of aminothiazole anchored on coumarin scaffold as potent anticancer lead drug candidates with potential activity as ERMA. The identified chemotypes were able to inhibit glucose uptake and increase ROS content in cancer cells. Compounds 9b, 9c, 9i, 11b, and 11c were highly active against colorectal cancer cell lines, HCT116 and HT-29, with half-maximal inhibitory concertation (IC₅₀) range from 0.25 to 0.38 µM. Further biological evaluations of 9b and 9f using Western blotting, caspase activity, glucose uptake, ROS production, and NADPH/NADP levels revealed the ability of these lead drug candidates to induce cancer cell death via, at least in part, energy restriction. Moreover, the assessment of 9b and 9f synergistic activity with cisplatin showed promising outcomes. The current work highlights the significant potential of the lead compounds, 9b, and 9f as potential anticancer agents via targeting the cellular energy machinery in cancer cells.

MicroRNA‑3651 promotes colorectal cancer cell proliferation through directly repressing T‑box transcription factor 1

Colorectal cancer is a commonly diagnosed gastrointestinal malignancy worldwide with a high mortality rate. Accumulating evidence has indicated that the expression of a number of microRNAs (miRNAs) is associated with the development of colorectal cancer. However, the precise molecular mechanism of these miRNAs in regulating cancer progression is yet to be determined. In the present study, miR‑3651 was demonstrated to be overexpressed in colorectal cancer tissues compared with normal tissues, and to be associated with the tumor‑node‑metastasis stage. The downregulation of miR‑3651 was found to induce growth arrest and apoptosis in colorectal cancer cells. In addition, western blot analysis demonstrated that the downregulation of miR‑3651 inactivated PI3K/AKT and MAPK/ERK signaling in colorectal cancer cells. Bioinformatics analysis predicted T‑box transcription factor 1 (TBX1) as a potential target gene of miR‑3651, and a dual‑luciferase reporter assay confirmed that TBX1 was directly repressed by miR‑3651. The results of the current study also indicated that TBX1 was associated with the miR‑3651 mediated activation of oncogenic signaling and colorectal cancer cell proliferation. In conclusion, the results of the current study revealed the oncogenic potential of miR‑3651 in colorectal cancer.

Colorectal Cancer Growth Retardation through Induction of Apoptosis, Using an Optimized Synergistic Cocktail of Axitinib, Erlotinib, and Dasatinib

Patients with advanced colorectal cancer (CRC) still depend on chemotherapy regimens that are associated with significant limitations, including resistance and toxicity. The contribution of tyrosine kinase inhibitors (TKIs) to the prolongation of survival in these patients is limited, hampering clinical implementation. It is suggested that an optimal combination of appropriate TKIs can outperform treatment strategies that contain chemotherapy. We have previously identified a strongly synergistic drug combination (SDC), consisting of axitinib, erlotinib, and dasatinib that is active in renal cell carcinoma cells. In this study, we investigated the activity of this SDC in different CRC cell lines (SW620, HT29, and DLD-1) in more detail. SDC treatment significantly and synergistically decreased cell metabolic activity and induced apoptosis. The translation of the in-vitro-based results to in vivo conditions revealed significant CRC tumor growth inhibition, as evaluated in the chicken chorioallantoic membrane (CAM) model. Phosphoproteomics analysis of the tested cell lines revealed expression profiles that explained the observed activity. In conclusion, we demonstrate promising activity of an optimized mixture of axitinib, erlotinib, and dasatinib in CRC cells, and suggest further translational development of this drug mixture.

Differential expression of microRNAs in colorectal cancer: Different patterns between isolated cancer gland and stromal cells

Although microRNAs (miRNAs) play an important role in invasive tumor lesions, which involve cancer tissues mixed with stromal tissues, the differences in miRNA expression between cancer and stromal cells remain unclear. We selected 13 miRNAs and examined their differential expression patterns in cancer gland cells and surrounding stromal cells isolated from 24 colorectal cancer (CRC) specimens using a crypt isolation method. Although six miRNAs were upregulated in gland cells, only three were upregulated in the corresponding stromal cells, in the cancer compared with non-cancer specimens. Next, we examined the differences in miRNA expression between isolated cancer gland and stromal cells. Five miRNAs showed statistical differences in their cancer-related differential expression patterns between isolated cancer gland and stromal cells. We then compared these miRNA expression patterns in isolated cancer gland and stromal cells with those in fresh intact tumor tissues, consisting of cancer nests and stromal tissue, obtained from the 24 CRCs. The expression patterns of three miRNAs in the intact cancer tissue samples did not correspond with those in the isolated components. Identification of the expression patterns of miRNAs in both the cancer gland and stromal cell components of the tumor microenvironment greatly contributes to evaluating epigenetic regulation in CRC.

Expression and Clinical Significance of POLR1D in Colorectal Cancer

PURPOSE

RNA polymerase I subunit D (POLR1D) is involved in the synthesis of ribosomal RNA precursors and small RNAs, but its mechanism in the development and progression of colorectal cancer (CRC) remains ambiguous. Thus, this research aimed to investigate POLR1D's expression and significance in human CRC patients and evaluate its association with clinicopathological characteristics.

METHODS

Matched fresh-frozen cancerous and non-cancerous tissues were collected from 100 patients diagnosed with CRC. Immunohistochemical, Western blot, and quantitative real-time polymerase chain reaction analyses were adopted to validate the correlation between POLR1D expression and clinicopathological parameters in CRC tissues and adjacent normal tissues (ANTs).

RESULTS

POLR1D expression in CRC tissues was significantly higher than in the ANTs. χ2 test and Spearman's correlative analysis showed that a high POLR1D expression is significantly associated with clinical stage, Dukes stage, tumor differentiation, depth of invasion, and metastasis (p < 0.05). It is not correlated with gender, age, and tumor location and size (p > 0.05). Kaplan-Meier survival curves show that the overall survival (OS) time for the low expression group is remarkably longer than for the high expression group (p < 0.0015). Univariate and multivariate analyses indicate that a high POLR1D expression is an independent prognostic factor for poor OS (p = 0.000).

CONCLUSION

The findings of this study strongly indicate that POLR1D plays a pivotal role in the occurrence and progression of CRC. It might be an independent adverse prognostic factor for CRC patients and could serve as a potential therapeutic target for clinical diagnosis in CRC and anticancer drug development.

Tumor heterogeneity: does it matter?

Introduction: It has long been recognized that tumors are composed of a mosaic of cells and numerous methods have been developed to detect tumor heterogeneity, including in situ hybridization, multi-regional sampling, cytological assays, and whole genome and single cell sequencing. Using these methods, heterogeneity has been observed at the genetic, epigenetic, and phenotypic level in numerous cancers. With the advent of deep sequencing technology, we now appreciate a greater complexity of distinct genotypes and phenotypes that drive the biological behavior of cancer. Despite decades of progress in detecting tumor heterogeneity, the question remains: to what extent does it matter? Areas covered: This review explores the evidence for and against the importance of tumor heterogeneity in three main areas: prognostication, development of targeted therapeutics and tumor resistance; summarizing current understanding before evaluating ongoing experimental and clinical developments. Expert opinion: Theoretical understanding and in vitro detection of intratumour heterogeneity promises much but is yet to translate into meaningful clinical benefit. However, the recent emergence of a host of technological innovations and upcoming clinical trials may soon change the landscape of this field.

Identification of new binding proteins of focal adhesion kinase using immunoprecipitation and mass spectrometry

Focal adhesion kinase (FAK) is a 125 kDa protein recruited as a participant in focal adhesion dynamics and serves as a signaling scaffold for the assembly and subsequent maturation of focal contact. Identification of new FAK binding proteins could reveal potential signaling targets and contribute to further development of therapeutic drugs in the treatment of colon cancer. Here, we applied a functional proteomic strategy to identify proteins that interact with FAK in human colon cancer cell line HCT-116. Proteins were targeted by coimmunoprecipitation with an anti-FAK antibody and resolved on 1D-SDS-PAGE. The gel was excised, reduced, alkylated, and trypsin digested. Tryptic peptides were separated by nano-LC-MS/MS by an LTQ-Orbitrap-Velos spectrometer. We identified 101 proteins in the immunocomplex under epithelial growth factor (EGF) stimulation. Three proteins, zyxin, nesprin-1, and desmoplakin, were discovered and validated using reciprocal immunoprecipitation and Western blot analysis. Then, we sought to study the biological relevance of these proteins by siRNA transfection of HCT-116 cells. According to the results, zyxin might play a central role as an upstream regulator to mediate critical cancer-related signaling pathways. Zyxin and nesprin-1 depletion significantly impaired cell migration and invasion capabilities. Additionally, we performed ELISA assays on serum samples from patients with colon cancer instead of cell models to quantify the protein levels of zyxin and nesprin-1. Our results suggested that zyxin and nesprin-1 are not only promising therapeutic targets but also potential diagnostic biomarkers for colon cancer.

Antitumor activity in colorectal cancer induced by hinokiflavone

BACKGROUND AND AIM

Colorectal cancer is one of the most common malignant disease worldwide with highly metastatic potential. Identification of effective therapeutic treatment overcoming such disease is an urgent need. Our study focuses on hinokiflavone as an antitumor agent against colorectal cancer.

METHODS

MTT assay, cell colony formation assay, Hoechst staining, flow cytometry, Western blot analysis, real-time polymerase chain reaction, and migration and invasion assay were performed to identify the effects of hinokiflavone on cell proliferation, apoptosis, and metastasis. CT26 tumor-bearing mice model was conducted to explore the antitumor activity of hinokiflavone in vivo. Immunohistochemistry staining was used to detect the protein expression of Ki-67, cleaved caspase-3, and MMP9 in treated tumors. Acute toxicity was evaluated by serological and hematological analyses, and drug side effect on organs was evaluated by hematoxylin and eosin staining.

RESULTS

Hinokiflavone reduced the proliferation, migration, and invasion and promoted the apoptosis in colorectal tumor cells in vitro. Treatment of hinokiflavone at a tolerable and safe dose (50 mg/kg) significantly suppressed tumor growth in mice bearing CT26 tumors by reducing tumor proliferation and metastasis and inducing apoptosis. Mechanically, treatment of hinokiflavone induced apoptosis by loss of mitochondrial transmembrane potential and increased reactive oxygen species generation.

CONCLUSIONS

Hinokiflavone suppressed colorectal tumor cell proliferation, induced apoptosis via the reactive oxygen species-mitochondria-mediated apoptotic pathway, and inhibited tumor cell migration and invasion. Antitumor activity of hinokiflavone was also validated in mice model without observed toxicity. Our findings suggested that the plant-derived hinokiflavone could be used as an antitumor agent against colorectal cancer.

The identification of CRNDE, H19, UCA1 and HOTAIR as the key lncRNAs involved in oxaliplatin or irinotecan resistance in the chemotherapy of colorectal cancer based on integrative bioinformatics analysis

With the increasing rate of chemoresistance in colorectal cancer (CRC) patients with advanced tumor stages, it is a matter of urgent importance to delineate the factors involved in the drug resistance process. In this study, gene expression profiles were downloaded from the Gene Expression Omnibus database and an integrated analysis with the aim of detecting hub long non‑coding RNAs (lncRNAs) and their regulated, differentially expressed genes (DEGs) during treatment with oxaliplatin (OxPt) or irinotecan was conducted. A total of seven differentially expressed lncRNAs were correlated with OxPt resistance and 21 were correlated with resistance to SN‑38, the active metabolite of irinotecan. Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis confirmed that drug resistance was strongly associated with an imbalance between cell proliferation and apoptosis, cell energetic metabolism under hypoxic conditions, and angiogenesis. Moreover, a large number of lncRNA‑targeted DEGs were located in extracellular exosomes. Further analyses identified four hub lncRNAs involved in the process of drug resistance, including CRNDE, H19, UCA1 and HOTAIR, which are predictive factors for treatment sensitivity. Among them, HOTAIR stands out as a strong factor, the elevated expression of which is also associated with advanced tumor node and metastasis stage and poor CRC disease prognosis.

Up-regulation of microRNA-497-5p inhibits colorectal cancer cell proliferation and invasion via targeting PTPN3

To investigate the role of microRNA-497-5p (miR-497-5p) in the tumorigenesis of colorectal cancer (CRC), the present study applied qRT-PCR to detect the expression level of miR-497-5p in both clinical samples and CRC cell lines. Furthermore, to specifically evaluate the carcinogenic role of miR-497-5p in CRC, the expression of miR-497-5p was monitored by transfecting with the mimics or inhibitors of miR-497-5p. Transwell assay as well as CCK-8 assay were used to determine the functions of miR-497-5p on cell invasion, migration and proliferation, respectively. miR-497-5p expression was remarkably down-regulated in clinical samples with cancer development as well as in CRC cell lines. Additionally, low miR-497-5p expression was remarkably correlated with higher TNM stage and lymph node metastasis of CRC patients. Up-regulation of miR-497-5p significantly inhibited proliferation, migration, and invasion of LOVO CRC cell line. Conversely, antagonizing miR-497-5p significantly promoted cell proliferation, migration and invasion. Mechanistic analysis revealed that miR-497-5p directly bound to its downstream target, protein tyrosine phosphatase non-receptor type 3 (PTPN3), whose aberrant expression partially reversed inhibition of cell proliferation and migration. Taken together, the present study elucidated the inhibitory role of miR-497-5p in CRC via targeting PTPN3, which potentiated miR-497-5p as a potential therapeutic target for combating CRC.

MiR-519b-3p Inhibits the Proliferation and Invasion in Colorectal Cancer via Modulating the uMtCK/Wnt Signaling Pathway

Dysregulation of microRNAs (miRNAs) and their targeted downstream genes is involved in the carcinogenesis and progression of colorectal cancer (CRC). miR-519b-3p has been reported to play an important role in several cancers. However, its function in CRC is unclear. In this study, we detected the expression of miR-519b-3p in CRC tissues and cell lines, and determined the potential role of miR-519b-3p in cell proliferation and invasion in CRC. Also, the downstream gene of miR-519b-3p was determined. Our results showed that miR-519b-3p was notably reduced in CRC specimens and cell lines. Overexpression of miR-519b-3p inhibited the proliferation and invasion of RKO and DLD-1 cells, whereas knockdown of miR-519b-3p had the contrary effect. The ubiquitous mitochondrial creatine kinase (uMtCK) was identified as a direct target of miR-519b-3p in CRC using luciferase assay. Additionally, miR-519b-3p expression was negatively correlated with uMtCK expression in CRC specimens. Notably, the miR-519b-3p suppressed the uMtCK/Wnt signaling pathway in CRC cells, thereby suppressing CRC cell proliferation and invasion. The inhibition of uMtCK by miR-519b-3p may provide a promising option for the treatment of CRC.

An Isoxazole Derivative SHU00238 Suppresses Colorectal Cancer Growth through miRNAs Regulation

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Isoxazoline and isoxazole derivatives represent an important class of five-membered heterocycles, which play a pivotal role in drug discovery. In our previous study, we developed a series of isoxazole derivatives with an efficient method. In this study, we evaluated their effects on tumor cell growth. HCT116 cells were treated with isoxazole derivatives; an cholecystokinin octapeptide (CCK-8) assay was used to calculate the IC₅₀ (half maximal inhibitory concentration) of each derivative. Compound SHU00238, which was obtained by the copper nitrate-mediated [2+2+1] cycloaddition reaction of olefinic azlactone with naphthalene-1,4-dione, has a lower IC₅₀; we analyzed its inhibitory activity in further assays. Cell apoptosis was estimated by flow cytometry analysis in vitro. SHU00238 injection was used to treat tumor-bearing mice. We found that SHU00238 suppressed cell viability and promoted cell apoptosis in vitro. SHU00238 treatment significantly inhibited colonic tumor growth in vivo. Furthermore, we compared the miRNAs expression changes in HCT116 cells before and after SHU00238 treatment. MiRNA profiling revealed that SHU00238 treatment affected cell fate by regulating a set of miRNAs. In conclusion, SHU00238 impedes CRC tumor cell proliferation and promotes cell apoptosis by miRNAs regulation.

Prognostic Nomogram and Patterns of Use of FOLFIRI-Aflibercept in Advanced Colorectal Cancer: A Real-World Data Analysis

INTRODUCTION

The VELOUR study evaluated the efficacy and safety of adding aflibercept to FOLFIRI (fluorouracil, leucovorin, irinotecan) in second-line therapy for metastatic colorectal cancer (mCRC). However, a nomogram that can stratify patients according to prognosis is unavailable, and the frequency and effect of the pragmatic use of modified schedules in actual practice remains unknown.

METHOD

The sample consists of 250 patients with mCRC treated with aflibercept and irinotecan-based chemotherapy at nine Spanish academic centers between January 2013 and September 2015. The result of a Cox proportional hazards model regression for overall survival (OS), adjusted for covariates available in daily practice, was represented as a nomogram and web-based calculator. Harrell's c-index was used to assess discrimination.

RESULTS

The prognostic nomogram for OS includes six variables: Eastern Cooperative Oncology Group performance status, tumor location, number of metastatic sites, mutational status, better response to previous treatment(s), and carcinoembryonic antigen. The model is well calibrated and has acceptable discriminatory capacity (optimism-corrected c-index, 0.723; 95% confidence interval [CI], 0.666-0.778). Median OS was 6.1 months (95% CI, 5.1-8.8), 12.4 months (95% CI, 9.36-14.8), and 22.9 months (95% CI, 16.6-not reached) for high-, intermediate-, and low-risk groups, respectively. Age, comorbidity, or use of modified FOLFIRI regimens did not affect prognosis in this series. Grade 3-4 adverse events were less common following modified schedules. The admission rate because of toxicity was higher in ≥65 years (9.7% vs. 19.6%; odds ratio, 2.26; p = .029).

CONCLUSION

We have developed and internally validated a prognostic model for use in individuals with colorectal cancer initiating therapy with FOLFIRI-aflibercept to predict both OS and the effect of pragmatic modifications of the classic regime on efficacy and safety. This can aid in decision making and in designing future trials.

IMPLICATIONS FOR PRACTICE

In this study, the authors developed and conducted the internal validation of a prognostic nomogram that makes it possible to stratify patients who are eligible for second-line FOLFIRI-aflibercept based on their probability of survival. This model was developed in a multicenter sample from nine Spanish hospitals. Furthermore, to increase the study's validity, the practical use of aflibercept in this setting was investigated, including doses or pragmatic modifications. The results suggest that the modified schedules often used in this daily clinical practice-based patient population are associated with less severe toxicity without apparent detriment to survival endpoints. It is believed that these data complement the information provided by the VELOUR trial and are relevant for the oncologist in treating colon cancer in the second-line setting.

Analysis of risk factors for colon cancer progression

Purpose: This study aimed to find risk factors for colon cancer progression with bioinformatics methods, and validated by clinical patients.

Methods: Differentially expressed genes (DEGs) between colon cancer tissues and normal colon tissues were extracted from The Cancer Genome Atlas (TCGA) database using R software, amounted to 8,051. DEGs between pathologic stage I+II and stage III+IV amounted to 373, and were compared with DEGs of cancer/normal analyzed above to get the intersection of both. Ninety-six intersected DEGs were identified and defined as progressive DEGs of colon cancer. Then these 96 progressive DEGs were studied by Gene ontology and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis using the DAVID database and visualizing by R software. A protein–protein interaction (PPI) network and functional modules were established using the STRING database. Further, an overall survival (OS) curve was drawn via the GEPIA website based on the CGA database and six progressive DEGs were found to be involved with OS of colon cancer patients. The Linkedomics website was used for detailed analysis of specific subsets of TNM.

Results: Pregnancy specific glycoprotein (PSG), vitamin digestion, and absorption were confirmed to promote the progression of colon cancer. Furthermore, NTF4 was found to be associated with both OS and each subset of TNM; therefore, defined as a key risk factor for colon cancer progression. Further analysis of NTF4 expression using clinical data showed it acted as a key risk factor and diagnosis marker for colon cancer progression.

Conclusion: NTF4 is a risk factor contributing to colon cancer progression and associated with overall survival.

Tetrandrine inhibits colon carcinoma HT-29 cells growth via the Bcl-2/Caspase 3/PARP pathway and G1/S phase

Tetrandrine (Tet) bisbenzylisoquinoline alkaloids isolated from Stephania tetrandra and other related species of Menispermaceae. It has been demonstrated to have positive therapeutic effects on cardiovascular disease, hypertension, silicosis, autoimmune diseases. In recent years, some reports have shown that Tet has anticancer activity in human cancers. To explore the pharmacological activity and mechanism of Tet on colon cancer and its unique advantages as a natural product. In the present study, analyses of the cell cycle, apoptosis, targets prediction, molecular docking, and alterations in protein levels were performed to elucidate how Tet functions in colon cancer. We found that Tet robustly induced arrest at the G1 phase in colon cancer cell line HT-29. It induced HT-29 cell apoptosis in a dose-dependent manner. Similarly, analysis of protein expression levels in HT-29 cells showed down-regulation of Bcl-2, pro-caspase 3, pro-caspase 8, PARP, cyclin D1 (CCND1), cyclin-dependent kinase 4 (CDK 4), and up-regulation of Bax, active caspase 3, and active caspase 8. These results indicate that Tet induces apoptosis of colon cancer cells through the mitochondrial pathway and caspase family pathway. Molecular docking showed interaction effects and binding energy. Comparing with the CDK4 inhibitors ribociclib and palbociclib, the docking energy is similar to the docked amino acid residues. Therefore, we conclude that Tet and the CCND1/CDK4 compound could form hydrogen bonds and a stable compound structure, which can inhibit colon cancer cells proliferation by regulating CCND1/CDK4 compound and its downstream proteins phosphorylated Rb (p-Rb). In summary, Tet may be a potential drug for colon cancer therapy.

Design and Synthesis of TASIN Analogues Specifically Targeting Colorectal Cancer Cell Lines with Mutant Adenomatous Polyposis Coli (APC)

Despite advances in targeted anticancer therapies, there are still no small-molecule-based therapies available that specifically target colorectal cancer (CRC) development and progression, the second leading cause of cancer deaths. We previously disclosed the discovery of truncating adenomatous polyposis coli (APC)-selective inhibitor 1 (TASIN-1), a small molecule that specifically targets colorectal cancer cells lines with truncating mutations in the adenomatous polyposis coli (APC) tumor suppressor gene through inhibition of cholesterol biosynthesis. Here, we report a medicinal chemistry evaluation of a collection of TASIN analogues and activity against colon cancer cell lines and an isogenic cell line pair reporting on the status of APC-dependent selectivity. A number of potent and selective analogues were identified, including compounds with good metabolic stability and pharmacokinetic properties. The compounds reported herein represent a first-in-class genotype-selective series that specifically target apc mutations present in the majority of CRC patients and serve as a translational platform toward a targeted therapy for colon cancer.

Value of tumor size as a prognostic factor in metastatic colorectal cancer patients after chemotherapy: a population-based study

Aim: To evaluate the relationship between tumor size and survival in metastatic colorectal cancer (mCRC) patients who received chemotherapy. Materials & methods: SEER database was accessed for eligible patients. Multivariate Cox regression analysis was performed to compare the effect of tumor size on overall survival (OS) and CRC-specific survival (CCSS). Results: Tumor size ≥5 cm was an independent risk factor for OS and CCSS in mCRC patients treated with chemotherapy. Tumor size <5 cm did not show a survival advantage in patients whose primary tumor site was rectosigmoid junction, while tumor size ≥5 cm was associated with poor OS and CCSS in left-and right-sided colorectal cancer. Conclusion: Tumor size ≥5 cm was associated with poor prognosis after receiving chemotherapy treatment and a risk factor for survival of mCRC.

Novel Lysine-Based Thioureas as Mechanism-Based Inhibitors of Sirtuin 2 (SIRT2) with Anticancer Activity in a Colorectal Cancer Murine Model

Sirtuin 2 (SIRT2) is a protein lysine deacylase that has been indicated as a therapeutic target for cancer. To further establish the role of SIRT2 in cancers, it is necessary to develop selective and potent inhibitors. Here, we report the facile synthesis of novel lysine-derived thioureas as mechanism-based SIRT2 inhibitors with anticancer activity. Compounds AF8, AF10, and AF12 selectively inhibited SIRT2 with IC₅₀ values of 0.06, 0.15, and 0.08 μM, respectively. Compounds AF8 and AF10 demonstrated broad cytotoxicity amongst cancer cell lines, but minimal toxicity in noncancerous cells. AF8 and AF10 inhibited the anchorage-independent growth of human colorectal cancer cell line HCT116 with GI₅₀ values of ∼7 μM. Furthermore, AF8 potently inhibited tumor growth in a HCT116 xenograft murine model, supporting that SIRT2 is a viable therapeutic target for colorectal cancer.

Recruiting potent membrane penetrability in tumor cell-targeted protein-only nanoparticles

The membrane pore-forming activities of the antimicrobial peptide GWH1 have been evaluated in combination with the CXCR4-binding properties of the peptide T22, in self-assembling protein nanoparticles with high clinical potential. The resulting materials, of 25 nm in size and with regular morphologies, show a dramatically improved cell penetrability into CXCR4⁺ cells (more than 10-fold) and enhanced endosomal escape (the lysosomal degradation dropping from 90% to 50%), when compared with equivalent protein nanoparticles lacking GWH1. These data reveal that GWH1 retains its potent membrane activity in form of nanostructured protein complexes. On the other hand, the specificity of T22 in the CXCR4 receptor binding is subsequently minimized but, unexpectedly, not abolished by the presence of the antimicrobial peptide. The functional combination T22-GWH1 results in 30% of the nanoparticles entering cells via CXCR4 while also exploiting pore-based uptake. Such functional materials are capable to selectively deliver highly potent cytotoxic drugs upon chemical conjugation, promoting CXCR4-dependent cell death. These data support the further development of GWH1-empowered cell-targeted proteins as nanoscale drug carriers for precision medicines. This is a very promising approach to overcome lysosomal degradation of protein nanostructured materials with therapeutic value.

Gomisin G Suppresses the Growth of Colon Cancer Cells by Attenuation of AKT Phosphorylation and Arrest of Cell Cycle Progression

Colorectal cancer is one of the leading causes of cancer related death due to a poor prognosis. In this study, we investigated the effect of Gomisin G on colon cancer growth and examined the underlying mechanism of action. We found that Gomisin G significantly suppressed the viability and colony formation of LoVo cells. Gomisin G reduced the phosphorylation level of AKT implying that Gomisin G suppressed the PI3K-AKT signaling pathway. Gomisin G also induced apoptosis shown by Annexin V staining and an increased level of cleaved poly-ADP ribose polymerase (PARP) and Caspase-3 proteins. Furthermore, Gomisin G remarkably triggered the accumulation of cells at the sub-G1 phase which represents apoptotic cells. In addition, the level of cyclin D1 and phosphorylated retinoblastoma tumor suppressor protein (Rb) was also reduced by the treatment with Gomisin G thus curtailing cell cycle progression. These findings show the suppressive effect of Gomisin G by inhibiting proliferation and inducing apoptosis in LoVo cells. Taken together, these results suggest Gomisin G could be developed as a potential therapeutic compound against colon cancer.

Bioinformatics Analysis of Key Genes and Pathways in Colorectal Cancer

Colorectal cancer (CRC) is the third most prevalent cancer in the world. Although great progress has been made, the specific molecular mechanism remains unclear. This study aimed to explore the differentially expressed genes (DEGs) and underlying mechanisms of CRC using bioinformatics analysis. In this study, we identified a total of 1353 DEGs in the database of GSE113513, including 715 up- and 638 downregulated genes. Gene ontology analysis results showed that upregulated DEGs were significantly enriched in cell division, cell proliferation, and DNA replication. The downregulated DEGs were enriched in immune response, relation of cell growth and inflammatory response. The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that upregulated DEGs were enriched in cell cycle and p53 signaling pathway, whereas the downregulated DEGs were enriched in drug metabolism, metabolism of xenobiotics by cytochrome P450, and nitrogen metabolism. A total of 124 up-key genes and 35 down-key genes were identified from the protein-protein interaction networks. Furthermore, we identified five up-modules (up-A, up-B, up-C, up-D, and up-E) and three down-modules (d-A, d-B, and d-C) by module analysis. The module up-A was enriched in sister chromatid cohesion, cell division, and mitotic nuclear division. Pathways associated with cell cycle, progesterone-mediated oocyte maturation, oocyte meiosis, and p53 signaling pathway. Whereas the d-A was mainly enriched in G-protein coupled receptor signaling pathway, cell chemotaxis, and chemokine-mediated signaling pathway. The pathways enriched in chemokine signaling pathway, cytokine-cytokine receptor interaction, and alcoholism. These key genes and pathways might be used as molecular targets and diagnostic biomarkers for the treatment of CRC.

Self-antigen MASH2 combined with the AS15 immunostimulant induces tumor protection in colorectal cancer mouse models

Human achaete scute homolog 2 (HASH2) and its murine ortholog MASH2 are potential targets for colorectal cancer immunotherapy. We assessed immunogenicity and antitumor potential of recombinant MASH2 protein combined with AS15 immunostimulant (recMASH2+AS15) in CB6F1 and Apc^+/Min-FCCC mice. CB6F1 mice received 4 injections of recMASH2+AS15 or AS15 alone before challenge with TC1-MASH2 tumor cells (Tumor Challenge). Apc^+/Min-FCCC mice received 9 injections of recMASH2+AS15 or vehicle (phosphate buffer saline [PBS] or AS15 alone), before (two independent Prophylactic Studies) or after (Immunotherapy) colon adenomas were detectable by colonoscopy. CB6F1 mice immunized with recMASH2+AS15 had a significantly smaller mean tumor size and improved survival rate compared to controls (104 mm² vs. 197 mm² [p = 0.009] and 67% vs. 7% [p = 0.001], respectively). In Prophylactic Study 1, the mean number of colon adenomas was significantly lower in Apc^+/Min-FCCC mice receiving recMASH2+AS15 compared to PBS (1.8 [95% confidence interval 1.0–3.3] vs. 5.2 [3.7–7.4], p = 0.003). Fewer microadenomas were observed in recMASH2+AS15 groups compared to PBS in both Prophylactic Studies (Study 1: mean 0.4 [0.2–1.0] vs. 1.5 [0.9–2.4], p = 0.009; Study 2: 0.4 [0.2–0.6] vs. 1.1 [0.8–1.5], p = 0.001). In the Immunotherapy Study, fewer colon adenomas tended to be observed in recMASH2+AS15-treated mice (4.1 [2.9–6.0]) compared to controls (AS15 4.7 [3.3–6.6]; PBS 4.9 [3.5–6.9]; no significant difference). recMASH2+AS15 induced MASH2-specific antibody and CD4+ responses in both mouse models. recMASH2+AS15 partially protected mice against MASH2-expressing tumors and reduced spontaneous colorectal adenomas in Apc^+/Min-FCCC mice, indicating that MASH2/HASH2 antigens are targets for colorectal cancer immunotherapy.