Leucovorin Enhances the Anti-cancer Effect of Bortezomib in Colorectal Cancer Cells

Protective effect of miR-18a in resected liver metastases of colorectal cancer and FOLFOX treatment

BACKGROUND

Colorectal cancer ranks second in terms of cancer associated deaths worldwide, whereas miRNA play a pivotal role in the etiology of cancer and its metastases.

AIMS

Studying the expression and cellular function of miR-18a in metastatic colorectal cancer and association to progression-free survival.

METHODS AND RESULTS

Colorectal liver metastases (N = 123) and primary colorectal cancer (N = 27) where analyzed by RT-PCR and correlated with clinical follow up data. Invasion and migration assays were performed with the liver metastatic cell line LIM2099 after miR-18a knockdown. Cell viability under FOLFOX treatment and knockdown was measured. We found that the expression of miR-18a was increased 4.38-fold in liver metastases and 3.86-fold in colorectal tumor tissue compared to healthy liver tissue and colorectal mucosa, respectively (p ≤ .001). Patients with a high miR-18a expression in liver metastases had a progression-free survival (PFS) of 13.6 months versus 8.9 months in patients with low expression (N = 123; p = .024). In vitro migration of LIM2099 cells was reduced after miR-18a knockdown and cell viability was significantly increased after miR-18a knockdown and treatment with folinic acid or oxaliplatin. Subgroup analysis of PFS revealed significant benefits for patients with high miR-18a expression receiving 5-FU, folinic acid or oxaliplatin.

CONCLUSIONS

High expression of miR-18a in colorectal liver metastases might have a protective effect after resection of metastases and FOLFOX treatment regarding PFS.

Proteasome inhibitors reduce CD73 expression partly via decreasing p-ERK in NSCLC cells

Ecto-5'-nucleotidase (CD73), encoded by the NT5E gene, mediates tumor immunosuppression and has been targeted for the development of new anticancer drugs. Proteasome inhibitors impair protein degradation by inhibiting proteasome and have been used in the clinic for cancer therapy. Here we report that proteasome inhibitors reduce the protein and mRNA levels of CD73. Among 127 tested small-molecule drugs, proteasome inhibitors were found to consistently decrease the protein and mRNA levels of CD73 in NSCLC NCI-H1299 cells. This effect was further confirmed in different NSCLC cells exposed to different proteasome inhibitors. In those treated cells, the protein levels of ERK and its active form p-ERK, the vital components in the MAPK pathway, were reduced. Consistently, inhibitors of MEK and ERK, another two members of the MAPK pathway, also lowered the protein and mRNA levels of CD73. Correspondingly, treatments with fibroblast growth factor 2 (FGF2), an activator of the MAPK pathway, enhanced the levels of p-ERK and partly rescued the proteasome inhibitor-driven reduction of CD73 mRNA and protein in NSCLC cells. However, exogenous CD73 overexpression in murine Lewis lung carcinoma (LLC) cells was not lowered either in vitro or in vivo, by the treatments with proteasome inhibitors and basically, did not affect their in vitro proliferative inhibition either. In contrast, CD73 overexpression dramatically reduced the in vivo anticancer activity of Bortezomib in immunocompetent mice, with tumor growth inhibition rates from 52.18 % for LLC/vector down to 8.75 % for LLC/NT5E homografts. These findings give new insights into the anticancer mechanisms of proteasome inhibitors.

Phosphite-imidazole catalyzed N-formylation and N-acylation of amines

A novel and convenient method for the N-formylation reaction of amines with DMF as a formylating agent has been developed, utilizing a catalytic amount of diethyl phosphite/imidazole. Diethyl phosphite, as a nucleophilic catalyst, plays a significant role in this conversion. The presented method has a broad substrate scope, and various N-formyl products were obtained in good to excellent yields. Moreover, by using DMA instead of DMF, the N-acetylation reaction was also successful. The reaction of o-phenylenediamines with DMF afforded the corresponding benzimidazoles. Furthermore, N-sulfonyl amidines were obtained in good to excellent yields by the reaction of sulfonamides with DMF under similar conditions.

An immune-related gene prognostic index for predicting prognosis in patients with colorectal cancer

Background

Colorectal cancer (CRC) is one of the most common solid malignant burdens worldwide. Cancer immunology and immunotherapy have become fundamental areas in CRC research and treatment. Currently, the method of generating Immune-Related Gene Prognostic Indices (IRGPIs) has been found to predict patient prognosis as an immune-related prognostic biomarker in a variety of tumors. However, their role in patients with CRC remains mostly unknown. Therefore, we aimed to establish an IRGPI for prognosis evaluation in CRC.

Methods

RNA-sequencing data and clinical information of CRC patients were retrieved from The Cancer Genome Atlas (TCGA) and The Gene Expression Omnibus (GEO) databases as training and validation sets, respectively. Immune-related gene data was obtained from the ImmPort and InnateDB databases. The weighted gene co-expression network analysis (WGCNA) was used to identify hub immune-related genes. An IRGPI was then constructed using Cox regression methods. Based on the median risk score of IRGPI, patients could be divided into high-risk and low-risk groups. To further investigate the immunologic differences, Gene set variation analysis (GSVA) studies were conducted. In addition, immune cell infiltration and related functional analysis were used to identify the differential immune cell subsets and related functional pathways.

Results

We identified 49 immune-related genes associated with the prognosis of CRC, 17 of which were selected for an IRGPI. The IRGPI model significantly differentiates the survival rates of CRC patients in the different groups. The IRGPI as an independent prognostic factor significantly correlates with clinico-pathological factors such as age and tumor stage. Furthermore, we developed a nomogram to improve the clinical utility of the IRGPI score. Immuno-correlation analysis in different IRGPI groups revealed distinct immune cell infiltration (CD4⁺ T cells resting memory) and associated pathways (macrophages, Type I IFNs responses, iDCs.), providing new insights into the tumor microenvironment. At last, drug sensitivity analysis revealed that the high-risk IRGPI group was sensitive to 11 and resistant to 15 drugs.

Conclusion

Our study established a promising immune-related risk model for predicting survival in CRC patients. This could help to better understand the correlation between immunity and the prognosis of CRC providing a new perspective for personalized treatment of CRC.

Investigation of the TLR4 and IRF3 signaling pathway-mediated effects of monensin in colorectal cancer cells

Monensin is an ionophore antibiotic isolated from Streptomyces cinnamonensis with very strong antibacterial and antiparasitic effects. Although monensin is known to exhibit anticancer activity in different cancer types, there are a very limited number of studies on its anti-inflammatory effects in colorectal cancer (CRC) cells. The aim of this study was to investigate the TLR4/IRF3-mediated antiproliferative and anti-inflammatory effects of monensin in colorectal cancer cells. The dose- and time-dependent antiproliferative activity of monensin in colorectal cancer cells was determined by XTT method and its effects on mRNA expression changes of Toll-like receptors and IRF3 genes were determined by RT-PCR. TLR4 and Interferon Regulatory Factor 3 (IRF3) protein expression was evaluated by immunofluorescence method. TLR4 and type 1 interferon (IRF) levels were also evaluated by ELISA. IC₅₀ value of monensin in HT29 cells was determined as 10.7082 µM at 48 h and 12.6288 µM at 48th for HCT116 cells. Monensin treatment decreased TLR4 and TLR7 and IRF3 mRNA expression in CRC cells. Monensin treatment decreased the expression level of IRF3 induced by LPS. Our study demonstrates for the first time the TLR4/IRF3-mediated anti-inflammatory effects of monensin in colorectal cancer cells. Further studies on the effects of monensin on TLR receptors in colorectal cancer cells are needed.

Folic Acid and Leucovorin Have Potential to Prevent SARS-CoV-2-Virus Internalization by Interacting with S-Glycoprotein/Neuropilin-1 Receptor Complex

The interaction of the SARS-CoV-2 spike (S) glycoprotein receptor-binding domain with the host-cell ACE2 receptor is a well-known step in virus infection. Neuropilin-1 (NRP-1) is another host factor involved in virus internalization. The interaction between S-glycoprotein and NRP-1 has been identified as a potential COVID-19 treatment target. Herein, the effectiveness of folic acid and leucovorin in preventing contact between S-glycoprotein and NRP-1 receptors was investigated using in silico studies and then confirmed in vitro. The results of a molecular docking study showed that leucovorin and folic acid had lower binding energies than EG01377, a well-known NRP-1 inhibitor, and lopinavir. Two hydrogen bonds with Asp 320 and Asn 300 residues stabilized the leucovorin, while interactions with Gly 318, Thr 349, and Tyr 353 residues stabilized the folic acid. The molecular dynamic simulation revealed that the folic acid and leucovorin created very stable complexes with the NRP-1. The in vitro studies showed that the leucovorin was the most active inhibitor of the S1-glycoprotein/NRP-1 complex formation, with an IC₇₅ value of 185.95 µg/mL. The results of this study suggest that folic acid and leucovorin could be considered as potential inhibitors of the S-glycoprotein/NRP-1 complex and, thus, could prevent the SARS-CoV-2 virus' entry into host cells.

Personalized targeted therapy prescription in colorectal cancer using algorithmic analysis of RNA sequencing data

Background:

Overall survival of advanced colorectal cancer (CRC) patients remains poor, and gene expression analysis could potentially complement detection of clinically relevant mutations to personalize CRC treatments.

Methods:

We performed RNA sequencing of formalin-fixed, paraffin-embedded (FFPE) cancer tissue samples of 23 CRC patients and interpreted the data obtained using bioinformatic method Oncobox for expression-based rating of targeted therapeutics. Oncobox ranks cancer drugs according to the efficiency score calculated using target genes expression and molecular pathway activation data. The patients had primary and metastatic CRC with metastases in liver, peritoneum, brain, adrenal gland, lymph nodes and ovary. Two patients had mutations in NRAS, seven others had mutated KRAS gene. Patients were treated by aflibercept, bevacizumab, bortezomib, cabozantinib, cetuximab, crizotinib, denosumab, panitumumab and regorafenib as monotherapy or in combination with chemotherapy, and information on the success of totally 39 lines of therapy was collected.

Results:

Oncobox drug efficiency score was effective biomarker that could predict treatment outcomes in the experimental cohort (AUC 0.77 for all lines of therapy and 0.91 for the first line after tumor sampling). Separately for bevacizumab, it was effective in the experimental cohort (AUC 0.87) and in 3 independent literature CRC datasets, n = 107 (AUC 0.84–0.94). It also predicted progression-free survival in univariate (Hazard ratio 0.14) and multivariate (Hazard ratio 0.066) analyses. Difference in AUC scores evidences importance of using recent biosamples for the prediction quality.

Conclusion:

Our results suggest that RNA sequencing analysis of tumor FFPE materials may be helpful for personalizing prescriptions of targeted therapeutics in CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10177-3.

Design, synthesis, and biological evaluation of C-8 modified curcumol derivatives against colorectal cancer cell lines

A series of structurally modified curcumol derivatives at C-8 position were designed and synthesized, whose structures were confirmed by 1H NMR,13C NMR, and HRMS analysis. The tested compounds were evaluated for in vitro antitumor activity against colorectal cancer cell lines SW620, HCT116, and CaCo2. Many of the tested candidates exhibited higher inhibition efficiency than curcumol. Among them, compound 3 l shows the best inhibitory effect on the viability of SW620 with IC50 value of 19.90 ± 0.64 µM. The structure-activity relationships of these derivatives were discussed, which showed that the introduction of amino or aryl groups tended to increase the anti-cancer activity. In addition, compound 3 l may inhibit cancer cell proliferation through triggering cell apoptosis.

Proteasome inhibition by bortezomib parallels a reduction in head and neck cancer cells growth, and an increase in tumor-infiltrating immune cells

Head and neck cancer (HNC) has frequently an aggressive course for the development of resistance to standard chemotherapy. Thus, the use of innovative therapeutic drugs is being assessed. Bortezomib is a proteasome inhibitor with anticancer effects. In vitro antitumoral activity of Bortezomib was investigated employing human tongue (SCC-15, CAL-27), pharynx (FaDu), salivary gland (A-253) cancer cell lines and a murine cell line (SALTO-5) originated from a salivary gland adenocarcinoma arising in BALB-neuT male mice transgenic for the oncogene neu. Bortezomib inhibited cell proliferation, triggered apoptosis, modulated the expression and activation of pro-survival signaling transduction pathways proteins activated by ErbB receptors and inhibited proteasome activity in vitro. Intraperitoneal administration of Bortezomib delayed tumor growth of SALTO-5 cells transplanted in BALB-neuT mice, protracted mice survival and adjusted tumor microenvironment by increasing tumor-infiltrating immune cells (CD4⁺ and CD8⁺ T cells, B lymphocytes, macrophages, and Natural Killer cells) and by decreasing vessels density. In addition, Bortezomib modified the expression of proteasome structural subunits in transplanted SALTO-5 cells. Our findings further support the use of Bortezomib for the treatment of HNC and reveal its ineffectiveness in counteracting the activation of deregulated specific signaling pathways in HNC cell lines when resistance to proteasome inhibition is developed.

Nobiletin and Xanthohumol Sensitize Colorectal Cancer Stem Cells to Standard Chemotherapy

Simple Summary

Colorectal cancer stem cells (CR-CSCs) play a pivotal role in the therapy resistance and relapse of CRC patients. Herein we demonstrate that new treatment approaches comprising polymethoxyflavones and prenylflavonoids extracted from Citrus sinensis and Humulus lupulus, respectively, hamper the viability of CR-CSCs as well as synergizing with 5-fluorouracil and oxaliplatin (FOX)-based chemotherapy. Extract fractions containing Nobiletin and Xanthohumol, in combination with chemotherapy, decreased stemness properties of CR-CSCs and restrained the outgrowth of chemoresistant metastatic CR-CSCs. These data pinpoint Nobiletin and Xanthohumol as efficacious anti-cancer compounds in metastatic settings.

Abstract

Colorectal cancer (CRC) mortality is mainly caused by patient refractoriness to common anti-cancer therapies and consequent metastasis formation. Besides, the notorious toxic side effects of chemotherapy are a concurrent obstacle to be tackled. Thus, new treatment approaches are needed to effectively improve patient outcomes. Compelling evidence demonstrated that cancer stem cells (CSCs) are responsible for treatment failure and relapse. New natural treatment approaches showed capabilities to selectively target the CSC subpopulation by rendering them targetable by standard cytotoxic compounds. Herein we show the anti-cancer properties of the polymethoxyflavones and prenylflavonoids extracted from Citrus sinensis and Humulus lupulus, respectively. The natural biofunctional fractions, singularly and in combination, reduced the cell viability of CRC stem cells (CR-CSCs) and synergized with 5-fluorouracil and oxaliplatin (FOX) chemotherapy. These phenomena were accompanied by a reduced S and G2/M phase of the cell cycle and upregulation of cell death-related genes. Notably, both phytoextracts in combination with FOX thwarted stemness features in CR-CSCs as demonstrated by the impaired clonogenic potential and decreased Wnt pathway activation. Extracts lowered the expression of CD44v6 and affected the expansion of metastatic CR-CSCs in patients refractory to chemotherapy. Together, this study highlights the importance of polymethoxyflavones and prenylflavonoids as natural remedies to aid oncological therapies.

A Comprehensive Overview of Colon Cancer- A Grim Reaper of the 21st Century

A few decades ago, the incidence of colorectal cancer (CRC) was low and is now the fourth in the list of deadly cancers producing nearly a million deaths annually. A population that is aging along with risk factors such as smoking, obesity, sedentary lifestyle with little or no physical activity, and non-healthy food habits of developed countries can increase the risk of colorectal cancer. The balance in gut microbiota and the metabolites produced during bacterial fermentation within the host plays a significant role in regulating intestinal diseases as well as colorectal cancer development. Recent progress in the understanding of illness resulted in multiple treatment options such as surgery, radiation, and chemotherapy, including targeted therapy and multitherapies. The treatment plan for CRC depends on the location, stage and grade of cancer as well as genomic biomarker tests. Despite all the advancements made in the genetic and molecular aspects of the disease, the knowledge seems inadequate as the drug action as well as the wide variation in drug response did not appear strongly correlated with the individual molecular and genetic characteristics, which suggests the requirement of comprehensive molecular understanding of this complex heterogeneous disease. Furthermore, multitherapies or a broad spectrum approach, which is an amalgamation of the various promising as well as effective therapeutic strategies that can tackle heterogeneity and act on several targets of the disease, need to be validated in clinical studies. The latest treatment options have significantly increased the survival of up to three years in the case of advanced disease. The fact that colorectal cancer is developed from a polypoid precursor, as well as the symptoms of the disease that occur at an advanced stage, underlines how screening programs can help early detection and decrease mortality as well as morbidity from CRC.

The Protection of Crocin Against Ulcerative Colitis and Colorectal Cancer via Suppression of NF-κB-Mediated Inflammation

Background: In China, the incidence of ulcerative colitis (UC) is increasing every year, but the etiology of UC remains unclear. UC is known to increase the risk of colorectal cancer (CRC). The aim of this study was to investigate the protective effects of crocin against UC and CRC in mouse models.

Methods: Crocin was used to treat the dextran sodium sulfate (DSS)-induced UC mice for 3 weeks, and Apc^MinC/Gpt mice with colorectal cancer for 8 weeks. Proteomics screening was used to detect changes in the protein profiles of colon tissues of UC mice. Enzyme-linked immunosorbent assays and western blot were used to verify these changes.

Results: Crocin strongly reduced the disease activity index scores of UC mice, and improved the pathological symptoms of the colonic epithelium. The anti-inflammatory effects of crocin were indicated by its regulation of the activity of various cytokines, such as interleukins, via the modulation of nuclear factor kappa-B (NF-κB) signaling. Crocin significantly suppressed tumor growth in Apc^MinC/Gpt mice and ameliorated pathological alterations in the colon and liver, but had no effects on spleen and kidney. Additionally, crocin significantly decreased the concentrations of interleukins and tumor necrosis factor-α in the sera and colon tissues, suggesting its anti-inflammatory effects related to NF-κB signaling. Finally, 12-h incubation of SW480 cells with crocin caused cell cycle arrest, enhanced the apoptotic rate, promoted the dissipation of mitochondrial membrane potential, and the over-accumulation of reactive oxygen species. From the theoretical analyses, phosphorylated residues on S536 may enhance the protein-protein interactions which may influence the conformational changes in the secondary structure of NF-κB.

Conclusion: The protective effects of crocin on UC and CRC were due to its suppression of NF-κB-mediated inflammation.

Evaluation of the potency of FDA-approved drugs on wild type and mutant SARS-CoV-2 helicase (Nsp13)

SARS-CoV-2 has caused COVID-19 outbreak with nearly 2 M infected people and over 100K death worldwide, until middle of April 2020. There is no confirmed drug for the treatment of COVID-19 yet. As the disease spread fast and threaten human life, repositioning of FDA approved drugs may provide fast options for treatment. In this aspect, structure-based drug design could be applied as a powerful approach in distinguishing the viral drug target regions from the host. Evaluation of variations in SARS-CoV-2 genome may ease finding specific drug targets in the viral genome. In this study, 3458 SARS-CoV-2 genome sequences isolated from all around the world were analyzed. Incidence of C17747T and A17858G mutations were observed to be much higher than others and they were on Nsp13, a vital enzyme of SARS-CoV-2. Effect of these mutations was evaluated on protein-drug interactions using in silico methods. The most potent drugs were found to interact with the key and neighbor residues of the active site responsible from ATP hydrolysis. As result, cangrelor, fludarabine, folic acid and polydatin were determined to be the most potent drugs which have potency to inhibit both the wild type and mutant SARS-CoV-2 helicase. Clinical data supporting these findings would be important towards overcoming COVID-19.

PAICS, a Purine Nucleotide Metabolic Enzyme, is Involved in Tumor Growth and the Metastasis of Colorectal Cancer

The identification of colorectal cancer (CRC) molecular targets is needed for the development of drugs that improve patient survival. We investigated the functional role of phosphoribosylaminoimidazole carboxylase, phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), a de novo purine biosynthetic enzyme involved in DNA synthesis, in CRC progression and metastasis by using cell and animal models. Its clinical utility was assessed in human CRC samples. The expression of PAICS was regulated by miR-128 and transcriptionally activated by Myc in CRC cells. Increased expression of PAICS was involved in proliferation, migration, growth, and invasion of CRC cells irrespective of the p53 and microsatellite status. In mice, the depletion of PAICS in CRC cells led to reduced tumor growth and metastatic cell dissemination to the liver, lungs, and bone. Positron emission tomography imaging showed significantly reduced metastatic lesions in stable PAICS knockdown CRC cells. In cells with PAICS knockdown, there was upregulation of the epithelial mesenchymal transition marker, E-cadherin, and bromodomain inhibitor, JQ1, can target its increased expression by blocking Myc. PAICS was overexpressed in 70% of CRCs, and was associated with poor 5-year survival independent of the pathologic stage, patient’s race, gender, and age. Overall, the findings point to the usefulness of PAICS targeting in the treatment of aggressive colorectal cancer.

Poly(3-hydroxybutyrate-CO-3-hydroxyvalerate) PHBHV biocompatible nanocarriers for 5-FU delivery targeting colorectal cancer

Aiming to address the issue of poor bioavailability of most anti-tumor medicines against colorectal cancer, we developed a targeted anticancer nanocarrier using biocarriers able to both bind and easily release their load in a controlled manner. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) carriers were obtained via the emulsification-diffusion method, loaded with 5-fluorouracil and then characterized in terms of particle morphology and size (SEM, DLS), drug uptake and release. The cytotoxic potential of the 5-fluorouracil-loaded polymer nanocarriers on human adenocarcinoma cells (HT-29 cell line) was investigated. The in vitro studies clearly demonstrated that while the nanocarriers themselves slightly alter HT-29 cell viability, when loaded with 5-fluorouracil they significantly decrease cell viability, suggesting that the polymer itself exhibits low cytotoxicity and the drug-loaded carrier acts in an efficient manner to kill HT-29 human adenocarcinoma cells.

Synergistic Effects of Bortezomib-OV Therapy and Anti-Invasive Strategies in Glioblastoma: A Mathematical Model

It is well-known that the tumor microenvironment (TME) plays an important role in the regulation of tumor growth and the efficacy of anti-tumor therapies. Recent studies have demonstrated the potential of combination therapies, using oncolytic viruses (OVs) in conjunction with proteosome inhibitors for the treatment of glioblastoma, but the role of the TME in such therapies has not been studied. In this paper, we develop a mathematical model for combination therapies based on the proteosome inhibitor bortezomib and the oncolytic herpes simplex virus (oHSV), with the goal of understanding their roles in bortezomib-induced endoplasmic reticulum (ER) stress, and how the balance between apoptosis and necroptosis is affected by the treatment protocol. We show that the TME plays a significant role in anti-tumor efficacy in OV combination therapy, and illustrate the effect of different spatial patterns of OV injection. The results illustrate a possible phenotypic switch within tumor populations in a given microenvironment, and suggest new anti-invasion therapies.

NF-κB pathways in the development and progression of colorectal cancer

Nuclear factor-κB (NF-κB) has been widely implicated in the development and progression of cancer. In colorectal cancer (CRC), NF-κB has a key role in cancer-related processes such as cell proliferation, apoptosis, angiogenesis, and metastasis. The role of NF-κB in CRC is complex, owed to the cross talk with other signaling pathways. Although there is sufficient evidence gained from cell lines and animal models that NF-κB is involved in cancer-related processes, because of a lack of studies in human tissue, the clinical evidence of its importance is limited in patients with CRC. This review summarizes evidence relating to how NF-κB is involved in the development and progression of CRC and comments on future work to be carried out.