Metformin and ICG-001 Act Synergistically to Abrogate Cancer Stem Cells-Mediated Chemoresistance in Colorectal Cancer by Promoting Apoptosis and Autophagy

Fusobacterium nucleatum modulates the Wnt/β-catenin pathway in colorectal cancer development

The Wnt/β-catenin signalling pathway normally maintains cellular and tissue homeostasis by regulating cellular differentiation and survival in a controlled manner. An aberrantly regulated Wnt/β-catenin signalling pathway can transform into an oncogenic pathway, which is associated with Colorectal cancer (CRC) as well as other cancers. CRC is one of the most frequently occurring gastrointestinal cancers worldwide. In CRC tissues, deregulation of Wnt/β-catenin pathway is observed, which indicates that this oncogenic pathway directly promotes CRC malignancy, cell migration, angiogenesis, chemoresistance, as well as shorter lifespan of a patient. Growing evidence suggests that human commensal microbes have a strong association with carcinogenesis, particularly the prevalence and high enrichment of Fusobacterium nucleatum in CRC progression. The Wnt/β-catenin pathway is one of the targeted pathways by F. nucleatum in CRC, where Fusobacterium adhesin attaches to E-cadherin to initiate infection. Also, Wnt/β-catenin pathway can be a potential target for the treatment of both CRC and F. nucleatum-positive CRC. Here, we discuss the underlying mechanisms of F. nucleatum-positive CRC development through modulation of Wnt/β-catenin signalling and its possibility for the application in targeted therapy of F. nucleatum-positive CRC.

The Role of Reactive Oxygen Species in Colorectal Cancer Initiation and Progression: Perspectives on Theranostic Approaches

Altered levels of reactive oxygen species (ROS) are recognized as one of the key factors in mediating tumor cell survival in the tissue microenvironment, where they play a role in the initiation, progression and recurrence/relapse of colorectal cancer (CRC). Tumor cells can adapt to oxidative stress (OS) using genetic or metabolic reprogramming in the long or short term. In addition, tumor cells defend themselves through positive regulation of antioxidant molecules, enhancing ROS-driven proliferation. Balanced oxidative eustress levels can influence chemotherapy resistance, allowing tumor cells to survive treatment. Secondary effects of chemotherapy include increased ROS production and redox stress, which can kill cancer cells and eliminate drug resistance. Anticancer treatments based on manipulating ROS levels could represent the gold standard in CRC therapy. Therefore, exploring the modulation of the response to OS in deregulated signaling pathways may lead to the development of new personalized CRC treatments to overcome therapy resistance. In this review, we explore the role of ROS in the initiation and progression of CRC and their diagnostic implications as biomarkers of disease. Furthermore, we focused on the involvement of ROS in different CRC therapeutic options, such as surgery, radiotherapy, theranostic imaging, chemotherapy and immunotherapy and other precision medicine approaches.

Evaluation of Anticancer Activity of Novel and Tumor-Targeted Glutamine-Conjugated Organotin(IV) Compounds in Colorectal Cancer─An In Vitro and In Vivo Study

Over the years, numerous ligand-based organotin(IV) Schiff base compounds have shown remarkable cytotoxicity and anticancer activities, but their clinical use is restricted by systemic toxicity, prompting the search for targeted therapies. Targeted delivery can be enhanced by exploiting the inherent characteristics of cancer cells such as glutamine addiction, which is essential to support cellular biosynthesis and cell growth to sustain aberrant proliferation. Our previous study revealed glutamine-conjugated organotin(IV) compounds have strong DNA/protein affinities, favorable in silico ADME profiles, and significant antiproliferative activity. In this study, these compounds demonstrated significant cytotoxicity against human colon carcinoma and adenocarcinoma cell lines via the induction of cell cycle arrest and apoptosis. In DMH/DSS-induced experimental colon carcinogenesis, these compounds reduced tumor burden and volume and inhibited cell proliferation and induced apoptosis, with minimal toxicity. Tissue distribution studies revealed selective accumulation in the colon. These findings support their potential as chemotherapeutic candidates for colon cancer.

Correction: Roy et al. Metformin and ICG-001 Act Synergistically to Abrogate Cancer Stem Cells-Mediated Chemoresistance in Colorectal Cancer by Promoting Apoptosis and Autophagy. Cancers 2022, 14, 1281

In the original publication [...].

Computational Elucidation of Hub Genes and Pathways Correlated with the Development of 5-Fluorouracil Resistance in HCT 116 Colorectal Carcinoma Cell Line

Colorectal cancer (CRC) is the third most deadly cancer diagnosed in both men and women. 5-Fluorouracil (5-FU) treatment frequently causes the CRC cells to become chemoresistance, which has a negative impact on prognosis. Using bioinformatic techniques, this work describes important genes and biological pathways linked to 5-FU resistance in CRC cells. In our studies, a 5-FU-resistant HCT 116 cell line exhibiting elevated TYMS was created and validated using various tests. Bioinformatic studies were conducted to determine which differentially expressed genes (DEGs) were responsible for the establishment of 5-FU resistance in the same cell line. After screening 3949 DEGs from the two public datasets (GSE196900 and GSE153412), 471 overlapping DEGs in 5-FU-resistant HCT 116 cells were chosen. These overlapping DEGs were used to build the PPI network, and a major cluster module containing 21 genes was found. Subsequently, using three topological analysis algorithms, 10 hub genes were identified, which included HLA-DRA, HLA-DRB1, CXCR4, MMP9, CDH1, SMAD3, VIM, SYK, ZEB1, and SELL. Their roles were ascertained by utilizing Gene Ontology keywords and pathway enrichment studies. Our results also demonstrated that the miRNA and transcription factors (TFs) that had the strongest connection with the hub genes were hsa-mir-26a-5p, hsa-mir-30a-5p, RELA, and NFKB1. Ultimately, 84 FDA-approved drugs that target those hub genes were found to potentially treat 5-FU resistance CRC. Our research's findings increase our understanding of the fundamental factors that contribute to the prevalence of 5-FU resistance CRC, which could ultimately assist in the identification of valuable malignancy biomarkers and targeted treatment approaches based on key regulatory pathways.

The anticancer effects of Aronia berry extract are mediated by Chk1 and p53 in colorectal cancer

BACKGROUND

Aronia berry extracts (ABE) have recently been reported to possess significant anti-cancer effects in various malignancies, including colorectal cancer (CRC), due to their high polyphenolic content. However, the molecular mechanism(s) underlying the anti-cancer effects of ABE in CRC remain unclear, which is important to consider when considering their use as complementary medicine approaches in cancer.

METHODS

We performed genome-wide transcriptomic profiling and pathway enrichment analysis to identify specific growth signaling pathways associated with ABE treatment in CRC cells. In addition, a series of systematic and comprehensive cell culture studies were performed to investigate the anti-cancer effects of ABE in SW480 and HCT116 CRC cell lines. Subsequently, these findings were validated in patient-derived 3D organoids (PDOs) models.

RESULTS

Transcriptomic profiling analysis identified p53 signaling as one of the key enriched pathways mediating the anti-cancer activity of ABE. Analysis of public datasets revealed that Chk1, a key regulator of p53, was one of the critical targets of ABE in CRC. Chk1 and p53 activation was shown to be downregulated with ABE treatment, leading to the induction of cell cycle arrest (p = 0.003-0.014) and enhanced DNA damage (p = 0.015-0.026). Furthermore, these findings were validated in PDOs, where the ABE treatment resulted in significantly fewer and smaller PDOs in a concentration-dependent manner (p = 0.045 - <0.001).

CONCLUSIONS

We firstly provide evidence for the role of the p53 signaling pathway as a mediator of the anti-cancer activity of ABE, which provides a rationale for its use as a safe and effective integrative medicine approach in CRC.

Integrated analysis reveals a novel 5-fluorouracil resistance-based prognostic signature with promising implications for predicting the efficacy of chemotherapy and immunotherapy in patients with colorectal cancer

BACKGROUND

5-Fluorouracil (5-FU) has been used as a standard first-line treatment for colorectal cancer (CRC) patients. Although 5-FU-based chemotherapy and immune checkpoint blockade (ICB) have achieved success in treating CRC, drug resistance and low response rates remain substantial limitations. Thus, it is necessary to construct a 5-FU resistance-related signature (5-FRSig) to predict patient prognosis and identify ideal patients for chemotherapy and immunotherapy.

METHODS

Using bulk and single-cell RNA sequencing data, we established and validated a novel 5-FRSig model using stepwise regression and multiple CRC cohorts and evaluated its associations with the prognosis, clinical features, immune status, immunotherapy, neoadjuvant therapy, and drug sensitivity of CRC patients through various bioinformatics algorithms. Unsupervised consensus clustering was performed to categorize the 5-FU resistance-related molecular subtypes of CRC. The expression levels of 5-FRSig, immune checkpoints, and immunoregulators were determined using quantitative real-time polymerase chain reaction (RT‒qPCR). Potential small-molecule agents were identified via Connectivity Map (CMap) and molecular docking.

RESULTS

The 5-FRSig and cluster were confirmed as independent prognostic factors in CRC, as patients in the low-risk group and Cluster 1 had a better prognosis. Notably, 5-FRSig was significantly associated with 5-FU sensitivity, chemotherapy response, immune cell infiltration, immunoreactivity phenotype, immunotherapy efficiency, and drug selection. We predicted 10 potential compounds that bind to the core targets of 5-FRSig with the highest affinity.

CONCLUSION

We developed a valid 5-FRSig to predict the prognosis, chemotherapeutic response, and immune status of CRC patients, thus optimizing the therapeutic benefits of chemotherapy combined with immunotherapy, which can facilitate the development of personalized treatments and novel molecular targeted therapies for patients with CRC.

The Impact of Cancer Stem Cells in Colorectal Cancer

Despite incessant research, colorectal cancer (CRC) is still one of the most common causes of fatality in both men and women worldwide. Over time, advancements in medical treatments have notably enhanced the survival rates of patients with colorectal cancer. Managing metastatic CRC involves a complex tradeoff between the potential benefits and adverse effects of treatment, considering factors like disease progression, treatment toxicity, drug resistance, and the overall impact on the patient's quality of life. An increasing body of evidence highlights the significance of the cancer stem cell (CSC) concept, proposing that CSCs occupy a central role in triggering cancer. CSCs have been a focal point of extensive research in a variety of cancer types, including CRC. Colorectal cancer stem cells (CCSCs) play a crucial role in tumor initiation, metastasis, and therapy resistance, making them potential treatment targets. Various methods exist for isolating CCSCs, and understanding the mechanisms of drug resistance associated with them is crucial. This paper offers an overview of the current body of research pertaining to the comprehension of CSCs in colorectal cancer.

The potential therapeutic effect of melatonin in oxaliplatin combination therapy against chemoresistant colorectal cancer cells

BACKGROUND

Oxaliplatin is one of the main therapeutics in colorectal cancer (CRC) chemotherapy. However, in light of multidrug resistance (MDR) phenotype development, the efficacy of oxaliplatin has decreased. This study aimed to assess the potential therapeutic effect of melatonin in oxaliplatin combination therapy for drug-resistant colorectal cancer cells.

METHODS AND RESULTS

Initially, the oxaliplatin-resistant cell line was created of LS174T (LS174T/DR) by using the oxaliplatin IC50 concentration and resting cycles. MTT assays and flow cytometry were applied for assessing cell viability and apoptotic cells. The mRNA expression level of Bax, Bcl2, MT1, MT2, and ABCB1 as well as protein levels of ABCB1, Bcl2, BAX were measured by the qRT-PCR and western blot techniques respectively. P-gp activity was assessed by Rho123 staining. The IC50 concentration of oxaliplatin in resistant cells was increased from 500.7 ± 0.2 nM to 7119 ± 0.1 nM. Bcl2, MT1, MT2, and ABCB1 mRNA plus protein expression levels of Bcl2 and ABCB1 were significantly reduced in resistant cells, along with a marked increase in Bax mRNA and protein levels compared to parental cells. Rho 123 staining revealed a marked reduction in P-gp activities in the combination-treated group compared to the oxaliplatin-treated group.

CONCLUSIONS

The results of cytotoxicity assays, MTT, and flow cytometry revealed that the combination of melatonin and oxaliplatin exerts synergistic effects on induction of oxaliplatin's cytotoxicity in CRC. Our research suggests that combining the treatments of melatonin and oxaliplatin may be considered as a new approach to overcoming oxaliplatin resistance in CRC patients.

Colorectal Cancer Stem Cells and Targeted Agents

Since their discovery, cancer stem cells have become a hot topic in cancer therapy research. These cells possess stem cell-like self-renewal and differentiation capacities and are important factors that dominate cancer metastasis, therapy-resistance and recurrence. Worse, their inherent characteristics make them difficult to eliminate. Colorectal cancer is the third-most common cancer and the second leading cause of cancer death worldwide. Targeting colorectal cancer stem cells (CR-CSCs) can inhibit colorectal cancer metastasis, enhance therapeutic efficacy and reduce recurrence. Here, we introduced the origin, biomarker proteins, identification, cultivation and research techniques of CR-CSCs, and we summarized the signaling pathways that regulate the stemness of CR-CSCs, such as Wnt, JAK/STAT3, Notch and Hh signaling pathway. In addition to these, we also reviewed recent anti-CR-CSC drugs targeting signaling pathways, biomarkers and other regulators. These will help researchers gain insight into the current agents targeting to CR-CSCs, explore new cancer drugs and propose potential therapies.

Autophagy/ferroptosis in colorectal cancer: Carcinogenic view and nanoparticle-mediated cell death regulation

The cell death mechanisms have a long history of being evaluated in diseases and pathological events. The ability of triggering cell death is considered to be a promising strategy in cancer therapy, but some mechanisms have dual functions in cancer, requiring more elucidation of underlying factors. Colorectal cancer (CRC) is a disease and malignant condition of colon and rectal that causes high mortality and morbidity. The autophagy targeting in CRC is therapeutic importance and this cell death mechanism can interact with apoptosis in inhibiting or increasing apoptosis. Autophagy has interaction with ferroptosis as another cell death pathway in CRC and can accelerate ferroptosis in suppressing growth and invasion. The dysregulation of autophagy affects the drug resistance in CRC and pro-survival autophagy can induce drug resistance. Therefore, inhibition of protective autophagy enhances chemosensitivity in CRC cells. Moreover, autophagy displays interaction with metastasis and EMT as a potent regulator of invasion in CRC cells. The same is true for ferroptosis, but the difference is that function of ferroptosis is determined and it can reduce viability. The lack of ferroptosis can cause development of chemoresistance in CRC cells and this cell death mechanism is regulated by various pathways and mechanisms that autophagy is among them. Therefore, current review paper provides a state-of-art analysis of autophagy, ferroptosis and their crosstalk in CRC. The nanoparticle-mediated regulation of cell death mechanisms in CRC causes changes in progression. The stimulation of ferroptosis and control of autophagy (induction or inhibition) by nanoparticles can impair CRC progression. The engineering part of nanoparticle synthesis to control autophagy and ferroptosis in CRC still requires more attention.

Research Progress of Metformin in the Treatment of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies and has a high mortality, posing a great threat to both human physical and mental health. With the advancement of scientific research, a variety of cancer therapies have been used for OSCC treatment. However, the prognosis of OSCC shows no significant improvement. Metformin has been recognized as the first-line drug for the treatment of diabetes, and recent studies have shown that metformin has a remarkable suppressive effect on tumor progression. Metformin can not only affect the energy metabolism of tumor cells but also play an antitumor role by modulating the tumor microenvironment and cancer stem cells. In this review, the molecular mechanism of metformin and its anticancer mechanism in OSCC are summarized. In addition, this article summarizes the side effects of metformin and the future prospects of its application in the treatment of OSCC.

Autophagy as a self-digestion signal in human cancers: Regulation by microRNAs in affecting carcinogenesis and therapy response

Autophagy is defined as a "self-digestion" signal, and it is a cell death mechanism its primary function is degrading toxic agents and aged organelles to ensure homeostasis in cells. The basic leve ls of autophagy are found in cells, and when its levels exceed to standard threshold, cell death induction is observed. Autophagy dysregulation in cancer has been well-documented, and regulation of this pathway by epigenetic factors, especially microRNAs (miRNAs), is interesting and noteworthy. miRNAs are considered short endogenous RNAs that do not encode functional proteins, and they are essential regulators of cell death pathways such as apoptosis, necroptosis, and autophagy. Accumulating data has revealed miRNA dysregulation (upregulation or downregulation) during tumor progression, and their therapeutic manipulation provides new insight into cancer therapy. miRNA/autophagy axis in human cancers has been investigated an exciting point is the dual function of both autophagy and miRNAs as oncogenic and onco-suppressor factors. The stimulation of pro-survival autophagy by miRNAs can increase the survival rate of tumor cells and mediates cancer metastasis via EMT inductionFurthermore, pro-death autophagy induction by miRNAs has a negative impact on the viability of tumor cells and decreases their survival rate. The miRNA/autophagy axis functions beyond regulating the growth and invasion of tumor cells, and they can also affect drug resistance and radio-resistance. These subjects are covered in the current review regarding the new updates provided by recent experiments.

Curcumin-Mediated Resistance to Lenvatinib via EGFR Signaling Pathway in Hepatocellular Carcinoma

Lenvatinib is a multi-kinase inhibitor approved as a first-line treatment for patients with unresectable advanced hepatocellular carcinoma (HCC). However, its response rate is unsatisfactory, primarily due to the acquisition of resistance, which limits its clinical significance for treating patients with HCC. Recent evidence suggests that epidermal growth factor receptor (EGFR) activation can trigger Lenvatinib-resistance; and is considered an important therapeutic target in HCC. Curcumin, one of the most studied naturally occurring botanicals with robust anti-cancer activity, is also reported to be a potent tyrosine kinase inhibitor. In this study, we hypothesized that the anti-EGFR potential of Curcumin might help overcome Lenvatinib resistance in HCC. We established two Lenvatinib-resistant cells and discovered that a combination of Curcumin and Lenvatinib exhibited a synergistic anti-tumor efficacy in the resistant HCC cell lines. In line with previous reports, Lenvatinib-resistant cell lines revealed significant activation of the EGFR, and genomewide transcriptomic profiling analysis identified that the PI3K-AKT pathway was associated with Lenvatinib resistance. The combination treatment with Curcumin and Lenvatinib dramatically suppressed gene and protein expression of the EGFR-PI3K-AKT pathway, suggesting Curcumin overcomes Lenvatinib resistance via inhibition of EGFR. We further validated these findings in tumor spheroids derived from resistant cell lines. In conclusion, we, for the first time, report that Curcumin reverses Lenvatinib resistance in HCC, and that their combination has clinical application potential for adjunctive treatment in HCC.

Andrographis Reverses Gemcitabine Resistance through Regulation of ERBB3 and Calcium Signaling Pathway in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, primarily due to intrinsic or acquired resistance to chemotherapy, such as Gemcitabine (Gem). Naturally occurring botanicals, including Andrographis (Andro), can help enhance the anti-tumorigenic therapeutic efficacy of conventional chemotherapy through time-tested safety and cost-effectiveness. Accordingly, we hypothesized that Andro might reverse Gem resistance in PDAC. The critical regulatory pathways associated with Gem resistance in PDAC were identified by analyzing publicly available transcriptomic profiling and PDAC tissue specimens. A series of systematic in vitro experiments were performed using Gem-resistant (Gem-R) PDAC cells and patient-derived 3D-organoids to evaluate the Andro-mediated reversal of Gem resistance in PDAC. Transcriptomic profiling identified the calcium signaling pathway as a critical regulator of Gem-resistance (Fold enrichment: 2.8, p = 0.002). Within this pathway, high ERBB3 expression was significantly associated with poor prognosis in PDAC patients. The combination of Andro and Gem exhibited superior anti-cancer potential in Gem-R PDAC cells through potentiating cellular apoptosis. The combined treatment down-regulated ERBB3 and decreased intracellular calcium concentration in Gem-R PDAC cells. Finally, these findings were successfully interrogated in patient-derived 3D-organoids. In conclusion, we demonstrate novel evidence for Andro-mediated reversal of chemoresistance to Gem in PDAC cells through the regulation of ERBB3 and calcium signaling.

Metformin Suppresses Hepatocellular Carcinoma through Regulating Alternative Splicing of LGR4

METHODS

First, the expression of LGR4 in HCC tumor tissues and cell lines was detected by western blotting and immunofluorescence. The ability of cell proliferation, migration, and invasion was detected with CCK8, wound-healing, and transwell assays when overexpressing LGR4 or treating with metformin. The β-catenin expression was detected by immunofluorescence. In order to investigate novel AS-associated LGR4, we discarded LGR4 isoforms from GSO databases. We used siRNA to knock down the specific isoform to check the cell proliferation, migration, and invasion when treated with metformin.

RESULTS

The level of LGR4 expression was higher in HCC cell lines and tumor tissues. The HCC cell proliferation, migration, and invasion were increased when overexpressing LGR4, which could be reduced by metformin treatment. The GEO database (GSE190076) showed that LGR4 had switching properties in HCC cell lines treated with metformin. We used siRNA to knock down the specific isoform, and the result showed that the specific isoform siRNA could promote the inhibition of cell invasion caused by metformin treatment.

CONCLUSIONS

LGR4 could promote the ability of cell proliferation, migration, and invasion in HCC, which could be reduced by metformin through alternative splicing.