The novel anthraquinone derivative IMP1338 induces death of human cancer cells by p53-independent S and G2/M cell cycle arrest

Aloe-Emodin Isolated from Rheum Undulatum L. Regulates Cell Cycle Distribution and Cellular Senescence in Human Prostate Cancer LNCaP Cells

Senescence can promote hyperplastic pathologies, such as cancer. Prostate cancer is the second most common type of cancer in men. The p21-mediate cellular senescence, facilitated through the tumor suppressor p53-dependent pathway, is considered the primary mechanism for cancer treatment. Aloe-emodin, has been reported to exert anticancer effects in various types of cancers. This study aimed to investigate the bioactivity of aloe-emodin in LNCaP cells via the activation of p21-mediated cellular senescence. Aloe-emodin treatment increased the percentage of cells in the G1 phase while decreasing the percentage in the S phase. This effect was reflected in the expression levels of proteins associated with cell cycle progression, such as p21CIP, retinoblastoma protein, and cyclin-dependent kinase2/4 in LNCaP cells. However, aloe-emodin-treated LNCaP cells did not induce cell cycle arrest at G2/M checkpoint. Moreover, increased senescence-associated-galactosidase activity was observed in a dose-dependent manner following treatment with aloe-emodin. Aloe-emodin also induced DNA damage by modulating the expression of histone H2AX and lamin B1. Furthermore, aloe-emodin inhibited the proliferation of LNCaP cells, contrasting with the exponential growth observed in the nontreated cells. Importantly, this inhibition did not impact the immune system, as evidenced by the increased proliferation of splenocytes isolated from mice. These findings provide preliminary evidence of the anticancer effect of aloe-emodin in LNCaP cells, necessitating further investigations into the underlying mechanisms in vivo and human subjects.

Visible light enabled [4+2] annulation reactions for anthracenone-furans from 2,3-dibromonaphthoquinone and phenylbenzofurans

A facile visible light promoted approach to anthracenone-furans from readily available 2,3-dibromonaphthoquinones and phenylbenzofurans via a formal Diels Alder reaction is reported. This reaction involves wavelength-selective agitation of 4CzIPN, energy transfer to quinones, recombination of 1,6-biradicals and elimination to give anthracenone-furans in good to excellent yields in one pot.

Journey of anthraquinones as anticancer agents - a systematic review of recent literature

Anthraquinones are privileged chemical scaffolds that have been used for centuries in various therapeutic applications. The anthraquinone moiety forms the core of various anticancer agents. However, the emergence of drug-resistant cancers warrants the development of new anticancer agents. The research endeavours towards new anthraquinone-based compounds are increasing rapidly in recent years. They are used as a core chemical template to achieve structural modifications, resulting in the development of new anthraquinone-based compounds as promising anticancer agents. Mechanistically, most of the anthraquinone-based compounds inhibit cancer progression by targeting essential cellular proteins. Herein, we review new anthraquinone analogues that have been developed in recent years as anticancer agents. This includes a systematic review of the recent literature (2005-2021) on anthraquinone-based compounds in cell-based models and key target proteins such as kinases, topoisomerases, telomerases, matrix metalloproteinases and G-quadruplexes involved in the viability of cancer cells. In addition to this, the developments in PEG-based delivery of anthraquinones and the toxicity aspects of anthraquinone derivatives are also discussed. The review dispenses a compact background knowledge to understanding anthraquinones for future research on the expansion of anticancer therapeutics.

Knockdown of POLQ interferes the development and progression of hepatocellular carcinoma through regulating cell proliferation, apoptosis and migration

Background

DNA Polymerase Theta (POLQ) is a DNA polymerase involved in error-prone translesion DNA synthesis (TLS) and error-prone repair of DNA double-strand breaks (DSBs), whose function in hepatocellular carcinoma has not been investigated.

Methods

In the present study, both the data collected from the Cancer Genome Atlas (TCGA) and our group’s results showed higher POLQ expression in HCC tissues than the para-cancerous tissues, which was associated with higher malignancy and poor prognosis. POLQ knockdown HCC cell model (shPOLQ) was constructed along with the corresponding negative control (shCtrl) through lentivirus infection for loss-of-function study.

Results

We found that, upon knockdown of POLQ, the proliferation and migration of HCC cells decreased and apoptosis percentage increased. Moreover, the percentage of cells in G2 phase significantly increased in shPOLQ group compared with shCtrl group. Xenografts in mice grafted with shPOLQ cells grew much slower than that transplanted with shCtrl cells, and expressed lower Ki67 level. Furthermore, an apoptosis-related signaling array was used to explore the involvement of downstream signaling pathways, suggesting the enhanced phosphorylation of HSP27 and JNK, and the de-activation of mTOR, PRAS40, ERK1/2 and STAT3 pathways.

Conclusions

Collectively, our study revealed that POLQ may participate in the development of HCC, depletion of which may be a promising treatment strategy for HCC.

Aloe and its Effects on Cancer: A Narrative Literature Review

Many years ago, Aloe Vera was cited to have a lot of therapeutic properties including; anti-microbial, anti-viral, anti-cancer, anti-oxidant, anti-inflammatory, skin protection, wound healing, and regulation of blood glucose and cholesterol. However, Aloe could present some side effects. This review focused on the latest discoveries regarding the therapeutic role of Aloe plant or its compounds on the acquired biological capabilities for tumour growth and progression namely; evading growth suppressor, avoiding immune destruction, enabling replicative immortality, tumour promoting inflammation, activating invasion and metastasis, inducing angiogenesis, genome instability and mutation, resisting cell death, deregulating cellular energetics and sustaining proliferating signalling. It clarified the anti-cancer activities it exerts on different types of cancer and also highlighted some pro-oncogenic pathways that can be disrupted by different compounds of Aloe.

Preparation of novel anthraquinone-based aspirin derivatives with anti-cancer activity

Gastric cancer is one of the most common and deadly cancers among men and women and is the third leading cause of cancer mortality worldwide. Thus, discovering and developing novel therapeutics for gastric cancer has become a global priority. In this study, we synthesized two novel anthraquinone-based aspirin derivatives, Asp-X₃ and Asp-X₃-CH₃, with therapeutic potential for gastric cancer. The structures of the two compounds were determined by 1D, 2D-NMR, and High-Resolution Mass (HRSM). Asp-X₃ and Asp-X₃-CH₃ could inhibit the growth of gastric cancer cells (SGC7901), yielding IC₅₀ values 10-fold lower than that of Aspirin. Asp-X₃ and Asp-X₃-CH₃ were less toxic to gastric mucosal cells, yielding IC₅₀ values that were about 2-fold higher than the corresponding IC₅₀ values determined with SGC7901 cells. Asp-X₃-CH₃ and Asp-X₃ also induced SGC7901 cells to undergo apoptosis, yielding apoptotic rates that were about twice the rate induced by Aspirin. Asp-X₃-CH₃ did not cause significant loss of COX-1 expression in gastric mucosal cells, whereas Asp-X₃ and Aspirin both caused significant loss of COX-1 expression as demonstrated by Western blot, consistent with their effects on the content of PGE₂ in these cells as determined by ELISA assay. However, both Asp-X₃-CH₃ and Asp-X₃ exerted a similar effect on the level of COX-2 in gastric cancer cells, causing as much as 90% and 95% reduction in COX-2 expression, respectively. Taken together, the results suggested that Asp-X₃-CH₃ and Asp-X₃ were potentially better agents than Aspirin for the inhibition of gastric cancer cell growth, but Asp-X₃-CH₃ was more effective.

Anthraquinone derivative C10 inhibits proliferation and cell cycle progression in colon cancer cells via the Jak2/Stat3 signaling pathway

Since its discovery, anthraquinone has become very valuable as a lead compound in the development of anti-cancer drugs. Previously, we designed and synthesized a new type of amide anthraquinone derivative (1-nitro-2-acylanthraquinone glycine, C10) with good activity against colon cancer. However, its effect and the underlying mechanism are unclear. In this study, C10 significantly inhibited the proliferation of HCT116 and HT29 colon cancer cells by blocking the cell cycle at the G2/M phase. C10 also plays a role in cell cycle arrest by reducing the protein and gene expression levels of cyclin B1 and its downstream signaling molecule cyclin-dependent kinase (CDK1). In addition, molecular docking studies showed that C10 has high affinity for Jak2, the first target in the cell cycle-related Jak2/Stat3 signaling pathway. Furthermore, C10 downregulated the expression of Jak2/Stat3 signaling pathway-related signaling molecules proteins and genes, and up-regulated the expression of PIAS-3, the upstream signaling molecule of Stat3, thereby down-regulating Stat3 phosphorylation. C10 reversed the expression of Jak2/Stat3 signaling pathway-related molecules activated by IL-6. Overall, our results indicate for the first time that C10 induces cell cycle arrest and inhibits cell proliferation by inhibiting the Jak2/Stat3 signaling pathway. This study provides new insights into the potential role of Jak2/Stat3 in the regulating cell cycle-related signaling pathways that mediate the inhibitory effects of C10 on colon cancer cell proliferation.

Derivatives of Deoxypodophyllotoxin Induce Apoptosis through Bcl-2/Bax Proteins Expression

BACKGROUND

Deoxypodophyllotoxin, isolated from the Traditional Chinese Medicine Anthriscus sylvestris, is well-known because of its significant anti-tumor activity with strong toxicity in vitro and in vivo.

OBJECTIVE

In this article, a series of deoxypodophyllotoxin derivatives were synthesized and their anti-tumor effectiveness was evaluated.

METHODS

The anti-tumor activity of deoxypodophyllotoxin derivatives was investigated by the MTT assay method. Apoptosis percentage was measured by flow cytometer analysis using Annexin-V-FITC.

RESULTS

The derivatives revealed obvious cytotoxicity in the MTT assay by decreasing the number of late cancer cells. The decrease of Bcl-2/Bax could be observed in MCF-7, HepG2, HT-29, and MG-63 using Annexin V-FITC. The ratio of Bcl-2/Bax in the administration group was decreased, which was determined by the ELISA kit.

CONCLUSION

The derivatives of deoxypodophyllotoxin could induce apoptosis in tumor cell lines by influencing Bcl-2/Bax.

Anthraquinone: a promising scaffold for the discovery and development of therapeutic agents in cancer therapy

Cancer, characterized by uncontrolled malignant neoplasm, is a leading cause of death in both advanced and emerging countries. Although, ample drugs are accessible in the market to intervene with tumor progression, none are totally effective and safe. Natural anthraquinone (AQ) equivalents such as emodin, aloe-emodin, alchemix and many synthetic analogs extend their antitumor activity on different targets including telomerase, topoisomerases, kinases, matrix metalloproteinases, DNA and different phases of cell lines. Nano drug delivery strategies are advanced tools which deliver drugs into tumor cells with minimum drug leakage to normal cells. This review delineates the way AQ derivatives are binding on these targets by abolishing tumor cells to produce anticancer activity and purview of nanoformulations related to AQ analogs.

Sodium fluoride causes hepatocellular S-phase arrest by activating ATM-p53-p21 and ATR-Chk1-Cdc25A pathways in mice

In this study, experimental pathology, flow cytometry (FCM), quantitative real-time polymerase chain reaction (qRT-PCR), and western blot (WB) were used to evaluate the effects of sodium fluoride (NaF) on hepatocellular cell cycle progression in mice. A total of 240 ICR mice were divided equally into four groups; the experimental groups received 12, 24, or 48 mg/kg NaF intragastrically for 42 days, while the control group received distilled water. Doses of NaF above 12 mg/kg increased the percentage of cells in S phase (S-phase arrest), reduced percentages of cells in G0/G1 or G2/M phase, and activated the ATM-p53-p21 and ATR-Chk1-Cdc25A pathways. Activation of these pathways was characterized by up-regulation of ATM, p53, p21, ATR, and Chk1 mRNA and protein expression, and down-regulation of Cdc25A, cyclin E, cyclin A, CDK2, CDK4, and proliferating cell nuclear antigen (PCNA) mRNA and protein expression. These results indicate that NaF caused S-phase arrest by activating the ATM-p53-p21 and ATR-Chk1-Cdc25A pathways.

Efficient and selective iron-mediated reductive Claisen rearrangement of propargyloxyanthraquinones to anthrafurandiones in ionic liquids

An efficient and rapid method is described for the reductive Claisen rearrangement of different propargyloxyanthraquinones to anthra[1,2-b]furan-6,11-diones for first time using iron powder in a mixture of two ionic liquids, namely 1-methylimidazolium tetrafluoroborate [Hmim]BF4 and 1-benzyl-3-methylimidazolium chloride [Bzmim]Cl. The present method is able to execute single or double Claisen rearrangements of 1,4- or 1,5-bispropargyloxyanthraquinones selectively, so that the desired anthra(mono)furandiones or anthra(bis)furandiones are produced, respectively, as the major product.

Hierridin B Isolated from a Marine Cyanobacterium Alters VDAC1, Mitochondrial Activity, and Cell Cycle Genes on HT-29 Colon Adenocarcinoma Cells

Background: Hierridin B was isolated from a marine cyanobacterium Cyanobium sp. strain and induced cytotoxicity selectively in HT-29 adenocarcinoma cells. The underlying molecular mechanism was not yet elucidated. Methods: HT-29 cells were exposed to the IC₅₀ concentration of hierridin B (100.2 μM) for 48 h. Non-targeted proteomics was performed using 2D gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The mRNA expression of apoptotic and cell cycle genes were analyzed by real-time PCR. Automated quantification of 160 cytoplasm and mitochondrial parameter was done by fluorescence microscopy using CellProfiler software. Results: Proteomics identified 21 significant different proteins, which belonged to protein folding/synthesis and cell structure amongst others. Increase of VDAC1 protein responsible for formation of mitochondrial channels was confirmed by mRNA expression. A 10-fold decrease of cytoskeleton proteins (STMN1, TBCA) provided a link to alterations of the cell cycle. CCNB1 and CCNE mRNA were decreased two-fold, and P21CIP increased 10-fold, indicative of cell cycle arrest. Morphological analysis of mitochondrial parameter confirmed a reduced mitochondrial activity. Conclusion: Hierridin B is a potential anticancer compound that targets mitochondrial activity and function.