Bryostatin-1 inhibits cell proliferation of hepatocarcinoma and induces cell cycle arrest by activation of GSK3β

Marine derived macrolide bryostatin 4 inhibits the TGF-β signaling pathway against acute erythroleukemia

PURPOSE

Acute erythroleukemia (AEL) is a rare and highly aggressive subtype of acute myeloid leukemia (AML) with an extremely poor prognosis when treated with available drugs. Therefore, new investigational agents capable of inducing remission are urgently required.

METHODS

Bioinformatics analysis, western blot and qRT-PCR were used to reveal the potential biological mechanism of bryostatin 4 (B4), an antineoplastic macrolide derived from the marine bryozoan Bugula neritina. Then, in vivo experiments were conducted to evaluate the role of transforming growth factor (TGF)-β signaling in the progression of AEL.

RESULTS

Our results revealed that the proliferation of K562 cells and TF-1 cells was significantly inhibited by B4 at IC50 values of 37 nM and 52 nM, respectively. B4 inhibited TGF-β signaling and its downstream pathway targets, particularly the phosphorylation of Smad2, Smad3, Ras, C-RAF, ERK1/2, and MEK. B4 also played an important role in cell invasion and migration in K562 cells and TF-1 cells by reducing the protein levels of the mesenchymal cell marker vimentin. Moreover, Flow cytometry and western blot analyses demonstrated that B4 induced apoptosis and initiated G0/G1 phase arrest by modulating mitochondrial dysfunction and cyclin-dependent kinase (CDK) expression.

CONCLUSION

These findings indicated that B4 could inhibit the proliferation, migration, invasion, and TGF-β signaling pathways of AEL cells, thus suggesting that B4 possesses therapeutic potential as a treatment for AEL.

miRNAs in radiotherapy resistance of cancer; a comprehensive review

While intensity-modulated radiation therapy-based comprehensive therapy increases outcomes, cancer patients still have a low five-year survival rate and a high recurrence rate. The primary factor contributing to cancer patients' poor prognoses is radiation resistance. A class of endogenous non-coding RNAs, known as microRNAs (miRNAs), controls various biological processes in eukaryotes. These miRNAs influence tumor cell growth, death, migration, invasion, and metastasis, which controls how human carcinoma develops and spreads. The correlation between the unbalanced expression of miRNAs and the prognosis and sensitivity to radiation therapy is well-established. MiRNAs have a significant impact on the regulation of DNA repair, the epithelial-to-mesenchymal transition (EMT), and stemness in the tumor radiation response. But because radio resistance is a complicated phenomena, further research is required to fully comprehend these mechanisms. Radiation response rates vary depending on the modality used, which includes the method of delivery, radiation dosage, tumor stage and grade, confounding medical co-morbidities, and intrinsic tumor microenvironment. Here, we summarize the possible mechanisms through which miRNAs contribute to human tumors' resistance to radiation.

Comprehensive Analysis of a Novel Lipid Metabolism-Related Gene Signature for Predicting the Prognosis and Immune Landscape in Uterine Corpus Endometrial Carcinoma

Lipid metabolism is important in various cancers. However, the association between lipid metabolism and uterine corpus endometrial carcinoma (UCEC) is still unclear. In this study, we collected clinicopathologic parameters and the expression of lipid metabolism-related genes (LMRGs) from the Cancer Genome Atlas (TCGA). A lipid metabolism-related risk model was built and verified. The risk score was developed based on 11 selected LMRGs. The expression of 11 LMRGs was confirmed by qRT-PCR in clinical samples. We found that the model was an independent prediction factor of UCEC in terms of multivariate analysis. The overall survival (OS) of low-risk group was higher than that in the high-risk group. GSEA revealed that MAPK signaling pathway, ERBB signaling pathway, ECM receptor interaction, WNT pathway, and TGF-β signaling pathway were enriched in the high-risk group. Low-risk group was characterized by high tumor mutation burden (TMB) and showed sensitive response to immunotherapy and chemotherapy. In brief, we built a lipid metabolism gene expression-based risk signature which can reflect the prognosis of UCEC patients and their response to chemotherapeutics and immune therapy.

Novel molecules as the emerging trends in cancer treatment: an update

As per World Health Organization cancer remains as a leading killer disease causing nearly 10 million deaths in 2020. Since the burden of cancer increases worldwide, warranting an urgent search for anti-cancer compounds from natural sources. Secondary metabolites from plants, marine organisms exhibit a novel chemical and structural diversity holding a great promise as therapeutics in cancer treatment. These natural metabolites target only the cancer cells and the normal healthy cells are left unharmed. In the emerging trends of cancer treatment, the natural bioactive compounds have long become a part of cancer chemotherapy. In this review, we have tried to compile about eight bioactive compounds from plant origin viz. combretastatin, ginsenoside, lycopene, quercetin, resveratrol, silymarin, sulforaphane and withaferin A, four marine-derived compounds viz. bryostatins, dolastatins, eribulin, plitidepsin and three microorganisms viz. Clostridium, Mycobacterium bovis and Streptococcus pyogenes with their well-established anticancer potential, mechanism of action and clinical establishments are presented.

Marine Natural Products: A Potential Source of Anti-hepatocellular Carcinoma Drugs

Hepatocellular carcinoma (HCC) has high associated morbidity and mortality rates. Although chemical medication represents a primary HCC treatment strategy, low response rates and therapeutic resistance serve to reduce its efficacy. Hence, identifying novel effective drugs is urgently needed, and many researchers have sought to identify new anti-cancer drugs from marine organisms. The marine population is considered a "blue drug bank" of unique anti-cancer compounds with diverse groups of chemical structures. Here, we discuss marine-derived compounds, including PM060184 and bryostatin-1, with demonstrated anti-cancer activity in vitro or in vivo. Based on the marine source (sponges, algae, coral, bacteria, and fungi), we introduce pharmacological parameters, compound-induced cytotoxicity, effects on apoptosis and metastasis, and potential molecular mechanisms. Cumulatively, this review provides insights into anti-HCC research conducted to date in the field of marine natural products and marine-derived compounds, as well as the potential pharmacological mechanisms of these compounds and their status in drug development.

Application of marine natural products in drug research

New diseases are emerging as the environment changes, so drug manufacturers are always on the lookout for new resources to develop effective and safe drugs. In recent years, many bioactive substances have been produced in the marine environment, which represents an alternative resource for new drugs used to combat major diseases such as cancer or inflammation. Many marine-derived medicinal substances are in preclinical or early stage of clinical development, and some marine drugs have been put on the market, such as ET743 (Yondelis®). This review presents the sources, activities, mechanisms of action and syntheses of bioactive substances based on marine natural products in clinical trials and on the market, which is helpful to understand the progress of drug research by application of marine natural products.

Preclinical and Clinical Studies on Bryostatins, A Class of Marine-Derived Protein Kinase C Modulators: A Mini-Review

Bryostatins are complex macrolactones isolated from marine organisms Bryozoan Bugula neritina. They are potent modulators of protein kinase C isozymes (PKCα: ki = 1.3-188 nM), and are one of the most extensively investigated marine natural products in clinical trials. Although ~21 natural bryostatins have been isolated, however only bryostatin-1 (1) has received much interest among medicinal chemists and clinicians. The structure-activity relationship of bryostatins has been well established, with the identification of key pharmacophoric features important for PKC modulation. The low natural abundance and the long synthetic route have prompted medicinal chemists to come-up with simplified analogs. Bryostatin skeleton comprises three pyran rings connected to each other to form a macrocyclic lactone. The simplest analog 27 contains only one pyran, which is also able to modulate the PKCα activity; however, the cyclic framework appears to be essential for the desired level of potency. Another simplified analog 17 ("picolog") exhibited potent and in-vivo efficacy against lymphoma. Bryostatin-1 (1) has shown an acceptable intravenous pharmacokinetic profile in mice and displayed promising in-vivo efficacy in mice models of various cancers and Alzheimer's disease. Bryostatin-1 was investigated in numerous Phase I/II oncology clinical trials; it has shown minimal effect as a single agent, however, provided encouraging results in combination with other chemotherapy agents. FDA has granted orphan drug status to bryostatin-1 in combination with paclitaxel for esophageal cancer. Bryostatin-1 has also received orphan drug status for fragile X syndrome. Bryostatin-1 was also investigated in clinical studies for Alzheimer's disease and HIV infection. In a nutshell, the natural as well as synthetic bryostatins have generated a strong hope to emerge as treatment for cancer along with many other diseases.

Recent advances in nanoscale materials for antibody-based cancer theranostics

The quest for advanced management tools or options of various cancers has been on the rise to efficiently reduce their risks of mortality without the demerits of conventional treatments (e.g., undesirable side effects of the medications on non-target tissues, non-targeted distribution, slow clearance of the administered drugs, and the development of drug resistance over the duration of therapy). In this context, nanomaterials-antibody conjugates can offer numerous advantages in the development of cancer theranostics over conventional delivery systems (e.g., highly specific and enhanced biodistribution of the drug in targeted tissues, prolonged systemic circulation, low toxicity, and minimally invasive molecular imaging). This review comprehensively discusses and evaluates recent advances in the application of nanomaterial-antibody bioconjugates for cancer theranostics for the further advancement in the control of diverse cancerous diseases. Further, discussion is expanded to cover the various challenges and limitations associated with the design and development of nanomaterial-antibody conjugates applicable towards better management of cancer.

PIGU promotes hepatocellular carcinoma progression through activating NF-κB pathway and increasing immune escape

Hepatocellular carcinoma (HCC) is the sixth most common malignancy and has the third highest mortality rate among all tumors. Previous studies found that phosphatidylinositol glycan anchor biosynthesis class U (PIGU) was highly expressed in hepatocellular carcinoma (HCC), while the function of PIGU in HCC remains unknown. Here, we deeply investigated this issue. The expression levels of PIGU in HCC cells were measured by Western blotting. The functions of PIGU in HCC cells were assessed in vitro, followed by assessing the nuclear factor-kappa B (NF-κB) pathway-related protein levels. The xenograft mouse models were conducted to investigate the effects of PIGU in vivo. Moreover, the effects of PIGU downregulation on natural killer (NK)-92 cell-mediated cell killing were detected. The results showed that PIGU was highly expressed in HCC cells compared with normal liver cells. Functional studies showed that PIGU promoted viability, cell cycle progression, migration, and invasion and suppressed apoptosis in HCC cells. Mechanism studies indicated that PIGU silencing blocked the NF-κB pathway and the blockade of the NF-κB pathway reversed the effects of PIGU overexpression on HCC cell function, including cell viability, migration, invasion, and apoptosis. In vivo studies further verified the effects of PIGU on HCC cell function, and demonstrated that PIGU knockdown suppressed tumorigenesis. Additionally, we proved that PIGU downregulation significantly enhanced the sensitivity of HCC cells to NK-92 cell cytolysis. Collectively, PIGU may promote HCC progression through activating the NF-κB pathway and promoting immune escape, indicating that PIGU may serve as a promising therapeutic target for HCC treatment.

Long non-coding RNA KCNQ1OT1 up-regulates CTNND1 by sponging miR-329-3p to induce the proliferation, migration, invasion, and inhibit apoptosis of colorectal cancer cells

Background

Long non-coding RNAs (lncRNAs) have been certified to be involved in the occurrence and growth of diverse cancers, including CRC. The purpose of the research was to explore the effects of lncRNA KCNQ1 overlapping transcript 1 (KCNQ1OT1) on proliferation, migration, invasion, and apoptosis in CRC cells and its mechanism.

Methods

The levels of KCNQ1OT1 and miR-329-3p were examined by quantitative real-time polymerase chain reaction (qRT-PCR) in CRC tissues and cells. The mRNA and protein levels of catenin delta-1 (CTNND1) were measured by qRT-PCR and western blot analysis, respectively. The targets of KCNQ1OT1 and miR-329-3p were predicted by online software and confirmed by luciferase reporter assay. The cell proliferation, migration, invasion, and apoptosis were examined using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), transwell, and apoptosis assay. The expression levels of CyclinD1, Bcl-2, MMP9, Cleaved-casp-3, and E-cadherin in SW480 and LS1034 cells were gauged by western blot analysis. Xenograft tumor model was structured to prove the biological role of KCNQ1OT1 of CRC in vivo.

Results

The levels of KCNQ1OT1 and CTNND1 were significantly increased in CRC tissues and cells. Knockdown of KCNQ1OT1 suppressed proliferation, migration, invasion, and induced apoptosis in CRC cells. Conversely, CTNND1 overexpression reversed the impact of KCNQ1OT1 knockdown on CRC cells. Moreover, CTNND1 was verified as a direct target of miR-329-3p, and miR-329-3p could specially bind to KCNQ1OT1. Also, the down-regulation of KCNQ1OT1 triggered the CRC progress by up-regulating CTNND1 expression in CRC cells. Besides, KCNQ1OT1 knockdown inhibited CRC tumor growth through the miR-329-3p/CTNND1 axis in vivo.

Conclusion

Our results indicated that KCNQ1OT1 could positively regulate CTNND1 expression by sponging miR-329-3p, thereby boosting the progression of CRC. Our findings provided the underlying therapy targets for CRC.

Marine Natural Products with High Anticancer Activities

This review covers recent literature from 2012-2019 concerning 170 marine natural products and their semisynthetic analogues with strong anticancer biological activities. Reports that shed light on cellular and molecular mechanisms and biological functions of these compounds, thus advancing the understanding in cancer biology are also included. Biosynthetic studies and total syntheses, which have provided access to derivatives and have contributed to the proper structure or stereochemistry elucidation or revision are mentioned. The natural compounds isolated from marine organisms are divided into nine groups, namely: alkaloids, sterols and steroids, glycosides, terpenes and terpenoids, macrolides, polypeptides, quinones, phenols and polyphenols, and miscellaneous products. An emphasis is placed on several drugs originating from marine natural products that have already been marketed or are currently in clinical trials.