Suramin augments the antitumor and antimetastatic activity of pentoxifylline inB16F10 melanoma

Network pharmacology prediction and molecular docking-based strategy to explore the potential mechanism of squalene against inflammation

Squalene (SQ) has been documented in the past for its ability to reduce inflammation, but its mechanism needs more information. In this study, we investigated squalene as an anti-inflammatory drug candidate and the framework involved in treating inflammation (INF) using the network pharmacology concept. The molecular targets of SQ and INF that are available in databases and the overlaps between these targets were demonstrated using InteractiVenn. The protein-protein networks were generated that in turn revealed several key targets and were further processed with Cytoscape. The gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) studies were performed. We also performed molecular docking tests that validated the binding affinity of molecular targets and drugs. A total of 100 SQ targets and 11,417 INF-related targets yielded 93 overlapping targets. Seven core targets, CRHR1, EGFR, ERBB2, HIF1A, SLC6A3, MAP2K1, and F2R were found to be relevant with respective to SQ's anti-inflammatory activity. The underlying mechanism of SQ with regard to INF was interpreted by analyzing various enrichment analyses along with the KEGG pathway. In conclusion, SQ played a vital role in the management of INF by regulating CRHR1, EGFR, ERBB2, HIF1A, SLC6A3, MAP2K1, and F2R. The research outcomes are crucial as they offer significant insights into the use of SQ for combating inflammation.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-024-00217-0.

Discovery of an inhibitor of DNA-driven inflammation that preferentially targets the AIM2 inflammasome

Inflammation driven by DNA sensors is now understood to be important to disease pathogenesis. Here, we describe new inhibitors of DNA sensing, primarily of the inflammasome forming sensor AIM2. Biochemistry and molecular modeling has revealed 4-sulfonic calixarenes as potent inhibitors of AIM2 that likely work by binding competitively to the DNA-binding HIN domain. Although less potent, these AIM2 inhibitors also inhibit DNA sensors cGAS and TLR9 demonstrating a broad utility against DNA-driven inflammatory responses. The 4-sulfonic calixarenes inhibited AIM2-dependent post-stroke T cell death, highlighting a proof of concept that the 4-sulfonic calixarenes could be effective at combating post-stroke immunosuppression. By extension, we propose a broad utility against DNA-driven inflammation in disease. Finally, we reveal that the drug suramin, by virtue of its structural similarities, is an inhibitor of DNA-dependent inflammation and propose that suramin could be rapidly repurposed to meet an increasing clinical need.

The many-sided contributions of NF-κB to T-cell biology in health and disease

T cells (or T lymphocytes) exhibit a myriad of functions in immune responses, ranging from pathogen clearance to autoimmunity, cancer and even non-lymphoid tissue homeostasis. Therefore, deciphering the molecular mechanisms orchestrating their specification, function and gene expression pattern is critical not only for our comprehension of fundamental biology, but also for the discovery of novel therapeutic targets. Among the master regulators of T-cell identity, the functions of the NF-κB family of transcription factors have been under scrutiny for several decades. However, a more precise understanding of their pleiotropic functions is only just emerging. In this review we will provide a global overview of the roles of NF-κB in the different flavors of mature T cells. We aim at highlighting the complex and sometimes diverging roles of the five NF-κB subunits in health and disease.

Zerumbone Suppresses Angiogenesis in HepG2 Cells through Inhibition of Matrix Metalloproteinase-9, Vascular Endothelial Growth Factor, and Vascular Endothelial Growth Factor Receptor Expressions

Context

Due to increase in the number of patients with impaired immunity, the incidence of liver cancer has increased considerably.

Aims

The aim of this study is the investigation the in vitro anticancer effect of zerumbone (ZER) on hepatocellular carcinoma (HCC).

Materials and Methods

The anticancer mechanism of ZER was determined by the rat aortic ring, human umbilical vein endothelial cells (HUVECs) proliferation, chorioallantoic membrane, cell migration, and proliferation inhibition assays.

Results

Our results showed that ZER reduced tube formation by HUVECs effectively inhibits new blood vessel and tissue matrix formation. Western blot analysis revealed that ZER significantly (P < 0.05) decreased expression of molecular effectors of angiogenesis, the matrix metalloproteinase-9, vascular endothelial growth factor (VEGF), and VEGF receptor proteins. We found that ZER inhibited the proliferation and suppressed migration of HepG2 cell in dose-dependent manner.

Statistical Analysis Used

Statistical analyses were performed according to the Statistical Package for Social Science (SPSS) version 17.0. The data were expressed as the mean ± standard deviation and analyzed using a one-way analysis of variance. A P < 0.05 was considered statistically significant.

Conclusion

The study for the first time showed that ZER is an inhibitor angiogenesis, tumor growth, and spread, which is suggested to be the mechanisms for its anti-HCC effect.

SUMMARY

Tumor angiogenesis has currently become an important research area for the control of cancer growth and metastasis. The current study determined the effect of zerumbone on factors associated with angiogenesis that occurs in tumor formation. Abbreviations used: ZER: Zerumbone, MMP-9: Matrix metalloproteinase-9, VEGF: Vascular endothelial growth factor, VEGFR: Vascular endothelial growth factor receptor, HUVECs: Human umbilical vein endothelial cells, HCC: Hepatocellular carcinoma, HIFCS: Heat inactivated fetal calf serum, DMSO: Dimethyl sulfoxide, EDTA: Ethyldiaminetetraacetic acid, Ig: Immunoglobulin, CAM: Chorioallantoic membrane, HRP: Horseradish peroxidase, NIH: National Institutes of Health, MTT: Microtetrazolium, SPSS: Statistical Package for Social Science.

NF-κB c-Rel Is Crucial for the Regulatory T Cell Immune Checkpoint in Cancer

Regulatory T cells (Tregs) play a pivotal role in the inhibition of anti-tumor immune responses. Understanding the mechanisms governing Treg homeostasis may therefore be important for development of effective tumor immunotherapy. We have recently demonstrated a key role for the canonical nuclear factor κB (NF-κB) subunits, p65 and c-Rel, in Treg identity and function. In this report, we show that NF-κB c-Rel ablation specifically impairs the generation and maintenance of the activated Treg (aTreg) subset, which is known to be enriched at sites of tumors. Using mouse models, we demonstrate that melanoma growth is drastically reduced in mice lacking c-Rel, but not p65, in Tregs. Moreover, chemical inhibition of c-Rel function delayed melanoma growth by impairing aTreg-mediated immunosuppression and potentiated the effects of anti-PD-1 immunotherapy. Our studies therefore establish inhibition of NF-κB c-Rel as a viable therapeutic approach for enhancing checkpoint-targeting immunotherapy protocols.

Liquiritigenin Potentiates the Inhibitory Effects of Cisplatin on Invasion and Metastasis Via Downregulation MMP-2/9 and PI3 K/AKT Signaling Pathway in B16F10 Melanoma Cells and Mice Model

Liquiritigenin (LQ) is a flavanone extracted from glycyrrhizae. Previous studies have demonstrated that LQ possesses antimigration properties in HELA and A549 cells. The present research, as an extension of our earlier ones, investigated whether LQ can enhance the antimigration and antiinvasion effect of cis-diamine dichloroplatinum (CDDP) in B16F10 melanoma cell. The data indicated that LQ (25, 50, 100, 200 μM) combined with CDDP (2 μM) significantly reduced B16F10 cell viability compared to CDDP (2 μM)-treated only. The different doses of LQ combined with CDDP significantly suppressed cell migration (21.5%, 49.6%, 75.6%) and cell invasion (26.2%, 51.4%, 69.5%) compared with CDDP-treated alone, suggesting that LQ enhance the inhibition action of CDDP on cell migration and invasion. Moreover, LQ/CDDP combination led to the downregulation of protein expression of MMP-2/9, PI3 K, p-AKT, and upregulated PTEN protein level that play an important role in tumor metastasis progression. Further study demonstrated the enhancement effect of LQ on CDDP suppressing lung metastasis in a mice model being inoculated by the B16F10 melanoma cells. In conclusion, the results suggested that LQ plays an intensive role on CDDP suppressing invasion and metastasis through regulating the PI3 K/AKT signal pathway and suppressing the protein expression of MMP-2/9.

Curbing the focal adhesion kinase and its associated signaling events by pentoxifylline in MDA-MB-231 human breast cancer cells

Pentoxifylline (PTX) is a methylxanthine derivative currently being used in the treatment of peripheral vascular diseases. Recently, we had evaluated its action in human MDA-MB-231 breast cancer cells. PTX exhibited anti-metastatic activity by affecting key processes such as proliferation, adhesion, migration, invasion and apoptosis. In light of the preliminary findings, the present work accounts for the possible mechanistic insights of the pathways affected by PTX. Aberrant Focal Adhesion Kinase (FAK) signaling forms a key determinant in breast cancer and in view of this fact we had investigated downstream processes regulated by FAK. PTX at sub-toxic doses lowers the level of activated FAK, Extracellular Regulated Kinase or Mitogen Activated Protein Kinase (ERK/MAPK), Protein Kinase B (PKB/Akt) affecting cellular proliferation and survival. It blocks G1/S phase of cell cycle by inhibiting the expression of Cyclin D1/Cdk6. Further, it modulates the activities of RhoGTPases and alters actin organization resulting in decreased motility. PTX also delays tumor growth and inhibited blood vessel formation in vivo. In purview of these findings, PTX surely qualifies as a suitable prospect in the intervention of breast cancer.

Preclinical evaluation of the antimetastatic efficacy of Pentoxifylline on A375 human melanoma cell line

Melanoma is the most common malignant skin cancer, appears indestructible and is notoriously resistant to all current modalities of cancer treatment strategies. Pentoxifylline (PTX), a non-specific phosphodiesterase inhibitor, has shown to have radiosensitizing properties for a variety of cancers. Recently, we have shown that PTX exhibits antimetastatic and anti-angiogenic activities in B16F10 melanoma cells in vitro as well as in vivo. In the present study, we have demonstrated the anticancer and antimetastatic potential of PTX against A375 human melanoma cell line at sub-toxic doses. The results implicate that PTX at sub-toxic doses exhibited an inhibitory effect on the ability of cellular proliferation as shown by MTT and colony formation assay. It impedes migration and also induces apoptosis. A375 cells pretreated with PTX showed decrease in adhesion to both Matrigel and Collagen type IV. Further, Gelatin zymography result reveals that PTX treatment decreases the secretion of MMP2 and MMP9. Finally, PTX significantly inhibited A375 subcutaneous tumour xenograft growth without having any toxicity. Thus PTX at sub-toxic doses affected melanoma metastasis at multiple steps in vitro as well as tumour growth in vivo. These data demonstrate its antimetastatic potential and provide preclinical evidence for the development of PTX as a potential agent against metastatic melanoma.

Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

Background

Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC). Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC.

Methods

To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131) using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients.

Results

Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (P = 0.041), increased lymph node metastasis (P = 0.001), less differentiation (P = 0.005), increased recurrence (P = 0.038) and shorter survival (P = 0.004) of the patients.

Conclusion

In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and treatment of OSCC.

EILDV-conjugated, etoposide-loaded biodegradable polymeric micelles directing to tumor metastatic cells overexpressing α4β1 integrin

In the present study, poly(ethylene glycol)-b-poly(ε-caprolactone) micelles loaded with etoposide (ETO) were formulated and further conjugated with pentapeptide Glu-Ile-Leu-Asp-Val (EILDV) to target α4β1 integrin receptor overexpressed on metastatic tumor cell. Using a distinct ratio of carboxyl-terminated poly(ethylene glycol)-block-poly(ε-caprolactone) (HOOC-PEG-b-PCL) to methoxy-poly(ethylene glycol)-block-poly(ε-caprolactone (CH₃O-PEG-b-PCL) polymers, we formulated a series of micellar formulations having different surface densities of EILDV and observed optimum cellular uptake of micelles with 10% EILDV surface density by B16F10 cells. The cytotoxicity of EILDV-conjugated micelles was observed close to 1.5-fold higher than plain ETO after 72 h of drug incubation, demonstrating controlled release of drug inside the cell after enhanced intracellular uptake with the ability to selectively target cancer cells. In addition, EILDV-conjugated micelles inhibited the migration of B16F10 cells effectively compared with plain ETO and non-conjugated micellar formulations when cells were treated with equivalent cytotoxic concentration of the drug, i.e., IC₂₅. B16F10 cells treated with EILDV-conjugated micelles showed a significant reduction in the attachment of cells to the substrate-coated plate compared with non-conjugated micellar formulations, implying retention of the biological activity of EILDV after coupling to micelles. Furthermore, the in vivo experimental metastasis assay conducted on C57BL/6 mice demonstrated significant activity of EIDLV-conjugated micelles in the reduction of pulmonary metastatic nodule formation in both pretreatment and post-treatment methods. In conclusion, EIDLV-conjugated micelles showed higher efficacy in the treatment of metastasis and would be a promising approach in the treatment of metastasis.

Antimelanoma and radioprotective activity of alcoholic aqueous extract of different species of Ocimum in C(57)BL mice

CONTEXT

Various Ocimum species (Labiateae) are commonly used for the treatment of inflammation, stress, diarrhea, and as an antioxidant drug in the Indian ethnic system of medicine.

OBJECTIVE

The present study was carried out to investigate the antimelanoma and radioprotective activity of different species of Ocimum in C(57)BL and Swiss albino mice.

MATERIALS AND METHODS

The antimelanoma activity of 50% alcoholic aqueous leaf extract of five species of Ocimum [Ocimum sanctum (SE), Ocimum gratissimum (GE), Ocimum basilicum (BE), Ocimum canum (CE), and Ocimum kilimandscharicum (KE)] alone or in combination with radiotherapy was determined on the basis of tumor volume, body weight, and survival rate of animals. The radioprotective potential of different species of Ocimum was determined by chromosomal aberration assay. The effect of the alcoholic aqueous extract of different species of Ocimum was also evaluated for the estimation of glutathione level and glutathione S-transferase activity in Swiss albino mice.

RESULTS

The 50% alcoholic aqueous extract of different species of Ocimum administered orally (200 mg/kg, p.o.) resulted in significant reduction in tumor volume, increase in average body weight, and survival rate of mice. The various extracts showed modulatory influence against lethal irradiation doses of gamma radiation in terms of radiation-induced chromosomal damage, while at the same time induced an increase in reduced glutathione level and GST activity.

DISCUSSION AND CONCLUSION

These findings demonstrate that Ocimum species have antimelanoma and radioprotective activity against B(16)F(10) metastatic melanoma cell line-induced metastasis and could be exploited as one of the potential sources for plant-based pharmaceutical products.

Selenium Inhibits Metastasis of Murine Melanoma Cells through the Induction of Cell Cycle Arrest and Cell Death

Background

Melanoma is the most fatal form of skin cancer due to its rapid metastasis. Recently, several studies reported that selenium can induce apoptosis in melanoma cells. However, the precise mechanism remains to be elucidated. In this study, we investigated the effect of selenium on cell proliferation in murine melanoma and on tumor growth and metastasis in C57BL/6 mice.

Methods

Cell proliferation was measured by MTT assay in selenium-treated melanoma cells. Cell cycle distribution was analysized by staining DNA with propidum iodide (PI). mRNA and protein expression related to cell cycle arrest was measured by reverse transcription PCR and western blot. Tumor growth and metastasis was measured by in vivo model.

Results

Selenium was suppressed the proliferation of melanoma cells in a dose dependent manner. The growth inhibition of melanoma by selenium was associated with an arrest of cell cycle distribution at G0/G1 stage. The mRNA and protein level of CDK2/CDK4 was suppressed by treatment with selenium in a time-dependent manner. In vivo, tumor growth was not suppressed by selenium; however tumor metastasis was suppressed by selenium in mouse model.

Conclusion

These results suggest that selenium might be a potent agent to inhibit proliferative activity of melanoma cells.

Epigenetics in human melanoma

BACKGROUND

Recent technological advances have allowed us to examine the human genome in greater detail than ever before. This has opened the door to an improved understanding of the gene expression patterns involved with cancer.

METHODS

A review of the literature was performed to determine the role of epigenetic modifications in human melanoma. We focused the search on histone deacetylation, methylation of gene promoter regions, demethylation of CpG islands, and the role of microRNA. We examined the relationship between human melanoma epigenetics and their importance in tumorigenesis, tumor progression, and inhibition of metastasis. The development and clinical application of select pharmacologic agents are also discussed.

RESULTS

We identified several articles that have extensively studied the role of epigenetics in melanoma, further elucidating the complex processes involved in gene regulation and expression. Several new agents directly affect epigenetic mechanisms in melanoma, with divergent affects on the metastatic potential of melanoma.

CONCLUSIONS

Epigenetic mechanisms have emerged as having a central role in gene regulation of human melanoma, including the identification of several putative tumor suppressor genes and oncogenes. Further research will focus on the development of novel therapeutics that will likely target and alter such epigenetic changes.

Pentoxifylline impedes migration in B16F10 melanoma by modulating Rho GTPase activity and actin organisation

Cancer cell migration is a hallmark of metastatic cascade and compounds that can intervene in this process are clinically important. Pentoxifylline (PTX), a methyl xanthine derivative, inhibits B16F10 melanoma lung homing by inhibiting F10 invasion, MMP secretion and adhesion to matrix components. However, its effect on B16F10 migration remained unexamined, which we investigated in the present study. PTX significantly inhibits F10 migration in scratch wound assay. Elevation in cAMP levels inhibits F10 migration and PTX mediated inhibition of the process was found to be, in part, due to an increase in cellular cAMP levels. PTX induces Protein Kinase A (PKA) activity and PKA inhibitor partly reversed its effects on F10 motility. RhoA and Rac1 GTPases induce B16F10 motility and PTX was found to inhibit migration by affecting these molecules. Stress fibres and lamellipodial protrusions reduced significantly. This was accompanied with inhibition in RhoA and Rac1 membrane localisation. A stark inhibition in RhoA-GTP bound form was also observed. Taken together, the results indicate that PTX, through its phosphodiesterase action, inhibits RhoGTPases and associated actin organisation in B16F10 melanoma, thereby inhibiting cell motility.