Antimetastatic Properties Research Articles

Kisspeptin and GPR54 Receptor Expression in Endometrial Cancer Tissue

Kisspeptin (KISS) is a natural peptide-discovered in 1996 as a factor inhibiting the ability to metastasize in malignant melanoma. This protein plays also a regulatory role in the process of puberty, the menstrual cycle, spermatogenesis, implantation and development of the human placenta. The present study aimed to evaluate the expression of KISS and its receptor GPR54 in endometrial cancer (EC) tissue, depending on the histological type of cancer, its stage, various demographic characteristics, and clinical conditions in 214 hysterectomy patients. Expression of KISS and GPR54 was confirmed in 99.5% and 100% of the cases, respectively. Hormone replacement therapy and the coexistence of the anti-Müllerian type 2 receptor in cancer tissue enhanced KISS expression. Smoking, on the other hand, decreased KISS expression. GPR54 expression increased with the advancement of the disease (according to FIGO classification). Also, the presence of the anti-Müllerian type 2 receptor in EC increased the level of GPR54. Hypertension, age and miscarriage harmed the presence of GPR54. The histological type of cancer, diabetes type 2, body mass index, hormonal contraception, number of deliveries, birth weight of newborns, breastfeeding time, and the presence of AMH in EC tissue were not associated with the expression of either KISS nor GPR54. The KISS level was also significantly related to the GPR54 level. Considering that KISS is a non-toxic peptide with antimetastatic properties, further investigation is essential to determine the clinical significance of this peptide.

The anti-metastasis effect of low-dose carbon monoxide

: Metastasis is the primary cause of cancer-related deaths. Because of the anatomically diffused localizations in different organs, treating metastatic cancer with conventional surgery or radiotherapy is challenging. Systemic therapies, including chemotherapy, immunotherapy, and targeted therapy, are used for metastatic cancer treatment. However, resistance to chemotherapy often develops over time, and immunotherapy or targeted therapy is not available for every cancer type. Improved systemic therapies for metastatic cancer are urgently needed. Among all forms of cancer, pancreatic ductal adenocarcinoma (PDAC) is a lethal type due to the following characteristics: early distant metastasis, abundant desmoplastic stroma, insufficient therapeutics, and frequent chemoresistance. Carbon monoxide (CO) is produced endogenously in humans and has been established as an important, biologically active signaling molecule. Accumulating evidence suggests the therapeutic applications of safe, low-dose CO for various diseases. Recently, low-dose CO was shown to suppress metastasis of PDAC in an orthotopic mouse model of liver metastasis and a spontaneous PDAC metastasis mouse model after the removal of primary tumor xenograft tumors. In this mini-review, we discuss the findings and the potential development of CO-based systemic therapies for metastatic cancer. Specifically, many non-inhalation CO delivery modalities with easy control of dosages have been developed and can be further studied for their anti-metastatic properties.

Overview of the Role of Vanillin in Neurodegenerative Diseases and Neuropathophysiological Conditions.

Nowadays, bioactive natural products play key roles in drug development due to their safety profile and strong antioxidant power. Vanillin is a natural phenolic compound found in several vanilla beans and widely used for food, cosmetic, and pharmaceutical products. Besides its industrial applications, vanillin possesses several beneficial effects for human health, such as antioxidant activity in addition to anti-inflammatory, anti-mutagenic, anti-metastatic, and anti-depressant properties. Moreover, vanillin exhibits neuroprotective effects on multiple neurological disorders and neuropathophysiological conditions. This study reviews the mechanisms of action by which vanillin prevents neuroinflammation and neurodegeneration in vitro and in vivo systems, in order to provide the latest views on the beneficial properties of this molecule in chronic neurodegenerative diseases and neuropathophysiological conditions.

A series of ligustrazine platinum(IV) complexes with potent anti-proliferative and anti-metastatic properties that exert chemotherapeutic and immunotherapeutic effects.

The development of novel anticancer drugs with antiproliferative and antimetastatic activities is of great importance in the pharmaceutical field. Herein, a series of ligustrazine (LSZ) platinum(IV) complexes with chemotherapeutic and immunotherapeutic effects were designed, prepared and evaluated as antitumor agents for the first time. Complex 4 with potent antitumor activities both in vitro and in vivo was screened out as a candidate. Notably, it displays significantly more effective anti-metastatic activities than the platinum(II) drugs cisplatin and oxaliplatin. Mechanism detection discloses that it causes serious DNA damage and increases the expression of γ-H2AX and P53. Then, the apoptosis of tumor cells is promoted by activating the mitochondrial apoptotic pathway Bcl-2/Bax/caspase-3 and causing autophagy via modulating LC3-I/II and P62 expression. Furthermore, the immune therapeutic responses are significantly elevated by blocking HIF-1α, ERK 1/2 and COX-2 pathways to reduce PD-L1 expression, and further increasing CD3+ and CD8+ T cells to elevate T cell immunity in tumors. Tumor metastasis is blocked by the synergistic functions of DNA damage, hypoxia modulation and immune activation.

Antimetastatic Properties of Prodigiosin and the BH3-Mimetic Obatoclax (GX15-070) in Melanoma

Metastasis is the primary cause of death in cancer patients. Many current chemotherapeutic agents only show cytotoxic, but not antimetastatic properties. This leads to a reduction in tumor size, but allows cancer cells to disseminate, which ultimately causes patient death. Therefore, novel anticancer compounds with both effects need to be developed. In this work, we analyze the antimetastatic properties of prodigiosin and obatoclax (GX15-070), anticancer drugs of the Prodiginines (PGs) family. We studied PGs' effects on cellular adhesion and morphology in the human primary and metastatic melanoma cell lines, SK-MEL-28 and SK-MEL-5, and in the murine melanoma cell line, B16F10A. Cell adhesion sharply decreased in the treated cells, and this was accompanied by a reduction in filopodia protrusions and a significant decrease in the number of focal-adhesion structures. Moreover, cell migration was assessed through the wound-healing assay and cell motility was severely inhibited after 24 h of treatment. To elucidate the molecular mechanisms involved, changes in metastasis-related genes were analyzed through a gene-expression array. Key genes related to cellular invasion, migration and chemoresistance were significantly down-regulated. Finally, an in vivo model of melanoma-induced lung metastasis was established and significant differences in lung tumors were observed in the obatoclax-treated mice. Altogether, these results describe, in depth, PGs' cellular antimetastatic effects and identify in vivo antimetastatic properties of Obatoclax.

The Complete Chloroplast Genome Sequence of Eupatorium fortunei: Genome Organization and Comparison with Related Species.

Eupatorium fortunei Turcz, a perennial herb of the Asteraceae family, is one of the horticultural and medicinal plants used for curing various diseases and is widely distributed in China and other Asian countries. It possesses antibacterial, antimetastatic, antiangiogenic, and antioxidant properties along with anticancer potential. However, the intrageneric classification and phylogenetic relationships within Eupatorium have long been controversial due to the lack of high-resolution molecular markers, and the complete chloroplast (cp) genome sequencing has not been reported with new evolutionary insights. In the present study, E. fortunei was used as an experimental material, and its genome was sequenced using high-throughput sequencing technology. We assembled the complete cp genome, and a systematic analysis was conducted for E. fortunei, acquiring the correspondence of its NCBI accession number (OK545755). The results showed that the cp genome of E. fortunei is a typical tetrad structure with a total length of 152,401 bp, and the genome encodes 133 genes. Analysis of the complete cp genomes of 20 Eupatorieae shows that the number of simple sequence repeats (SSRs) ranged from 19 to 36 while the number of long sequence repeats was 50 in all cases. Eleven highly divergent regions were identified and are potentially useful for the DNA barcoding of Eupatorieae. Phylogenetic analysis among 22 species based on protein-coding genes strongly supported that E. fortunei is more closely related to Praxelis clematidea and belongs to the same branch. The genome assembly and analysis of the cp genome of E. fortunei will facilitate the identification, taxonomy, and utilization of E. fortunei as well as provide more accurate evidence for the taxonomic identification and localization of Asteraceae plants.

Real-Time Monitoring of the Cytotoxic and Antimetastatic Properties of Cannabidiol in Human Oral Squamous Cell Carcinoma Cells Using Electric Cell-Substrate Impedance Sensing.

Cannabidiol (CBD) is an active natural compound that is extracted from Cannabis sativa. Previous studies show that CBD is a nonpsychotropic compound with significant anticancer effects. This study determines its cytotoxic effect on oral cancer cells and OEC-M1 cells and compares the outcomes with a chemotherapeutic drug, cisplatin. This study has investigated the effect of CBD on the viability, apoptosis, morphology, and migration of OEC-M1 cells. Electric cell-substrate impedance sensing (ECIS) is used to measure the change in cell impedance for cells that are treated with a series concentration of CBD for 24 h. AlamarBlue and annexin V/7-AAD staining assays show that CBD has a cytotoxic effect on cell viability and induces cell apoptosis. ECIS analysis shows that CBD decreases the overall resistance and morphological parameters at 4 kHz in a concentration-dependent manner. There is a significant reduction in the wound-healing recovery rate for cells that are treated with 30 μM CBD. This study demonstrates that ECIS can be used for in vitro screening of new chemotherapy and is more sensitive, functional, and comprehensive than traditional biochemical assays. CBD also increases cytotoxicity on cell survival and the migration of oral cancer cells, so it may be a therapeutic drug for oral cancer.

Abstract IA017: Iloprost for lung cancer prevention

Abstract Iloprost is a prostacyclin analogue with anti-metastatic, vasodilatory and anti-inflammatory properties. Increased prostacyclin is protective in pre-clinical murine models of adenocarcinoma and squamous cell carcinoma (SCC), including tobacco smoke. The chemoprotective properties are independent of the single cell surface prostacyclin receptor, as knockout animals are still protected. Clinical studies of iloprost have included both oral and inhaled preparations. Oral iloprost improves endobronchial dysplasia (pre-cursor lesions for invasive SCC) in former smokers. Dysplastic lesions are now being characterized beyond histology to better understand lesion evolution. Investigations into the mechanism of iloprost associated cancer prevention (including effects on basal progenitor cells, progenitor multi-potentiality, and differentiation) and biomarkers predicting response will be presented, along with an outline for an upcoming clinical trial in former smokers. Citation Format: Robert Keith. Iloprost for lung cancer prevention [abstract]. In: Proceedings of the Second Biennial NCI Meeting: Translational Advances in Cancer Prevention Agent Development (TACPAD); 2022 Sep 7-9. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_2): Abstract nr IA017.

GC, GC/MS Analysis, and Biological Effects of Essential Oils from Thymus mastchina and Elettaria cardamomum

Spanish marjoram (Thymus mastichina) and cardamom (Elettaria cardamomum) are traditional aromatic plants with which several pharmacological properties have been associated. In this study, the volatile composition, antioxidative and antimigratory effects on human breast cancer (MDA-MB-468 cell line), antimicrobial activity, and antibiofilm effect were evaluated. Results obtained via treatment of human breast cancer cells generally indicated an inhibitory effect of both essential oils (EOs) on cell viability (after long-term treatment) and antioxidative potential, as well as the reduction of nitric oxide levels. Antimigratory effects were revealed, suggesting that these EOs could possess significant antimetastatic properties and stop tumor progression and growth. The antimicrobial activities of both EOs were determined using the disc diffusion method and minimal inhibition concentration, while antibiofilm activity was evaluated by means of mass spectrometry. The best antimicrobial effects of T. mastichina EO were found against the yeast Candida glabrata and the G+ bacterium Listeria monocytogenes using the disc diffusion and minimal inhibitory concentration methods. E. cardamomum EO was found to be most effective against Pseudomas fluorescens biofilm using both methods. Similarly, better effects of this oil were observed on G- compared to G+ bacterial strains. Our study confirms that T. mastichina and E. cardamomum EOs act to change the protein structure of older P. fluorescens biofilms. The results underline the potential use of these EOs in manufactured products, such as foodstuffs, cosmetics, and pharmaceuticals.

Chemopreventive role of probiotics against cancer: a comprehensive mechanistic review.

Probiotics use different mechanisms such as intestinal barrier improvement, bacterial translocation and maintaining gut microbiota homeostasis to treat cancer. Probiotics' ability to induce apoptosis against tumor cells makes them more effective to treat cancer. Moreover, probiotics stimulate immune function through an immunomodulation mechanism that induces an anti-tumor effect. There are different strains of probiotics, but the most important ones are lactic acid bacteria (LAB) having antagonistic and anti-mutagenic activities. Live and dead probiotics have anti-inflammatory, anti-proliferative, anti-oxidant and anti-metastatic properties which are useful to fight against different diseases, especially cancer. The main focus of this article is to review the anti-cancerous properties of probiotics and their role in the reduction of different types of cancer. However, further investigations are in progress to improve the efficiency of probiotics in cancer treatment.

Rare Association Between Osteogenesis Imperfecta and Chondrosarcoma: Could a Pathogenic Variant in the Gene SERPINF1 Explain It?

Osteogenesis imperfecta (OI) type VI is a rare inherited disorder of the connective tissue caused by pathogenic variants inSERPINF1 gene, which encodes the pigment epithelium-derived factor (PEDF). PEDF is implicated in many biologic processes, including an anti-cancer role. This information is supported by in vitro and in vivo studies that evidenced its anti-angiogenic, anti-tumorigenic, and anti-metastatic properties. Although OI is related to skeletal changes such as bone fragility and deformities, as well as to other connective tissue defects, it does not represent a greater predisposition to the development of skeletal tumors. Here, we report on an adult with OI in which a deletion in exon 8 of the SERPINF1 gene (c.1152_1170del; p.384_390del) was identified. The patient presented popcorn calcification in both femoral epiphyses, but one of them presented radiological characteristics and evolution suspected of malignancy. Later, it was diagnosed as chondrosarcoma. This paper discusses that OI type VI patients may be at risk of developing some types of cancer.

Rapid green-assisted synthesis and functionalization of superparamagnetic magnetite nanoparticles using Sumac extract and assessment of their cellular toxicity, uptake, and anti-metastasis property

Modifying the surface properties of superparamagnetic magnetite nanoparticles (SPMNPs) is essential for their stabilization and functionalization in biomedical applications. This study explored the use of Sumac (Rhus coriaria) plant extract as a green stabilizer for SPMNPs. Herein, we fabricated the aqueous colloidal suspension of SPMNPs via a facile and rapid green-assisted co-precipitation method using the extract solution as a green stabilizer (SS), the results were then compared to the uncoated SPMNPs (SB). Physicochemical properties of the as-synthesized NPs were characterized. The XRD planes of both samples matched the typical Fe3O4 NPs with a high degree of crystallinity. FESEM and TEM revealed that SS were spherical and mono-dispersed with an average particle size of 11 nm, while the average particle size of SB was measured to be around 9.9 nm. The elemental compositions of the SS were approved by the EDX technique. FTIR and TGA results confirmed the presence of functional groups in the extract components and their interactions with SPMNPs. Based on the DLS analysis, Sumac extracts significantly prolonged the stability and increased the zeta potential value of the SPMNPs nanofluid from −28.2 to −44.8 mV. The magnetization (Ms) values of SB and SS samples were found to be 62.95 emu/g and 139.56 emu/g, respectively. VSM results pointed out that Sumac extracts dramatically enhanced the saturation magnetization of the coated SPMNPs. In vitro cytotoxicity and scratch assays of the SS against MCF-7 cells indicated the non-toxicity, proliferation modulation, and growth inhibition abilities (anti-metastatic properties) of the modified NPs. In addition, the cellular uptake assessment of SS on the MCF-7 cancer cell line revealed a dose-dependent internalization. Our findings implied that this hydrophilic, highly magnetic, stable, and biocompatible SS is probably capable of being used in a wide range of biomedical applications such as MRI, magnetic hyperthermia, and cancer treatment.

Novel secretion modification region (SMR) peptide exhibits anti-metastatic properties in human breast cancer cells

Breast cancer is the second leading cause of cancer-related mortality in women worldwide, with nearly 90% attributed to metastatic progression. Exosomes containing epithelial–mesenchymal transition (EMT) ‘programs’ transmit pro-metastatic phenotypes. Our group discovered and developed a novel anti-cancer SMR peptide that antagonizes breast cancer cell exosome release resulting in cell cycle arrest and tumor growth suppression. This study aims to evaluate the anti-metastatic capabilities of the SMR peptide, focusing on exosomes and EMT. Breast cancer cell lines MDA-MB-231 and MCF-7 were treated with the SMRwt peptide, and the following assays were performed: cell wound-healing, migration, invasion. The SMRwt peptide consists of the following amino acid sequence VGFPVAAVGFPVDYKDDDDK and contains the SMR domain (66VGFPV70) of the HIV-1 Nef protein. Western blot analysis detected epithelial and mesenchymal markers to evaluate EMT progression. Extracellular vesicle type and quantity were assessed through NanoSight analysis. Mortalin and Vimentin knockdown was achieved through antibody targeting and miRNAs. Data gathered demonstrated that the SMR peptide interacts with Mortalin and Vimentin to inhibit pro-EMT exosome release and induce EMT tumor suppressor protein expression. Specifically, SMRwt treatment reduced mesenchymal markers Mortalin and Vimentin expression, while the epithelial marker E-cadherin expression was increased in breast cancer cells and breast cancer-derived exosomes. The SMR peptide specificity was identified as no effect was observed for MCF-10A exosome release or function. Direct Mortalin knockdown paralleled the results of SMR peptide treatment with an effective blockade of breast cancer cell migration. Conversely, the invasion assay differed between breast cancer cell lines with invasion blocked for in MCF-7 but not in MDA-MB-231. These results reinforce the therapeutic value of targeting breast cancer exosome release and reinforce Mortalin and Vimentin as critical regulators and therapeutic targets in breast cancer cell progression, EMT, and metastatic potential. A greater understanding of the SMR peptide mechanism of action will benefit the therapeutic design of anti-metastatic agents.

Sanguinarine Inhibition of TNF-α-Induced CCL2, IKBKE/NF-κB/ERK1/2 Signaling Pathway, and Cell Migration in Human Triple-Negative Breast Cancer Cells.

Angiogenesis is a process that drives breast cancer (BC) progression and metastasis, which is linked to the altered inflammatory process, particularly in triple-negative breast cancer (TNBC). In targeting inflammatory angiogenesis, natural compounds are a promising option for managing BC. Thus, this study was designed to determine the natural alkaloid sanguinarine (SANG) potential for its antiangiogenic and antimetastatic properties in triple-negative breast cancer (TNBC) cells. The cytotoxic effect of SANG was examined in MDA-MB-231 and MDA-MB-468 cell models at a low molecular level. In this study, SANG remarkably inhibited the inflammatory mediator chemokine CCL2 in MDA-MB-231 and MDA-MB-468 cells. Furthermore, qRT-PCR confirmed with Western analysis studies showed that mRNA CCL2 repression was concurrent with reducing its main regulator IKBKE and NF-κB signaling pathway proteins in both TNBC cell lines. The total ERK1/2 protein was inhibited in the more responsive MDA-MB-231 cells. SANG exhibited a higher potential to inhibit cell migration in MDA-MB-231 cells compared to MDA-MB-468 cells. Data obtained in this study suggest a unique antiangiogenic and antimetastatic effect of SANG in the MDA-MB-231 cell model. These effects are related to the compound’s ability to inhibit the angiogenic CCL2 and impact the ERK1/2 pathway. Therefore, SANG use may be recommended as a component of the therapeutic strategy for TNBC.

Abstract 1552: Deciphering the mechanism of action of Long non-coding RNA fer1l4 in the suppression of invasion, migration and metastasis of colon cell carcinoma

Abstract Introduction: p73 transcription factor belongs to the p53 tumor suppressor family. Recent studies revealed that p73 wields its tumor suppressor properties by inhibiting metastasis. Although the literature on the p73 transcriptional circuit has chiefly concentrated on protein-coding genes, it has been progressively pointed out that p73 is also able to transcriptionally modulate non-coding RNA (ncRNA) members. These involve microRNAs (miRNAs) and many p53-regulated long non-coding RNAs (lncRNAs). Methods: Identification of p73 binding sites in the FER1L4 promoter region was made by JASPER and TF BIND which was further confirmed by chromatin immunoprecipitation (ChIP) and site-directed mutagenesis experiments. Effect of FER1L4 in p73 mediated cell cycle arrest and apoptosis was checked by cell cycle analysis, Annexin-V/PI, and TUNEL apoptosis assays. Depletion of FER1L4 enhanced cell proliferation, migration, and invasion in a p73-dependent manner. Furthermore, RNA-In situ hybridization (RNA-ISH) analysis of non-metastatic and metastatic human colon cancer tissue samples was carried out to compare the levels of FER1L4 and p73 in metastatic and non-metastatic tumor tissue samples. We also checked the expression of different miRNA including miR1273g-3p and its effect on PTEN expression. Results: We have identified lncRNA FER1L4 as a novel p73 transcriptional target that gets induced as a result of genotoxic stress. The binding of p73 to FER1L4 promoter was established by bioinformatics analysis, luciferase reporter, and ChIP assays. Both FER1L4 and p73 knockdown enhanced the migration and invasion rate of colorectal cancer cells. FER1L4 knockdown reduced E-cadherin expression and enhanced the expression of N-cadherin, Vimentin, Snail, and Fibronectin. Cell cycle assays revealed that FER1L4 induces a G2/M cell cycle arrest in a p73-dependent manner. Annexin V/PI and TUNEL assays revealed FER1L4 induced apoptosis in HCT116p53-/-p73+/+ colon cancer cells under genotoxic stress and FER1L4 knockdown inhibited apoptosis even in the presence of p73. The expression of pro-apoptotic markers such as Bad, Bax, Bik, Bim, Bid, Bak and PUMA decreased upon FER1L4 and p73 knockdown. FER1L4 sponges the expression of miR-1273g-3p, which in turn increases PTEN expression leading to cell cycle arrest. RNA In-situ hybridization revealed the down-regulation of both p73 and FER1L4 expression in metastatic colon cancer tissue as compared to non-metastatic tissue. Conclusion: We provide conclusive proof that p73 exerts its anti-metastatic properties by inducing lncRNA FER1L4 in response to genotoxic stress which in turn sponges the expression of miR1273g-3p, a regulator of PTEN. Citation Format: Daman Saluja, Apoorva Uboveja, Yatendra kumar Satija, Fouzia Siraj. Deciphering the mechanism of action of Long non-coding RNA fer1l4 in the suppression of invasion, migration and metastasis of colon cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1552.

Abstract 347: Comparative activity of MBQ-167 metabolites in metastatic breast cancer

Abstract Metastasis continues to be the most difficult phase for cancer treatment due to few targeted therapy options. Therefore, we focus on targeting the Rho GTPases Rac1 and Cdc42, key drivers of the primary steps of metastasis: cell migration and invasion. We developed MBQ-167 as a small molecule dual inhibitor for Rac1 and Cdc42 activation with IC50s of 103 and 78 nM, respectively. In metastatic human breast cancer cells, MBQ-167 inhibits the Rac/Cdc42 downstream effector p21-activated kinase (PAK)/LIM kinase/Cofilin signaling, lamellipodia extension, and thus, cell polarity, and migration. In addition, in metastatic breast cancer cells, MBQ-167 inhibits cell proliferation and cell cycle progression to ultimately induce apoptosis via anoikis. MBQ-167 inhibits tumor growth and metastasis in experimental and spontaneous HER-positive and Triple negative breast cancer (TNBC) mouse models. MBQ-167 has 35% bioavailability and is not toxic in rodent or canine models up to 1000 mg/kg. Therefore, we are further developing MBQ-167 as a lead anti metastatic cancer compound. The objective in this study is to elucidate potential activity of MBQ-167 metabolites. Prior work has identified MBQ-167 metabolites via LC MS/MS from a mammalian liver microsome (rats and human) assay. Four of the MBQ-167 metabolites with the highest MS peak area, were analyzed in metastatic breast cancer cell lines, for cell viability via MTT assays and apoptosis via caspase 3/7 assays. We report that the metabolites M6, M7, M8, and M9 did not inhibit cell viability or induce apoptosis at 250 or 500 nM in HER2-type MDA-MB-435, and TNBC MDA-MB-231 and MDA-MB-468 breast cancer cell lines, compared to MBQ-167. We next analyzed whether these metabolites could inhibit the activation of Rac and Cdc42 by analyzing the phosphorylation status of its downstream effector p-21 activated kinase isoforms 1/2/3 (PAK1/2/3). When MBQ-167 and metabolites at 250nM were incubated for 24h in HER2-type MDA-MB-435 metastatic cancer cells, and the lysates western blotted with antibodies to total PAK1/2/3 or phospho-Pak1/2/3, we found a decrease in the phosphorylation levels of PAK in response to MBQ-167 and metabolite M6. However, since the peak area of M6 in the microsome assay is only 6% compared to MBQ-167, we conclude that MBQ-167 is the major active compound with anti-metastatic cancer properties. Citation Format: Julia I. Medina, Eliud Hernández, Cornelis Vlaar, Suranganie Dharmawardhane. Comparative activity of MBQ-167 metabolites in metastatic breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 347.

Melatonin and andrographolide synergize to inhibit the colospheroid phenotype by targeting Wnt/beta-catenin signaling.

β-catenin signaling, and angiogenesis are associated with colospheroid (CSC), development. CSCs, spheroids derived from colon cancer cells, are responsible for metastasis, drug resistance, and disease recurrence. Whether dysregulating β-catenin and inhibiting angiogenesis reduce CSC growth is unknown. In this study, the molecular mechanism of CSC growth inhibition was evaluated using a novel combination of melatonin (MLT) and andrographolide (AGP). These drugs have anticarcinogenic, antioxidant, and antimetastatic properties. CSCs were obtained from two metastatic colon cancer cell lines (HT29 and HCT-15). The viability and stemness were monitored (FDA propidium iodide staining and immunoblot for CD44, CD133, Nanog, Sox2, and Oct4). The drug combination synergistically diminished stemness via increased reactive oxygen species (ROS) levels, reduced mitochondrial membrane potential and ATP level. MLT + AGP induced cell death by inhibiting β-catenin expression and its downregulatory signals, Cyclin D1, c-Myc. MLT + AGP treated cells exhibited translocation of phospho-β-catenin to the nucleus and dephosphorylated-β-catenin. Downregulation of β-catenin activation and its transcription factors (TCF4 and LEF1) and GTP binding/G-protein related activity were found in the dual therapy. Angiogenic inhibition is consistent with downregulation of VEGF messenger RNA transcripts (VEGF189), phosphorylated VEGF receptor protein expression, matrigel invasion, and capillary tube inhibition. In vivo, the intravenous injection of MLT + AGP slowed HT29 metastatic colon cancer. Histopathology indicated significant reduction in microvascular density and tumor index. Immunohistochemistry for caspase 7, and β-catenin found increased apoptosis and downregulation of β-catenin signals. The mechanism(s) of decreased colospheroids growth were the inhibition of the Wnt/β-catenin pathway. Our results provide a rationale for using MLT in combination with AGP for the inhibition of CRCs.

Evaluation of Wound Healing and Antibacterial Potential of Greyia radlkoferi Szyszyl. Ethanolic Leaf Extract.

Angiogenesis is an essential mechanism in both physiological and pathological functions, such as wound healing and cancer metastasis. Several growth factors mediate angiogenesis, including vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF). This study evaluated the potential wound healing activity of Greyia radlkoferi Szyszyl (GR) and its effect on growth factors regulating angiogenesis. The ethanolic leaf extract of GR was evaluated for antibacterial activity against wound associated bacteria; Staphylococcus aureus and Pseudomonas aeruginosa. It exhibited antibacterial activity against two strains of S. aureus (ATCC 25293 and ATCC 6538) displaying a minimum inhibitory concentration (MIC) at 250 and 500 μg/ml, respectively. The antioxidant activity of the extract was investigated for nitric oxide (NO) scavenging activity and showed a fifty percent inhibitory concentration (IC50) of 1266.5 ± 243.95 μg/ml. The extract was further investigated to determine its effect on the proliferation and modulation of growth factors secreted by human keratinocytes (HaCaT). Its effect on wound closure was evaluated using the scratch assay, where non-toxic concentrations were tested, as determined by the antiproliferative assay against HaCat cells (IC50 > 400 μg/ml). Results showed that the extract significantly inhibited wound closure, with a percentage closure of 60.15 ± 1.41% (p < 0.05) and 49.52 ± 1.43% (p < 0.01) at a concentration of 50 and 100 μg/ml, respectively, when compared to the 0.25% Dimethyl sulfoxide vehicle control (65.86 ± 1.12%). Quantification of secreted growth factors from cell-free supernatant, collected from the scratch assay, revealed that the extract significantly decreased the concentration of platelet-derived growth factor (PDGF-AA) at both 50 (p < 0.05) and 100 μg/ml (p < 0.001) (443.08 ± 77.36 and 178.98 ± 36.60 pg/ml) when compared to the 0.25% DMSO vehicle control (538.33 ± 12.64 pg/ml). Therefore, whilst the extract showed antibacterial activity against wound associated bacteria, it did not induce wound healing but rather showed a significant inhibition of wound closure, which was confirmed by the inhibition of PDGF-AA, a major growth factor involved in angiogenesis. Therefore, the GR extract, should be considered for further investigation of anti-angiogenic and anti-metastatic properties against cancer cells.

Suppression of histone deacetylase 1 by JSL-1 attenuates the progression and metastasis of cholangiocarcinoma via the TPX2/Snail axis

Histone deacetylases (HDACs) are entwined with the pathogenesis of various cancers and potentially serve as promising therapeutic targets. Herein, we intend to explore the potential role of HDAC1 inhibitor (JSL-1) in the tumorigenesis and metastasis of cholangiocarcinoma (CC) and to highlight the molecular basis of its function. As shown by bioinformatics analysis and immunohistochemical detection, high HDAC1 expression was witnessed in CC tissues relative to matched controls from patients with cholecystitis. The molecular network that HDAC1 silencing reduced the enrichment of HDAC1 and Snail on the TPX2 promoter was identified using immunoprecipitation and chromatin immunoprecipitation assays. Both short hairpin RNA (shRNA)-mediated knockdown of HDAC1 and JSL-1 treatment exhibited anti-proliferative, anti-migration and anti-invasion effects on CC cells through downregulation of TPX2. The in vivo xenograft model was developed in nude mice. Consistently, the anti-tumorigenic and anti-metastatic properties of shRNA against HDAC1 and HDAC1 inhibitor were validated in the in vivo settings. Taken together, our data supported the notion that HDAC1 inhibitor retards the initiation and development of CC via mediating the TPX2/Snail axis, highlighting the anti-tumor molecular network functioned in CC.

Cytotoxic and Radiosensitising Effects of a Novel Thioredoxin Reductase Inhibitor in Brain Cancers

The thioredoxin (Trx) system, a key antioxidant pathway, represents an attractive target for cancer therapy. This study investigated the chemotherapeutic and radiosensitising effects of a novel Trx reductase (TrxR) inhibitor, IQ10, on brain cancer cells and the underlying mechanisms of action. Five brain cancer cell lines and a normal cell type were used. TrxR activity and expression were assessed by insulin reduction assay and Western blotting, respectively. IQ10 cytotoxicity was evaluated using growth curve, resazurin reduction and clonogenic assays. Radiosensitivity was examined using clonogenic assay. Reactive oxygen species levels were examined by flow cytometry and DNA damage assessed by immunofluorescence. Epithelial-mesenchymal transition (EMT)-related gene expression was examined by RT-PCR array. IQ10 significantly inhibited TrxR activity but did not affect Trx system protein expression in brain cancer cells. The drug exhibited potent anti-proliferative and cytotoxic effects against brain cancer cells under both normoxic and hypoxic conditions in both 2D and 3D systems, with IC50s in the low micromolar range. It was up to ~ 1000-fold more potent than temozolomide. IQ10 substantially sensitised various brain cancer cells to radiation, with such effect being due, in part, to functional inhibition of TrxR, making cells less able to deal with oxidative stress and leading to increased oxidative DNA damage. IQ10 significantly downregulated EMT-associated gene expression suggesting potential anti-invasive and antimetastatic properties. This study suggests that IQ10 is a potent anticancer agent and could be used as either a single agent or combined with radiation, to treat brain cancers.