Parkin Enhances Gefitinib-induced Anoikis in HeLa Cervical Cancer Cells.

BACKGROUND/AIM: Gefitinib exhibits anticancer activity against cervical cancer cells via anoikis, a type of apoptosis induced by cell detachment from the extracellular matrix. Previous studies have reported that Parkin expression affects the efficacy of anticancer drugs. However, the impact of Parkin expression on the therapeutic effects of gefitinib in human cervical cancer remains unclear. Thus, this study aimed to evaluate whether Parkin over-expression improves the therapeutic effects of gefitinib against HeLa cervical cancer cells. MATERIALS AND METHODS: Cell viability and apoptotic death of HeLa cells were measured by trypan blue dye exclusion assay and flow cytometry. Cell detachment, adhesion, spreading, and cell-cell interaction were observed by inverted microscopy. Alteration of adhesion-related molecules was evaluated by confocal microscopy and western blot assay. RESULTS: Parkin expression potentiated gefitinib-induced cell detachment by affecting the organization of the actin cytoskeleton. In addition, Parkin expression induced a further reduction in the reattachment of and interaction between detached cells. The therapeutic efficacy of low-dose gefitinib combined with Parkin expression was equivalent to that of high-dose gefitinib alone. CONCLUSION: Parkin expression promotes gefitinib-induced anoikis, consequently increasing the efficacy of gefitinib against HeLa human cervical cancer cells. Based on our results, we propose that Parkin can be used to increase the anti-cancer effect of gefitinib on cervical cancer cells.

Synergistic effects of photodynamic therapy and chemotherapy: Activating the intrinsic/extrinsic apoptotic pathway of anoikis for triple-negative breast cancer treatment.

Triple-negative breast cancer (TNBC) is a highly invasive and metastatic subtype of breast cancer that often recurs after surgery. Herein, we developed a cyclodextrin-based tumor-targeted nano delivery system that incorporated the photosensitizer chlorin e6 (Ce6) and the chemotherapeutic agent lonidamine (LND) to form the R6RGD-CMßCD-se-se-Ce6/LND nanoparticles (RCC/LND NPS). This nanosystem could target cancer cells, avoid lysosomal degradation and further localize within the mitochondria. The RCC/LND NPS had pH and redox-responsive to control the release of Ce6 and LND. Consequently, the nanosystem had a synergistic effect by effectively alleviating hypoxia, enhancing the production of cytotoxic reactive oxygen species (ROS) and amplifying the efficacy of photodynamic therapy (PDT). Furthermore, the RCC/LND NPS + light weakened anoikis resistance, disrupted extracellular matrix (ECM), activated both the intrinsic apoptotic pathway (mitochondrial pathway) and extrinsic apoptotic pathway (receptor death pathway) of anoikis. In addition, the nanosystem showed significant anti-TNBC efficacy in vivo. These findings collectively demonstrated that RCC/LND NPS + light enhanced the anticancer effects, induced anoikis and inhibited tumor cell migration and invasion through a synergistic effect of chemotherapy and PDT. Overall, this study highlighted the promising potential of the RCC/LND NPS + light for the treatment of TNBC.

Lysophosphatidylcholine disrupts cell adhesion and induces anoikis in hepatocytes.

Lysophosphatidylcholine (LPC), the active metabolite of palmitate, triggers hepatocyte death by activating endoplasmic reticulum stress and JNK signalling-mediated lipoapoptosis. However, LPC-induced cytotoxicity in hepatocytes is not well understood. Here, we found for the first time that LPC-induced cell rounding occurred prior to apoptosis. LPC-induced rounding of cells reduced both cell-extracellular matrix (ECM) adhesion and cell-cell junctions, which promoted detachment-induced apoptosis (defined as anoikis) in hepatocytes. Further study revealed that LPC altered cellular morphology and cell adhesion by inhibiting integrin and cadherin signalling-mediated microfilament polymerization. We also found that ECM supplementation and microfilament cytoskeletal stabilization inhibited LPC-induced hepatocyte death by attenuating anoikis. Our data indicate a novel cytotoxic process and signalling pathway induced by LPC.

Cadmium induced Fak -mediated anoikis activation in kidney via nuclear receptors (AHR/CAR/PXR)-mediated xenobiotic detoxification pathway.

Cadmium (Cd) is a toxic heavy metal of considerable toxicity, possessing a serious environmental problem that threatening food safety and human health. However, the underlying mechanisms of Cd-induced nephrotoxicity and detoxification response remain largely unclear. Cd was administered at doses of 35, 70, and 140 mg/kg diet with feed for 90 days and produced potential damage to chickens' kidneys. The results showed that Cd exposure induced renal anatomical and histopathological injuries. Cd exposure up-regulated cytochrome P450 enzymes (CYP450s), activated nuclear xenobiotic receptors (NXRs) response, including aryl hydro-carbon receptor (AHR), constitutive androstane receptor (CAR), and pregnane X receptor (PXR) by low and moderate doses of Cd, and induced an increase in CYP isoforms expression. Cd exposure down-regulated phase II detoxification enzymes (glutathione-S-transferase (GST), glutathione peroxidase (GSH-PX) activities, and glutathione (GSH) content), and GST isoforms transcription . Furthermore, ATP-binding cassette (ABC) transporters, multidrug resistance protein (MRP1), and P-glycoprotein (P-GP) levels were elevated by low dose, but high dose inhibited the P-GP expression. Activation of detoxification enzymes lost their ability of resistance as increasing dose of Cd, afterwards brought into severe renal injury. Additionally, Cd suppressed focal adhesion kinase (Fak) and integrins protein expression as well as activated extrinsic pathway and intrinsic pathways, thereby producing anoikis. In conclusion, these results indicated that Cd induced Fak-mediated anoikis activation in the kidney via nuclear receptors (AHR/CAR/PXR)-mediated xenobiotic detoxification pathway.

The emerging role of miR-200 family in metastasis: focus on EMT, CSCs, angiogenesis, and anoikis.

INTRODUCTION: Cancer is the second major threat to human society and one of the main challenges facing healthcare systems. One of the main problems of cancer care is the metastases of cancer cells that cause 90% of deaths due to cancer. Multiple molecular mechanisms are involved in cancer cell metastasis. Therefore, a better understanding of these molecular mechanisms is necessary for designing restrictive strategies against cancer cell metastasis. Accumulating data suggests that MicroRNAs (miRNAs) are involved in metastasis and invasion of human tumors through regulating multiple genes expression levels that are involved in molecular mechanisms of metastasis. The goal of this review is to present the molecular pathways by which the miR 200 family manifests its effects on EMT, cancer stem cells, angiogenesis, anoikis, and the effects of tumor cell metastases. METHODS: A detailed literature search was conducted to find information about the role of the miR-200 family in the processes involved in metastasis in various databases. RESULTS: Numerous lines of evidence revealed an association between the mir-200 family and metastasis of human tumors by impressing processes such as cancer stem cells, EMT, angiogenesis, and anoikis. CONCLUSIONS: Understanding the molecular mechanisms associated with metastasis in which the miR-200 family is involved can be effective in treating metastatic cancers.

Epoxyazadiradione induced apoptosis/anoikis in triple-negative breast cancer cells, MDA-MB-231, by modulating diverse cellular effects.

Triple-negative breast cancer (TNBC) is one of the most aggressive forms of its kind, which accounts for 15-20% of all breast cancers. As this cancer form lacks hormone receptors, targeted chemotherapy remains the best treatment option. Apoptosis and anoikis (detachment-induced cell death) induction by small molecules can prevent TNBC metastasis to a greater extent. Epoxyazadiradione (EAD) is a limonoid from the neem plant with an anticancer property. Here, we demonstrate that EAD induced mitochondria-mediated apoptosis and anoikis in TNBC cells (MDA-MB-231). Apart from this, it promotes antimigration, inhibition of colony formation, downregulation of MMP-9 and fibronectin, induction of G2/M phase arrest with downregulation of cyclin A2/cdk2, interference in cellular metabolism, and inhibition of nuclear factor kappa-B (NF-kB) nuclear translocation. Moreover, a significant reduction is observed in the expression of EGFR on the plasma membrane and nucleus upon treatment with EAD. Among the diverse cellular effects, anoikis induction, metabolic interference, and downregulation of membrane/nuclear EGFR expression by EAD are reported here for the first time. To summarize, EAD targets multiple cellular events to induce growth arrest in TNBC, and hence can be developed into the best antineoplastic agent in the future.

Ursolic acid induces apoptosis and anoikis in colorectal carcinoma RKO cells.

BACKGROUND: Ursolic acid (UA) is an anti-cancer herbal compound. In the present study, we observed the effects of UA on anchorage-dependent and -independent growth of human colorectal cancer (CRC) RKO cells. METHODS: RKO cells were cultured in conventional and detached condition and treated with UA. Cell viability was evaluated by CCK-8 assay. Cell cycle was analyzed by flow cytometry. Apoptosis was identified by Hoechst 33258 staining and flow cytometry analysis. Activities of caspases were measured by commercial kits. Reactive oxygen species (ROS) was recognized by DCFH-DA fluorescent staining. Anoikis was identified by EthD-1 fluorescent staining and flow cytometry analysis. Expression and phosphorylation of proteins were analyzed by western blot. RESULTS: UA inhibited RKO cell viability in both a dose- and time-dependent manner. UA arrested the cell cycle at the G0/G1 phase, and induced caspase-dependent apoptosis. UA inhibited Bcl-2 expression and increased Bax expression. In addition, UA up-regulated the level of ROS that contributed to UA activated caspase-3, - 8 and - 9, and induced apoptosis. Furthermore, UA inhibited cell growth in a detached condition and induced anoikis in RKO cells that was accompanied by dampened phosphorylation of FAK, PI3K and AKT. UA also inhibited epithelial-mesenchymal transition (EMT) as indicated by the down-regulation of N-Cad expression and up-regulation of E-Cad expression. CONCLUSIONS: UA induced caspase-dependent apoptosis, and FAK/PI3K/AKT singling and EMT related anoikis in RKO cells. UA was an effective anti-cancer compound against both anchorage-dependent and -independent growth of RKO cells.

Kallistatin Inhibits Anoikis Resistance and Metastasis of Ectopic Endometrium Cells by Modulating MnSOD and Caspase 3 Signaling.

Endometriosis (EM) is a disease that involves active endometrial cell invasion and migration which is an important reason for infertility. Anoikis resistance is the most important prerequisite for EM, but the molecular mechanism is not yet clear. Kallistatin (KS) is one kind of serine protease inhibitors which had extensive biological function including anti-inflammatory, antioxidant stress, anti-angiogenesis, and anti-tumor. Our preliminary data showed that the level of KS in EM patients' endometrial tissue and blood were much lower than control (non-EM) patients without endometriosis. Interestingly, the decrease of KS is correlated with the severity of endometriosis. Moreover, kallistatin recombinant protein could increase the anoikis rate of ectopic endometrium cells (EESCs), and then inhibits its metastasis and invasion. Mechanically, our data show that the EESCs have lower intracellular reactive oxygen species (ROS) production and KS can elevate the ROS levels significantly. Further, KS modulate expression of MnSOD and caspase 3 signaling in EESCs grown in suspended conditions. These findings reveal novel mechanisms of KS in inducing anoikis and metastasis in EESCs, thus inhibiting EM progression by regulation of MnSOD and caspase 3 signaling. Our findings suggest that KS is a significant protein with prospects for application in EM.

Platelet­derived growth factor­BB mediates pancreatic cancer malignancy via regulation of the Hippo/Yes­associated protein signaling pathway.

Platelet­derived growth factor (PDGF) is a potent mitogen and chemoattractant that serves a role in the development of several types of solid cancer, and abnormal PDGF activity has been reported in numerous human tumors. Tumor­derived PDGF ligands are considered to act in either a paracrine or autocrine manner, serving roles in the phosphorylation of receptors on tumor and stromal cells in the tumor microenvironment. Despite the well­established association between PDGF and tumor progression, the precise mechanisms of autocrine PDGF signaling in pancreatic tumor cells remain elusive. Therefore, the present study aimed to analyze the influence of PDGF­BB in pancreatic cancer. Pancreatic adenocarcinoma BxPC­3 cells were cultured and treated with recombinant human PDGF­BB in vitro. Cell proliferation was tested using an MTT assay. Cell apoptosis was measured using flow cytometry. Tumor cell migration and invasion were examined via wound­healing and Transwell assays, respectively. The expression and subcellular localization of Yes­associated protein (YAP) was determined using western blotting and immunofluorescence. The transcriptional activity of target genes was tested using a luciferase assay and reverse transcription­quantitative PCR. The present study revealed that PDGF­BB significantly promoted cell proliferation in pancreatic adenocarcinoma BxPC­3 cells and enhanced the aggressiveness of this cell line, as demonstrated by Transwell and wound­healing assays. Anoikis resistance is an important mechanism by which metastatic cells avoid apoptosis when detaching from adjacent cells or the extracellular matrix. PDGF­BB treatment inhibited anoikis under anchorage­independent conditions. Mechanistic experiments revealed that PDGF­BB promoted the upregulation and activation of the transcriptional coactivator YAP, an effector of the Hippo signaling pathway. RhoA or protein phosphatase­1 (PP­1) inhibition partially abolished the accumulation and activation of YAP, suggesting PDGF­BB­mediated YAP dephosphorylation and transactivation via the RhoA/PP­1 cascade. Pharmacologic inhibition of the PDGF receptor directly downregulated YAP activity and the expression levels of downstream genes. Furthermore, verteporfin, a small molecular inhibitor of the Hippo/YAP signaling pathway, partially reversed the effects of PDGF­BB on cell proliferation, anoikis resistance and cell migration. In conclusion, the present study revealed that the Hippo/YAP signaling pathway may be involved in the tumor­promoting activity of PDGF­BB in pancreatic cancer.

Jinfukang regulates integrin/Src pathway and anoikis mediating circulating lung cancer cells migration.

ETHNOPHARMACOLOGICAL RELEVANCE: Metastasis is the main cause of death in lung cancer patients. Circulating tumor cells (CTCs) may be an important target of metastasis intervention. Previous studies have shown that Jinfukang could prevent the recurrence and metastasis of lung cancer, and we have established a circulating lung tumor cell line CTC-TJH-01. However, whether Jinfukang inhibition of lung cancer metastasis is related to CTCs is still unknown. AIM OF THE STUDY: To further explore the mechanism of Jinfukang in anti-metastasis of lung cancer from the perspective of intervention of CTCs. MATERIALS AND METHODS: CTC-TJH-01 and H1975 cells were treated with Jinfukang. Cell viability was detected by CCK8, and the cell apoptosis was detected by flow cytometry. Transwell was used to detected cell migration and invasion. Cell anoikis was detected by anoikis detection kit. Protein expression was analysis by Western blot. RESULTS: Jinfukang could inhibit the proliferation, migration and invasion of CTC-TJH-01 and H1975 cells. Besides, Jinfukang could also induce anoikis in CTC-TJH-01 and H1975 cells. Analysis of the mRNA expression profile showed ECM-receptor interaction and focal adhesion were regulated by Jinfukang. Moreover, it was also find that Jinfukang significantly inhibited integrin/Src pathway in CTC-TJH-01 and H1975 cells. When suppress the expression of integrin with ATN-161, it could promote Jinfukang to inhibit migration and induce anoikis in CTC-TJH-01 and H1975 cells. CONCLUSIONS: Our results indicate that the migration and invasion of CTCs are inhibited by Jinfukang, and the mechanism may involve the suppression of integrin/Src axis to induce anoikis. These data suggest that Jinfukang exerts anti-metastatic effects in lung cancer may through anoikis.

Implication of integrins α3ß1 and α5ß1 in invasion and anoikis of SK-Mel-147 human melanoma cells: non-canonical functions of protein kinase Akt.

Downregulation of integrins α3ß1 and α5ß1 strongly decreased cell colony formation and in vitro invasion and markedly enhanced anoikis in SK-Mel-147 human melanoma cells. These modifications were accompanied by a marked increase in the levels of active Akt protein kinase, which indicated it played a non-canonical function in the melanoma cells. Pharmacological inhibition of Akt1, an Akt isozyme, in cells depleted of α3ß1 or α5ß1 restored their invasive activity, while inhibition of the Akt 2 isoform did not cause a visible effect. Similar to our previous results with the α2ß1 integrin, this finding suggested that in signaling pathways initiated by α3ß1 and α5ß1, the Akt1 isoform performs a non-canonical function in regulating invasive phenotype of melanoma cells. In contrast, when the effects of Akt inhibitors on anoikis of the melanoma cells were compared, the Akt2 isoform demonstrated a non-canonical activity in which Akt2 suppression led to a significant attenuation of apoptosis in cells with downregulated α3ß1 or α5ß1. Our results were the first evidence that, in the same tumor cells, different integrins can control various manifestations of tumor progression through distinct signaling pathways that are both common to various integrins and specific to a particular receptor.

Pygenic Acid A (PA) Sensitizes Metastatic Breast Cancer Cells to Anoikis and Inhibits Metastasis In Vivo.

Metastasis is the main cause of cancer-related deaths. Anoikis is a type of apoptosis caused by cell detachment, and cancer cells become anoikis resistant such that they survive during circulation and can successfully metastasize. Therefore, sensitization of cancer cells to anoikis could prevent metastasis. Here, by screening for anoikis sensitizer using natural compounds, we found that pygenic acid A (PA), a natural compound from Prunella vulgaris, not only induced apoptosis but also sensitized the metastatic triple-negative breast cancer cell lines, MDA-MB-231 cells (human) and 4T1 cells (mouse), to anoikis. Apoptosis protein array and immunoblotting analysis revealed that PA downregulated the pro-survival proteins, including cIAP1, cIAP2, and survivin, leading to cell death of both attached and suspended cells. Interestingly, PA decreased the levels of proteins associated with anoikis resistance, including p21, cyclin D1, p-STAT3, and HO-1. Ectopic expression of active STAT3 attenuated PA-induced anoikis sensitivity. Although PA activated ER stress and autophagy, as determined by increases in the levels of characteristic markers, such as IRE1α, p-elF2α, LC3B I, and LC3B II, PA treatment resulted in p62 accumulation, which could be due to PA-induced defects in autophagy flux. PA also decreased metastatic characteristics, such as cell invasion, migration, wound closure, and 3D growth. Finally, lung metastasis of luciferase-labeled 4T1 cells decreased following PA treatment in a syngeneic mouse model when compared with the control. These data suggest that PA sensitizes metastatic breast cancer cells to anoikis via multiple pathways, such as inhibition of pro-survival pathways and activation of ER stress and autophagy, leading to the inhibition of metastasis. These findings suggest that sensitization to anoikis by PA could be used as a new therapeutic strategy to control the metastasis of breast cancer.

Intrahepatic metastases may be specific to hepatocellular carcinoma due to the coagulation and fibrinolytic systems (Review).

Hepatocellular carcinoma (HCC) is different from other solid tumors because it is commonly associated with the occurrence of intrahepatic metastasis. Additionally, the liver, unlike other organs, is the main site of coagulation and fibrinolytic factor production. Therefore, it was speculated that coagulation and fibrinolytic factors could be associated with intrahepatic metastasis of HCC. Do the coagulation and fibrinolytic systems protect HCC cells against anoikis during infiltration and metastasis? Conversely, do the coagulation and fibrinolytic systems lead to immune escape of HCC cells by affecting the immune microenvironment of patients? The current review aimed to present a number of novel hypotheses for the treatment of HCC by exploring the mechanisms of coagulation and fibrinolytic factors in the regulation of cancer growth.

Curcumol Suppresses Triple-negative Breast Cancer Metastasis by Attenuating Anoikis Resistance via Inhibition of Skp2-mediated Transcriptional Addiction.

BACKGROUND/AIM: Triple-negative breast cancer (TNBC) is a unique subtype that lacks expression of several conventional biomarkers and has a higher incidence of lymph node invasion and distal metastasis among all breast cancers. Anoikis resistance is the fundamental reason behind tumor cells' survival without their attachment to the extracellular matrix and metastasis to distal organs. Therefore, finding novel anti-cancer drugs that can suppress anoikis resistance in cancer cells is critical for patients with TNBC. MATERIALS AND METHODS: Curcumol, a natural compound, was used to assess whether it can inhibit the anoikis resistance and affects cell mortality and motility of IV2-1 TNBC cells. RESULTS: Curcumol suppressed anoikis resistance and inhibited TNBC cell survival in suspension. Additionally, these anti-cancer effects induced by curcumol could be related to the YAP1/Skp2 molecular pathway. CONCLUSION: Curcumol is an effective Skp2-targeted therapy that attenuates anoikis resistance and metastasis in TNBC cells.

Targeting an autocrine IL-6-SPINK1 signaling axis to suppress metastatic spread in ovarian clear cell carcinoma.

A major clinical challenge of ovarian cancer is the development of malignant ascites accompanied by widespread peritoneal metastasis. In ovarian clear cell carcinoma (OCCC), a challenging subtype of ovarian cancer, this problem is compounded by near-universal primary chemoresistance; patients with advanced stage OCCC thus lack effective therapies and face extremely poor survival rates. Here we show that tumor-cell-expressed serine protease inhibitor Kazal type 1 (SPINK1) is a key driver of OCCC progression and metastasis. Using cell culture models of human OCCC, we find that shRNA silencing of SPINK1 sensitizes tumor cells to anoikis and inhibits proliferation. Knockdown of SPINK1 in OCCC cells also profoundly suppresses peritoneal metastasis in mouse implantation models of human OCCC. We next identify a novel autocrine signaling axis in OCCC cells whereby tumor-cell-produced interleukin-6 (IL-6) regulates SPINK1 expression to stimulate a common protumorigenic gene expression pattern leading to anoikis resistance and proliferation of OCCC cells. We further demonstrate that this signaling pathway can be successfully interrupted with the IL-6Rα inhibitor tocilizumab, sensitizing cells to anoikis in vitro and reducing metastasis in vivo. These results suggest that clinical trials of IL-6 pathway inhibitors in OCCC may be warranted, and that SPINK1 might offer a candidate predictive biomarker in this population.

Ophiopogonin D suppresses TGF-ß1-mediated metastatic behavior of MDA-MB-231 breast carcinoma cells via regulating ITGB1/FAK/Src/AKT/ß-catenin/MMP-9 signaling axis.

Ophiopogonin D, a steroidal glycoside extracted from the Traditional Chinese Medicine Ophiopogon japonicus, shows anti-tumor property in several lines of cancers; however, its effect on triple-negative breast cancer (TNBC) has not been investigated. In this study, the anti-metastatic effect of Ophiopogonin D in TNBC cells as well as the underlying mechanism in such process was explored. Ophiopogonin D dose-dependently decreased cell proliferation of MDA-MB-231 cells. Meanwhile, Ophiopogonin D significantly inhibited TGF-ß1-induced metastatic behavior of MDA-MB-231 cells, including EMT, anoikis resistance as well as migration and invasion, via suppressing MMP-9 activity. Mechanically, Ophiopogonin D achieved its effect through efficiently abolishing ITGB1 expression, thus reducing the phosphorylation of FAK, Src and AKT, as well as upregulating nuclear ß-catenin. ITGB1 overexpression partly recovered Ophiopogonin D's inhibitory effect on metastatic behavior via activating MMP-9. These results demonstrated that Ophiopogonin D could suppress TGF-ß1-mediated metastatic behavior of MDA-MB-231 cells by regulating ITGB1/FAK/Src/AKT/ß-catenin/MMP-9 signaling axis, which might provide new insight for the control of TNBC metastasis.

Nuclear MYH9-induced CTNNB1 transcription, targeted by staurosporin, promotes gastric cancer cell anoikis resistance and metastasis.

Rationale: Peritoneal metastasis predicts poor prognosis of gastric cancer (GC) patients, and the underlying mechanisms are poorly understood. Methods: The 2-DIGE, MALDI-TOF/TOF MS and single-cell transcriptome were used to detect differentially expressed proteins among normal gastric mucosa, primary GC and peritoneal metastatic tissues. Lentiviruses carrying shRNA and transcription activator-like effector nuclease technology were used to knock down myosin heavy chain 9 (MYH9) expression in GC cell lines. Immunofluorescence, immune transmission electron microscopy, chromatin fractionation, co-immunoprecipitation, and assays for chromatin immunoprecipitation, dual luciferase reporter, agarose-oligonucleotide pull-down, flow cytometry and cell anoikis were performed to uncover nuclear MYH9-induced ß-catenin (CTNNB1) transcription in vitro. Nude mice and conditional transgenic mice were used to investigate the findings in vivo. Results: We observed that MYH9 was upregulated in metastatic GC tissues and was associated with a poor prognosis of GC patients. Mechanistically, we confirmed that MYH9 was mainly localized in the GC cell nuclei by four potential nuclear localization signals. Nuclear MYH9 bound to the CTNNB1 promoter through its DNA-binding domain, and interacted with myosin light chain 9, ß-actin and RNA polymerase II to promote CTNNB1 transcription, which conferred resistance to anoikis in GC cells in vitro and in vivo. Staurosporine reduced nuclear MYH9 S1943 phosphorylation to inhibit CTNNB1 transcription, Wnt/ß-catenin signaling activation and GC progression in both orthotropic xenograft GC nude mouse and transgenic GC mouse models. Conclusion: This study identified that nuclear MYH9-induced CTNNB1 expression promotes GC metastasis, which could be inhibited by staurosporine, indicating a novel therapy for GC peritoneal metastasis.

Rapha Myr®, a Blend of Sulforaphane and Myrosinase, Exerts Antitumor and Anoikis-Sensitizing Effects on Human Astrocytoma Cells Modulating Sirtuins and DNA Methylation.

Brain and other nervous system cancers are the 10th leading cause of death worldwide. Genome instability, cell cycle deregulation, epigenetic mechanisms, cytoarchitecture disassembly, redox homeostasis as well as apoptosis are involved in carcinogenesis. A diet rich in fruits and vegetables is inversely related with the risk of developing cancer. Several studies report that cruciferous vegetables exhibited antiproliferative effects due to the multi-pharmacological functions of their secondary metabolites such as isothiocyanate sulforaphane deriving from the enzymatic hydrolysis of glucosinolates. We treated human astrocytoma 1321N1 cells for 24 h with different concentrations (0.5, 1.25 and 2.5% v/v) of sulforaphane plus active myrosinase (Rapha Myr®) aqueous extract (10 mg/mL). Cell viability, DNA fragmentation, PARP-1 and γH2AX expression were examined to evaluate genotoxic effects of the treatment. Cell cycle progression, p53 and p21 expression, apoptosis, cytoskeleton morphology and cell migration were also investigated. In addition, global DNA methylation, DNMT1 mRNA levels and nuclear/mitochondrial sirtuins were studied as epigenetic biomarkers. Rapha Myr® exhibited low antioxidant capability and exerted antiproliferative and genotoxic effects on 1321N1 cells by blocking the cell cycle, disarranging cytoskeleton structure and focal adhesions, decreasing the integrin α5 expression, renewing anoikis and modulating some important epigenetic pathways independently of the cellular p53 status. In addition, Rapha Myr® suppresses the expression of the oncogenic p53 mutant protein. These findings promote Rapha Myr® as a promising chemotherapeutic agent for integrated cancer therapy of human astrocytoma.

Benzoxazine Dimer Analogue Targets Integrin ß3 in Lung Cancer Cells and Suppresses Anoikis Resistance and Migration.

BACKGROUND/AIM: Certain integrins including integrin ß3 facilitate movement and survival of metastatic cancer cells. We examined whether benzoxazine dimer analogue N,N-bis(5-ethyl-2-hydroxybenzyl) methylamine (HM) has anti-metastatic effects. MATERIALS AND METHODS: Cell viability was examined by the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Wound healing and phalloidin-rhodamine assays were performed to evaluate the migration and filopodia formation, respectively. Anoikis resistance was studied by anchorage-independent growth assay. The expression of proteins regulating migration were examined by western blot. RESULTS: HM treatment significantly inhibited growth and survival of detached lung cancer cells as indicated by the reduced colony number and size of anchorage-independent growth analysis. HM inhibited cell migration and suppressed filopodia formation. Protein analysis indicated that the compound dramatically decreased integrin ß3 and its related downstream proteins including active focal adhesion kinase (FAK) and active protein kinase B (AKT); however, integrin ß1 and α5 were found to be unaltered. CONCLUSION: HM shows a potential in targeting integrin ß3 and could be a good candidate for further developed as an anti-metastatic therapy.

Dexamethasone Inhibits Spheroid Formation of Thyroid Cancer Cells Exposed to Simulated Microgravity.

Detachment and the formation of spheroids under microgravity conditions can be observed with various types of intrinsically adherent human cells. In particular, for cancer cells this process mimics metastasis and may provide insights into cancer biology and progression that can be used to identify new drug/target combinations for future therapies. By using the synthetic glucocorticoid dexamethasone (DEX), we were able to suppress spheroid formation in a culture of follicular thyroid cancer (FTC)-133 cells that were exposed to altered gravity conditions on a random positioning machine. DEX inhibited the growth of three-dimensional cell aggregates in a dose-dependent manner. In the first approach, we analyzed the expression of several factors that are known to be involved in key processes of cancer progression such as autocrine signaling, proliferation, epithelial-mesenchymal transition, and anoikis. Wnt/ß-catenin signaling and expression patterns of important genes in cancer cell growth and survival, which were further suggested to play a role in three-dimensional aggregation, such as NFKB2, VEGFA, CTGF, CAV1, BCL2(L1), or SNAI1, were clearly affected by DEX. Our data suggest the presence of a more complex regulation network of tumor spheroid formation involving additional signal pathways or individual key players that are also influenced by DEX.