Stemness and chromosomal instability (CIN) are two common contributors to intratumor heterogeneity and therapy relapse in advanced cancer, but their interplays are poorly defined. Here, in anaplastic ...thyroid cancer (ATC), we show that ALDH+ stem-like cancer cells possess increased CIN-tolerance owing to transcriptional upregulation of the scaffolding protein NEDD9. Thyroid patient tissues and transcriptomic data reveals NEDD9/ALDH1A3 to be co-expressed and co-upregulated in ATC. Compared to bulk ALDH- cells, ALDH+ cells were highly efficient at propagating CIN due to their intrinsic tolerance of both centrosome amplification and micronuclei. ALDH+ cells mitigated the fitness-impairing effects of centrosome amplification by partially inactivating supernumerary centrosomes. Meanwhile, ALDH+ cells also mitigated cell death caused by micronuclei-mediated type 1 interferon secretion by suppressing the expression of the DNA-sensor protein STING. Both mechanisms of CIN-tolerance were lost upon RNAi-mediated NEDD9 silencing. Both in vitro and in vivo, NEDD9-depletion attenuated stemness, CIN, cell/tumor growth, while enhancing paclitaxel effectiveness. Collectively, these findings reveal that ATC progression can involve an ALDH1A3/NEDD9-regulated program linking their stemness to CIN-tolerance that could be leveraged for ATC treatment.
Melanoma can be stratified into unique subtypes based on distinct pathologies. The acral/mucosal melanoma subtype is characterized by aberrant and constitutive activation of the proto-oncogene ...receptor tyrosine kinase C-KIT, which drives tumorigenesis. Treatment of these melanoma patients with C-KIT inhibitors has proven challenging, prompting us to investigate the downstream effectors of the C-KIT receptor. We determined that C-KIT stimulates MAP kinase-interacting serine/threonine kinases 1 and 2 (MNK1/2), which phosphorylate eukaryotic translation initiation factor 4E (eIF4E) and render it oncogenic. Depletion of MNK1/2 in melanoma cells with oncogenic C-KIT inhibited cell migration and mRNA translation of the transcriptional repressor SNAI1 and the cell cycle gene CCNE1. This suggested that blocking MNK1/2 activity may inhibit tumor progression, at least in part, by blocking translation initiation of mRNAs encoding cell migration proteins. Moreover, we developed an MNK1/2 inhibitor (SEL201), and found that SEL201-treated KIT-mutant melanoma cells had lower oncogenicity and reduced metastatic ability. Clinically, tumors from melanoma patients harboring KIT mutations displayed a marked increase in MNK1 and phospho-eIF4E. Thus, our studies indicate that blocking MNK1/2 exerts potent antimelanoma effects and support blocking MNK1/2 as a potential strategy to treat patients positive for KIT mutations.
The present study reports synthesis and biological activity of novel benzoisoselenazolone compounds derived from ebselen and conjugated to a sugar molecule. Cell proliferation assay using cancer ...cells combined with
in vitro biochemical assays revealed that benzoisoselenazolone
2d,
5a, and
6a exerted anti-proliferative activity, which correlated with selective
in vitro inhibition of focal adhesion kinase, AKT-1, and protein kinase C-α. Active molecules were able to significantly inhibit cell migration and invasion
in vitro compared to cells treated with the vehicle alone or ebselen. Moreover,
in vivo anticancer activity focusing on lead compound
2d and using an invasive human breast cancer orthotopic mouse model revealed a potent anti-metastatic activity at well-tolerated doses. In summary, these novel benzoisoselenazolones we report herein target multiple kinases with established roles in cancer progression and possess anti-invasive and anti-metastatic activity in preclinical models supporting a potential for therapeutic application for human disease.
Novel benzisoselenazolone derivatives that possess significant anticancer activity
in vitro and
in vivo.
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► Novel sugar conjugated benzisoselenazolone derivatives have been synthesized. ► Possess significant anti-invasive and anti-metastatic breast cancer activity. ► Selectively inhibits FAK, AKT-1 and PKC-α kinases.
Invasive oral squamous cell carcinoma (OSCC) is often ulcerated and heavily infiltrated by pro-inflammatory cells. We conducted a genome-wide profiling of tissues from OSCC patients (early versus ...advanced stages) with 10 years follow-up. Co-amplification and co-overexpression of
, a transcriptional activator of epithelial-mesenchymal-transition (EMT), and colony-stimulating factor-1 (
), a major chemotactic agent for tumor-associated macrophages (TAMs), were observed in metastatic OSCC cases. The overexpression of these markers strongly predicted poor patient survival (log-rank test,
= 0.0035 and
= 0.0219). Protein analysis confirmed the enhanced expression of TWIST1 and CSF1 in metastatic tissues. In preclinical models using OSCC cell lines, macrophages, and an in vivo matrigel plug assay, we demonstrated that
gene overexpression induces the activation of
while
gene silencing down-regulates
preventing OSCC invasion. Furthermore, excessive macrophage activation and polarization was observed in co-culture system involving OSCC cells overexpressing
. In summary, this study provides insight into the cooperation between
transcription factor and
to promote OSCC invasiveness and opens up the potential therapeutic utility of currently developed antibodies and small molecules targeting cancer-associated macrophages.
Purpose: Prostate cancer metastasis to secondary organs is considered an initial event in the development of hormone refractory disease
and remains the major cause of death among prostate cancer ...patients. In this study, we investigated the role of fascin, a
cytoskeleton actinâbundling protein involved in the formation of filopodia and cell migration, in prostate cancer progression.
Experimental Design: Fascin protein expression was examined by immunohistochemistry in a cohort of 196 patients with localized prostate cancer
and across several stages of disease progression, including hormone refractory disease. Cellular changes were also assessed
in vitro and in vivo in DU145 prostate cancer cell line using fascin gene silencing.
Results: Fascin epithelial expression was significantly up-regulated in localized and hormone refractory prostate cancer compared
with benign prostate tissue ( P < 0.05). Furthermore, high fascin expression was associated with an increased rate of prostate-specific antigen recurrence
following radical prostatectomy ( P = 0.075), signifying more aggressive clinical course, thus supporting a function for fascin in prostate cancer progression.
In cellular models, fascin gene silencing using small interfering RNA in the androgen-independent prostate cancer cell line
DU145 decreased cell motility and invasiveness while increasing cell adhesive properties. In addition, fascin small interfering
RNAâexpressing DU145 cells implanted orthotopically in mouse prostate showed significantly decreased growth ( P < 0.005) and drastically prevented the formation of lymph node metastases ( P < 0.001) compared with their matched controls.
Conclusions: Our data show a function of fascin in the regulation of prostate cancer progression and emphasize the importance of fascin
as a prognostic marker for aggressive disease and as a potential therapeutic target for advanced androgen independent disease.
C5b-9-induced glomerular epithelial cell (GEC) injury in vivo (in passive Heymann nephritis) and in culture is associated with damage to the endoplasmic reticulum (ER) and increased expression of ER ...stress proteins. Induction of ER stress proteins is enhanced via cytosolic phospholipase A2 (cPLA2) and limits complement-dependent cytotoxicity. The present study addresses another aspect of the ER unfolded protein response, i.e. activation of protein kinase R-like ER kinase (PERK or pancreatic ER kinase), which phosphorylates eukaryotic translation initiation factor 2-α (eIF2α), thereby generally suppressing translation and decreasing the protein load on a damaged ER. Phosphorylation of eIF2α was enhanced significantly in glomeruli of proteinuric rats with passive Heymann nephritis, compared with control. In cultured GECs, complement induced phosphorylation of eIF2α and reduced protein synthesis, and complement-stimulated phosphorylation of eIF2α was enhanced by overexpression of cPLA2. Ischemia-reperfusion in vitro (deoxyglucose plus antimycin A followed by glucose re-exposure) also stimulated eIF2α phosphorylation and reduced protein synthesis. Complement and ischemia-reperfusion induced phosphorylation of PERK (which correlates with activation), and fibroblasts from PERK knock-out mice were more susceptible to complement- and ischemia-reperfusion-mediated cytotoxicity, as compared with wild type fibroblasts. The GEC protein, nephrin, plays a key role in maintaining glomerular permselectivity. In contrast to a general reduction in protein synthesis, translation regulated by the 5′-end of mouse nephrin mRNA during ER stress was paradoxically maintained, probably due to the presence of short open reading frames in this mRNA segment. Thus, phosphorylation of eIF2α and consequent general reduction in protein synthesis may be a novel mechanism for limiting complement- or ischemia-reperfusion-dependent GEC injury.
Papillary thyroid carcinoma (PTC) is the most common malignancy of the thyroid gland and early stages are curable. However, a subset of PTCs shows an unusually aggressive phenotype with extensive ...lymph node metastasis and higher incidence of locoregional recurrence. In this study, we investigated a large cohort of PTC cases with an unusual aggressive phenotype using a high-throughput RNA sequencing (RNA-Seq) to identify differentially regulated genes associated with metastatic PTC. All metastatic PTC with mutated BRAF (V600E) but not BRAF wild-type expressed an up-regulation of R-Spondin Protein 4 (RSPO4) concomitant with an upregulation of genes involved in focal adhesion and cell-extracellular matrix signaling. Further immunohistochemistry validation confirmed the upregulation of these target genes in metastatic PTC cases. Preclinical studies using established PTC cell lines support that RSPO4 overexpression is associated with BRAF V600E mutation and is a critical upstream event that promote activation of kinases of focal adhesion signaling known to drive cancer cell locomotion and invasion. This finding opens up the potential of co-targeting B-Raf, RSPO and focal adhesion proteins as a pharmacological approach for aggressive BRAF V600E PTC.
Early cancer cell migration and invasion of neighboring tissues are mediated by multiple events, including activation of focal adhesion signaling. Key regulators include the focal adhesion kinase ...(FAK) and FAK-related proline-rich tyrosine kinase 2 (Pyk2), whose distinct functions in cancer progression remain unclear. Here, we compared Pyk2 and FAK expression in breast cancer and their effects on ErbB-2-induced tumorigenesis and the potential therapeutic utility of targeting Pyk2 compared with FAK in preclinical models of breast cancer. Pyk2 is overexpressed in tissues from early and advanced breast cancers and overexpressed with both FAK and epidermal growth factor receptor-2 (ErbB-2) in a subset of breast cancer cases. Down-regulation of Pyk2 in ErbB-2-positive, FAK-proficient, and FAK-deficient cells reduced cell proliferation, which correlated with reduced mitogen-activated protein kinase (MAPK) activity. In contrast, Pyk2 silencing had little impact on cell migration and invasion. In vivo , Pyk2 down-regulation reduced primary tumor growth induced by a metastatic variant of ErbB-2-positive MDA 231 breast cancer cells but had little effect on lung metastases in contrast to FAK down-regulation. Dual reduction of Pyk2 and FAK expression resulted in strong inhibition of both primary tumor growth and lung metastases. Together, these data support the cooperative function of Pyk2 and FAK in breast cancer progression and suggest that dual inhibition of FAK and Pyk2 is an efficient therapeutic approach for targeting invasive breast cancer.
Eudistomin Y class compounds are a series of β-carbolines which was originally isolated from a marine turnicate or ascidian near the South Korea Sea. These compounds contain bromo-substituted groups, ...which is one of the typical characters of marine natural products. We report herein the chemical synthesis and biological evaluation of seven new β-carboline-based metabolites, Eudistomins Y1-Y7, and their hydroxyl-methylated phenyl derivatives. Using bromo-substituted tryptamines and bromo-substituted phenylglyoxals as the key intermediates, Eudistomins Y1-Y7 and their derivatives were synthesized via the acid-catalyzed Pictet-Spengler reaction and fully characterized by 1H- and 13C-NMR and mass spectroscopy. Biological studies revealed that all of the compounds showed moderate growth inhibitory activity against breast carcinoma cell line MDA-231 with IC50 of 15-63 μM and the inhibitory activities of hydroxyl-methylated phenyl products were higher than that of the corresponding natural products Eudistomins Y1-Y7.
Focal segmental glomerulosclerosis (FSGS) may be associated with glomerular epithelial cell (GEC; podocyte) apoptosis due to acquired injury or mutations in specific podocyte proteins. This study ...addresses mediation of GEC injury, focusing on endoplasmic reticulum (ER) stress. We studied signaling in cultured GECs in the presence or absence of the extracellular matrix (ECM). Adhesion to collagen supports cell survival, but adhesion to plastic (loss of contact with ECM) leads to apoptosis. Compared with collagen-adherent cells, GECs on plastic showed increased protein misfolding in the ER, and an adaptive-protective ER stress response, including increased expression of ER chaperones, increased phosphorylation of eukaryotic translation initiation factor-2α (eIF2α), and a reduction in protein synthesis. Activation of these ER stress pathways counteracted apoptosis. However, tunicamycin (a potent stimulator of ER stress) changed the ER stress response from protective to cytotoxic, as tunicamycin induced the proapoptotic ER stress gene, C/EBP homologous protein-10, and exacerbated apoptosis in GECs adherent to plastic, but not collagen. In GECs adherent to plastic, adaptive ER stress was associated with an increase in polyubiquitinated proteins and "choking" of the proteasome. Furthermore, pharmacological inhibition of the proteasome induced ER stress in GECs. Finally, we show that ER stress (induction of ER chaperones and eIF2α phosphorylation) was evident in experimental FSGS in vivo. Thus interactions of GECs with ECM may regulate protein folding and induction of the ER stress response. FSGS is associated with induction of ER stress. Enhancing protective aspects of the ER stress response may reduce apoptosis and possibly glomerulosclerosis.
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