BACKGROUND:Homoharringtonine (HHT) is a purified alkaloid compound isolated from the plant Cephalotaxus, traditionally used in Chinese medicine for various ailments, including leukemia. However, the specific role and biological mechanisms by which HHT regulates metastasis in pancreatic cancer (PC) remain unclear. PC is notorious for its high metastatic potential, yet our understanding of the molecular mechanisms driving its metastasis is still limited. The primary aim of this study is to explore the antimetastatic potential of HHT in PC and elucidate its mechanism of inhibiting epithelial-mesenchymal transition (EMT) via EphB4 and SRI. MATERIALS AND METHODS:Western blotting, RT-qPCR, immunofluorescence, and transfection of overexpression and shRNA vectors were employed to examine the expression levels of metastatic factors. Antimetastatic activities were evaluated using scratch and transwell assays. In vitro experiments were complemented by in vivo investigations, supported by immunohistochemistry. RESULTS:We identify a distinct molecular mechanism governing migration, invasion, and metastasis in PC through the EphB4/SRI/EMT pathway. Upregulation of EphB4 increased SRI expression, thereby promoting EMT-associated migration and invasion. A direct interaction between EphB4 and SRI facilitated EMT progression and cellular migration. HHT inhibited EphB4, leading to the downregulation of SRI and reversal of EMT-related markers (E-cadherin and N-cadherin). Moreover, HHT enhanced the antimetastatic effects of erlotinib (ERT) in both in vitro and in vivo PC models. DISCUSSION:The EphB4/SRI/EMT axis emerges as a novel regulatory pathway in PC metastasis, with EphB4 directly interacting with SRI to promote EMT and metastatic behavior. This discovery expands our understanding of the molecular networks driving PC progression, highlighting EphB4 and SRI as potential therapeutic targets. HHT, previously recognized for its antileukemic activity, is shown here to target this axis, reverse EMT, and reduce metastasis. Additionally, the synergistic effect of HHT with ERT suggests a promising combinatorial strategy to overcome the limitations of single-agent targeted therapy, particularly in addressing drug resistance in advanced PC. CONCLUSION:HHT has been identified as an impediment to cell invasion and metastasis in PC via the EphB4/SRI/EMT axis. Additionally, HHT enhances the efficacy of ERT in inhibiting the migration of PC cells.
Background Vorinostat (SAHA) is a histone deacetylase inhibitor that has shown clinical efficacy against advanced cutaneous T-cell lymphoma (CTCL). However, only a subset of patients with CTCL (30–35%) respond to SAHA and the response is not always sustainable. Thus, understanding the mechanisms underlying evasive resistance in this cancer is an unmet medical need to improve the efficacy of current therapies.Purpose This study aims to identify factors contributing to resistance against SAHA in CTCL and ways to mitigate it.Methods and results In this study, we demonstrated that attenuated reactive oxygen species (ROS) induces the expression of interleukin (IL)-2Rα, one of the IL-2 receptors, which drives resistance to SAHA in CTCL. We also determined that cantharidin could overcome SAHA resistance to CTCL by blocking IL-2Rα-related signaling via ROS-dependent manner. Mechanistically, accelerated translation of IL-2Rα contributes to excessive IL-2Rα protein formation as a result of reduced ROS levels in SAHA-resistant CTCL. At the same time, amplified IL-2R signals are evidenced by strengthened interaction of IL-2Rβ with IL-2Rγ and Janus kinase/signal transducer and activator of transcription molecules, and by increased expression of protein kinase B (AKT)/mTOR and mitogen-activated protein kinase signaling. Moreover, cantharidin, an active constituent of Mylabris used in traditional Chinese medicine, markedly increased ROS levels, and thereby restrained IL-2Rα translation, resulting in suppression of downstream pathways in SAHA-resistant cells. Cantharidin is also found to synergize with SAHA and triggers SAHA-resistant cell death via IL-2R signaling both in vitro and in vivo.Conclusion Our study uncovers a novel molecular mechanism of acquired SAHA resistance and also suggests that using cantharidin is a potential approach to overcome CTCL therapy resistance. Our findings underlie the therapeutic potential of cantharidin in treating CTCL.
Non-small cell lung cancer (NSCLC) is a highly malignant tumor with a poor prognosis. Hypoxia conditions affect multiple cellular processes promoting the adaptation and progression of cancer cells via the activation of hypoxia-inducible factors (HIF) and subsequent transcription activation of their target genes. Preliminary studies have suggested that estrogen receptor β (ERβ) might play a promoting role in the progression of NSCLC. However, the precise mechanisms, particularly its connection to HIF-1α-mediated modulation under hypoxia, remain unclear. Our findings demonstrated that the overexpression of ERβ, not ERα, increased cell proliferation and inhibition of apoptosis in NSCLC cells and xenografts. Tissue microarray staining revealed a strong correlation between the protein expression of HIF-1α and ERβ. HIF-1α induced ERβ gene transcription and protein expression in CoCl2-induced hypoxia, 1
Parkin (PARK2) deficiency is frequently observed in various cancers and potentially promotes tumor progression. Here, we showed that Parkin expression is downregulated in liver cancer tissues, which correlates with poor patient survival. Parkin deficiency in liver cancer cells promotes migration and metastasis as well as changes in EMT and metastasis markers. A negative correlation exists between TMEFF1 and Parkin expression in liver cancer cells and tumor tissues. Parkin deficiency leads to upregulation of TMEFF1 which promotes migration and metastasis. TMEFF1 transcription is activated by Parkin-induced endogenous TGF-β production and subsequent phosphorylation of Smad2/3 and its binding to TMEFF1 promotor. TGF-β inhibitor and TMEFF1 knockdown can reverse shParkin-induced cell migration and changes of EMT markers. Parkin interacts with and promotes the ubiquitin-dependent degradation of HIF-1α/HIF-1β and p53, which accounts for the suppression of TGF-β production. Our data have revealed that Parkin deficiency in cancer leads to the activation of the TGF-β/Smad2/3 pathway, resulting in the expression of TMEFF1 which promotes cell migration, EMT, and metastasis in liver cancer cells.
Introduction: Tumor-associated calcium signal transducer 2 (Trop2) has been used as a transport gate for cytotoxic agents into cells in antibody-drug conjugate designs because of its expression in a wide range of solid tumors. However, the specific role of Trop2 itself in breast cancer progression remains unclear and small molecules targeting Trop2 have not yet been reported. Objectives: To screen small molecules targeting Trop2, and to reveal its pharmacological effects and the molecular mechanisms of action. Methods: Small molecule targeting Trop2 was identified by cell membrane chromatography, and validated by cellular thermal shift assay and point mutation analyses. We investigated the pharmacological effects of Trop2 inhibitor using RNA-seq, human foreskin fibroblast (HFF)-derived extracellular matrix (ECM), Matrigel drop invasion assays, colony-forming assay, xenograft tumor model, 4T1 orthotopic metastasis model and 4T1 experimental metastasis model. The molecular mechanism was determined using immunoprecipitation, mass spectrometry, immunofluorescence, immunohistochemistry and Western blotting.
OBJECTIVES To investigate the anticancer effect of Pingxiao capsule (, PXC) on the treatment of breast cancer and . METHODS The inhibition of PXC on cell viability and proliferation was determined by cell counting kit-8, EdU assay and colony formation assay, respectively. The effect of PXC on cell apoptosis was detected by using flow cytometry. The suppression of PXC on cell migration and invasion was investigated by chamber assay. To investigate the underlying molecular mechanisms, the expression of proteins related to epithelial to mesenchymal transition (EMT) was analyzed by Western blotting in breast cancer cells and by immunohistochemistry in tumor tissues. The anticancer effect of PXC was evaluated by using MDA-MB-231 xenograft model and 4T1 metastatic breast cancer model. RESULTS Our results indicated that triple-negative breast cancer (TNBC) cell lines MDA-MB-231 and MDA-MB-468 were sensitive to PXC. PXC potently inhibited the proliferation, colony formation, migration, and invasion of MDA-MB-231 and MDA-MB-468 cells . Then, MDA-MB-231 xenograft model depicted that PXC significantly reduced tumor size and weight compared with Control. 4T1 lung metastasis model showed that PXC significantly inhibited breast cancer cell spreading to lungs in mice. Mechanistically, PXC inhibited EMT process by reducing cadherin turnover in TNBC. Furthermore, PXC in combination with 8 Gy X-ray treatment obviously promoted the induction of apoptosis, and suppressed cell proliferation. CONCLUSION PXC could inhibit the proliferation and invasion of TNBC both and , and exerted its anti-metastatic effect by regulating cadherin turnover, Furthermore, it sensitized the TNBC cells to radiotherapy. The data supported further development of PXC as an adjuvant-therapy agent for TNBC.
OBJECTIVES:Pancreatic cancer (PC) is a very lethal malignancy with a scarcity of treatment options. Although erlotinib- and gemcitabine-based treatments have been approved for PC, their effectiveness is limited. The present study is aimed at exploring the molecular and epigenetic mechanisms of anticancer activities of homoharringtonine (HHT) and its interaction with erlotinib to develop a potential therapeutic strategy for PC.METHODS:The RT-qPCR, western blotting, immunofluorescence and expression-vectors and oligonucleotide transfection were employed to determine the expression characteristics of onco-factors. Anticancer activities were determined by MTT, colony forming, and flowcytometric analysis. Dual luciferase assay was conducted to confirm putative target of miR-130b-3p. In-vivo experiments were followed by immunohistochemical assay.KEY FINDINGS:The EphB4/JAK2/STAT3 pathway drives the growth and proliferation of PC through induction of prosurvival factors and cell cycle mediators. HHT directly and epigenetically via miR-130b-3p targets EphB4, leading to downregulation of JAK2/STAT3 pathway. The inactivation of STAT3 results in diminution of antiapoptotic factors and cell cycle mediators. HHT also enhances the anticancer activity of erlotinib.CONCLUSIONS:HHT demonstrates potential anticancer activities in PC by downregulating EphB4/JAK2/STAT3 signalling. HHT also produces synergistic effects with erlotinib.
The host stimulator of interferon genes (STING) signaling pathway is a major innate immune sensing pathway, and the stimulation of this pathway within antigen-presenting cells shows promise in targeting immune-suppressed tumors. Macrophages resident in tumors exhibit anti-inflammatory properties and enhance tumor growth and development. Polarizing such macrophages towards a pro-inflammatory phenotype is an effective strategy for tumor suppression. In the present study, we observed that the STING pathway was inactivated in breast and lung carcinomas, and a positive correlation existed between STING and macrophage markers in these tumors. We found that vanillic acid (VA) could stimulate the STING/TBK1/IRF3 pathway. VA mediated the production of type I IFN and promoted macrophage polarization into the M1 phenotype; this activity was dependent on STING activation. A direct-contact co-culture model and a transwell co-culture model revealed that macrophages with VA-induced STING activation exhibited anti-proliferative effects on SKBR3 and H1299 cells, although a STING antagonist and M2 macrophage-related cytokines alleviated this anti-proliferative effect. Further investigation indicated that phagocytosis and apoptosis-inducing effects were the major mediators of the anti-tumor effect of VA-treated macrophages. Mechanistically, VA promoted the polarization of macrophages to a M1 phenotype via IL-6R/JAK signaling, resulting in enhanced phagocytosis and apoptosis-induction effects. Additionally, STING activation-induced IFNβ production also participated in the apoptosis mediated by VA-treated macrophage in SKBR3 and H1299 cells. Mouse models with 4 T1 tumors confirmed the anti-tumor properties of VA in vivo and revealed the infiltration of VA-induced cytotoxic T cells into the tumors. These data suggest that VA is an effective agonist of STING and provides a new perspective for cancer immunotherapy.
Pancreatic cancer (PC) is a highly devastating neoplasm due to its irrepressible characteristics and propensity to override the available treatment strategies. Rapid prevalence and enormous severity of this cancer urgently demand the exploration of novel approaches for the development of effective therapeutic measures. Metabolic derangement is one of the hallmarks of cancers which restructures mitochondrial activities and biological pathways. Apart from their bioenergetic and biosynthetic functions, mitochondria are also implicated in a myriad of cellular functions including proliferation, differentiation, apoptosis, senescence, homeostasis, and other cell regulatory mechanisms. It has been noted that PC, like other types of cancers, exploits these activities in favor of tumor growth and survival by inducing mitochondrial dysfunctions such as mitochondrial-DNA mutation, metabolic enzyme modification, ROS generation, mitophagy, evasion of apoptosis, and mitochondrial biogenesis. During pancreatic carcinogenesis, a large number of onco-factors including Bcl-2 family proteins, NF-κB, HIFs, NRF2, NOX, MFNs, DRP1, DUSP6, Cyp-D, PARKIN, and others are dysregulated, resulting into reprogramming of metabolic pathways and cellular kinetics. Hence, targeted interventions in these metabolic derangements may present some effective anticancer approaches. The current review gives an insight into various mitochondrial disorders and their targetable molecules in PC which may provide certain novel opportunities in the pursuit of therapeutic development. Furthermore, we have also discussed certain treatment perspectives in PC based on specific mitochondrial activities.
Background: A large number of breast cancer patients perishes due to metastasis instead of primary tumor, but molecular mechanisms contributing towards cancer metastasis remain poorly understood. Therefore, prompting development of novel treatment is inevitable. A vast variety of plant derived natural substance possesses several therapeutically active constituents, e.g. alkaloids, flavonoids, tannins, resins, terpenoids etc. that exhibit various pharmacological properties e.g. anti-inflammatory, anti-microbial and anti-cancer properties. Sanguinarine (SAN) alkaloid found its place among such naturally occurring substances that exerts several pharmacological activities, including anti-cancer effects. Purpose: Until now, role of SAN not only against epithelial-mesenchymal transition (EMT) but also against metastasis progression in breast cancer remains indistinct. Thus, aim of the present study was to investigate effects of SAN on EMT process and cancer metastasis in animal model. Methods: MTT assay was performed to assess SAN effects on proliferation in breast cancer. Scratch assay was performed to evaluate effects of SAN on migration in breast cancer. Colony formation assay was performed to determine effects of SAN on colonization characteristics of breast cancer. Western blotting was performed to measure EMT regulating protein expression as well as major pathway protein expression induced against TGF-beta treatment in breast cancer. Tail vein method of injecting breast cancer cells in bulb/c mice was conducted to study metastasis progression and thereafter assessing effects of SAN against metastasis in mice. Results: In vivo results: MTT assay performed, demonstrated dose dependent inhibition of cell proliferation in breast cancer. Scratch assay results showed, SAN played a major role as migration inhibitor in estrogen receptor positive (ER+) breast cancer. Colony forming assay results demonstrated that SAN constrains ability of breast cancer to develop into well-defined colonies. Western blotting results for EMT regulating protein expression, after TGF-beta treatment showed, SAN inhibited cadherin switch in ER+ breast cancer. Moreover, expression of pathway proteins involved in EMT process after TGF-beta treatment i.e. Smad, PI3K/Akt and MAP kinase were significantly masked against SAN treatment. In vivo results: The appearance of metastatic nodules in lung tissues of mice model, helps to study the effects of SAN against metastasis in bulb/c mice. The obtained results have confirmed that SAN impeded lung metastasis. The macroscopic examination has confirmed metastasis inhibitory role of SAN in breast cancer. The Hematoxylin and eosin (H&E) staining results further advocate anti-metastatic characteristics of SAN, presented by fewer metastatic nodule and lesions appearance in SAN treated mice compared to untreated metastasis mice. Conclusion: In summary, SAN displayed prominent anti-metastatic effects in animal model and anti-proliferation effects together with significant inhibitory potential on EMT regulating protein expression against TGF-beta treatment in ER+ breast cancer. So, overall findings of our study highlighted the pre-clinical significance of SAN in animal model therefore, further studies in humans as a part of clinical trial will be needed to establish pharmacokinetics and other effects of SAN, so that it can be a potential candidate for future treatment of metastatic breast cancer (MBC).
Female breast cancer has become the most commonly diagnosed cancer worldwide. As a tumor suppressor, estrogen receptor β (ERβ) can be potentially targeted for breast cancer therapy. TAD1822-7 was evaluated for ERβ-mediated autophagy and cell death using cell proliferation assay, Annexin V/PI staining, immunofluorescence, western blotting, ERβ siRNA, ERβ plasmid transfection and hypoxia cell models. TAD1822-7 upregulated ERβ causing cell death and induced mitochondrial dysfunction and autophagy companied with mitochondrial located ERβ. Enhanced levels of microtubule associated protein1 light chain 3 (LC3)-II and p62/SQSTM1 (p62) indicated that TAD1822-7 blocked the late-stage autolysosome formation, leading to cell death. Mechanistically, TAD1822-7-induced cell death was mediated by phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathways. Moreover, TAD1822-7 modulated hypoxia inducible factor (HIF) functions and autophagy via the inhibition of HIF-1β in the context of hypoxia-induced autophagy. ERβ overexpression and ERβ agonist showed similar effects, whereas ERβ siRNA abrogated TAD1822-7-induced cell death, the inhibition of PI3K/AKT pathway and autophagy. The involvement of PI3K/AKT pathway and autophagy was also demonstrated in TAD1822-7-treated hypoxic breast cancer cells. These findings provide new insight into the mechanism underlying the inhibitory effects of TAD1822-7 via ERβ-mediated pathways in breast cancer cells.
Lung cancer (LC) is one of the leading causes of cancer-related death. As one of the key features of tumor microenvironment, hypoxia conditions are associated with poor prognosis in LC patients. Upregulation of hypoxic-induced factor-1α (HIF-1α) leads to the activation of various factors that contribute to the increased drug resistance, proliferation, and migration of tumor cells. Apurinic/apyrimidinic endonuclease-1 (APEX1) is a multi-functional protein that regulates several transcription factors, including HIF-1α, that contribute to tumor growth, oxidative stress responses, and DNA damage. In this study, we explored the mechanisms underlying cell responses to hypoxia and modulation of APEX1, which regulate HIF-1α and downstream pathways. We found that hypoxia-induced APEX1/HIF-1α pathways regulate several key cellular functions, including reactive oxygen species (ROS) production, carbonic anhydrase 9 (CA9)-mediated intracellular pH, migration, and angiogenesis. Cephalomannine (CPM), a natural compound, exerted inhibitory effects in hypoxic LC cells via the inhibition of APEX1/HIF-1α interaction in vitro and in vivo. CPM can significantly inhibit cell viability, ROS production, intracellular pH, and migration in hypoxic LC cells as well as angiogenesis of HUVECs under hypoxia through the inhibition of APEX1/HIF-1α interaction. Taken together, CPM could be considered as a promising compound for LC treatment.
Pancreatic Cancer (PC) is a severe form of malignancy all over the world. Delayed diagnosis and chemoresistance are the major factors contributing to its poor prognosis and high mortality rate. The genetic and epigenetic regulations of biological pathways further complicate the progression and chemotherapy response to this cancer. MicroRNAs (MiRNAs) involvement has been observed in all types of cancers including PC. The understanding and categorization of miRNAs according to their specific targets are very important to develop early diagnostic and therapeutic interventions. The current review, emphasizing recent research findings, has categorized miRNAs that directly target the potential onco-factors that act as central converging signal-nodes in five major cancer-related pathways i.e., MAPK/ERK, JAK/STAT, Wnt/β-catenin, AKT/mTOR, and TGFβ in PC. The therapeutic perspectives of miRNAs in PC have also been discussed. This will help to understand the interplay of various miRNAs within foremost signaling pathways and develop a multifactorial approach to treat difficult-to-treat PC.
Background: Breast cancer is the most common female cancer worldwide. Large hypoxic area is one of the features of tumor microenvironment. Highly activated hypoxia-induced pathways positively correlate with poor clinical response to chemo- and radiotherapy and high mortality in breast cancer patients. Purpose: We explore the effect of sanguinarine on hypoxia-induced activation of Ephrin type-B receptor 4 (EphB4) and hypoxia inducible factor-1 alpha (HIF-1 alpha) pathways in breast cancer. Results: Hypoxia-induced expression of a receptor tyrosine kinase EphB4 was observed in hypoxic breast cancer cell models. Sanguinarine, a natural alkaloid, could effectively combat hypoxia-induced EphB4 and HIF-1 alpha expression. Sanguinarine inhibited the activation of downstream protein signal transducer and activator of transcription-3 (STAT3), thereby blocking hypoxia-induced HIF-1 alpha/STAT3 interaction and downregulating the mRNA levels of their target genes. Mechanically, sanguinarine attenuated HIF-1 alpha protein levels via inhibition of MAPK/ERK pathways and promotion of HIF-1 alpha proteasome degradation. Sanguinarine inhibited STAT3 activation through targeting its upstream EphB4 and accelerating STAT3 dephosphorylation. Correspondingly, xenograft models confirmed that sanguinarine treatment disrupted hypoxia-induced pathways and inhibited tumor growth in vivo. Conclusions: Our results may bring insights to the hypoxia-induced pathways in breast cancers, and suggest sanguinarine as a promising candidate for EphB4 and HIF-1 alpha-targeted inhibition.