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Chemotherapy, radiotherapy, and immunotherapy represent key tumour treatment strategies. Notably, immune checkpoint inhibitors (ICIs), particularly anti‐programmed cell death 1 (PD1) and anti‐programmed cell death ligand 1 (PD‐L1), have shown clinical efficacy in clinical tumour immunotherapy. However, the limited effectiveness of ICIs is evident due to many cancers exhibiting poor responses to this treatment. An emerging avenue involves triggering non‐apoptotic regulated cell death (RCD), a significant mechanism driving cancer cell death in diverse cancer treatments. Recent research demonstrates that combining RCD inducers with ICIs significantly enhances their antitumor efficacy across various cancer types. The use of anti‐PD‐1/PD‐L1 immunotherapy activates CD8+ T cells, prompting the initiation of novel RCD forms, such as ferroptosis, pyroptosis, and necroptosis. However, the functions and mechanisms of non‐apoptotic RCD in anti‐PD1/PD‐L1 therapy remain insufficiently explored. This review summarises the emerging roles of ferroptosis, pyroptosis, and necroptosis in anti‐PD1/PD‐L1 immunotherapy. It emphasises the synergy between nanomaterials and PD‐1/PD‐L1 inhibitors to induce non‐apoptotic RCD in different cancer types. Furthermore, targeting cell death signalling pathways in combination with anti‐PD1/PD‐L1 therapies holds promise as a prospective immunotherapy strategy for tumour treatment. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is the second leading cause of cancer‐related mortality in women, and targeting biological pathways such as the JNK pathway has proven to be a viable therapeutic target for BC therapy. Here, we synthesized piperazin‐2‐yl‐pyrimidines and evaluated them for anticancer activity against MCF‐7 cells. In addition, antioxidant, reactive oxygen species (ROS) inhibition, caspase activity, and toxicity in platelets were studied in the presence and absence of active compound IA‐6 or IA‐7. Our detailed experimental analysis found that the compound IA‐7 showed anticancer activity by either activating p‐JNK or by inducing radical species in cancer and thrombosis model. Evident to in vitro analysis, the structure based molecular interaction studies of binding of IA‐7 to JNK3S exhibited a significant binding energy of −7.56 kcal/mol which was found to be a better binder when compared to previously reported JNK inducer (PC‐12). Overall, we herein report the analytically pure IA‐7 as lead structure that could be used as a template to develop target based anticancer agents where JNK modulation is predominant. [ABSTRACT FROM AUTHOR]

Cancer cachexia is a multifactorial condition that contributes to the death of about 20% of cancer patients. It has the potential to cause weight loss, reduction in muscle mass, and loss of fat tissue, significantly lowering the quality of life. Currently, there are no approved drugs for cancer cachexia. Here, we have explored the possible impact of brassinin (BSN) on cancer cachexia under in vitro and in vivo settings. After differentiation, C2C12 and 3T3‐L1 cells were incubated with colorectal carcinoma cells conditioned media or BSN. For preclinical studies, mice were injected with HT‐29 cells followed by intraperitoneal administration of BSN, and muscle and adipose tissues were evaluated by Western blotting and hematoxylin and eosin staining. BSN effectively suppressed muscle atrophy by down‐regulating the levels of Muscle RING‐finger protein‐1 and Atrogin‐1, while also increasing the expression of myosin heavy chain in cachexia‐induced‐C2C12 myotubes. The induction of adipogenesis by BSN prevented adipocyte atrophy in cachexia‐induced 3T3‐L1 adipocytes. We also noted that BSN disrupted the interaction between COX‐2 and signaling transducer and activator of transcription 3 (STAT3) promoter, leading to down‐regulation of STAT3 activation. Moreover, it was found that BSN inhibited weight loss in mice and demonstrated anti‐cachexic effects. Overall, our observations indicate that BSN can attenuate cancer cachexia through diverse mechanisms. [ABSTRACT FROM AUTHOR]

A recent study published in MedComm explores the role of TMEM25 (transmembrane protein 25) in the regulation of EGFR-dependent STAT3 activation in triple-negative breast cancer (TNBC). The researchers found that TMEM25 physically associates with EGFR monomers, suppressing the phosphorylation of STAT3 and sequestering it in the cytoplasm. Lack of TMEM25 allows monomeric EGFR to activate STAT3 in a ligand-independent manner, promoting tumor progression. This study highlights the potential of targeting the monomeric EGFR/STAT3 signaling axis as a therapeutic strategy for TNBC. [Extracted from the article]

Signal transducer and activator of transcription 3 (STAT3) and STAT5 are the transcription factors that have been studied extensively in relevance to the development of cancers in humans. Suppression of either STAT3 or STAT5‐mediated signaling events has been demonstrated to be effective in inducing cytotoxicity in cancer cells. Herein, new hybrids of triazolyl‐indolo‐quinoxaline are synthesized and examined for their effect on the activation of STAT3 and STAT5 pathways in gastric cancer (GC) cells. Among the newly synthesized compounds, 2,3‐difluoro‐6‐((1‐(3‐fluorophenyl)‐1H‐1,2,3‐triazol‐5‐yl)methyl)‐6H‐indolo[2,3‐b]quinoxaline (DTI) displayed selective cytotoxicity against GC cells over their normal counterpart. Flow cytometric analysis, annexin‐V‐fluorescein isothiocyanate staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, live and dead assay, and caspase activation experiments suggested DTI as a potent inducer of apoptosis. The mechanistic approach revealed that DTI imparts cytotoxicity via downregulating the phosphorylation of STAT3Y705 and STAT5Y694/699. DTI significantly reduced the nuclear pool of STAT3/STAT5 and reduced the DNA interaction ability of STAT3/STAT5 as evidenced by immunofluorescence and electrophoretic mobility shift assay. Further investigation revealed that inhibitory effects towards STAT proteins were mediated through the suppression of upstream kinases such as JAK1, JAK2, and Src. Treatment of GC cells with pervanadate counteracted the DTI‐driven STAT3/STAT5 inhibition suggesting the involvement of tyrosine phosphatase. Upon DTI exposure, there was a significant upregulation in the mRNA and protein expression of PTPεC, which is a negative regulator of the JAK‐STAT pathway. Knockdown of PTPεC suppressed the DTI‐induced STATs inhibition in GC cells. Taken together, triazolyl‐indolo‐quinoxaline is presented as a new inhibitor of the STAT3/STAT5 pathway in GC cells. [ABSTRACT FROM AUTHOR]

Breast cancer is the most malignant tumor in women, and there is no absolute cure for it. Although treatment modalities including surgery, chemotherapy, and radiotherapy are utilized for breast cancer, it is still a life‐threatening disease for humans. Nanomedicine has provided a new opportunity in breast cancer treatment, which is the focus of the current study. The nanocarriers deliver chemotherapeutic agents and natural products, both of which increase cytotoxicity against breast tumor cells and prevent the development of drug resistance. The efficacy of gene therapy is boosted by nanoparticles and the delivery of CRISPR/Cas9, Noncoding RNAs, and RNAi, promoting their potential for gene expression regulation. The drug and gene codelivery by nanoparticles can exert a synergistic impact on breast tumors and enhance cellular uptake via endocytosis. Nanostructures are able to induce photothermal and photodynamic therapy for breast tumor ablation via cell death induction. The nanoparticles can provide tumor microenvironment remodeling and repolarization of macrophages for antitumor immunity. The stimuli‐responsive nanocarriers, including pH‐, redox‐, and light‐sensitive, can mediate targeted suppression of breast tumors. Besides, nanoparticles can provide a diagnosis of breast cancer and detect biomarkers. Various kinds of nanoparticles have been employed for breast cancer therapy, including carbon‐, lipid‐, polymeric‐ and metal‐based nanostructures, which are different in terms of biocompatibility and delivery efficiency. Highlights: Breast cancer is among the most malignant tumors around the world,Nanocarriers provide a platform for delivery of anticancer agents and their codelivery,Gene delivery and immunotherapy are boosted by nanostructures,Stimuli‐responsive nanocarriers selectively release cargo at tumor site,Nanoarchitectures can be employed for bioimaging in breast cancer. [ABSTRACT FROM AUTHOR]

A reliable and efficient in vitro model is needed to screen drugs for Alzheimer's disease (AD), as many drugs are currently in the developmental stage. To address this, we developed an in vitro model using amniotic membrane‐derived mesenchymal stem cells (AM‐MSCs) to screen novel drugs for AD. We differentiated AM‐MSCs into neurons and degenerated them using beta amyloid1‐42 (Aß). We then tested AD drugs, which are commercially available such as donepezil, rivastigmine, memantine, citicoline, and two novel drugs, that is, probucol, an anti‐hyperlipidaemic drug, and NMJ‐2, a cinnamic acid analogue for their potential to protect the cells against neurodegeneration. We used gene expression and immunofluorescence staining to assess the neuroprotective ability of these drugs. We also measured the ability of these drugs to reduce lactate dehydrogenase, reactive oxygen species, and nitric oxide levels, as well as their ability to stabilize the mitochondrial membrane potential and increase acetylcholine (ACh) levels. The AD drugs and novel drugs reduced cytotoxicity and oxidative stress, stabilized mitochondrial membrane potential, and restored ACh levels. Furthermore, they reduced BACE1 expression, with a concomitant increase in the expression of cholinergic markers. This AM‐MSCs‐based AD‐like model has immense potential to be an accurate human model and an alternative to animal models for testing a large number of lead compounds in a short time. Our results also suggest that the novel drugs probucol and NMJ‐2 may protect against Aß‐induced neurodegeneration. [ABSTRACT FROM AUTHOR]

Keap1‐Nrf2 is a fundamental signaling cascade known to promote or prevent carcinogenesis. Extensive studies identify the key target of modulatory aspects of Keap1‐Nrf2 signaling against cancer. Nutraceuticals are those dietary agents with many health benefits that have immense potential for cancer chemoprevention. The nutritional supplements known as nutraceuticals are found to be one of the most promising chemoprevention agents. Upon investigating the dual nature of Nrf2, it became clear that, in addition to shielding normal cells from numerous stresses, Nrf2 may also promote the growth of tumors. In the present review, we performed a systematic analysis of the role of 12 different nutraceuticals like curcumin, sulforaphane, resveratrol, polyunsaturated fatty acids (PUFA) from fish oil, lycopene, soybean, kaempferol, allicin, thymoquinone, quercetin, gingerol, and piperine in modulating the Nrf2/Keap1 signaling mechanism. Among these, 12 Generally Recognized As Safe (GRAS) certified nutraceuticals, sulforaphane is the most extensively studied compound in modulating Keap1‐Nrf signaling. Even though there is much evidence at preclinical levels, further high‐quality research is still required to validate the potential role of these nutraceuticals in Keap1‐Nrf2 modulation. [ABSTRACT FROM AUTHOR]

Gastrointestinal (GI) tumors (cancers of the esophagus, gastric, liver, pancreas, colon, and rectum) contribute to a large number of deaths worldwide. STAT3 is an oncogenic transcription factor that promotes the transcription of genes associated with proliferation, antiapoptosis, survival, and metastasis. STAT3 is overactivated in many human malignancies including GI tumors which accelerates tumor progression, metastasis, and drug resistance. Research in recent years demonstrated that noncoding RNAs (ncRNAs) play a major role in the regulation of many signaling pathways including the STAT3 pathway. The major types of endogenous ncRNAs that are being extensively studied in oncology are microRNAs, long noncoding RNAs, and circular RNAs. These ncRNAs can either be tumor‐promoters or tumor‐suppressors and each one of them imparts their activity via different mechanisms. The STAT3 pathway is also tightly modulated by ncRNAs. In this article, we have elaborated on the tumor‐promoting role of STAT3 signaling in GI tumors. Subsequently, we have comprehensively discussed the oncogenic as well as tumor suppressor functions and mechanism of action of ncRNAs that are known to modulate STAT3 signaling in GI cancers. [ABSTRACT FROM AUTHOR]

Epithelial‐mesenchymal transition (EMT) is a complex process with a primordial role in cellular transformation whereby an epithelial cell transforms and acquires a mesenchymal phenotype. This transformation plays a pivotal role in tumor progression and self‐renewal, and exacerbates resistance to apoptosis and chemotherapy. EMT can be initiated and promoted by deregulated oncogenic signaling pathways, hypoxia, and cells in the tumor microenvironment, resulting in a loss‐of‐epithelial cell polarity, cell–cell adhesion, and enhanced invasive/migratory properties. Numerous transcriptional regulators, such as Snail, Slug, Twist, and ZEB1/ZEB2 induce EMT through the downregulation of epithelial markers and gain‐of‐expression of the mesenchymal markers. Additionally, signaling cascades such as Wnt/β‐catenin, Notch, Sonic hedgehog, nuclear factor kappa B, receptor tyrosine kinases, PI3K/AKT/mTOR, Hippo, and transforming growth factor‐β pathways regulate EMT whereas they are often deregulated in cancers leading to aberrant EMT. Furthermore, noncoding RNAs, tumor‐derived exosomes, and epigenetic alterations are also involved in the modulation of EMT. Therefore, the regulation of EMT is a vital strategy to control the aggressive metastatic characteristics of tumor cells. Despite the vast amount of preclinical data on EMT in cancer progression, there is a lack of clinical translation at the therapeutic level. In this review, we have discussed thoroughly the role of the aforementioned transcription factors, noncoding RNAs (microRNAs, long noncoding RNA, circular RNA), signaling pathways, epigenetic modifications, and tumor‐derived exosomes in the regulation of EMT in cancers. We have also emphasized the contribution of EMT to drug resistance and possible therapeutic interventions using plant‐derived natural products, their semi‐synthetic derivatives, and nano‐formulations that are described as promising EMT blockers. [ABSTRACT FROM AUTHOR]

A novel kind of nonapoptotic, iron‐dependent cell death brought on by lipid peroxidation is known as ferroptosis. Numerous pathological processes, including neurotoxicity, neurological disorders, ischemia‐reperfusion damage, and particularly cancer, have been demonstrated to be influenced by changes in the ferroptosis‐regulating network. Recent studies have established the critical roles that ferroptosis can play in cancer development and the evolution of resistance to standard chemoradiotherapy, thus suggesting that ferroptosis may be a feasible therapeutic strategy for cancer management. Gene expression may be regulated at the transcriptional and posttranscriptional levels by long noncoding RNAs (lncRNAs). They have been implicated in tumorigenesis. Some lncRNAs participate in the biological process of ferroptosis, which represents an exciting alternative to regulate ferroptosis as a means of cancer therapy. Even though there is evidence that lncRNAs have a mechanistic role in the ferroptosis of cancer cells, research on the mechanism and potential treatments for these lncRNAs is still lacking. We elucidate the potential mechanisms by which lncRNAs modulate ferroptosis in cancer and examine the promise and challenges of employing lncRNAs as novel therapeutic targets in cancer. [ABSTRACT FROM AUTHOR]

Urological cancers are among the most common malignancies around the world. In particular, bladder cancer severely threatens human health due to its aggressive and heterogeneous nature. Various therapeutic modalities have been considered for the treatment of bladder cancer although its prognosis remains unfavorable. It is perceived that treatment of bladder cancer depends on an interdisciplinary approach combining biology and engineering. The nanotechnological approaches have been introduced in the treatment of various cancers, especially bladder cancer. The current review aims to emphasize and highlight possible applications of nanomedicine in eradication of bladder tumor. Nanoparticles can improve efficacy of drugs in bladder cancer therapy through elevating their bioavailability. The potential of genetic tools such as siRNA and miRNA in gene expression regulation can be boosted using nanostructures by facilitating their internalization and accumulation at tumor sites and cells. Nanoparticles can provide photodynamic and photothermal therapy for ROS overgeneration and hyperthermia, respectively, in the suppression of bladder cancer. Furthermore, remodeling of tumor microenvironment and infiltration of immune cells for the purpose of immunotherapy are achieved through cargo-loaded nanocarriers. Nanocarriers are mainly internalized in bladder tumor cells by endocytosis, and proper design of smart nanoparticles such as pH-, redox-, and light-responsive nanocarriers is of importance for targeted tumor therapy. Bladder cancer biomarkers can be detected using nanoparticles for timely diagnosis of patients. Based on their accumulation at the tumor site, they can be employed for tumor imaging. The clinical translation and challenges are also covered in current review. [ABSTRACT FROM AUTHOR]

Among all cancers, hepatocellular carcinoma (HCC) remains a lethal disease with limited treatment options. In this study, we have analyzed the possible inhibitory effects of Fangchinoline (FCN) on c‐Met, a protein known to regulate the rapid phosphorylation of downstream signals, as well as mediate aberrant growth, metastasis, survival, and motility in cancer. FCN inhibited the activation of c‐Met and its downstream signals PI3K, AKT, mTOR, MEK, and ERK under in vitro settings. Moreover, c‐Met gene silencing lead to suppression of PI3K/AKT/mTOR and MEK/ERK signaling pathways, and induced apoptotic cell death upon exposure to FCN. In addition, FCN markedly inhibited the expression of the various oncogenic proteins such as Bcl‐2/xl, survivin, IAP‐1/2, cyclin D1, and COX‐2. In vivo studies in HepG2 cells xenograft mouse model showed that FCN could significantly attenuate the tumor volume and weight, without affecting significant loss in the body weight. Similar to in vitro studies, expression level of c‐Met and PI3K/AKT/mTOR, MEK/ERK signals was also suppressed by FCN in the tissues obtained from mice. Therefore, the novel findings of this study suggest that FCN can potentially function as a potent anticancer agent against HCC. [ABSTRACT FROM AUTHOR]

Metastasis of tumor cells is a complex challenge and significantly diminishes the overall survival and prognosis of cancer patients. The epithelial‐to‐mesenchymal transition (EMT) is a well‐known mechanism responsible for the invasiveness of tumor cells. A number of molecular pathways can regulate the EMT mechanism in cancer cells and nuclear factor‐kappaB (NF‐κB) is one of them. The nuclear translocation of NF‐κB p65 can induce the transcription of several genes involved in EMT induction. The present review describes NF‐κB and EMT interaction in cancer cells and their association in cancer progression. Due to the oncogenic role NF‐κB signaling, its activation enhances metastasis of tumor cells via EMT induction. This has been confirmed in various cancers including brain, breast, lung and gastric cancers, among others. The ZEB1/2, transforming growth factor‐β, and Slug as inducers of EMT undergo upregulation by NF‐κB to promote metastasis of tumor cells. After EMT induction driven by NF‐κB, a significant decrease occurs in E‐cadherin levels, while N‐cadherin and vimentin levels undergo an increase. The noncoding RNAs can potentially also function as upstream mediators and modulate NF‐κB/EMT axis in cancers. Moreover, NF‐κB/EMT axis is involved in mediating drug resistance in tumor cells. Thus, suppressing NF‐κB/EMT axis can also promote the sensitivity of cancer cells to chemotherapeutic agents. [ABSTRACT FROM AUTHOR]

Curcumin is a phytochemical isolated from Curcuma longa with potent tumor‐suppressor activity, which has shown significant efficacy in pre‐clinical and clinical studies. Curcumin stimulates cell death, triggers cycle arrest, and suppresses oncogenic pathways, thereby suppressing cancer progression. Cisplatin (CP) stimulates DNA damage and apoptosis in cancer chemotherapy. However, CP has adverse effects on several organs of the body, and drug resistance is frequently observed. The purpose of the present review is to show the function of curcumin in decreasing CP's adverse impacts and improving its antitumor activity. Curcumin administration reduces ROS levels to prevent apoptosis in normal cells. Furthermore, curcumin can inhibit inflammation via down‐regulation of NF‐κB to maintain the normal function of organs. Curcumin and its nanoformulations can reduce the hepatoxicity, neurotoxicity, renal toxicity, ototoxicity, and cardiotoxicity caused by CP. Notably, curcumin potentiates CP cytotoxicity via mediating cell death and cycle arrest. Besides, curcumin suppresses the STAT3 and NF‐ĸB as tumor‐promoting pathways, to enhance CP sensitivity and prevent drug resistance. The targeted delivery of curcumin and CP to tumor cells can be mediated nanostructures. In addition, curcumin derivatives are also able to reduce CP‐mediated side effects, and increase CP cytotoxicity against various cancer types. [ABSTRACT FROM AUTHOR]

Several signaling pathways have been identified as important for developmental processes. One of such important cascades is the Wnt/β‐catenin signaling pathway, which can regulate various physiological processes such as embryonic development, tissue homeostasis, and tissue regeneration; while its dysregulation is implicated in several pathological conditions especially cancers. Interestingly, deregulation of the Wnt/β‐catenin pathway has been reported to be closely associated with initiation, progression, metastasis, maintenance of cancer stem cells, and drug resistance in human malignancies. Moreover, several genetic and experimental models support the inhibition of the Wnt/β‐catenin pathway to answer the key issues related to cancer development. The present review focuses on different regulators of Wnt pathway and how distinct mutations, deletion, and amplification in these regulators could possibly play an essential role in the development of several cancers such as colorectal, melanoma, breast, lung, and leukemia. Additionally, we also provide insights on diverse classes of inhibitors of the Wnt/β‐catenin pathway, which are currently in preclinical and clinical trial against different cancers. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs), a type of non‐coding RNA, are single‐stranded circularized molecules characterized by high abundance, evolutionary conservation and cell development‐ and tissue‐specific expression. A large body of studies has found that circRNAs exert a wide variety of functions in diverse biological processes, including cell cycle. The cell cycle is controlled by the coordinated activation and deactivation of cell cycle regulators. CircRNAs exert mutifunctional roles by regulating gene expression via various mechanisms. However, the functional relevance of circRNAs and cell cycle regulation largely remains to be elucidated. Herein, we briefly describe the biogenesis and mechanistic models of circRNAs and summarize their functions and mechanisms in the regulation of critical cell cycle modulators, including cyclins, cyclin‐dependent kinases and cyclin‐dependent kinase inhibitors. Moreover, we highlight the participation of circRNAs in cell cycle‐related signalling pathways and the clinical value of circRNAs as promising biomarkers or therapeutic targets in diseases related to cell cycle disorder. [ABSTRACT FROM AUTHOR]

In recent years, triple‐negative breast cancer (TNBC) has emerged as the most aggressive subtype of breast cancer and is usually associated with increased mortality worldwide. The severity of TNBC is primarily observed in younger women, with cases ranging from approximately 12%–24% of all breast cancer cases. The existing hormonal therapies offer limited clinical solutions in completely circumventing the TNBC, with chemoresistance and tumor recurrences being the common hurdles in the path of TNBC treatment. Accumulating evidence has correlated the dysregulation of long noncoding RNAs (lncRNAs) with increased cell proliferation, invasion, migration, tumor growth, chemoresistance, and decreased apoptosis in TNBC. Various clinical studies have revealed that aberrant expression of lncRNAs in TNBC tissues is associated with poor prognosis, lower overall survival, and disease‐free survival. Due to these specific characteristics, lncRNAs have emerged as novel diagnostic and prognostic biomarkers for TNBC treatment. However, the underlying mechanism through which lncRNAs perform their actions remains unclear, and extensive research is being carried out to reveal it. Therefore, understanding of mechanisms regulating the modulation of lncRNAs will be a substantial breakthrough in effective treatment therapies for TNBC. This review highlights the association of several lncRNAs in TNBC progression and treatment, along with their possible functions and mechanisms. [ABSTRACT FROM AUTHOR]

Hypercholesterolemia has been found to be closely linked with a significant increase in both cancer incidence and mortality. However, the exact correlation between serum cholesterol levels and cancer has not been completely deciphered. Here we analyzed the effect of low‐density lipoprotein (LDL) cholesterol on prostate and pancreatic cancer cells. We noted that LDL induced a substantial STAT3 activation and JAK1, JAK2, Src activation in diverse prostate and pancreatic tumor cells. Moreover, LDL promoted cancer cell proliferation, migration, and invasion as well as upregulated the expression of diverse oncogenic gene products. However, deletion of LDL‐activated STAT3 in LNCaP and PANC‐1 cells and reduced LDL‐induced cell viability. Simvastatin (SV) treatment also alleviated LDL‐induced cell viability and migration ability in both the prostate and pancreatic tumor cells. These results demonstrate that LDL‐induced STAT3 activation may exert a profound effect on the proliferation and survival of tumor cells. [ABSTRACT FROM AUTHOR]

Signal transducer and activator of transcription 3 (STAT3) is one of the crucial transcription factors, responsible for regulating cellular proliferation, cellular differentiation, migration, programmed cell death, inflammatory response, angiogenesis, and immune activation. In this review, we have discussed the classical regulation of STAT3 via diverse growth factors, cytokines, G‐protein‐coupled receptors, as well as toll‐like receptors. We have also highlighted the potential role of noncoding RNAs in regulating STAT3 signaling. However, the deregulation of STAT3 signaling has been found to be associated with the initiation and progression of both solid and hematological malignancies. Additionally, hyperactivation of STAT3 signaling can maintain the cancer stem cell phenotype by modulating the tumor microenvironment, cellular metabolism, and immune responses to favor drug resistance and metastasis. Finally, we have also discussed several plausible ways to target oncogenic STAT3 signaling using various small molecules derived from natural products. [ABSTRACT FROM AUTHOR]

Epidemiological evidence suggests that obesity can significantly increase the risk of various cancers, although the mechanisms underlying this link are completely unknown. Here, we analyzed the effect of adipocytes on melanoma and colon cancer cells proliferation, migration, and invasion. The potential effects of conditioned media (CM) obtained from differentiated mouse 3T3‐L1 cells and human adipose tissue‐derived mesenchymal stem cells (hAMSC) on the proliferation, migration, and invasion of B16BL6 melanoma and colon 26‐L5 cancer cells were investigated. The 3T3‐L1 and hAMSC CM increased cell proliferation, migration, and invasion in both the cell lines. In addition, adipocytes CM increased matrix metalloproteinase 9 (MMP‐9) and MMP‐2 activity in both B16BL6 and colon 26‐L5 cells. These effects were found to be associated with an increased expression of various oncogenic proteins in B16BL6 and colon 26‐L5 cells. Also, adipocyte CM induced Akt and mTOR activation in both tumor cell lines, and the pharmacological inhibition of Akt and mTOR blocked the CM induced Akt as well as mTOR activation and CM‐stimulated melanoma and colon cancer cell proliferation, migration, and invasion. These data suggest that adipocyte promotes melanoma and colon cancer progression through modulating the expression of diverse proteins associated with cancer growth and metastasis as well as modulation of the Akt/mTOR signaling. [ABSTRACT FROM AUTHOR]

Deguelin is a rotenoid compound that exists in abundant quantities in the bark, roots, and leaves of the Leguminosae family of plants. An analysis of evidence from both in vitro and in vivo studies suggests that deguelin displays potent anticancer activity against multiple cancer types and exhibits chemopreventive potential in Akt‐inducible transgenic mouse models. Deguelin appears to impede carcinogenesis by enhancing cell apoptosis and hindering malignant transformation and tumor cell propagation. Crucial oncogenic pathways likely targeted by deguelin include the epithelial‐to‐mesenchymal transition; angiogenesis‐related pathways; and the phosphoinositide 3‐kinase/Akt, Wnt, epidermal growth factor receptor, c‐Met, and hedgehog signal transduction cascades. This review article provides a comprehensive summary of current preclinical research featuring deguelin as a leading chemotherapeutic and chemopreventive compound, and it highlights the importance of identifying companion molecular biomarkers and performing systemic pharmacokinetic studies for accelerating the process of developing deguelin as a clinical anticancer agent. Deguelin can modulate various key hallmarks of cancer initiation, promotion, and progression, as well as alter the activation/expression of various oncogenic molecules in tumor cells. It is also shown to exhibit significant chemopreventive and therapeutic effects in different cancer mouse models. [ABSTRACT FROM AUTHOR]

Autophagy, also known as macroautophagy, is a tightly regulated process involved in the stress responses, such as starvation. It is a vacuolar, lysosomal pathway for the degradation of damaged proteins and organelles in eukaryotic cells. Autophagy also plays a key role in various tissue processes and immune responses and in the regulation of inflammation. Over the past decade, three levels of autophagy regulation have been identified in mammalian cells: 1) signaling, 2) autophagosome formation, and 3) autophagosome maturation and lysosomal degradation. Any deregulation of the autophagy processes can lead to the development of diverse chronic diseases, such as diabetes, obesity, cardiovascular disease, neurodegenerative disease, and malignancies. However, the potential role of autophagy in cancer is rather complex and has been associated with both the induction and the inhibition of neoplasia. Several synthetic autophagy modulators have been identified as promising candidates for cancer therapy. In addition, diverse phytochemicals derived from natural sources, such as curcumin, ursolic acid, resveratrol, thymoquinone, and γ-tocotrienol, also have attracted attention as promising autophagy modulators with minimal side effects. In this review, the authors discuss the importance of autophagy regulators and various natural compounds that induce and/or inhibit autophagy in the prevention and therapy of cancer. [ABSTRACT FROM AUTHOR]

Recent discoveries in the non-coding genome have challenged the original central dogma of molecular biology, as non-coding RNAs and related processes have been found to be important in regulating gene expression. MicroRNAs and long non-coding RNAs (lncRNAs) are among those that have gained attention recently in human diseases, including cancer, with the involvement of many more non-coding RNAs (ncRNAs) waiting to be discovered. ncRNAs are a group of ribonucleic acids transcribed from regions of the human genome, which do not become translated into proteins, despite having essential roles in cellular physiology. Deregulation of ncRNA expression and function has been observed in cancer pathogenesis. Recently, the roles of a group of ncRNA known as lncRNA have gained attention in cancer, with increasing reports of their oncogenic involvement. Female reproductive cancers remain a leading cause of death in the female population, accounting for almost a third of all female cancer deaths in 2016. The Wnt signalling pathway is one of the most important oncogenic signalling pathways which is hyperactivated in cancers, including female reproductive cancers. The extension of ncRNA research into their mechanistic roles in human cancers has also led to novel reported roles of ncRNAs in the Wnt pathway and Wnt-mediated oncogenesis. This review aims to provide a critical summary of the respective roles and cellular functions of Wnt-associated lncRNAs in female reproductive cancers and explores the potential of circulating cell-free lncRNAs as diagnostic markers and lncRNAs as therapeutic targets.Linked Articles: This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc. [ABSTRACT FROM AUTHOR]

Wildlife trade presents a major threat to primate populations, which are in demand from local to international scales for a variety of uses from food and traditional medicine to the exotic pet trade. We argue that an interdisciplinary framework to facilitate integration of socioeconomic, anthropological, and biological data across multiple spatial and temporal scales is essential to guide the study of wildlife trade dynamics and its impacts on primate populations. Here, we present a new way to design research on wildlife trade in primates using a systems thinking framework. We discuss how we constructed our framework, which follows a social-ecological system framework, to design an ongoing study of local, regional, and international slow loris ( Nycticebus spp.) trade in Vietnam. We outline the process of iterative variable exploration and selection via this framework to inform study design. Our framework, guided by systems thinking, enables recognition of complexity in study design, from which the results can inform more holistic, site-appropriate, and effective trade management practices. We place our framework in the context of other approaches to studying wildlife trade and discuss options to address foreseeable challenges to implementing this new framework. [ABSTRACT FROM AUTHOR]

Epithelial-to-mesenchymal transition (EMT) is a critical cellular phenomenon regulating tumor metastases. In the present study, we investigated whether ginkgolic acid can affect EMT in lung cancer cells and the related underlying mechanism(s) of its actions. We found that ginkgolic acid C15:1 (GA C15:1) inhibited cell proliferation, invasion, and migration in both A549 and H1299 lung cancer cells. GA C15:1 also suppressed the expression of EMT related genes (Fibronectin, Vimentin, N-cadherin, MMP-9, MMP-2, Twist and Snail) and suppressed TGF-β-induced EMT as assessed by reduced expression of mesenchymal markers (Fibronectin, Vimentin, N-cadherin), MMP-9, MMP-2, Twist and Snail. However, GA C15:1 did not affect the expression of various epithelial marker proteins (Occludin and E-cadherin) in both A549 and H1299 cells. TGF-β-induced morphologic changes from epithelial to mesenchymal cells and induction of invasion and migration were reversed by GA C15:1. Finally, GA C15:1 not only abrogated basal PI3K/Akt/mTOR signaling cascade, but also reduced TGF-β-induced phosphorylation of PI3K/Akt/mTOR pathway in lung cancer cells. Overall, these findings suggest that GA C15:1 suppresses lung cancer invasion and migration through the inhibition of PI3K/Akt/mTOR signaling pathway and provide a source of potential therapeutic compounds to control the metastatic dissemination of tumor cells. [ABSTRACT FROM AUTHOR]

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have become a rising threat to public health. There is an urgent need for development of promising new therapeutic agents against drug resistant bacteria like S. aureus . This report discusses purification and characterization of proteins from Indian Russell’s viper snake venom. Novel 15-kDa proteins called “Viperatoxin” (VipTx-I and VipTx-II) were extracted from the whole venom and evaluated using in vitro antimicrobial experiments. The N-terminal amino acid sequence of “Viperatoxin” showed high sequence homology to daboiatoxin isolated from the same venom and also matched phospholipase A 2 (PLA 2 ) enzymes isolated from other snake venoms. In an in vitro plate assay, VipTx-II but not VipTx-I showed strong antimicrobial effects against S. aureus and Burkholderia pseudomallei (KHW & TES), Proteus vulgaris and P. mirabilis . The VipTx-II was further tested by a broth-dilution assay at 100–3.125 μg/ml concentrations. The most potent bactericidal effect was found at the lowest dilutions (MICs of 6.25 μg/ml) against B. pseudomallei , S. aureus and P. vulgaris (MICs of 12.25 μg/ml). Electron microscopic investigation revealed that the protein-induced bactericidal potency was closely associated with pore formation and membrane damage, even at the lowest concentrations (<20 μg/ml). The toxin caused a low level of cytotoxic effects as observed in human (THP-1) cells at higher concentrations. Molecular weight determinations of VipTx-II by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed one major, along with a few minor bands. The results indicate that VipTx-II plays a significant role in bactericidal and membrane damaging effects in vitro . Non-cytotoxic properties on human cells highlight it as a promising candidate for further evaluation of antimicrobial potential in vivo . [ABSTRACT FROM AUTHOR]

Background and Purpose Aberrant activation of STAT3 is frequently encountered and promotes proliferation, survival, metastasis and angiogenesis in hepatocellular carcinoma ( HCC). Here, we have investigated whether emodin mediates its effect through interference with the STAT3 activation pathway in HCC. Experimental Approach The effect of emodin on STAT3 activation, associated protein kinases and apoptosis was investigated using various HCC cell lines. Additionally, we also used a predictive tumour technology to analyse the effects of emodin . The in vivo effects of emodin were assessed in an orthotopic mouse model of HCC. Key Results Emodin suppressed STAT3 activation in a dose- and time-dependent manner in HCC cells, mediated by the modulation of activation of upstream kinases c- Src, JAK1 and JAK2. Vanadate treatment reversed emodin-induced down-regulation of STAT3, suggesting the involvement of a tyrosine phosphatase and emodin induced the expression of the tyrosine phosphatase SHP-1 that correlated with the down-regulation of constitutive STAT3 activation. Interestingly, silencing of the SHP-1 gene by siRNA abolished the ability of emodin to inhibit STAT3 activation. Finally, when administered i.p., emodin inhibited the growth of human HCC orthotopic tumours in male athymic nu/nu mice and STAT3 activation in tumour tissues. Conclusions and Implications Emodin mediated its effects predominantly through inhibition of the STAT3 signalling cascade and thus has a particular potential for the treatment of cancers expressing constitutively activated STAT3. [ABSTRACT FROM AUTHOR]

The activation of signal transducers and activators of transcription 3 (STAT3) has been closely linked with the proliferation, survival, invasion, and angiogenesis of hepatocellular carcinoma (HCC) and represents an attractive target for therapy. In the present report, we investigated whether honokiol mediates its effect through interference with the STAT3 activation pathway. The effect of honokiol on STAT3 activation, associated protein kinases, and phosphatase, STAT3-regulated gene products and apoptosis was investigated using both functional proteomics tumor pathway technology platform and different HCC cell lines. We found that honokiol inhibited both constitutive and inducible STAT3 activation in a dose- and time-dependent manner in HCC cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src, Janus-activated kinase 1, and Janus-activated kinase 2. Vanadate treatment reversed honokiol-induced down-regulation of STAT3, suggesting the involvement of a tyrosine phosphatase. Indeed, we found that honokiol induced the expression of tyrosine phosphatase SHP-1 that correlated with the down-regulation of constitutive STAT3 activation. Moreover, deletion of SHP-1 gene by siRNA abolished the ability of honokiol to inhibit STAT3 activation. The inhibition of STAT3 activation by honokiol led to the suppression of various gene products involved in proliferation, survival, and angiogenesis. Finally, honokiol inhibited proliferation and significantly potentiated the apoptotic effects of paclitaxel and doxorubicin in HCC cells. Overall, the results suggest that honokiol is a novel blocker of STAT3 activation and may have a great potential for the treatment of HCC and other cancers. J. Cell. Physiol. 227: 2184-2195, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background and Purpose: Activation of pro-inflammatory transcription factors NF-κB and signal transducer and activator of transcription 3 (STAT3) is one of the major contributors to both pathogenesis and chemoresistance in multiple myeloma (MM), which results in high mortality rate. Thus, in the present study, we investigated whether celastrol could suppress the proliferation and induce chemosensitization of MM cells by interfering with NF-κB and STAT3 activation pathways.Experimental Approach: The effects of celastrol were investigated using both a virtual predictive tumour cell system and different MM cell lines resistant to doxorubicin, melphalan and bortezomib.Key Results: Celastrol inhibited the proliferation of MM cell lines regardless of whether they were sensitive or resistant to bortezomib and other conventional chemotherapeutic drugs. It also synergistically enhanced the apoptotic effects of thalidomide and bortezomib. This correlated with the down-regulation of various proliferative and anti-apoptotic gene products including cyclin D1, Bcl-2, Bcl-xL, survivin, XIAP and Mcl-1. These effects of celastrol were mediated through suppression of constitutively active NF-κB induced by inhibition of IκBα kinase activation; and the phosphorylation of IκBα and of p65. Celastrol also inhibited both the constitutive and IL6-induced activation of STAT3, which induced apoptosis as indicated by an increase in the accumulation of cells in the sub-G1 phase, an increase in the expression of pro-apoptotic proteins and activation of caspase-3.Conclusions and Implications: Thus, based on our experimental findings, we conclude that celastrol may have great potential as a treatment for MM and other haematological malignancies. [ABSTRACT FROM AUTHOR]

Increasing evidences indicate that CXCR4/CXCL12 signaling pathway plays a pivotal role in the process of distant site metastasis that accounts for more than 90% of prostate cancer related deaths in patients. Thus, novel drugs that can downregulate CXCR4/CXCL12 axis have a great potential in the treatment of metastatic prostate cancer. In this report, we tested an agent, ursolic acid (UA) for its ability to modulate CXCR4 expression in prostate cancer cell lines and inhibit metastasis in vivo in transgenic adenocarcinoma of mouse prostate (TRAMP) model. We observed that UA downregulated the expression of CXCR4 in prostate cancer cells irrespective of their HER2 status in a dose- and time-dependent manner. Neither proteasome inhibitor nor lysosomal stabilization had any effect on UA-induced decrease in CXCR4 expression. When investigated for the molecular mechanisms, it was observed that the downregulation of CXCR4 was due to transcriptional regulation as indicated by downregulation of mRNA expression, inhibition of NF-κB activation and modulation of chromatin immunoprecipitation activity. Suppression of CXCR4 expression by UA further correlated with the inhibition of CXCL12-induced migration and invasion in prostate cancer cells. Finally, we also found that UA treatment can inhibit metastasis of prostate cancer to distal organs, including lung and liver and suppress CXCR4 expression levels in the prostate tissues of TRAMP mice. Overall, our experimental findings suggest that UA exerts its antimetastatic effects through the suppression of CXCR4 expression in prostate cancer both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Background and Purpose: Activation of signal transducer and activator of transcription 3 (STAT3) play a critical role in the survival, proliferation, angiogenesis and chemoresistance of tumour cells. Thus, agents that suppress STAT3 phosphorylation have potential as cancer therapies. In the present study, we investigated whether the apoptotic, antiproliferative and chemosensitizing effects of γ-tocotrienol are associated with its ability to suppress STAT3 activation in hepatocellular carcinoma (HCC).Experimental Approach: The effect of γ-tocotrienol on STAT3 activation, associated protein kinases and phosphatase, STAT3-regulated gene products, cellular proliferation and apoptosis in HCC cells was investigated.Key Results: γ-Tocotrienol inhibited both the constitutive and inducible activation of STAT3 with minimum effect on STAT5. γ-Tocotrienol also inhibited the activation of Src, JAK1 and JAK2 implicated in STAT3 activation. Pervanadate reversed the γ-tocotrienol-induced down-regulation of STAT3, suggesting the involvement of a protein tyrosine phosphatase. Indeed, we found that γ-tocotrienol induced the expression of the tyrosine phosphatase SHP-1 and deletion of the SHP-1 gene by small interfering RNA abolished the ability of γ-tocotrienol to inhibit STAT3 activation. γ-Tocotrienol also down-regulated the expression of STAT3-regulated gene products, including cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1 and vascular endothelial growth factor. Finally, γ-tocotrienol inhibited proliferation, induced apoptosis and significantly potentiated the apoptotic effects of chemotherapeutic drugs (paclitaxel and doxorubicin) used for the treatment of HCC.Conclusions and Implications: Overall, these results suggest that γ-tocotrienol is a novel blocker of the STAT3 activation pathway, with a potential role in future therapies for HCC and other cancers. [ABSTRACT FROM AUTHOR]

Background and Purpose: Constitutive activation of the signal transducer and activator of transcription 3 (STAT3) pathway is frequently encountered in several human cancers including multiple myeloma (MM). Thus, agents that suppress STAT3 phosphorylation have a potential for treatment of MM. In the present report, we investigated whether thymoquinone (TQ), the main component isolated from the medicinal plant Nigella sativa, modulated the STAT3 signalling pathway in MM cells.Experimental Approach: The effect of TQ on both constitutive and IL-6-induced STAT3 activation, associated protein kinases, STAT3-regulated gene products involved in proliferation, survival and angiogenesis, cellular proliferation and apoptosis in MM cells, was investigated.Key Results: We found that TQ inhibited both constitutive and IL-6-inducible STAT3 phosphorylation which correlated with the inhibition of c-Src and JAK2 activation. Vanadate reversed the TQ-induced down-regulation of STAT3 activation, suggesting the involvement of a protein tyrosine phosphatase. Indeed, we found that TQ can induce the expression of Src homology-2 phosphatase 2 that correlated with suppression of STAT3 activation. TQ also down-regulated the expression of STAT3-regulated gene products, such as cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1 and vascular endothelial growth factor. Finally, TQ induced the accumulation of cells in sub-G1 phase, inhibited proliferation and induced apoptosis, as indicated by poly ADP ribose polymerase cleavage. TQ also significantly potentiated the apoptotic effects of thalidomide and bortezomib in MM cells.Conclusions and Implications: Our study has identified STAT3 signalling as a target of TQ and has thus raised its potential application in the prevention and treatment of MM and other cancers. [ABSTRACT FROM AUTHOR]

Simvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, is a cholesterol-lowering drug that may play a role in bone metabolism through a mechanism that is not fully understood. Recently, receptor activator of NF-κB ligand (RANKL), a member of the TNF superfamily, has emerged as a major mediator of bone loss via activation of osteoclastogenesis. The latter is also associated with certain cancers such as multiple myeloma and breast cancer. Whether simvastatin can modulate RANKL-induced or cancer induced osteoclastogenesis was investigated. The effect of simvastatin on RANKL signaling and consequent osteoclastogenesis was investigated. RANKL induced NF-κB activation, whereas pretreatment with simvastatin completely suppressed such activation and correlated with suppression of RANKL-induced activation of IκBα kinase, IκBα phosphorylation and IκBα degradation. Similarly, RANKL induced the differentiation of monocytic cells to osteoclasts, whereas simvastatin suppressed it. The inhibition was maximal when cells were exposed to both simvastatin and RANKL simultaneously and minimal when simvastatin was added 1 day after RANKL treatment. Simvastatin also inhibited the osteoclastogenesis induced by human breast cancer and by multiple myeloma cells. Together, our results indicate that simvastatin inhibits the RANKL-induced NF-κB activation pathway that leads to suppression of osteoclastogenesis induced by RANKL and by tumor cells, thereby suggesting its therapeutic potential in osteoporosis and in cancer-related bone loss. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Nuclear Factor-κB (NF-κB) activation and COX-2 overexpression have been reported in head and neck cancer, but the relationship between these proteins remains to be investigated. To determine the relationship between NF-κB and COX-2 in Smokeless Tobacco (ST) associated oral tumorigenesis, we performed immunohistochemistry in serial sections from 107 OSCCs, 78 oral precancerous lesions (OPLs) (58 hyperplasias, 20 dysplasias) and 15 histologically normal oral tissues and correlated with clinicopathological data. Significant increase in NF-κB and COX-2 immunopositivity was observed from normal oral mucosa to OPLs to OSCCs ( p = 0.009 and p = 0.002 respectively). Upregulation of NF-κB and COX-2 was observed as early as in hyperplasia [ p = 0.006; OR = 6.1 and p = 0.003; OR = 7.6, respectively]. Expression of both proteins was found to be significantly associated in OPLs ( p = 0.000; OR = 12.6) and OSCCs ( p = 0.001; OR = 4.0). Intriguingly, khaini consumption correlated with NF-κB immunopositivity in OPLs ( p = 0.05, OR = 3.8) and OSCCs ( p = 0.01, OR = 3.4) and with COX-2 expression in OPLs ( p = 0.03; OR = 4.3). In vitro experimental system of ST associated oral carcinogenesis was used to demonstrate ST (khaini) and NNK mediated activation of NF-κB and COX-2, supporting the clinical data. In conclusion, this study demonstrates correlation between over expression of NF-κB and COX-2 in early precancerous stages of development of oral cancer and sustained elevation down the tumorigenic pathway, underscoring their potential as targets for early intervention. In vitro studies demonstrated that NNK may be one of the carcinogenic components of ST (khaini) inducing activation of NF-κB and COX-2 in oral precancer and cancer cells, suggesting plausible role in ST-induced oral carcinogenesis. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]