Search Results (1,341)

Background/Objectives: Malignant melanoma is characterized by constitutive PI3K/Akt/mTOR and MAPK activation, driving aggressive behavior and therapeutic resistance. Alpha-lipoic acid (αLA), a naturally occurring dithiol compound with an established clinical safety profile, has shown anticancer potential; however, its integrated molecular mechanisms in melanoma remain poorly defined. This study aimed to comprehensively evaluate the cytotoxic and mechanistic effects of αLA in B16F10 murine melanoma cells. Methods: Antiproliferative effects were assessed by MTT assay at four concentrations (250, 500, 750, 1000 µM) over 48 h. Protein levels of apoptotic markers (Bax, Bcl-2, Caspase-3, AIF), kinase signaling components (p-Akt, p-mTOR, p-ERK, p-JNK), ER stress markers (GRP78, GADD153/CHOP), and cell cycle regulator Wee1 were quantified by ELISA at a specifically selected sub-lethal concentration of 750 µM (inducing ~38% growth inhibition). Results: αLA dose-dependently inhibited B16F10 proliferation. At 750 µM, it triggered robust intrinsic apoptotic signaling, evidenced by a nearly 10-fold shift in the Bax/Bcl-2 ratio and greater than 9-fold Caspase-3 activation. Elevated AIF suggested profound mitochondrial stress and the potential priming of concurrent caspase-independent cell death mechanisms. αLA suppressed survival signaling by reducing p-Akt (44%), p-mTOR, p-ERK, and p-JNK. Treatment triggered lethal ER stress via GRP78 and GADD153/CHOP upregulation and upregulated Wee1, suggesting the induction of stress-responsive checkpoint signaling. The simultaneous CHOP upregulation and p-Akt suppression highlight a concurrent dysregulation of stress and survival pathways, suggesting a potential pro-apoptotic interplay. Conclusions: αLA exerts potent multi-target anticancer effects by inducing a broad spectrum of associated molecular changes, including the suppression of PI3K/Akt/mTOR and MAPK networks, induction of ER stress, engagement of cell cycle checkpoints, and activation of the mitochondrial Bax/Bcl-2/Caspase-3 axis. Importantly, these correlative findings do not establish proven pathway dependencies. Nevertheless, this concurrent dysregulation positions αLA as a potential disruptor of inter-pathway resilience underlying drug resistance. Full article

Cetuximab and panitumumab are anti-EGFR monoclonal antibodies widely used for the treatment of colorectal cancers. However, due to various mechanisms of resistance to these targeted therapies, the patients’ responses vary. These resistances remain a major obstacle in treatment and overcoming them has become a key emphasis of current therapeutic strategies. Intrinsic and acquired resistance often lead to reactivation of downstream signaling pathways, mainly the RAS-RAF-MEK-ERK (MAPK pathway) and PI3K-AKT axes. Prior existing mutations in KRAS, NRAS, and BRAF result in primary resistance by constantly activating the signals, irrespective of EGFR inhibition. That said, acquired resistance manifests under therapeutic burden through the process of clonal evolution via KRAS and BRAF alterations, restoring MAPK pathway activity despite EGFR inhibition. In addition to those mutations, tumor cells exploit mechanisms independent of EGFR, such as the pathway bypass, which includes amplification of ERBB family receptors like HER2 (ERBB2) and activation of MET signaling. To overcome these resistances, novel strategies have emerged, which target multiple nodes within the oncogenic networks. Such methods include vertical pathway inhibition, multi-kinase inhibition, liquid-biopsy-guided therapy, and anti-EGFR rechallenge. Reactivation driven by secondary mutation can be prevented by targeting multiple nodes within the MAPK cascade simultaneously, which is referred to as the vertical pathway inhibition. Overall, this review underscores that overcoming therapeutic resistance requires a multidimensional approach that integrates molecular profiling, rational combination therapies, and adaptive treatment. Finally, these advances underscore the shift toward precision oncology, where therapy is tailored to tumor evolution, leading to improved response and patient outcome. Full article

Retroviruses induce immunosuppression in their infected hosts. This phenomenon is well described for the immunodeficiency viruses, with human immunodeficiency virus type 1 (HIV-1) representing the best-studied example, but it also occurs in other retroviral infections. Immunosuppressive properties were first characterized in murine leukemia viruses (MuLV). Additional well-studied examples include feline leukemia virus (FeLV) and koala retrovirus (KoRV). Investigations into the mechanisms underlying retrovirus-induced immunosuppression revealed that not only inactivated viral particles but also their purified transmembrane (TM) envelope proteins exhibit immunosuppressive activity. However, in certain retroviral infections, additional viral proteins contribute to the immunosuppression in vivo. Within the TM envelope proteins, a highly conserved region—designated the immunosuppressive (isu) domain—was identified. Synthetic peptides corresponding to this domain suppress a wide range of in vitro immune responses, possibly by regulating Ras-Raf-MEK-MAPK and PI3K-AKT-mTOR pathways. They modulate cytokine release and alter gene expression in immune cells, mirroring the activity of the corresponding TM envelope protein. Mutations in the sequence abrogate the effect. Numerous TM envelope proteins have demonstrated immunosuppressive activity in vivo in a tumor rejection model, and mutations within the isu domain also abrogate this function. These studies have important implications for reproduction, particularly through the immunosuppressive syncytins in the placenta, for tumor development, where similar mechanisms may protect cancer cells from the host immune system, and for vaccine development and xenotransplantation. Notably, immunization with TM envelope proteins carrying mutations in the isu domain elicits stronger immune responses compared with the wild-type proteins. Finally, the potential of retroviral TM envelope proteins to protect xenotransplants from immune rejection will be discussed. Full article

Collagen peptides have been widely studied for their beneficial effects on skin health; however, their potential role in hair growth remains insufficiently explored. This study aimed to investigate the effects of orally administered low-molecular-weight fish collagen peptide (SH-GT) on hair regrowth and its underlying mechanisms in a hair-removed C57BL/6J mouse model. Mice were administered SH-GT (100, 300, or 600 mg/kg body weight) or a positive control (Pansidil, 400 mg/kg) daily for 28 days. SH-GT significantly enhanced hair regrowth, as evidenced by the increased hair growth area. Histological analysis revealed increased dermal thickness and visible hair follicle structures in SH-GT-treated groups. At the molecular level, SH-GT upregulated proliferation-related proteins, including PCNA and Cyclin D1, and activated Wnt/β-catenin signaling. In addition, SH-GT enhanced PI3K/Akt/mTOR signaling, suggesting improved cellular growth and survival. Conversely, SH-GT suppressed hair growth inhibitory pathways by reducing BMP4 expression and decreasing Smad phosphorylation. Furthermore, SH-GT increased the mRNA expression of growth factors such as IGF-1, HGF, VEGF, EGF, and FGF7. In conclusion, SH-GT promotes hair regrowth by simultaneously activating proliferation-related signaling pathways and suppressing inhibitory mechanisms, thereby improving the dorsal skin microenvironment associated with hair regrowth. These findings suggest that SH-GT may serve as a promising functional ingredient for improving hair growth. Full article

Efficient milk protein synthesis in dairy cows, particularly casein production, is crucial for milk quality but has low nitrogen conversion efficiency. This study aimed to determine whether an optimal ratio of glycine, asparagine, and phenylalanine could synergistically promote α-casein synthesis in bovine mammary epithelial cells (MAC-T) and to elucidate its mechanism via the PI3K-AKT-mTOR signaling pathway. Single-factor experiments and response surface central composite design were conducted to determine the optimal amino acid combination. α-Casein synthesis was measured by ELISA, gene expression by RT-qPCR, and protein phosphorylation by Western blot. A PI3K-specific inhibitor (LY294002) was used in a blocking experiment to validate the involvement of the PI3K-AKT-mTOR pathway. Results: The optimal ratio was 9.898 mmol/L glycine, 7.014 mmol/L asparagine, and 5.865 mmol/L phenylalanine (molar ratio 1.69:1.20:1.00). This combination significantly increased α-casein synthesis and secretion compared to any single amino acid (p < 0.01), demonstrating a synergistic effect. It also upregulated CSN1S1 and CSN1S2 expression and activated the PI3K-AKT-mTOR pathway at both transcriptional and translational levels. The addition of LY294002 completely abolished these effects, confirming the pathway’s crucial role. The optimal combination of glycine, asparagine, and phenylalanine synergistically enhances α-casein synthesis in MAC-T cells by activating the PI3K-AKT-mTOR pathway. These findings provide a theoretical basis for developing targeted amino acid supplementation strategies to improve milk protein production in dairy cows. Full article

Ovarian cancer (OVC) is a leading cause of gynecological cancer mortality due to late-stage diagnosis and chemoresistance. Among the multiple molecular mediators, oncogenic epidermal growth factor receptor (EGFR) signaling has emerged as a key regulator of tumor progression and drug resistance, ultimately governing cancer survival. Therefore, this review focused on the molecular mechanisms of aberrant EGFR signaling to promote chemoresistance in ovarian cancer through multiple interlinking pathways, including the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of the rapamycin (mTOR), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling cascades. These pathways act in concert to confer resistance, including proliferation, antiapoptotic effects, cancer stem cell maintenance, and facilitating epithelial-mesenchymal transition (EMT), which function together to decrease sensitivity towards platinum-based and taxane chemotherapies. Furthermore, we incorporate novel evidence regarding EGFR cross-talk with extracellular matrix (ECM) and metabolic reprogramming, especially their relevance to immune evasion mechanisms, hypoxia, and extracellular vesicles (EVs)-mediated signaling. In addition, we elaborated on the limitation of the current EGFR targeting therapy, which will be beneficial for further designing new combinatorial treatment approaches by using EGFR inhibitors with immunotherapy, nanocarriers, and microbiota modulators. Overall, this review highlights the updated role of EGFR signaling as a key regulator of chemoresistance in ovarian cancer, providing insights for developing targeted therapies to overcome drug resistance and improve patient survival. Full article

Muscle wasting associated with gastric cancer represents a complex, multifactorial systems disorder involving inflammatory, anabolic, mechanosensory, calcium-regulatory, mitochondrial, and proteostatic disruption. This review synthesizes current evidence regarding the cellular and physiological mechanisms involved in skeletal muscle dysfunction in gastric cancer and provides a unifying framework centered on loss of signaling coherence. Specifically, it examines IL-6/STAT3 and NF-κB inflammatory signaling, the myostatin–activin–ACVR2B–SMAD pathway, PI3K/Akt/mTOR signaling, mechanotransduction, excitation–metabolism coupling, calcium homeostasis, mitochondrial function, and proteostasis. Although individual components of these pathways have been implicated in muscle wasting associated with chronic disease, current evidence suggests that they interact through positive feedback loops. Inflammation, anabolic resistance, impaired force-to-signal conversion, mitochondrial stress, altered intracellular calcium homeostasis, and disrupted protein quality control may reinforce one another, contributing to metabolic, structural, and transcriptional instability. Within this context, muscle wasting reflects not only loss of muscle mass or strength, but also loss of functional integrity resulting from disrupted integration of mechanical, metabolic, inflammatory, and anabolic signals. Given the systemic nature of these effects, this review proposes kinesitherapy as a potentially useful nonpharmacological adjunctive strategy that may modulate inflammation, restore responsiveness to mechanical stimuli, support calcium homeostasis and mitochondrial function, improve anabolic sensitivity, and maintain protein quality control. Overall, this review presents a systems-biology model of gastric cancer-associated muscle wasting and supports further investigation of exercise-based therapies for this condition. Full article

Natural products like the isoprenylated flavonoid Kuwanon G (KWG), isolated primarily from Morus alba, offer promising pleiotropic effects against multifactorial diseases, overcoming the limitations of conventional single-target synthetic drugs. This study aims to systematically review the pharmacological activities of KWG and evaluate its underlying molecular mechanisms. A comprehensive literature review was integrated with network pharmacology, protein–protein interaction (PPI) profiling, and KEGG/GO pathway enrichment analyses to identify shared targets across different pathologies. Experimental data demonstrate that KWG exhibits antimicrobial, anti-inflammatory, antidiabetic, neuroprotective, anti-obesity, and anticancer properties. Bioinformatics analyses revealed that KWG exerts these effects by modulating core targets (e.g., TNF, IL-6, SRC, RELA) and key signaling pathways, including NF-κB, PI3K/AKT/mTOR, and Toll-like receptors, which govern inflammation, oxidative stress, and metabolic regulation. In conclusion, KWG is a potent, multi-target compound with significant therapeutic potential for managing chronic and infectious diseases. However, future structure–activity relationship studies and clinical trials are required to address its pharmacokinetic limitations, such as low bioavailability, to facilitate its clinical translation. Full article

Xanthotoxin (8-methoxypsoralen) belongs to the group of naturally occurring furanocoumarin (furocoumarin) compounds and is a product of plant secondary metabolism. Analysis of the available literature indicates that xanthotoxin exhibits a broad spectrum of pharmacological activities, including anti-inflammatory, antioxidant, immunomodulatory, and antibacterial effects. Xanthotoxin has been shown to stimulate autophagy via inhibition of the AKT/mTOR pathway, as well as to block cell migration by modulating RIG-1 and NF-κB signaling. Moreover, its effects on JNK/MAPK, PI3K/AKT, Calcium–CaMYK/PYK2, and other signaling cascades have been confirmed. Among its most promising properties is the ability to inhibit ABC transporters, thereby preventing the reduction of chemotherapeutic agent concentrations within tumor cells and enhancing their intracellular accumulation. Thus, the aim of this study was to evaluate xanthotoxin as a potential anticancer agent. The literature review was based on publications indexed in Google Scholar, Scopus, Web of Science, and PubMed and published between 2010 and 2026. Studies describing the biological properties of xanthotoxin, its toxicity, anticancer mechanisms of action, and modulation of ABC transporters were included. This literature review summarizes the pharmacological profile of xanthotoxin, and its biological activities and therapeutic potential, as well as its antitumor effects in various cancer cell lines. The available evidence may provide a foundation for the future development of xanthotoxin as a lead compound for anticancer drug discovery. Full article

Background/Objectives: Rumex obtusifolius L. (Polygonaceae) has been traditionally used to treat various disorders, including hepatic and gastrointestinal diseases. However, the phytochemical constituents of its roots and their potential protective effects against skeletal muscle atrophy remain poorly understood. This study aimed to isolate and characterize bioactive constituents from R. obtusifolius roots and evaluate their protective effects against dexamethasone (DEX)-induced muscle atrophy in C2C12 myotubes. Methods: LC–MS-guided phytochemical investigation of the ethanol extract of R. obtusifolius roots, followed by successive column chromatography and HPLC purification, resulted in the isolation of four naphthalene-type glycosides. Their structures were elucidated using 1D and 2D NMR spectroscopy, HR-ESIMS, and chemical transformation. The protective effects of compounds 1 and 4 against dexamethasone (DEX)-induced muscle atrophy were evaluated by assessing myotube morphology, myogenic and atrophy-related protein expression, and PI3K/Akt/mTOR signaling. Results: A new naphthalene malonylglucoside, nepodin-8-O-β-D-(6′-O-malonyl)-glucopyranoside (1), together with three known glycosides (2–4), was identified. Among the isolated compounds, compound 1 significantly attenuated DEX-induced muscle atrophy in a concentration-dependent manner by increasing myotube diameter and improving myotube morphology. It restored the expression of the myogenic markers MyoD and myogenin while suppressing the atrophy-related proteins MuRF1 and MAFBX. Furthermore, compound 1 reversed DEX-induced suppression of the PI3K/Akt/mTOR signaling pathway, indicating recovery of anabolic signaling. Conclusions: This study reports a new naphthalene malonylglucoside (1) from R. obtusifolius roots and demonstrates that compound 1 protects against DEX-induced skeletal muscle atrophy through restoration of myogenic differentiation and activation of the PI3K/Akt/mTOR pathway. These findings suggest that compound 1 is a promising natural lead compound for the development of therapeutics targeting muscle wasting disorders. Full article

Metformin is a cornerstone medication for type 2 diabetes and exhibits anti-tumor activities. Previous studies have demonstrated that metformin suppresses tumor progression by regulating multiple signaling pathways, including the AMPK, PI3K/AKT/mTOR, and JNK pathways. However, most previous studies have focused on its direct effects on tumor cells, with limited attention to its effects in the TME. The TME constitutes a multifaceted ecosystem that drives tumor development and therapeutic resistance via physical barrier formation, immune evasion, and abnormal angiogenesis. In this review, we systematically summarize the impact and underlying regulatory mechanisms of metformin on distinct components of the TME. In addition, we discuss the individual and combined roles of metformin in immunity and inflammation, as well as vascular, matrix, and metabolic regulation. By elucidating the mechanisms of metformin-mediated TME reprogramming, we aim to provide new perspectives for understanding its anti-tumor effects and facilitating its clinical translation in cancer therapy. Full article

Cancer stem cells (CSCs) drive therapeutic resistance and tumor relapse by exploiting redundant regulatory networks that integrate Wnt/β-catenin, Notch, and Hedgehog signaling with metabolic reprogramming, epigenetic plasticity, and tumor microenvironment crosstalk, a network architecture that renders single-pathway inhibition strategies insufficient. This review systematically examines evidence that natural compounds (curcumin, sulforaphane, resveratrol, EGCG, berberine, and quercetin) act as multitarget modulators of CSC plasticity, analyzing their molecular mechanisms of action in specific cancer models. Each compound engages distinct regulatory nodes: curcumin suppresses β-catenin nuclear translocation and STAT3 phosphorylation in lung cancer CSC models; sulforaphane represses ΔNp63α-driven stemness transcription in colorectal cancer and reduces CSC self-renewal in prostate and head and neck models; resveratrol dissociates the β-catenin–GLI-1 interaction in oral and lung CSC populations and induces Wnt/β-catenin-dependent autophagy in breast CSCs; EGCG inhibits DNMT and HDAC activity in glioblastoma and colorectal models; berberine activates AMPK-mediated suppression of mTORC1 in colorectal cancer; and quercetin suppresses PI3K/AKT/mTOR signaling while downregulating EMT transcription factors in breast and colorectal systems. We critically assess persistent methodological limitations, including bulk cell-line models, supraphysiological concentrations, and the absence of functional tumor-initiating validation, that currently prevent stronger translational conclusions. Natural compounds from Latin American biodiversity are identified as an underexplored source of CSC-active molecules. We conclude by defining the experimental standards required to reposition natural compounds as clinically relevant network-level modulators of CSC plasticity. Full article

Neurodegenerative disorders such as Alzheimer’s disease (AD) and malignant neoplasms are among the most prevalent age-associated diseases worldwide. Although cancer is characterized by uncontrolled proliferation, resistance to apoptosis, and metabolic reprogramming, AD and other neurodegenerative disorders such as Lewy body disease (LBD) including Parkinson’s Disease (PD) and fronto-temporal lobar degeneration (FTLD) are defined by synaptic dysfunction, neuronal loss, neuroinflammation, and impaired proteostasis with misfolded protein aggregates. Despite these contrasting phenotypes, converging epidemiological and molecular data support an inverse relationship between cancer and neurodegenerative disorders, whereby a history of cancer is associated with reduced AD risk, whereas AD is linked to a lower incidence of multiple malignancies. These observations suggest that oncogenesis and neurodegeneration may represent divergent outcomes of shared biological processes dysregulated during aging. This conundrum likely reflects differential regulation of core cellular pathways governing cell survival, stress responses, metabolism, and genomic integrity but could also reflect the differential influence of aging pathways and secreted growth factors. Pro-survival and proliferative signaling pathways commonly activated in cancer, including PI3K–AKT–mTOR signaling, altered p53 function, enhanced DNA damage tolerance, and anabolic metabolism, are often impaired in AD, LBD and FTLD, where neurons exhibit heightened vulnerability to stress, mitochondrial dysfunction, defective autophagy, and activation of pro-apoptotic cascades. Conversely, tumor-suppressive mechanisms that restrain proliferation may protect against malignancy but increase susceptibility to degeneration in post-mitotic neurons. Aging-related processes such as cellular senescence, immune dysregulation, and loss of proteostasis may further exert divergent effects in oncogenesis and neurodegeneration. This review aims to clarify associations between specific cancer types and neurodegenerative disorders, examine shared and opposing selected molecular mechanisms linking specific cancers and neurodegeneration, and contextualize these relationships within broader aging pathways (e.g., cell senescence, proteostasis). By integrating epidemiological, mechanistic, and therapeutic perspectives, we highlight unifying biological principles and translational opportunities at the intersection of cancer, neurodegeneration, and aging. Full article

Autophagy was originally identified as a survival mechanism to allow cells to survive under nutrient-deprived or stressful conditions whereas cellular senescence was considered a tumor-suppressive mechanism. Both processes can be induced by similar stimuli and can influence each other. There have been continued debates about whether they are causally linked, whether autophagy promotes or prevents senescence or if they are independent of each other. Protein kinases play integral roles in cell fate decision and have a major influence on both autophagy and senescence. While mechanistic target of rapamycin complex 1 is considered the master regulator of autophagy, it also influences senescence. Mitogen-activated protein kinases originally associated with senescence can regulate autophagy. While there have been numerous review articles on the interplay between autophagy and senescence, a comprehensive review on how various kinases participate in this interplay is lacking. The purpose of this review is to learn lessons from some old and recent studies to understand how kinases contribute to this changing field. Since both autophagy and senescence can have beneficial and detrimental effects and kinases are important drug targets, insights regarding how kinases orchestrate these two processes should help develop therapeutic strategies to treat diseases, such as aging and cancer. Full article

Introduction: Optimal systemic treatment for recurrent or advanced endometrial cancer (EC) remains uncertain, particularly in the second-line setting. While first-line chemotherapy with paclitaxel and carboplatin is widely used, its efficacy is limited. Recent evidence suggests that adding immune checkpoint inhibitors (ICIs) to chemotherapy (ChT) can improve progression-free survival (PFS). In addition, hormonal therapies (such as progestins and aromatase inhibitors), targeted therapies and ICIs used alone or in combination are emerging as potential treatment options. Objectives: Our objective was to systematically evaluate the efficacy and safety of systemic therapies beyond standard ChT for patients with recurrent or advanced EC, focusing on progression-free survival (PFS), overall survival (OS), and treatment-related adverse events (TRAEs). Methods: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), prospective studies, and retrospective studies up to June 2024 on PubMed, Embase, and CENTRAL. Studies evaluating systemic therapies—chemotherapy, hormonal therapy, targeted agents, and ICIs—in recurrent or advanced EC were included. Primary outcomes were PFS and OS; secondary outcomes included grade ≥ 3 treatment-related adverse events. Risk of bias was assessed using the Cochrane RoB 2 and MINORS tools, and GRADE was applied to evaluate the certainty of evidence. Results: Five RCTs evaluated the addition of ICI to conventional ChT. In mismatch repair-deficient (MMRd) patients, the addition of ICI significantly improved PFS and OS compared to the ChT-only group. In mismatch repair-deficient (MMRd) patients, the median PFS (mPFS) was 8.39 months in the ChT group and 22.73 months in the ICI group (HR: 0.34, p < 0.001). OS results were 26.48 and 41.36 months, respectively. In mismatch repair-proficient (MMRp) patients, mPFS was 9.4 months in the ChT group and 10.18 months at the ICI group (HR: 0.72, p = 0.002). OS was 27.37 and 27.79 months, respectively. We conducted several exploratory single-arm subgroup analyses and multiple individual patient data (IPD) meta-analyses across several clinically relevant subgroups, including patients treated with progestins, lenvatinib plus pembrolizumab, PI3K/AKT/mTOR inhibitor monotherapy, and PI3K/AKT/mTOR inhibitors in combination with aromatase inhibitors. Detailed descriptive analyses were performed for each subgroup. Conclusions: Combining chemotherapy with ICIs appears to show the most favorable survival outcomes, especially in MMRd tumors. Taking into account the methodological limitations inherent in the elaboration of lower-level evidence and IPD, hormonal and targeted therapies might be considered viable options, with efficacy and safety profiles dependent on tumor biology. Better stratification of the EC patient cohort is warranted. Full article