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Aims: In diabetes, hyperglycemia increases reactive oxygen species that induce DNA damage and poly(ADP-ribose)polymerase activation. The aim of this study is to characterize the proteomic profile and the role of poly(ADP-ribosylation) in patients with type 2 diabetes. Methods: A proteomic platform based on 2DE and MALDI-ToF spectrometry was applied to peripheral blood mononuclear cells obtained from two different cohorts in which diabetic ( n = 14) and normoglycemic patients ( n = 11) were enrolled. Results: Proteomic maps identified WD repeat protein, 78-kDa glucose-regulated protein precursor and myosin regulatory light chain 2, as unique proteins in diabetic patients; vimentin, elongation factor 2, annexin A1, glutathione S-transferase P, moesin and cofilin-1 as unique in the normoglycemic; and calreticulin, rho GDP-dissociation inhibitor 2, protein disulfide isomerase and tropomyosin alpha-4-chain as differentially expressed between the two cohorts. An enrichment in PARylation in diabetic patients was observed in particular, affecting GAPDH and α-Enolase leading to a decrease in their enzymatic activity. Conclusions: As the GAPDH and α-Enolase are involved in energy metabolism, protein synthesis and DNA repair, loss of their function or change in their activity can significantly contribute to the molecular mechanisms responsible for the development of type 2 diabetes. These data along with the proteomic profile associated with the disease may provide new insight into the pathophysiology of type 2 diabetes. [ABSTRACT FROM AUTHOR]

This article considers a special kind of surprise questions, i.e. those introduced by the adversative particle ma (but), and compares it with surprise exclamations. The main issue addressed here concerns the obligatory presence in the questions of the imperfect verbal form, versus the obligatory presence in exclamations of a non-imperfect indicative. It will be shown that the special semantics associated with these structures determines the presence of a certain verbal form. Some syntactic issues will be addressed in the final section, having to do with the representation in the syntax of properties connected to the context. [ABSTRACT FROM AUTHOR]

Tauopathies, including Alzheimer's disease and Frontotemporal Dementia, are debilitating neurodegenerative disorders marked by cognitive decline. Despite extensive research, achieving effective treatments and significant symptom management remains challenging. Accurate diagnosis is crucial for developing effective therapeutic strategies, with hyperphosphorylated protein units and tau oligomers serving as reliable biomarkers for these conditions. This study introduces a novel approach using nanotechnology to enhance the diagnostic process for tauopathies. We developed humanized ferritin nanocages, a novel nanoscale delivery system, designed to encapsulate and transport a tau-specific fluorophore, BT1, into human retinal cells for detecting neurofibrillary tangles in retinal tissue, a key marker of tauopathies. The delivery of BT1 into living cells was successfully achieved through these nanocages, demonstrating efficient encapsulation and delivery into retinal cells derived from human induced pluripotent stem cells. Our experiments confirmed the colocalization of BT1 with pathological forms of tau in living retinal cells, highlighting the method's potential in identifying tauopathies. Using ferritin nanocages for BT1 delivery represents a significant contribution to nanobiotechnology, particularly in neurodegenerative disease diagnostics. This method offers a promising tool for the early detection of tau tangles in retinal tissue, with significant implications for improving the diagnosis and management of tauopathies. This study exemplifies the integration of nanotechnology with biomedical science, expanding the frontiers of nanomedicine and diagnostic techniques. [ABSTRACT FROM AUTHOR]

Chronic lymphocytic leukemia (CLL) is a widespread type of leukemia that predominantly targets B lymphocytes, undermining the balance between cell proliferation and apoptosis. In healthy B cells, miR-15/16, a tandem of microRNAs, functions as a tumor suppressor, curbing the expression of the antiapoptotic B cell lymphoma 2 protein (Bcl-2). Conversely, in CLL patients, a recurring deletion on chromosome 13q14, home to the miR15-a and miR16-1 genes, results in Bcl-2 overexpression, thereby fostering the onset of the pathology. In the present research, a novel approach utilizing humanized ferritin-based nanoparticles was employed to successfully deliver miR15-a and miR-16-1 into MEG01 cells, a model characterized by the classic CLL deletion and overexpression of the human ferritin receptor (TfR1). The loaded miR15-a and miR16-1, housed within modified HumAfFt, were efficiently internalized via the MEG01 cells and properly directed into the cytoplasm. Impressively, the concurrent application of miR15-a and miR16-1 demonstrated a robust capacity to induce apoptosis through the reduction in Bcl-2 expression levels. This technology, employing RNA-loaded ferritin nanoparticles, hints at promising directions in the battle against CLL, bridging the substantial gap left by traditional transfection agents and indicating a pathway that may offer hope for more effective treatments. [ABSTRACT FROM AUTHOR]

Phosphodiesterases (PDEs) are a superfamily of evolutionarily conserved cyclic nucleotide (cAMP/cGMP)-hydrolyzing enzymes, components of transduction pathways regulating crucial aspects of cell life. Within this family, the cGMP-dependent PDE5 is the major hydrolyzing enzyme in many mammalian tissues, where it regulates a number of cellular and tissular processes. Using Kluyveromyces lactis as a model organism, the murine PDE5A1, A2 and A3 isoforms were successfully expressed and studied, evidencing, for the first time, a distinct role of each isoform in the control, modulation and maintenance of the cellular redox metabolism. Moreover, we demonstrated that the short N-terminal peptide is responsible for the tetrameric assembly of MmPDE5A1 and for the mitochondrial localization of MmPDE5A2. We also analyzed MmPDE5A1, A2 and A3 using small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), structural mass spectrometry (MS) and polyacrylamide gel electrophoresis in their native conditions (native-PAGE) and in the presence of redox agents. These analyses pointed towards the role of a few specific cysteines in the isoforms' oligomeric assembly and the loss of enzymatic activity when modified. [ABSTRACT FROM AUTHOR]

The high-energy 3′,5′phosphodiester linkages conservedin 3′,5′ cyclic GMPs offer a genuine solution for monomeractivation required by the transphosphorylation reactions that couldlead to the emergence of the first simple oligonucleotide sequenceson the early Earth. In this work we provide an in-depth characterizationof the effect of the reaction conditions on the yield of the polymerizationreaction of 3′,5′ cyclic GMPs both in aqueous environmentas well as under dehydrating conditions. We show that the thresholdtemperature of the polymerization is about 30 °C lower underdehydrating conditions than in solution. In addition, we present aplausible exergonic reaction pathway for the polymerization reaction,which involves transient formation of anionic centers at the O3′positions of the participating riboses. We suggest that excess Na+cations inhibit the polymerization reaction because theyblock the anionic mechanism via neutralizing the negatively chargedO3′. Our experimental findings are compatible with a prebioticscenario, where gradual desiccation of the environment could inducepolymerization of 3′,5′ cyclic GMPs synthesized in liquid. [ABSTRACT FROM AUTHOR]

Among natural products under investigation for their additive potential in cancer prevention and treatment, the flavonoid quercetin has received attention for its effects on the cell cycle arrest and apoptosis. In the past, we addressed this issue in K562 cells, a cellular model of the human chronic myeloid leukemia. Here, we applied stable isotope labeling by amino acids in cell culture (SILAC) proteomics with the aim to increase knowledge on the regulative and metabolic pathways modulated by quercetin in these cells. After 24 h of quercetin treatment, we observed that apoptosis was not completely established, thus we selected this time range to capture quantitative data. As a result, we were able to achieve a robust identification of 1703 proteins, and to measure fold changes between quercetin-treated and untreated cells for 1206 proteins. Through a bioinformatics functional analysis on a subset of 112 proteins, we propose that the apoptotic phenotype of K562 cells entails a significant modulation of the translational machinery, RNA metabolism, antioxidant defense systems, and enzymes involved in lipid metabolism. Finally, we selected eight differentially expressed proteins, validated their modulated expression in quercetin-treated K562 cells, and discussed their possible role in flavonoid cytotoxicity. This quantitative profiling, performed for the first time on this type of tumor cells upon treatment with a flavonoid, will contribute to revealing the molecular basis of the multiplicity of the effects selectively exerted by quercetin on K562 cells. [ABSTRACT FROM AUTHOR]

Amyloid-treated microglia prime and sustain neuroinflammatory processes in the central nervous system activating different signalling pathways inside the cells. Since a key role for PARP-1 has been demonstrated in inflammation and in neurodegeneration, we investigated PARylated proteins in resting and in β-amyloid peptide treated BV2 microglial cells. A total of 1158 proteins were identified by mass spectrometry with 117 specifically modified in the amyloid-treated cells. Intervention of PARylation on the proteome of microglia showed to be widespread in different cellular districts and to affect various cellular pathways, highlighting the role of this dynamic post-translational modification in cellular regulation. Ubiquitination is one of the more enriched pathways, encompassing PARylated proteins like NEDD4, an E3 ubiquitine ligase and USP10, a de-ubiquitinase, both associated with intracellular responses induced by β-amyloid peptide challenge. PARylation of NEDD4 may be involved in the recruiting of this protein to the plasma membrane where it regulates the endocytosis of AMPA receptors, whereas USP10 may be responsible for the increase of p53 levels in amyloid stimulated microglia. Unfolded protein response and Endoplasmic Reticulum Stress pathways, strictly correlated with the Ubiquitination process, also showed enrichment in PARylated proteins. PARylation may thus represent one of the molecular switches responsible for the transition of microglia towards the inflammatory microglia phenotype, a pivotal player in brain diseases including neurodegenerative processes. The establishment of trials with PARP inhibitors to test their efficacy in the containment of neurodegenerative diseases may be envisaged. [ABSTRACT FROM AUTHOR]

Aims: Among the putative mechanisms proposed to be common factors in Down syndrome (DS) and Alzheimer's disease (AD) neuropathology, deficits in protein quality control (PQC) have emerged as a unifying mechanism of neurodegeneration. Considering that disturbance of protein degradation systems is present in DS and that oxidized/misfolded proteins require polyubiquitinylation for degradation via the ubiquitin proteasome system, this study investigated if dysregulation of protein polyubiquitinylation is associated with AD neurodegeneration in DS. Results: Postmortem brains from DS cases before and after development of AD neuropathology and age-matched controls were analyzed. By selectively isolating polyubiquitinated proteins, we were able to identify specific proteins with an altered pattern of polyubiquitinylation as a function of age. Interestingly, we found that oxidation is coupled with polyubiquitinylation for most proteins mainly involved in PQC and energy metabolism. Innovation: This is the first study showing alteration of the polyubiquitinylation profile as a function of aging in DS brain compared with healthy controls. Understanding the onset of the altered ubiquitome profile in DS brain may contribute to identification of key molecular regulators of age-associated cognitive decline. Conclusions: Disturbance of the polyubiquitinylation machinery may be a key feature of aging and neurodegeneration. In DS, age-associated deficits of the proteolytic system may further exacerbate the accumulation of oxidized/misfolded/polyubiquitinated proteins, which is not efficiently degraded and may become harmful to neurons and contribute to AD neuropathology. Antioxid. Redox Signal. 26, 280-298. [ABSTRACT FROM AUTHOR]

Genome polymorphisms are responsible for phenotypic differences between humans and for individual susceptibility to genetic diseases and therapeutic responses. Non-synonymous single-nucleotide polymorphisms (nsSNPs) lead to protein variants with a change in the amino acid sequence that may affect the structure and/or function of the protein and may be utilized as efficient structural and functional markers of association to complex diseases. This study is focused on nsSNP variants of the ligand binding domain of PPARγ a nuclear receptor in the superfamily of ligand inducible transcription factors that play an important role in regulating lipid metabolism and in several processes ranging from cellular differentiation and development to carcinogenesis. Here we selected nine nsSNPs variants of the PPAR ligand binding domain, V290M, R357A, R397C, F360L, P467L, Q286P, R288H, E324K, and E460K, expressed in cancer tissues and/or associated with partial lipodystrophy and insulin resistance. The effects of a single amino acid change on the thermodynamic stability of PPAR, its spectral properties, and molecular dynamics have been investigated. The nsSNPs PPAR variants show alteration of dynamics and tertiary contacts that impair the correct reciprocal positioning of helices 3 and 12, crucially important for PPAR functioning. [ABSTRACT FROM AUTHOR]

The cytosolic and mitochondrial isoforms of serine hydroxymethyltransferase (SHMT1 and SHMT2, respectively) are well-recognized targets of cancer research, since their activity is critical for purine and pyrimidine biosynthesis and because of their prominent role in the metabolic reprogramming of cancer cells. Here we show that 3-bromopyruvate (3BP), a potent novel anti -tumour agent believed to function primarily by blocking energy metabolism, differentially inactivates human SHMT1 and SHMT2. SHMT1 is completely inhibited by 3BP, whereas SHMT2 retains a significant fraction of activity. Site directed mutagenesis experiments on SHMT1 demonstrate that selective inhibition relies on the presence of a cysteine residue at the active site of SHMT1 (Cys204) that is absent in SHMT2. Our results show that 3BP binds to SHMT1 active site, forming an enzyme-3BP complex, before reacting with Cys204. The physiological substrate l -serine is still able to bind at the active site of the inhibited enzyme, although catalysis does not occur. Modelling studies suggest that alkylation of Cys204 prevents a productive binding of l -serine, hampering interaction between substrate and Arg402. Conversely, the partial inactivation of SHMT2 takes place without the formation of a 3BP-enzyme complex. The introduction of a cysteine residue in the active site of SHMT2 by site directed mutagenesis (A206C mutation), at a location corresponding to that of Cys204 in SHMT1, yields an enzyme that forms a 3BP-enzyme complex and is completely inactivated. This work sets the basis for the development of selective SHMT1 inhibitors that target Cys204, starting from the structure and reactivity of 3BP. [ABSTRACT FROM AUTHOR]

Background Several studies suggest that pathological changes in Alzheimer’s disease (AD) brain begin around 10–20 years before the onset of cognitive impairment. Biomarkers that can support early diagnosis and predict development of dementia would, therefore, be crucial for patient care and evaluation of drug efficacy. Although cerebrospinal fluid (CSF) levels of Aβ42, tau, and p-tau are well-established diagnostic biomarkers of AD, there is an urgent need to identify additional molecular alterations of neuronal function that can be evaluated at the systemic level. Objectives This study was focused on the analysis of oxidative stress-related modifications of the CSF proteome, from subjects with AD and amnestic mild cognitive impairment (aMCI). Methods A targeted proteomics approach has been employed to discover novel CSF biomarkers that can augment the diagnostic and prognostic accuracy of current leading CSF biomarkers. CSF samples from aMCI, AD and control individuals (CTR) were collected and analyzed using a combined redox proteomics approach to identify the specific oxidatively modified proteins in AD and aMCI compared with controls. Results The majority of carbonylated proteins identified by redox proteomics are found early in the progression of AD, i.e., oxidatively modified CSF proteins were already present in aMCI compared with controls and remain oxidized in AD, thus suggesting that dysfunction of selected proteins initiate many years before severe dementia is diagnosed. Conclusions The above findings highlight the presence of early oxidative damage in aMCI before clinical dementia of AD is manifested. The identification of early markers of AD that may be detected peripherally may open new prospective for biomarker studies. [ABSTRACT FROM AUTHOR]

Rosemary (Rosmarinus officinalis L.) has been used since ancient times in traditional medicine, while nowadays various rosemary formulations are increasingly exploited by alternative medicine to cure or prevent a wide range of health disorders. Rosemary’s bioproperties have prompted scientific investigation, which allowed us to ascertain antioxidant, anti-inflammatory, cytostatic, and cytotoxic activities of crude extracts or of pure components. Although there is a growing body of experimental work, information about rosemary’s anticancer properties, such as chemoprotective or anti-proliferative effects on cancer cells, is very poor, especially concerning the mechanism of action. Melanoma is a skin tumor whose diffusion is rapidly increasing in the world and whose malignancy is reinforced by its high resistance to cytotoxic agents; hence the availability of new cytotoxic drugs would be very helpful to improve melanoma prognosis. Here we report on the effect of a rosemary hydroalcoholic extract on the viability of the human melanoma A375 cell line. Main components of rosemary extract were identified by liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) and the effect of the crude extract or of pure components on the proliferation of cancer cells was tested by MTT and Trypan blue assays. The effect on cell cycle was investigated by using flow cytometry, and the alteration of the cellular redox state was evaluated by intracellular ROS levels and protein carbonylation analysis. Furthermore, in order to get information about the molecular mechanisms of cytotoxicity, a comparative proteomic investigation was performed. [ABSTRACT FROM AUTHOR]

A common feature of non-coding repeat expansion disorders is the accumulation of RNA repeats as RNA foci in the nucleus and/or cytoplasm of affected cells. These RNA foci can be toxic because they sequester RNA-binding proteins, thus affecting various steps of post-transcriptional gene regulation. However, the precise step that is affected by C9orf72 GGGGCC (G4C2) repeat expansion, the major genetic cause of amyotrophic lateral sclerosis (ALS), is still poorly defined. In this work, we set out to characterise these mechanisms by identifying proteins that bind to C9orf72 RNA. Sequestration of some of these factors into RNA foci was observed when a (G4C2)31 repeat was expressed in NSC34 and HeLa cells. Most notably, (G4C2)31 repeats widely affected the distribution of Pur-alpha and its binding partner fragile X mental retardation protein 1 (FMRP, also known as FMR1), which accumulate in intra-cytosolic granules that are positive for stress granules markers. Accordingly, translational repression is induced. Interestingly, this effect is associated with a marked accumulation of poly(A) mRNAs in cell nuclei. Thus, defective trafficking of mRNA, as a consequence of impaired nuclear mRNA export, might affect translation efficiency and contribute to the pathogenesis of C9orf72 ALS. [ABSTRACT FROM AUTHOR]

Adaptive metabolic reprogramming gives cancer cells a proliferative advantage. Tumour cells extensively use glycolysis to sustain anabolism and produce serine, which not only refuels the one-carbon units necessary for the synthesis of nucleotide precursors and for DNA methylation, but also affects the cellular redox homeostasis. Given its central role in serine metabolism, serine hydroxymethyltransferase ( SHMT), a pyridoxal 5′-phosphate ( PLP)-dependent enzyme, is an attractive target for tumour chemotherapy. In humans, the cytosolic isoform ( SHMT1) and the mitochondrial isoform ( SHMT2) have distinct cellular roles, but high sequence identity and comparable catalytic properties, which may complicate development of successful therapeutic strategies. Here, we investigated how binding of the cofactor PLP controls the oligomeric state of the human isoforms. The fact that eukaryotic SHMTs are tetrameric proteins while bacterial SHMTs function as dimers may suggest that the quaternary assembly in eukaryotes provides an advantage to fine-tune SHMT function and differentially regulate intertwined metabolic fluxes, and may provide a tool to address the specificity problem. We determined the crystal structure of SHMT2, and compared it to the apo-enzyme structure, showing that PLP binding triggers a disorder-to-order transition accompanied by a large rigid-body movement of the two cofactor-binding domains. Moreover, we demonstrated that SHMT1 exists in solution as a tetramer, both in the absence and presence of PLP, while SHMT2 undergoes a dimer-to-tetramer transition upon PLP binding. These findings indicate an unexpected structural difference between the two human SHMT isoforms, which opens new perspectives for understanding their differing behaviours, roles or regulation mechanisms in response to PLP availability in vivo. [ABSTRACT FROM AUTHOR]

The peroxisome proliferator-activated receptors (PPARs) are transcription factors that regulate glucose and lipid metabolism. The role of PPARs in several chronic diseases such as type 2 diabetes, obesity and atherosclerosis is well known and, for this reason, they are the targets of antidiabetic and hypolipidaemic drugs. In the last decade, some rare mutations in human PPARγ that might be associated with partial lipodystrophy, dyslipidaemia, insulin resistance and colon cancer have emerged. In particular, the F360L mutant of PPARγ (PPARγ2 residue 388), which is associated with familial partial lipodystrophy, significantly decreases basal transcriptional activity and impairs stimulation by synthetic ligands. To date, the structural reason for this defective behaviour is unclear. Therefore, the crystal structure of PPARγ F360L together with the partial agonist LT175 has been solved and the mutant has been characterized by circular-dichroism spectroscopy (CD) in order to compare its thermal stability with that of the wild-type receptor. The X-ray analysis showed that the mutation induces dramatic conformational changes in the C-terminal part of the receptor ligand-binding domain (LBD) owing to the loss of van der Waals interactions made by the Phe360 residue in the wild type and an important salt bridge made by Arg357, with consequent rearrangement of loop 11/12 and the activation function helix 12 (H12). The increased mobility of H12 makes the binding of co-activators in the hydrophobic cleft less efficient, thereby markedly lowering the transactivation activity. The spectroscopic analysis in solution and molecular-dynamics (MD) simulations provided results which were in agreement and consistent with the mutant conformational changes observed by X-ray analysis. Moreover, to evaluate the importance of the salt bridge made by Arg357, the crystal structure of the PPARγ R357A mutant in complex with the agonist rosiglitazone has been solved. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune disease and rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA) are the most frequently detected autoantibodies (autoAbs). To date, more than 20% of RA cases are still defined as seronegative forms (seronegative RA, SN-RA). The aim of this study was to identify new antigenic targets of autoAbs in RA patients, which can also be recognized in SN-RA. Using a proteomic approach, we tested sera from SN-RA patients by analyzing synovial fluid (SF) proteins from these patients. Sera from SN-RA patients revealed a strong reactive spot, corresponding to alpha 1 antitrypsin (A1AT). Reverse-phase nanoliquid chromatography and tandem mass spectrometry (Matrix Assisted Laser Desorption/Ionization-Time Of Flight, MALDI-TOF/TOF) confirmed the presence of A1AT in SF and showed that homocysteinylation was one of the post-translational modifications of A1AT. Homocysteinylated (Hcy)-A1AT immunoprecipitated from SN-RA patients' SFs and in vitro modified Hcy-A1AT were used as antigens by Enzyme-Linked ImmunoSorbent Assay (ELISA) to test the presence of specific autoAbs in sera from 111 SN-RA patients, 132 seropositive (SP)-RA patients, and from 95 patients with psoriatic arthritis, 40 patients with osteoarthritis, and 41 healthy subjects as control populations. We observed that a large portion of SN-RA patients (75.7%), and also most of SP-RA patients' sera (87.1%) displayed anti-Hcy-A1AT autoAbs (anti-HATA). Native A1AT was targeted at a lower rate by SP-RA patients autoAbs, while virtually no SN-RA patients' sera showed the presence of anti-native A1AT autoAbs. In conclusion, anti-HATA can be considered potential biomarkers for RA, also in the SN forms. The discovery of novel autoAbs targeting specific autoantigens can represent higher clinic significance for all RA patients' population. Image 1 • RF and ACPA in patients' sera are biomarkers used for the diagnosis of RA. • More than 20% of RA cases are still defined as seronegative forms (SN-RA). • By a proteomic approach, homocysteinylated (Hcy)-A1AT was detected in the synovial fluid of SN-RA patients. • ELISA showed specific autoAbs towards Hcy-A1AT in SN-RA patients' sera. [ABSTRACT FROM AUTHOR]

The β-amyloid (Aβ) peptide plays a key role in the pathogenesis of Alzheimer's disease. The methionine (Met) residue at position 35 in Aβ C-terminal domain is critical for neurotoxicity, aggregation, and free radical formation initiated by the peptide. The role of Met in modulating toxicological properties of Aβ most likely involves an oxidative event at the sulfur atom. We therefore investigated the one- or two-electron oxidation of the Met residue of Aβ25-35 fragment and the effect of such oxidation on the behavior of the peptide. Bicarbonate promotes two-electron oxidations mediated by hydrogen peroxide after generation of peroxymonocarbonate (HCO4−, PMC). The bicarbonate/carbon dioxide pair stimulates one-electron oxidations mediated by carbonate radical anion (CO3•−). PMC efficiently oxidizes thioether sulfur of the Met residue to sulfoxide. Interestingly, such oxidation hampers the tendency of Aβ to aggregate. Conversely, CO3•− causes the one-electron oxidation of methionine residue to sulfur radical cation (MetS•+). The formation of this transient reactive intermediate during Aβ oxidation may play an important role in the process underlying amyloid neurotoxicity and free radical generation. [ABSTRACT FROM AUTHOR]

STAT3 is an oncoprotein overexpressed in different types of tumors, including prostate cancer (PCa), and its activity is modulated by a variety of post-translational modifications (PTMs). Prostate cancer represents the most common cancer diagnosed in men, and each phase of tumor progression displays specific cellular conditions: inflammation is predominant in tumor's early stage, whereas oxidative stress is typical of clinically advanced PCa. The aim of this research is to assess the correspondence between the stimulus-specificity of STAT3 PTMs and definite STAT3-mediated transcriptional programs, in order to identify new suitable pharmacological targets for PCa treatment. Experiments were performed on less-aggressive LNCaP and more aggressive DU-145 cell lines, simulating inflammatory and oxidative-stress conditions. Cellular studies confirmed pY705-STAT3 as common denominator of all STAT3-mediated signaling. In addition, acK685-STAT3 was found in response to IL-6, whereas glutC328/542-STAT3 and pS727-STAT3 occurred upon tert-butyl hydroperoxyde (tBHP) treatment. Obtained results also provided evidence of an interplay between STAT3 PTMs and specific protein interactors such as P300 and APE1/Ref-1. In accordance with these outcomes, mRNA levels of STAT3-target genes seemed to follow the differing STAT3 PTMs. These results highlighted the role of STAT3 and its PTMs as drivers in the progression of PCa. [ABSTRACT FROM AUTHOR]