Delineation of crosstalk between HSP27 and MMP-2/MMP-9: A synergistic therapeutic avenue for glioblastoma management

Exploring the multi-targeting phytoestrogen potential of Calycosin for cancer treatment: A review

Cancer remains a significant challenge in the field of oncology, with the search for novel and effective treatments ongoing. Calycosin (CA), a phytoestrogen derived from traditional Chinese medicine, has garnered attention as a promising candidate. With its high targeting and low toxicity profile, CA has demonstrated medicinal potential across various diseases, including cancers, inflammation, and cardiovascular disease. Studies have revealed that CA possesses inhibitory effects against a diverse array of cancers. The underlying mechanism of action involves a reduction in tumor cell proliferation, induction of tumor cell apoptosis, and suppression of tumor cell migration and invasion. Furthermore, CA has been shown to enhance the efficacy of certain chemotherapeutic drugs, making it a potential component in treating malignant tumors. Given its high efficacy, low toxicity, and multi-targeting characteristics, CA holds considerable promise as a therapeutic agent for cancer treatment. The objective of this review is to present a synthesis of the current understanding of the antitumor mechanism of CA and its research progress.

HSP27 promotes vasculogenic mimicry formation in human salivary adenoid cystic carcinoma via the AKT-MMP-2/9 pathway

PURPOSE

To explore the role and mechanism of heat shock protein 27 (HSP27) in SACC VM formation.

STUDY DESIGN

Immunohistochemistry and double staining with cluster of differentiation 31 (CD31) and periodic acid-Schiff (PAS) were used to detect HSP27 expression and VM in 70 SACC tissue samples separately. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot analysis, and immunofluorescence were used to detect gene and protein expression. HSP27 in SACC cells were overexpression or downregulated by transfecting HSP27 or short hairpin RNA target HSP27 (sh-HSP27). The migration and invasion abilities of SACC cells were detected using wound healing and Transwell invasion assays. The VM formation ability of the cells in vitro was detected using a Matrigel 3-dimensional culture.

RESULTS

HSP27 expression was positively correlated with VM formation and affected the prognosis of patients. In vitro, HSP27 upregulation engendered VM formation and the invasion and migration of SACC cells. Mechanistically, HSP27 upregulation increased Akt phosphorylation and subsequently increased downstream matrix metalloproteinase 2 and 9 expressions.

CONCLUSION

HSP27 may plays an important role in VM formation in SACC via the AKT-MMP-2/9 signalling pathway.

Deciphering the Lexicon of Protein Targets: A Review on Multifaceted Drug Discovery in the Era of Artificial Intelligence

Understanding protein sequence and structure is essential for understanding protein-protein interactions (PPIs), which are essential for many biological processes and diseases. Targeting protein binding hot spots, which regulate signaling and growth, with rational drug design is promising. Rational drug design uses structural data and computational tools to study protein binding sites and protein interfaces to design inhibitors that can change these interactions, thereby potentially leading to therapeutic approaches. Artificial intelligence (AI), such as machine learning (ML) and deep learning (DL), has advanced drug discovery and design by providing computational resources and methods. Quantum chemistry is essential for drug reactivity, toxicology, drug screening, and quantitative structure-activity relationship (QSAR) properties. This review discusses the methodologies and challenges of identifying and characterizing hot spots and binding sites. It also explores the strategies and applications of artificial-intelligence-based rational drug design technologies that target proteins and protein-protein interaction (PPI) binding hot spots. It provides valuable insights for drug design with therapeutic implications. We have also demonstrated the pathological conditions of heat shock protein 27 (HSP27) and matrix metallopoproteinases (MMP2 and MMP9) and designed inhibitors of these proteins using the drug discovery paradigm in a case study on the discovery of drug molecules for cancer treatment. Additionally, the implications of benzothiazole derivatives for anticancer drug design and discovery are deliberated.

Acetogenins-Rich Fractions of Annona coriacea Suppress Human Glioblastoma Viability and Migration by Regulating Necroptosis and MMP-2 Activity In Vitro

Glioblastoma (GBM) is an incurable primary brain tumor with a poor prognosis. Resection, radiation therapy, and temozolomide (TMZ) are insufficient to increase survival, making the treatment limited. Thus, the search for more effective and specific treatments is essential, making plants a promising source for elucidating new anti-glioblastoma compounds. Accordingly, this study investigated the effects of four fractions of hexane and ethyl acetate extract of Annona coriacea Mart., enriched with acetogenins, against GBM cell lines. All four fractions were selectively cytotoxic to GBM cells when compared to TMZ. Moreover, A. coriacea fractions delayed cell migration; reduced cytoplasmic projections, the metalloproteinase 2 (MMP-2) activity; and induced morphological changes characteristic of necroptosis, possibly correlated with the increase in receptor-interacting protein kinase 1 and 3 (RIP-1 and RIP-3), apoptosis-inducing factor (AIF), and the non-activation of cleaved caspase 8. The present findings reinforce that fractions of A. coriacea Mart. should be considered for more studies focusing treatment of GBM.

Untangling the complexity of heat shock protein 27 in cancer and metastasis

Heat shock protein 27 is a type of molecular chaperone whose expression gets up-regulated due to reaction towards different stressful triggers including anticancer treatments. It is known to be a major player of resistance development in cancer cells, whereby cells are sheltered against the therapeutics that normally activate apoptosis. Heat shock protein 27 (HSP27) is one of the highly expressed proteins during various cellular insults and is a strong tumor survival factor. HSP27 influences various cellular pathways associated with cancer cell survival and growth such as apoptosis, autophagy, metastasis, angiogenesis, epithelial to mesenchymal transition, etc. HSP27 is molecular machinery which prevents the clumping of numerous substrates or client proteins which get mutated in cancer. It has been reported in several studies that targeting HSP27 is difficult because of its dynamic structure and absence of an ATP-binding site. Here, in this review, we have summarized different modulators of HSP27 and their mechanism of action as well. Effect of deregulated HSP27 in various cancer models, limitations of targeting HSP27, resistance against the conventional drugs generated due to the overexpression of HSP27, and measures to counteract this effect have also been discussed here in detail.

CoQ10 reduces glioblastoma growth and infiltration through proteome remodeling and inhibition of angiogenesis and inflammation

PURPOSE

Most monotherapies available against glioblastoma multiforme (GBM) target individual hallmarks of this aggressive brain tumor with minimal success. In this article, we propose a therapeutic strategy using coenzyme Q10 (CoQ10) as a pleiotropic factor that crosses the blood-brain barrier and accumulates in cell membranes acting as an antioxidant, and in mitochondrial membranes as a regulator of cell bioenergetics and gene expression.

METHODS

Xenografts of U251 cells in nu/nu mice were used to assay tumor growth, hypoxia, angiogenesis, and inflammation. An orthotopic model was used to explore microglial infiltration, tumor growth, and invasion into the brain parenchyma. Cell proliferation, migration, invasion, proteome remodeling, and secretome were assayed in vitro. Conditioned media were used to assay angiogenesis, monocyte chemoattraction, and differentiation into macrophages in vitro.

RESULTS

CoQ10 treatment decreased tumor volume in xenografts and orthotopic models, although its effect on tumor cell proliferation was not direct. Tumors from mice treated with CoQ10 were less hypoxic and vascularized, having less infiltration from inflammatory cells. Treatment-induced downregulation of HIF-1α and NF-kB led to a complete remodeling of the tumor cells proteome and secretome, impacting angiogenesis, monocyte infiltration, and their differentiation into macrophages. Besides, tumor cell migration and invasion were drastically restricted by mechanisms involving modulation of the actin cytoskeleton and downregulation of matrix metalloproteases (MMPs).

CONCLUSIONS

CoQ10 has a pleiotropic effect on GBM growth, targeting several hallmarks simultaneously. Thus, its integration into current treatments of this fatal disease should be considered.

Human prion protein: exploring the thermodynamic stability and structural dynamics of its pathogenic mutants

Human familial prion diseases are known to be associated with different single-point mutants of the gene coding for prion protein with a primary focus at several locations of the globular domain. We have identified 12 different single-point pathogenic mutants of human prion protein (HuPrP) with the help of extensive perturbations/mutation technique at multiple locations of HuPrP sequence related to potentiality towards conformational disorders. Among these, some of the mutants include pathogenic variants that corroborate well with the literature reported proteins while majority include some unique single-point mutants that are either not explicitly studied early or studied for variants with different residues at the specific position. Primarily, our study sheds light on the unfolding mechanism of the above mentioned mutants in depth. Besides, we could identify some mutants under investigation that demonstrates not only unfolding of the helical structures but also extension and generation of the β-sheet structures and or simultaneously have highly exposed hydrophobic surface which is assumed to be linked with the production of aggregate/fibril structures of the prion protein. Among the identified mutants, Q212E needs special attention due to its maximum exposure of hydrophobic core towards solvent and E200Q is found to be important due to its maximum extent of β-content. We are also able to identify different respective structural conformations of the proteins according to their degree of structural unfolding and those conformations can be extracted and further studied in detail. Communicated by Ramaswamy H. Sarma.

Discovery of Novel HSP27 Inhibitors as Prospective Anti-Cancer Agents Utilizing Computer-Assisted Therapeutic Discovery Approaches

Heat shock protein 27 (HSP27) is a protein that works as a chaperone and an antioxidant and is activated by heat shock, environmental stress, and pathophysiological stress. However, HSP27 dysregulation is a characteristic of many human cancers. HSP27 suppresses apoptosis and cytoskeletal reorganization. As a result, it is recognized as a critical therapeutic target for effective cancer therapy. Despite the effectiveness of multiple HSP27 inhibitors in pre-clinical investigations and clinical trials, no HSP27 inhibitor has progressed to the anticancer phase of the development. These difficulties have mostly been attributable to existing anticancer therapies’ inability to target oncogenic HSP27. Highly selective HSP27 inhibitors with higher effective-ness and low toxicity led to the development of combination techniques that include computer-aided assisted therapeutic discovery and design. This study emphasizes the most recent results and roles of HSP27 in cancer and the potential for utilizing an anticancer chemical database to uncover novel compounds to inhibit HSP27.

Mangiferin prevents hepatocyte epithelial-mesenchymal transition in liver fibrosis via targeting HSP27-mediated JAK2/STAT3 and TGF-β1/Smad pathway

Hepatocytes has been confirmed to undergo EMT and can be converted into myofibroblasts during hepatic fibrogenesis. However, the mechanism of hepatocyte EMT regulation in hepatic fibrosis, particularly through HSP27 (human homologue of rodent HSP25), remains unclear. Mangiferin (MAN), a compound extracted from Mangifera indica L, has been reported to attenuate liver injury. This study aimed to investigate the mechanisms underlying HSP27 inhibition and the anti-fibrotic effect of MAN in liver fibrosis. Our results revealed that the expression of HSP27 was remarkably increased in the liver tissues of patients with liver cirrhosis and CCl₄ -induced fibrotic rats. However, HSP27 shRNA treatment significantly alleviated fibrosis. Furthermore, MAN was found to inhibit CCl₄ - and TGF-β1-induced liver fibrosis and reduced hepatocyte EMT. More importantly, MAN decreased HSP27 expression to suppress the JAK2/STAT3 pathway, and subsequently blocked TGF-β1/Smad signaling, which were consistent with its protection against CCl₄ -induced EMT and liver fibrosis. Together, these results suggest that HSP27 may play a crucial role in hepatocyte EMT and liver fibrosis by activating JAK2/STAT3 signaling and TGF-β1/Smad pathway. The suppression of HSP27 expression by MAN may be a novel strategy for attenuating the hepatocyte EMT in liver fibrosis.

Construction and Validation of an Immune-Related Risk Score Model for Survival Prediction in Glioblastoma

Background

As one of the most important brain tumors, glioblastoma (GBM) has a poor prognosis, especially in adults. Immune-related genes (IRGs) and immune cell infiltration are responsible for the pathogenesis of GBM. This study aimed to identify new tumor markers to predict the prognosis of patients with GBM.

Methods

The Cancer Genome Atlas (TCGA) database and ImmPort database were used for model construction. The Wilcoxon rank-sum test was applied to identify the differentially expressed IRGs (DEIRGs) between the GBM and normal samples. Univariate Cox regression analysis and Kaplan–Meier analysis was performed to investigate the relationship between each DEIRG and overall survival. Next, multivariate Cox regression analysis was exploited to further explore the prognostic potential of DEIRGs. A risk-score model was constructed based on the above results. The area under the curve (AUC) values were calculated to assess the effect of the model prediction. Furthermore, the Chinese Glioma Genome Atlas (CGGA) dataset was used for model validation. STRING database and functional enrichment analysis were used for exploring the gene interactions and the underlying functions and pathways. The CIBERSORT algorithm was used for correlation analysis of the marker genes and the tumor-infiltrating immune cells.

Results

There were 198 DEIRGs in GBM, including 153 upregulated genes and 45 downregulated genes. Seven marker genes (LYNX1, PRELID1P4, MMP9, TCF12, RGS14, RUNX1, and CCR2) were filtered out by sequential screening for DEIRGs. The regression coefficients (0.0410, 1.335, 0.005, −0.021, 0.123, 0.142, and −0.329) and expression data of the marker genes were used to construct the model. The AUC values for 1, 2, and 3 years were 0.744, 0.737, and 0.749 in the TCGA–GBM cohort and 0.612, 0.602, and 0.594 in the CGGA-GBM cohort, respectively, which indicated a high predictive power. The results of enrichment analysis revealed that these genes were enriched in the activation of T cell and cytokine receptor interaction pathways. The interaction network map demonstrated a close relationship between the marker genes MMP9 and CCR2. Infiltration analysis of the immune cells showed that dendritic cells (DCs) could identify GBM, while LYNX1, RUNX1, and CCR2 were significantly positively correlated with DCs expression.

Conclusion

This study analyzed the expression of IRGs in GBM and identified seven marker genes for the construction of an immune-related risk score model. These marker genes were found to be associated with DCs and were enriched in similar immune response pathways. These findings are likely to provide new insights for the immunotherapy of patients with GBM.

A sequence space search engine for computational protein design to modulate molecular functionality

De-novo protein design explores the untapped sequence space that is otherwise less discovered during the evolutionary process. This necessitates an efficient sequence space search engine for effective convergence in computational protein design. We propose a greedy simulated annealing-based Monte-Carlo parallel search algorithm for better sequence-structure compatibility probing in protein design. The guidance provided by the evolutionary profile, the greedy approach, and the cooling schedule adopted in the Monte Carlo simulation ensures sufficient exploration and exploitation of the search space leading to faster convergence. On evaluating the proposed algorithm, we find that a dataset of 76 target scaffolds report an average root-mean-square-deviation (RMSD) of 1.07 Å and an average TM-Score of 0.93 with the modeled designed protein sequences. High sequence recapitulation of 48.7% (59.4%) observed in the design sequences for all (hydrophobic) solvent-inaccessible residues again establish the goodness of the proposed algorithm. A high (93.4%) intra-group recapitulation of hydrophobic residues in the solvent-inaccessible region indicates that the proposed protein design algorithm preserves the core residues in the protein and provides alternative residue combinations in the solvent-accessible regions of the target protein. Furthermore, a COFACTOR-based protein functional analysis shows that the design sequences exhibit altered molecular functionality and introduce new molecular functions compared to the target scaffolds.Communicated by Ramaswamy H. Sarma.

Hypermethylation of the Promoter of miR-338-5p Mediates Aberrant Expression of ETS-1 and Is Correlated With Disease Severity Of Astrocytoma Patients

The pro-oncogene ETS-1 (E26 transformation-specific sequence 1) is a key regulator of the proliferation and invasion of cancer cells. The present work examined the correlation of the aberrant expression of ETS-1 with histological or clinical classification of astrocytoma: grade I (pilocytic astrocytoma), grade II (diffuse astrocytoma), grade III (anaplastic astrocytoma), and grade IV (glioblastoma multiforme). MicroRNA, miR-338-5p, was predicted by an online tool (miRDB) to potentially target the 3’ untranslated region of ETS-1; this was confirmed by multi-assays, including western blot experiments or the point mutation of the targeting sites of miR-338-5p in ETS-1’s 3’untralation region (3’UTR). The expression of miR-338-5p was negatively associated with that of ETS-1 in astrocytoma, and deficiency of miR-338-5p would mediate aberrant expression of ETS-1 in astrocytoma. Mechanistically, hypermethylation of miR-338-5p by DNA methyltransferase 1 (DNMT1) resulted in repression of miR-338-5p expression and the aberrant expression of ETS-1. Knockdown or deactivation of DNMT1 decreased the methylation rate of the miR-338-5p promoter, increased the expression of miR-338-5p, and repressed the expression of ETS-1 in astrocytoma cell lines U251 and U87. These results indicate that hypermethylation of the miR-338-5p promoter by DNMT1 mediates the aberrant expression of ETS-1 related to disease severity of patients with astrocytoma.

Modularity-based parallel protein design algorithm with an implementation using shared memory programming

Given a target protein structure, the prime objective of protein design is to find amino acid sequences that will fold/acquire to the given three-dimensional structure. The protein design problem belongs to the non-deterministic polynomial-time-hard class as sequence search space increases exponentially with protein length. To ensure better search space exploration and faster convergence, we propose a protein modularity-based parallel protein design algorithm. The modular architecture of the protein structure is exploited by considering an intermediate structural organization between secondary structure and domain defined as protein unit (PU). Here, we have incorporated a divide-and-conquer approach where a protein is split into PUs and each PU region is explored in a parallel fashion. It has been further analyzed that our shared memory implementation of modularity-based parallel sequence search leads to better search space exploration compared to the case of traditional full protein design. Sequence-based analysis on design sequences depicts an average of 39.7% sequence similarity on the benchmark data set. Structure-based comparison of the modeled structures of the design protein with the target structure exhibited an average root-mean-square deviation of 1.17 Å and an average template modeling score of 0.89. The selected modeled structures of the design protein sequences are validated using 100 ns molecular dynamics simulations where 80% of the proteins have shown better or similar stability to the respective target proteins. Our study informs that our modularity-based protein design algorithm can be extended to protein interaction design as well.

Therapeutic Potential of Selenium in Glioblastoma

Little progress has been made in the long-term management of malignant brain tumors, leaving patients with glioblastoma, unfortunately, with a fatal prognosis. Glioblastoma remains the most aggressive primary brain cancer in adults. Similar to other cancers, glioblastoma undergoes a cellular metabolic reprogramming to form an oxidative tumor microenvironment, thereby fostering proliferation, angiogenesis and tumor cell survival. Latest investigations revealed that micronutrients, such as selenium, may have positive effects in glioblastoma treatment, providing promising chances regarding the current limitations in surgical treatment and radiochemotherapy outcomes. Selenium is an essential micronutrient with anti-oxidative and anti-cancer properties. There is additional evidence of Se deficiency in patients suffering from brain malignancies, which increases its importance as a therapeutic option for glioblastoma therapy. It is well known that selenium, through selenoproteins, modulates metabolic pathways and regulates redox homeostasis. Therefore, selenium impacts on the interaction in the tumor microenvironment between tumor cells, tumor-associated cells and immune cells. In this review we take a closer look at the current knowledge about the potential of selenium on glioblastoma, by focusing on brain edema, glioma-related angiogenesis, and cells in tumor microenvironment such as glioma-associated microglia/macrophages.

OPALS: A New Osimertinib Adjunctive Treatment of Lung Adenocarcinoma or Glioblastoma Using Five Repurposed Drugs

Background: Pharmacological targeting aberrant activation of epidermal growth factor receptor tyrosine kinase signaling is an established approach to treating lung adenocarcinoma. Osimertinib is a tyrosine kinase approved and effective in treating lung adenocarcinomas that have one of several common activating mutations in epidermal growth factor receptor. The emergence of resistance to osimertinib after a year or two is the rule. We developed a five-drug adjuvant regimen designed to increase osimertinib’s growth inhibition and thereby delay the development of resistance. Areas of Uncertainty: Although the assembled preclinical data is strong, preclinical data and the following clinical trial results can be discrepant. The safety of OPALS drugs when used individually is excellent. We have no data from humans on their tolerability when used as an ensemble. That there is no data from the individual drugs to suspect problematic interaction does not exclude the possibility. Data Sources: All relevant PubMed.org articles on the OPALS drugs and corresponding pathophysiology of lung adenocarcinoma and glioblastoma were reviewed. Therapeutic Opinion: The five drugs of OPALS are in wide use in general medicine for non-oncology indications. OPALS uses the anti-protozoal drug pyrimethamine, the antihistamine cyproheptadine, the antibiotic azithromycin, the antihistamine loratadine, and the potassium sparing diuretic spironolactone. We show how these inexpensive and generically available drugs intersect with and inhibit lung adenocarcinoma growth drive. We also review data showing that both OPALS adjuvant drugs and osimertinib have data showing they may be active in suppressing glioblastoma growth.

Small interfering RNA (siRNA) to target genes and molecular pathways in glioblastoma therapy: Current status with an emphasis on delivery systems

Glioblastoma multiforme (GBM) is one of the worst brain tumors arising from glial cells, causing many deaths annually. Surgery, chemotherapy, radiotherapy and immunotherapy are used for GBM treatment. However, GBM is still an incurable disease, and new approaches are required for its successful treatment. Because mutations and amplifications occurring in several genes are responsible for the progression and aggressive behavior of GBM cells, genetic approaches are of great importance in its treatment. Small interfering RNA (siRNA) is a new emerging tool to silence the genes responsible for disease progression, particularly cancer. SiRNA can be used for GBM treatment by down-regulating genes such as VEGF, STAT3, ELTD1 or EGFR. Furthermore, the use of siRNA can promote the chemosensitivity of GBM cells. However, the efficiency of siRNA in GBM is limited via its degradation by enzymes, and its off-targeting effects. SiRNA-loaded carriers, especially nanovehicles that are ligand-functionalized by CXCR4 or angiopep-2, can be used for the protection and targeted delivery of siRNA. Nanostructures can provide a platform for co-delivery of siRNA plus anti-tumor drugs as another benefit. The prepared nanovehicles should be stable and biocompatible in order to be tested in human studies.

An Evolutionary Profile Guided Greedy Parallel Replica-Exchange Monte Carlo Search Algorithm for Rapid Convergence in Protein Design

Protein design, also known as the inverse protein folding problem, is the identification of a protein sequence that folds into a target protein structure. Protein design is proved as an NP-hard problem. While researchers are working on designing heuristics with an emphasis on new scoring functions, we propose a replica-exchange Monte Carlo (REMC) search algorithm that ensures faster convergence using a greedy strategy. Using biological insights, we construct an evolutionary profile to encode the amino acid variability in different positions of the target protein from its structural homologs. The evolutionary profile guides the REMC search, and the greedy approach confirms appreciable exploration and exploitation of the sequence-structure fitness surface. We allow termination of a simulation trajectory once stagnant situation is detected. A series of sequence and structure level validations establish the goodness of our design. On a benchmark dataset, our algorithm reports an average root-mean-square deviation of 1.21Å between the target and the design proteins when modeled with an existing protein folding software. Besides, our algorithm assures 6.16 times overall speedup. In Molecular Dynamics simulations, we observe that four out of selected five design proteins report better to comparable stability to the corresponding target proteins.

Increased Levels of Plasma Extracellular Heat-Shock Proteins 60 and 70 kDa Characterized Early-Onset Neonatal Sepsis

Background: Extracellular heat-shock proteins (eHsp) are highly conserved molecules that play an important role in inflammatory diseases and have been quantified in plasma from patients with infectious diseases, including sepsis. There is a constant search for dependable biochemical markers that, in combination with conventional methods, could deliver a prompt and reliable diagnosis of early-onset neonatal sepsis. Objective: We sought to assess the level of eHsp-27, eHsp-60, eHsp-70, and tumor necrosis factor-alpha (TNFα) in plasma of healthy neonates at term and infants with early-onset neonatal sepsis. Methods: This study included 34 newborns that were classified as healthy neonates at term (blood samples from the umbilical cord, n = 23) or infants with early-onset neonatal sepsis (blood samples obtained from umbilical artery by standard sterile procedures before starting a systemic antibiotic intervention, n = 11). All blood samples were centrifuged, and the plasma recovered to determine eHsp-27, eHsp-60, eHsp-70, and TNFα levels by ELISA. Results: Our results indicate that the level of eHsp-27 in healthy neonates at term was 0.045 ± 0.024 pg/ml. This value decreased 2.5-fold in infants with early-onset neonate sepsis (0.019 ± 0.006 pg/ml, p = 0.004). In contrast, the levels of eHsp-60 and eHsp-70 in healthy neonates at term were 13.69 ± 5.3 and 4.03 ± 2.6 pg/ml, respectively. These protein levels increased significantly 1.8- and 1.9-fold in the plasma of infants with early-onset neonatal sepsis (p ≤ 0.001). The level of TNFα in healthy neonates at term was 2.94 ± 0.46 pg/ml, with a 3.0-fold increase in infants with early-onset neonatal sepsis (8.96 ± 0.72 pm/ml, p ≤ 0.001). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of eHsp compared with that of C-reactive protein were 73.3, 60.0, 47.8, and 33.3%, respectively. Conclusion: This study demonstrated a consistent increase of eHsp-60 and eHsp-70 in the plasma of infants diagnosed with early-onset neonatal sepsis. These proteins showed higher sensitivity and specificity than C-reactive protein and blood culture test.

Progress in Natural Compounds/siRNA Co-delivery Employing Nanovehicles for Cancer Therapy

Chemotherapy using natural compounds, such as resveratrol, curcumin, paclitaxel, docetaxel, etoposide, doxorubicin, and camptothecin, is of importance in cancer therapy because of the outstanding therapeutic activity and multitargeting capability of these compounds. However, poor solubility and bioavailability of natural compounds have limited their efficacy in cancer therapy. To circumvent this hurdle, nanocarriers have been designed to improve the antitumor activity of the aforementioned compounds. Nevertheless, cancer treatment is still a challenge, demanding novel strategies. It is well-known that a combination of natural products and gene therapy is advantageous over monotherapy. Delivery of multiple therapeutic agents/small interfering RNA (siRNA) as a potent gene-editing tool in cancer therapy can maximize the synergistic effects against tumor cells. In the present review, co-delivery of natural compounds/siRNA using nanovehicles are highlighted to provide a backdrop for future research.

Insight into Cisplatin-Resistance Signaling of W1 Ovarian Cancer Cells Emerges mTOR and HSP27 as Targets for Sensitization Strategies

The microenvironment possesses a strong impact on the tumor chemoresistance when cells bind to components of the extracellular matrix. Here we elucidate the signaling pathways of cisplatin resistance in W1 ovarian cancer cells binding to collagen type 1 (COL1) and signaling interference with constitutive cisplatin resistance in W1CR cells to discover the targets for sensitization. Proteome kinase arrays and Western blots were used to identify the signaling components, their impact on cisplatin resistance was evaluated by inhibitory or knockdown approaches. W1 cell binding to COL1 upregulates integrin-associated signals via FAK/PRAS40/mTOR, confirmed by β1-integrin (ITGB1) knockdown. mTOR appears as key for resistance, its blockade reversed COL1 effects on W1 cell resistance completely. W1CR cells compensate ITGB1-knockdown by upregulation of discoidin domain receptor 1 (DDR1) as alternative COL1 sensor. COL1 binding via DDR1 activates the MAPK pathway, of which JNK1/2 appears critical for COL1-mediated resistance. JNK1/2 inhibition inverts COL1 effects in W1CR cells, whereas intrinsic cisplatin resistance remained unaffected. Remarkably, knockdown of HSP27, another downstream MAPK pathway component overcomes intrinsic resistance completely sensitizing W1CR cells to the level of W1 cells for cisplatin cytotoxicity. Our data confirm the independent regulation of matrix-induced and intrinsic chemoresistance in W1 ovarian cancer cells and offer novel targets for sensitization.

Ebola Virus VP35 Protein: Modeling of the Tetrameric Structure and an Analysis of Its Interaction with Human PKR

The Viral Protein 35 (VP35), a crucial protein of the Zaire Ebolavirus (EBOV), interacts with a plethora of human proteins to cripple the human immune system. Despite its importance, the entire structure of the tetrameric assembly of EBOV VP35 and the means by which it antagonizes the autophosphorylation of the kinase domain of human protein kinase R (PKRK) is still elusive. We consult existing structural information to model a tetrameric assembly of the VP35 protein where 93% of the protein is modeled using crystal structure templates. We analyze our modeled tetrameric structure to identify interchain bonding networks and use molecular dynamics simulations and normal-mode analysis to unravel the flexibility and deformability of the different regions of the VP35 protein. We establish that the C-terminal of VP35 (VP35C) directly interacts with PKRK to prevent it from autophosphorylation. Further, we identify three plausible VP35C-PKRK complexes with better affinity than the PKRK dimer formed during autophosphorylation and use protein design to establish a new stretch in VP35C that interacts with PKRK. The proposed tetrameric assembly will aid in better understanding of the VP35 protein, and the reported VP35C-PKRK complexes along with their interacting sites will help in the shortlisting of small molecule inhibitors.

The matrix metalloproteinase 7 (MMP7) links Hsp90 chaperone with acquired drug resistance and tumor metastasis

BACKGROUND

Cancer emergence is associated with a series of cellular transformations that include acquired drug resistance followed by tumor metastasis. Matrix metalloproteinases (MMPs) and Hsp90 chaperone are implicated in tumor progression, however, they are not studied in the context of drug resistance.

AIMS

In the present study, we aimed at understanding the cross-talk between acquired drug resistance and tumor progression, linking MMP7 and Hsp90.

METHODS AND RESULTS

We have developed an in vitro model system for acquired drug resistance and studied the correlation between MMP7 and Hsp90. We demonstrate that enhanced drug efflux activity correlates with the induced expression and activity of MMP7, and enhanced metastatic potential of cells, however, in Hsp90-dependent manner. The MMP7 overexpression alone could enhance the drug efflux activity marginally, and metastasis significantly. However, challenging these cells with 17AAG has significantly increased the drug efflux activity and, in contrast, decreased the metastatic potential. Evaluating our in vitro findings in mice xenografts revealed that MMP7 overexpression facilitates altered homing properties. However, these cells, in response to 17AAG treatment, exhibited increased localized tumor growth but decreased tumor metastasis.

CONCLUSION

We demonstrated a cross-talk between Hsp90 and MMP7 in regulating the acquired drug resistance and tumor progression. Our findings provide novel insights on targeting drug resistant-tumors.

Antiangiogenic Targets for Glioblastoma Therapy from a Pre-Clinical Approach, Using Nanoformulations

Glioblastoma (GBM) is the most aggressive tumor type whose resistance to conventional treatment is mediated, in part, by the angiogenic process. New treatments involving the application of nanoformulations composed of encapsulated drugs coupled to peptide motifs that direct drugs to specific targets triggered in angiogenesis have been developed to reach and modulate different phases of this process. We performed a systematic review with the search criterion (Glioblastoma OR Glioma) AND (Therapy OR Therapeutic) AND (Nanoparticle) AND (Antiangiogenic OR Angiogenesis OR Anti-angiogenic) in Pubmed, Scopus, and Cochrane databases, in which 312 articles were identified; of these, only 27 articles were included after selection and analysis of eligibility according to the inclusion and exclusion criteria. The data of the articles were analyzed in five contexts: the characteristics of the tumor cells; the animal models used to induce GBM for antiangiogenic treatment; the composition of nanoformulations and their physical and chemical characteristics; the therapeutic anti-angiogenic process; and methods for assessing the effects on antiangiogenic markers caused by therapies. The articles included in the review were heterogeneous and varied in practically all aspects related to nanoformulations and models. However, there was slight variance in the antiangiogenic effect analysis. CD31 was extensively used as a marker, which does not provide a view of the effects on the most diverse aspects involved in angiogenesis. Therefore, the present review highlighted the need for standardization between the different approaches of antiangiogenic therapy for the GBM model that allows a more effective meta-analysis and that helps in future translational studies.

Lumefantrine, an antimalarial drug, reverses radiation and temozolomide resistance in glioblastoma

Glioblastoma multiforme (GBM) is an aggressive cancer without currently effective therapies. Radiation and temozolomide (radio/TMZ) resistance are major contributors to cancer recurrence and failed GBM therapy. Heat shock proteins (HSPs), through regulation of extracellular matrix (ECM) remodeling and epithelial mesenchymal transition (EMT), provide mechanistic pathways contributing to the development of GBM and radio/TMZ-resistant GBM. The Friend leukemia integration 1 (Fli-1) signaling network has been implicated in oncogenesis in GBM, making it an appealing target for advancing novel therapeutics. Fli-1 is linked to oncogenic transformation with up-regulation in radio/TMZ-resistant GBM, transcriptionally regulating HSPB1. This link led us to search for targeted molecules that inhibit Fli-1. Expression screening for Fli-1 inhibitors identified lumefantrine, an antimalarial drug, as a probable Fli-1 inhibitor. Docking and isothermal calorimetry titration confirmed interaction between lumefantrine and Fli-1. Lumefantrine promoted growth suppression and apoptosis in vitro in parental and radio/TMZ-resistant GBM and inhibited tumor growth without toxicity in vivo in U87MG GBM and radio/TMZ-resistant GBM orthotopic tumor models. These data reveal that lumefantrine, an FDA-approved drug, represents a potential GBM therapeutic that functions through inhibition of the Fli-1/HSPB1/EMT/ECM remodeling protein networks.

Molecular Chaperones in Cancer Stem Cells: Determinants of Stemness and Potential Targets for Antitumor Therapy

Cancer stem cells (CSCs) are a great challenge in the fight against cancer because these self-renewing tumorigenic cell fractions are thought to be responsible for metastasis dissemination and cases of tumor recurrence. In comparison with non-stem cancer cells, CSCs are known to be more resistant to chemotherapy, radiotherapy, and immunotherapy. Elucidation of mechanisms and factors that promote the emergence and existence of CSCs and their high resistance to cytotoxic treatments would help to develop effective CSC-targeting therapeutics. The present review is dedicated to the implication of molecular chaperones (protein regulators of polypeptide chain folding) in both the formation/maintenance of the CSC phenotype and cytoprotective machinery allowing CSCs to survive after drug or radiation exposure and evade immune attack. The major cellular chaperones, namely heat shock proteins (HSP90, HSP70, HSP40, HSP27), glucose-regulated proteins (GRP94, GRP78, GRP75), tumor necrosis factor receptor-associated protein 1 (TRAP1), peptidyl-prolyl isomerases, protein disulfide isomerases, calreticulin, and also a transcription heat shock factor 1 (HSF1) initiating HSP gene expression are here considered as determinants of the cancer cell stemness and potential targets for a therapeutic attack on CSCs. Various approaches and agents are discussed that may be used for inhibiting the chaperone-dependent development/manifestations of cancer cell stemness.

Transcriptional regulation of HSPB1 by Friend leukemia integration-1 factor modulates radiation and temozolomide resistance in glioblastoma

Glioblastoma (GBM) is the most common primary brain tumor and is invariably fatal. Heat shock proteins (HSPs) provide protein signatures/biomarkers for GBM that afford potential as targets for developing anti-GBM drugs. In GBM, elevated expression of hypoxia inducible factors under the influence of Ets family proteins significantly promotes the expression of HSPs. RNAseq analysis identified HSPB1 as a prominent upregulated HSP in GBM and in radiation resistant/temozolomide resistant (radio/TMZR) GBM. Here, we established friend leukemia integration 1 (Fli-1), a member of Ets family to be playing a transcriptional regulatory role on the HSPB1 gene. Fli-1 binds to nucleotide residues GGAA at binding sites 3, 6 and 7 in the 5-kb upstream region of HSPB1. Fli-1 has been linked to oncogenic transformation with upregulation in radio/TMZR GBM. Overexpression of Fli-1 in GBM promotes resistance, whereas Fli-1 knockdown in radio/TMZR GBM cells suppresses resistance. We identify the underlying molecular mechanisms of Fli-1-mediated regulation of HSPB1 that drive extracellular matrix remodeling and epithelial to mesenchymal transition in radio/TMZR GBM cells. This study uncovers Fli-1 as a potential therapeutic target for combating radiation and temozolomide resistance in GBM.

Current and Future Trends on Diagnosis and Prognosis of Glioblastoma: From Molecular Biology to Proteomics

Glioblastoma multiforme is the most aggressive malignant tumor of the central nervous system. Due to the absence of effective pharmacological and surgical treatments, the identification of early diagnostic and prognostic biomarkers is of key importance to improve the survival rate of patients and to develop new personalized treatments. On these bases, the aim of this review article is to summarize the current knowledge regarding the application of molecular biology and proteomics techniques for the identification of novel biomarkers through the analysis of different biological samples obtained from glioblastoma patients, including DNA, microRNAs, proteins, small molecules, circulating tumor cells, extracellular vesicles, etc. Both benefits and pitfalls of molecular biology and proteomics analyses are discussed, including the different mass spectrometry-based analytical techniques, highlighting how these investigation strategies are powerful tools to study the biology of glioblastoma, as well as to develop advanced methods for the management of this pathology.