mTOR inhibitors in urinary bladder cancer

Exploring the Targets and Molecular Mechanisms of Curcumin for the Treatment of Bladder Cancer Based on Network Pharmacology, Molecular Docking and Molecular Dynamics

Curcumin, a phenolic compound derived from turmeric, has demonstrated anti-tumor properties in preclinical models of various cancers. However, the exact mechanism of curcumin in treating bladder cancer remains unclear. This study aimed to elucidate the therapeutic targets and molecular mechanisms of curcumin in the treatment of BC through an integrated approach of network pharmacology, molecular docking, and molecular dynamics simulations. PharmMapper, SuperPred, TargetNet, and SwissTargetPrediction were utilized to acquire targets associated with curcumin, while GeneCards, CTD, DisGeNET, OMIM, and PharmGKB databases were utilized to obtain targets related to bladder cancer. The drug-disease interaction targets were obtained using Venny 2.1.0, and GO and KEGG enrichment analyses were then conducted with the DAVID tool. We constructed a protein-protein interaction (PPI) network and identified tenkey targets. In conclusion, AutoDock Tools 1.5.7 was utilized to conduct molecular docking simulations, followed by additional analysis of the central targets through the GEPIA, HPA, cBioPortal, and TIMER databases. A total of 305 potential anticancer targets of curcumin were obtained. The analysis of GO functional enrichment resulted in a total of 1105 terms, including 786 terms related to biological processes (BP), 105 terms related to cellular components (CC), and 214 terms related to molecular functions (MF). In addition, KEGG pathway enrichment analysis identified 170 relevant signaling pathways. Treating bladder cancer could potentially involve inhibiting pathways like the PI3K-Akt signaling pathway, MAPK signaling pathway, EGFR tyrosine kinase inhibitor resistance, and IL-17 signaling pathway. Activating TNF, ALB, CASP3, and ESR1 while inhibiting AKT1, EGFR, STAT3, BCL2, SRC, and HSP90AA1 can also hinder the proliferation of bladder tumor cells. According to the results of molecular docking, curcumin binds to these central targets in a spontaneous manner, exhibiting binding energies lower than - 1.631 kJ/mol. These findings were further validated at the transcriptional, translational and immune infiltration levels. By utilizing network pharmacology and molecular docking techniques, it was discovered that curcumin possesses diverse effects on multiple targets and pathways for treating bladder cancer. It has the potential to impede the growth of bladder tumor cells by suppressing various pathways including the PI3K-Akt and MAPK signaling pathways, as well as pathways associated with EGFR tyrosine kinase inhibitor resistance and the IL-17 signaling pathway. Curcumin could potentially disrupt the cell cycle advancement in bladder cancer cells by increasing the expression of TNF, ALB, CASP3, and ESR1 while decreasing AKT1, EGFR, STAT3, BCL2, SRC, HSP90AA1, and other targeted genes. These findings reveal the possible molecular pathways through which curcumin exerts its anticancer effects in bladder cancer, and this novel research strategy not only provides an important basis for an in-depth understanding of the anticancer mechanism of curcumin, but also offers new potential drugs and targets for the clinical treatment of bladder cancer. Therefore, this study is of great scientific significance and practical application value for promoting the development of bladder cancer therapeutic field. This finding provides strong support for the development of novel, safe and effective drugs for bladder cancer treatment.

The complex interplay between redox dysregulation and mTOR signaling pathway in cancer: A rationale for cancer treatment

The mechanistic target of rapamycin (mTOR) is a highly conserved serine/threonine kinase that plays a critical role in regulating cellular processes such as growth, proliferation, and metabolism in healthy cells. Dysregulation of mTOR signaling and oxidative stress have been implicated in various diseases including cancer. This review aims to provide an overview of the current understanding of mTOR and its involvement in cell survival and the regulation of cancer cell metabolism as well as its complex interplay with reactive oxygen species (ROS). On the one hand, ROS can inhibit or activate mTOR pathway in cancer cells through various mechanisms. Conversely, mTOR signaling can induce oxidative stress in tumor cells notably due to the inhibition in the expression of antioxidant enzyme genes. Since mTOR is often activated and plays crucial role in cancer cell survival, the use of mTOR inhibitors, which often induce ROS accumulation, could be an interesting approach for cancer treatment. This review will address the advantages, disadvantages, combination strategies, and limitations associated with therapeutic modulation of mTOR signaling pathway in cancer treatment.

Prevention and Treatment of Side Effects of Immunotherapy for Bladder Cancer

Bladder cancer (BC) is one of the most important tumors of the genitourinary system, associated with high morbidity and mortality rates. Over the years, various antitumor treatments have been developed, and immunotherapy is one of the most effective methods. Immunotherapy aims to activate the body’s immune system to kill cancer cells. It has been established that immunotherapy drugs can be classified into “non-targeted” and “targeted” drugs depending on their site of action. Immunotherapy is reportedly effective for BC. Even though it can attack cancer cells, it can also cause the immune system to attack healthy cells, which can occur at any time during treatment and sometimes even after immunotherapy is stopped. Importantly, different types of immunotherapies can cause different side effects. Side effects may manifest themselves as signs or as symptoms. The prevention and treatment of side effects caused by immunotherapy is an important part of cancer patient management.

New Perspectives in the Medical Treatment of Non-Muscle-Invasive Bladder Cancer: Immune Checkpoint Inhibitors and Beyond

Non-muscle-invasive bladder cancer (NMIBC) is characterized by a high rate of cure, but also by a non-negligible probability of recurrence and risk progression to muscle-invasive disease. NMIBC management requires a proper local resection and staging, followed by a risk-based treatment with intravesical agents. For many years, the current gold standard treatment for patients with intermediate or high-risk disease is transurethral resection of the bladder (TURB) followed by intravesical bacillus Calmette-Guérin (BCG) instillations. Unfortunately, in about half of high-risk patients, intravesical BCG treatment fails and NMIBC persists or recurs early. While radical cystectomy remains the gold standard for these patients, new therapeutic targets are being individuated and studied. Radical cystectomy in fact can provide an excellent long-term disease control, but can deeply interfere with quality of life. In particular, the enhanced immune checkpoints expression shown in BCG-unresponsive patients and the activity of immune checkpoints inhibitors (ICIs) in advanced bladder cancer provided the rationale for testing ICIs in NMIBC. Recently, pembrolizumab has shown promising activity in BCG-unresponsive NMIBC patients, obtaining FDA approval. Meanwhile multiple novel drugs with alternative mechanisms of action have proven to be safe and effective in NMIBC treatment and others are under investigation. The aim of this review is to analyse and describe the clinical activity of new emerging drugs in BCG-unresponsive NMIBC focusing on immunotherapy results.

Bladder Cancer-related microRNAs With In Vivo Efficacy in Preclinical Models

Progressive and metastatic bladder cancer remain difficult to treat. In this review, we critique seven up-regulated and 25 down-regulated microRNAs in order to identify new therapeutic entities and corresponding targets. These microRNAs were selected with respect to their efficacy in bladder cancer-related preclinical in vivo models. MicroRNAs and related targets interfering with chemoresistance, cell-cycle, signaling, apoptosis, autophagy, transcription factor modulation, epigenetic modification and metabolism are described. In addition, we highlight microRNAs targeting transmembrane receptors and secreted factors. We discuss druggability issues for the identified targets.

Anti-Cancer Effects of Zotarolimus Combined with 5-Fluorouracil Treatment in HCT-116 Colorectal Cancer-Bearing BALB/c Nude Mice

Zotarolimus is a semi-synthetic derivative of rapamycin and an inhibitor of mammalian target of rapamycin (mTOR) signaling. Currently, zotarolimus is used to prolong the survival time of organ grafts, but it is also a novel immunosuppressive agent with potent anti-proliferative activity. Here, we examine the anti-tumor effect of zotarolimus, alone and in combination with 5-fluorouracil, on HCT-116 colorectal adenocarcinoma cells implanted in BALB/c nude mice. Compared with the control mice, mice treated with zotarolimus or zotarolimus combined with 5-FU showed retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; reduced inflammation-related factors such as IL-1β, TNF-α, and cyclooxygenase-2 (COX-2) protein; and inhibited metastasis-related factors such as CD44, epidermal growth factor receptor (EGFR), transforming growth factor β (TGF-β), and vascular endothelial growth factor (VEGF). Notably, mice treated with a combination of zotarolimus and 5-FU showed significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with mice treated with 5-FU or zotarolimus alone, indicating a strong synergistic effect. This in vivo study confirms that zotarolimus or zotarolimus combined with 5-FU can be used to retard colorectal adenocarcinoma growth and inhibit tumorigenesis. Our results suggest that zotarolimus may increase the chemo-sensitization of tumor cells. Therefore, zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents in the treatment of human colon adenocarcinoma. Future research on zotarolimus may lead to the development of new therapeutic strategies.

Anti-tumor effect of trametinib in bladder cancer organoid and the underlying mechanism

Bladder cancer (BC), a main neoplasm of urinary tract, is usually inoperable and unresponsive to chemotherapy. As a novel experimental model for muscle-invasive BC, we previously established a culture method of dog BC organoids. In the present study, the detailed in vitro and in vivo anti-tumor effects of trametinib were investigated by using this model. In each BC organoid strain, epidermal growth factor receptor (EGFR)/ERK signaling was upregulated compared with normal bladder cells. Trametinib even at a low concentration inhibited the cell viability of BC organoids and the activation of ERK through decreasing expression of c-Myc, ELK1, SIK1, and PLA2G4A. Trametinib arrested cell cycle of BC with few apoptosis. Dual treatment of BC organoids with trametinib and YAP inhibitor, verteporfin extremely inhibited the cell viability with apoptosis induction. Moreover, trametinib induced basal to luminal differentiation of BC organoids by upregulating luminal markers and downregulating basal ones. In vivo, trametinib decreased the tumor growth of BC organoids in mice and the xenograft-derived organoids from trametinib-administered mice showed enhanced sensitivity to carboplatin due to MSH2 upregulation. Our data suggested a new strategy of trametinib-YAP inhibitor or trametinib-carboplatin combination as a promising treatment of BC.

A network pharmacology perspective for deciphering potential mechanisms of action of Solanum nigrum L. in bladder cancer

BACKGROUND

Solanum nigrum L. decoction has been used as a folklore medicine in China to prevent the postoperative recurrence of bladder cancer (BC). However, there are no previous pharmacological studies on the protective mechanisms of this activity of the plant. Thus, this study aimed to perform a systematic analysis and to predict the potential action mechanisms underlying S. nigrum activity in BC based on network pharmacology.

METHODS

Based on network pharmacology, the active ingredients of S. nigrum and the corresponding targets were identified using the Traditional Chinese Medicines for Systems Pharmacology Database and Analysis Platform database, and BC-related genes were screened using GeneCards and the Online Mendelian Inheritance in Man database. In addition, ingredient-target (I-T) and protein-protein interaction (PPI) networks were constructed using STRING and Cytoscape, Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted, and then the pathways directly related to BC were integrated manually to reveal the pharmacological mechanism underlying S. nigrum-medicated therapeutic effects in BC.

RESULTS

Seven active herbal ingredients from 39 components of S. nigrum were identified, which shared 77 common target genes related to BC. I-T network analysis revealed that quercetin was associated with all targets and that NCOA2 was targeted by four ingredients. Besides, interleukin 6 had the highest degree value in the PPI network, indicating a hub role. A subsequent gene enrichment analysis yielded 86 significant GO terms and 89 significant pathways, implying that S. nigrum had therapeutic benefits in BC through multi-pathway effects, including the HIF-1, TNF, P53, MAPK, PI3K/Akt, apoptosis and bladder cancer pathway.

CONCLUSIONS

S. nigrum may mediate pharmacological effects in BC through multi-target and various signaling pathways. Further validation is required experimentally. Network pharmacology approach provides a predicative novel strategy to reveal the holistic mechanism of action of herbs.

MiR-101 reduces cell proliferation and invasion and enhances apoptosis in endometrial cancer via regulating PI3K/Akt/mTOR

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Prognostic factors of non-muscle invasive bladder cancer: a study based on next-generation sequencing

Objective

To investigate the genetic prognostic factors for the recurrence of non-muscle invasive bladder cancer.

Materials and methods

The patients underwent transurethral resection of bladder tumor and received bacillus Calmette–Guérin (BCG) or epirubicin. Next-generation sequencing was performed and alterations of genes, pathways, and tumor mutation burden were recorded. Associations between these clinicopathological and genetic variants were estimated, and prognostic factor identified.

Results

A total of 58 cases were included in our study, and 46 patients underwent treatment with BCG. FGFR3 was the most frequently altered gene (48%), and more commonly detected in intermediate-risk patients. Univariate Cox analysis demonstrated that 10 genes were significantly correlated with BCG failure, while NEB, FGFR1 and SDHC were independent recurrence predictors. Besides, epigenetic-related gene pathway mutations were negatively correlated with recurrence (hazard ratio: 0.198, P = 0.023). DNA damage response and repair gene alterations were positively correlated with tumor burden, while altered TP53 was most frequent among these genes and significant correlated with high tumor burden.

Conclusion

BCG instillation significantly reduced the rate of recurrence compared with epirubicin in this population. Potential biomarkers and therapeutic targets were found with the help of next-generation sequencing; correlations between DDR genes alterations and high tumor mutation burden were also demonstrated.

Immunotherapy in Bladder Cancer: Current Methods and Future Perspectives

Bladder cancer is one of the most significant genitourinary cancer, causing high morbidity and mortality in a great number of patients. Over the years, various treatment methods for this type of cancer have been developed. The most common is the highly efficient method using Bacillus Calmette-Guerin, giving a successful effect in a high percentage of patients. However, due to the genetic instability of bladder cancer, together with individual needs of patients, the search for different therapy methods is ongoing. Immune checkpoints are cell surface molecules influencing the immune response and decreasing the strength of the immune response. Among those checkpoints, the PD-1 (programmed cell death protein-1)/PD-L1 (programmed cell death protein ligand 1) inhibitors aim at blocking those molecules, which results in T cell activation, and in bladder cancer the use of Atezolizumab, Avelumab, Durvalumab, Nivolumab, and Pembrolizumab has been described. The inhibition of another pivotal immune checkpoint, CTLA-4 (cytotoxic T cell antigen), may result in the mobilization of the immune system against bladder cancer and, among anti-CTLA-4 antibodies, the use of Ipilimumab and Tremelimumab has been discussed. Moreover, several different approaches to successful bladder cancer treatment exists, such as the use of ganciclovir and mTOR (mammalian target of rapamycin) kinase inhibitors, IL-12 (interleukin-12) and COX-2 (cyclooxygenase-2). The use of gene therapies and the disruption of different signaling pathways are currently being investigated. Research suggests that the combination of several methods increases treatment efficiency and the positive outcome in individual.

Simultaneous inhibition of atypical protein kinase‑C and mTOR impedes bladder cancer cell progression

Despite enormous scientific advancements in cancer treatment, there is a need for research to combat cancer, particularly bladder cancer. Drugs once proved to be effective in treating bladder cancer have shown reduced efficacy; hence, the cancer recurrence rate is increasing. To overcome this situation, several strategies have been considered, including the development of novel active drugs or modification of existing therapeutic regimens by combining two or more existing drugs. In recent years, atypical protein kinase Cs (PKCs), phospholipid-dependent serine/threonine kinases, have been considered as a central regulator of various cancer-associated signaling pathways, and they control cell cycle progression, tumorigenesis and metastasis. Additionally, the biologically crucial mTOR signaling pathway is altered in numerous types of cancer, including bladder cancer. Furthermore, despite independent activation, atypical PKC signaling can be triggered by mTOR. The present study examined whether the concurrent inhibition of atypical PKCs and mTOR using a combination of novel atypical PKC inhibitors (ICA-I, an inhibitor of PKC-ι; or ζ-Stat, an inhibitor of PKC-ζ) and rapamycin blocks bladder cancer progression. In the present study, healthy bladder MC-SV-HUCT2 and bladder cancer TCCSUP cells were tested and subjected to a WST1 assay, western blot analysis, immunoprecipitation, a scratch wound healing assay, flow cytometry and immunofluorescence analyses. The results revealed that the combination therapy induced a reduction in human bladder cancer cell viability compared with control and individual atypical PKC inhibitor and rapamycin treatment. Additionally, the concurrent inhibition of atypical PKCs and mTOR retards the migration of bladder cancer cells. These findings indicated that the administration of atypical PKC inhibitors together with rapamycin could be a useful therapeutic option in treating bladder cancer.

Mechanisms behind Temsirolimus Resistance Causing Reactivated Growth and Invasive Behavior of Bladder Cancer Cells In Vitro

Background: Although mechanistic target of rapamycin (mTOR) inhibitors, such as temsirolimus, show promise in treating bladder cancer, acquired resistance often hampers efficacy. This study evaluates mechanisms leading to resistance. Methods: Cell growth, proliferation, cell cycle phases, and cell cycle regulating proteins were compared in temsirolimus resistant (res) and sensitive (parental—par) RT112 and UMUC3 bladder cancer cells. To evaluate invasive behavior, adhesion to vascular endothelium or to immobilized extracellular matrix proteins and chemotactic activity were examined. Integrin α and β subtypes were analyzed and blocking was done to evaluate physiologic integrin relevance. Results: Growth of RT112res could no longer be restrained by temsirolimus and was even enhanced in UMUC3res, accompanied by accumulation in the S- and G2/M-phase. Proteins of the cdk-cyclin and Akt-mTOR axis increased, whereas p19, p27, p53, and p73 decreased in resistant cells treated with low-dosed temsirolimus. Chemotactic activity of RT112res/UMUC3res was elevated following temsirolimus re-exposure, along with significant integrin α2, α3, and β1 alterations. Blocking revealed a functional switch of the integrins, driving the resistant cells from being adhesive to being highly motile. Conclusion: Temsirolimus resistance is associated with reactivation of bladder cancer growth and invasive behavior. The α2, α3, and β1 integrins could be attractive treatment targets to hinder temsirolimus resistance.

mTOR Signaling Pathway in Cancer Targets Photodynamic Therapy In Vitro

The Mechanistic or Mammalian Target of Rapamycin (mTOR) is a major signaling pathway in eukaryotic cells belonging to the P13K-related kinase family of the serine/threonine protein kinase. It has been established that mTOR plays a central role in cellular processes and implicated in various cancers, diabetes, and in the aging process with very poor prognosis. Inhibition of the mTOR pathway in the cells may improve the therapeutic index in cancer treatment. Photodynamic therapy (PDT) has been established to selectively eradicate neoplasia at clearly delineated malignant lesions. This review highlights recent advances in understanding the role or regulation of mTOR in cancer therapy. It also discusses how mTOR currently contributes to cancer as well as future perspectives on targeting mTOR therapeutically in cancer in vitro.

mTOR Signaling in Cancer and mTOR Inhibitors in Solid Tumor Targeting Therapy

The mammalian or mechanistic target of rapamycin (mTOR) pathway plays a crucial role in regulation of cell survival, metabolism, growth and protein synthesis in response to upstream signals in both normal physiological and pathological conditions, especially in cancer. Aberrant mTOR signaling resulting from genetic alterations from different levels of the signal cascade is commonly observed in various types of cancers. Upon hyperactivation, mTOR signaling promotes cell proliferation and metabolism that contribute to tumor initiation and progression. In addition, mTOR also negatively regulates autophagy via different ways. We discuss mTOR signaling and its key upstream and downstream factors, the specific genetic changes in the mTOR pathway and the inhibitors of mTOR applied as therapeutic strategies in eight solid tumors. Although monotherapy and combination therapy with mTOR inhibitors have been extensively applied in preclinical and clinical trials in various cancer types, innovative therapies with better efficacy and less drug resistance are still in great need, and new biomarkers and deep sequencing technologies will facilitate these mTOR targeting drugs benefit the cancer patients in personalized therapy.

HDAC Inhibition Counteracts Metastatic Re-Activation of Prostate Cancer Cells Induced by Chronic mTOR Suppression

This study was designed to investigate whether epigenetic modulation by histone deacetylase (HDAC) inhibition might circumvent resistance towards the mechanistic target of rapamycin (mTOR) inhibitor temsirolimus in a prostate cancer cell model. Parental (par) and temsirolimus-resistant (res) PC3 prostate cancer cells were exposed to the HDAC inhibitor valproic acid (VPA), and tumor cell adhesion, chemotaxis, migration, and invasion were evaluated. Temsirolimus resistance was characterized by reduced binding of PC3^res cells to endothelium, immobilized collagen, and fibronectin, but increased adhesion to laminin, as compared to the parental cells. Chemotaxis, migration, and invasion of PC3^res cells were enhanced following temsirolimus re-treatment. Integrin α and β receptors were significantly altered in PC3^res compared to PC3^par cells. VPA significantly counteracted temsirolimus resistance by down-regulating tumor cell–matrix interaction, chemotaxis, and migration. Evaluation of integrin expression in the presence of VPA revealed a significant down-regulation of integrin α5 in PC3^res cells. Blocking studies demonstrated a close association between α5 expression on PC3^res and chemotaxis. In this in vitro model, temsirolimus resistance drove prostate cancer cells to become highly motile, while HDAC inhibition reversed the metastatic activity. The VPA-induced inhibition of metastatic activity was accompanied by a lowered integrin α5 surface level on the tumor cells.

Treatment of melanoma with selected inhibitors of signaling kinases effectively reduces proliferation and induces expression of cell cycle inhibitors

Cancer treatment often tends to involve direct targeting enzymes essential for the growth and proliferation of cancer cells. The aim of this study was the recognition of the possible role of selected protein kinases: PI3K, ERK1/2, and mTOR in cell proliferation and cell cycle in malignant melanoma. We investigated the role of protein kinase inhibitors: U0126 (ERK1/2), LY294002 (PI3K), rapamycin (mTOR), everolimus (mTOR), GDC-0879 (B-RAF), and CHIR-99021 (GSK3beta) in cell proliferation and expression of crucial regulatory cell cycle proteins in human melanoma cells: WM793 (VGP) and Lu1205 (metastatic). They were used either individually or in various combinations. The study on the effect of signaling kinases inhibitors on proliferation—BrdU ELISA test after 48–72 h. Their effect on the expression of cell cycle regulatory proteins: cyclin D1 and D3, cyclin-dependent kinase CDK4 and CDK6, and cell cycle inhibitors: p16, p21, and p27, was studied at the protein level (western blot). Treatment of melanoma cells with protein kinase inhibitors led to significantly decreased cell proliferation except the use of a GSK-3β kinase inhibitors—CHIR-99021. The significant decrease in the expression of selected cyclins and cyclin-dependent kinases (CDKs) with parallel increase in the expression of some of cyclin-dependent kinases inhibitors and in consequence meaningful reduction in melanoma cell proliferation by the combinations of inhibitors of signaling kinases clearly showed the crucial role of AKT, ERK 1/2, and mTOR signal transduction in melanoma progression. The results unanimously indicate those pathways as an important target for treatment of melanoma.

Intravesical Immunomodulatory Imiquimod Enhances Bacillus Calmette-Guérin Downregulation of Nonmuscle-invasive Bladder Cancer

BACKGROUND

The Toll-like receptor (TLR)2/4 agonist bacillus Calmette-Guérin (BCG), although not failure proof, has been the most efficient immunomodulatory treatment of immunogenic nonmuscle-invasive bladder cancer (NMIBC) for > 40 years. We investigated the role of the immunomodulatory molecule TLR7 agonist imiquimod through the BCG key receptors TLR2/4 and the main downstream molecules of the mammalian target of rapamycin pathway in NMIBC treatment.

MATERIALS AND METHODS

A total of 40 Fischer-344 rats, 7 weeks old, received 4 doses of 1.5 mg/kg N-methyl-N-nitrosourea intravesically on weeks 0, 2, 4, and 6 for cancer induction. At week 8, the rats were randomized into 4 groups (10 per group) and treated intravesically once a week for 6 weeks: control (0.2 mL of vehicle); BCG (2 × 10⁶ colony-forming units Connaught strain in 0.2 mL); imiquimod (20 mg/kg in 0.2 mL), and associated treatment BCG plus imiquimod in 0.2 mL. The bladders were extracted and analyzed for histopathology, immunohistochemistry, cell proliferation (Ki-67), apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling [TUNEL]), and immunoblotting for TLR2, TLR4, p-P70S6K, and p-4E-BP1 proteins.

RESULTS

The histopathology results showed that BCG and imiquimod decreased bladder tumorigenesis compared with the control group, with a proliferation decrease (Ki-67) and an apoptosis increase (TUNEL). BCG upregulated TLR2/4, imiquimod upregulated TLR4, and both downregulated P70S6K1.

CONCLUSION

Imiquimod is able to efficiently decrease bladder carcinogenesis through upregulation of TLR7/4 and downregulation of P70S6K1 protein, generating new perspectives to boost BCG effects in the future.

HDAC inhibition as a treatment concept to combat temsirolimus-resistant bladder cancer cells

Introduction

Although the mechanistic target of rapamycin (mTOR) might be a promising molecular target to treat advanced bladder cancer, resistance develops under chronic exposure to an mTOR inhibitor (everolimus, temsirolimus). Based on earlier studies, we proposed that histone deacetylase (HDAC) blockade might circumvent resistance and investigated whether HDAC inhibition has an impact on growth of bladder cancer cells with acquired resistance towards temsirolimus.

Results

The HDAC inhibitor valproic acid (VPA) significantly inhibited growth, proliferation and caused G0/G1 phase arrest in RT112^res and UMUC-3^res. cdk1, cyclin B, cdk2, cyclin A and Skp1 p19 were down-regulated, p27 was elevated. Akt-mTOR signaling was deactivated, whereas acetylation of histone H3 and H4 in RT112^res and UMUC-3^res increased in the presence of VPA. Knocking down cdk2 or cyclin A resulted in a significant growth blockade of RT112^res and UMUC-3^res.

Materials And Methods

Parental (par) and resistant (res) RT112 and UMUC-3 cells were exposed to the HDAC inhibitor VPA. Tumor cell growth, proliferation, cell cycling and expression of cell cycle regulating proteins were then evaluated. siRNA blockade was used to investigate the functional impact of the proteins.

Conclusions

HDAC inhibition induced a strong response of temsirolimus-resistant bladder cancer cells. Therefore, the temsirolimus-VPA-combination might be an innovative strategy for bladder cancer treatment.

Cuprous oxide nanoparticles inhibit the growth of cervical carcinoma by inducing autophagy

Cervical carcinoma is one of the main causes of women's cancer, and substantial side effects from standard treatment including platinum-based chemotherapy limit the options for escalation. In this paper, using cervical cancer cell lines and tumor-bearing mice as models, we report that CONPs could inhibit the proliferation of cancer cells in vitro and in vivo. Especially CONPs could inhibit tumor growth as cisplatin without weight loss. CONPs could also induce autophagy through AKT/mTOR pathway, which demonstrates that CONPs has the potential clinical applications.

[Analysis of contribution of protein phosphorylation in the development of the diseases]

In recent decades, studies in the molecular origins of socially significant diseases have made a big step forward with the development and using of high-performance methods in genomics and proteomics. Numerous studies in the framework of the global program "Human Proteome" were aimed at the identification of all possible proteins in various cell cultures and tissues, including cancer. One of the objectives was to identify biomarkers - proteins with high specificity to certain pathologies. However, in many cases, it is shown that the development of the disease is not associated with the appearance of new proteins, but depends on the level of gene expression or forming of proteoforms - splice variants, single amino acid substitutions (SAP variants), and post-translational modifications (PTM) of proteins. PTM may play a key role in the development of pathology because they activate a variety of regulatory or structural proteins in the majority of cell physiological processes. Phosphorylation is among the most significant of these protein modifications.This review will describe methods for analysis of protein phosphorylation used in the studies of such diseases as cancer and neurodegenerative diseases, as well as examples of cases when the modified proteins are involved directly to their development, and screening such significant PTM is used for the diagnosis and choice of treatment.

Phase I Clinical Trial of Everolimus Combined with Trimodality Therapy in Patients with Muscle-Invasive Bladder Cancer

Background: Local control following trimodality therapy (TMT) for muscle-invasive bladder cancer (MIBC) requires further optimization.

Objective: Evaluating the biologic endpoint, feasibility, and toxicity of integrating everolimus to TMT in patients with MIBC.

Methods: This was a phase I trial in patients with MIBC who were not surgical candidates or who refused cystectomy. Following maximal transurethral tumor resection, patients were treated by radiotherapy (50 Gy/20 fractions), gemcitabine (100 mg/m2/weekly) and escalating doses of everolimus (2.5–5.0 mg/day). Everolimus was given daily for one month prior to radiation, during treatment, and one month post-radiation. Toxicity assessment followed the Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring Criteria. Biologic endpoint with downregulation of phospho-S6 (pS6) was assessed using immunohistochemistry. Local response was evaluated with imaging and bladder biopsy post-therapy.

Results: 10 patients were recruited; 8 males, 2 females. Median age was 78 years (range: 63–85). Four patients entered everolimus 2.5 mg cohort. Six other patients entered everolimus 5.0 mg cohort. Toxicities were encountered in 2 patients (Grade I), 6 patients (Grade II), 9 patients (Grade III) and 1 patient (Grade IV), with some experiencing more than one toxicity. Most Grade III and IV toxicities were encountered from everolimus alone prior to combination testing. Trial was terminated early due to toxicity. Interestingly, 6/10 patients (60%) achieved a complete response with negative post-treatment biopsies. Significant decrease of pS6 was demonstrated post-therapy (p = 0.03).

Conclusions: Although combining everolimus with TMT achieved a biological endpoint and complete response in a significant number of patients with MIBC and negative prognostic factors, it was associated with unacceptable increased toxicity.

Proteomics analysis of bladder cancer invasion: Targeting EIF3D for therapeutic intervention

Patients with advanced bladder cancer have poor outcomes, indicating a need for more efficient therapeutic approaches. This study characterizes proteomic changes underlying bladder cancer invasion aiming for the better understanding of disease pathophysiology and identification of drug targets. High resolution liquid chromatography coupled to tandem mass spectrometry analysis of tissue specimens from patients with non-muscle invasive (NMIBC, stage pTa) and muscle invasive bladder cancer (MIBC, stages pT2+) was conducted. Comparative analysis identified 144 differentially expressed proteins between analyzed groups. These included proteins previously associated with bladder cancer and also additional novel such as PGRMC1, FUCA1, BROX and PSMD12, which were further confirmed by immunohistochemistry. Pathway and interactome analysis predicted strong activation in muscle invasive bladder cancer of pathways associated with protein synthesis e.g. eIF2 and mTOR signaling. Knock-down of eukaryotic translation initiation factor 3 subunit D (EIF3D) (overexpressed in muscle invasive disease) in metastatic T24M bladder cancer cells inhibited cell proliferation, migration, and colony formation in vitro and decreased tumor growth in xenograft models. By contrast, knocking down GTP-binding protein Rheb (which is upstream of EIF3D) recapitulated the effects of EIF3D knockdown in vitro, but not in vivo. Collectively, this study represents a comprehensive analysis of NMIBC and MIBC providing a resource for future studies. The results highlight EIF3D as a potential therapeutic target.

Oncological Impact of M-Tor Inhibitor Immunosuppressive Therapy after Liver Transplantation for Hepatocellular Carcinoma: Review of the Literature

Background: Hepatocellular Carcinoma (HCC) represents the fifth most common malignancy and the third cancer-related cause of death worldwide. Hepatitis B (HBV) and C (HCV) viral infections and alcohol abuse are the principal etiological factors for HCC. Liver transplantation (LT) is oncologically the preferable approach to HCC, as it can remove all the intrahepatic tumor foci, and also the oncogenic cirrhotic liver. The use of mTOR inhibitors (mTORi) for immunosuppression after LT for HCC has been proposed due to rapamycin antitumor activity. We decided to review the literature to clarify the oncological role of mTORi after liver transplantation for HCC, analyzing both present condition and future perspectives. Material and Methods: A systematic literature search was performed using PubMed, EMBASE, Scopus, and the Cochrane Library Central. The search was limited to studies in humans and to those reported in the English language in the period of time between January 2005 and December 2015. Results: The literature search yielded 93 articles; after duplicates were removed, 77 titles and abstracts were reviewed. Most relevant data and papers are herein reported and discussed. Conclusions: So far, the use of mTORi is encouraging in terms of oncological outcomes for patients underwent LT for HCC, both for prevention and treatment of HCC recurrence although definitive data are still awaited.