Targeted therapy for advanced prostate cancer: inhibition of the PI3K/Akt/mTOR pathway

Pleckstrin-2 Mediates the Activation of AKT in Prostate Cancer and Is Repressed by Androgen Receptor

Phosphoinositide 3-kinase (PI3K)-AKT and androgen receptor (AR) pathways are commonly activated in prostate cancers. Their reciprocal regulation makes advanced prostate cancers difficult to treat. The current study shows that pleckstrin-2 (PLEK2), a proto-oncoprotein involved in the activation and stabilization of AKT, connects these two pathways. Genetic evidence provided herein suggests that Plek2 deficiency largely reverted tumorigenesis in Pten prostate-specific knockout mice and that overexpression of PLEK2 promoted the proliferation and colony formation of prostate cancer cells in vitro. In addition, PLEK2 was negatively regulated by AR, AR transcriptionally repressed PLEK2 through binding to the PLEK2 promoter region, and overexpression of AR reduced PLEK2 expression, which inactivated AKT. Conversely, knockdown of AR in prostate cancer cells increased PLEK2 expression and activated the AKT pathway. This reciprocal inhibitory loop can be pharmacologically targeted using the PLEK2 inhibitor. PLEK2 inhibitor dose-dependently inhibited prostate cancer cell proliferation with the inactivation of AKT. Overall, the current study uncovered a crucial role of PLEK2 in prostate cancer proliferation and provided the rationale for targeting PLEK2 to treat prostate cancers.

Silencing APLNR enhances the radiosensitivity of prostate cancer by modulating the PI3K/AKT/mTOR signaling pathway

BACKGROUND

Aberrant expression of apelin receptor (APLNR) has been found to be involved in various cancers' development, however, its function in prostate cancer (PCa) remains unclear. The research aimed to investigate the role and potential mechanism of APLNR in PCa.

METHODS

The mRNA expression of APLNR was detected via qRT-PCR assay. PCa cell proliferation and apoptosis were determined through plate cloning and flow cytometry. In addition, the expression of apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) was evaluated using western blot. DNA damage marker (γ-H2AX) was analyzed by immunofluorescence and western blot. GSEA analysis was performed for seeking enrichment pathways of APLNR in PCa, and the protein levels of PI3K, p-PI3K, AKT, p-AKT, mTOR, and p-mTOR were tested using western blot.

RESULTS

APLNR expression was up-regulated in PCa tissues and cells. Silencing APLNR enhanced the sensitivity of PCa cells to radiotherapy, which was manifested by inhibiting cell proliferation, promoting cell apoptosis, and promoting DNA damage. Next, silencing APLNR inhibited the PI3K/AKT/mTOR pathway. Specifically, 740Y-P (the PI3K/AKT/mTOR pathway activator) reversed the effects of silencing APLNR on PCa cell proliferation, apoptosis and DNA damage.

CONCLUSION

Silencing APLNR inhibited cell proliferation, promoted cell apoptosis, and enhanced the radiosensitivity of PCa cells, which was involved in the PI3K/AKT/mTOR signaling pathway. This study is conducive to the deeper understanding of PCa and further provides a new perspective for the treatment of PCa.

Exploring potential therapeutic combinations for castration-sensitive prostate cancer using supercomputers: a proof of concept study

To address the challenge of finding new combination therapies against castration-sensitive prostate cancer, we introduce Vini, a computational tool that predicts the efficacy of drug combinations at the intracellular level by integrating data from the KEGG, DrugBank, Pubchem, Protein Data Bank, Uniprot, NCI-60 and COSMIC databases. Vini is a computational tool that predicts the efficacy of drugs and their combinations at the intracellular level. It addresses the problem comprehensively by considering all known target genes, proteins and small molecules and their mutual interactions involved in the onset and development of cancer. The results obtained point to new, previously unexplored combination therapies that could theoretically be promising candidates for the treatment of castration-sensitive prostate cancer and could prevent the inevitable progression of the cancer to the incurable castration-resistant stage. Furthermore, after analyzing the obtained triple combinations of drugs and their targets, the most common targets became clear: ALK, BCL-2, mTOR, DNA and androgen axis. These results may help to define future therapies against castration-sensitive prostate cancer. The use of the Vini computer model to explore therapeutic combinations represents an innovative approach in the search for effective treatments for castration-sensitive prostate cancer, which, if clinically validated, could potentially lead to new breakthrough therapies.

The Prognostic and Therapeutic Potential of Fragile X Mental Retardation 1 (FMR1) Gene Expression in Prostate Adenocarcinoma: Insights into Survival Outcomes and Oncogenic Pathway Modulation

Prostate adenocarcinoma (PRAD) is the second most common tumor associated with death. The role and mechanisms of the fragile X mental retardation 1 (FMR1) gene in PRAD remain unknown. We conducted an analysis of FMR1 expression in PRAD to determine its prognostic importance and connection to carcinogenic pathways such as PI3K_AKT_mTOR. Survival analyses were utilized to establish a correlation between FMR1 expression and patient outcomes. We used the integration of genomic data with bioinformatic predictions to predict the regulatory factors of the FMR1 gene in PRAD. Our data revealed that individuals with higher levels of FMR1 expression experience worse survival outcomes compared to those with lower expression (hazard ratio [HR] = 5.08, 95% confidence interval [CI] = 1.07 - 24, p = 0.0412). FMR1 expression was significantly higher in patients with advanced pathological tumor stages, particularly in the pT3 and pT4 combined stages and the pN1 nodal stage. Furthermore, patients with high Gleason scores (GSs) (combined GSs 8 and 9) exhibited increased levels of FMR1 expression. Our results further identify a possible regulatory link between FMR1 and key oncogenic pathways, including PI3K_AKT_mTOR, and predict the possible mechanism by which FMR1 is regulated in PRAD. Our data suggest that the FMR1 gene could serve as a biomarker for PRAD progression. However, in-depth investigations, including those with large patient samples and in vitro studies, are needed to validate this finding and understand the mechanisms involved.

Investigating the structural basis of piperine targeting AKT1 against prostate cancer through in vitro and molecular dynamics simulations

AkT1, significantly impacts many tumours cell functions, like transcription, apoptosis, glucose metabolism, cell proliferation, and cell migration. For tumours to develop and spread, aberrant activation of AKT1 is essential. Therefore, a major focus of molecularly targeted PCa treatment is AKT1. The present study investigates the effect of piperine compared to SDF using in-vitro studies, viz colony formation assay, comet assay and AKT1 gene expression studies using human PCa cell line PC3. A cluster of approximately at least 50 cells constitutes a colony. The clonogenic assay showed that the number and size of colonies significantly decreased when treated with compounds (SDF and piperine) in comparison to the untreated cells which effectively proliferated to form more colonies. Piperine treatment showed significant inhibition of colony formation than SDF. Effective genotoxicity was observed in piperine-treated PC3 cells with an increased Tail length of 120 µm and it was moderately observed in SDF with a Tail length of 30 µm treated on PC3 cells. The control group did not show any considerable genotoxicity with a Tail length of 6 µm. Our data, both in vitro and in silico, suggested that piperine would be a good starting point for developing novel drugs for the treatment of PCa. The downstream functions of Akt1 may be inhibited by these effects, which could impede the proliferation of PCa cells. High stability of the piperine-AKT1 complex was found by the MD simulation. Higher hydrophilic residues like Lys268 and Ser205 at the active pocket may be the cause of the binding stability. Overall, the observed results confirmed the anti-PCa effect of piperine by causing effective DNA damage and proved to be genotoxic in nature against the human PCa. These effects may impede the downstream activities of Akt1 and result in PCa cell growth regression.Communicated by Ramaswamy H. Sarma.

A common molecular and cellular pathway in developing Alzheimer and cancer

Globally cancer and Alzheimer's disease (AD) are two major diseases and still, there is no clearly defined molecular mechanism. There is an opposite relation between cancer and AD which are the proportion of emerging cancer was importantly slower in AD patients, whereas slow emerging AD in patients with cancer. In cancer, regulation of cell mechanisms is interrupted by an increase in cell survival and proliferation, while on the contrary, AD is related to augmented neuronal death, that may be either produced by or associated with amyloid-β (Aβ) and tau deposition. Stated that the probability that disruption of mechanisms takes part in the regulation of cell survival/death and might be implicated in both diseases. The mechanism of actions such as DNA-methylation, genetic polymorphisms, or another mechanism of actions that induce alteration in the action of drugs with significant roles in resolving the finding to repair and live or die might take part in the pathogenesis of these two ailments. The functions of miRNA, p53, Pin1, the Wnt signaling pathway, PI3 KINASE/Akt/mTOR signaling pathway GRK2 signaling pathway, and the pathophysiological role of oxidative stress are presented in this review as potential candidates which hypothetically describe inverse relations between cancer and AD. Innovative materials almost mutual mechanisms in the aetiology of cancer and AD advocates novel treatment approaches. Among these treatment strategies, the most promising use treatment such as tyrosine kinase inhibitor, nilotinib, protein kinase C, and bexarotene.

Molecular Targeting of the Phosphoinositide-3-Protein Kinase (PI3K) Pathway across Various Cancers

The dysregulation of the phosphatidylinositol-3-kinase (PI3K) pathway can lead to uncontrolled cellular growth and tumorigenesis. Targeting PI3K and its downstream substrates has been shown to be effective in preclinical studies and phase III trials with the approval of several PI3K pathway inhibitors by the Food and Drug Administration (FDA) over the past decade. However, the limited clinical efficacy of these inhibitors, intolerable toxicities, and acquired resistances limit the clinical application of PI3K inhibitors. This review discusses the PI3K signaling pathway, alterations in the PI3K pathway causing carcinogenesis, current and novel PI3K pathway inhibitors, adverse effects, resistance mechanisms, challenging issues, and future directions of PI3K pathway inhibitors.

Enhanced Chemoprevention of Prostate Cancer by Combining Arctigenin with Green Tea and Quercetin in Prostate-Specific Phosphatase and Tensin Homolog Knockout Mice

The low bioavailability of most phytochemicals limits their anticancer effects in humans. The present study was designed to test whether combining arctigenin (Arc), a lignan mainly from the seed of Arctium lappa, with green tea (GT) and quercetin (Q) enhances the chemopreventive effect on prostate cancer. We performed in vitro proliferation studies on different cell lines. We observed a strong synergistic anti-proliferative effect of GT+Q+Arc in exposing androgen-sensitive human prostate cancer LNCaP cells. The pre-malignant WPE1-NA22 cell line was more sensitive to this combination. No cytotoxicity was observed in normal prostate epithelial PrEC cells. For an in vivo study, 3-week-old, prostate-specific PTEN (phosphatase and tensin homolog) knockout mice were treated with GT+Q, Arc, GT+Q+Arc, or the control daily until 16 weeks of age. In vivo imaging using prostate-specific membrane antigen (PSMA) probes demonstrated that the prostate tumorigenesis was significantly inhibited by 40% (GT+Q), 60% (Arc at 30 mg/kg bw), and 90% (GT+Q+Arc) compared to the control. A pathological examination showed that all control mice developed invasive prostate adenocarcinoma. In contrast, the primary lesion in the GT+Q and Arc alone groups was high-grade prostatic intraepithelial neoplasia (PIN), with low-grade PIN in the GT+Q+Arc group. The combined effect of GT+Q+Arc was associated with an increased inhibition of the androgen receptor, the PI3K/Akt pathway, Ki67 expression, and angiogenesis. This study demonstrates that combining Arc with GT and Q was highly effective in prostate cancer chemoprevention. These results warrant clinical trials to confirm the efficacy of this combination in humans.

The Effect of Quercetin in the Yishen Tongluo Jiedu Recipe on the Development of Prostate Cancer through the Akt1-related CXCL12/ CXCR4 Pathway

BACKGROUND

It remains a challenge to effectively treat prostate cancer (PCa) that affects global men's health. It is essential to find a natural alternative drug and explore its antitumor mechanism due to the serious toxic side effects of chemotherapy.

METHODS

The targets and signaling pathways were analyzed by network pharmacology and verified by molecular docking and LC-MS. The proliferation, apoptosis, invasion, and migration of DU145 cells were detected by the CCK-8 method, flow cytometry, and Transwell, respectively. The Bcl-2, caspase-3, CXCL12, and CXCR4 expressions and Akt1 phosphorylation were determined by Western blot. Akt1 overexpression was applied to identify the involvement of the Akt1- related CXCL12/CXCR4 pathway in regulating PCa. Nude mouse tumorigenesis was performed to analyze the effect of quercetin on PCa in vivo.

RESULTS

Network pharmacology analysis displayed that quercetin was the main active component of the Yishen Tongluo Jiedu recipe and Akt1 was the therapy target of PCa. LC-MS analysis showed that quercetin existed in the Yishen Tongluo Jiedu recipe, and molecular docking proved that quercetin bound to Akt1. Quercetin inhibited the proliferation of DU145 cells by upregulating caspase-3 and downregulating Bcl-2 expression, promoting apoptosis and reducing invasion and migration abilities. In vivo, quercetin downregulated CXCL12 and CXCR4 expressions and inhibited PCa development by the Akt1-related CXCL12/CXCR4 pathway.

CONCLUSION

As the active component of the Yishen Tongluo Jiedu recipe, quercetin inhibited PCa development through the Akt1-related CXCL12/CXCR4 pathway. This study provided a new idea for PCa treatment and a theoretical basis for further research.

Elucidation of the Role of the Epigenetic Regulatory Mechanisms of PI3K/Akt/mTOR Signaling Pathway in Human Malignancies

The PI3K/Akt/mTOR pathway modulates cell growth, proliferation, metabolism, and movement. Moreover, significant studies have shown that the genes involved in this pathway are frequently activated in human cancer. Observational and computational modeling of the PI3K/AKt/ mTOR pathway inhibitors has been explored in clinical trials. It has been observed that the effectiveness and safety evidence from clinical studies and various inhibitors of this route have been given FDA approval. In this review article, we focused on the processes behind the overactivation of PI3K/Akt/mTOR signaling in cancer and provided an overview of PI3K/Akt/mTOR inhibitors as either individual drugs or a combination of different doses of drugs for different types of cancer. Furthermore, the review discusses the biological function and activation of the PI3K/AKt/mTOR signaling and their role in the development of cancers. Additionally, we discussed the potential challenges and corresponding prediction biomarkers of response and resistance for PI3K/Akt/m- TOR inhibitor development. The article focuses on the most current breakthroughs in using the PI3K/Akt/mTOR pathway to target certain molecules.

Synthesis and clinical application of small-molecule drugs approved to treat prostatic cancer

Prostate cancer is a prevalent form of cancer that primarily affects men, with a high incidence and mortality rate. It is the second most common cancer among males, following lung cancer. Typically occurring in individuals aged 50 and above, this malignant tumor originates from abnormal cells in the prostate tissue. If left untreated, it can spread to nearby tissues, lymph nodes, and even bones. Current treatment methods include surgery, radiotherapy, and chemotherapy. However, these treatments have certain limitations and side effects. Therefore, researching and developing new small-molecule drugs to treat prostate cancer is of great significance. In recent years, many small-molecule drugs have been proven to have therapeutic effects on prostate cancer. The purpose of this review is to give a comprehensive look at the clinical uses and synthetic methods of various significant small-molecule drugs that have been approved to treat prostate cancer, to facilitate the development of more powerful and innovative drugs for the effective control of prostate cancer.

Analysis of some flavonoids for inhibitory mechanism against cancer target phosphatidylinositol 3-kinase (PI3K) using computational tool

Cancer has been one of the leading causes of mortality worldwide over the past few years. Some progress has been made in the development of more effective cancer therapeutics, resulting in improved survival rates. However, the desired outcome in the form of successful treatment is yet to be achieved. There is high demand for the development of innovative, inexpensive, and effective anticancer treatments using natural resources. Natural compounds have been increasingly discovered and used for cancer therapy owing to their high molecular diversity, novel biofunctionality, and minimal side effects. These compounds can be utilized as chemopreventive agents because they can efficiently inhibit cell growth, control cell cycle progression, and block several tumor-promoting signaling pathways. PI3K is an important upstream protein of the PI3K-Akt-mTOR pathway and a well-established cancer therapeutic target. This study aimed to explore the small molecules, natural flavonoids, viz. quercetin, luteolin, kaempferol, genistein, wogonin, daidzein, and flavopiridol for PI3Kγ kinase activity inhibition. In this study, the binding pose, interacting residues, molecular interactions, binding energies, and dissociation constants were investigated. Our results showed that these flavonoids bound well with PI3Kγ with adequate binding strength scores and binding energy ranging from (-8.19 to -8.97 Kcal/mol). Among the explored ligands, flavopiridol showed the highest binding energy of -8.97 Kcal/mol, dock score (-44.40), and dissociation constant term, p K d of 6.58 against PI3Kγ. Based on the above results, the stability of the most promising ligand, flavopiridol, against PI3Kγ was evaluated by molecular dynamics simulations for 200 ns, confirming the stable flavopiridol and PI3Kγ complex. Our study suggests that among the selected flavonoids specifically flavopiridol may act as potential inhibitors of PI3Kγ and could be a therapeutic alternative to inhibit the PI3Kγ pathway, providing new insights into rational drug discovery research for cancer therapy.

Role of tissue markers associated with tumor microenvironment in the progression and immune suppression of oral squamous cell carcinoma

Head and neck cancers (HNC) continues to dominate major cancers contributing to  mortality worldwide. Squamous cell carcinoma is the major type of HNC. Oral Squamous Cell Carcinoma grouped under HNC is a malignant tumor occurring in the oral cavity. The primary risk factors of OSCC are tobacco, alcohol consumption, etc. This review focuses on modulations, mechanisms, growth and differentiation of oral squamous cell carcinoma. Cancer cell surrounds itself with a group of elements forming a favorable environment known as tumor microenvironment (TME). It consists of numerous cells which includes immune cells, blood cells and acellular components that are responsible for the progression, immunosuppression, metastasis and angiogenesis of cancer. This review highlights the most important tissue biomarkers (mTOR, CAF, FOXp3, CD163, CD33, CD34) that are associated with TME cells. mTOR remains as the primary regulator responsible in cancer and its importance towards immune-suppression is highlighted. Tumor-associated macrophages associated with cancer development and its relationship with immunomodulatory mechanism and Tregs, which are potential blockers of immune response and its mechanism and aberrations are discussed. Cancer-associated fibroblasts that are a part of TME and their role in evading the immune response and myeloid derived suppressor cells that have slight control over the immune response and their mechanism in the tumor progression is further explained. These markers have been emphasised as therapeutic targets and are currently in different stages of clinical trials.

EGFR is a potential dual molecular target for cancer and Alzheimer's disease

Many researchers are attempting to identify drugs that can be repurposed as effective therapies for Alzheimer's disease (AD). Several recent studies have highlighted epidermal growth factor receptor (EGFR) inhibitors approved for use as anti-cancer drugs as potential candidates for repurposing as AD therapeutics. In cancer, EGFR inhibitors target cell proliferation and angiogenesis, and studies in AD mouse models have shown that EGFR inhibitors can attenuate amyloid-beta (Aβ) pathology and improve cognitive function. In this review, we discuss the different functions of EGFR in cancer and AD and the potential of EGFR as a dual molecular target for AD diseases. In addition, we describe the effects of anti-cancer EGFR tyrosine kinase inhibitors (TKIs) on AD pathology and their prospects as therapeutic interventions for AD. By summarizing the physiological functions of EGFR in cancer and AD, this review emphasizes the significance of EGFR as an important molecular target for these diseases.

LINC01088/miR-22/CDC6 Axis Regulates Prostate Cancer Progression by Activating the PI3K/AKT Pathway

Background

Prostate cancer (PCa) harms the male reproductive system, and lncRNA may play an important role in it. Here, we report that the LINC01088/microRNA- (miRNA/miR-) 22/cell division cycle 6 (CDC6) axis regulated through the phosphatidylinositide 3-kinases- (PI3K-) protein kinase B (AKT) signaling pathway controls the development of PCa.

Methods

lncRNA/miRNA/mRNA associated with PCa was downloaded and analyzed by Gene Expression Omnibus. The expression and correlation of LINC01088/miR-22/CDC6 in PCa were analyzed and verified by RT-qPCR. Dual-luciferase was used to analyze the binding between miR-22 and LINC01088 or CDC6. Cell Counting Kit-8 and Transwell were used to analyze the effects of LINC01088/miR-22/CDC6 interactions on PCa cell viability or migration/invasion ability. Localization of LINC01088 in cells was analyzed by nuclear cytoplasmic separation. The effect of LINC01088/miR-22/CDC6 interaction on downstream PI3K/AKT signaling was analyzed by Western blot.

Results

LINC01088 or CDC6 was upregulated in prostate tumor tissues or cells, whereas miR-22 was downregulated, miR-22 directly targets both LINC01088 and CDC6. si-LINC01088 inhibits the PCa process by suppressing the PI3K/AKT pathway. CDC6 reverses si-linc01088-mediated cell growth inhibition and reduction of PI3K and AKT protein levels.

Conclusion

Our results demonstrate that the LINC01088/miR-22/CDC6 axis functions in PCa progression and provide a promising diagnostic and therapeutic target.

Human embryonic stem cells exert antitumor effects on prostate cancer cells in a co-culture microenvironment

Prostate cancer is currently the most common malignancy among men. Given the limitations of current conventional anticancer therapies, new high-risk treatments are urgently needed. Previous studies have shown that embryonic stem cells (ESCs) can reverse the tumorigenic phenotype of tumor cells. However, there are still challenges in using human ESCs (hESCs) directly in cancer treatment. To facilitate the practical application of hESCs, we established a co-culture system consisting of prostate cancer cell lines and hESCs and investigated the antitumor activity of the supernatant of the co-culture system (Co-Sp) in vitro and in vivo, as well as the underlying mechanisms involved. The Co-Sp decreased the viability of prostate cancer cells in a concentration-dependent manner, significantly inhibited colony formation, and induced cell cycle arrest at the G0/G1 phase of the cell cycle. In addition, Co-Sp promoted apoptosis of prostate cancer cells and inhibited cell migration and invasion. In vivo studies also revealed that Co-Sp inhibited tumor growth in the xenograft model. Mechanistic studies showed that Co-Sp reduced the expression of cyclin D1, cyclin E, CDK4, CDK2, MMP-9, MMP-1, and Bcl-2, and increased the expression of p21, cleaved caspase-9, cleaved caspase-3, cleaved PARP, and Bax in prostate cancer cells. Furthermore, the Co-Sp decreased the phosphorylation of PI3K, AKT, and mTOR in cells and tumor tissues. Taken together, our results indicated that the Co-Sp has potent antitumor activity and could directly inhibit tumor growth. Our findings provide a new and effective way for the application of hESCs in cancer therapy and contribute to a new strategy for clinical stem cell therapy.

Pyrogallol from Spirogyra neglecta Inhibits Proliferation and Promotes Apoptosis in Castration-Resistant Prostate Cancer Cells via Modulating Akt/GSK-3β/β-catenin Signaling Pathway

Castration-resistant prostate cancer (CRPC) is an advanced form of prostate cancer associated with poor survival rates. The high proliferation and metastasis rates have made CRPC one of the most challenging types of cancer for medical practitioners and researchers. In this study, the anti-cancer properties and inhibition of CRPC progression by S. neglecta extract and its active constituents were determined using two CRPC cell lines, DU145 and PC3. The ethyl acetate fraction of S. neglecta (SnEA) was obtained using a solvent-partitioned extraction technique. The active constituents of SnEA were then determined using the HPLC technique, which showed that SnEA mainly contained syringic acid, pyrogallol, and p-coumaric acid phenolic compounds. After the determination of cytotoxic properties using the SRB assay, it was found that pyrogallol, but not the other two major compounds of SnEA, displayed promising anti-cancer properties in both CRPC cell lines. SnEA and pyrogallol were then further investigated for their anti-proliferation and apoptotic induction properties using propidium iodide and Annexin V staining. The results showed that SnEA and pyrogallol inhibited both DU145 and PC3 cell proliferation by inducing cell cycle arrest in the G0/G1 phase and significantly decreased the expression of cell cycle regulator proteins (cyclin D1, cyclin E1, CDK-2, and CDK-4, p < 0.001). SnEA and pyrogallol treatments also promoted apoptosis in both types of CRPC cells through significantly downregulating anti-apoptotic proteins (survivin, Bcl-2, and Bcl-xl, p < 0.001) and upregulating apoptotic proteins (cleaved-caspase-9, cleaved-caspase-3 and cleaved-PARP-1, p < 0.001). Mechanistic study demonstrated that SnEA and pyrogallol inactivated the Akt signaling pathway leading to enhancement of the active form of GSK-3β in CRPC cell lines. Therefore, the phosphorylation of β-catenin was increased, which caused degradation of the protein, resulting in a downregulation of β-catenin (unphosphorylated form) transcriptional factor activity. The current results reflect the potential impact of S. neglecta extract and pyrogallol on the management of castration-resistant prostate cancer.

Anti-Cancer Stem-Cell-Targeted Therapies in Prostate Cancer

Prostate cancer (PCa) is the second-most commonly diagnosed cancer in men around the world. It is treated using a risk stratification approach in accordance with the National Comprehensive Cancer Network (NCCN) in the United States. The main treatment options for early PCa include external beam radiation therapy (EBRT), brachytherapy, radical prostatectomy, active surveillance, or a combination approach. In those with advanced disease, androgen deprivation therapy (ADT) is considered as a first-line therapy. However, the majority of cases eventually progress while receiving ADT, leading to castration-resistant prostate cancer (CRPC). The near inevitable progression to CRPC has spurred the recent development of many novel medical treatments using targeted therapies. In this review, we outline the current landscape of stem-cell-targeted therapies for PCa, summarize their mechanisms of action, and discuss avenues of future development.

Statins block mammalian target of rapamycin pathway: a possible novel therapeutic strategy for inflammatory, malignant and neurodegenerative diseases

Inflammation plays a critical role in several diseases such as cancer, gastric, heart and nervous system diseases. Data suggest that the activation of mammalian target of rapamycin (mTOR) pathway in epithelial cells leads to inflammation. Statins, the inhibitors of the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA), seem to be able to inhibit the mTOR. Statins are considered to have favorable effects on inflammatory diseases by reducing the complications caused by inflammation and by regulating the inflammatory process and cytokines secretion. This critical review collected data on this topic from clinical, in vivo and in vitro studies published between 1998 and June 2022 in English from databases including PubMed, Google Scholar, Scopus, and Cochrane libraries.

A compendium of Androgen Receptor Variant 7 target genes and their role in Castration Resistant Prostate Cancer

Persistent androgen receptor (AR) signalling is the main driver of prostate cancer (PCa). Truncated isoforms of the AR called androgen receptor variants (AR-Vs) lacking the ligand binding domain often emerge during treatment resistance against AR pathway inhibitors such as Enzalutamide. This review discusses how AR-Vs drive a more aggressive form of PCa through the regulation of some of their target genes involved in oncogenic pathways, enabling disease progression. There is a pressing need for the development of a new generation of AR inhibitors which can repress the activity of both the full-length AR and AR-Vs, for which the knowledge of differentially expressed target genes will allow evaluation of inhibition efficacy. This review provides a detailed account of the most common variant, AR-V7, the AR-V7 regulated genes which have been experimentally validated, endeavours to understand their relevance in aggressive AR-V driven PCa and discusses the utility of the downstream protein products as potential drug targets for PCa treatment.

Potential Phytochemicals for Prevention of Familial Breast Cancer with BRCA Mutations

Breast cancer has remained a global challenge and the second leading cause of cancer mortality in women and family history. Hereditary factors are some of the major risk factors associated with breast cancer. Out of total breast cancer cases, 5-10% account only for familial breast cancer, and nearly 50% of all hereditary breast cancer are due to BRCA1/BRCA2 germline mutations. BRCA1/2 mutations play an important role not only in determining the clinical prognosis of breast cancer but also in the survival curves. Since this risk factor is known, a significant amount of the healthcare burden can be reduced by taking preventive measures among people with a known history of familial breast cancer. There is increasing evidence that phytochemicals of nutrients and supplements help in the prevention and cure of BRCA-related cancers by different mechanisms such as limiting DNA damage, altering estrogen metabolism, or upregulating expression of the normal BRCA allele, and ultimately enhancing DNA repair. This manuscript reviews different approaches used to identify potential phytochemicals to mitigate the risk of familial breast cancer with BRCA mutations. The findings of this review can be extended for the prevention and cure of any BRCAmutated cancer after proper experimental and clinical validation of the data.

Gnetin C Intercepts MTA1-Associated Neoplastic Progression in Prostate Cancer

Nutritional chemoprevention is particularly suitable for prostate cancer. Gnetin C, a resveratrol dimer found abundantly in the melinjo plant (Gnetum gnemon), may possess more potent biological properties compared to other stilbenes. We examined the effects of gnetin C in a high-risk premalignant transgenic mouse model overexpressing tumor-promoting metastasis-associated protein 1 (MTA1) on the background of Pten heterozygosity (R26^MTA1; Pten^+/f; Pb-Cre⁺). Mice were fed diets supplemented with the following compounds: pterostilbene (70 mg/kg diet); gnetin C, high dose (70 mg/kg diet); and gnetin C, low dose (35 mg/kg diet). Prostate tissues were isolated after 17 weeks and examined for histopathology and molecular markers. Serum was analyzed for cytokine expression. Gnetin C-supplemented diets substantially delayed the progression of preneoplastic lesions compared to other groups. Prostate tissues from gnetin C-fed mice showed favorable histopathology, with decreased severity and number of prostatic intraepithelial neoplasia (PIN) foci, reduced proliferation, and angiogenesis. A decreased level of MTA1, concurrent with the trend of increasing phosphatase and tensin homolog expression and reduced interleukin 2 (IL-2) levels in sera, were also detected in gnetin C-fed mice. Importantly, gnetin C did not exert any visible toxicity in mice. Our findings demonstrate that a gnetin C-supplemented diet effectively blocks MTA1-promoted tumor progression activity in high-risk premalignant prostate cancer, which indicates its potential as a novel form of nutritional interception for prostate cancer chemoprevention.

Targeting mTOR Complex 2 in Castration-Resistant Prostate Cancer with Acquired Docetaxel Resistance

PURPOSE

Mammalian Target of rapamycin (mTOR) plays a central role in regulating cell growth, proliferation, and cell cycle. The key component of mTORC2 is highly expressed in docetaxel-resistant prostate cells. However, the underlying molecular effects on prostate cells remain unclear.

METHODS

A docetaxel-resistant human prostate cell line (PC-3/DTX) was constructed to investigate the role of mTORC2 in docetaxel resistance. The lentivirus was transfected into cells to knock down the expression of Rictor, and cell viability was measured by Cell Counting Kit 8 (CCK-8). Flow cytometry was used to analyze the cell cycle, and the changes in related signal cascades were assessed by immunohistochemistry (IHC) staining and Western blot.

RESULTS

Docetaxel showed the lowest IC50 (50% inhibitory concentration) in PC-3/DTX cells with sh-RNA. Decreased Rictor expression resulted in a larger proportion of arrested cells in the G0/G1 phase in PC-3/DTX cells. The IC50 values of the AZD8055 group were lower than in the Rapamycin group when treated with docetaxel again. Furthermore, a larger proportion of PC-3/DTX cells were arrested in the G0/G1 phase in the AZD8055 group compared to the Rapamycin group. The IHC results of the prostate cancer tissues from a CRPC patient revealed the over expression of Rictor only, while Raptor expression was unaffected.

CONCLUSION

We investigated the role of mTORC2 signaling on the acquired docetaxel -resistant PC-3 cells to identify potential methods for clinical treatment. MTORC2 expression is essential for docetaxel drug resistance of PC-3 cells. The mTORC1/2 inhibitor AZD8055 caused more significant disruption of mTORC2 kinase activity than the mTORC1 inhibitor Rapamycin, which lead to decreased docetaxel-mediated resistance. Therefore, reversing docetaxel resistance, may become a therapeutic option in the treatment of mCRPC patients.

Whole-exome sequencing reveals a comprehensive germline mutation landscape and identifies twelve novel predisposition genes in Chinese prostate cancer patients

Prostate cancer is the most inheritable cancer with approximately 42% of disease risk attributed to inherited factors by studies of twins, indicating the importance of additional genetic screening to identify predisposition variants. However, only DNA damage repair (DDR) genes have been investigated thoroughly in prostate cancer. To determine the comprehensive germline mutation landscape in Chinese prostate cancer patients, we performed whole exome sequencing in 100 Han Chinese patients with prostate cancer in Hong Kong and identified deleterious germline mutations. A total of 36 deleterious germline variants in 25 genes were identified in 29% patients. Variants were found in eight pathways, including DNA methylation, DDR, and tyrosine-protein kinase. These findings were validated in an independent Chinese cohort of 167 patients with prostate cancer in Shanghai. Seven common deleterious-variant-containing genes were found in discovery cohort (7/25, 28%) and validation cohort (7/28, 25%) with three genes not described before (LDLR, MYH7 and SUGCT) and four genes previously reported (FANCI, ITGA6, PABPC1 and RAD54B). When comparing with that of a cohort of East Asian healthy individuals, 12 non-DDR novel potential predisposition genes (ADGRG1, CHD4, DNMT3A, ERBB3, GRHL1, HMBS, LDLR, MYH7, MYO6, NT5C2, NUP98 and SUGCT) were identified using the discovery and validation cohorts, which have not been previously reported in prostate cancer patients in all ethnic groups. Taken together, this study reveals a comprehensive germline mutation landscape in Chinese prostate cancer patients and discovers 12 novel non-DDR predisposition genes to lay the groundwork for the optimization of genetic screening.

Prostate cancer is the most inheritable cancer with about 42% of disease risk attributed to inherited factors, indicating the importance of additional genetic screening to identify predisposition variants. However, only DNA damage repair (DDR) genes have been studied thoroughly in prostate cancer. To determine the comprehensive germline mutation landscape in Chinese prostate cancer patients, we performed whole exome sequencing in 100 Han Chinese patients with prostate cancer in Hong Kong and identified deleterious germline mutations. A total of 36 deleterious germline variants in 25 genes were identified in 29% patients. Variants were found in eight pathways, including DNA methylation, DDR, and tyrosine-protein kinase. These findings were validated in an independent Chinese cohort of 167 patients with prostate cancer in Shanghai. Seven common deleterious-variant-containing genes were found in discovery cohort and validation cohort with three genes not described before (LDLR, MYH7 and SUGCT) and four genes previously reported. When comparing with that of a cohort of East Asian healthy individuals, 12 non-DDR novel potential predisposition genes were identified using the discovery and validation cohorts, which have not been previously reported in prostate cancer patients in all ethnic groups.

Crocin molecular signaling pathways at a glance: A comprehensive review

Crocin is a hydrophilic carotenoid that is synthesized in the flowers of the Crocus genus. Numerous in vitro and in vivo research projects have been published about the biological and pharmacological properties and toxicity of crocin. Crocin acts as a memory enhancer, anxiolytic, aphrodisiac, antidepressant, neuroprotective, and so on. Here, we introduce an updated and comprehensive review of crocin molecular mechanisms based on previously examined and mentioned in the literature. Different studies confirmed the significant effect of crocin to control pathological conditions, including oxidative stress, inflammation, metabolic disorders, neurodegenerative disorders, and cancer. The neuroprotective effect of crocin could be related to the activation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT)/mammalian target of rapamycin (mTOR), Notch, and cyclic-AMP response element-binding protein signaling pathways. The crocin also protects the cardiovascular system through the inhibitory effect on toll-like receptors. The regulatory effect of crocin on PI3K/AKT/mTOR, AMP-activated protein kinase, mitogen-activated protein kinases (MAPK), and peroxisome proliferator-activated receptor pathways can play an effective role in the treatment of metabolic disorders. The crocin has anticancer activity through the PI3K/AKT/mTOR, MAPK, vascular endothelial growth factor, Wnt/β-catenin, and Janus kinases-signal transducer and activator of transcription suppression. Also, the nuclear factor-erythroid factor 2-related factor 2 and p53 signaling pathway activation may be effective in the anticancer effect of crocin. Finally, among signaling pathways regulated by crocin, the most important ones seem to be those related to the regulatory effect on the PI3K/AKT/mTOR pathway.

Pyruvate Kinase M1 Suppresses Development and Progression of Prostate Adenocarcinoma

SIGNIFICANCE

Differential expression of PKM1 and PKM2 impacts prostate tumorigenesis and suggests a potential therapeutic vulnerability in prostate cancer.

Transcriptome-wide prediction of prostate cancer gene expression from histopathology images using co-expression based convolutional neural networks

Motivation

Molecular phenotyping by gene expression profiling is central in contemporary cancer research and in molecular diagnostics but remains resource intense to implement. Changes in gene expression occurring in tumours cause morphological changes in tissue, which can be observed on the microscopic level. The relationship between morphological patterns and some of the molecular phenotypes can be exploited to predict molecular phenotypes from routine haematoxylin and eosin-stained whole slide images (WSIs) using convolutional neural networks (CNNs). In this study, we propose a new, computationally efficient approach to model relationships between morphology and gene expression.

Results

We conducted the first transcriptome-wide analysis in prostate cancer, using CNNs to predict bulk RNA-sequencing estimates from WSIs for 370 patients from the TCGA PRAD study. Out of 15 586 protein coding transcripts, 6618 had predicted expression significantly associated with RNA-seq estimates (FDR-adjusted P-value <1×10⁻⁴) in a cross-validation and 5419 (81.9%) of these associations were subsequently validated in a held-out test set. We furthermore predicted the prognostic cell-cycle progression score directly from WSIs. These findings suggest that contemporary computer vision models offer an inexpensive and scalable solution for prediction of gene expression phenotypes directly from WSIs, providing opportunity for cost-effective large-scale research studies and molecular diagnostics.

Availability and implementation

A self-contained example is available from http://github.com/phiwei/prostate_coexpression. Model predictions and metrics are available from doi.org/10.5281/zenodo.4739097.

Supplementary information

Supplementary data are available at Bioinformatics online.

A Pleiotropic Role of Long Non-Coding RNAs in the Modulation of Wnt/β-Catenin and PI3K/Akt/mTOR Signaling Pathways in Esophageal Squamous Cell Carcinoma: Implication in Chemotherapeutic Drug Response

Despite the availability of modern techniques for the treatment of esophageal squamous cell carcinoma (ESCC), tumor recurrence and metastasis are significant challenges in clinical management. Thus, ESCC possesses a poor prognosis and low five-year overall survival rate. Notably, the origin and recurrence of the cancer phenotype are under the control of complex cancer-related signaling pathways. In this review, we provide comprehensive knowledge about long non-coding RNAs (lncRNAs) related to Wnt/β-catenin and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway in ESCC and its implications in hindering the efficacy of chemotherapeutic drugs. We observed that a pool of lncRNAs, such as HERES, TUG1, and UCA1, associated with ESCC, directly or indirectly targets various molecules of the Wnt/β-catenin pathway and facilitates the manifestation of multiple cancer phenotypes, including proliferation, metastasis, relapse, and resistance to anticancer treatment. Additionally, several lncRNAs, such as HCP5 and PTCSC1, modulate PI3K/Akt/mTOR pathways during the ESCC pathogenesis. Furthermore, a few lncRNAs, such as AFAP1-AS1 and LINC01014, block the efficiency of chemotherapeutic drugs, including cisplatin, 5-fluorouracil, paclitaxel, and gefitinib, used for ESCC treatment. Therefore, this review may help in designing a better therapeutic strategy for ESCC patients.

Overview of the Development and Use of Akt Inhibitors in Prostate Cancer

Deregulation of the PI3K-Akt-mTOR pathway plays a critical role in the development and progression of many cancers. In prostate cancer, evidence suggests that it is mainly driven by PTEN loss of function. For many years, the development of selective Akt inhibitors has been challenging. In recent phase II and III clinical trials, Ipatasertib and Capivasertib associated with androgen deprivation therapies showed promising outcomes in patients with metastatic castration-resistant prostate cancer and PTEN-loss. Ongoing trials are currently assessing several Akt inhibitors in prostate cancer with different combinations, at different stages of the disease.

Identifying and characterizing lincRNA genomic clusters reveals its cooperative functions in human cancer

Background

Emerging evidence has revealed that some long intergenic non-coding RNAs (lincRNAs) are likely to form clusters on the same chromosome, and lincRNA genomic clusters might play critical roles in the pathophysiological mechanism. However, the comprehensive investigation of lincRNA clustering is rarely studied, particularly the characterization of their functional significance across different cancer types.

Methods

In this study, we firstly constructed a computational method basing a sliding window approach for systematically identifying lincRNA genomic clusters. We then dissected these lincRNA genomic clusters to identify common characteristics in cooperative expression, conservation among divergent species, targeted miRNAs, and CNV frequency. Next, we performed comprehensive analyses in differentially-expressed patterns and overall survival outcomes for patients from The Cancer Genome Atlas (TCGA) and The Genotype-Tissue Expression (GTEx) across multiple cancer types. Finally, we explored the underlying mechanisms of lincRNA genomic clusters by functional enrichment analysis, pathway analysis, and drug-target interaction.

Results

We identified lincRNA genomic clusters according to the algorithm. Clustering lincRNAs tended to be co-expressed, highly conserved, targeted by more miRNAs, and with similar deletion and duplication frequency, suggesting that lincRNA genomic clusters may exert their effects by acting in combination. We further systematically explored conserved and cancer-specific lincRNA genomic clusters, indicating they were involved in some important mechanisms of disease occurrence through diverse approaches. Furthermore, lincRNA genomic clusters can serve as biomarkers with potential clinical significance and involve in specific pathological processes in the development of cancer. Moreover, a lincRNA genomic cluster named Cluster127 in DLK1-DIO3 imprinted locus was discovered, which contained MEG3, MEG8, MEG9, MIR381HG, LINC02285, AL132709.5, and AL132709.1. Further analysis indicated that Cluster127 may have the potential for predicting prognosis in cancer and could play their roles by participating in the regulation of PI3K-AKT signaling pathway.

Conclusions

Clarification of the lincRNA genomic clusters specific roles in human cancers could be beneficial for understanding the molecular pathogenesis of different cancer types.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03179-5.

Evaluation of autophagy mediators in myeloid-derived suppressor cells during human tuberculosis

Myeloid-derived suppressor cells (MDSC) are induced during active TB disease to restore immune homeostasis but instead exacerbate disease outcome due to chronic inflammation. Autophagy, in conventional phagocytes, ensures successful clearance of M.tb. However, autophagy has been demonstrated to induce prolonged MDSC survival. Here we investigate the relationship between autophagy mediators and MDSC in the context of active TB disease and during anti-TB therapy. We demonstrate a significant increase in MDSC frequencies in untreated active TB cases with these MDSC expressing TLR4 and significantly more mTOR and IL-6 than healthy controls, with mTOR levels decreasing during anti-TB therapy. Finally, we show that HMGB1 serum concentrations decrease in parallel with mTOR. These findings suggest a complex interplay between MDSC and autophagic mediators, potentially dependent on cellular localisation and M.tb infection state.

Inhibitors of the PI3K/Akt/mTOR Pathway in Prostate Cancer Chemoprevention and Intervention

The phosphatidylinositol 3-kinase (PI3K)/serine-threonine kinase (Akt)/mammalian target of the rapamycin (mTOR)-signaling pathway has been suggested to have connections with the malignant transformation, growth, proliferation, and metastasis of various cancers and solid tumors. Relevant connections between the PI3K/Akt/mTOR pathway, cell survival, and prostate cancer (PC) provide a great therapeutic target for PC prevention or treatment. Recent studies have focused on small-molecule mTOR inhibitors or their usage in coordination with other therapeutics for PC treatment that are currently undergoing clinical testing. In this study, the function of the PI3K/Akt/mTOR pathway, the consequence of its dysregulation, and the development of mTOR inhibitors, either as an individual substance or in combination with other agents, and their clinical implications are discussed. The rationale for targeting the PI3K/Akt/mTOR pathway, and specifically the application and potential utility of natural agents involved in PC treatment is described. In addition to the small-molecule mTOR inhibitors, there are evidence that several natural agents are able to target the PI3K/Akt/mTOR pathway in prostatic neoplasms. These natural mTOR inhibitors can interfere with the PI3K/Akt/mTOR pathway through multiple mechanisms; however, inhibition of Akt and suppression of mTOR 1 activity are two major therapeutic approaches. Combination therapy improves the efficacy of these inhibitors to either suppress the PC progression or circumvent the resistance by cancer cells.

Urine organic acids may be useful biomarkers for metabolic syndrome and its components in Korean adults

OBJECTIVES

Although metabolic syndrome (MetS) and its components are defined clinically, those with MetS may have various derangements in metabolic pathways. Thus, this study aimed to evaluate the traits of urine organic acid metabolites indicating the metabolic intermediates of the pathways in the subjects with MetS.

METHODS

This cross-sectional study included 246 men and 283 women in a hospital health check-up setting. Urine organic acid metabolites were assayed via high-performance liquid chromatography-mass spectrometry analyses. A high level of each metabolite was defined as the fifth quintile of the distribution.

RESULTS

The subjects with MetS had high levels of pyruvate, α-ketoglutarate, α-ketoisovalerate, α-ketoisocaproate, formiminoglutamate, and quinolinate (odds ratios from 1.915 to 2.809 in logistic models adjusted for age and sex). Among the metabolites, pyruvate, formiminoglutamate, and quinolinate were not independent of homeostatic model assessment of insulin resistance (HOMA2-IR). Several metabolites were associated with one or more components of MetS and HOMA2-IR.

CONCLUSIONS

Urine organic acid metabolites in MetS are characterized in altered carbohydrate and amino acid metabolism. MetS shared some traits in insulin resistance. These findings may promote the understanding of the pathophysiology of MetS.

SPLICE-q: a Python tool for genome-wide quantification of splicing efficiency

BACKGROUND

Introns are generally removed from primary transcripts to form mature RNA molecules in a post-transcriptional process called splicing. An efficient splicing of primary transcripts is an essential step in gene expression and its misregulation is related to numerous human diseases. Thus, to better understand the dynamics of this process and the perturbations that might be caused by aberrant transcript processing it is important to quantify splicing efficiency.

RESULTS

Here, we introduce SPLICE-q, a fast and user-friendly Python tool for genome-wide SPLICing Efficiency quantification. It supports studies focusing on the implications of splicing efficiency in transcript processing dynamics. SPLICE-q uses aligned reads from strand-specific RNA-seq to quantify splicing efficiency for each intron individually and allows the user to select different levels of restrictiveness concerning the introns' overlap with other genomic elements such as exons of other genes. We applied SPLICE-q to globally assess the dynamics of intron excision in yeast and human nascent RNA-seq. We also show its application using total RNA-seq from a patient-matched prostate cancer sample.

CONCLUSIONS

Our analyses illustrate that SPLICE-q is suitable to detect a progressive increase of splicing efficiency throughout a time course of nascent RNA-seq and it might be useful when it comes to understanding cancer progression beyond mere gene expression levels. SPLICE-q is available at: https://github.com/vrmelo/SPLICE-q.

Attacking the PI3K/Akt/mTOR signaling pathway for targeted therapeutic treatment in human cancer

Cancer is the second leading cause of human death globally. PI3K/Akt/mTOR signaling is one of the most frequently dysregulated signaling pathways observed in cancer patients that plays crucial roles in promoting tumor initiation, progression and therapy responses. This is largely due to that PI3K/Akt/mTOR signaling is indispensable for many cellular biological processes, including cell growth, metastasis, survival, metabolism, and others. As such, small molecule inhibitors targeting major kinase components of the PI3K/Akt/mTOR signaling pathway have drawn extensive attention and been developed and evaluated in preclinical models and clinical trials. Targeting a single kinase component within this signaling usually causes growth arrest rather than apoptosis associated with toxicity-induced adverse effects in patients. Combination therapies including PI3K/Akt/mTOR inhibitors show improved patient response and clinical outcome, albeit developed resistance has been reported. In this review, we focus on revealing the mechanisms leading to the hyperactivation of PI3K/Akt/mTOR signaling in cancer and summarizing efforts for developing PI3K/Akt/mTOR inhibitors as either mono-therapy or combination therapy in different cancer settings. We hope that this review will facilitate further understanding of the regulatory mechanisms governing dysregulation of PI3K/Akt/mTOR oncogenic signaling in cancer and provide insights into possible future directions for targeted therapeutic regimen for cancer treatment, by developing new agents, drug delivery systems, or combination regimen to target the PI3K/Akt/mTOR signaling pathway. This information will also provide effective patient stratification strategy to improve the patient response and clinical outcome for cancer patients with deregulated PI3K/Akt/mTOR signaling.

mTOR pathway and DNA damage response: A therapeutic strategy in cancer therapy

The mammalian target of rapamycin (mTOR) is a conserved serine/threonine-protein kinase, comprising two subunit protein complexes: mTORC1 and mTORC2. In response to insult and cancer, the mTOR pathway plays a crucial role in regulating growth, metabolism, cell survival, and protein synthesis. Key subunits of mTORC1/2 catalyze the phosphorylation of various molecules, including eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), ribosomal protein S6 kinase β-1 (S6K1). The DNA damage response (DDR) maintains genomic stability and provides an opportunity for treating tumors with defects caused by DNA damaging agents. Many mTOR inhibitors are utilized for the treatment of cancers. However, several clinical trials are still assessing the efficacy of mTOR inhibitors. This paper discusses the role of the mTOR signaling pathway and its regulators in developing cancer. In the following, we will review the interaction between DDR and mTOR signaling and the innovative therapies applied in preclinical and clinical trials for treating cancers.

Integrated bioinformatic analysis and experiment confirmation of the antagonistic effect and molecular mechanism of ginsenoside Rh2 in metastatic osteosarcoma

This study aimed to compare the gene expression variation of clinical primary osteosarcoma (OS) and metastatic OS, identify expression profiles and signal pathways related to disease classification, and systematically evaluate the potential anticancer effect and molecular mechanism of ginsenoside Rh2 on OS. A raw dataset (GSE14359), which excluded GSM359137 and GSM359138, was downloaded from the Gene Expression Omnibus. Differentially expressed genes (DEGs) and principal component analysis (PCA) were obtained with limma. Pathways enrichment analysis was understood by GSEA app. Rh2-associated targets were harvested and mapped through PharmMapper and Cytoscape 3.4.0. The toxicity of Rh2 was determined using crystal staining and MTT assay on 143B and MG63 cell lines. The relative protein expression was confirmed through Western blot analysis. The mitochondrial membrane potential (△Ψm) was evaluated by JC-1 fluorescence staining. The cell mobility was measured via wound healing and transwell assays. A total of 752 genes were upregulated, while 161 genes were downregulated. GSEA and PCA displayed significant function enrichment and classification. Through PharmMapper and Cytoscape 3.4.0, Rh2 was found to target the mitogen activated protein kinase (MAPK) and PI3K signaling pathways, which are the key pathways in the metastasis of OS. Furthermore, Rh2 induced a concentration-dependent decrease in cell viability and early apoptosis associated with ΔΨm decline, while a non-lethal dose of Rh2 weakened the metastatic capability. Moreover, systematic evaluation showed that promoting the MAPK signaling pathway and inhibiting PI3K/Akt/mTOR were correlated with the anticancer effects of Rh2 on metastatic OS. In conclusion, transcriptome-derived approaches may be beneficial in diagnosing early metastases, and Rh2, a multi-targeting agent, shows promising application potential in suppressing metastatic OS in an MAPK- and PI3K/Akt/mTOR-dependent manner.

A New Insight for the Identification of Oncogenic Variants in Breast and Prostate Cancers in Diverse Human Populations, With a Focus on Latinos

Background: Breast cancer (BRCA) and prostate cancer (PRCA) are the most commonly diagnosed cancer types in Latin American women and men, respectively. Although in recent years large-scale efforts from international consortia have focused on improving precision oncology, a better understanding of genomic features of BRCA and PRCA in developing regions and racial/ethnic minority populations is still required.

Methods: To fill in this gap, we performed integrated in silico analyses to elucidate oncogenic variants from BRCA and PRCA driver genes; to calculate their deleteriousness scores and allele frequencies from seven human populations worldwide, including Latinos; and to propose the most effective therapeutic strategies based on precision oncology.

Results: We analyzed 339,100 variants belonging to 99 BRCA and 82 PRCA driver genes and identified 18,512 and 15,648 known/predicted oncogenic variants, respectively. Regarding known oncogenic variants, we prioritized the most frequent and deleterious variants of BRCA (n = 230) and PRCA (n = 167) from Latino, African, Ashkenazi Jewish, East Asian, South Asian, European Finnish, and European non-Finnish populations, to incorporate them into pharmacogenomics testing. Lastly, we identified which oncogenic variants may shape the response to anti-cancer therapies, detailing the current status of pharmacogenomics guidelines and clinical trials involved in BRCA and PRCA cancer driver proteins.

Conclusion: It is imperative to unify efforts where developing countries might invest in obtaining databases of genomic profiles of their populations, and developed countries might incorporate racial/ethnic minority populations in future clinical trials and cancer researches with the overall objective of fomenting pharmacogenomics in clinical practice and public health policies.

Identification of miRNA-Mediated Subpathways as Prostate Cancer Biomarkers Based on Topological Inference in a Machine Learning Process Using Integrated Gene and miRNA Expression Data

Accurately identifying classification biomarkers for distinguishing between normal and cancer samples is challenging. Additionally, the reproducibility of single-molecule biomarkers is limited by the existence of heterogeneous patient subgroups and differences in the sequencing techniques used to collect patient data. In this study, we developed a method to identify robust biomarkers (i.e., miRNA-mediated subpathways) associated with prostate cancer based on normal prostate samples and cancer samples from a dataset from The Cancer Genome Atlas (TCGA; n = 546) and datasets from the Gene Expression Omnibus (GEO) database (n = 139 and n = 90, with the latter being a cell line dataset). We also obtained 10 other cancer datasets to evaluate the performance of the method. We propose a multi-omics data integration strategy for identifying classification biomarkers using a machine learning method that involves reassigning topological weights to the genes using a directed random walk (DRW)-based method. A global directed pathway network (GDPN) was constructed based on the significantly differentially expressed target genes of the significantly differentially expressed miRNAs, which allowed us to identify the robust biomarkers in the form of miRNA-mediated subpathways (miRNAs). The activity value of each miRNA-mediated subpathway was calculated by integrating multiple types of data, which included the expression of the miRNA and the miRNAs’ target genes and GDPN topological information. Finally, we identified the high-frequency miRNA-mediated subpathways involved in prostate cancer using a support vector machine (SVM) model. The results demonstrated that we obtained robust biomarkers of prostate cancer, which could classify prostate cancer and normal samples. Our method outperformed seven other methods, and many of the identified biomarkers were associated with known clinical treatments.

Signaling Pathways That Control Apoptosis in Prostate Cancer

Prostate cancer is the second most common malignancy and the fifth leading cancer-caused death in men worldwide. Therapies that target the androgen receptor axis induce apoptosis in normal prostates and provide temporary relief for advanced disease, yet prostate cancer that acquired androgen independence (so called castration-resistant prostate cancer, CRPC) invariably progresses to lethal disease. There is accumulating evidence that androgen receptor signaling do not regulate apoptosis and proliferation in prostate epithelial cells in a cell-autonomous fashion. Instead, androgen receptor activation in stroma compartments induces expression of unknown paracrine factors that maintain homeostasis of the prostate epithelium. This paradigm calls for new studies to identify paracrine factors and signaling pathways that control the survival of normal epithelial cells and to determine which apoptosis regulatory molecules are targeted by these pathways. This review summarizes the recent progress in understanding the mechanism of apoptosis induced by androgen ablation in prostate epithelial cells with emphasis on the roles of BCL-2 family proteins and "druggable" signaling pathways that control these proteins. A summary of the clinical trials of inhibitors of anti-apoptotic signaling pathways is also provided. Evidently, better knowledge of the apoptosis regulation in prostate epithelial cells is needed to understand mechanisms of androgen-independence and implement life-extending therapies for CRPC.

Non-Coding RNAs Set a New Phenotypic Frontier in Prostate Cancer Metastasis and Resistance

Prostate cancer (PCa) mortality remains a significant public health problem, as advanced disease has poor survivability due to the development of resistance in response to both standard and novel therapeutic interventions. Therapeutic resistance is a multifaceted problem involving the interplay of a number of biological mechanisms including genetic, signaling, and phenotypic alterations, compounded by the contributions of a tumor microenvironment that supports tumor growth, invasiveness, and metastasis. The androgen receptor (AR) is a primary regulator of prostate cell growth, response and maintenance, and the target of most standard PCa therapies designed to inhibit AR from interacting with androgens, its native ligands. As such, AR remains the main driver of therapeutic response in patients with metastatic castration-resistant prostate cancer (mCRPC). While androgen deprivation therapy (ADT), in combination with microtubule-targeting taxane chemotherapy, offers survival benefits in patients with mCRPC, therapeutic resistance invariably develops, leading to lethal disease. Understanding the mechanisms underlying resistance is critical to improving therapeutic outcomes and also to the development of biomarker signatures of predictive value. The interconversions between epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) navigate the prostate tumor therapeutic response, and provide a novel targeting platform in overcoming therapeutic resistance. Both microRNA (miRNA)- and long non-coding RNA (lncRNA)-mediated mechanisms have been associated with epigenetic changes in prostate cancer. This review discusses the current evidence-based knowledge of the role of the phenotypic transitions and novel molecular determinants (non-coding RNAs) as contributors to the emergence of therapeutic resistance and metastasis and their integrated predictive value in prostate cancer progression to advanced disease.

Genomic pan-cancer classification using image-based deep learning

Accurate cancer type classification based on genetic mutation can significantly facilitate cancer-related diagnosis. However, existing methods usually use feature selection combined with simple classifiers to quantify key mutated genes, resulting in poor classification performance. To circumvent this problem, a novel image-based deep learning strategy is employed to distinguish different types of cancer. Unlike conventional methods, we first convert gene mutation data containing single nucleotide polymorphisms, insertions and deletions into a genetic mutation map, and then apply the deep learning networks to classify different cancer types based on the mutation map. We outline these methods and present results obtained in training VGG-16, Inception-v3, ResNet-50 and Inception-ResNet-v2 neural networks to classify 36 types of cancer from 9047 patient samples. Our approach achieves overall higher accuracy (over 95%) compared with other widely adopted classification methods. Furthermore, we demonstrate the application of a Guided Grad-CAM visualization to generate heatmaps and identify the top-ranked tumor-type-specific genes and pathways. Experimental results on prostate and breast cancer demonstrate our method can be applied to various types of cancer. Powered by the deep learning, this approach can potentially provide a new solution for pan-cancer classification and cancer driver gene discovery. The source code and datasets supporting the study is available at https://github.com/yetaoyu/Genomic-pan-cancer-classification.

A Crosstalk Between Dual-Specific Phosphatases and Dual-Specific Protein Kinases Can Be A Potential Therapeutic Target for Anti-cancer Therapy

While protein tyrosine kinases (PTKs) play an initiative role in growth factor-mediated cellular processes, protein tyrosine phosphatases (PTPs) negatively regulates these processes, acting as tumor suppressors. Besides selective tyrosine dephosphorylation of PTKs via PTPs may affect oncogenic pathways during carcinogenesis. The PTP family contains a group of dual-specificity phosphatases (DUSPs) that regulate the activity of Mitogen-activated protein kinases (MAPKs), which are key effectors in the control of cell growth, proliferation and survival. Abnormal MAPK signaling is critical for initiation and progression stages of carcinogenesis. Since depletion of DUSP-MAPK phosphatases (MKPs) can reduce tumorigenicity, altering MAPK signaling by DUSP-MKP inhibitors could be a novel strategy in anti-cancer therapy. Moreover, Cdc25A is, a DUSP and a key regulator of the cell cycle, promotes cell cycle progression by dephosphorylating and activating cyclin-dependent kinases (CDK). Cdc25A-CDK pathway is a novel mechanism in carcinogenesis. Besides the mammalian target of rapamycin (mTOR) kinase inhibitors or mammalian target of rapamycin complex 1 (mTORC1) inhibition in combination with the dual phosphatidylinositol 3 kinase (PI3K)/mTOR or AKT kinase inhibitors are more effective in inhibiting the phosphorylation of eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) and cap-dependent translation. Dual targeting of the Akt and mTOR signaling pathways regulates cellular growth, proliferation and survival. Like the Cdc2-like kinases (CLK), dual-specific tyrosine phosphorylation-regulated kinases (DYRKs) are essential for the regulation of cell fate. The crosstalk between dual-specific phosphatases and dual- specific protein kinases is a novel drug target for anti-cancer therapy. Therefore, the focus of this chapter involves protein kinase modules, critical biochemical checkpoints of cancer therapy and the synergistic effects of protein kinases and anti-cancer molecules.

Evaluating and modulating TFEB in the control of autophagy: toward new treatments in CNS disorders

TFEB is a mammalian transcription factor that binds directly to the CLEAR consensus sequence (5'-GTCACGTGAC-3') present in the regulatory regions of genes inducing autophagosome formation, autophagosome-lysosome fusion, hydrolase enzyme expression, and lysosomal exocytosis. By modulating these activities, TFEB coordinates on-demand control over each cell's degradation pathway. Thus, a nuclear signaling pathway regulates cellular energy metabolism through TFEB. Our growing understanding of the role of TFEB and CLEAR in the promotion of healthy clearance together with in vitro and in vivo preclinical findings in various animal models of disease supports the conclusion that the pharmacological activation of TFEB could clear toxic proteins to treat both rare and common forms of neurodegenerative disease.

The hallmarks of ovarian cancer: proliferation and cell growth

Epithelial ovarian cancer (EOC) is a heterogeneous group of diseases with distinct biological and clinical behaviour. Despite the differences between them, the capability of tumour cells to continuously proliferate and avoid death is maintained among histotypes. This ability is the result of alterations at different levels, causing the deregulation of cell cycle and proliferative-related pathways. Even if the leading role is played by RB and TP53, changes in other molecular pathways are involved in the development of EOC. This ability can be exploited to generate in vitro and in vivo models resembling the conditions of tumour development in a patient. In vivo models, such as patient-derived xenografts (PDX) or genetically engineered mouse models (GEMM), represent a fundamental tool in the study of the molecular mechanisms implicated in each EOC biotype for testing new therapeutic approaches. Herein we describe the major proliferation-related pathways and its disruption found in EOC and how these features can be used to establish in vivo models for translational research.

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Epithelial ovarian cancer (EOC) molecular biotypes are defined by distinct biology and clinical behaviour.

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Sustained proliferation and resistance to cell death mechanisms characterised tumour cells.

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RB and TP53 tumour-suppressor genes are highly implicated in EOC pathogenesis.

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In vitro and in vivo models have a key role in the study of molecular mechanisms involved in EOC pathogenesis.

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Development of animal models that mimic disease features constitute essential tools for new drugs testing.

Mechanisms of Taxane Resistance

The taxane family of chemotherapy drugs has been used to treat a variety of mostly epithelial-derived tumors and remain the first-line treatment for some cancers. Despite the improved survival time and reduction of tumor size observed in some patients, many have no response to the drugs or develop resistance over time. Taxane resistance is multi-faceted and involves multiple pathways in proliferation, apoptosis, metabolism, and the transport of foreign substances. In this review, we dive deeper into hypothesized resistance mechanisms from research during the last decade, with a focus on the cancer types that use taxanes as first-line treatment but frequently develop resistance to them. Furthermore, we will discuss current clinical inhibitors and those yet to be approved that target key pathways or proteins and aim to reverse resistance in combination with taxanes or individually. Lastly, we will highlight taxane response biomarkers, specific genes with monitored expression and correlated with response to taxanes, mentioning those currently being used and those that should be adopted. The future directions of taxanes involve more personalized approaches to treatment by tailoring drug-inhibitor combinations or alternatives depending on levels of resistance biomarkers. We hope that this review will identify gaps in knowledge surrounding taxane resistance that future research or clinical trials can overcome.

Novel nanococktail of a dual PI3K/mTOR inhibitor and cabazitaxel for castration-resistant prostate cancer

Prognosis of castration-resistant prostate cancer (CRPC) carries is poor, and no effective therapeutic regimen is yet known. The phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway played a predominant role and may be a promising molecular target for CRPC. However, the toxicity of the dual PI3K inhibitors in clinical trials limits their clinical efficacy for CRPC. To solve this problem, we employed a highly integrated precision nanomedicine strategy to molecularly and physically target CRPC through synergistic effects, enhanced targeted drug delivery efficiency, and reduced unwanted side-effects. Gedatolisib (Ge), a potent inhibitor of PI3K/mTOR, was formulated into our disulfied-crosslinked micelle plateform (NanoGe), which exhibits excellent water solubility, small size (23.25±2 nm), excellent stability with redox stimulus-responsive disintegration, and preferential uptake at tumor sites. NanoGe improved the anti-neoplastic effect of free Ge by 53 times in PC-3M cells and 13 times in C4-2B cells though its enhanced uptake via caveolae- and clathrin-mediated endocytic pathways and the subsequent inhibition of the PI3K/mTOR pathway, resulting in Bax/Bcl-2 dependent apoptosis. In an animal xenograft model, NanoGe showed superior efficacy than free Ge, and synergized with nanoformulated cabazitaxel (NanoCa) as a nanococktail format to achieve a cure rate of 83%. Taken together, our results demonstrate the potency of NanoGe in combination with NanoCa is potent against prostate cancer.

Establishment and characterization of a docetaxel-resistant human prostate cancer cell line

The aim of the present study was to establish a novel docetaxel-resistant prostate cancer cell line and investigate its biological characteristics. The human prostate cell line, PC-3, was exposed to docetaxel, the concentrations of which were increased in a stepwise manner in the medium to select the drug-resistant cell line, PC-3/DTX. The morphological features were observed using inverted microscopy. The growth curves of PC-3 and PC-3/DTX cells were drawn to calculate the doubling time. Flow cytometry was performed to determine cell-cycle distribution. A 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide assay was performed to test the drug resistance of PC-3 and PC-3/DTX cells. Western blot analysis was conducted to determine the protein expression levels of the mammalian target of rapamycin (mTOR) signaling pathway, which may serve a role in regulating drug resistance in the two cell lines. PC-3/DTX cells exhibited changes in morphology, proliferation rate, doubling time and cell-cycle distributions, compared with PC-3 cells. PC-3/DTX cells were 10.9-fold resistant to docetaxel in comparison with PC-3 cells. The results showed that PC-3/DTX cells overexpressed Rictor and p-AKT(S473) proteins, which are specific subunits or downstream substrates of mTORC2. The new findings suggested that the mTORC2 signaling pathway may serve an important role in the regulation of docetaxel drug resistance of PC-3 cells. In conclusion, PC-3/DTX cells may be applied to study the resistance of anticancer drugs and to identify methods to overcome resistance.