PI3K/AKT/mTOR inhibitors for advanced or recurrent endometrial cancer

The Histomorphology to Molecular Transition: Exploring the Genomic Landscape of Poorly Differentiated Epithelial Endometrial Cancers

The peremptory need to circumvent challenges associated with poorly differentiated epithelial endometrial cancers (PDEECs), also known as Type II endometrial cancers (ECs), has prompted therapeutic interrogation of the prototypically intractable and most prevalent gynecological malignancy. PDEECs account for most endometrial cancer-related mortalities due to their aggressive nature, late-stage detection, and poor response to standard therapies. PDEECs are characterized by heterogeneous histopathological features and distinct molecular profiles, and they pose significant clinical challenges due to their propensity for rapid progression. Regardless of the complexities around PDEECs, they are still being administered inefficiently in the same manner as clinically indolent and readily curable type-I ECs. Currently, there are no targeted therapies for the treatment of PDEECs. The realization of the need for new treatment options has transformed our understanding of PDEECs by enabling more precise classification based on genomic profiling. The transition from a histopathological to a molecular classification has provided critical insights into the underlying genetic and epigenetic alterations in these malignancies. This review explores the genomic landscape of PDEECs, with a focus on identifying key molecular subtypes and associated genetic mutations that are prevalent in aggressive variants. Here, we discuss how molecular classification correlates with clinical outcomes and can refine diagnostic accuracy, predict patient prognosis, and inform therapeutic strategies. Deciphering the molecular underpinnings of PDEECs has led to advances in precision oncology and protracted therapeutic remissions for patients with these untamable malignancies.

Phosphocholine inhibits proliferation and reduces stemness of endometrial cancer cells by downregulating mTOR-c-Myc signaling

BACKGROUND

Endometrial cancer (EC) represents a serious health concern among women globally. Excessive activation of the protooncogene c-Myc (c-Myc) is associated with the proliferation and stemness of EC cells. Phosphocholine (PC), which is synthesized by choline kinase alpha (CHKA) catalysis, is upregulated in EC tumor tissues. The present study aimed to investigate the effect of PC accumulation on EC cells and clarify the relationship between PC accumulation and c-Myc activity in EC.

METHODS

The c-Myc and CHKA expression in EC tumor tissues were examined using immunohistochemistry. Cell Counting Kit-8 assay, colony formation assay, flow cytometry, western blotting, BrdU staining, and tumorsphere formation assay were used to assess the effect of PC accumulation on EC cells. The mechanism by which PC accumulation inhibits c-Myc was evaluated using RNA-sequencing. Patient-derived organoid (PDO) models were utilised to explore the preclinical efficacy of PC against EC cells.

RESULTS

PC accumulation suppressed EC cell proliferation and stemness by inhibiting the activation of the mammalian target of rapamycin (mTOR)-c-Myc signaling. PC accumulation promoted excessive reactive oxygen species production, which reduced the expression of GTPase HRAS. This, in turn, inhibited the mTOR-c-Myc axis and induced EC cell apoptosis. Finally, PC impeded proliferation and downregulated the expression of the mTOR-MYC signaling in EC PDO models.

CONCLUSIONS

PC accumulation impairs the proliferation ability and stem cell characteristics of EC cells by inhibiting the activated mTOR-c-Myc axis, potentially offering a promising strategy to enhance the efficacy of EC clinical therapy through the promotion of PC accumulation in tumor cells.

mTOR inhibitors as potential therapeutics for endometriosis: a narrative review

Mammalian target of rapamycin (mTOR) inhibitors have been used clinically as anticancer and immunosuppressive agents for over 20 years, demonstrating their safety after long-term administration. These inhibitors exhibit various effects, including inhibition of cell proliferation, interaction with the oestrogen and progesterone pathways, immunosuppression, regulation of angiogenesis, and control of autophagy. We evaluated the potential of mTOR inhibitors as therapeutic agents for endometriosis, examined the secondary benefits related to reproductive function, and assessed how their side effects can be managed. We conducted a thorough review of publications on the role of the mTOR pathway and the effectiveness of mTOR inhibitors in endometriosis patients. These results indicate that the mTOR pathway is activated in endometriosis. Additionally, mTOR inhibitors have shown efficacy as monotherapies for endometriosis. They may alleviate resistance to hormonal therapy in endometriosis, suggesting a potential synergistic effect when used in combination with hormonal therapy. The potential reproductive benefits of mTOR inhibitors include decreased miscarriage rates, improved implantation, and prevention of age-related follicular loss and ovarian hyperstimulation syndrome. Activation of the mTOR pathway has also been implicated in the malignant transformation of endometriosis. Preclinical studies suggest that the dosage of mTOR inhibitors needed for treating endometriosis may be lower than that required for anticancer or immunosuppressive therapy, potentially reducing dosage-dependent side effects. In conclusion, while mTOR inhibitors, which allow for pregnancy during oral administration, show potential for clinical use in all stages of endometriosis, current evidence is limited to preclinical studies, and further research is needed to confirm clinical effectiveness.

Tanshinone IIA Loaded Inhaled Polymer Nanoparticles Alleviate Established Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a fatal respiratory disease characterized by chronic, progressive scarring of the lung parenchyma, leading to an irreversible decline in lung function. Apart from supportive care, there is currently no specific treatment available to reverse the disease. Based on the fact that tanshinone IIA (TAN) had an effect on protecting against TGF-β1-induced fibrosis through the inhibition of Smad and non-Smad signal pathways to avoid myofibroblasts activation, this study reported the development of the inhalable tanshinone IIA-loaded chitosan-oligosaccharides-coated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (CPN@TAN) for enhancing the pulmonary delivery of tanshinone IIA to treat pulmonary fibrosis. The CPN@TAN with a size of 206.5 nm exhibited excellent in vitro aerosol delivery characteristics, featuring a mass median aerodynamic diameter (MMAD) of 3.967 ± 0.025 μm and a fine particle fraction (FPF) of 70.516 ± 0.929%. Moreover, the nanoparticles showed good stability during atomization and enhanced the mucosal penetration capabilities. The results of confocal spectroscopy confirmed the potential of the nanoparticles as carriers that facilitated the uptake of drugs by NIH3T3, A549, and MH-S cells. Additionally, the nanoparticles demonstrated good in vitro biocompatibility. In a mouse model of bleomycin-induced pulmonary fibrosis, noninvasive inhalation of aerosol CPN@TAN greatly suppressed collagen formation and facilitated re-epithelialization of the destroyed alveolar epithelium without causing systemic toxicity compared with intravenous administration. Consequently, our noninvasive inhalation drug delivery technology based on polymers may represent a promising paradigm and open the door to overcoming the difficulties associated with managing pulmonary fibrosis.

Clinical utility of comprehensive liquid molecular profiling in patients with advanced endometrial cancer

BACKGROUND

Molecular characterization has significantly improved the management of advanced endometrial cancer (EC). It distinguishes four molecular subclasses associated with prognosis and personalized therapeutic strategies. This study assesses the clinical utility of cell-free DNA (cfDNA) profiling in EC to identify targetable alterations.

METHODS

Women with metastatic or recurrent EC were prospectively recruited within the framework of the STING trial (NCT04932525), during which cfDNA was analyzed. Genomic alterations were identified with the FoundationOne CDx assay. Each molecular report underwent review by a molecular tumor board. Alterations were categorized via the European Society of Medical Oncology Scale for Clinical Actionability of Molecular Targets (ESCAT).

RESULTS

A total of 61 patients were enrolled. The median age was 66.9 years, with 43% presenting frontline metastatic disease. All histologic subgroups were represented. Notably, 89% of patients yielded informative cfDNA analysis. Six tumors were classified with deficient mismatch repair/microsatellite instability (11%) and 37 as TP53 gene mutant (67%), and 12 had nonspecific molecular profiles (22%). Molecular classification based on liquid biopsy showed 87.5% accuracy in correlating with tissue results. Moreover, 65% of cases exhibited ≥1 actionable alteration, including 25% ESCAT I alterations and 13% ESCAT II alterations. Consequently, 16% of patients received a molecularly matched therapy, and presented with a 56% response rate and median progression-free survival of 7.7 months.

CONCLUSIONS

cfDNA sequencing in EC is a feasible approach that produces informative results in 89% of cases and accurately categorizes patients into the main molecular subclasses. It also reveals multiple actionable alterations, which offers the potential for personalized therapeutic strategies.

Copper homeostasis and cuproptosis in gynecological cancers

Copper (Cu) is an essential trace element involved in a variety of biological processes, such as antioxidant defense, mitochondrial respiration, and bio-compound synthesis. In recent years, a novel theory called cuproptosis has emerged to explain how Cu induces programmed cell death. Cu targets lipoylated enzymes in the tricarboxylic acid cycle and subsequently triggers the oligomerization of lipoylated dihydrolipoamide S-acetyltransferase, leading to the loss of Fe-S clusters and induction of heat shock protein 70. Gynecological malignancies including cervical cancer, ovarian cancer and uterine corpus endometrial carcinoma significantly impact women's quality of life and even pose a threat to their lives. Excessive Cu can promote cancer progression by enhancing tumor growth, proliferation, angiogenesis and metastasis through multiple signaling pathways. However, there are few studies investigating gynecological cancers in relation to cuproptosis. Therefore, this review discusses Cu homeostasis and cuproptosis while exploring the potential use of cuproptosis for prognosis prediction as well as its implications in the progression and treatment of gynecological cancers. Additionally, we explore the application of Cu ionophore therapy in treating gynecological malignancies.

MicroRNAs targeted mTOR as therapeutic agents to improve radiotherapy outcome

MicroRNAs (miRNAs) are small RNA molecules that regulate genes and are involved in various biological processes, including cancer development. Researchers have been exploring the potential of miRNAs as therapeutic agents in cancer treatment. Specifically, targeting the mammalian target of the rapamycin (mTOR) pathway with miRNAs has shown promise in improving the effectiveness of radiotherapy (RT), a common cancer treatment. This review provides an overview of the current understanding of miRNAs targeting mTOR as therapeutic agents to enhance RT outcomes in cancer patients. It emphasizes the importance of understanding the specific miRNAs that target mTOR and their impact on radiosensitivity for personalized cancer treatment approaches. The review also discusses the role of mTOR in cell homeostasis, cell proliferation, and immune response, as well as its association with oncogenesis. It highlights the different ways in which miRNAs can potentially affect the mTOR pathway and their implications in immune-related diseases. Preclinical findings suggest that combining mTOR modulators with RT can inhibit tumor growth through anti-angiogenic and anti-vascular effects, but further research and clinical trials are needed to validate the efficacy and safety of using miRNAs targeting mTOR as therapeutic agents in combination with RT. Overall, this review provides a comprehensive understanding of the potential of miRNAs targeting mTOR to enhance RT efficacy in cancer treatment and emphasizes the need for further research to translate these findings into improved clinical outcomes.

Unsolved Issues in the Integrated Histo-Molecular Classification of Endometrial Carcinoma and Therapeutic Implications

Endometrial carcinoma (EC) is the most frequent gynecological cancer, with an increasing incidence and mortality in recent times. The last decade has represented a true revolution with the development of the integrated histo-molecular classification of EC, which allows for the stratification of patients with morphologically indistinguishable disease into groups with different prognoses. Particularly, the POLE-mutated subgroup exhibits outstanding survival. Nevertheless, the indiscriminate application of molecular classification appears premature. Its prognostic significance has been proven mainly in endometrioid EC, the most common histotype, but it has yet to be convincingly confirmed in the other minor histotypes, which indeed account for a relevant proportion of EC mortality. Moreover, its daily use both requires a mindful pathologist who is able to correctly evaluate and unambiguously report immunohistochemical staining used as a surrogated diagnostic tool and is hampered by the unavailability of POLE mutation analysis. Further molecular characterization of ECs is needed to allow for the identification of better-tailored therapies in different settings, as well as the safe avoidance of surgery for fertility preservation. Hopefully, the numerous ongoing clinical trials in the adjuvant and metastatic settings of EC will likely produce evidence to refine the histo-molecular classification and therapeutic guidelines. Our review aims to retrace the origin and evolution of the molecular classification for EC, reveal its strengths and limitations, show clinical relevance, and uncover the desired future developments.

Molecular characterization as new driver in prognostic signatures and therapeutic strategies for endometrial cancer

Endometrial cancer (EC) incidence and mortality rates have been increasing, particularly among young females. Although more than 90% of ECs are sporadic, 5-10% are hereditary, a majority of which occurs within Hereditary Non-Polyposis Colorectal Cancer syndrome (HNPCC) or Lynch syndrome. The traditional histopathological classification differentiates EC between two main groups: type I (or endometrioid) and type II (including all other histopathological subtypes). However, this classification lacks reproducibility and does not account for the emerging molecular heterogeneity. In 2013, The Cancer Genome Atlas (TCGA) project proposed EC molecular classification defining four groups with different prognostic and predictive values and the current international guidelines are progressively establishing EC risk stratification and treatment based on both histopathological and molecular criteria. Our manuscript aims to summarize the current state of EC molecular characterizations, including germline alterations at the basis of hereditary EC predisposition, to discuss their clinical utility as prognostic and predictive markers.

Transcriptome analysis of an AKT inhibitor-resistant endometrial cancer cell line

BACKGROUND

Drug resistance in endometrial cancer (EC) is a serious problem and a barrier to improving prognosis. The PI3K/AKT/mTOR pathway is highly activated in EC and can serve as a potential therapeutic target. Inhibitors against AKT have been developed, but resistance to these inhibitors is a concern. This study aimed to establish AKT inhibitor resistant cell lines and identify differentially expressed genes (DEGs) between parental and AKT inhibitor resistant cell lines to understand the mechanism of drug resistance to AKT inhibitors in EC.

METHODS

The sensitivity of eight EC cell lines to AKT inhibitor was analyzed. One of them was used to establish a drug-resistant cell line. DEGs were examined using RNA sequencing (RNA-seq). Furthermore, DEGs were comprehensively analyzed to identify hub genes. Hub genes were evaluated using quantitative real-time polymerase chain reaction.

RESULTS

RNA-seq identified 617 DEGs. Hub genes were selected using bioinformatics analysis. The top 10 hub genes were TNF, CDH1, CCND1, COL1A1, CDH2, ICAM1, CAV1, THBS1, NCAM1, and CDKN2A. Relative mRNA expression was significantly upregulated for TNF, CDH1, CCND1, THBS1, p16INK4a, and p14ARF and significantly downregulated for CDH2, ICAM1, and NCAM1 in borussertib-resistant EC cell line.

CONCLUSIONS

Drug resistance to AKT inhibitors may depend on genes related to cell adhesion-mediated resistance and transforming growth factor β signaling.

Soluble guanylyl cyclase beta1 subunit targets epithelial-to-mesenchymal transition and downregulates Akt pathway in human endometrial and cervical cancer cells

Endometrial and cervical cancer are among the most frequently diagnosed malignancies globally. Nitric oxide receptor-soluble guanylyl cyclase (sGC) is a heterodimeric enzyme composed of two subunits, α1 and β1. Previously we showed that sGCα1 subunit promotes cell survival, proliferation, and migration, but the role of sGCβ1 subunit has not been addressed. The aim of the present work was to study the impact of sGCβ1 restoration in proliferation, survival, migration, and cell signaling in endometrial and cervical cancer cells. We found that sGCβ1 transcript levels are reduced in endometrial and cervical tumors vs normal tissues. We confirmed nuclear enrichment of sGCβ1, unlike sGCα1. Overexpression of sGCβ1 reduced cell viability and augmented apoptotic index. Cell migration and invasion were also negatively affected. All these sGCβ1-driven effects were independent of sGC enzymatic activity. sGCβ1 reduced the expression of epithelial-to-mesenchymal transition factors such as N-cadherin and β-catenin and increased the expression of E-cadherin. sGCβ1 impacted signaling in endometrial and cervical cancer cells through significant downregulation of Akt pathway affecting some of its main targets such as GSK-3β and c-Raf. Our results show for the first time that sGCβ1 exerts several antiproliferative actions in ECC-1 and HeLa cell lines by targeting key regulatory pathways.

Ipatasertib exhibits anti‑tumorigenic effects and enhances sensitivity to paclitaxel in endometrial cancer in vitro and in vivo

Endometrial cancer is the most common gynecologic cancer and one of the only cancers for which incidence and mortality is steadily increasing. Although curable with surgery in the early stages, endometrial cancer presents a significant clinical challenge in the metastatic and recurrent setting with few novel treatment strategies emerging in the past fifty years. Ipatasertib (IPAT) is an orally bioavailable pan‑AKT inhibitor, which targets all three AKT isoforms and has demonstrated anti‑tumor activity in pre‑clinical models, with clinical trials emerging for many cancer types. In the present study, the MTT assay was employed to evaluate the therapeutic efficacy of IPAT or IPAT in combination with paclitaxel (PTX) in endometrial cancer cell lines and primary cultures of endometrial cancer. The effect of IPAT and PTX on the growth of endometrial tumors was evaluated in a transgenic mouse model of endometrial cancer. Apoptosis was assessed using cleaved caspase assays and cellular stress was assessed using ROS, JC1 and tetramethylrhodamine ethyl ester assays. The protein expression levels of markers of apoptosis and cellular stress, and DNA damage were evaluated using western blotting and immunohistochemistry. IPAT significantly inhibited cell proliferation, caused cell cycle G1 phase arrest, and induced cellular stress and mitochondrial apoptosis in a dose dependent manner in human endometrial cancer cell lines. Combined treatment with low doses of IPAT and PTX led to synergistic inhibition of cell proliferation and induction of cleaved caspase 3 activity in the human endometrial cancer cell lines and the primary cultures. Furthermore, IPAT effectively reduced tumor growth, accompanied by decreased protein expression levels of Ki67 and phosphorylation of S6 in the Lkb1fl/flp53fl/fl mouse model of endometrioid endometrial cancer. The combination of IPAT and PTX resulted in increased expression of phosphorylated‑H2AX and KIF14, markers of DNA damage and microtubule dysfunction respectively, as compared with IPAT alone, PTX alone or placebo‑treated mice. The results of the present study provide a biological rationale to evaluate IPAT and the combination of IPAT and PTX in future clinical trials for endometrial cancer.

Pembrolizumab plus lenvatinib in advanced endometrial cancer: case report and systematic review of lung toxicity

Background

The optimal strategy for the treatment of recurrent and/or advanced endometrial cancer is still undefined. Recently, despite the lack of any predictive biomarker, the combination of pembrolizumab with lenvatinib has improved survival outcomes. We here report the long-term management of lung toxicity in a patient with endometrial cancer, and we critically review the current therapeutic options for this disease.

Results

A patient with heavily pretreated endometrial cancer took pembrolizumab plus lenvatinib for 1 year, achieving a persistent partial response with a time to treatment failure of 18 months, despite relevant lung toxicity that did not affect the remarkable overall clinical benefit. A systematic review of this combination underlines the efficacy outcome despite toxicity. Interestingly, the literature review on lung toxicity suggested the role of anti-angiogenetic agents in the pathogenesis of lung cavitation, probably related to direct treatment activity, and disclosed a potential radiological sign predictive of the activity of anti-angiogenetic agents.

Conclusion

We underline the efficacy of pembrolizumab plus lenvatinib in the current treatment landscape of endometrial cancer, underscoring the relevance of a correct management of toxicity.

Genomic determinants in advanced endometrial cancer patients with sustained response to hormonal therapy- case series and review of literature

The incidence of endometrial cancer is increasing, however treatment options for advanced disease are limited. Hormonal therapy has demonstrated positive outcomes for Stage IV EC. Next generation sequencing (NGS) has increased our understanding of molecular mechanisms driving EC. In this case series, we selected six patients at our institution with Stage IV, hormone receptor positive, endometrial cancer currently being treated with hormonal therapy. All patients achieved SD for at least ≥ 1.5 years. We studied NGS data on all six patients to assess for any common genomic marker which could predict the SD of at least 1.5 years achieved in this group. Institutional Review Board (IRB) approval was obtained from Staten Island University Hospital and Northwell Health, New York. PTEN, PIK3CA, PIK3R1, and ARID1A mutations were found in 83%, 67% 50%, and 67% of patients respectively. TP53 and FGFR2 were both found in 50% of patients. All patients were positive for estrogen and/or progesterone receptor (ER+ and/or PR+). We did not find any one common mutation that could have predicted the observed response (or SD of ≥1.5 years) to hormone therapy. However, our data reflects the prevalence of various mutations reported in literature: (1) Hormone Receptor status is a positive prognostic indicator (2) PTEN/PIK3CA mutations can occur concurrently in EC (3) ARID1A coexists with PTEN (4) FGFR and PTEN pathways may be interlinked. We suggest NGS be employed frequently in patients with endometrial cancer to identify targetable mutations. Additional larger studies are needed to characterize the interplay between mutations.

MLLT11-TRIL complex promotes the progression of endometrial cancer through PI3K/AKT/mTOR signaling pathway

Endometrial cancer (EC) is a gynecological malignant tumor characterized by high incidence. EC occurrence and development are regulated by numerous molecules and signal pathways. There is a need to explore key regulatory molecules to identify potential therapeutic targets to reduce the incidence of EC. Treatment by targeting a single molecule is characterized by poor efficacy owing to the development of resistance and significant side effects. The current study explored potential candidates in EC by integrating bioinformatics analysis and in vivo and in vitro experimental validation to circumvent the limitation of low efficacy of currently used molecules. Molecular dynamics simulations provide details at the molecular level of intermolecular regulation. In the current study, MLLT11 and TRIL were identified as important regulatory molecules in EC. The two molecules formed a heteromultimer by binding to AKT protein, which induced its phosphorylation of threonine at position 308. Ultimately, the complex stimulates PI3K/AKT/mTOR signaling pathway, a pivotal pathway in tumors. The findings of the current study show a novel complex, MLLT11-TRIL, which can act as AKT protein agonist, thus inducing activity of PI3K/AKT/mTOR signaling pathway. Targeting MLLT11 and TRIL simultaneously, or blocking the formation of the MLLT11-TRIL complex, can abrogate progression of EC.

Pentamidine inhibits proliferation, migration and invasion in endometrial cancer via the PI3K/AKT signaling pathway

BACKGROUND

Pentamidine has been reported to have many pharmacological effects including anti- protozoal, anti-inflammatory, and anti-tumor activities. The aim of this study is to investigate the potential therapeutic role of Pentamidine and molecular mechanisms of Pentamidine on PI3K/AKT signaling pathway underlying the anti-tumor properties in endometrial cancer.

METHODS

Our study was carried out in the central laboratory of Harbin Medical University from 2019 to 2021. Human endometrial cancer cell lines Ishikawa and HEC-1A were treated with Pentamidine. The proliferation ability of cells was investigated by MTS and colony formation assays. The cell cycle distribution was detected by flow cytometry. Cell migration and invasion were analyzed by using the wound healing assay and Transwell assay. Western blotting was performed to measure the levels of AKT, p-AKT, MMP-2, and MMP-9.

RESULTS

Our results revealed that treatment of Pentamidine inhibited proliferation, migration and invasion of Ishikawa and HEC-1A endometrial cancer cells. Mechanistic investigation showed that Pentamidine inhibited PI3K/AKT signaling pathway and also reduced the expression of MMP-2 and MMP-9. In addition, co-treatment with PI3K kinase inhibitor LY294002 and Pentamidine leaded to increased repression of cell viability and the protein expression of p-AKT in Ishikawa cells.

CONCLUSIONS

Pentamidine suppresses PI3K/AKT signaling pathway, and inhibits proliferation, migration and invasion of EC cells. These findings suggested that Pentamidine might be a potential candidate for treating EC through PI3K/AKT pathway.

Tocotrienol-Rich Fractions Offer Potential to Suppress Pulmonary Fibrosis Progression

Although pulmonary fibrosis (PF) is considered a rare disease, the incidence thereof has increased steadily in recent years, while a safe and effective cure remains beyond reach. In this study, the potential of tocotrienol-rich fractions (TRF) and carotene to alleviate PF was explored. PF was induced in Sprague-Dawley rats via a single intratracheal bleomycin (BLM) (5 mg/kg) instillation. These rats were subsequently treated with TRF, carotene, pirfenidone (Pir) and nintedanib (Nin) for 28 days via gavage administration, whereafter histopathological performance, biochemical functions and molecular alterations were studied in the lung tissues. Our results showed that TRF, carotene, Nin and Pir all ameliorated PF by reducing inflammation and resisting oxidative stress to varying degrees. The related mechanisms involved the TGF-β1/Smad, PI3K/Akt and NF-κB signaling pathways. Ultimately, our findings revealed that, when combined with TRF, the therapeutic effects of Nin and Pir on PF were enhanced, indicating that TRF may, indeed, provide promising potential for use in combination therapy in the treatment of PF.

Anticancer effects of ABTL0812, a clinical stage drug inducer of autophagy-mediated cancer cell death, in glioblastoma models

Background

Glioblastoma multiforme (GBM) is the most malignant adult brain tumor. Current standard of care treatments have very limited efficacy, being the patients´ overall survival 14 months and the 2-year survival rate less than 10%. Therefore, the treatment of GBM is an urgent unmet clinical need.

Methods

The aim of this study was to investigate in vitro and in vivo the potential of ABTL0812, an oral anticancer compound currently in phase II clinical stage, as a novel therapy for GBM.

Results

We showed that ABTL0812 inhibits cell proliferation in a wide panel of GBM cell lines and patient-derived glioblastoma stem cells (GSCs) with half maximal inhibitory concentrations (IC50s) ranging from 15.2 µM to 46.9 µM. Additionally, ABTL0812 decreased GSCs neurosphere formation. GBM cells aggressiveness is associated with a trans-differentiation process towards a less differentiated phenotype known as proneural to mesenchymal transition (PMT). ABTL0812 was shown to revert PMT and induce cell differentiation to a less malignant phenotype in GBM cell lines and GSCs, and consequently reduced cell invasion. As previously shown in other cancer types, we demonstrated that the molecular mechanism of action of ABTL0812 in glioblastoma involves the inhibition of Akt/mTORC1 axis by overexpression of TRIB3, and the activation of endoplasmic reticulum (ER) stress/unfolded protein response (UPR). Both actions converge to induce autophagy-mediated cell death. ABTL0812 anticancer efficacy was studied in vivo using subcutaneous and orthotopic intra-brain xenograft tumor models. We demonstrated that ABTL0812 impairs tumor growth and increases disease-free survival and overall survival of mice. Furthermore, the histological analysis of tumors indicated that ABTL0812 decreases angiogenesis. Finally, we investigated the combination of ABTL0812 with the standard of care treatments for GBM radiotherapy and temozolomide in an orthotopic model, detecting that ABTL0812 potentiates the efficacy of both treatments and that the strongest effect is obtained with the triple combination of ABTL0812+radiotherapy+temozolomide.

Conclusions

Overall, the present study demonstrated the anticancer efficacy of ABTL0812 as single agent and in combination with the GBM standard of care treatments in models of glioblastoma and supports the clinical investigation of ABTL0812 as a potential novel therapy for this aggressive brain tumor type.

Discovering biomarkers for hormone-dependent tumors: in silico study on signaling pathways implicated in cell cycle and cytoskeleton regulation

Malignancies dependent on hormone homeostasis include breast, ovary, cervical, prostate, testis and uterine tumors. Hormones are involved in signal transduction which orchestrate processes, such as apoptosis, proliferation, cell cycle or cytoskeleton organization. Currently, there is a need for novel biomarkers which would help to diagnose cancers efficiently. In this study, the genes implicated in signaling that is important in hormone-sensitive carcinogenesis were investigated regarding their prognostic significance. Data of seven cancer cohorts were collected from FireBrowse. 54 gene sets implicated in specific pathways were browsed through MSig database. Profiling was assessed via Monocle3, while gene ontology through PANTHER. For confirmation, correlation analysis was performed using WGCNA. Protein-protein networks were visualized via Cytoscape and impact of genes on survival, as well as cell cycle or cytoskeleton-related prognostic signatures, was tested. Several differences in expression profile were identified, some of them allowed to distinguish histology. Functional annotation revealed that various regulation of cell cycle, adhesion, migration, apoptosis and angiogenesis underlie these differences. Clinical traits, such as histological type or cancer staging, were found during evaluation of module-trait relationships. Of modules, the TopHubs (COL6A3, TNR, GTF2A1, NKX3-1) interacted directly with, e.g., PDGFB, ITGA10, SP1 or AKT3. Among TopHubs and interacting proteins, many showed an impact on hazard ratio and affected the cell cycle or cytoskeleton-related prognostic signatures, e.g., COL1A1 or PDGFB. In conclusion, this study laid the foundation for further hormone-sensitive carcinogenesis research through identification of genes which prove that crosstalk between cell cycle and cytoskeleton exists, opening avenues for future therapeutic strategies.

Role of HIF-1α/ERRα in Enhancing Cancer Cell Metabolism and Promoting Resistance of Endometrial Cancer Cells to Pyroptosis

Oxygen is critical to energy metabolism, and tumors are often characterized by a hypoxic microenvironment. Owing to the high metabolic energy demand of malignant tumor cells, their survival is promoted by metabolic reprogramming in the hypoxic microenvironment, which can confer tumor cell resistance to pyroptosis. Pyroptosis resistance can inhibit anti-tumor immunity and promote the development of malignant tumors. Hypoxia inducible factor-1α (HIF-1α) is a key regulator of metabolic reprogramming in tumor cells, and estrogen-related receptor α (ERRα) plays a key role in regulating cellular energy metabolism. Therefore, the close interaction between HIF-1α and ERRα influences the metabolic and functional changes in cancer cells. In this review, we summarize the reprogramming of tumor metabolism involving HIF-1α/ERRα. We review our understanding of the role of HIF-1α/ERRα in promoting tumor growth adaptation and pyroptosis resistance, emphasize its key role in energy homeostasis, and explore the regulation of HIF-1α/ERRα in preventing and/or treating endometrial carcinoma patients. This review provides a new perspective for the study of the molecular mechanisms of metabolic changes in tumor progression.

Ipatasertib, an oral AKT inhibitor, inhibits cell proliferation and migration, and induces apoptosis in serous endometrial cancer

Ipatasertib (IPAT) is an orally administered, selective protein kinase B (AKT) inhibitor with promising data in solid tumors in both pre-clinical studies and clinical trials. Given that the PI3K/AKT/mTOR pathway is frequently dysregulated in uterine serous carcinoma (USC), we aimed to explore the functional impact of IPAT on anti-tumorigenic activity in USC cell lines and primary cultures of USC. We found that IPAT significantly inhibited cell proliferation and colony formation in a dose-dependent manner in USC cells. Induction of cell cycle arrest and apoptosis was observed in IPAT-treated ARK1 and SPEC-2 cells. Treatment with IPAT resulted in reduced adhesion and invasion of both cell lines with a concomitant decrease in the expression of Snail, Slug, and N-Cadherin. Compared with single-drug treatment, the combination of IPAT and paclitaxel synergistically reduced cell proliferation and increased the activity of cleaved caspase 3 in both cell lines. Additionally, IPAT inhibited growth in four of five primary USC cultures, and three of five primary cultures also exhibited synergistic growth inhibition when paclitaxel and IPAT were combined. These results support that IPAT appears to be a promising targeted agent in the treatment of USC.

Regulatory mechanism of miR-20a-5p expression in Cancer

MicroRNAs(miRNAs) are non-coding single-stranded RNA molecules encoded by endogenous genes with a length of about 22 nucleotides. The dysregulation of miRNAs has been proven to be one of the vital causes of cancer, which makes them a biomarker for cancer diagnosis and prognosis. Compared with surgery and chemotherapy, nucleic acid therapy targeting specific miRNAs is a promising candidate for cancer treatment. miR-20a-5p plays an anticancer role in high-incidence human cancers such as cervical cancer, breast cancer and leukemia, which is of great importance in the diagnosis of cancers. The up-regulation and down-regulation of miR-20a-5p offers a possible breakthrough for the treatment of cancers. In this paper, we aim to investigate the functional significance of miR-20a-5p in different cancers, reviewing the expression differences of miR-20a-5p in cancer, while systematically summarizing the changes of circRNA-miR-20a-5p networks, and probe how it promotes messenger RNA (mRNA) degradation or inhibits mRNA translation to regulate downstream gene expression. We've also summarized the biogenesis mechanism of miRNAs, and emphasized its role in cell proliferation, cell apoptosis and cell migration. On this basis, we believe that miR-20a-5p is a promising and effective marker for cancer diagnosis, prognosis and treatment.

Potential “Therapeutic” Effects of Tocotrienol-Rich Fraction (TRF) and Carotene “Against” Bleomycin-Induced Pulmonary Fibrosis in Rats via TGF-β/Smad, PI3K/Akt/mTOR and NF-κB Signaling Pathways

Background: Pulmonary fibrosis (PF) is a chronic, progressive, and, ultimately, terminal interstitial disease caused by a variety of factors, ranging from genetics, bacterial, and viral infections, to drugs and other influences. Varying degrees of PF and its rapid progress have been widely reported in post-COVID-19 patients and there is consequently an urgent need to develop an appropriate, cost-effective approach for the prevention and management of PF. Aim: The potential “therapeutic” effect of the tocotrienol-rich fraction (TRF) and carotene against bleomycin (BLM)-induced lung fibrosis was investigated in rats via the modulation of TGF-β/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Design/Methods: Lung fibrosis was induced in Sprague-Dawley rats by a single intratracheal BLM (5 mg/kg) injection. These rats were subsequently treated with TRF (50, 100, and 200 mg/kg body wt/day), carotene (10 mg/kg body wt/day), or a combination of TRF (200 mg/kg body wt/day) and carotene (10 mg/kg body wt/day) for 28 days by gavage administration. A group of normal rats was provided with saline as a substitute for BLM as the control. Lung function and biochemical, histopathological, and molecular alterations were studied in the lung tissues. Results: Both the TRF and carotene treatments were found to significantly restore the BLM-induced alterations in anti-inflammatory and antioxidant functions. The treatments appeared to show pneumoprotective effects through the upregulation of antioxidant status, downregulation of MMP-7 and inflammatory cytokine expressions, and reduction in collagen accumulation (hydroxyproline). We demonstrated that TRF and carotene ameliorate BLM-induced lung injuries through the inhibition of apoptosis, the induction of TGF-β1/Smad, PI3K/Akt/mTOR, and NF-κB signaling pathways. Furthermore, the increased expression levels were shown to be significantly and dose-dependently downregulated by TRF (50, 100, and 200 mg/kg body wt/day) treatment in high probability. The histopathological findings further confirmed that the TRF and carotene treatments had significantly attenuated the BLM-induced lung injury in rats. Conclusion: The results of this study clearly indicate the ability of TRF and carotene to restore the antioxidant system and to inhibit proinflammatory cytokines. These findings, thus, revealed the potential of TRF and carotene as preventive candidates for the treatment of PF in the future.

Adipocytokines and disease progression in endometrial cancer: a systematic review

The objective of the study was to document the effect of adipocytokines on endometrial cancer progression. A search of the databases CINAHL, Medline, PubMed, Cochrane, Web of Science, Embase and Google Scholar was performed for English language articles from January 2000 to December 2020 using the keywords: (Endometrial cancer) AND (progression OR metastasis) AND (adipocytokine OR adiponectin OR leptin OR visfatin OR IL-6 OR TNF-α OR adipokine OR cytokine). Forty-nine studies on adipocytokines have been included in this review. Adiponectin has been linked with anti-proliferative and anti-metastatic effects on endometrial cancer cells and is associated with a better prognosis. Leptin, visfatin and resistin are linked to the stimulation of endometrial cancer growth, proliferation, invasion and metastasis and are associated with worse prognosis or with a higher grade/stage of endometrial cancer. IL-6, Il-11, IL-31, IL-33, TNF-α, TGF-β1, SDF-1 and CXCR are involved in endometrial cancer cell growth and metastasis or involved in epithelial mesenchymal transformation (EMT) or associated with advanced disease. Adipocytokines have been found to directly impact endometrial cancer cell proliferation, invasion and migration. These molecules and their signalling pathways may be used to determine prognosis and course of the disease and may also be exploited as potential targets for cancer treatment and prevention of progression.

The biochemical and clinical implications of phosphatase and tensin homolog deleted on chromosome ten in different cancers

Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is widely known as a tumor suppressor gene. It is located on chromosome 10q23 with 200 kb, and has dual activity of both protein and lipid phosphatase. In addition, as a targeted gene in multiple pathways, PTEN has a variety of physiological activities, such as those regulating the cell cycle, inducing cell apoptosis, and inhibiting cell invasion, etc. The PTEN gene have been identified in many kinds of cancers due to its mutations, deletions and inactivation, such as lung cancer, liver cancer, and breast cancer, and they are closely connected with the genesis and progression of cancers. To a large extent, the tumor suppressive function of PTEN is realized through its inhibition of the PI3K/AKT signaling pathway which controls cells apoptosis and development. In addition, PTEN loss has been associated with the prognosis of many cancers, such as lung cancer, liver cancer, and breast cancer. PTEN gene is related to many cancers and their pathological development. On the basis of a large number of related studies, this study describes in detail the structure, regulation, function and classical signal pathways of PTEN, as well as the relationship between various tumors related to PTEN. In addition, some drug studies targeting PTEN/PI3K/AKT/mTOR are also introduced in order to provide some directions for experimental research and clinical treatment of tumors.

Metformin and arsenic trioxide synergize to trigger Parkin/pink1-dependent mitophagic cell death in human cervical cancer HeLa cells

Mitochondria are involved in various biological processes including intracellular homeostasis, proliferation, senescence, and death, and mitochondrial mitophagy is closely related to the development and regression of malignant tumors. Recent studies confirmed that the hypoglycemic drug metformin (Met) exerted various antitumor effects, protected neural cells, and improved immunity, while arsenic trioxide (ATO) is an effective chemotherapeutic agent for the clinical treatment of leukemia and various solid tumors. However, the possible combined antitumor effects of Met and ATO and their cellular molecular mechanisms are unclear. We investigated the role of Parkin-mediated mitochondrial mitophagy in the anti-tumor mechanism of Met and ATO by studying the effects of Met and/or ATO on the proliferation and apoptosis of cervical cancer HeLa cells. Both Met and ATO effectively inhibited the proliferative activity of HeLa cells and induced apoptosis by activating Bax and inhibiting Bcl-2. Met and ATO treatment alone or in combination stimulated mitophagosome accumulation in HeLa cells, increased the conversion of microtubule-associated protein light chain 3 (LC3)-I to LC3-II, and decreased levels of the mitophagic lysosomal substrate protein P62. The mitochondrial membrane potential of HeLa cells also decreased, accompanied by activation of the mitochondrial translocase TOM system and the Pink1/Parkin signaling pathway. These results suggested that Met and/or ATO could induce mitophagy in HeLa cells via the Pink1/Parkin signaling pathway, leading to mitophagic apoptosis and inhibition of tumor cell proliferation. The combination of Met and ATO thus has enhanced antitumor effects, suggesting that this combination has potential clinical applications for the treatment of cervical cancer and other tumors.

Diagnosis and management of an endometrial cancer patient with Cowden syndrome

Somatic PTEN alterations are common in endometrial carcinoma (EC), but in rare cases PTEN mutations are associated with inherited syndromes. Here, we present a case of Cowden syndrome-associated EC. We discuss clinical, pathologic and molecular features of her tumor and PTEN-mutated EC, inherited syndromes predisposing to EC and PTEN-targeted therapies.

Transcriptomic Analysis of Gene Networks Regulated by U11 Small Nuclear RNA in Bladder Cancer

Small nuclear RNA is a class of non-coding RNA that widely exist in the nucleus of eukaryotes. Accumulated evidences have shown that small nuclear RNAs are associated with the regulation of gene expression in various tumor types. To explore the gene expression changes and its potential effects mediated by U11 snRNA in bladder cancer cells, U11 snRNA knockout and overexpressed cell lines were constructed and further used to analyze the gene expression changes by RNA sequencing. The differentially expressed genes were found to be mainly enriched in tumor-related pathways both in the U11 knockout and overexpression cell lines, such as NF-kappa B signaling pathway, bladder cancer and PI3K-Akt signaling pathway. Furthermore, alternative splicing events were proposed to participate in the potential regulatory mechanism induced by the U11 knockout or overexpression. In conclusion, U11 may be involved in the regulation of gene expression in bladder cancer cells, which may provide a potentially new biomarker for clinical diagnosis and treatment of bladder cancer.

Enhanced Efficacy of Aurora Kinase Inhibitors in G2/M Checkpoint Deficient TP53 Mutant Uterine Carcinomas Is Linked to the Summation of LKB1-AKT-p53 Interactions

Simple Summary

Cancers arising from the lining of the uterus, endometrial cancers, are the most common gynecologic malignancy in the United States. Once endometrial cancer escapes the uterus and grows in distant locations, there are limited therapeutic options. The most aggressive and lethal endometrial cancers carry alterations in the protein p53, which is a critical guardian of many cellular functions. The role of these p53 alterations in endometrial cancer is not well understood. The goal of this work was to use p53 altered models of endometrial cancer to understand which, if any, therapeutically targetable vulnerabilities these p53 alterations may confer in endometrial cancer. Here we show that many of these p53 altered cells have problems with cell division which can be targeted with novel single and combination therapies. These discoveries may lead to relevant new therapies for difficult to treat advanced stage endometrial cancers.

Abstract

Uterine carcinoma (UC) is the most common gynecologic malignancy in the United States. TP53 mutant UCs cause a disproportionate number of deaths due to limited therapies for these tumors and the lack of mechanistic understanding of their fundamental vulnerabilities. Here we sought to understand the functional and therapeutic relevance of TP53 mutations in UC. We functionally profiled targetable TP53 dependent DNA damage repair and cell cycle control pathways in a panel of TP53 mutant UC cell lines and patient-derived organoids. There were no consistent defects in DNA damage repair pathways. Rather, most models demonstrated dependence on defective G2/M cell cycle checkpoints and subsequent upregulation of Aurora kinase-LKB1-p53-AKT signaling in the setting of baseline mitotic defects. This combination makes them sensitive to Aurora kinase inhibition. Resistant lines demonstrated an intact G2/M checkpoint, and combining Aurora kinase and WEE1 inhibitors, which then push these cells through mitosis with Aurora kinase inhibitor-induced spindle defects, led to apoptosis in these cases. Overall, this work presents Aurora kinase inhibitors alone or in combination with WEE1 inhibitors as relevant mechanism driven therapies for TP53 mutant UCs. Context specific functional assessment of the G2/M checkpoint may serve as a biomarker in identifying Aurora kinase inhibitor sensitive tumors.

OSU-03012 Disrupts Akt Signaling and Prevents Endometrial Carcinoma Progression in vitro and in vivo

Purpose

OSU-03012 is a celecoxib derivative lacking cyclooxygenase-2 inhibitory activity and a potent PDK1 inhibitor which has been shown to inhibit tumor growth in various ways. However, the role of OSU-03012 in endometrial carcinoma (EC) in which the PI3K/Akt signaling pathway highly activated has not been studied. Here, we determined the potency of OSU-03012 in suppressing EC progression in vitro and in vivo, and studied the underlined mechanisms.

Methods

The human EC Ishikawa and HEC-1A cells were used as the in vitro models. CCK8 assay and flow cytometry were conducted to evaluate cell proliferation, cell cycle progression, and apoptosis. The metastatic ability was evaluated using the transwell migration assay. The Ishikawa xenograft tumor model was used to study the inhibitory effects of OSU-03012 on EC growth in vivo. Western blot analysis was performed to evaluate expressions of the cell cycle and apoptosis associated proteins.

Results

OSU-03012 could inhibit the progression of EC both in vitro and in vivo by disrupting Akt signaling. It reduced the metastatic ability of EC, led to G2/M cell cycle arrest and induced apoptosis via the mitochondrial apoptosis pathway.

Conclusion

Our data indicated that OSU-03012 could inhibit the progression of EC in vitro and in vivo. It can potentially be used as the targeted drug for the treatment of EC by inhibiting Akt signaling.

ESGO/ESTRO/ESP Guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

NLRC5 promotes cell migration and invasion by activating the PI3K/AKT signaling pathway in endometrial cancer

Objective

NOD-like receptor family caspase recruitment domain family domain-containing 5 (NLRC5) is involved in the development of cancer. Our objective was to explore the role of NLRC5 in the progression of endometrial cancer (EC).

Methods

The roles of NLRC5 in migration and invasion of AN3CA EC cells were examined by cell wound-healing assay, Transwell migration, and invasion analysis. Overexpression of NLRC5 was achieved with NLRC5 plasmid, and knockdown of NLRC5 was achieved using small interfering (si)RNA-NLRC5 in AN3CA cells. The expression of NLRC5 was detected by immunohistochemical, western blot, and quantitative real-time PCR. LY294002 was used to inhibit the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway.

Results

NLRC5 was downregulated in EC tissue compared with normal endometrium. Overexpression of NLRC5 led to upregulation of cell migration and invasion in AN3CA cells and expression of matrix metallopeptidase (MMP)-9. Inhibition of NLRC5 restricted migration and invasion of AN3CA cells and expression of MMP9. Overexpression of NLRC5 promoted the activation of PI3K/AKT signaling pathway. Inhibiting PI3K/AKT signaling pathway by using LY294002 blocked the positive role of NLRC5 in migration and invasion of AN3CA cells and expression of MMP9.

Conclusions

These results demonstrate that NLRC5 promotes EC progression by activating the PI3K/AKT signaling pathway.

Pharmacologic inhibition of Akt in combination with chemotherapeutic agents effectively induces apoptosis in ovarian and endometrial cancer cell lines

The PI3K/Akt signaling pathway, the most frequently altered signaling system in human cancer, is a crucial inducer of dysregulated proliferation and neoplastic processes; however, few therapeutic strategies using PI3K/Akt inhibitors singly have been shown to be effective. The purpose of this paper was to underline the potential benefit of pharmacological modulation of the PI3K/Akt pathway when combined with specific chemotherapeutic regimens. We have studied the ability of NVP‐BEZ235 (PI3K/mTOR inhibitor) and AZD5363 (Akt inhibitor) in the sensitization of cancer cells to cisplatin and doxorubicin. Our results show that NVP‐BEZ235 sensitizes cells preferentially to cisplatin while AZD5363 sensitizes cells to doxorubicin. At equal concentrations (5 μm), both inhibitors reduce ribosomal protein S6 phosphorylation, but AZD5363 is more effective in reducing GSK3β phosphorylation as well as S6 phosphorylation. Additionally, AZD5363 is capable of inducing FOXO1 and p53 nuclear localization and reduces BAD phosphorylation, which is generally increased by cisplatin and doxorubicin. Finally, the combination of AZD5363 and doxorubicin induces apoptosis in cells and robustly reduces cell ability to clonally replicate, which underlines a potential cooperative effect of the studied compounds.

Inhibition of PFKFB3 induces cell death and synergistically enhances chemosensitivity in endometrial cancer

The advanced or recurrent endometrial cancer (EC) has a poor prognosis because of chemoresistance. 6-Phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a glycolytic enzyme, is overexpressed in a variety of human cancers and plays important roles in promoting tumor cell growth. Here, we showed that high expression of PFKFB3 in EC cell lines is associated with chemoresistance. Pharmacological inhibition of PFKFB3 with PFK158 and or genetic downregulation of PFKFB3 dramatically suppressed cell proliferation and enhanced the sensitivity of EC cells to carboplatin (CBPt) and cisplatin (Cis). Moreover, PFKFB3 inhibition resulted in reduced glucose uptake, ATP production, and lactate release. Notably, we found that PFK158 with CBPt or Cis exerted strong synergistic antitumor activity in chemoresistant EC cell lines, HEC-1B and ARK-2 cells. We also found that the combination of PFK158 and CBPt/Cis induced apoptosis- and autophagy-mediated cell death through inhibition of the Akt/mTOR signaling pathway. Mechanistically, we found that PFK158 downregulated the CBPt/Cis-induced upregulation of RAD51 expression and enhanced CBPt/Cis-induced DNA damage as demonstrated by an increase in γ-H2AX levels in HEC-1B and ARK-2 cells, potentially revealing a means to enhance PFK158-induced chemosensitivity. More importantly, PFK158 treatment, either as monotherapy or in combination with CBPt, led to a marked reduction in tumor growth in two chemoresistant EC mouse xenograft models. These data suggest that PFKFB3 inhibition alone or in combination with standard chemotherapy may be used as a novel therapeutic strategy for improved therapeutic efficacy and outcomes of advanced and recurrent EC patients.

The Potential Role of N6-Methyladenosine (m6A) Demethylase Fat Mass and Obesity-Associated Gene (FTO) in Human Cancers

N6-methyladenosine (m6A) demethylase fat mass and obesity-associated gene(FTO), previously recognized to be related with obesity and diabetes, was gradually discovered to be dysregulated in multiple cancers and plays an oncogenic or tumor-suppressive role. However, the specific expression and pro- or anti-cancer role of FTO in various cancers remained controversial. In this review, through summarizing the available literature, we found that FTO single nucleotide polymorphisms (SNPs) were closely related with cancer risk. Additionally, the dysregulation of FTO was implicated in multiple biological processes, such as cancer cell apoptosis, proliferation, migration, invasion, metastasis, cell-cycle, differentiation, stem cell self-renewal and so on. These modulations mostly relied on the communications between FTO and specific signaling pathways, including PI3K/AKT, MAPK and mTOR signaling pathways. Furthermore, FTO had great potential for clinical application by serving as a prognostic biomarker.

Kinome Profiling of Primary Endometrial Tumors Using Multiplexed Inhibitor Beads and Mass Spectrometry Identifies SRPK1 as Candidate Therapeutic Target

Endometrial carcinoma (EC) is the most common gynecologic malignancy in the United States, with limited effective targeted therapies. Endometrial tumors exhibit frequent alterations in protein kinases, yet only a small fraction of the kinome has been therapeutically explored. To identify kinase therapeutic avenues for EC, we profiled the kinome of endometrial tumors and normal endometrial tissues using Multiplexed Inhibitor Beads and Mass Spectrometry (MIB-MS). Our proteomics analysis identified a network of kinases overexpressed in tumors, including Serine/Arginine-Rich Splicing Factor Kinase 1 (SRPK1). Immunohistochemical (IHC) analysis of endometrial tumors confirmed MIB-MS findings and showed SRPK1 protein levels were highly expressed in endometrioid and uterine serous cancer (USC) histological subtypes. Moreover, querying large-scale genomics studies of EC tumors revealed high expression of SRPK1 correlated with poor survival. Loss-of-function studies targeting SRPK1 in an established USC cell line demonstrated SRPK1 was integral for RNA splicing, as well as cell cycle progression and survival under nutrient deficient conditions. Profiling of USC cells identified a compensatory response to SRPK1 inhibition that involved EGFR and the up-regulation of IGF1R and downstream AKT signaling. Co-targeting SRPK1 and EGFR or IGF1R synergistically enhanced growth inhibition in serous and endometrioid cell lines, representing a promising combination therapy for EC.

Endometrial cancer-is our knowledge changing?

In developed countries, endometrial cancer (EC) is the most frequent gynecologic malignancy in postmenopausal women. At the same time, EC has become one of the most common cancers in numerous developing countries, probably influenced by global epidemic of obesity. The majority of patients have low-grade endometrioid cancer with a high 5-year survival rate, but with high-risk EC, the survival rates are still rather low. However, despite intensive research in last decades, our knowledge of the mechanisms, risk factors, diagnosis and treatment have not significantly improved. The standard treatment of all types of EC is still a traditional combination of surgery, irradiation and/or chemotherapy, despite the fact that each of these options is not without having some negative side effects. Despite the fact that on the molecular level, EC is relatively well-studied, but the efforts to transform these findings into either diagnosis or therapies of EC remain elusive. In addition, some research into risk factors involved in the development or progression of EC seems to be more a fishing expedition than a well thought-out approach. The purpose of this review is to summarize the most recent developments in the search for biomarkers and prognostic markers and to discuss the progress in EC treatment.

Key factors mediated by PI3K signaling pathway and related genes in endometrial carcinoma

By analyzing the gene expression of endometrial carcinoma (EC) patients, the key factors in PI3K signaling pathway and its related genes mediating EC were explored. The EC samples and normal endometrial samples were downloaded from TCGA database and GTEx database. The R language "limma" package was used for differential analysis, and the expression level of genes in each tissue was analyzed by "gganatogram" package. Functional enrichment analysis of differential genes was carried out by KOBAS, an online bioinformatics website. The correlation between key genes and differential genes was evaluated using TCGA data and GTEx combined gene expression data. The corresponding clinical data were downloaded from TCGA database and GTEx database, and the R language "survival" package was used to assess the potential of candidate differential genes as a key factor of EC. Based on the combined differential analysis of TCGA and GTEx databases, 299 genes with significant differential in expression were finally got. Functional enrichment analysis revealed that genes were predominantly enriched in the entry of "Pathways in cancer", including RAC2 and PIK3R3 genes which were related with the abnormal PI3K pathway in cancer. PIK3R3, a key gene in the PI3K signaling pathway, was highly-expressed in EC. SPDEF, GCNT2, KIAA1324, C9orf152, MARVELD3, and APEX2 genes were found to be positively correlated with PIK3R3 in EC, all of which were highly expressed in EC. KM survival analysis showed that SPDEF, GCNT2, KIAA1324 and C9orf152 were significantly correlated with patients' survival. ROC analysis showed that SPDEF, GCNT2, KIAA1324 and C9orf152 gene could be used as potential markers for prognosis and survival of EC patients. It was found that PIK3R3, a key gene in the PI3K signaling pathway, was highly expressed in EC. The SPDEF, GCNT2, KIAA1324 and C9orf152 genes were also highly expressed in EC, and were positively correlated with PIK3R3 in EC. Moreover, they are significantly correlated with the patients' survival, suggesting that they may be potential markers for the prognosis of patients with EC.

Histomolecular features of high-grade endometrial cancers

High-grade endometrial cancers (ECs) are an aggressive subset of ECs accounting for 70-80% of EC-related deaths. Currently, staging surgery, together with chemotherapy or radiotherapy, is the primary treatment strategy for these cancers. The widespread use of next-generation sequencing has led to a refined understanding of EC's genomics with important information for diagnosis and therapy for individual patients (precision medicine). However, advances in the genomics assessment of high-grade tumors have been slower due to their lower incidence than low-grade EC. This article will briefly introduce the current state of knowledge of the genomics of G3 endometrioid EC, serous uterine cancer, clear cell uterine carcinoma and uterine carcinosarcoma and discuss its implications for diagnosis and targeted therapy.

Therapeutic effect of metformin in the treatment of endometrial cancer

The present review aims at reviewing the role of metformin in the treatment of endometrial cancer (EC). According to the literature, excessive estrogen levels and insulin resistance are established risk factors of EC. As a traditional insulin sensitizer and newly discovered anticancer agent, metformin directly and indirectly inhibits the development of EC. The direct mechanisms of metformin include inhibition of the LKB1-AMP-activated protein kinase-mTOR, PI3K-Akt and insulin-like growth factor 1-related signaling pathways, which reduces the proliferation and promotes the apoptosis of EC cells. In the indirect mechanism, metformin increases the insulin sensitivity of body tissues and decreases circulating insulin levels. Decreased levels of insulin increase the blood levels of sex hormone binding globulin, which leads to reductions in circulating estrogen and androgens. The aforementioned findings suggest that metformin serves an important role in the treatment of EC. Increased understanding of the mechanism of metformin in EC may provide novel insights into the treatment of this malignancy.

Targeted therapies in gynecological cancers: a comprehensive review of clinical evidence

Advanced and recurrent gynecological cancers are associated with poor prognosis and lack of effective treatment. The developments of the molecular mechanisms on cancer progression provide insight into novel targeted therapies, which are emerging as groundbreaking and promising cancer treatment strategies. In gynecologic malignancies, potential therapeutic targeted agents include antiangiogenic agents, poly (ADP-ribose) polymerase (PARP) inhibitors, tumor-intrinsic signaling pathway inhibitors, selective estrogen receptor downregulators, and immune checkpoint inhibitors. In this article, we provide a comprehensive review of the clinical evidence of targeted agents in gynecological cancers and discuss the future implication.

Preclinical Efficacy and Involvement of AKT, mTOR, and ERK Kinases in the Mechanism of Sulforaphane against Endometrial Cancer

Sulforaphane exerts anti-cancer activity against multiple cancer types. Our objective was to evaluate utility of sulforaphane for endometrial cancer therapy. Sulforaphane reduced viability of endometrial cancer cell lines in association with the G2/M cell cycle arrest and cell division cycle protein 2 (Cdc2) phosphorylation, and intrinsic apoptosis. Inhibition of anchorage-independent growth, invasion, and migration of the cell lines was associated with sulforaphane-induced alterations in epithelial-to-mesenchymal transition (EMT) markers of increased E-cadherin and decreased N-cadherin and vimentin expression. Proteomic analysis identified alterations in AKT, mTOR, and ERK kinases in the networks of sulforaphane effects in the Ishikawa endometrial cancer cell line. Western blots confirmed sulforaphane inhibition of AKT, mTOR, and induction of ERK with alterations in downstream signaling. AKT and mTOR inhibitors reduced endometrial cancer cell line viability and prevented further reduction by sulforaphane. Accumulation of nuclear phosphorylated ERK was associated with reduced sensitivity to the ERK inhibitor and its interference with sulforaphane activity. Sulforaphane induced apoptosis-associated growth inhibition of Ishikawa xenograft tumors to a greater extent than paclitaxel, with no evidence of toxicity. These results verify sulforaphane's potential as a non-toxic treatment candidate for endometrial cancer and identify AKT, mTOR, and ERK kinases in the mechanism of action with interference in the mechanism by nuclear phosphorylated ERK.

VEGFR2 Blockade Improves Renal Damage in an Experimental Model of Type 2 Diabetic Nephropathy

The absence of optimal treatments for Diabetic Nephropathy (DN) highlights the importance of the search for novel therapeutic targets. The vascular endothelial growth factor receptor 2 (VEGFR2) pathway is activated in experimental and human DN, but the effects of its blockade in experimental models of DN is still controversial. Here, we test the effects of a therapeutic anti-VEGFR2 treatment, using a VEGFR2 kinase inhibitor, on the progression of renal damage in the BTBR ob/ob (leptin deficiency mutation) mice. This experimental diabetic model develops histological characteristics mimicking the key features of advanced human DN. A VEGFR2 pathway-activation blockade using the VEGFR2 kinase inhibitor SU5416, starting after kidney disease development, improves renal function, glomerular damage (mesangial matrix expansion and basement membrane thickening), tubulointerstitial inflammation and tubular atrophy, compared to untreated diabetic mice. The downstream mechanisms involved in these beneficial effects of VEGFR2 blockade include gene expression restoration of podocyte markers and downregulation of renal injury biomarkers and pro-inflammatory mediators. Several ligands can activate VEGFR2, including the canonical ligands VEGFs and GREMLIN. Activation of a GREMLIN/VEGFR2 pathway, but not other ligands, is correlated with renal damage progression in BTBR ob/ob diabetic mice. RNA sequencing analysis of GREMLIN-regulated genes confirm the modulation of proinflammatory genes and related-molecular pathways. Overall, these data show that a GREMLIN/VEGFR2 pathway activation is involved in diabetic kidney disease and could potentially be a novel therapeutic target in this clinical condition.

PI3K/AKT/mTOR inhibitors for advanced or recurrent endometrial cancer

BACKGROUND

Endometrial cancer is one of the most common gynaecological cancers in developed countries. Treatment of advanced endometrial cancer usually involves radiotherapy, chemotherapy, endocrine therapy or a combination of these. However, survival outcomes are poor in advanced or metastatic disease. Better systemic treatment options are needed to improve survival and safety outcomes for these women. The PI3K/AKT/mTOR pathway is a frequently altered signalling pathway in endometrial cancer. Single-arm studies have reported some encouraging results of the PI3K/AKT/mTOR inhibition in advanced or recurrent endometrial cancer.

OBJECTIVES

To assess the efficacy and safety of PI3K/AKT/mTOR inhibitor-containing regimens in women with locally-advanced, metastatic or recurrent endometrial cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE and Embase to 16 January 2019; and the World Health Organization's International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov in July 2018. We also reviewed reference lists from included studies and endometrial cancer guidelines.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing a regimen with a PI3K/AKT/mTOR inhibitor (either alone or in combination with other treatments, such as chemotherapy or hormonal therapy) versus a comparator regimen without a PI3K/AKT/mTOR inhibitor. There were no restrictions on which comparator(s) were included.

DATA COLLECTION AND ANALYSIS

We extracted data independently, and assessed risks of bias and the certainty of the evidence. The primary outcome measures were progression-free survival and toxicity (grade 3/4 where available). We derived hazard ratios (HRs) for time-to-event outcomes and risk ratios (RRs) for dichotomous outcomes. Secondary outcomes included overall survival, objective tumour response rate, quality of life and treatment-related death. We used GRADEproGDT to assess the certainty of the evidence for the most important outcomes (by first-line and second/third-line therapy for progression-free survival and overall survival).

MAIN RESULTS

We included two RCTs involving 361 women. One study assessed the effects of the mTOR inhibitor temsirolimus, in combination with carboplatin/paclitaxel versus carboplatin/paclitaxel and bevacizumab in treatment-naïve women with advanced or recurrent endometrial cancer. The second study compared the mTOR inhibitor ridaforolimus alone versus progestin or investigator choice of chemotherapy in women who had received prior treatment for metastatic or recurrent endometrial cancer. We identified five ongoing studies on the effects of PI3K and AKT inhibitors, metformin and dual mTOR inhibitors.For first-line therapy, an mTOR inhibitor-containing regimen may worsen progression-free survival (HR 1.43, 95% CI 1.06 to 1.93; 1 study, 231 participants; low-certainty evidence), while for second/third-line therapy, an mTOR inhibitor probably improves progression-free survival compared to chemotherapy or endocrine therapy (HR 0.53, 95% CI 0.31 to 0.91; 1 study, 95 participants; moderate-certainty evidence). Data on toxicity were available from both studies: administering an mTOR inhibitor regimen may increase the risk of grade 3/4 mucositis (RR 10.42, 95% CI 1.34 to 80.74; 2 studies, 357 participants; low-certainty evidence), but may result in little to no difference in risk of anaemia or interstitial pneumonitis (low-certainty evidence for both toxicities). Overall, event rates were low. For first-line therapy, an mTOR inhibitor-containing regimen may result in little to no difference in overall survival compared to chemotherapy (HR 1.32, 95% CI 0.98 to 1.781 study, 231 participants; low-certainty evidence). The finding was similar for second/third-line therapy (HR 1.06, 95% CI 0.70 to 1.61; 1 study, 130 participants; low-certainty evidence). Administering mTOR inhibitor-containing regimens may result in little to no difference in tumour response compared to chemotherapy or hormonal therapy in first-line or second/third-line therapy (first line: RR 0.93, 95% CI 0.75 to 1.17; 1 study, 231 participants; second/third line: RR 0.22, 95% CI 0.01 to 4.40; 1 study, 61 participants; low-certainty evidence).Neither study collected or reported quality-of-life data.

AUTHORS' CONCLUSIONS

Two RCTs have been reported to date, with low certainty of evidence. In a recurrent disease setting, mTOR inhibitors may result in improved progression-free survival, but we found no clear benefit in overall survival or tumour response rate. We await the publication of at least five ongoing studies investigating the role of PI3K/AKT/mTOR inhibitors in advanced or recurrent endometrial cancer before any conclusions can be drawn on their use.