Receptor tyrosine kinases in PI3K signaling: The therapeutic targets in cancer

c-KIT inhibitors reduce pathology and improve behavior in the Tg(SwDI) model of Alzheimer's disease

Treatments for Alzheimer's disease have primarily focused on removing brain amyloid plaques to improve cognitive outcomes in patients. We developed small compounds, known as BK40143 and BK40197, and we hypothesize that these drugs alleviate microglial-mediated neuroinflammation and induce autophagic clearance of neurotoxic proteins to improve behavior in models of neurodegeneration. Specificity binding assays of BK40143 and BK40197 showed primary binding to c-KIT/Platelet Derived Growth Factor Receptors (PDGFR)α/β, whereas BK40197 also differentially binds to FYVE finger-containing phosphoinositide kinase (PIKFYVE). Both compounds penetrate the CNS, and treatment with these drugs inhibited the maturation of peripheral mast cells in transgenic mice, correlating with cognitive improvements on measures of memory and anxiety. In the brain, microglial activation was profoundly attenuated and amyloid-beta and tau were reduced via autophagy. Multi-kinase inhibition, including c-KIT, exerts multifunctional effects to reduce neurodegenerative pathology via autophagy and microglial activity and may represent a potential therapeutic option for neurodegeneration.

Overcoming Resistance in Cancer Therapy: Computational Exploration of PIK3CA Mutations, Unveiling Novel Non-Toxic Inhibitors, and Molecular Insights Into Targeting PI3Kα

Phosphoinositide-3-kinases (PI3 K) are pivotal regulators of cell signaling implicated in various cancers. Particularly, mutations in the PIK3CA gene encoding the p110α catalytic subunit drive oncogenic signaling, making it an attractive therapeutic target. Our study conducted in silico exploration of 31 PIK3CA mutations across breast, endometrial, colon, and ovarian cancers, assessing their impacts on response to PI3Kα inhibitors and identifying potential non-toxic inhibitors and also elucidating their effects on protein stability and flexibility. Specifically, we observed significant alterations in the stability and flexibility of the PI3 K protein induced by these mutations. Through molecular docking analysis, we evaluated the binding interactions between the selected inhibitors and the PI3 K protein. The filtration of ligands involved calculating chemical descriptors, incorporating Veber and Lipinski rules, as well as IC50 values and toxicity predictions. This process reduced the initial dataset of 1394 ligands to 12 potential non-toxic inhibitors, and four reference inhibitors with significant biological activity in clinical trials were then chosen based on their physico-chemical properties. This analysis revealed Lig5's exceptional performance, exhibiting superior affinity and specificity compared to established reference inhibitors such as pictilisib. Lig5 formed robust binding interactions with the PI3 K protein, suggesting its potential as a highly effective therapeutic agent against PI3 K-driven cancers. Furthermore, molecular dynamics simulations provided valuable insights into Lig5's stability and its interactions with PI3 K over 100 ns. These simulations supported Lig5's potential as a versatile inhibitor capable of effectively targeting various mutational profiles of PI3 K, thereby mitigating issues related to resistance and toxicity commonly associated with current inhibitors.

The Multifaceted Effects of Non-Steroidal and Non-Opioid Anti-Inflammatory and Analgesic Drugs on Platelets: Current Knowledge, Limitations, and Future Perspectives

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely utilized pharmaceuticals worldwide. Besides their recognized anti-inflammatory effects, these drugs exhibit various other pleiotropic effects in several cells, including platelets. Within this article, the multifaceted properties of NSAIDs on platelet functions, activation and viability, as well as their interaction(s) with established antiplatelet medications, by hindering several platelet agonists' pathways and receptors, are thoroughly reviewed. The efficacy and safety of NSAIDs as adjunctive therapies for conditions involving inflammation and platelet activation are also discussed. Emphasis is given to the antiplatelet potential of commonly administered NSAIDs medications, such as ibuprofen, diclofenac, naproxen and ketoprofen, alongside non-opioid analgesic and antipyretic medications like paracetamol. This article delves into their mechanisms of action against different pathways of platelet activation, aggregation and overall platelet functions, highlighting additional health-promoting properties of these anti-inflammatory and analgesic agents, without neglecting the induced by these drugs' side-effects on platelets' functionality and thrombocytopenia. Environmental issues emerging from the ever-increased subscription of these drugs are also discussed, along with the need for novel water treatment methodologies for their appropriate elimination from water and wastewater samples. Despite being efficiently eliminated during wastewater treatment processes on occasion, NSAIDs remain prevalent and are found at significant concentrations in water bodies that receive effluents from wastewater treatment plants (WWTPs), since there is no one-size-fits-all solution for removing all contaminants from wastewater, depending on the specific characteristics of the wastewater. Several novel methods have been studied, with adsorption being proposed as a cost-effective and environmentally friendly method for wastewater purification from such drugs. This article also presents limitations and future prospects regarding the observed antiplatelet effects of NSAIDs, as well as the potential of novel derivatives of these compounds, with benefits in other important platelet functions.

Abdominal inflammatory myofibroblastic tumour: Clinicopathological and molecular analysis of 20 cases, highlighting potential therapeutic targets

AIMS

Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm of intermediate malignant potential, occurring at any age and at multiple sites. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive subtype of IMT, typically involving the abdomen. Most IMTs harbour kinase gene fusions, especially involving ALK and ROS1, but 20-30% of IMTs show no detectable translocations. The aim of this study is to further delineate clinicopathological and molecular characteristics of abdominal IMT and discover potential new therapeutic targets.

METHODS AND RESULTS

In 20 IMTs, including four EIMS, RNA fusion analysis was performed, followed by multiplex DNA analysis if no ALK or ROS1 fusion was detected. Fourteen IMTs (70.0%) had an ALK translocation and the fusion partner was identified in 11, including a RRBP1::ALK fusion, not previously described in classical (non-EIMS) IMT. RANBP2::ALK fusion was demonstrated in all EIMS. One IMT had a ROS1 fusion. In all ALK/ROS1 translocation-negative IMTs mutations or fusions - as yet unreported in primary IMT - were found in genes related to the receptor tyrosine kinase (RTK)/PI3K/AKT pathway. Three of four patients with EIMS died of disease [mean survival 8 months (4-15 months)], whereas only one of 14 classical IMT patients succumbed to disease [mean follow-up time 52 months (2-204 months); P < 0.01].

CONCLUSION

This study shows the wide clinical spectrum of abdominal IMTs and affirms the poor prognosis of EIMS, raising discussion about its status as IMT subtype. Furthermore, the newly detected alterations of the RTK/PI3K/AKT pathway expand the molecular landscape of IMTs and provide potential therapeutic targets.

Regulation of ferroptosis by PI3K/Akt signaling pathway: a promising therapeutic axis in cancer

The global challenge posed by cancer, marked by rising incidence and mortality rates, underscores the urgency for innovative therapeutic approaches. The PI3K/Akt signaling pathway, frequently amplified in various cancers, is central in regulating essential cellular processes. Its dysregulation, often stemming from genetic mutations, significantly contributes to cancer initiation, progression, and resistance to therapy. Concurrently, ferroptosis, a recently discovered form of regulated cell death characterized by iron-dependent processes and lipid reactive oxygen species buildup, holds implications for diseases, including cancer. Exploring the interplay between the dysregulated PI3K/Akt pathway and ferroptosis unveils potential insights into the molecular mechanisms driving or inhibiting ferroptotic processes in cancer cells. Evidence suggests that inhibiting the PI3K/Akt pathway may sensitize cancer cells to ferroptosis induction, offering a promising strategy to overcome drug resistance. This review aims to provide a comprehensive exploration of this interplay, shedding light on the potential for disrupting the PI3K/Akt pathway to enhance ferroptosis as an alternative route for inducing cell death and improving cancer treatment outcomes.

Acalabrutinib as a novel hope for the treatment of breast and lung cancer: an in-silico proof of concept

Drug repurposing is proved to be a groundbreaking concept in the field of cancer research, accelerating the pace of de novo drug discovery by investigating the anti-cancer activity of the already approved drugs. On the other hand, it got highly benefitted from the advancement in the in-silico tools and techniques, which are used to build up the initial "proof of concept" based on the drug-target interaction. Acalabrutinib (ACL) is a well-known drug for the treatment of hematological malignancies. But, the therapeutic ability of ACL against solid tumors is still unexplored. Thereby, the activity of ACL on breast cancer and lung cancer was evaluated utilizing different computational methods. A series of proteins such as VEGFR1, ALK, BCL2, CXCR-4, mTOR, AKT, PI3K, HER-2, and Estrogen receptors were selected based on their involvement in the progression of the breast as well as lung cancer. A multi-level computational study starting from protein-ligand docking to molecular dynamic (MD) simulations were performed to detect the binding potential of ACL towards the selected proteins. Results of the study led to the identification of ACL as a ligand that showed a high docking score and binding energy with HER-2, mTOR, and VEGFR-1 successively. Whereas, the MD simulations study has also shown good docked complex stability of ACL with HER2 and VEGFR1. Our findings suggest that interaction with those receptors can lead to preventive action on both breast and lung cancer, thus it can be concluded that ACL could be a potential molecule for the same purpose.Communicated by Ramaswamy H. Sarma.

Heart Failure Post-Myocardial Infarction Promotes Mammary Tumor Growth Through the NGF-TRKA Pathway

Background

Epidemiological investigations suggest that patients with heart failure have a higher incidence of cancer; however, the causal role of cardiac disease on cancer progression remains unclear.

Objectives

This study aimed to investigate the impact and underlying mechanisms of myocardial infarction (MI)-induced heart failure on tumor cell growth.

Methods

We generated a syngeneic mouse model by implanting mammary tumor-derived 4T1 cells into BALB/c mice with MI resulting from ligation of the left anterior descending artery.

Results

Mice with MI exhibited increased tumor volume, tumor weight, and Ki67-positive proliferative cells in the tumor tissue compared with the sham-operated mice. Furthermore, RNA sequencing analysis in the tumor tissue revealed significant enrichment of pathways related to tumor progression, particularly the PI3K-AKT pathway in the MI mice. Upregulation of tropomyosin receptor kinase A (TRKA) phosphorylation, an upstream regulator of PI3K-AKT signaling, was observed in the tumor tissue of the MI mice. We also observed elevated levels of circulating nerve growth factor (NGF), a ligand of TRKA, and increased NGF expressions in the myocardium after MI. In in vitro experiments, NGF stimulation led to increased cell proliferation, as well as phosphorylation of TRKA and AKT. Notably, inhibition of TRKA by small interfering RNA or the chemical inhibitor GW441756 effectively blocked these effects. Administration of GW441756 resulted in the suppression of tumor volume and cell proliferation in the MI mice.

Conclusions

Our study demonstrates that MI promotes mammary tumor growth through the NGF-TRKA pathway. Consequently, inhibiting TRKA could represent a therapeutic strategy for breast cancer patients concurrently experiencing heart failure after MI.

Significance of flavonoids targeting PI3K/Akt/HIF-1α signaling pathway in therapy-resistant cancer cells - A potential contribution to the predictive, preventive, and personalized medicine

BACKGROUND

Cancer management faces multiple obstacles, including resistance to current therapeutic approaches. In the face of challenging microenvironments, cancer cells adapt metabolically to maintain their supply of energy and precursor molecules for biosynthesis and thus sustain rapid proliferation and tumor growth. Among the various metabolic adaptations observed in cancer cells, the altered glucose metabolism is the most widely studied. The aberrant glycolytic modification in cancer cells has been associated with rapid cell division, tumor growth, cancer progression, and drug resistance. The higher rates of glycolysis in cancer cells, as a hallmark of cancer progression, is modulated by the transcription factor hypoxia inducible factor 1 alpha (HIF-1α), a downstream target of the PI3K/Akt signaling, the most deregulated pathway in cancer.

AIM OF REVIEW

We provide a detailed overview of current, primarily experimental, evidence on the potential effectiveness of flavonoids to combat aberrant glycolysis-induced resistance of cancer cells to conventional and targeted therapies. The manuscript focuses primarily on flavonoids reducing cancer resistance via affecting PI3K/Akt, HIF-1α (as the transcription factor critical for glucose metabolism of cancer cells that is regulated by PI3K/Akt pathway), and key glycolytic mediators downstream of PI3K/Akt/HIF-1α signaling (glucose transporters and key glycolytic enzymes).

KEY SCIENTIFIC CONCEPTS OF REVIEW

The working hypothesis of the manuscript proposes HIF-1α - the transcription factor critical for glucose metabolism of cancer cells regulated by PI3K/Akt pathway as an attractive target for application of flavonoids to mitigate cancer resistance. Phytochemicals represent a source of promising substances for cancer management applicable to primary, secondary, and tertiary care. However, accurate patient stratification and individualized patient profiling represent crucial steps in the paradigm shift from reactive to predictive, preventive, and personalized medicine (PPPM / 3PM). The article is focused on targeting molecular patterns by natural substances and provides evidence-based recommendations for the 3PM relevant implementation.

Impact of human ovarian tissue manipulation on follicles: evidence of a potential first wave of follicle activation during fertility preservation procedures

PURPOSE

The aim of this study was to investigate the impact of processing human ovarian tissue on follicle activation dynamics.

METHODS

Fresh ovarian tissue was retrieved from 9 women undergoing laparoscopic surgery for benign conditions. Biopsies from each patient were divided into 3 fragments, the first of which was immediately fixed in the operating room (T0) and the second and third just after processing at 25 (T25) and (T90) 90 min. To evaluate follicle activation, markers of the PI3K and Hippo signaling pathways were immunolabeled at each time point, targeting phospho-Akt (p-Akt) by immunohistochemistry and yes-associated protein (YAP) cellular localization in the granulosa cell layer by immunofluorescence.

RESULTS

Four hundred forty primordial follicles were evaluated for p-Akt and 420 for YAP. Significantly stronger p-Akt expression was observed at T25 (23.01 ± 13.45%; p=0.04) and T90 (38.99 ± 25.21%; p<0.001) than at T0 (2.72 ± 3.35%). A significant nucleus-to-cytoplasm shift in YAP was detected at T25 (1.21 ± 0.25; p=0.015 compared to T0 (0.95 ± 0.09), while T90 (1.10 ± 0.16) values were similar to T25.

CONCLUSION

Our data prove that ovarian tissue manipulation significantly impacts follicle dynamics by stimulating the PI3K and Hippo signaling pathways involved in primordial follicle activation. Further experimental evidence must nevertheless be gathered to understand and gain control of follicle activation mechanisms in non-physiological conditions (like ovarian tissue manipulation), in order to optimize fertility preservation and restoration strategies.

Inhibition of PI3K Signaling Intensified the Antileukemic Effects of Pioglitazone: New Insight into the Application of PPARγ Stimulators in Acute Lymphoblastic Leukemia

Over the past two decades, molecular targeted therapy has revolutionized the landscape of cancer treatment due to lower side effects as well as higher anticancer effects. Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the nuclear hormone receptor which plays a crucial role in cell proliferation and death and the efficacy of PPARγ ligands either as monotherapy or in combination with traditional chemotherapy drugs has been proved by recent studies. In this study, we aimed to investigate the effects of pioglitazone, a well-known PPARγ stimulator, in ALL-derived NALM6 cells by using trypan blue assay, MTT assay, and flow cytometry analysis. Moreover, to investigate the molecular mechanism action of pioglitazone in these cells, we assessed the possible alterations in the expression of some target genes which regulate cell proliferation, apoptosis, and autophagy system. Our result demonstrated that pioglitazone induced a remarkable antileukemic effect on NALM6 cells through a PTEN-mediated manner. Based on the fact that PI3K hyperactivation is one of the main properties of ALL cells, the effects of PI3K inhibition using CAL-101 on pioglitazone-induced cytotoxicity were evaluated by combinatorial experiments. Moreover, the result of cell cycle assay and qRT-PCR demonstrated that pioglitazone-CAL-101 induced antileukemic effect mainly through induction of p21 and p27-mediated G1 arrest. Additionally, our result showed that inhibition of proteasome and autophagy system, two main cellular processes, increased the antileukemic effects of the agents. Taken together, we suggest a novel therapeutic application for PPARγ stimulators as a single agent or in combination with PI3K inhibitors that should be clinically evaluated in ALL patients.

Exploring the Functional Roles of Telomere Maintenance 2 in the Tumorigenesis of Glioblastoma Multiforme and Drug Responsiveness to Temozolomide

Glioblastoma multiforme (GBM) is a grade IV human glioma. It is the most malignant primary central nervous system tumor in adults, accounting for around 15% of intracranial neoplasms and 40-50% of all primary malignant brain tumors. However, the median survival time of GBM patients is still less than 15 months, even after treatment with surgical resection, concurrent chemoradiotherapy, and adjuvant chemotherapy with temozolomide (TMZ). Telomere maintenance 2 (TELO2) mRNA is highly expressed in high-grade glioma patients, and its expression correlates with shorter survival outcomes. Hence, it is urgent to address the functional role of TELO2 in the tumorigenesis and TMZ treatment of GBM. In this study, we knocked down TELO2 mRNA in GBM8401 cells, a grade IV GBM, compared with TELO2 mRNA overexpression in human embryonic glial SVG p12 cells and normal human astrocyte (NHA) cells. We first analyzed the effect of TELO2 on the Elsevier pathway and Hallmark gene sets in GBM8401, SVG p12, and NHA via an mRNA array analysis. Later, we further examined and analyzed the relationship between TELO2 and fibroblast growth factor receptor 3, cell cycle progression, epithelial-mesenchymal transient (EMT), reactive oxygen species (ROS), apoptosis, and telomerase activity. Our data showed that TELO2 is involved in several functions of GBM cells, including cell cycle progression, EMT, ROS, apoptosis, and telomerase activity. Finally, we examined the crosstalk between TELO2 and the responsiveness of TMZ or curcumin mediated through the TELO2-TTI1-TTI2 complex, the p53-dependent complex, the mitochondrial-related complex, and signaling pathways in GBM8401 cells. In summary, our work provides new insight that TELO2 might modulate target proteins mediated through the complex of phosphatidylinositol 3-kinase-related kinases in its involvement in cell cycle progression, EMT, and drug response in GBM patients.

Molecular markers related to patient outcome in patients with IDH-mutant astrocytomas grade 2 to 4: A systematic review

BACKGROUND

Grading and classification of IDH-mutant astrocytomas has shifted from solely histology towards histology combined with molecular diagnostics. In this systematic review, we give an overview of all currently known clinically relevant molecular markers within IDH-mutant astrocytomas grade 2 to 4.

METHODS

A literature search was performed in five electronic databases for English original papers on patient outcome with respect to a molecular marker as determined by DNA/RNA sequencing, micro-arrays, or DNA methylation profiling in IDH-mutant astrocytomas grade 2 to 4. Papers were included if molecular diagnostics were performed on tumour tissue of at least 15 IDH-mutant astrocytoma patients, and if the investigated molecular markers were not limited to the diagnostic markers MGMT, ATRX, TERT, and/or TP53.

RESULTS

The literature search identified 4508 unique articles, published between August 2012 and December 2021, of which ultimately 44 articles were included. Numerous molecular markers from these papers were significantly correlated to patient outcome. The associations between patient outcome and non-canonical IDH mutations, PI3K mutations, high expression of MSH2, high expression of RAD18, homozygous deletion of CDKN2A/B, amplification of PDGFRA, copy number neutral loss of chromosomal arm 17p, loss of chromosomal arm 19q, the G-CIMP-low DNA methylation cluster, high total CNV, and high tumour mutation burden were confirmed in multiple studies.

CONCLUSIONS

Multiple genetic and epigenetic markers are associated with survival in IDH-mutant astrocytoma patients. Commonly affected are the RB signalling pathway, the RTK-PI3K-mTOR signalling pathway, genomic stability markers, and (epigenetic) gene regulation.

The NF-κB Pharmacopeia: Novel Strategies to Subdue an Intractable Target

NF-κB transcription factors are major drivers of tumor initiation and progression. NF-κB signaling is constitutively activated by genetic alterations or environmental signals in many human cancers, where it contributes to almost all hallmarks of malignancy, including sustained proliferation, cell death resistance, tumor-promoting inflammation, metabolic reprogramming, tissue invasion, angiogenesis, and metastasis. As such, the NF-κB pathway is an attractive therapeutic target in a broad range of human cancers, as well as in numerous non-malignant diseases. Currently, however, there is no clinically useful NF-κB inhibitor to treat oncological patients, owing to the preclusive, on-target toxicities of systemic NF-κB blockade. In this review, we discuss the principal and most promising strategies being developed to circumvent the inherent limitations of conventional IκB kinase (IKK)/NF-κB-targeting drugs, focusing on new molecules that target upstream regulators or downstream effectors of oncogenic NF-κB signaling, as well as agents targeting individual NF-κB subunits.

Decrypting a path based approach for identifying the interplay between PI3K and GSK3 signaling cascade from the perspective of cancer

Cancer is one of those leading diseases worldwide, which takes millions of lives every year. Researchers are continuously looking for specific approaches to eradicate the deadly disease, ensuring minimal adverse effects along with more therapeutic significance. Targeting of different aberrantly regulated signaling pathways, involved in cancer, is surely one of the revolutionary chemotherapeutic approach. In this instance, GSK3 and PI3K signaling cascades are considered as important role player for both the oncogenic activation and inactivation which further leads to cancer proliferation and metastasis. In this review, we have discussed the potential role of GSK3 and PI3K signaling in cancer, and we further established the crosstalk between PI3K and GSK3 signaling, through showcasing their cross activation, cross inhibition and convergence pathways in association with cancer. We also exhibited the effect of GSK3 on the efficacy of PI3K inhibitors to overcome the drug resistance and preventing the cell proliferation, metastasis in a combinatorial way with GSK3 inhibitors for a better treatment strategy in clinical settings.

Evi1 involved in benzene-induced haematotoxicity via modulation of PI3K/mTOR pathway and negative regulation Serpinb2

Benzene is a widely used chemical and an environmental pollutant. Exposure to benzene can cause blood diseases, but the mechanisms underlying benzene haematotoxicity have not been fully clarified. Ecotropic virus integration site-1 (Evi1), a transcription factor, plays important roles in normal haematopoiesis and haematological diseases. In this study, we investigated the role and mechanism of Evi1 in benzene-induced haematotoxicity. We found that benzene exposure significantly increased Evi1 level in white blood cells (WBCs) in occupational benzene workers as well as mouse bone marrow cells. Further in vitro results demonstrated that compared with control cells exposed to same 1,4-benzoquinone (1,4-BQ, an important active metabolite of benzene) concentration, Evi1 downregulation significantly reduced cell proliferation, and disrupted cell viability, apoptosis, erythroid and megakaryotic cell differentiation and cell cycle. Additionally, down-regulation of Evi1 suppressed phosphoinositide 3-kinase (PI3K)/mTOR signalling pathway and elevated its target gene Serpinb2 following 1,4-BQ exposure. Moreover, the PI3K activator could partially relieve the inhibitory effect of down-regulation of Evi1 on cell proliferation and increase cell arrest in in G2/M phase. What's more, downregulation of Serpinb2 could partially alleviate proliferation inhibition and reverse cell cycle changes in G0/G1 phase and S phase induced by Evi1 inhibition. In conclusion, our data revealed that Evi1 downregulation aggravated the inhibition of cell proliferation and arrested cells in the G0/G1 phase when exposed to 1,4-BQ, potentially by inactivating the PI3K/mTOR pathway and upregulating downstream target gene Serpinb2. Our study provides novel insights on mechanism by which Evi1 participates in benzene-induced haematotoxicity.

The Crosstalk Between Signaling Pathways and Cancer Metabolism in Colorectal Cancer

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers worldwide. Metabolic reprogramming represents an important cancer hallmark in CRC. Reprogramming core metabolic pathways in cancer cells, such as glycolysis, glutaminolysis, oxidative phosphorylation, and lipid metabolism, is essential to increase energy production and biosynthesis of precursors required to support tumor initiation and progression. Accumulating evidence demonstrates that activation of oncogenes and loss of tumor suppressor genes regulate metabolic reprogramming through the downstream signaling pathways. Protein kinases, such as AKT and c-MYC, are the integral components that facilitate the crosstalk between signaling pathways and metabolic pathways in CRC. This review provides an insight into the crosstalk between signaling pathways and metabolic reprogramming in CRC. Targeting CRC metabolism could open a new avenue for developing CRC therapy by discovering metabolic inhibitors and repurposing protein kinase inhibitors/monoclonal antibodies.

Autocrine signaling by receptor tyrosine kinases in urothelial carcinoma of the bladder

Comprehensive characterizations of bladder cancer (BCa) have established molecular phenotype classes with distinct alterations and survival trends. Extending these studies within the tyrosine kinase (TK) family to identify disease drivers could improve our use of TK inhibitors to treat specific patient groups or individuals. We examined the expression distribution of TKs as a class (n = 89) in The Cancer Genome Atlas (TCGA) muscle invasive BCa data set (n >400). Patient profiles of potentially oncogenic alterations (overexpression and/or amplification) clustered TKs into 3 groups; alterations of group 1 and 3 TKs were associated with significantly worse patient survival relative to those without alterations. Many TK pathways induce epithelial-to-mesenchymal transition (EMT), which promotes tumor invasiveness and metastasis. Overexpression and/or amplification among 9 EMT transcriptional activators occurred in 43% of TCGA cases. Co-occurring alterations of TKs and EMT transcriptional activators involved most group 1 TKs; 24% of these events were associated with significantly worse patient survival. Co-occurring alterations of receptor TKs and their cognate ligands occurred in 16% of TCGA cases and several BCa-derived cell lines. Suppression of GAS6, MST1 or CSF1, or their respective receptors (AXL, MST1R and CSF1R), in BCa cell lines was associated with decreased receptor activation, cell migration, cell proliferation and anchorage independent cell growth. These studies reveal the patterns and prevalence of potentially oncogenic TK pathway-related alterations in BCa and identify specific alterations associated with reduced BCa patient survival. Detection of these features in BCa patients could better inform TK inhibitor use and improve clinical outcomes.

Resveratrol, curcumin, paclitaxel and miRNAs mediated regulation of PI3K/Akt/mTOR pathway: go four better to treat bladder cancer

Bladder cancer (BC) is a leading cause of death among urothelial malignancies that more commonly affect male population. Poor prognosis and resistance to chemotherapy are the two most important characteristics of this disease. PI3K/Akt/mTOR signaling pathway has been considered pivotal in the regulation of proliferation, migration, invasiveness, and metastasis. Deregulation of PI3K/Akt/mTOR signaling has been found in 40% of bladder cancers. Several microRNAs (miRNAs) have been reported to interact with the PI3K/Akt/mTOR signaling pathway with a different possible role in proliferation and apoptosis in bladder cancer. Thus, miRNAs can be used as potential biomarkers for BC. Natural compounds have been in the spotlight for the past decade due to their effective anti-proliferative capabilities. However, little is known of its possible effects in bladder cancer. The aim of this review is to discuss the interplay between PI3K/Akt/mTOR, miRNAs, and natural compounds and emphasize the importance of miRNAs as biomarkers and resveratrol, curcumin and paclitaxel as a possible therapeutic approach against bladder cancer.

Novel antiproliferative agents bearing morpholinopyrimidine scaffold as PI3K inhibitors and apoptosis inducers; design, synthesis and molecular docking

Two series of novel morpholinopyrimidine derivatives were synthesized and screened for their in-vitro cytotoxic activity against 60 tumor cell line by the National Cancer Institute, USA. The in-vitro cytotoxic IC₅₀ values for the most active compounds 6e, 6g, and 6l against the most sensitive cell line leukemia SR were estimated (IC₅₀ = 0.76, 13.59, and 4.37 uM, respectively). To investigate their PI3K enzyme inhibition activity, the assay was done on Class IA (α, β, & δ) isoforms. The IC₅₀ values were very promising: compound [6e = 11.73 (α), 6.09 (β), 11.18 (δ)], compound [6g = 8.43 (α), 15.84 (β), 30.62 (δ)], and compound [6l = 13.98 (α), 7.22 (β), 10.94 (δ)], compared to the reference compound LY294002 = 6.28 (α), 4.51 (β), 4.60 (δ) uM, respectively. Moreover, cell cycle analysis and annexin V-FITC staining were done on Leukemia SR, there was arrest at G2/M phase and apoptosis was induced. Finally, docking study was performed to analyze the interactive mode of these derivatives in PI3Kα ATP-binding site. These outcomes proved that compounds 6e, 6g, and 6l are potential leads for further optimization as antileukemic agents.

Metformin inhibits cervical cancer cell proliferation by modulating PI3K/Akt-induced major histocompatibility complex class I-related chain A gene expression

Background

Recent studies have shown that the classic hypoglycemic drug metformin inhibits tumor growth; however, the underlying mechanism remains unclear. We previously showed that metformin disrupts the sponge effect of long non-coding RNA MALAT1/miR-142-3p to inhibit cervical cancer cell proliferation. In this study, we interrogated the ability of metformin to modulate the anti-tumor immune response in cervical cancer.

Methods

The cell counting kit-8 assay was used to detect the viability of cervical cancer cells. Flow cytometry assays were performed to measure cell apoptosis and cell cycle. Lactate dehydrogenase (LDH) cytotoxicity assay was used to detect NK Cell Cytotoxicity. Relative protein levels were determined by immunoblotting and relative gene levels were determined by quantitative real-time PCR. Tumor Xenograft Modeling was used to evaluate the effect of metformin in vivo.

Results

Metformin inhibited cervical cancer cell proliferation, cervical cancer xenograft growth, expression of PCNA, p-PI3K and p-Akt. Moreover metformin induced cervical cancer cell apoptosis and caused cancer cell cycle arrest. In addition, metformin upregulated the expression of DDR-1 and p53 in human cervical cancer cells. Furthermore, metformin also regulated the mRNA and protein expression of MICA and HSP70 on the surface of human cervical cancer cells via the PI3K/Akt pathway, enhancing NK cell cytotoxicity.

Conclusions

In conclusion, our results suggest that metformin may be used as immunopotentiator to inhibit cervical cancer progression and may be considered a viable candidate for combination therapy with immunotherapy.

Crosstalks of GSK3 signaling with the mTOR network and effects on targeted therapy of cancer

The introduction of therapeutics targeting specific tumor-promoting oncogenic or non-oncogenic signaling pathways has revolutionized cancer treatment. Mechanistic (previously mammalian) target of rapamycin (mTOR), a highly conserved Ser/Thr kinase, is a central hub of the phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR network, one of the most frequently deregulated signaling pathways in cancer, that makes it an attractive target for therapy. Numerous mTOR inhibitors have progressed to clinical trials and two of them have been officially approved as anticancer therapeutics. However, mTOR-targeting drugs have met with a very limited success in cancer patients. Frequently, the primary impediment to a successful targeted therapy in cancer is drug-resistance, either from the very beginning of the therapy (innate resistance) or after an initial response and upon repeated drug treatment (evasive or acquired resistance). Drug-resistance leads to treatment failure and relapse/progression of the disease. Resistance to mTOR inhibitors depends, among other reasons, on activation/deactivation of several signaling pathways, included those regulated by glycogen synthase kinase-3 (GSK3), a protein that targets a vast number of substrates in its repertoire, thereby orchestrating many processes that include cell proliferation and survival, metabolism, differentiation, and stemness. A detailed knowledge of the rewiring of signaling pathways triggered by exposure to mTOR inhibitors is critical to our understanding of the consequences such perturbations cause in tumors, including the emergence of drug-resistant cells. Here, we provide the reader with an updated overview of intricate circuitries that connect mTOR and GSK3 and we relate them to the efficacy (or lack of efficacy) of mTOR inhibitors in cancer cells.

The emergence of drug resistance to targeted cancer therapies: Clinical evidence

For many decades classical anti-tumor therapies included chemotherapy, radiation and surgery; however, in the last two decades, following the identification of the genomic drivers and main hallmarks of cancer, the introduction of therapies that target specific tumor-promoting oncogenic or non-oncogenic pathways, has revolutionized cancer therapeutics. Despite the significant progress in cancer therapy, clinical oncologists are often facing the primary impediment of anticancer drug resistance, as many cancer patients display either intrinsic chemoresistance from the very beginning of the therapy or after initial responses and upon repeated drug treatment cycles, acquired drug resistance develops and thus relapse emerges, resulting in increased mortality. Our attempts to understand the molecular basis underlying these drug resistance phenotypes in pre-clinical models and patient specimens revealed the extreme plasticity and adaptive pathways employed by tumor cells, being under sustained stress and extensive genomic/proteomic instability due to the applied therapeutic regimens. Subsequent efforts have yielded more effective inhibitors and combinatorial approaches (e.g. the use of specific pharmacologic inhibitors with immunotherapy) that exhibit synergistic effects against tumor cells, hence enhancing therapeutic indices. Furthermore, new advanced methodologies that allow for the early detection of genetic/epigenetic alterations that lead to drug chemoresistance and prospective validation of biomarkers which identify patients that will benefit from certain drug classes, have started to improve the clinical outcome. This review discusses emerging principles of drug resistance to cancer therapies targeting a wide array of oncogenic kinases, along with hedgehog pathway and the proteasome and apoptotic inducers, as well as epigenetic and metabolic modulators. We further discuss mechanisms of resistance to monoclonal antibodies, immunomodulators and immune checkpoint inhibitors, potential biomarkers of drug response/drug resistance, along with possible new therapeutic avenues for the clinicians to combat devastating drug resistant malignancies. It is foreseen that these topics will be major areas of focused multidisciplinary translational research in the years to come.

The role of collagen in cancer: from bench to bedside

Collagen is the major component of the tumor microenvironment and participates in cancer fibrosis. Collagen biosynthesis can be regulated by cancer cells through mutated genes, transcription factors, signaling pathways and receptors; furthermore, collagen can influence tumor cell behavior through integrins, discoidin domain receptors, tyrosine kinase receptors, and some signaling pathways. Exosomes and microRNAs are closely associated with collagen in cancer. Hypoxia, which is common in collagen-rich conditions, intensifies cancer progression, and other substances in the extracellular matrix, such as fibronectin, hyaluronic acid, laminin, and matrix metalloproteinases, interact with collagen to influence cancer cell activity. Macrophages, lymphocytes, and fibroblasts play a role with collagen in cancer immunity and progression. Microscopic changes in collagen content within cancer cells and matrix cells and in other molecules ultimately contribute to the mutual feedback loop that influences prognosis, recurrence, and resistance in cancer. Nanoparticles, nanoplatforms, and nanoenzymes exhibit the expected gratifying properties. The pathophysiological functions of collagen in diverse cancers illustrate the dual roles of collagen and provide promising therapeutic options that can be readily translated from bench to bedside. The emerging understanding of the structural properties and functions of collagen in cancer will guide the development of new strategies for anticancer therapy.

Cell-intrinsic survival signals. The role of autophagy in metastatic dissemination and tumor cell dormancy

Metastasis is the main cause of cancer-related deaths. Disseminated tumor cells (DTCs), which seed metastasis, can remain undetected in a dormant state for decades after treatment of the primary tumor and their persistence is the main cause of late relapse and death in a substantial proportion of cancer patients. Understanding the mechanisms underlying the survival of dormant DTCs is of utmost importance to develop new therapies that effectively kill DTCs while in a quiescent state, therefore preventing metastatic disease and minimizing the chance of future relapses. Besides key interactions with the local microenvironment, dormant DTCs must integrate survival mechanisms to remain viable for long periods of time. Here, the pro-survival role of autophagy in tumor cell dissemination and dormant DTC maintenance are discussed, as well as the implications of the current knowledge for future research efforts.

The Evolving Landscape of Cancer Therapeutics

The last 100 years have seen a dramatic alteration in the treatment of cancer. Aside from small molecule inhibitors of protein tyrosine kinases, monoclonal antibodies have also been found to provide valuable therapeutic approaches for modulating tumour pathophysiology. As our knowledge of cancer biology improves, the specificity of this new generation of drugs is generally delivering an improved therapeutic ratio compared to traditional cytotoxic agents. However, patient selection through the use of biomarkers is key in optimising efficacy and improving cost-effectiveness. The most recent wave of revolutionary new systemic therapy approaches to cancer has arrived in recent years in the form of immune checkpoint inhibitors, now clinically validated as modulators of immune-regulatory pathways. The future of oncology therapeutics includes a combination of cytotoxic agents, targeted therapies and immunotherapy.