The evolution of phosphatidylinositol 3-kinases as regulators of growth and metabolism

Unraveling the AKT/ERK cascade and its role in Parkinson disease

Parkinson disease represents a significant and growing burden on global healthcare systems, necessitating a deeper understanding of their underlying molecular mechanisms for the development of effective treatments. The AKT and ERK pathways play crucial roles in the disease, influencing multiple cellular pathways that support neuronal survival. Researchers have made notable progress in uncovering how these pathways are controlled by upstream kinases and how their downstream effects contribute to cell signalling. However, as we delve deeper into their intricacies, we encounter increasing complexity, compounded by the convergence of multiple signalling pathways. Many of their targets overlap with those of other kinases, and they not only affect specific substrates but also influence entire signalling networks. This review explores the intricate interplay of the AKT/ERK pathways with several other signalling cascades, including oxidative stress, endoplasmic reticulum stress, calcium homeostasis, inflammation, and autophagy, in the context of Parkinson disease. We discuss how dysregulation of these pathways contributes to disease progression and neuronal dysfunction, highlighting potential therapeutic targets for intervention. By elucidating the complex network of interactions between the AKT/ERK pathways and other signalling cascades, this review aims to provide insights into the pathogenesis of Parkinson disease and describe the development of novel therapeutic strategies.

Pik3c3 expression profiling in the mouse kidney and its role in proximal tubule cell physiology

The class 3 phosphatidylinositol 3-kinase (Pik3c3) plays critical roles in regulating autophagy, endocytosis, and nutrient sensing, but its expression profile in the kidney remains undefined. Recently, we validated a Pik3c3 antibody through immunofluorescence staining of kidney tissues from cell type-specific Pik3c3 knockout mice. Immunohistochemistry unveiled significant disparities in Pik3c3 expression levels across various kidney cell types. Notably, renal interstitial cells exhibit minimal Pik3c3 expression. Further, coimmunofluorescence staining, utilizing nephron segment- or cell type-specific markers, revealed nearly undetectable levels of Pik3c3 expression in glomerular mesangial cells and endothelial cells. Intriguingly, although podocytes exhibit the highest Pik3c3 expression levels among all kidney cell types, the renal proximal tubule cells (RPTCs) express the highest level of Pik3c3 among all renal tubules. RPTCs are known to express the highest level of the epidermal growth factor receptor (EGFR) in adult kidneys; however, the role of Pik3c3 in EGFR signaling within RPTCs remains unexplored. Therefore, we conducted additional cell culture studies. The results demonstrated that Pik3c3 inhibition significantly delayed EGF-stimulated EGFR degradation and the termination of EGFR signaling in RPTCs. Mechanistically, Pik3c3 inhibition surprisingly did not affect the initial endocytosis process but instead impeded the lysosomal degradation of EGFR. In summary, this study defines, for the first time, the expression profile of Pik3c3 in the mouse kidney and also highlights a pivotal role of Pik3c3 in the proximal tubule cells. These findings shed light on the intricate mechanisms underlying Pik3c3-mediated regulation of EGFR signaling, providing valuable insights into the role of Pik3c3 in renal cell physiology. NEW & NOTEWORTHY This is the first report defining the class 3 phosphatidylinositol 3-kinase (Pik3c3) expression profile in the kidney. Pik3c3 is nearly absent in renal interstitial cells, glomerular mesangial cells, and endothelial cells. Remarkably, glomerular podocytes express the highest Pik3c3 level in the kidney. However, the proximal tubule exhibits the highest expression level among all renal tubules. This study also unveils the pivotal role of Pik3c3 in regulating EGFR degradation and signaling termination in RPTCs, furthering our understanding of Pik3c3 in renal cell physiology.

Targeting the RAS upstream and downstream signaling pathway for cancer treatment

Cancer often involves the overactivation of RAS/RAF/MEK/ERK (MAPK) and PI3K-Akt-mTOR pathways due to mutations in genes like RAS, RAF, PTEN, and PIK3CA. Various strategies are employed to address the overactivation of these pathways, among which targeted therapy emerges as a promising approach. Directly targeting specific proteins, leads to encouraging results in cancer treatment. For instance, RTK inhibitors such as imatinib and afatinib selectively target these receptors, hindering ligand binding and reducing signaling initiation. These inhibitors have shown potent efficacy against Non-Small Cell Lung Cancer. Other inhibitors, like lonafarnib targeting Farnesyltransferase and GGTI 2418 targeting geranylgeranyl Transferase, disrupt post-translational modifications of proteins. Additionally, inhibition of proteins like SOS, SH2 domain, and Ras demonstrate promising anti-tumor activity both in vivo and in vitro. Targeting downstream components with RAF inhibitors such as vemurafenib, dabrafenib, and sorafenib, along with MEK inhibitors like trametinib and binimetinib, has shown promising outcomes in treating cancers with BRAF-V600E mutations, including myeloma, colorectal, and thyroid cancers. Furthermore, inhibitors of PI3K (e.g., apitolisib, copanlisib), AKT (e.g., ipatasertib, perifosine), and mTOR (e.g., sirolimus, temsirolimus) exhibit promising efficacy against various cancers such as Invasive Breast Cancer, Lymphoma, Neoplasms, and Hematological malignancies. This review offers an overview of small molecule inhibitors targeting specific proteins within the RAS upstream and downstream signaling pathways in cancer.

Identification of new subtypes of breast cancer based on vasculogenic mimicry related genes and a new model for predicting the prognosis of breast cancer

Breast cancer is a malignant tumor that poses a serious threat to women's health, and vasculogenic mimicry (VM) is strongly associated with bad prognosis in breast cancer. However, the relationship between VM and immune infiltration in breast cancer and the underlying mechanisms have not been fully studied. On the basis of the Cancer Genome Atlas (TCGA), Fudan University Shanghai Cancer Center (FUSCC) database, GSCALite database, and gene set enrichment analysis (GSEA) datasets, we investigated the potential involvement of VM-related genes in the development and progression of breast cancer. We analyzed the differential expression, mutation status, methylation status, drug sensitivity, tumor mutation burden (TMB), microsatellite instability (MSI), immune checkpoints, tumor microenvironment (TME), and immune cell infiltration levels associated with VM-related genes in breast cancer. We created two VM subclusters out of breast cancer patients using consensus clustering, and discovered that patients in Cluster 1 had better survival outcomes compared to those in Cluster 2. The infiltration levels of T cells CD4 memory resting and T cells CD8 were higher in Cluster 1, indicating an immune-active state in this cluster. Additionally, we selected three prognostic genes (LAMC2, PIK3CA, and TFPI2) using Lasso, univariate, and multivariate Cox regression and constructed a risk model, which was validated in an external dataset. The prognosis of patients is strongly correlated with aberrant expression of VM-related genes, which advances our knowledge of the tumor immune milieu and enables us to identify previously unidentified breast cancer subtypes. This could direct more potent immunotherapy approaches.

miR-155 enhances apoptosis of macrophage through suppressing PI3K-AKT activation in Pseudomonas aeruginosa keratitis

Keratitis induced by Pseudomonas aeruginosa (P. aeruginosa) is an acute and serious corneal inflammation. As a family of gene regulators, miRNAs play a crucial role in modulating host response after microbial invasion. However, their functions in P. aeruginosa keratitis remain largely unclear. In the present study, we demonstrated that miR-155 expression was significantly increased in macrophages and corneal tissue after P. aeruginosa infection. In vivo studies demonstrated that mice with miR-155 knockdown displayed more resistance to P. aeruginosa keratitis, with a lower bacterial burden. In addition, in vitro and in vivo studies indicated that miR-155 enhanced apoptosis of macrophages after P. aeruginosa infection, and resulted in a susceptible phenotype of P. aeruginosa keratitis. Moreover, miR-155 induced apoptosis through reducing activation of PI3K-Akt signaling pathway. Our data provided evidence of miR-155 mediated apoptosis of macrophage in P. aeruginosa keratitis, which may be an underlying target for the therapy of P. aeruginosa keratitis and other infectious diseases.

Signaling effect, combinations, and clinical applications of triciribine

Triciribine (TCN) is a tricyclic nucleoside. Its synthesis was first described in 1971. Subsequent studies have indicated that TCN plays a role in inhibiting DNA synthesis and was revealed to possess a higher selectivity for Akt. Although a single dose of TCN demonstrated limited activity in solid tumors at the clinical level, combinations of TCN with various agents, such as specific inhibitors, tyrosine kinase inhibitor dasatinib, ErbB inhibitor tipifarnib, IGF1-R inhibitor NVP-AEW541, mTORC1 inhibitor RAD-001, TNF-related apoptosis-inducing ligand, PPARγ agonist, 1,25(OH)2D3, gemcitabine, and paclitaxel, have been reported to be efficient against various malignancies such as pancreatic, breast, prostate cancer, insulinoma, gut neuroendocrine tumor, and hepatocellular carcinoma at the preclinical level. Other than malignancies, through Akt inhibition activity, TCN has also been demonstrated potential for treating lung injuries, including those encountered in COVID-19 infections.

Icaritin attenuates ischemia-reperfusion injury by anti-inflammation, anti-oxidative stress, and anti-autophagy in mouse liver

BACKGROUND

Hepatic ischemia-reperfusion (IR) injury is a major complication of liver transplantation and gravely affects patient prognosis. Icaritin (ICT), the primary plasma metabolite of icariin (ICA), plays a critical role in anti-inflammatory and immunomodulatory processes. However, the role of ICT in hepatic IR injury remains largely undefined. In this study, we aimed to elucidate the role of ICT in hepatic IR injury.

METHODS

We established hepatic IR injury models in animals, as well as an oxygen-glucose deprivation/reperfusion (OGD/R) cell model. Liver injury in vivo was assessed by measuring serum alanine aminotransferase (ALT) levels, necrotic areas by liver histology and local hepatic inflammatory responses. For in vitro analyses, we implemented flow-cytometric and western blot analyses, transmission electron microscopy, and an mRFP-GFP-LC3 adenovirus reporter assay to assess the effects of ICT on OGD/R injury in AML12 and THLE-2 cell lines. Signaling pathways were explored in vitro and in vivo to identify possible mechanisms underlying ICT action in hepatic IR injury.

RESULTS

Compared to the mouse model group, ICT preconditioning considerably protected the liver against IR stress, and diminished the levels of necrosis/apoptosis and inflammation-related cytokines. In additional studies, ICT treatment dramatically boosted the expression ratios of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR proteins in hepatic cells following OGD/R damage. We also applied LY294002 (a PI3K inhibitor) and RAPA (rapamycin, an mTOR inhibitor), which blocked the protective effects of ICT in hepatocytes subjected to OGD/R.

CONCLUSION

This study indicates that ICT attenuates ischemia-reperfusion injury by exerting anti-inflammation, anti-oxidative stress, and anti-autophagy effects, as demonstrated in mouse livers. We thus posit that ICT could have therapeutic potential for the treatment of hepatic IR injury.

A transcriptome-wide analysis provides novel insights into how Metabacillus indicus promotes coral larvae metamorphosis and settlement

BACKGROUND

Coral reefs experience frequent and severe disturbances that can overwhelm their natural resilience. In such cases, ecological restoration is essential for coral reef recovery. Sexual reproduction has been reported to present the simplest and most cost-effective means for coral reef restoration. However, larval settlement and post-settlement survival represent bottlenecks for coral recruitment in sexual reproduction. While bacteria play a significant role in triggering coral metamorphosis and settlement in many coral species, the underlying molecular mechanisms remain largely unknown. In this study, we employed a transcriptome-level analysis to elucidate the intricate interactions between bacteria and coral larvae that are crucial for the settlement process.

RESULTS

High Metabacillus indicus strain cB07 inoculation densities resulted in the successful induction of metamorphosis and settlement of coral Pocillopora damicoris larvae. Compared with controls, inoculated coral larvae exhibited a pronounced increase in the abundance of strain cB07 during metamorphosis and settlement, followed by a significant decrease in total lipid contents during the settled stage. The differentially expressed genes (DEGs) during metamorphosis were significantly enriched in amino acid, protein, fatty acid, and glucose related metabolic pathways. In settled coral larvae induced by strain cB07, there was a significant enrichment of DEGs with essential roles in the establishment of a symbiotic relationship between coral larvae and their symbiotic partners. The photosynthetic efficiency of strain cB07 induced primary polyp holobionts was improved compared to those of the negative controls. In addition, coral primary polyps induced by strain cB07 showed significant improvements in energy storage and survival.

CONCLUSIONS

Our findings revealed that strain cB07 can promote coral larval settlement and enhance post-settlement survival and fitness. Manipulating coral sexual reproduction with strain cB07 can overcome the current recruitment bottleneck. This innovative approach holds promise for future coral reef restoration efforts.

Development of the telescoped flow Pd-catalyzed aerobic alcohol oxidation/reductive amination sequence in the synthesis of new phosphatidylinositide 3-kinase inhibitor (CPL302415)

Herein, we describe a two-step sequential flow synthesis: Pd-catalyzed aerobic oxidation to an aldehyde 2, which is then converted by reductive amination in H-Cube® PRO into CPL302415 (3). CPL302415 is our new PI3Kδ inhibitor, which is now under evaluation for the treatment of systemic lupus erythematosus. The process was optimized using the DoE approach and generalized to other biologically active derivatives of CPL302415.

Gene co-expression network analysis for porcine intramuscular fatty acid composition

In pigs, meat quality depends markedly on the fatty acid (FA) content and composition of the intramuscular fat, which is partly determined by the gene expression in this tissue. The aim of this work was to identify the link between muscle gene expression and its FA composition. In an (Iberian × Duroc) × Duroc backcrossed pig population, we identified modules of co-expressed genes, and correlation analyses were performed for each of them versus the phenotypes, finding four relevant modules. Two of the modules were positively correlated with saturated FAs (SFAs) and monounsaturated FAs (MUFAs), while negatively correlated with polyunsaturated FAs (PUFAs) and the omega-6/omega-3 ratio. The gene-enrichment analysis showed that these modules had over-representation of pathways related with the biosynthesis of unsaturated FAs, the Peroxisome proliferator-activated receptor signalling pathway and FA elongation. The two other relevant modules were positively correlated with PUFA and the n-6/n-3 ratio, but negatively correlated with SFA and MUFA. In this case, they had an over-representation of pathways related with fatty and amino acid degradation, and with oxidative phosphorylation. Using a graphical Gaussian model, we inferred a network of connections between the genes within each module. The first module had 52 genes with 87 connections, and the most connected genes were ADIPOQ, which is related with FA oxidation, and ELOVL6 and FABP4, both involved in FA metabolism. The second module showed 196 genes connected by 263 edges, being FN1 and MAP3K11 the most connected genes. On the other hand, the third module had 161 genes connected by 251 edges and ATG13 was the top neighbouring gene, while the fourth module had 224 genes and 655 connections, and its most connected genes were related with mitochondrial pathways. Overall, this work successfully identified relevant muscle gene networks and modules linked with FA composition, providing further insights on how the physiology of the pigs influences FA composition.

A common variant in PIK3CG gene associated with the prognosis of heart failure

Phosphoinositide 3-kinase γ (PI3Kγ) is G-protein-coupled receptor-activated lipid kinase with both kinase-dependent and kinase-independent activity. Plenty of evidence have demonstrated that PI3Kγ participated in TAC and I/R-induced myocardial remodelling and heart failure (HF). In this study, we tested the hypothesis that common variants in the PI3Kγ gene (PIK3CG) were associated with the prognosis of HF in the Chinese Han population. Through re-sequencing and genotyping, we finally identified a common variant in the 3'UTR of PIK3CG strongly associated with the prognosis of HF in two-stage population: adjusted p = 0.007, hazard ratio = 0.56 (0.36-0.85) in the first cohort and adjusted p = 0.024, hazard ratio = 0.39 (0.17-0.88) in the replicated cohort. A series of functional assays revealed that rs10215499-A allele suppressed PIK3CG translation by facilitating has-miR-133a-3p binding, but not the G allele. Subjects carrying the GG genotype showed higher mRNA and protein level than those with AA and AG genotype. Furthermore, overexpression of PIK3CG could protect AC16 from hypoxia/reoxygenation (H/R)-induced apoptosis, while the case was opposite for PIK3CG silencing. In conclusion, common variant rs10215499 in the 3'-UTR of PIK3CG might affect the prognosis of HF by interfering with miR-133a-3p binding and PIK3CG is a promising target for HF treatment in the future.

Phase II Study of Samotolisib in Children and Young Adults With Tumors Harboring Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Pathway Alterations: Pediatric MATCH APEC1621D

PURPOSE

Patients age 1-21 years with relapsed or refractory solid and CNS tumors were assigned to phase II studies of molecularly targeted therapies on the National Cancer Institute-Children's Oncology Group (NCI-COG) Pediatric Molecular Analysis for Therapy Choice (MATCH) trial. Patients whose tumors harbored predefined genetic alterations in the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway and lacked mitogen-activated protein kinase pathway activating alterations were treated with the PI3K/mTOR inhibitor samotolisib.

METHODS

Patients received samotolisib twice daily in 28-day cycles until disease progression or unacceptable toxicity. A rolling 6 limited dose escalation was performed as, to our knowledge, this was the first pediatric study of samotolisib. The primary end point was the objective response rate; secondary end points included progression-free survival (PFS) and the recommended phase II dose and toxicity of samotolisib in children.

RESULTS

A total of 3.4% (41/1,206) of centrally tested patients were matched to this arm. Seventeen patients were treated. Among treated patients, the most common diagnoses included osteosarcoma (n = 6) and high-grade glioma (n = 5) harboring alterations in phosphatase and tensin homolog (n = 6), PIK3CA (n = 5), and tuberous sclerosis complex 2 (n = 3). No objective responses or prolonged stable disease were observed. Three-month PFS was 12% (95% CI, 2 to 31). Two patients experienced dose-limiting toxicities (mucositis and pneumonitis). Dose level 2 (115 mg/m2/dose twice daily) was determined to be the recommended phase II dose of samotolisib in children.

CONCLUSION

This nationwide study was successful at identifying patients and evaluating the efficacy of molecularly targeted therapy for rare molecular subgroups of patients in a histology-agnostic fashion. Unfortunately, there was no activity of samotolisib against tumors with PI3K/mTOR pathway alterations. Prospective trials such as the NCI-COG Pediatric MATCH are necessary to evaluate the efficacy of molecularly targeted therapies given their increasing use in clinical practice.

Aggressive pituitary tumors and carcinomas: medical treatment beyond temozolomide

Aggressive pituitary tumors are a subset of pituitary neoplasms, characterized by unusually fast growth rate, invasiveness and overall resistance to optimized standard treatment. When metastases are present, the term pituitary carcinoma is employed. After failure of standard treatments, current guidelines recommend first-line temozolomide monotherapy. However, a significant number of patients do not respond to temozolomide, or experience disease progression following its discontinuation; in these latter cases, re-challenge with temozolomide is generally advised, although the reported outcomes have been less satisfactory. Although no alternative therapies have been formally recommended after temozolomide failure, growing evidence regarding potential second- or third-line therapeutic strategies has emerged. In the present work, we reviewed the available evidence published up to April 2023 involving the most relevant therapies employed so far, namely immune checkpoint inhibitors, bevacizumab, peptide radionuclide receptor therapy, tyrosine kinase inhibitors and mTOR inhibitors. For each treatment, we report efficacy and safety outcomes, along with data regarding potential predictors of response. Overall, immune checkpoint inhibitors and bevacizumab are showing the most promise as therapeutic options after temozolomide failure. The former showed better responses in pituitary carcinomas. Peptide radionuclide receptor therapy has also showed some efficacy in these tumors, while tyrosine kinase inhibitors and mTOR inhibitors have exhibited so far limited or no efficacy. Further studies, as well as an individualized, patient-tailored approach, are clearly needed. In addition, we report an unpublished case of a silent corticotroph pituitary carcinoma that progressed under dual immunotherapy, and then showed stable disease under a combination of lomustine and bevacizumab.

Quantitative characterization of the effects of fulvestrant alone or in combination with taselisib (PI3Kinase inhibitor) on longitudinal tumor growth in patients with estrogen receptor-positive, HER2-negative, PIK3CA-mutant, advanced or metastatic breast cancer

PURPOSE

Among cases of breast cancer, estrogen receptor-positive (ER +), PIK3CA-mutant, HER2- advanced breast cancer stands as a particularly complex clinical indication where approximately 40% of ER + /HER2- breast carcinomas present mutations in the PIK3CA gene. A significant hurdle in treating ER + breast cancer lies in surmounting the challenges of endocrine resistance. In the clinical setting, a multifaceted approach is essential for this indication, one that not only explores the effectiveness of individual treatments but also delves into the potential gains in therapeutic outcome from combination therapies.

METHODS

In the current study, longitudinal tumor growth inhibition (TGI) models were developed to characterize tumor response over time in postmenopausal women with ER + /HER2- advanced or metastatic breast cancer undergoing treatment with fulvestrant alone or in combination with the PI3K inhibitor, taselisib. Impact of clinically relevant covariates on TGI metrics was assessed to identify patient subsets most likely to benefit from treatment with fulvestrant monotherapy or combination with taselisib.

RESULTS

Tumor growth rate constant (Kg) was found to increase with increasing baseline tumor size and in the absence of baseline endocrine sensitivity. Further, Kg decreased in the absence of baseline liver metastases both in fulvestrant monotherapy and combination therapy with taselisib. Overall, additive/potentially synergistic anti-tumor effects were observed in patients treated with the taselisib-fulvestrant combination.

CONCLUSION

These results have important implications for understanding the therapeutic impact of combination treatment approaches and individualized responses to these treatments. Finally, this work, emphasizes the importance of model informed drug development for targeted cancer therapy.

CLINICAL TRIAL REGISTRATION

NCT02340221 Registered January 16, 2015, NCT01296555 Registered February 14, 2011.

Functional characterization of PI3K C2 domain mutations detected in breast cancer circulating tumor cells and metastatic cells

BACKGROUND

In breast cancer, over one third of all patients harbor a somatic mutation in the PIK3CA gene, encoding the p110α catalytic subunit of the phosphatidylinositol 3-kinase (PI3K) in their tumor cells. Circulating tumor cells (CTCs) are cells shed from the primary tumor into the blood stream. Recently, the long-term stable breast cancer CTC-ITB-01 cell line with tumorigenic and metastatic capacity was established from liquid biopsy derived cells. The oncogenic hotspot PIK3CA mutation H1047R (kinase domain) was detected in the primary tumor, CTCs and metastasis of the same patient. Other PIK3CA mutations located within the C2 domain (E418K and E453K) were detected in the CTCs and the vaginal metastasis but not in the primary tumor. The goal of our study was to functionally characterize the impact of the rare E418K and E453K mutations within the C2 domain that were not detected in the primary tumor.

METHODS

PIK3CA mutations E418K, E453K, H1047R were generated by site-directed mutagenesis and stably overexpressed in breast cancer cells by lentiviral transduction. Subsequent signaling pathway activation was examined by western blot analysis. The impact of PIK3CA mutations on biological processes was studied by live cell imaging using the Incucyte Zoom system. Structural modeling was conducted in Pymol. The membrane localization of the mutants was evaluated by separating the cytosolic and membrane fraction using ultracentrifugation. Drug susceptibility of CTC-ITB-01 cells was analyzed by live cell imaging.

RESULTS

Western blot analysis of human MDA-MB-231, MCF-7 and T47D breast cancer cells stably overexpressing either the PIK3CA wildtype (WT) or one of the E418K, E453K or H1047R mutants revealed a significant increase in AKT phosphorylation in both C2 mutants (E418K and E453K) and the kinase domain mutant H1047R. Functional analysis showed a significantly increased proliferation of MDA-MB-231 cells overexpressing the E453K and H1047R mutants. Migration was increased in all cells overexpressing WT and each of the mutants. Interestingly, invasion and chemotaxis were only enhanced in the MDA-MB-231 cells overexpressing the C2 domain mutants, i.e. E418K and E453K. In addition, membrane localization of the two C2 domain mutants was increased. Structural modeling of the E453K mutation suggests a disruption of the interaction between the negative regulatory domain of the p85α subunit and the p110α catalytic subunit as a potential mechanism leading to the observed activation of PI3K/AKT/mTOR signaling. Dual targeting of AKT/mTOR pathway by MK2206 and RAD001 leads to very strong synergistic effects (IC50 MK2206: 148 nM, IC50 RAD001: 15 nM) with respect to proliferation in the CTC-ITB-01 line through apoptosis induction.

CONCLUSIONS

Our results demonstrate that PIK3CA C2 domain mutations activate PI3K downstream AKT signaling and can increase proliferation, migration and invasion after stable lentiviral transduction. Although both investigated mutations - E418K and E453K - are located within the C2 domain, a different molecular mechanism can be proposed. The PIK3CA mutated CTC-ITB-01 shows a high susceptibility against dual inhibition of AKT/mTOR. Further studies are required to fully elucidate the oncogenic potential of rare PIK3CA mutations.

Asiaticoside protected brain injury in hypertensive intracerebral hemorrhage via activation of the PI3K/AKT pathway

Hypertensive intracerebral hemorrhage (HICH) is a destructive disease with high mortality, incidence, and disability. Asiaticoside (AC) is a triterpenoid derivative that has demonstrated to exert a protective effect on neuron and blood vessel. To investigate the function and potential mechanism of AC on HICH. Human brain microvascular endothelial cells (hBMECs) were treated with 20 U/mL thrombin for 24 h to establish the HICH model in vitro, and AC with the concentration of 1, 2 and 4 µM were used to incubate hBMECs. The effect and potential mechanism of AC on HICH were investigated by using cell counting kit-8, flow cytometry, tube forming assays, vascular permeability experiments and western blot assays. In vivo, rats were injected with 20 µL hemoglobin with a concentration of 150 mg/mL, and then intragastrically administrated with 1.25, 2.5 and 5 mg/kg AC. Behavioral tests, brain water content measurement, hematoxylin-eosin (HE) staining, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling assays, and western blot were used to assess the effect and potential mechanism of AC on HICH. AC (at 2 and 4 µM) improved the proliferation, apoptosis, angiogenesis and vascular permeability in thrombin-induced hBMECs (p < 0.05). Besides, AC (2.5 and 5 mg/kg) ameliorated behavioral scores, brain water content, pathological lesion, apoptosis and the expression of vascular permeability-related proteins in rats with HICH (p < 0.05). In addition, AC elevated the expression of PI3K/AKT pathway after HICH both in cell and animal models (p < 0.05). Application of LY294002, an inhibitor of PI3K/AKT pathway, reversed the ameliorative effect of AC on the proliferation, apoptosis, angiogenesis and vascular permeability in thrombin-induced hBMECs (p < 0.05). AC reduced brain damage by increasing the expression of the PI3K/AKT pathway after HICH.

Genipin promotes the apoptosis and autophagy of neuroblastoma cells by suppressing the PI3K/AKT/mTOR pathway

This study investigated the underlying function and mechanism of genipin in neuroblastoma (NB). Using flow cytometry analysis and cytotoxicity tests, in vitro studies were conducted to assess the effects of genipin on the SK-N-SH cell line. The mechanism of action of genipin was explored through immunofluorescence staining, Western blotting, and caspase-3 activity assays. In addition, we also created a xenograft tumour model to investigate the effects of genipin in vivo. This research confirmed that genipin suppressed cell viability, induced apoptosis, and promoted autophagy, processes that are likely linked to the inhibition of the PI3K/AKT/mTOR signalling pathway. Autophagy inhibition increases the sensitivity of SK-N-SH cells to genipin. Furthermore, combination treatment with a PI3K inhibitor enhanced the therapeutic efficacy of genipin. These results highlight the potential of genipin as a candidate drug for the treatment of NB.

Diagnosis and Management of Aggressive/Refractory Growth Hormone-Secreting Pituitary Neuroendocrine Tumors

The majority of acromegaly and gigantism are caused by growth hormone-secreting pituitary neuroendocrine tumors (PitNETs). Most cases can be cured or controlled by surgery, medical therapy, and/or radiotherapy. However, a few of these tumors are resistant to traditional therapy and always have a poor prognosis. The title aggressive/refractory is used to differentiate them from pituitary carcinomas. To date, there is no definitive conclusion on how to diagnose aggressive/refractory growth hormone-secreting PitNETs, which may have slowed the process of exploring new therapeutical strategies. We summarized the literature described diagnosis and treatment of the disease. Potential disease markers and prospective therapies were also included.

Design, synthesis and biological evaluation of a novel PSMA-PI3K small molecule drug conjugate

Small molecule drug conjugates are an emerging targeted therapy for cancer treatment. Building upon the overexpressed prostate-specific membrane antigen (PSMA) in prostate cancer, we herein report the design and synthesis of a novel PSMA-PI3K small molecule drug conjugate 1. Conjugate 1 demonstrates potent inhibition against PI3K with an IC50 value of 0.40 nM and simultaneously targets PSMA, giving rise to selective growth inhibition activity for PSMA-positive cancer cells. Conjugate 1 also potently inhibits the phosphorylation of PI3K main downstream effectors and arrests the cell cycle in the G0/G1 phase in PSMA-positive 22Rv1 prostate cancer cells. Further in vivo evaluation shows that conjugate 1 has favorable efficacy and tolerability in a 22Rv1 xenograft model, demonstrating its potential application in targeted cancer therapy.

Iron-dependent KDM4D activity controls the quiescence-activity balance of MSCs via the PI3K-Akt-Foxo1 pathway

Iron deficiency is a prevalent nutritional deficit associated with organ damage and dysfunction. Recent research increasingly associates iron deficiency with bone metabolism dysfunction, although the precise underlying mechanisms remain unclear. Some studies have proposed that iron-dependent methylation-erasing enzyme activity regulates cell proliferation and differentiation under physiological or pathological conditions. However, it remains uncertain whether iron deficiency inhibits the activation of quiescent mesenchymal stem cells (MSCs) by affecting histone demethylase activity. In our study, we identified KDM4D as a key player in the activation of quiescent MSCs. Under conditions of iron deficiency, the H3K9me3 demethylase activity of KDM4D significantly decreased. This alteration resulted in increased heterochromatin with H3K9me3 near the PIK3R3 promoter, suppressing PIK3R3 expression and subsequently inhibiting the activation of quiescent MSCs via the PI3K-Akt-Foxo1 pathway. Iron-deficient mice displayed significantly impaired bone marrow MSCs activation and decreased bone mass compared to normal mice. Modulating the PI3K-Akt-Foxo1 pathway could reverse iron deficiency-induced bone loss.

PRRSV hijacks DDX3X protein and induces ferroptosis to facilitate viral replication

Porcine reproductive and respiratory syndrome virus (PRRSV) is a severe disease with substantial economic consequences for the swine industry. The DEAD-box helicase 3 (DDX3X) is an RNA helicase that plays a crucial role in regulating RNA metabolism, immunological response, and even RNA virus infection. However, it is unclear whether it contributes to PRRSV infection. Recent studies have found that the expression of DDX3X considerably increases in Marc-145 cells when infected with live PRRSV strains Ch-1R and SD16; however, it was observed that inactivated viruses did not lead to any changes. By using the RK-33 inhibitor or DDX3X-specific siRNAs to reduce DDX3X expression, there was a significant decrease in the production of PRRSV progenies. In contrast, the overexpression of DDX3X in host cells substantially increased the proliferation of PRRSV. A combination of transcriptomics and metabolomics investigations revealed that in PRRSV-infected cells, DDX3X gene silencing severely affected biological processes such as ferroptosis, the FoxO signalling pathway, and glutathione metabolism. The subsequent transmission electron microscopy (TEM) imaging displayed the typical ferroptosis features in PRRSV-infected cells, such as mitochondrial shrinkage, reduction or disappearance of mitochondrial cristae, and cytoplasmic membrane rupture. Conversely, the mitochondrial morphology was unchanged in DDX3X-inhibited cells. Furthermore, silencing of the DDX3X gene changed the expression of ferroptosis-related genes and inhibited the virus proliferation, while the drug-induced ferroptosis inversely promoted PRRSV replication. In summary, these results present an updated perspective of how PRRSV infection uses DDX3X for self-replication, potentially leading to ferroptosis via various mechanisms that promote PRRSV replication.

The essential roles of lncRNAs/PI3K/AKT axis in gastrointestinal tumors

The role of long noncoding RNA (lncRNA) in tumors, particularly in gastrointestinal tumors, has gained significant attention. Accumulating evidence underscores the interaction between various lncRNAs and diverse molecular pathways involved in cancer progression. One such pivotal pathway is the PI3K/AKT pathway, which serves as a crucial intracellular mechanism maintaining the balance among various cellular physiological processes for normal cell growth and survival. Frequent dysregulation of the PI3K/AKT pathway in cancer, along with aberrant activation, plays a critical role in driving tumorigenesis. LncRNAs modulate the PI3K/AKT signaling pathway through diverse mechanisms, primarily by acting as competing endogenous RNA to regulate miRNA expression and associated genes. This interaction significantly influences fundamental biological behaviors such as cell proliferation, metastasis, and drug resistance. Abnormal expression of numerous lncRNAs in gastrointestinal tumors often correlates with clinical outcomes and pathological features in patients with cancer. Additionally, these lncRNAs influence the sensitivity of tumor cells to chemotherapy in multiple types of gastrointestinal tumors through the abnormal activation of the PI3K/AKT pathway. These findings provide valuable insights into the mechanisms underlying gastrointestinal tumors and potential therapeutic targets. However, gastrointestinal tumors remain a significant global health concern, with increasing incidence and mortality rates of gastrointestinal tumors over recent decades. This review provides a comprehensive summary of the latest research on the interactions of lncRNA and the PI3K/AKT pathway in gastrointestinal tumor development. Additionally, it focuses on the functions of lncRNAs and the PI3K/AKT pathway in carcinogenesis, exploring expression profiles, clinicopathological characteristics, interaction mechanisms with the PI3K/AKT pathway, and potential clinical applications.

Combined targeted therapy with PI3K and CDK4/6, or FGFR inhibitors show synergistic effects in a neuroblastoma spheroid culture model

AIM

Neuroblastoma (NB) is, in spite of current intensive therapy with severe side effects, still not cured so new therapies are needed. Recently, we showed combining phosphoinositide 3-kinase (PI3K) (BYL719), fibroblast growth factor receptor (FGFR) (JNJ-42756493) and cyclin-dependent kinase 4/6 (CDK4/6) (PD-0332991) inhibitors, in vitro in NB cell lines grown as monolayers had synergistic effects. However, there were variations depending on the combinations used and the targeted NB cell lines. To obtain further information and to mimic more natural circumstances, we investigated the effects of single and combined administrations of the above inhibitors in spheroid NB-cultures.

MATERIAL AND METHODS

Spheroid cultures of NB cell lines SK-N-AS, SK-N-BE(2)-C, SK-N-FI and SK-N-SH were established and treated with single and combined administrations of BYL719, JNJ-42756493, and PD-0332991 and followed for growth, viability, proliferation, cytotoxicity and migration.

KEY FINDINGS

Single inhibitor administrations gave dose dependent responses with regard to growth and viability and their combinations were efficient and resulted in a range of additive and synergistic effects. The responses to individual drugs and their various combinations were predominantly alike regardless of whether the cells were cultivated in monolayer or D spheroid NB models. However, in general, slightly higher drug concentrations were necessary in spheroidcultures.

SIGNIFICANCE

This study provides pre-clinical evidence that single PI3K, FGFR, and CDK4/6, inhibitors exhibit promising anti-NB activity and when combined lower doses of the drugs could be also used in spheroid NB-cultures, supporting the pursuit of further in vitro and in vivo studies in preparation for future potential clinical use.

A deep learning-based theoretical protocol to identify potentially isoform-selective PI3Kα inhibitors

Phosphoinositide 3-kinase alpha (PI3Kα) is one of the most frequently dysregulated kinases known for their pivotal role in many oncogenic diseases. While the side effects linked to existing drugs against PI3Kα-induced cancers provide an avenue for further research, the significant structural conservation among PI3Ks makes it extremely difficult to develop new isoform-selective PI3Kα inhibitors. Embracing this challenge, we herein designed a hybrid protocol by integrating machine learning (ML) with in silico drug-designing strategies. A deep learning classification model was developed and trained on the physicochemical descriptors data of known PI3Kα inhibitors and used as a screening filter for a database of small molecules. This approach led us to the prediction of 662 compounds showcasing appropriate features to be considered as PI3Kα inhibitors. Subsequently, a multiphase molecular docking was applied to further characterize the predicted hits in terms of their binding affinities and binding modes in the targeted cavity of the PI3Kα. As a result, a total of 12 compounds were identified whereas the best poses highlighted the efficiency of these ligands in maintaining interactions with the crucial residues of the protein to be targeted for the inhibition of associated activity. Notably, potential activity of compound 12 in counteracting PI3Kα function was found in a previous in vitro study. Following the drug-likeness and pharmacokinetic characterizations, six compounds (compounds 1, 2, 3, 6, 7, and 11) with suitable ADME-T profiles and promising bioavailability were selected. The mechanistic studies in dynamic mode further endorsed the potential of identified hits in blocking the ATP-binding site of the receptor with higher binding affinities than the native inhibitor, alpelisib (BYL-719), particularly the compounds 1, 2, and 11. These outcomes support the reliability of the developed classification model and the devised computational strategy for identifying new isoform-selective drug candidates for PI3Kα inhibition.

Effect of elastin on abnormal proliferation of pulmonary artery smooth muscle cells at an early stage of hypoxic exposure

Elastin (Eln) is an extracellular matrix protein implicated in the proliferation of vascular smooth muscle cells. However, its potential role in hypoxic pulmonary hypertension (HPH) remains uncertain. This study is the first to demonstrate that elastin can promote the proliferation of mouse pulmonary artery smooth muscle cells (mPASMCs) and that hypoxia significantly induces Eln expression in cultured mPASMCs, thereby participating in the cell cycle. Interference with Eln expression via siRNA led to the downregulation of PCNA, Cyclin A, and Cyclin D, thus, the hypoxia-induced proliferation of mPASMCs was reversed. Furthermore, our study demonstrated that the hypoxia-induced expression of Eln and the proliferation of mPASMCs are associated with the proliferation-related phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. In conclusion, these data suggest that Eln is a key regulatory factor in mPASMCs proliferation, potentially elucidating the mechanism underlying hypoxia-induced mPASMCs proliferation. This finding may offer valuable insights for the study of hypoxic pulmonary hypertension.

A comprehensive review on phosphatidylinositol-3-kinase (PI3K) and its inhibitors bearing pyrazole or indazole core for cancer therapy

Cancer is a complex and multifaceted group of diseases with a high mortality rate characterized by uncontrolled proliferation of abnormal cells. Dysregulation of normal signalling pathways in cancer contributes to the different hallmarks of this disease. The signalling pathway of which phosphatidylinositol 3-kinase (PI3K) is a part is not an exception. In fact, dysregulated activation of PI3K signalling pathways can result in unbridled cellular proliferation and enhanced cell survival, thereby fostering the onset and advancement of cancer. Therefore, there is substantial interest in developing targeted therapies specifically aimed at inhibiting the PI3K enzyme and its associated pathways. Also, the therapeutic interest on pyrazoles and indazoles has been growing due to their various medicinal properties, namely, anticancer activity. Derivatives of these compounds have been studied as PI3K inhibitors, and they showed promising results. There are already some PI3K inhibitors approved by Food and Drug Administration (FDA), such as Idelalisib (Zydelig®) and Alpelisib (Piqray®). In this context, this review aims to address the importance of PI3K in cellular processes and its role in cancer. Additionally, it aims to report a comprehensive literature review of PI3K inhibitors, containing the pyrazole and indazole scaffolds, published in the last fifteen years, focusing on structure-activity relationship aspects, thus providing important insights for the design of novel and more effective PI3K inhibitors.

Regulatory effects of statins on Akt signaling for prevention of cancers

Statins, which are primarily used as lipid-lowering drugs, have been found to exhibit anti-tumor effects through modulating and interfering with various signaling pathways. In observational studies, statin use has been associated with a significant reduction in the progression of various cancers, including colon, lung, prostate, pancreas, and esophagus cancer, as well as melanoma and B and T cell lymphoma. The mevalonate pathway, which is affected by statins, plays a crucial role in activating Rho, Ras, and Rab proteins, thereby impacting the proliferation and apoptosis of tumor cells. Statins block this pathway, leading to the inhibition of isoprenoid units, which are critical for the activation of these key proteins, thereby affecting cancer cell behavior. Additionally, statins affect MAPK and Cdk2, which in turn reduce the expression of p21 and p27 cyclin-dependent kinase inhibitors. Akt signaling plays a crucial role in key cancer cell features like proliferation, invasion, and apoptosis by activating multiple effectors in downstream pathways such as FOXO, PTEN, NF-κB, GSK3β, and mTOR. The PI3K/Akt signaling is necessary for many events in the metastatic pathway and has been implicated in the resistance to cytostatic drugs. The Akt/PTEN axis is currently attracting great interest for its role in carcinogenesis. Statins have been shown to activate the purinergic receptor P2X7 and affect Akt signaling, which may have important anti-cancer effects. Hence, targeting Akt shows promise as an effective approach to cancer prevention and therapy. This review aims to provide a comprehensive discussion on the specific impact of statins through Akt signaling in different types of cancer.

100 years of the Warburg effect: A cancer metabolism endeavor

If you are a scientist and you only know one thing about tumor metabolism, it's likely the Warburg effect. But who was Otto Warburg, and how did his discoveries regarding the metabolism of tumors shape our current thinking about the metabolic needs of cancer cells?

Transcriptomics-based analysis of Macrobrachium rosenbergii growth retardation

Macrobrachium rosenbergii is an economically important crustacean in many parts of the world, but in recent years, growth retardation has become an increasingly serious issue. While the underlying causes remain unclear, this has inevitably impacted on aquaculture and production outputs. In this study, gill, hepatopancreas, and muscle tissue samples from M. rosenbergii, with distinct growth differences, underwent transcriptome sequencing and bioinformatics analyses using high-throughput sequencing. In total, 59,796 unigenes were annotated. Differential expression analyses showed that the most differentially expressed genes (DEGs) were screened in gill tissue (1790 DEGs). In muscle and hepatopancreas tissues, 696 and 598 DEGs were screened, respectively. These DEGs were annotated to Kyoto Encyclopedia of Genes and Genomes pathways, which identified several significantly enriched pathways related to growth metabolism, such as PI3K-AKT, glycolysis/gluconeogenesis, and starch and sucrose metabolism. These results suggest that low growth metabolism levels may be one cause of M. rosenbergii growth retardation. Our data provide support for further investigations into the causes and molecular mechanisms underpinning growth retardation in M. rosenbergii.

Methylome-wide analysis in systemic microbial-induced experimental periodontal disease in mice with different susceptibility

Objective

The study delved into the epigenetic factors associated with periodontal disease in two lineages of mice, namely C57bl/6 and Balb/c. Its primary objective was to elucidate alterations in the methylome of mice with distinct genetic backgrounds following systemic microbial challenge, employing high-throughput DNA methylation analysis as the investigative tool.

Methods

Porphyromonas gingivalis (Pg)was orally administered to induce periodontitis in both Balb/c and C57bl/6 lineage. After euthanasia, genomic DNA from both maxilla and blood were subjected to bisulfite conversion, PCR amplification and genome-wide DNA methylation analysis using the Ovation RRBS Methyl-Seq System coupled with the Illumina Infinium Mouse Methylation BeadChip.

Results

Of particular significance was the distinct methylation profile observed within the Pg-induced group of the Balb/c lineage, contrasting with both the control and Pg-induced groups of the C57bl/6 lineage. Utilizing rigorous filtering criteria, we successfully identified a substantial number of differentially methylated regions (DMRs) across various tissues and comparison groups, shedding light on the prevailing hypermethylation in non-induced cohorts and hypomethylation in induced groups. The comparison between blood and maxilla samples underscored the unique methylation patterns specific to the jaw tissue. Our comprehensive methylome analysis further unveiled statistically significant disparities, particularly within promoter regions, in several comparison groups.

Conclusion

The differential DNA methylation patterns observed between C57bl/6 and Balb/c mouse lines suggest that epigenetic factors contribute to the variations in disease susceptibility. The identified differentially methylated regions associated with immune regulation and inflammatory response provide potential targets for further investigation. These findings emphasize the importance of considering epigenetic mechanisms in the development and progression of periodontitis.

Using protein turnover assay to explore the drug mechanism of Carfilzomib

Carfilzomib (CFZ) is the second-generation proteasome inhibitor that is approved by Food and Drug Administration (FDA) of USA for the treatment of relapsed and refractory multiple myeloma. Although the preclinical and clinical efficacy of CFZ is obvious, the mechanism by which CFZ leads to cell death has not been fully elucidated. Since CFZ primarily functions as a proteasome inhibitor, profiling CFZ-induced changes in protein turnover at the systematic level is sufficient and necessary. In this study, we characterize the effects of CFZ on the stability of 15,000 human proteins using Protein Turnover Assay (ProTA). CFZ affects fundamental cellular glycolysis, nitric oxide production and proteasome subunit homeostasis in multiple myeloma cells. In addition, LY294002 or KU-0063794 has synergistic effects with CFZ in multiple myeloma treatment. A profound understanding of how cells respond to chemotherapeutic agents provides insights into the basic mechanism of drug function and the rationale for CFZ combination therapy.

UBQLN4 promotes the proliferation and invasion of non-small cell lung cancer cell by regulating PI3K/AKT pathway

BACKGROUND

Ubiquilin-4 (UBQLN4), a member of the ubiquilin family, has received limited attention in cancer research to date. Here, we investigated for the first time the functional role and mechanism of UBQLN4 in non-small cell lung cancer (NSCLC).

METHODS

The Cancer Genome Atlas (TCGA) database was employed to validate UBQLN4 as a differentially expressed gene. Expression differences of UBQLN4 in NSCLC cells and tissues were assessed using immunohistochemistry (IHC) experiment and western blotting (WB) experiment. Kaplan-Meier analysis was conducted to examine the association between UBQLN4 expression and NSCLC prognosis. Functional analyses of UBQLN4 were performed through cell counting kit-8 (CCK-8), colony formation, and transwell invasion assays. The impact of UBQLN4 on tumor-associated signaling pathways was assessed using the path scan intracellular signaling array. In vivo tumorigenesis experiments were conducted to further investigate the influence of UBQLN4 on tumor formation.

RESULTS

UBQLN4 exhibited up-regulation in both NSCLC tissues and cells. Additionally, over-expression of UBQLN4 was associated with an unfavorable prognosis in NSCLC patients. Functional loss analyses demonstrated that inhibiting UBQLN4 could suppress the proliferation and invasion of NSCLC cells in both in vitro and in vivo settings. Conversely, functional gain experiments yielded opposite results. Path scan intracellular signaling array results suggested that the role of UBQLN4 is associated with the PI3K/AKT pathway, a correlation substantiated by in vitro and in vivo tumorigenesis experiments.

CONCLUSION

We validated that UBQLN4 promotes proliferation and invasion of NSCLC cells by activating the PI3K/AKT pathway, thereby facilitating the progression of NSCLC. These findings underscore the potential of targeting UBQLN4 as a therapeutic strategy for NSCLC.

Corneal keratocytes, fibroblasts, and myofibroblasts exhibit distinct transcriptional profiles in vitro

Purpose

After stromal injury to the cornea, the release of growth factors and pro-inflammatory cytokines promotes the activation of quiescent keratocytes into a migratory fibroblast and/or fibrotic myofibroblast phenotype. Persistence of the myofibroblast phenotype can lead to corneal fibrosis and scarring, which are leading causes of blindness worldwide. This study aims to establish comprehensive transcriptional profiles for cultured corneal keratocytes, fibroblasts, and myofibroblasts to gain insights into the mechanisms through which these phenotypic changes occur.

Methods

Primary rabbit corneal keratocytes were cultured in either defined serum-free media (SF), fetal bovine serum (FBS) containing media, or in the presence of TGF-β1 to induce keratocyte, fibroblast, or myofibroblast phenotypes, respectively. Bulk RNA sequencing followed by bioinformatic analyses was performed to identify significant differentially expressed genes (DEGs) and enriched biological pathways for each phenotype.

Results

Genes commonly associated with keratocytes, fibroblasts, or myofibroblasts showed high relative expression in SF, FBS, or TGF-β1 culture conditions, respectively. Differential expression and functional analyses revealed novel DEGs for each cell type, as well as enriched pathways indicative of differences in proliferation, apoptosis, extracellular matrix (ECM) synthesis, cell-ECM interactions, cytokine signaling, and cell mechanics.

Conclusions

Overall, these data demonstrate distinct transcriptional differences among cultured corneal keratocytes, fibroblasts, and myofibroblasts. We have identified genes and signaling pathways that may play important roles in keratocyte differentiation, including many related to mechanotransduction and ECM biology. Our findings have revealed novel molecular markers for each cell type, as well as possible targets for modulating cell behavior and promoting physiological corneal wound healing.

Evolving Management of Breast Cancer in the Era of Predictive Biomarkers and Precision Medicine

Breast cancer is the most common cancer among women in the world as well as in the United States. Molecular and histological differentiation have helped clinicians optimize treatments with various therapeutics, including hormonal therapy, chemotherapy, immunotherapy, and radiation therapy. Recently, immunotherapy has become the standard of care in locally advanced triple-negative breast cancer and an option across molecular subtypes for tumors with a high tumor mutation burden. Despite the advancements in personalized medicine directing the management of localized and advanced breast cancers, the emergence of resistance to these therapies is the leading cause of death among breast cancer patients. Therefore, there is a critical need to identify and validate predictive biomarkers to direct treatment selection, identify potential responders, and detect emerging resistance to standard therapies. Areas of active scientific and clinical research include novel personalized and predictive biomarkers incorporating tumor microenvironment, tumor immune profiling, molecular characterization, and histopathological differentiation to predict response and the potential emergence of resistance.

Sevoflurane enhances autophagy via Rac1 to attenuate lung ischaemia‒reperfusion injury

Sevoflurane can attenuate lung ischaemia‒reperfusion injury (LIRI). However, the protective mechanism is unclear. In this study, we developed a LIRI model in vivo that animals (SD, n = 15) were subjected to the administration of 2.2 % sevoflurane 30 min before the onset of left pulmonary artery clamping for 45 min, which was then followed by 60 min of reperfusion treatment. Then, transcriptome sequencing was used to analyse lung tissues. Autophagy inhibition (3-MA) and Rac1-overexpression transfection plasmids were used in BEAS-2B cells, and BEAS-2B cells were subjected to hypoxia reoxygenation (H/R) and sevoflurane treatment. In both animal tissue and cells, inflammatory cytokines and apoptotic and autophagy molecules were measured by quantitative real-time PCR, western blotting and immunostaining. As a result, decreased arterial partial oxygen and damage to the histological structure of lung tissues were observed in LIRI model rats, and these effects were reversed by sevoflurane treatment. Activation of inflammation (elevated IL-1β, IL-6, and TNF-α) and apoptosis (elevated cleaved caspase3/caspase3 and Bax, degraded expression of Bcl2) and inhibition of autophagy (elevated P62, degraded expression of Beclin1 and LC3-II/LC3I) in the model group were ameliorated by sevoflurane. Transcriptome sequencing indicated that the PI3K/Akt pathway regulated by Rac1 plays an important role in LIRI. Furthermore, overexpression of Rac1 in a cell line inhibited the protective effect of sevoflurane in LIRI. Autophagy inhibition (3-MA) also prevented the protective effect of sevoflurane on inflammation and apoptosis. As shown in the present study, sevoflurane enhances autophagy via Rac1/PI3K/AKT signalling to attenuate lung ischaemia‒reperfusion injury.

Butyrate improves recovery from experimental necrotizing enterocolitis by metabolite hesperetin through potential inhibition the PI3K-Akt pathway

Necrotizing enterocolitis (NEC) is one of the most common and serious intestinal illnesses in newborns and seriously affects their long-term prognosis and survival. Butyrate is a short-chain fatty acid that can relieve intestinal inflammation, but its mechanism of action is unclear. Results from an in vivo neonatal rat model has shown that butyrate caused an improved recovery from NEC. These protective effects were associated with the metabolite of hesperetin, as determined by metabolomics and molecular biological analysis. Furthermore, transcriptomics combined with inhibitor assays were used to investigate the mechanism of action of hesperetin in an in vitro NEC model (IEC-6 cells exposed to LPS) to further investigate the mechanism by which butyrate attenuates NEC. The transcriptomics analysis showed that the PI3K-Akt signaling pathway was involved in the anti-NEC effect of hesperitin. Subsequently, the results using an inhibitor of PI3K (LY294002) indicated that the suppression could be explained by the hesperetin-induced expression of tight junction (TJ) proteins by potentially blocking the PI3K-Akt signaling pathway. In summary, the present study demonstrated that butyrate could improve recovery from NEC with a hesperetin metabolite, causing potential inhibition of the phosphorylation of the PI3K-Akt signaling pathway, resulting in the increased expression of TJ proteins. These findings reveal a potential new therapeutic pathway for the treatment of NEC.

Proteomics Analysis of Duck Lung Tissues in Response to Highly Pathogenic Avian Influenza Virus

Domestic ducks (Anas platyrhynchos domesticus) are resistant to most of the highly pathogenic avian influenza virus (HPAIV) infections. In this study, we characterized the lung proteome and phosphoproteome of ducks infected with the HPAI H5N1 virus (A/duck/India/02CA10/2011/Agartala) at 12 h, 48 h, and 5 days post-infection. A total of 2082 proteins were differentially expressed and 320 phosphorylation sites mapping to 199 phosphopeptides, corresponding to 129 proteins were identified. The functional annotation of the proteome data analysis revealed the activation of the RIG-I-like receptor and Jak-STAT signaling pathways, which led to the induction of interferon-stimulated gene (ISG) expression. The pathway analysis of the phosphoproteome datasets also confirmed the activation of RIG-I, Jak-STAT signaling, NF-kappa B signaling, and MAPK signaling pathways in the lung tissues. The induction of ISG proteins (STAT1, STAT3, STAT5B, STAT6, IFIT5, and PKR) established a protective anti-viral immune response in duck lung tissue. Further, the protein-protein interaction network analysis identified proteins like AKT1, STAT3, JAK2, RAC1, STAT1, PTPN11, RPS27A, NFKB1, and MAPK1 as the main hub proteins that might play important roles in disease progression in ducks. Together, the functional annotation of the proteome and phosphoproteome datasets revealed the molecular basis of the disease progression and disease resistance mechanism in ducks infected with the HPAI H5N1 virus.

Multiple isoforms of the Activin-like receptor baboon differentially regulate proliferation and conversion behaviors of neuroblasts and neuroepithelial cells in the Drosophila larval brain

In Drosophila coordinated proliferation of two neural stem cells, neuroblasts (NB) and neuroepithelial (NE) cells, is pivotal for proper larval brain growth that ultimately determines the final size and performance of an adult brain. The larval brain growth displays two phases based on behaviors of NB and NEs: the first one in early larval stages, influenced by nutritional status and the second one in the last larval stage, promoted by ecdysone signaling after critical weight checkpoint. Mutations of the baboon (babo) gene that produces three isoforms (BaboA-C), all acting as type-I receptors of Activin-type transforming growth factor β (TGF-β) signaling, cause a small brain phenotype due to severely reduced proliferation of the neural stem cells. In this study we show that loss of babo function severely affects proliferation of NBs and NEs as well as conversion of NEs from both phases. By analyzing babo-null and newly generated isoform-specific mutants by CRISPR mutagenesis as well as isoform-specific RNAi knockdowns in a cell- and stage-specific manner, our data support differential contributions of the isoforms for these cellular events with BaboA playing the major role. Stage-specific expression of EcR-B1 in the brain is also regulated primarily by BaboA along with function of the other isoforms. Blocking EcR function in both neural stem cells results in a small brain phenotype that is more severe than baboA-knockdown alone. In summary, our study proposes that the Babo-mediated signaling promotes proper behaviors of the neural stem cells in both phases and achieves this by acting upstream of EcR-B1 expression in the second phase.

Small molecule targeted therapies for endometrial cancer: progress, challenges, and opportunities

Endometrial cancer (EC) is a common malignancy among women worldwide, and its recurrence makes it a common cause of cancer-related death. Surgery and external radiation, chemotherapy, or a combination of strategies are the cornerstone of therapy for EC patients. However, adjuvant treatment strategies face certain drawbacks, such as resistance to chemotherapeutic drugs; therefore, it is imperative to explore innovative therapeutic strategies to improve the prognosis of EC. With the development of pathology and pathophysiology, several biological targets associated with EC have been identified, including PI3K/Akt/mTOR, PARP, GSK-3β, STAT-3, and VEGF. In this review, we summarize the progress of small molecule targeted therapies in terms of both basic research and clinical trials and provide cases of small molecules combined with fluorescence properties in the clinical applications of integrated diagnosis and treatment. We hope that this review will facilitate the further understanding of the regulatory mechanism governing the dysregulation of oncogenic signaling in EC and provide insights into the possible future directions of targeted therapeutic regimens for EC treatment by developing new agents with fluorescence properties for the clinical applications of integrated diagnosis and treatment.

HER2/PI3K/AKT pathway in HER2-positive breast cancer: A review

Breast cancer is currently the most commonly occurring cancer globally. Among breast cancer cases, the human epidermal growth factor receptor 2 (HER2)-positive breast cancer accounts for 15% to 20% and is a crucial focus in the treatment of breast cancer. Common HER2-targeted drugs approved for treating early and/or advanced breast cancer include trastuzumab and pertuzumab, which effectively improve patient prognosis. However, despite treatment, most patients with terminal HER2-positive breast cancer ultimately suffer death from the disease due to primary or acquired drug resistance. The prevalence of aberrantly activated the protein kinase B (AKT) signaling in HER2-positive breast cancer was already observed in previous studies. It is well known that p-AKT expression is linked to an unfavorable prognosis, and the phosphatidylinositol-3-kinase (PI3K)/AKT pathway, as the most common mutated pathway in breast cancer, plays a major role in the mechanism of drug resistance. Therefore, in the current review, we summarize the molecular alterations present in HER2-positive breast cancer, elucidate the relationships between HER2 overexpression and alterations in the PI3K/AKT signaling pathway and the pathways of the alterations in breast cancer, and summarize the resistant mechanism of drugs targeting the HER2-AKT pathway, which will provide an adjunctive therapeutic rationale for subsequent resistance to directed therapy in the future.

DAB2IP inhibits glucose uptake by modulating HIF-1α ubiquitination under hypoxia in breast cancer

Metabolic reprogramming has become increasingly important in tumor biology research. The glucose metabolic pathway is a major energy source and is often dysregulated in breast cancer. DAB2IP is widely reported to be a tumor suppressor that acts as a scaffold protein to suppress tumor malignancy in breast cancer. Interestingly, DAB2IP has also been found to be a potential regulator of glucose uptake; however, the exact mechanism remains unclear. In this study, we found that DAB2IP inhibited glucose uptake under hypoxia conditions in breast cancer cells by suppressing HIF-1α signals. Mechanically, DAB2IP interacted with the E3 ubiquitin ligase STUB1 via its PER domain, thus triggering STUB1 mediated HIF-1α ubiquitylation and degradation, and inhibit glucose metabolism and tumor progression. Deleting the PER domain abrogated the DAB2IP-related inhibitory effects on glucose uptake, intracellular ATP production, and lactic acid production in breast cancer cells. These findings elucidate the biological roles of DAB2IP in cancer-related glucose metabolism as well as a novel mechanism by which STUB1-driven HIF-1α ubiquitylated degradation is regulated in breast cancer.

Macrocyclization strategy for improving candidate profiles in medicinal chemistry

Macrocycles are defined as cyclic compounds with 12 or more members. In medicinal chemistry, they are categorized based on their core chemistry into cyclic peptides and macrocycles. Macrocycles are advantageous because of their structural diversity and ability to achieve high affinity and selectivity towards challenging targets that are often not addressable by conventional small molecules. The potential of macrocyclization to optimize drug-like properties while maintaining adequate bioavailability and permeability has been emphasized as a key innovation in medicinal chemistry. This review provides a detailed case study of the application of macrocyclization over the past 5 years, starting from the initial analysis of acyclic active compounds to optimization of the resulting macrocycles for improved efficacy and drug-like properties. Additionally, it illustrates the strategic value of macrocyclization in contemporary drug discovery efforts.

YY1 mediated DCUN1D5 transcriptional activation promotes triple-negative breast cancer progression by targeting FN1/PI3K/AKT pathway

Triple-negative breast cancer (TNBC) is more aggressive and has a higher metastasis rate compared with other subtypes of breast cancer. Due to the lack of drug-targetable receptors, chemotherapy is now the only available systemic treatment for TNBC. However, some patients might still develop drug resistance and have poor prognosis. Therefore, novel molecular biomarkers and new treatment targets are urgently needed for patients with TNBC. To provide molecular insights into TNBC progression, we investigated the function and the underlying mechanism of Defective in cullin neddylation 1 domain containing 5 (DCUN1D5) in the regulation of TNBC. By TCGA dataset and surgical specimens with immunohistochemical (IHC) staining method, DCUN1D5 was identified to be significantly upregulated in TNBC tumor tissues and negatively associated with prognosis. A series of in vitro and in vivo experiments were performed to confirm the oncogenic role of DCUN1D5 in TNBC. Overexpression of FN1 or PI3K/AKT activator IGF-1 could restore the proliferative and invasive ability induced by DCUN1D5 knockdown and DCUN1D5 could act as a novel transcriptional target of transcription factor Yin Yang 1 (YY1). In conclusion, YY1-enhanced DCUN1D5 expression could promote TNBC progression by FN1/PI3K/AKT pathway and DCUN1D5 might be a potential prognostic biomarker and therapeutic target for TNBC treatment.

Role of histone methyltransferase KMT2D in BMSC osteogenesis via AKT signaling

Understanding the precise mechanism of BMSC (bone marrow mesenchymal stem cell) osteogenesis is critical for metabolic bone diseases and bone reconstruction. The histone-lysine N-methyltransferase 2D (KMT2D) acts as an important methyltransferase related with congenital skeletal disorders, yet the function of KMT2D in osteogenesis was unclear. Here we found that KMT2D expression was decreased in BMSCs collected from ovariectomized mice. Moreover, during human BMSC differentiation under mineralization induction, the mRNA level of KMT2D was gradually elevated. After KMT2D knockdown, the in vitro osteogenic differentiation of BMSCs was inhibited, while the in vivo bone formation potential of BMSCs was attenuated. Further, in BMSCs, KMT2D knockdown reduced the level of phosphorylated protein kinase B (p-AKT). SC-79, a common activator of AKT signaling, reversed the suppressing influence of KMT2D knockdown on BMSCs differentiation towards osteoblast. These results indicate that the KMT2D-AKT pathway plays an essential role in the osteogenesis process of human BMSCs (hBMSCs), which might provide new avenues for the molecular medicine of bone diseases and regeneration.

Phosphorylation of FOXK2 at Thr13 and Ser30 by PDK2 sustains glycolysis through a positive feedback manner in ovarian cancer

Ovarian cancer is one of the most common gynecological malignant tumors with insidious onset, strong invasiveness, and poor prognosis. Metabolic alteration, particularly aerobic glycolysis, which is tightly regulated by transcription factors, is associated with the malignant behavior of OC. We screened FOXK2 in this study as a key transcription factor that regulates glycolysis in OC. FOXK2 is overly expressed in OC, and poor prognosis is predicted by overexpression. FOXK2 promotes OC cell proliferation both in vitro and in vivo and cell migration in vitro. Further studies showed that PDK2 directly binds to the forkhead-associated (FHA) domain of FOXK2 to phosphorylate FOXK2 at Thr13 and Ser30, thereby enhancing the transcriptional activity of FOXK2. FOXK2 transcriptionally regulates the expression of PDK2, thus forming positive feedback to sustain glycolysis in OC cells.

A bird's-eye overview of molecular mechanisms regulating feed intake in chickens-with mammalian comparisons

In recent decades, a lot of research has been conducted to explore poultry feeding behavior. However, up to now, the processes behind poultry feeding behavior remain poorly understood. The review generalizes modern expertise about the hormonal regulation of feeding behavior in chickens, focusing on signaling pathways mediated by insulin, leptin, and ghrelin and regulatory pathways with a cross-reference to mammals. This overview also summarizes state-of-the-art research devoted to hypothalamic neuropeptides that control feed intake and are prime candidates for predictors of feeding efficiency. Comparative analysis of the signaling pathways that mediate the feed intake regulation allowed us to conclude that there are major differences in the processes by which hormones influence specific neuropeptides and their contrasting roles in feed intake control between two vertebrate clades.

Epoxyeicosatrienoic Acids Attenuate LPS-Induced NIH/3T3 Cell Fibrosis through the A2AR and PI3K/Akt Signaling Pathways

Inflammation plays a crucial role in progression of fibrosis. Epoxyeicosatrienoic acids (EET) have multiple protective effects in different diseases, but their ability to inhibit the development of LPS-induced fibrosis remains unknown. The potential therapeutic effects of 11,12-EET were studied in in vitro model of LPS-induced fibrosis. Mouse embryonic fibroblast cells NIH/3T3 were pre-incubated with 1 μM 11,12-EET and/or a structural analogue and selective EET antagonist 14,15-epoxyeicosa-5(Z)-enoic acid before exposing to LPS. The effect of EET was evaluated by the protein and mRNA expression of NF-κB, collagens I and III, and α-smooth muscle actin by Western blotting and quantitative reverse transcription PCR, respectively. LPS provoked inflammation and fibrosis-like changes accompanied by elevated expression of NF-κB and collagens in NIH/3T3 cells. We also studied the effects of 11,12-EET on the A2AR and PI3K/Akt signaling pathways in intact and LPS-treated NIH/3T3 cells. 11,12-EET prevented inflammation and fibrosis-like changes through up-regulation of A2AR and PI3K/Akt signaling pathways. Our findings demonstrate the potential antifibrotic effects of 11,12-EET, which can be natural antagonists of tissue fibrosis.

Segmental Odontomaxillary Dysplasia: A Case Report and Review of the Literature

Segmental odontomaxillary dysplasia (SOD) is a rare and unusual nonhereditary developmental disorder that affects one side of the maxilla, impacting the hard tissue, soft tissue, and dentition in the affected area. It most frequently presents with enlargement of the gingival and osseous tissue of the affected side and hypodontia of the involved quadrant. Cutaneous irregularities of the impacted area are also common. We report a case of SOD arising in the right maxilla of a three-year-old female. Our report and review of the literature highlight the clinical, radiographic, and histopathologic characteristics of SOD, as well as the management of patients and the proposed etiologies of its pathogenesis.

Effects of chemical in vitro activation versus fragmentation on human ovarian tissue and follicle growth in culture

STUDY QUESTION

What is the effect of the chemical in vitro activation (cIVA) protocol compared with fragmentation only (Frag, also known as mechanical IVA) on gene expression, follicle activation and growth in human ovarian tissue in vitro?

SUMMARY ANSWER

Although histological assessment shows that cIVA significantly increases follicle survival and growth compared to Frag, both protocols stimulate extensive and nearly identical transcriptomic changes in cultured tissue compared to freshly collected ovarian tissue, including marked changes in energy metabolism and inflammatory responses.

WHAT IS KNOWN ALREADY

Treatments based on cIVA of the phosphatase and tensin homolog (PTEN)-phosphatidylinositol 3-kinase (PI3K) pathway in ovarian tissue followed by auto-transplantation have been administered to patients with refractory premature ovarian insufficiency (POI) and resulted in live births. However, comparable effects with mere tissue fragmentation have been shown, questioning the added value of chemical stimulation that could potentially activate oncogenic responses.

STUDY DESIGN SIZE DURATION

Fifty-nine ovarian cortical biopsies were obtained from consenting women undergoing elective caesarean section (C-section). The samples were fragmented for culture studies. Half of the fragments were exposed to bpV (HOpic)+740Y-P (Frag+cIVA group) during the first 24 h of culture, while the other half were cultured with medium only (Frag group). Subsequently, both groups were cultured with medium only for an additional 6 days. Tissue and media samples were collected for histological, transcriptomic, steroid hormone, and cytokine/chemokine analyses at various time points.

PARTICIPANTS/MATERIALS SETTING METHODS

Effects on follicles were evaluated by counting and scoring serial sections stained with hematoxylin and eosin before and after the 7-day culture. Follicle function was assessed by quantification of steroids by ultra-performance liquid chromatography tandem-mass spectrometry at different time points. Cytokines and chemokines were measured by multiplex assay. Transcriptomic effects were measured by RNA-sequencing (RNA-seq) of the tissue after the initial 24-h culture. Selected differentially expressed genes (DEGs) were validated by quantitative PCR and immunofluorescence in cultured ovarian tissue as well as in KGN cell (human ovarian granulosa-like tumor cell line) culture experiments.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to the Frag group, the Frag+cIVA group exhibited a significantly higher follicle survival rate, increased numbers of secondary follicles, and larger follicle sizes. Additionally, the tissue in the Frag+cIVA group produced less dehydroepiandrosterone compared to Frag. Cytokine measurement showed a strong inflammatory response at the start of the culture in both groups. The RNA-seq data revealed modest differences between the Frag+cIVA and Frag groups, with only 164 DEGs identified using a relaxed cut-off of false discovery rate (FDR) <0.1. Apart from the expected PI3K-protein kinase B (Akt) pathway, cIVA also regulated pathways related to hypoxia, cytokines, and inflammation. In comparison to freshly collected ovarian tissue, gene expression in general was markedly affected in both the Frag+cIVA and Frag groups, with a total of 3119 and 2900 DEGs identified (FDR < 0.001), respectively. The top enriched gene sets in both groups included several pathways known to modulate follicle growth such as mammalian target of rapamycin (mTOR)C1 signaling. Significant changes compared to fresh tissue were also observed in the expression of genes encoding for steroidogenesis enzymes and classical granulosa cell markers in both groups. Intriguingly, we discovered a profound upregulation of genes related to glycolysis and its upstream regulator in both Frag and Frag+cIVA groups, and these changes were further boosted by the cIVA treatment. Cell culture experiments confirmed glycolysis-related genes as direct targets of the cIVA drugs. In conclusion, cIVA enhances follicle growth, as expected, but the mechanisms may be more complex than PI3K-Akt-mTOR alone, and the impact on function and quality of the follicles after the culture period remains an open question.

LARGE SCALE DATA

Data were deposited in the GEO data base, accession number GSE234765. The code for sequencing analysis can be found in https://github.com/tialiv/IVA_project.

LIMITATIONS REASONS FOR CAUTION

Similar to the published IVA protocols, the first steps in our study were performed in an in vitro culture model where the ovarian tissue was isolated from the regulation of hypothalamic-pituitary-ovarian axis. Further in vivo experiments will be needed, for example in xeno-transplantation models, to explore the long-term impacts of the discovered effects. The tissue collected from patients undergoing C-section may not be comparable to tissue of patients with POI.

WIDER IMPLICATIONS OF THE FINDINGS

The general impact of fragmentation and short (24 h) in vitro culture on gene expression in ovarian tissue far exceeded the effects of cIVA. Yet, follicle growth was stimulated by cIVA, which may suggest effects on specific cell populations that may be diluted in bulk RNA-seq. Nevertheless, we confirmed the impact of cIVA on glycolysis using a cell culture model, suggesting impacts on cellular signaling beyond the PI3K pathway. The profound changes in inflammation and glycolysis following fragmentation and culture could contribute to follicle activation and loss in ovarian tissue culture, as well as in clinical applications, such as fertility preservation by ovarian tissue auto-transplantation.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by research grants from European Union's Horizon 2020 Research and Innovation Programme (Project ERIN No. 952516, FREIA No. 825100), Swedish Research Council VR (2020-02132), StratRegen funding from Karolinska Institutet, KI-China Scholarship Council (CSC) Programme and the Natural Science Foundation of Hunan (2022JJ40782). International Iberian Nanotechnology Laboratory Research was funded by the European Union's H2020 Project Sinfonia (857253) and SbDToolBox (NORTE-01-0145-FEDER-000047), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund. No competing interests are declared.

Tumor biomarkers for diagnosis, prognosis and targeted therapy

Tumor biomarkers, the substances which are produced by tumors or the body's responses to tumors during tumorigenesis and progression, have been demonstrated to possess critical and encouraging value in screening and early diagnosis, prognosis prediction, recurrence detection, and therapeutic efficacy monitoring of cancers. Over the past decades, continuous progress has been made in exploring and discovering novel, sensitive, specific, and accurate tumor biomarkers, which has significantly promoted personalized medicine and improved the outcomes of cancer patients, especially advances in molecular biology technologies developed for the detection of tumor biomarkers. Herein, we summarize the discovery and development of tumor biomarkers, including the history of tumor biomarkers, the conventional and innovative technologies used for biomarker discovery and detection, the classification of tumor biomarkers based on tissue origins, and the application of tumor biomarkers in clinical cancer management. In particular, we highlight the recent advancements in biomarker-based anticancer-targeted therapies which are emerging as breakthroughs and promising cancer therapeutic strategies. We also discuss limitations and challenges that need to be addressed and provide insights and perspectives to turn challenges into opportunities in this field. Collectively, the discovery and application of multiple tumor biomarkers emphasized in this review may provide guidance on improved precision medicine, broaden horizons in future research directions, and expedite the clinical classification of cancer patients according to their molecular biomarkers rather than organs of origin.