Disrupting Insulin and IGF Receptor Function in Cancer

Role of Insulin-like Growth Factor-1 Receptor in Tobacco Smoking-Associated Lung Cancer Development

Cancer remains a significant global health concern, with lung cancer consistently leading as one of the most common malignancies. Genetic aberrations involving receptor tyrosine kinases (RTKs) are known to be associated with cancer initiation and development, but RTK involvement in smoking-associated lung cancer cases is not well understood. The Insulin-like Growth Factor 1 Receptor (IGF-1R) is a receptor that plays a critical role in lung cancer development. Its signaling pathway affects the growth and survival of cancer cells, and high expression is linked to poor prognosis and resistance to treatment. Several reports have shown that by activating IGF-1R, tobacco smoke-related carcinogens promote lung cancer and chemotherapy resistance. However, the relationship between IGF-1R and cancer is complex and can vary depending on the type of cancer. Ongoing investigations are focused on developing therapeutic strategies to target IGF-1R and overcome chemotherapy resistance. Overall, this review explores the intricate connections between tobacco smoke-specific carcinogens and the IGF-1R pathway in lung carcinogenesis. This review further highlights the challenges in using IGF-1R inhibitors as targeted therapy for lung cancer due to structural similarities with insulin receptors. Overcoming these obstacles may require a comprehensive approach combining IGF-1R inhibition with other selective agents for successful cancer treatment.

Insulin Resistance: The Increased Risk of Cancers

Insulin resistance, also known as impaired insulin sensitivity, is the result of a decreased reaction of insulin signaling to blood glucose levels. This state is observed when muscle cells, adipose tissue, and liver cells, improperly respond to a particular concentration of insulin. Insulin resistance and related increased plasma insulin levels (hyperinsulinemia) may cause metabolic impairments, which are pathological states observed in obesity and type 2 diabetes mellitus. Observations of cancer patients confirm that hyperinsulinemia is a major factor influencing obesity, type 2 diabetes, and cancer. Obesity and diabetes have been reported as risks of the initiation, progression, and metastasis of several cancers. However, both of the aforementioned pathologies may independently and additionally increase the cancer risk. The state of metabolic disorders observed in cancer patients is associated with poor outcomes of cancer treatment. For example, patients suffering from metabolic disorders have higher cancer recurrence rates and their overall survival is reduced. In these associations between insulin resistance and cancer risk, an overview of the various pathogenic mechanisms that play a role in the development of cancer is discussed.

Investigating the clinical role and prognostic value of genes related to insulin-like growth factor signaling pathway in thyroid cancer

BACKGROUND

Thyroid cancer (THCA) is the most common endocrine malignancy having a female predominance. The insulin-like growth factor (IGF) pathway contributed to the unregulated cell proliferation in multiple malignancies. We aimed to explore the IGF-related signature for THCA prognosis.

METHOD

The TCGA-THCA dataset was collected from the Cancer Genome Atlas (TCGA) for screening of key prognostic genes. The limma R package was applied for differentially expressed genes (DEGs) and the clusterProfiler R package was used for the Gene Ontology (GO) and KEGG analysis of DEGs. Then, the un/multivariate and least absolute shrinkage and selection operator (Lasso) Cox regression analysis was used for the establishment of RiskScore model. Receiver Operating Characteristic (ROC) analysis was used to verify the model's predictive performance. CIBERSORT and MCP-counter algorithms were applied for immune infiltration analysis. Finally, we analyzed the mutation features and the correlation between the RiskScore and cancer hallmark pathway by using the GSEA.

RESULT

We obtained 5 key RiskScore model genes for patient's risk stratification from the 721 DEGs. ROC analysis indicated that our model is an ideal classifier, the high-risk patients are associated with the poor prognosis, immune infiltration, high tumor mutation burden (TMB), stronger cancer stemness and stronger correlation with the typical cancer-activation pathways. A nomogram combined with multiple clinical features was developed and exhibited excellent performance upon long-term survival quantitative prediction.

CONCLUSIONS

We constructed an excellent prognostic model RiskScore based on IGF-related signature and concluded that the IGF signal pathway may become a reliable prognostic phenotype in THCA intervention.

Ketosis Suppression and Ageing (KetoSAge): The Effects of Suppressing Ketosis in Long Term Keto-Adapted Non-Athletic Females

Most studies on ketosis have focused on short-term effects, male athletes, or weight loss. Hereby, we studied the effects of short-term ketosis suppression in healthy women on long-standing ketosis. Ten lean (BMI 20.5 ± 1.4), metabolically healthy, pre-menopausal women (age 32.3 ± 8.9) maintaining nutritional ketosis (NK) for > 1 year (3.9 years ± 2.3) underwent three 21-day phases: nutritional ketosis (NK; P1), suppressed ketosis (SuK; P2), and returned to NK (P3). Adherence to each phase was confirmed with daily capillary D-beta-hydroxybutyrate (BHB) tests (P1 = 1.9 ± 0.7; P2 = 0.1 ± 0.1; and P3 = 1.9 ± 0.6 pmol/L). Ageing biomarkers and anthropometrics were evaluated at the end of each phase. Ketosis suppression significantly increased: insulin, 1.78-fold from 33.60 (± 8.63) to 59.80 (± 14.69) pmol/L (p = 0.0002); IGF1, 1.83-fold from 149.30 (± 32.96) to 273.40 (± 85.66) µg/L (p = 0.0045); glucose, 1.17-fold from 78.6 (± 9.5) to 92.2 (± 10.6) mg/dL (p = 0.0088); respiratory quotient (RQ), 1.09-fold 0.66 (± 0.05) to 0.72 (± 0.06; p = 0.0427); and PAI-1, 13.34 (± 6.85) to 16.69 (± 6.26) ng/mL (p = 0.0428). VEGF, EGF, and monocyte chemotactic protein also significantly increased, indicating a pro-inflammatory shift. Sustained ketosis showed no adverse health effects, and may mitigate hyperinsulinemia without impairing metabolic flexibility in metabolically healthy women.

Ketogenic diet and metastasis: A critical review of the literature and possible mechanisms

The ketogenic diet (KD) is a low-carb diet that has been indicated as a possible coadjuvant in cancer therapy, mainly due to its capacity to reduce glycolysis production, inflammation, and oxidative stress. However, KD's role in metastasis remains poorly explored. This study aims to provide a critical review of the literature about KD's efficacy in metastasis therapy and the possible molecular mechanisms behind it. Initially, general concepts on KD and metastasis are discussed. Then, it delves deeper into the main cancer mechanisms explored by KD experimental studies, discussing the central results obtained in metastasis research and their main limiting conditions. Following, there is a critical analysis of clinical trials, including those in the grey literature. In the end, there is a summary of the actual studies' limitations and barriers to future research. To date, it is possible to conclude that there is not enough evidence supporting the efficacy of KD in the treatment of metastasis.

Insulin Stimulates IL-23 Expression in Human Adipocytes: A Possible Explanation for the Higher Prevalence of Psoriasis in Obesity

Purpose

Psoriasis is a chronic systemic inflammatory disease involving the production of many pro-inflammatory cytokines derived from immune cells and interacting with different tissues leading to the typical skin lesions. Psoriasis shows a higher prevalence and a worse progression in obese than in lean subjects. The IL-23/IL-17 immune axis has a pivotal role in the pathogenesis of psoriasis and anti-IL-23 monoclonal antibodies are highly effective in its treatment. Since obesity in frequently associated with elevated insulin plasma levels, we have investigated the ability of in vitro differentiated human adipocytes to produce IL-23 at basal conditions and after insulin stimulation.

Material and Methods

In vitro differentiated human adipocytes were incubated in the absence and presence of different insulin concentrations and the expression of IL-23 was analyzed by real-time PCR and Western blotting.

Results

The results of this study show that in vitro differentiated human adipocytes spontaneously express IL-23 mRNA and protein being stimulated by insulin in a dose-dependent manner. The stimulatory effects of insulin on IL-23 expression were specific since it did not stimulate the expression of other well-known cytokines involved in psoriasis pathogenesis such as Il-22 nor LL-37. Furthermore, lipopolysaccharide did not stimulate IL-23 expression in human adipocytes, thus highlightening the specific effects of insulin in the stimulation of IL-23 expression in human adipocytes.

Conclusion

Here we show that human adipocytes spontaneously express IL-23 and that insulin stimulates IL-23 production by these cells in a specific manner as other stimuli, known to be involved in psoriasis pathophysiology, are ineffective. These observations could explain the association between psoriasis and obesity, a condition frequently characterized by a state of insulin hypersecretion.

IGF-1 Stimulates Glycolytic ATP Production in MCF-7L Cells

The Insulin-like Growth Factor (IGF) system in breast cancer progression has been a matter of interest for decades, but targeting this system did not result in a successful clinical strategy. The system's complexity and homology of its two receptors-insulin receptor (IR) and type 1 insulin-like growth factor receptor (IGF-1R)-are possible causes. The IGF system maintains cell proliferation and also regulates metabolism, making it a pathway to explore. To understand the metabolic phenotype of breast cancer cells, we quantified their real-time ATP production rate upon acute stimulation with ligands-insulin-like growth factor 1 (1GF-1) and insulin. MCF-7L cells express both IGF-1R and IR, while tamoxifen-resistant MCF-7L (MCF-7L TamR) cells have downregulated IGF-1R with unchanged IR levels. Treating MCF-7L cells with 5 nM IGF-1 increased the glycolytic ATP production rate, while 10 nM insulin did not affect metabolism when compared with the control. Neither treatment altered ATP production in MCF-7L TamR cells. This study provides evidence of the relationship between metabolic dysfunction, cancer, and the IGF axis. In these cells, IGF-1R, and not IR, regulates ATP production.

XENERA-1: a randomised double-blind Phase II trial of xentuzumab in combination with everolimus and exemestane versus everolimus and exemestane in patients with hormone receptor-positive/HER2-negative metastatic breast cancer and non-visceral disease

BACKGROUND

Xentuzumab is a humanised monoclonal antibody that binds to IGF-1 and IGF-2, neutralising their proliferative activity and restoring inhibition of AKT by everolimus. This study evaluated the addition of xentuzumab to everolimus and exemestane in patients with advanced breast cancer with non-visceral disease.

METHODS

This double-blind, randomised, Phase II study was undertaken in female patients with hormone-receptor (HR)-positive/human epidermal growth factor 2 (HER2)-negative advanced breast cancer with non-visceral disease who had received prior endocrine therapy with or without CDK4/6 inhibitors. Patients received a weekly intravenous infusion of xentuzumab (1000 mg) or placebo in combination with everolimus (10 mg/day orally) and exemestane (25 mg/day orally). The primary endpoint was progression-free survival (PFS) per independent review.

RESULTS

A total of 103 patients were randomised and 101 were treated (n = 50 in the xentuzumab arm and n = 51 in the placebo arm). The trial was unblinded early due to high rates of discordance between independent and investigator assessment of PFS. Per independent assessment, median PFS was 12.7 (95% CI 6.8-29.3) months with xentuzumab and 11.0 (7.7-19.5) months with placebo (hazard ratio 1.19; 95% CI 0.55-2.59; p = 0.6534). Per investigator assessment, median PFS was 7.4 (6.8-9.7) months with xentuzumab and 9.2 (5.6-14.4) months with placebo (hazard ratio 1.23; 95% CI 0.69-2.20; p = 0.4800). Tolerability was similar between the arms, with diarrhoea (33.3-56.0%), fatigue (33.3-44.0%) and headache (21.6-40.0%) being the most common treatment-emergent adverse events. The incidence of grade ≥ 3 hyperglycaemia was similar between the xentuzumab (2.0%) and placebo (5.9%) arms.

CONCLUSIONS

While this study demonstrated that xentuzumab could be safely combined with everolimus and exemestane in patients with HR-positive/HER2-negative advanced breast cancer with non-visceral disease, there was no PFS benefit with the addition of xentuzumab. Trial registration ClinicalTrials.gov, NCT03659136. Prospectively registered, September 6, 2018.

Obesity and endocrine-related cancer: The important role of IGF-1

Obesity is increasingly becoming a global epidemic of concern and is considered a risk factor for several endocrine-related cancers. Moreover, obesity is associated with cancer development and poor prognosis. As a metabolic abnormality, obesity leads to a series of changes in insulin, IGF-1, sex hormones, IGFBPs, and adipokines. Among these factors, IGF-1 plays an important role in obesity-related endocrine cancers. This review describes the role of obesity in endocrine-related cancers, such as prostate cancer, breast cancer and pancreatic cancer, focusing on the mechanism of IGF-1 and the crosstalk with estrogen and adipokines. In addition, this review briefly introduces the current status of IGF-1R inhibitors in clinical practice and shows the prospect of IGF-1R inhibitors in combination with other anticancer drugs.

Potential Therapies Targeting the Metabolic Reprogramming of Diabetes-Associated Breast Cancer

In recent years, diabetes-associated breast cancer has become a significant clinical challenge. Diabetes is not only a risk factor for breast cancer but also worsens its prognosis. Patients with diabetes usually show hyperglycemia and hyperinsulinemia, which are accompanied by different glucose, protein, and lipid metabolism disorders. Metabolic abnormalities observed in diabetes can induce the occurrence and development of breast cancer. The changes in substrate availability and hormone environment not only create a favorable metabolic environment for tumorigenesis but also induce metabolic reprogramming events required for breast cancer cell transformation. Metabolic reprogramming is the basis for the development, swift proliferation, and survival of cancer cells. Metabolism must also be reprogrammed to support the energy requirements of the biosynthetic processes in cancer cells. In addition, metabolic reprogramming is essential to enable cancer cells to overcome apoptosis signals and promote invasion and metastasis. This review aims to describe the major metabolic changes in diabetes and outline how cancer cells can use cellular metabolic changes to drive abnormal growth and proliferation. We will specifically examine the mechanism of metabolic reprogramming by which diabetes may promote the development of breast cancer, focusing on the role of glucose metabolism, amino acid metabolism, and lipid metabolism in this process and potential therapeutic targets. Although diabetes-associated breast cancer has always been a common health problem, research focused on finding treatments suitable for the specific needs of patients with concurrent conditions is still limited. Most studies are still currently in the pre-clinical stage and mainly focus on reprogramming the glucose metabolism. More research targeting the amino acid and lipid metabolism is needed.

Suppression of Insulin Receptor Substrate 1 Inhibits Breast Cancer Growth In Vitro and in Female Athymic Mice

Targeting the type I insulin-like growth factor receptor (IGF-IR) has not been successful in breast cancer. Data suggest the highly homologous insulin receptor (IR) may be an alternate growth stimulatory pathway used by cancer cells. Since both receptors phosphorylate the insulin receptor substrate 1 (IRS-1) protein as an immediate consequence of ligand binding, disruption of both receptors could be accomplished by suppression of IRS-1. IRS-1 gene deletion by CRISPR/Cas9 editing resulted in suppression of IGF-I, insulin, and estrogen-stimulated growth in hormone-dependent MCF-7L breast cancer cells. A doxycycline-inducible IRS-1 shRNA lentiviral construct was also used to infect MCF-7L breast cancer cells. IRS-1 shRNA downregulation resulted in decreased responses to IGF-I, insulin, and estradiol in monolayer and anchorage-independent growth assays. Decreased IRS-1 levels also suppressed estradiol-stimulated gene expression and estrogen receptor binding to DNA. Xenograft growth was also inhibited by induction of IRS-1 shRNA. These data show that IRS-1 is a critical regulator of endocrine responsive breast cancer. Efforts to target this adaptor protein could have broader growth inhibitory effects and receptor targeting.

N-Linked Glycosylation in Chinese Hamster Ovary Cells Is Critical for Insulin-like Growth Factor 1 Signaling

Cell surface proteins carrying N-glycans play important roles in inter- and intracellular processes including cell adhesion, development, and cellular recognition. Dysregulation of the glycosylation machinery has been implicated in various diseases, and investigation of global differential cell surface proteome effects due to the loss of N-glycosylation will provide comprehensive insights into their pathogenesis. Cell surface proteins isolated from Parent Pro^-5 CHO cells (W5 cells), two CHO mutants with loss of N-glycosylation function derived from Pro^-5 CHO (Lec1 and Lec4 cells), were subjected to proteome analysis via high-resolution LCMS. We identified 44 and 43 differentially expressed membrane proteins in Lec1 and Lec4 cells, respectively, as compared to W5 cells. The defective N-glycosylation mutants showed increased abundance of integrin subunits in Lec1 and Lec4 cells at the cell surface. We also found significantly reduced levels of IGF-1R (Insulin like growth factor-1 receptor); a receptor tyrosine kinase; and the GTPase activating protein IQGAP1 (IQ motif-containing GTPase activating protein), a highly conserved cytoplasmic scaffold protein) in Lec1 and Lec4 cells. In silico docking studies showed that the IQ domain of IQGAP1 interacts with the kinase domain of IGF-1R. The integrin signaling and insulin growth factor receptor signaling were also enriched according to GSEA analysis and pathway analysis of differentially expressed proteins. Significant reductions of phosphorylation of ERK1 and ERK2 in Lec1 and Lec4 cells were observed upon IGF-1R ligand (IGF-1 LR3) stimulation. IGF-1 LR3, known as Long arginine3-IGF-1, is a synthetic protein and lengthened analog of insulin-like growth factor 1. The work suggests a novel mechanism for the activation of IGF-1 dependent ERK signaling in CHO cells, wherein IQGAP1 plausibly functions as an IGF-1R-associated scaffold protein. Appropriate glycosylation by the enzymes MGAT1 and MGAT5 is thus essential for processing of cell surface receptor IGF-1R, a potential binding partner in IQGAP1 and ERK signaling, the integral components of the IGF pathway.

Current Status and Prospects of Targeted Therapy for Osteosarcoma

Osteosarcoma (OS) is a highly malignant tumor occurring in bone tissue with a high propensity to metastasize, and its underlying mechanisms remain largely elusive. The OS prognosis is poor, and improving the survival of OS patients remains a challenge. Current treatment methods such as surgical approaches, chemotherapeutic drugs, and immunotherapeutic drugs remain ineffective. As research progresses, targeted therapy is gradually becoming irreplaceable. In this review, several treatment modalities for osteosarcoma, such as surgery, chemotherapy, and immunotherapy, are briefly described, followed by a discussion of targeted therapy, the important targets, and new technologies for osteosarcoma treatment.

The Role of Insulin Receptor Substrate Proteins in Bronchopulmonary Dysplasia and Asthma: New Potential Perspectives

Insulin receptor substrates (IRSs) are proteins that are involved in signaling through the insulin receptor (IR) and insulin-like growth factor (IGFR). They can also interact with other receptors including growth factor receptors. Thus, they represent a critical node for the transduction and regulation of multiple signaling pathways in response to extracellular stimuli. In addition, IRSs play a central role in processes such as inflammation, growth, metabolism, and proliferation. Previous studies have highlighted the role of IRS proteins in lung diseases, in particular asthma. Further, the members of the IRS family are the common proteins of the insulin growth factor signaling cascade involved in lung development and disrupted in bronchopulmonary dysplasia (BPD). However, there is no study focusing on the relationship between IRS proteins and BPD yet. Unfortunately, there is still a significant gap in knowledge in this field. Thus, in this review, we aimed to summarize the current knowledge with the major goal of exploring the possible roles of IRS in BPD and asthma to foster new perspectives for further investigations.

HULC targets the IGF1R-PI3K-AKT axis in trans to promote breast cancer metastasis and cisplatin resistance

Insulin-like growth factor I receptor (IGF1R) is frequently upregulated in breast cancer. Due to its intrinsic tyrosine kinase activity, aberrant activation of the IGF1R signaling axis may enhance tumor cell proliferation and cancer stemness, causing tumor relapse, metastasis and resistance to chemotherapy. We utilized a chromatin RNA in situ reverse transcription (CRIST) approach to characterize molecular factors that regulate the IGF1R network. We identified lncRNA HULC (Highly Upregulated in Liver Cancer) as a key trans-regulator of IGF1R in breast cancer cells. Loss of HULC suppressed the expression of IGF1R and the activation of its downstream PI3K/AKT pathway, while HULC overexpression activated the axis in breast cancer cells. Using a transcription-associated trap (RAT) assay, we demonstrated that HULC functioned as a nuclear lncRNA and epigenetically activated IGF1R by directly binding to the intragenic regulatory elements of the gene, orchestrating intrachromosomal interactions, and promoting histone H3K9 acetylation. The activated HULC-IGF1R/PI3K/AKT pathway mediated tumor resistance to cisplatin through the increased expression of cancer stemness markers, including NANOG, SOX2, OCT4, CD44 and ALDH1A1. In immunodeficient mice, stimulation of the HULC-IGF1R pathway promoted tumor metastasis. These data suggest that HULC may be a new epigenetic target for IGF1R axis-targeted therapeutic intervention.

Cryo-EM studies of the apo states of human IGF1R

IGF1R plays an important role in regulating cellular metabolism and growth. As a single transmembrane protein, its structure is flexible. Although previous studies revealed some structures of IGF1R, the cryo-EM apo structures of the receptor have never been reported. Herein, we reported four distinct cryo-EM structures that reveal the apo states of IGF1R. These conformations were classified as "Resting states" and "Active states", according to the orientation of α-CT helices and structural symmetry. In addition, a "Ligand-pocket" was formed in the active conformations, which presented a new view of conformational changes of apo-IGF1R. These results suggest a new dynamic change model to show the details of why and how ligands can bind to IGF1R.

Insulin and cancer: a tangled web

For a century, since the pioneering work of Otto Warburg, the interwoven relationship between metabolism and cancer has been appreciated. More recently, with obesity rates rising in the U.S. and worldwide, epidemiologic evidence has supported a link between obesity and cancer. A substantial body of work seeks to mechanistically unpack the association between obesity, altered metabolism, and cancer. Without question, these relationships are multifactorial and cannot be distilled to a single obesity- and metabolism-altering hormone, substrate, or factor. However, it is important to understand the hormone-specific associations between metabolism and cancer. Here, we review the links between obesity, metabolic dysregulation, insulin, and cancer, with an emphasis on current investigational metabolic adjuncts to standard-of-care cancer treatment.

Cryo-EM structure reveals polymorphic ligand-bound states of IGF1R

Type 1 insulin-like growth factor receptor (IGF1R) plays an important role in regulating cellular metabolism and cell growth and has been identified as an anticancer drug target. Although previous studies have revealed some structures of IGF1R with different ligands, the continuous dynamic conformation change remains unclear. Here, we report 10 distinct structures (7.9-3.6 Å) of IGF1R bound to IGF1 or insulin to reveal the polymorphic conformations of ligand-bound IGF1R. These results showed that the α-CT², disulfide bond (C670-C670'), and FnIII-2 domains had the most flexible orientations for the conformational change that occurs when ligands bind to the receptor. In addition, we found one special conformation (tentatively named the diverter-switch state) in both complexes, which may be one of the apo-IGF1R forms under ligand-treatment conditions. Hence, these results illustrated the mechanism of how different ligands could bind to human IGF1R and provided a rational template for drug design.

Dietary Inhibitors of CYP3A4 Are Revealed Using Virtual Screening by Using a New Deep-Learning Classifier

CYP3A4 is the main human enzyme responsible for phase I metabolism of dietary compounds, prescribed drugs and xenobiotics, steroid hormones, and bile acids. The inhibition of CYP3A4 activity might impair physiological mechanisms, including the endocrine system and response to drug admission. Here, we aimed to discover new CYP3A4 inhibitors from food and dietary supplements. A deep-learning model was built that classifies compounds as either an inhibitor or noninhibitor, with a high specificity of 0.997. We used this classifier to virtually screen ∼60,000 dietary compounds. Of the 115 identified potential inhibitors, only 31 were previously suggested. Many herbals, as predicted here, might cause impaired metabolism of drugs, and endogenous hormones and bile acids. Additionally, by applying Lipinski's rules of five, 17 compounds were also classified as potential intestine local inhibitors. New CYP3A4 inhibitors predicted by the model, bilobetin and picropodophyllin, were assayed in vitro.

New Born Calf Serum Can Induce Spheroid Formation in Breast Cancer KAIMRC1 Cell Line

Three-dimensional (3D) cell culture systems have become very popular in the field of drug screening and discovery. There is an immense demand for highly efficient and easy methods to produce 3D spheroids in any cell format. We have developed a novel and easy method to produce spheroids from the newly isolated KAIMRC1 cell line in vitro. It can be used as a 3D model to study proliferation, differentiation, cell death, and drug response of cancer cells. Our procedure requires growth media supplemented with 10% new born calf serum (NBCS) and regular cell culture plates to generate KAIMRC1 spheroids without the need for any specialized 3D cell culture system. This procedure generates multiple spheroids within a 12–24-h culture. KAIMRC1 spheroids are compact, homogeneous in size and morphology with a mean size of 55.8 µm (±3.5). High content imaging (HCI) of KAIMRC1 spheroids treated with a panel of 240 compounds resulted in the identification of several highly specific compounds towards spheroids. Immunophenotyping of KAIMRC1 spheroids revealed phosphorylation of FAK, cJUN, and E-cadherin, which suggests the involvement of JNK/JUN pathway in the KAIMRC1 spheroids formation. Gene expression analysis showed upregulation of cell junction genes, GJB3, DSC1, CLDN5, CLDN8, and PLAU. Furthermore, co-culture of KAIMRC1 cells with primary cancer-associated-fibroblasts (CAFs) showcased the potential of these cells in drug discovery application.

Abnormally elevated ubiquilin‑1 expression in breast cancer regulates metastasis and stemness via AKT signaling

Ubiquilin-1 (UBQLN1) is an essential factor for the maintenance of proteostasis in cells. It is important for the regulation of different protein degradation mechanisms, including the ubiquitin-proteasome system, autophagy and endoplasmic reticulum-associated protein degradation pathways. However, the role of UBQLN1 in cancer progression remains largely unknown. In the present study, the expression, functions and molecular mechanisms of UBQLN1 in breast cancer tissue samples and cell lines were explored. Immunohistochemical and bioinformatics analyses revealed that UBQLN1 expression was significantly upregulated in breast cancer tissues and cell lines. UBQLN1 expression in breast cancer was significantly associated with lymph node metastasis and TNM stage. Moreover, a high UBQLN1 expression was a predictor of an unfavorable survival in patients with breast cancer. In vitro, UBQLN1 silencing markedly inhibited cell migration and invasion, epithelial-to-mesenchymal transition (EMT) and MMP expression. UBQLN1 silencing attenuated the stem cell-like properties of breast cancer cells, including their mammosphere-forming abilities. UBQLN1 knockdown also enhanced breast cancer cell chemosensitivity to paclitaxel. The expression levels of the stem cell markers. Aldehyde dehydrogenase 1 (ALDH1), Oct-4 and Sox2 were significantly decreased in the cells in which UBQLN1 was silenced, whereas breast cancer stem cells exhibited an increased expression of UBQLN1. Mechanistically, UBQLN1 knockdown inhibited the activation of AKT signaling, as revealed by the increased PTEN expression and the decreased expression of phosphorylated AKT in cells in which UBQLN1 was silenced. On the whole, the present study demonstrates that UBQLN1 is aberrantly upregulated in breast cancer and predicts a poor prognosis. The silencing of UBQLN1 inhibited the invasion, EMT and stemness of breast cancer cells, possibly via AKT signaling.

Unraveling the IGF System Interactome in Sarcomas Exploits Novel Therapeutic Options

Aberrant bioactivity of the insulin-like growth factor (IGF) system results in the development and progression of several pathologic conditions including cancer. Preclinical studies have shown promising anti-cancer therapeutic potentials for anti-IGF targeted therapies. However, a clear but limited clinical benefit was observed only in a minority of patients with sarcomas. The molecular complexity of the IGF system, which comprises multiple regulators and interactions with other cancer-related pathways, poses a major limitation in the use of anti-IGF agents and supports the need of combinatorial therapeutic strategies to better tackle this axis. In this review, we will initially highlight multiple mechanisms underlying IGF dysregulation in cancer and then focus on the impact of the IGF system and its complexity in sarcoma development and progression as well as response to anti-IGF therapies. We will also discuss the role of Ephrin receptors, Hippo pathway, BET proteins and CXCR4 signaling, as mediators of sarcoma malignancy and relevant interactors with the IGF system in tumor cells. A deeper understanding of these molecular interactions might provide the rationale for novel and more effective therapeutic combinations to treat sarcomas.