Fibroblast growth factor signaling in tumorigenesis

FGF2 Mediated USP42-PPARγ Axis Activation Ameliorates Liver Oxidative Damage and Promotes Regeneration

Liver regeneration is critical for maintaining whole-body homeostasis, especially under exposure to deadly chemical toxins. Understanding the molecular mechanisms underlying liver repair is critical for the development of intervention strategies to treat liver diseases. In this study, ubiquitin-specific Proteases 42 (USP42) is identified as a novel deubiquitinases (DUB) of peroxisome proliferators-activated receptor γ (PPARγ) in hepatocytes. This DUB interacted, deubiquitinated, and stabilized PPARγ, and increased PPARγ targeted proliferative and antioxidative gene expressions, which protects the liver from carbon tetrachloride (CCL4) induced oxidative injury and promotes liver regeneration. In addition, fibroblast growth factor 2 (FGF2) initiated USP42 expression and enhanced the interaction between USP42 and PPARγ during the liver regeneration process. Moreover, the PPARγ full agonist, rosiglitazone (RSG), possesses the ability to further reinforce the USP42-PPARγ interplay, which enlightens to construct of an extracellular vesicle-based targeting strategy to activate the liver USP42-PPARγ axis and promote liver regeneration. In summary, the work uncovers the importance of USP42-PPARγ axis-mediated liver tissue homeostasis and provides a promising regimen to target this protein-protein interplay for liver regeneration.

FGFR2 in the Development and Progression of Cutaneous Squamous Cell Cancer

Cutaneous squamous cell carcinoma (cSCC) is an increasingly common malignancy of the skin and the leading cause of death from skin cancer in adults over the age of 85. Fibroblast growth factor receptor 2 (FGFR2) has been identified as an important effector of signaling pathways that lead to the growth and development of cSCC. In recent years, there have been numerous studies evaluating the role FGFR2 plays in multiple cancers, its contribution to resistance to anticancer therapy, and new drugs that may be used to inhibit FGFR2. This review will provide an overview of our current understanding of FGFR2 and potential mechanisms in which we can target FGFR2 in cSCC. The goals of this review are the following: (1) to highlight our current knowledge of the role of FGFR2 in healthy skin and contrast this with its role in the development of cancer; (2) to further explain the specific molecular mechanisms that FGFR2 uses to promote tumorigenesis; (3) to describe how FGFR2 contributes to more invasive disease; (4) to describe its immunosuppressive effects in skin; and (5) to evaluate its effect on current anticancer therapy and discuss therapies on the horizon to target FGFR2 related malignancy.

Landscape of targeted therapies for lung squamous cell carcinoma

Lung cancer, a common type of malignant neoplasm, has seen significant advancements in the treatment of lung adenocarcinoma (LUAD). However, the management of lung squamous cell carcinoma (LSCC) continues to pose challenges. Traditional treatment methods for LSCC encompass surgical resection, chemotherapy, and radiotherapy. The introduction of targeted therapy and immunotherapy has greatly benefited LSCC patients, but issues such as limited immune response rates and adverse reactions persist. Therefore, gaining a deeper comprehension of the underlying mechanisms holds immense importance. This review provides an in-depth overview of classical signaling pathways and therapeutic targets, including the PI3K signaling pathway, CDK4/6 pathway, FGFR1 pathway and EGFR pathway. Additionally, we delve into alternative signaling pathways and potential targets that could offer new therapeutic avenues for LSCC. Lastly, we summarize the latest advancements in targeted therapy combined with immune checkpoint blockade (ICB) therapy for LSCC and discuss the prospects and challenges in this field.

Understanding genetic variations associated with familial breast cancer

BACKGROUND

Breast cancer is the most frequent cancer among women. Genetics are the main risk factor for breast cancer. Statistics show that 15-25% of breast cancers are inherited among those with cancer-prone relatives. BRCA1, BRCA2, TP53, CDH1, PTEN, and STK11 are the most frequent genes for familial breast cancer, which occurs 80% of the time. In rare situations, moderate-penetrance gene mutations such CHEK2, BRIP1, ATM, and PALB2 contribute 2-3%.

METHODS

A search of the PubMed database was carried out spanning from 2005 to July 2024, yielding a total of 768 articles that delve into the realm of familial breast cancer, concerning genes and genetic syndromes. After exclusion 150 articles were included in the final review.

RESULTS

We report on a set of 20 familial breast cancer -associated genes into high, moderate, and low penetrance levels. Additionally, 10 genetic disorders were found to be linked with familial breast cancer.

CONCLUSION

Familial breast cancer has been linked to several genetic diseases and mutations, according to studies. Screening for genetic disorders is recommended by National Comprehensive Cancer Network recommendations. Evaluation of breast cancer candidate variations and risk loci may improve individual risk assessment. Only high- and moderate-risk gene variations have clinical guidelines, whereas low-risk gene variants require additional investigation. With increasing use of NGS technology, more linkage with rare genes is being discovered.

Primer on FGF3

Though initially discovered as a proto-oncogene in virally induced mouse mammary tumors, FGF3 is primarily active in prenatal stages, where it is found at various sites at specific times. FGF3 is crucial during development, as its roles include tail formation, inner ear development and hindbrain induction and patterning. FGF3 expression and function are highly conserved in vertebrates, while it also interacts with other FGFs in various developmental processes. Intriguingly, while it is classified as a classical paracrine signaling factor, murine FGF3 was uniquely found to also act in an intracrine manner, depending on alternative translation initiation sites. Corresponding with its conserved role in inner ear morphogenesis, mutations in FGF3 in humans are associated with LAMM syndrome, a disorder that include hearing loss and inner ear malformations. While recent studies indicate of some FGF3 presence in post-natal stages, emerging evidences of its upregulation in various human tumors and cariogenic processes in mouse models, highlights the importance of its close regulation in adult tissues. Altogether, the broad and dynamic expression pattern and regulation of FGF3 in embryonic and adult tissues together with its link to congenital malformations and cancer, calls for further discoveries of its diverse roles in health and disease.

Deciphering the FGFR2 Code: Innovative Targets in Gastric Cancer Therapy

Gastric cancer (GC) represents a major global health challenge as a highly prevalent disease with high mortality whose global incidence and mortality are predicted to worsen over the coming years. To date, our standard of care for advanced gastric cancer of combination chemotherapy and immunotherapy has a 1-year overall survival rate of 55%. Significant efforts have gone into identifying targetable alterations in gastric cancer, ultimately yielding the Fibroblast Growth Factor Receptors (FGFRs) family, specifically FGFR2 as a promising target. FGFR2 is overexpressed in GC, particularly diffuse-type GC, and is associated with poor prognostic outcomes. In recent years, there has been an increasing number of small molecule inhibitors and monoclonal antibodies targeting FGFR2 that have entered into clinical trials. Specifically for GC, these agents are currently being trialed in various phases as monotherapies or with standard-of-care treatments to make a clinically meaningful impact on what appears to be an important biological axis of GC. In this review, we outline the underlying biology of FGFR2, its putative role in GC, and the various FGFR2-targeted agents currently in clinical trials for gastric cancer patients as well as postulate some challenges in adopting these therapeutics for clinically meaningful benefit.

Causal relationship between endometrial cancer and risk of breast cancer: A 2-sample Mendelian randomization study

Several studies have confirmed the important role of endometrial cancer (EC) in the development and progression of breast cancer (BC), and this study will explore the causal relationship between EC and BC by 2-sample Mendelian randomization analysis. Pooled data from published genome-wide association studies were used to assess the association between EC and BC risk in women using 5 methods, namely, inverse variance weighting (IVW), MR-Egger, weighted median (WME), simple multimaximetry (SM) and weighted multimaximetry (WM) with the EC-associated genetic loci as the instrumental variables (IV) and sensitivity analyses were used to assess the robustness of the results. The statistical results showed a causal association between EC and BC (IVW: OR = 1.07, 95% CI = 1.01-1.32, P = .02; MR-Egger: OR = 1.21, 95% CI = 0.71-1.51, P = .11; weighted median: OR = 1.05, 95% CI = 0.97-1.31, P = .19; simple plurality method: OR = 0.98, 95% CI = 0.81-1.15, P = .78; weighted plurality method: OR = 0.98, 95% CI = 0.81-1.14, P = .75), and the results of the sensitivity analyses showed that there was no significant heterogeneity or multiplicity, and the results were stable. EC is associated with an increased risk of developing BC. The results of this MR analysis can be used as a guideline for screening for BC in women with EC and to help raise awareness of screening for early detection and treatment.

Fibroblast growth factor 5 expression predicts the progression of oral squamous cell carcinoma

BACKGROUND/PURPOSE

Fibroblast growth factor (FGF) 5 is a member of the FGF family that functions as a regulator of tissue growth and regeneration. Aberrant FGF5 expression has been previously associated with the progression of a number of different malignancies. However, its potential role in oral cancer remains unclear. In this study, we explored the relationship between the expression of FGF5 protein in oral squamous cell carcinomas (OSCCs) and the clinicopathological parameters of OSCCs and whether the expression of FGF5 protein in OSCCs could be a prognostic factor for OSCC patients.

METHODS

The FGF5 protein expression was examined in 64 OSCC and 34 normal oral mucosal specimens by immunohistochemical staining. Stress induced upregulation and intracellular redistribution of FGF5 were verified using xenograft animal model and OSCC cell lines.

RESULTS

The mean FGF5 protein labelling index was significantly higher in OSCC than in normal oral mucosal samples, with high FGF5 protein labelling index (>58%) being correlated with advanced stage and poor survival of OSCC patients. Apart from the peri-cytoplasmic staining pattern characteristic of paracrine growth factors, FGF5 protein was localized as distinct punctate structures in the cytoplasm of advanced stage or stressed-induced cells. This redistribution and upregulation of FGF5 protein could be sustained after termination of the stress induction in cell line and xenograft animal models.

CONCLUSION

FGF5 can be induced by cellular stress and risk factors of OSCC, where high expression levels of FGF5 is potentially a useful parameter for predicting OSCC progression and patient survival.

A novel FGFR1 inhibitor CYY292 suppresses tumor progression, invasion, and metastasis of glioblastoma by inhibiting the Akt/GSK3β/snail signaling axis

Glioblastoma (GBM) is a malignant brain tumor that grows quickly, spreads widely, and is resistant to treatment. Fibroblast growth factor receptor (FGFR)1 is a receptor tyrosine kinase that regulates cellular processes, including proliferation, survival, migration, and differentiation. FGFR1 was predominantly expressed in GBM tissues, and FGFR1 expression was negatively correlated with overall survival. We rationally designed a novel small molecule CYY292, which exhibited a strong affinity for the FGFR1 protein in GBM cell lines in vitro. CYY292 also exerted an effect on the conserved Ser777 residue of FGFR1. CYY292 dose-dependently inhibited cell proliferation, epithelial-mesenchymal transition, stemness, invasion, and migration in vitro by specifically targeting the FGFR1/AKT/Snail pathways in GBM cells, and this effect was prevented by pharmacological inhibitors and critical gene knockdown. In vivo experiments revealed that CYY292 inhibited U87MG tumor growth more effectively than AZD4547. CYY292 also efficiently reduced GBM cell proliferation and increased survival in orthotopic GBM models. This study further elucidates the function of FGFR1 in the GBM and reveals the effect of CYY292, which targets FGFR1, on downstream signaling pathways directly reducing GBM cell growth, invasion, and metastasis and thus impairing the recruitment, activation, and function of immune cells.

Identification of antisense and sense RNAs of intracrine fibroblast growth factor components as novel biomarkers in colorectal cancer and in silico studies for drug and nanodrug repurposing

INTRODUCTION

Colorectal cancer (CRC) is one of the most malignant tumors and in which various efforts for screening is inconclusive.The intracrine FGF panel, the non-tyrosine kinase receptors (NTKR) FGFs and affiliated antisenses play a pivotal role in FGF signaling.The expression levels of coding and non-coding intracrine FGFs were assessed in CRC donors.Also, substantial costs and slow pace of drug discovery give high attraction to repurpose of previously discovered drugs to new opportunities.

OBJECTIVES

The aim of present study was to evaluate the potential role of the coding and non-coding intracrine FGFs as a new biomarkers for CRC cases and defining drug repurposing to alleviate FGF down regulation.

METHODS

RNA-seq data of colon adenocarcinomas (COAD) was downloaded using TCGA biolinks package in R.The DrugBank database (https://go.drugbank.com/) was used to extract interactions between drugs and candidate genes. A total of 200 CRC patients with detailed criteria were enrolled.RNAs were extracted with TRIzol-based protocol and amplified via LightCycler® instrument.FGF11 and FGF13 proteins validation was performed by used of immunohistochemistry technique in tumor and non-tumoral samples.Pearson's correlation analysis and ROC curve plotted by Prism 8.0 software.

RESULTS

RNA-seq data from TCGA was analyzed by normalizing with edgeR.Differentially expressed gene (DEG) analysis was generated. WCC algorithm extracted the most significant genes with a total of 47 genes. Expression elevation of iFGF antisenses (12AS,13As,14AS) compared with the normal colon tissue were observed (P = 0.0003,P = 0.042,P = 0.026, respectively). Moreover,a significant decrease in expression of the corresponding sense iFGF genes was detected (P < 0.0001).Plotted receiver operating characteristic (ROC) curves for iFGF components' expression showed an area of over 0.70 (FGF11-13: 0.71% and FGF12-14: 0.78%, P < 0.001) for sense mRNA expression, with the highest sensitivity for FGF12 (92.8%) and lowest for FGF11 (61.41%).The artificial intelligence (AI) revealed the valproic acid as a repurposing drug to relief the down regulation of FGF12 and 13 in CRC patients.

CONCLUSION

Intracrine FGFs panel was down regulated versus up regulation of dependent antisenses. Thus, developing novel biomarkers based on iFGF can be considered as a promising strategy for CRC screening.In advanced, valporic acid detected by AI as a repurposing drug which may be applied in clinical trials for CRC treatment.

Single-nucleotide variants within heart enhancers increase binding affinity and disrupt heart development

Transcriptional enhancers direct precise gene expression patterns during development and harbor the majority of variants associated with phenotypic diversity, evolutionary adaptations, and disease. Pinpointing which enhancer variants contribute to changes in gene expression and phenotypes is a major challenge. Here, we find that suboptimal or low-affinity binding sites are necessary for precise gene expression during heart development. Single-nucleotide variants (SNVs) can optimize the affinity of ETS binding sites, causing gain-of-function (GOF) gene expression, cell migration defects, and phenotypes as severe as extra beating hearts in the marine chordate Ciona robusta. In human induced pluripotent stem cell (iPSC)-derived cardiomyocytes, a SNV within a human GATA4 enhancer increases ETS binding affinity and causes GOF enhancer activity. The prevalence of suboptimal-affinity sites within enhancers creates a vulnerability whereby affinity-optimizing SNVs can lead to GOF gene expression, changes in cellular identity, and organismal-level phenotypes that could contribute to the evolution of novel traits or diseases.

Exploiting the fibroblast growth factor receptor-1 vulnerability to therapeutically restrict the MYC-EZH2-CDKN1C axis-driven proliferation in Mantle cell lymphoma

Mantle cell lymphoma (MCL) is a lethal hematological malignancy with a median survival of 4 years. Its lethality is mainly attributed to a limited understanding of clinical tumor progression and resistance to current therapeutic regimes. Intrinsic, prolonged drug treatment and tumor-microenvironment (TME) facilitated factors impart pro-tumorigenic and drug-insensitivity properties to MCL cells. Hence, elucidating neoteric pharmacotherapeutic molecular targets involved in MCL progression utilizing a global "unified" analysis for improved disease prevention is an earnest need. Using integrated transcriptomic analyses in MCL patients, we identified a Fibroblast Growth Factor Receptor-1 (FGFR1), and analyses of MCL patient samples showed that high FGFR1 expression was associated with shorter overall survival in MCL patient cohorts. Functional studies using pharmacological intervention and loss of function identify a novel MYC-EZH2-CDKN1C axis-driven proliferation in MCL. Further, pharmacological targeting with erdafitinib, a selective small molecule targeting FGFRs, induced cell-cycle arrest and cell death in-vitro, inhibited tumor progression, and improved overall survival in-vivo. We performed extensive pre-clinical assessments in multiple in-vivo model systems to confirm the therapeutic potential of erdafitinib in MCL and demonstrated FGFR1 as a viable therapeutic target in MCL.

Role of Fibroblast Growth Factor Receptor 2 (FGFR2) in Corneal Stromal Thinning

Purpose

To determine the role of fibroblast growth factor receptor 2 (FGFR2)-mediated signaling in keratocytes during corneal development, a keratocyte-specific FGFR2-knockout (named FGFR2cKO) mouse model was generated, and its phenotypic characteristics were determined.

Methods

A FGFR2cKO mouse model was generated by the following method: FGFR2 flox mice were crossed with the inducible keratocyte specific-Cre mice (Kera-rtTA/tet-O-Cre). Both male and female FGFR2cKO- and control mice (1 to 3-months-old) were analyzed for changes in corneal topography and pachymetry maps using the optical coherence tomography (OCT) method. The comparative TUNEL assay and immunohistochemical analyses were performed using corneas of FGFR2cKO and control mice to determine apoptotic cells, and expression of collagen-1 and fibronectin. Transmission electron microscopic analysis was conducted to determine collagen structures and their diameters in corneas of FGFR2cKO and control mice.

Results

OCT-analyses of corneas of FGFR2cKO mice (n = 24) showed localized central thinning and an increased corneal steepness compared to control mice (n = 23). FGFR2cKO mice further showed a decreased expression in collagen-1, decreased collagen diameters, acute corneal hydrops, an increased fibronectin expression, and an increased number of TUNEL-positive cells suggesting altered collagen structures and keratocytes' apoptosis in the corneas of FGFR2cKO mice compared to control mice.

Conclusions

The FGFR2cKO mice showed several corneal phenotypes (as described above in the results) that are also exhibited by the human keratoconus corneas. The results suggested that the FGFR2cKO mouse model serves to elucidate not only the yet unknown role of FGFR2-mediated signaling in corneal physiology but also serves as a model to determine molecular mechanism of human keratoconus development.

Crosstalk between Thyroid Carcinoma and Tumor-Correlated Immune Cells in the Tumor Microenvironment

Thyroid cancer (TC) is the most common malignancy in the endocrine system. Although most TC can achieve a desirable prognosis, some refractory thyroid carcinomas, including radioiodine-refractory differentiated thyroid cancer, as well as anaplastic thyroid carcinoma, face a myriad of difficulties in clinical treatment. These types of tumors contribute to the majority of TC deaths due to limited initial therapy, recurrence, and metastasis of the tumor and tumor resistance to current clinically targeted drugs, which ultimately lead to treatment failure. At present, a growing number of studies have demonstrated crosstalk between TC and tumor-associated immune cells, which affects tumor deterioration and metastasis through distinct signal transduction or receptor activation. Current immunotherapy focuses primarily on cutting off the interaction between tumor cells and immune cells. Since the advent of immunotherapy, scholars have discovered targets for TC immunotherapy, which also provides new strategies for TC treatment. This review methodically and intensively summarizes the current understanding and mechanism of the crosstalk between distinct types of TC and immune cells, as well as potential immunotherapy strategies and clinical research results in the area of the tumor immune microenvironment. We aim to explore the current research advances to formulate better individualized treatment strategies for TC patients and to provide clues and references for the study of potential immune checkpoints and the development of immunotherapy technologies.

Exploring the molecular pathways and therapeutic implications of angiogenesis in neuropathic pain

Recently, much attention has been paid to chronic neuro-inflammatory condition underlying neuropathic pain. It is generally linked with thermal hyperalgesia and tactile allodynia. It results due to injury or infection in the nervous system. The neuropathic pain spectrum covers a variety of pathophysiological states, mostly involved are ischemic injury viral infections associated neuropathies, chemotherapy-induced peripheral neuropathies, autoimmune disorders, traumatic origin, hereditary neuropathies, inflammatory disorders, and channelopathies. In CNS, angiogenesis is evident in inflammation of neurons and pain in bone cancer. The role of chemokines and cytokines is dualistic; their aggressive secretion produces detrimental effects, leading to neuropathic pain. However, whether the angiogenesis contributes and exists in neuropathic pain remains doubtful. In the present review, we elucidated summary of diverse mechanisms of neuropathic pain associated with angiogenesis. Moreover, an overview of multiple targets that have provided insights on the VEGF signaling, signaling through Tie-1 and Tie-2 receptor, erythropoietin pathway promoting axonal growth are also discussed. Because angiogenesis as a result of these signaling, results in inflammation, we focused on the mechanisms of neuropathic pain. These factors are mainly responsible for the activation of post-traumatic regeneration of the PNS and CNS. Furthermore, we also reviewed synthetic and herbal treatments targeting angiogenesis in neuropathic pain.

Molecular Signature of Biological Aggressiveness in Clear Cell Sarcoma of the Kidney (CCSK)

Clear cell sarcoma of the kidney (CCSK) is a rare pediatric renal tumor with a worse prognosis than Wilms' tumor. Although recently, BCOR internal tandem duplication (ITD) has been found as a driver mutation in more than 80% of cases, a deep molecular characterization of this tumor is still lacking, as well as its correlation with the clinical course. The aim of this study was to investigate the differential molecular signature between metastatic and localized BCOR-ITD-positive CCSK at diagnosis. Whole-exome sequencing (WES) and whole-transcriptome sequencing (WTS) were performed on six localized and three metastatic BCOR-ITD-positive CCSKs, confirming that this tumor carries a low mutational burden. No significant recurrences of somatic or germline mutations other than BCOR-ITD were identified among the evaluated samples. Supervised analysis of gene expression data showed enrichment of hundreds of genes, with a significant overrepresentation of the MAPK signaling pathway in metastatic cases (p < 0.0001). Within the molecular signature of metastatic CCSK, five genes were highly and significantly over-expressed: FGF3, VEGFA, SPP1, ADM, and JUND. The role of FGF3 in the acquisition of a more aggressive phenotype was investigated in a cell model system obtained by introducing the ITD into the last exon of BCOR by Crispr/Cas9 gene editing of the HEK-293 cell line. Treatment with FGF3 of BCOR-ITD HEK-293 cell line induced a significant increase in cell migration versus both untreated and scramble cell clone. The identification of over-expressed genes in metastatic CCSKs, with a particular focus on FGF3, could offer new prognostic and therapeutic targets in more aggressive cases.

Fascin is essential for mammary gland lactogenesis

Fascin expression has commonly been observed in certain subtypes of breast cancer, where its expression is associated with poor clinical outcome. However, its role in normal mammary gland development has not been elucidated. Here, we used a fascin knockout mouse model to assess its role in normal mammary gland morphogenesis and lactation. Fascin knockout was not embryonically lethal, and its effect on the litter size or condition at birth was minimal. However, litter survival until the weaning stage significantly depended on fascin expression solely in the nursing dams. Accordingly, pups that nursed from fascin^-/- dams had smaller milk spots in their abdomen, suggesting a lactation defect in the nursing dams. Mammary gland whole-mounts of pregnant and lactating fascin^-/- mice showed significantly reduced side branching and alveologenesis. Despite a typical composition of basal, luminal, and stromal subsets of mammary cells and normal ductal architecture of myoepithelial and luminal layers, the percentage of alveolar progenitors (ALDH⁺) in fascin^-/- epithelial fraction was significantly reduced. Further in-depth analyses of fascin^-/- mammary glands showed a significant reduction in the expression of Elf5, the master regulator of alveologenesis, and a decrease in the activity of its downstream target p-STAT5. In agreement, there was a significant reduction in the expression of the milk proteins, whey acidic protein (WAP), and β-casein in fascin^-/- mammary glands. Collectively, our data demonstrate, for the first time, the physiological role of fascin in normal mammary gland lactogenesis, an addition that could reveal its contribution to breast cancer initiation and progression.

A novel small molecule RK-019 inhibits FGFR2-amplification gastric cancer cell proliferation and induces apoptosis in vitro and in vivo

Gastric cancer (GC) is one of the most malignant cancers and is estimated to be fifth in incidence ratio and the third leading cause of cancer death worldwide. Despite advances in GC treatment, poor prognosis and low survival rate necessitate the development of novel treatment options. Fibroblast growth factor receptors (FGFRs) have been suggested to be potential targets for GC treatment. In this study, we report a novel selective FGFR inhibitor, RK-019, with a pyrido [1, 2-a] pyrimidinone skeleton. In vitro, RK-019 showed excellent FGFR1-4 inhibitory activities and strong anti-proliferative effects against FGFR2-amplification (FGFR2-amp) GC cells, including SNU-16 and KATO III cells. Treatment with RK-019 suppressed phosphorylation of FGFR and its downstream pathway proteins, such as FRS2, PLCγ, AKT, and Erk, resulting in cell cycle arrest and induction of apoptosis. Furthermore, daily oral administration of RK-019 could attenuate tumor xenograft growth with no adverse effects. Here, we reported a novel specific FGFR inhibitor, RK-019, with potent anti-FGFR2-amp GC activity both in vitro and in vivo.

FGF/FGFR signaling in adrenocortical development and tumorigenesis: novel potential therapeutic targets in adrenocortical carcinoma

FGF/FGFR signaling regulates embryogenesis, angiogenesis, tissue homeostasis and wound repair by modulating proliferation, differentiation, survival, migration and metabolism of target cells. Understandably, compelling evidence for deregulated FGF signaling in the development and progression of different types of tumors continue to emerge and FGFR inhibitors arise as potential targeted therapeutic agents, particularly in tumors harboring aberrant FGFR signaling. There is first evidence of a dual role of the FGF/FGFR system in both organogenesis and tumorigenesis, of which this review aims to provide an overview. FGF-1 and FGF-2 are expressed in the adrenal cortex and are the most powerful mitogens for adrenocortical cells. Physiologically, they are involved in development and maintenance of the adrenal gland and bind to a family of four tyrosine kinase receptors, among which FGFR1 and FGFR4 are the most strongly expressed in the adrenal cortex. The repeatedly proven overexpression of these two FGFRs also in adrenocortical cancer is thus likely a sign of their participation in proliferation and vascularization, though the exact downstream mechanisms are not yet elucidated. Thus, FGFRs potentially offer novel therapeutic targets also for adrenocortical carcinoma, a type of cancer resistant to conventional antimitotic agents.

Characterization of the cholangiocarcinoma drug pemigatinib against FGFR gatekeeper mutants

Fibroblast growth factor receptor (FGFR) dysregulation is involved in a variety of tumorigenesis and development. Cholangiocarcinoma is closely related with FGFR aberrations, and pemigatinib is the first drug approved to target FGFR for the treatment of cholangiocarcinoma. Herein, we undertake biochemical and structural analysis on pemigatinib against FGFRs as well as gatekeeper mutations. The results show that pemigatinib is a potent and selective FGFR1-3 inhibitor. The extensive network of hydrogen bonds and van der Waals contacts found in the FGFR1-pemigatinib binding mode accounts for the high potency. Pemigatinib also has excellent potency against the Val-to-Ile gatekeeper mutation but less potency against the Val-to-Met/Phe gatekeeper mutation in FGFR. Taken together, the inhibitory and structural profiles exemplified by pemigatinib may help to thwart Val-to-Ile gatekeeper mutation-based resistance at earlier administration and to advance the further design and improvement for inhibitors toward FGFRs with gatekeeper mutations.

A repositioning screen using an FGFR2 splicing reporter reveals compounds that regulate epithelial-mesenchymal transitions and inhibit growth of prostate cancer xenografts

Research in the area of hallmarks of cancer has opened the possibility of designing new therapies based on modulating these cancer properties. We present here a screen designed to find chemicals that modulate epithelial-mesenchymal transitions (EMTs) in prostate cancer. For screening, we used a repurposing library and, as a readout, an FGFR2-based splicing reporter, which has been shown previously to be a sensor for EMTs. Various properties of cancer cells were assessed, signaling pathways investigated, and in vivo experiments in nude mice xenografts performed. The screen yielded three hit compounds (a T-type Ca channel inhibitor, an L-type Ca channel inhibitor, and an opioid antagonist) that switch FGFR2 splicing and induce an epithelial phenotype in prostate cancer cells. The compounds affected differently various properties of cancer cells, but all of them decreased cell migration, which is in line with modulating EMTs. We further present mechanistic insights into one of the compounds, nemadipine-A. The administration of nemadipine-A intraperitoneally in a nude mouse xenograft model of prostate cancer slowed tumor growth. To conclude, we show that knowledge of the molecular mechanisms that connect alternative splicing and various cancer properties may be used as a platform for drug development.

Inhibition of Fibroblast Growth Factor Receptor Attenuates Ultraviolet B-Induced Skin Carcinogenesis

Altered FGFR signaling has been shown to play a role in a number of cancers. However, the role of FGFR signaling in the development and progression of ultraviolet B-induced (UVB) induced cutaneous squamous cell carcinoma (cSCC) remains unclear. In the current study, the effect of UVB radiation on FGFR activation and its downstream signaling in mouse skin epidermis was examined. In addition, the impact of FGFR inhibition on UVB-induced signaling and skin carcinogenesis was also investigated. Exposure of mouse dorsal skin to UVB significantly increased phosphorylation of FGFRs in the epidermis as well as activation of downstream signaling pathways, including AKT/mTOR, STATs and MAPK. Topical application of the pan-FGFR inhibitor AZD4547 to mouse skin prior to exposure to UVB significantly inhibited FGFR phosphorylation as well as mTORC1, STAT3 and MAPK activation (i.e., phosphorylation). Moreover, AZD4547 pretreatment significantly inhibited UVB-induced epidermal hyperplasia and hyperproliferation and reduced infiltration of mast cells and macrophages into the dermis. AZD4547 treatment also significantly inhibited mRNA expression of inflammatory genes in the epidermis. Finally, mice treated topically with AZD4547 prior to UVB exposure showed decreased cSCC incidence and increased survival rate. Collectively, the current data supports the hypothesis that inhibition of FGFR in epidermis may provide a new strategy to prevent and/or treat UVB-induced cSCC.

A concise review on tyrosine kinase targeted cancer therapy

Abstract:

The tyrosine kinase (TK) family is considered one of the important family members of the kinase family due to its important role in various cellular processes like cell growth, cell differentiation, apoptosis, etc. Mutation, overexpression, and dysfunction of tyrosine kinase receptors lead to the development of malignancy; thus, they are considered as one of the important targets for the development of anti-cancer molecules. The tyrosine kinase family is majorly divided into two classes; receptor and non-receptor tyrosine kinase. Both of the classes have an important role in the development of tumour cells. Currently, there are more than 40 FDA-approved tyrosine kinase inhibitors, which are used in the treatment of various types of cancers. Tyrosine kinase inhibitors mainly block the phosphorylation of tyrosine residue of the corresponding kinase substrate and so activation of downstream signalling pathways can be inhibited. The promising results of tyrosine kinase inhibitors in solid tumours provide a revolution in oncology research. In this article, we had summarized the role of some important members of the tyrosine kinase family in the development and progression of tumour cells and the significance of tyrosine kinase inhibitors in the treatment of various types of cancer.

Engineering tumor constructs to study matrix-dependent angiogenic signaling of breast cancer cells

Breast cancer is the leading cause of cancer deaths among females globally. The crosstalk between tumor microenvironment and neoplastic cells is the key for promoting tumor growth, stimulating tumor angiogenesis, and metastasis to distant organs. Thus, it is highly important to investigate tumor cell-matrix interactions to facilitate screening of different anti-cancer agents, individually or in combination. We, herein report, the development of an in vitro three-dimensional (3D) breast cancer model to investigate the effect of stromal crosslinking and consequent, stiffening on the angiogenic activity of cancer cells. Crosslinking of collagen gels was altered via non-enzymatic glycation and highly aggressive breast cancer cells, MDA-MB-231, were encapsulated in these gels. Cells encapsulated in glycated/stiffer matrices displayed an increased expression of pro-angiogenesis-related signals. Inhibition of mechanotransduction pathways on the angiogenic activity of aggressive tumor cells in stiff matrices was investigated using Y-27632, blebbistatin, and cytochalasin D. Rho-associated kinase (ROCK) inhibitor, Y-27632, diminished the pro-angiogenic signaling, thereby suggesting the potential dependence of breast cancer cells on the Rho/ROCK pathway in regulating tumor angiogenesis. Our findings highlight the potential of the developed model to be used as a tool to investigate matrix-associated tumor angiogenesis and screen different therapeutic agents towards inhibiting it.

Fibroblast growth factor receptor signalling dysregulation and targeting in breast cancer

Fibroblast Growth Factor Receptor (FGFR) signalling plays a critical role in breast embryonal development, tissue homeostasis, tumorigenesis and metastasis. FGFR, its numerous FGF ligands and signalling partners are often dysregulated in breast cancer progression and are one of the causes of resistance to treatment in breast cancer. Furthermore, FGFR signalling on epithelial cells is affected by signals from the breast microenvironment, therefore increasing the possibility of breast developmental abnormalities or cancer progression. Increasing our understanding of the multi-layered roles of the complex family of FGFRs, their ligands FGFs and their regulatory partners may offer novel treatment strategies for breast cancer patients, as a single agent or rational co-target, which will be explored in depth in this review.

The Obscure Potential of AHNAK2

Simple Summary

AHNAK2 is a relatively newly discovered protein. It can interact with many other proteins. This protein is increased in cells of variety of different cancers. AHNAK2 may play a vital role in cancer formation. AHNAK2 may have a role in early detection of cancer. This obscure potential of AHNAK2 is being studied.

Abstract

AHNAK2 is a protein discovered in 2004, with a strong association with oncogenesis in various epithelial cancers. It has a large 616 kDa tripartite structure and is thought to take part in the formation of large multi-protein complexes. High expression is found in clear cell renal carcinoma, pancreatic ductal adenocarcinoma, uveal melanoma, and lung adenocarcinoma, with a relation to poor prognosis. Little work has been done in exploring the function and relation AHNAK2 has with cancer, with early studies showing promising potential as a future biomarker and therapeutic target.

A validated LC-MS/MS analytical method for the quantification of pemigatinib: metabolic stability evaluation in human liver microsomes

Pemigatinib (PMB) is a small molecule inhibitor of fibroblast growth factor receptor 1 (FGFR1), FGFR2 and FGFR3. On April 17, 2020, the US Food and Drug Administration granted accelerated approval for PMB for the treatment of adults with previously treated, unresectable metastatic or locally advanced cholangiocarcinoma with a fibroblast growth factor receptor 2 (FGFR2) fusion or other rearrangement. PMB is considered the first targeted treatment for cholangiocarcinoma approved in the US. In this study, in silico prediction of PMB metabolic stability was done using the WhichP450 module of the StarDrop software package. Further, an LC-MS/MS analytical method was developed for PMB quantification in human liver microsomes (HLM) to experimentally assess metabolic stability. PMB and flavopiridol (FVL), used as an internal standard IS, were resolved using an isocratic mobile phase and a C18 stationary phase. The LC-MS/MS method showed linearity in the range of 5 to 500 ng mL⁻¹ in an HLM matrix (R² = 0.9995). The lower limit of quantification (LLOQ) was 5 ng mL⁻¹, indicating sensitivity. The inter- and intra-day accuracy and precision were within a variability of 10, confirming the reproducibility of the method. The measured in vitro half-life and intrinsic clearance of PMB were 27.29 min and 25.40 μL min⁻¹ mg⁻¹, respectively. PMB showed a moderate extraction ratio suggesting good bioavailability. The developed analytical method is the first LC-MS/MS method specific for PMB quantification with application to metabolic stability assessment.

PMB showed a moderate extraction ratio suggesting good bioavailability. The developed analytical method is the first LC-MS/MS method specific for PMB quantification with application to metabolic stability assessment.

FGFR4 Gly388Arg Polymorphism Reveals a Poor Prognosis, Especially in Asian Cancer Patients: A Meta-Analysis

The fibroblast growth factor-4 receptor (FGFR4) is a member of receptor tyrosine kinase. The FGFR4 Gly388Arg polymorphism in the transmembrane domain of the receptor has been shown to increase genetic susceptibility to cancers. However, its prognostic impact in cancer patients still remains controversial. Herein, we performed this meta-analysis to evaluate the clinicopathological and prognostic impacts of the FGFR4 Gly388Arg polymorphism in patients with cancer. We carried out a computerized extensive search using PubMed, Medline, and Ovid Medline databases up to July 2021. From 44 studies, 11,574 patients were included in the current meta-analysis. Regardless of the genetic models, there was no significant correlation of the FGFR4 Gly388Arg polymorphism with disease stage 3/4. In the homozygous model (Arg/Arg vs. Gly/Gly), the Arg/Arg genotype tended to show higher rate of lymph node metastasis compared with the Gly/Gly genotype (odds ratio = 1.21, 95% confidence interval (CI): 0.99-1.49, p = 0.06). Compared to patients with the Arg/Gly or Arg/Arg genotype, those with the Gly/Gly genotype had significantly better overall survival (hazard ratios (HR) = 1.19, 95% CI: 1.05-1.35, p = 0.006) and disease-free survival (HR = 1.25, 95% CI: 1.03-1.53, p = 0.02). In conclusion, this meta-analysis showed that the FGFR4 Gly388Arg polymorphism was significantly associated with worse prognosis in cancer patients. Our results suggest that this polymorphism may be a valuable genetic marker to identify patients at higher risk of recurrence or mortality.

A Large Central Bronchopleural Fistula Closed by Bronchoscopic Administration of Recombinant Bovine Basic Fibroblast Growth Factor: A Case Report

A large central bronchopleural fistula (BPF) surrounded by mediastinal tissue was successfully closed by local administration of recombinant bovine basic fibroblast growth factor (rbFGF) using the bronchoscope. No complications were observed during and after this bronchoscopic treatment. This is the first report of the bronchoscopic treatment of a large central BPF by the local spray of rbFGF. The bronchoscopic treatment with rbFGF is a potentially cost-effective method for central BPF surrounded by mediastinal tissue.

DYRK1A is required for maintenance of cancer stemness, contributing to tumorigenic potential in oral/oropharyngeal squamous cell carcinoma

DYRK1A, one of the dual-specificity tyrosine phosphorylation-regulated kinases (DYRKs), plays an important role in various biological processes by regulating downstream targets via kinase-dependent and independent mechanisms. Here, we report a novel role of DYRK1A in maintaining tumor growth and stemness of oral/oropharyngeal squamous cell carcinoma (OSCC) cells. Deletion of DYRK1A from OSCC cells abrogated their in vivo tumorigenicity and self-renewal capacity, the key features of cancer stem-like cells (CSCs; also referred to as tumor-initiating cells). The DYRK1A deletion also induced the suppression of CSC populations and properties, such as migration ability and chemoresistance. Conversely, ectopic expression of DYRK1A in OSCC cells augmented their CSC phenotype. Among five DYRK members (DYRK1A, 1B, 2, 3, and 4), DYRK1A is the most dominantly expressed kinase, and its expression is upregulated in OSCC compared to normal oral epithelial cells. More importantly, DYRK1A was highly enriched in various CSC-enriched OSCC populations compared to their corresponding non-CSC populations, indicating its pivotal role in cancer progression and stemness. Further, our study revealed that fibroblast growth factor 2 (FGF2) is a key regulator in the DYRK1A-mediated CSC regulation. Functional studies demonstrated that the loss of DYRK1A inhibits CSC phenotype via reduction of FGF2. Overexpression of DYRK1A promotes CSC phenotype via upregulation of FGF2. Our study delineates a novel mechanism of cancer stemness regulation by DYRK1A-FGF2 axis in OSCC. Thus, inhibition of DYRK1A would lead to a potential novel therapeutic option for targeting CSCs in OSCC.

Discovery of Pemigatinib: A Potent and Selective Fibroblast Growth Factor Receptor (FGFR) Inhibitor

Aberrant activation of FGFR has been linked to the pathogenesis of many tumor types. Selective inhibition of FGFR has emerged as a promising approach for cancer treatment. Herein, we describe the discovery of compound 38 (INCB054828, pemigatinib), a highly potent and selective inhibitor of FGFR1, FGFR2, and FGFR3 with excellent physiochemical properties and pharmacokinetic profiles. Pemigatinib has received accelerated approval from the U.S. Food and Drug Administration for the treatment of adults with previously treated, unresectable locally advanced or metastatic cholangiocarcinoma with a FGFR2 fusion or other rearrangement. Additional clinical trials are ongoing to evaluate pemigatinib in patients with FGFR alterations.

Differential expression of phosphorylated MEK and ERK correlates with aggressive BCC subtypes

Basal cell carcinoma (BCC) is associated with aberrant Hedgehog (HH) signalling through mutational inactivation of PTCH1; however, there is conflicting data regarding MEK/ERK signalling in BCC and the signalling pathway interactions in these carcinomas. To address this, expression of active phospho (p) MEK and ERK was examined in a panel of 15 non-aggressive and 14 aggressive BCCs. Although not uniformly expressed, both phospho-proteins were detected in the nuclei and/or cytoplasm of normal and tumour-associated epidermal cells however, whereas phospho-MEK (pMEK) was present in all non-aggressive BCCs (14/14), phospho-ERK (pERK) was rarely expressed (2/14). In contrast pERK expression was more prevalent in aggressive tumours (11/14). Interestingly, pMEK was only localized to the tumour mass whereas pERK was expressed in tumours and stroma of aggressive BCCs. Similarly, pERK (but not pMEK) was absent in mouse BCC-like tumours derived from X-ray irradiated Ptch1+/- mice with stromal pERK observed in myofibroblasts of the aggressive variant as well as in the tumour mass. RNA sequencing analysis of tumour epithelium and stroma of aggressive and non-aggressive BCC revealed the upregulation of epidermal growth factor receptor- and ERK-related pathways. Angiogenesis and immune response pathways were also upregulated in the stroma compared with the tumour. PTCH1 suppressed NEB1 immortalized keratinocytes (shPTCH1) display upregulated pERK that can be independent of MEK expression. Furthermore, epidermal growth factor pathway inhibitors affect the HH pathway by suppressing GLI1. These studies reveal differential expression of pERK between human BCC subtypes that maybe active by a pathway independent of MEK.

Integrated analysis of DNA methylation and mRNA expression profiles to identify key genes in head and neck squamous cell carcinoma

DNA methylation has been demonstrated to play significant roles in the etiology and pathogenesis of head and neck squamous cell carcinoma (HNSCC). In the present study, methylation microarray dataset (GSE87053) and gene expression microarray dataset (GSE23558) were downloaded from GEO database and analyzed through R language. A total of 255 hypermethylated-downregulated genes and 114 hypomethylated-upregulated genes were finally identified. Functional enrichment analyses were performed and a comprehensive protein–protein interaction (PPI) network was constructed. Subsequently, the top ten hub genes selected by Cytoscape software were subjected to further analyses. It was illustrated that the expression level of CSF2, CTLA4, ETS1, PIK3CD, and CFTR was intimately associated with HNSCC. Survival analysis suggested that CTLA4 and FGFR2 could serve as effective independent prognostic biomarkers for HNSCC patients. Overall, our study lay a groundwork for further investigation into the underlying molecular mechanisms in HNSCC carcinogenesis, providing potential biomarkers and therapeutic targets for HNSCC.

Update on the role of emerging stem cell technology in head and neck medicine

Head and neck surgery is a broad discipline that involves the management of complex conditions such as burns, skin cancer, head and neck cancer, congenital abnormalities, and facial rejuvenation. For patients with cancer, surgery, radiotherapy, and chemotherapy are often the main modes of treatment. Many patients require follow-up reconstructive surgery, and the use of stem cells offers novel treatments that could aid recovery. Laryngeal, tracheal, and neuronal tissues are frequently damaged by surgery in the head and neck and these tissues have little intrinsic regenerative ability. Pluripotent embryonic stem cells retain the ability to differentiate into a wide variety of cells meaning that large tissue defects can be reduced by stimulating new cell growth. Research has demonstrated potential benefits of using stem cells in facial rejuvenation procedures and the management of burns sequelae. The advancements made in the use of adult progenitor stem cells as a possible source for pluripotent stem cells (induced pluripotent stem cells) mean that ethical considerations around the use of embryological tissue can be minimized, allowing for more research to take place. Currently, the evidence base for the use of stem cells in head and neck surgery is limited, but it has now been proven that stem cells can act as a source for lost or damaged tissue in the head and neck. With continuous advancements being made in the fields of tissue engineering, it is likely that stem cells will play a major role in head and neck surgery in the future.

Cutaneous Cancer Biology

There has been a drastic increase in the incidence of nonmelanoma (NMSC), including squamous, basal cell, and melanoma skin cancers worldwide. Most cases of skin cancer can be treated effectively with surgery; fewer than 10% of cases are advanced and may require additional therapies. A better understanding of the biology of skin cancer will help contribute to better prognostic information and identification of possible new therapeutic targets. Herein, the authors review the biology and pathogenesis of both NMSC and melanoma, focusing on critical cell signaling pathways mediating the disease and current therapeutic strategies targeted to underlying genetic pathways.

Biosafety evaluation of culture-expanded human chondrocytes with growth factor cocktail: a preclinical study

The scarcity of chondrocytes is a major challenge for cartilage tissue engineering. Monolayer expansion is necessary to amplify the limited number of chondrocytes needed for clinical application. Growth factors are often added to improve monolayer culture conditions, promoting proliferation, and enhancing chondrogenesis. Limited knowledge on the biosafety of the cell products manipulated with growth factors in culture has driven this study to evaluate the impact of growth factor cocktail supplements in chondrocyte culture medium on chondrocyte genetic stability and tumorigenicity. The growth factors were basic fibroblast growth factor (b-FGF), transforming growth factor β2 (TGF β2), insulin-like growth factor 1 (IGF-1), insulin-transferrin-selenium (ITS), and platelet-derived growth factor (PD-GF). Nasal septal chondrocytes cultured in growth factor cocktail exhibited a significantly high proliferative capacity. Comet assay revealed no significant DNA damage. Flow cytometry showed chondrocytes were mostly at G0-G1 phase, exhibiting normal cell cycle profile with no aneuploidy. We observed a decreased tumour suppressor genes’ expression (p53, p21, pRB) and no TP53 mutations or tumour formation after 6 months of implantation in nude mice. Our data suggest growth factor cocktail has a low risk of inducing genotoxic and tumorigenic effects on chondrocytes up to passage 6 with 16.6 population doublings. This preclinical tumorigenicity and genetic instability evaluation is crucial for further clinical works.

Discovery and optimization of novel pyrazole-benzimidazole CPL304110, as a potent and selective inhibitor of fibroblast growth factor receptors FGFR (1-3)

The FGFR family is characterized by four receptors (FGFR 1-4), binding to 18 ligands called fibroblast growth factors (FGFs). Aberrant activation of FGFs and their FGFRs has been implicated in a broad spectrum of human tumors. We employed the scaffolds hybridization approach, scaffold-hopping concept to synthesize a series of novel pyrazole-benzimidazole derivatives 56 (a-x). Compound 56q (CPL304110) was identified as a selective and potent pan-FGFR inhibitor for FGFR1, -2, -3 with IC₅₀s of 0.75 nM, 0.50 nM, 3.05 nM respectively, whereas IC₅₀ of 87.90 nM for FGFR4. Due to its favorable pharmacokinetic profile, low toxicity and potent anti-tumor activity in vivo, compound 56q is currently under evaluation in phase I clinical trial for the treatment of bladder, gastric and squamous cell lung cancers (01FGFR2018; NCT04149691).

New vistas in malignant mesothelioma: MicroRNA architecture and NRF2/MAPK signal transduction

Malignant mesothelioma (MM) is a cancer of the mesothelial lining of the pleura, peritoneum, pericardium and testes. The most common form is asbestos-linked MM that is etiologically linked to repeated asbestos exposure with a long latency period, although non-asbestos MM has also been reported. Late diagnosis, poor survival rates, lack of diagnostic and prognostic markers act as major impediments in the clinical management of MM. Despite advances in immune checkpoint inhibition and CAR T-cell-based therapies, MM which is of different histologic subtypes remains challenging to treat. We review microRNAs (miRNAs) and the miRNA interactome implicated in MM which can be useful as circulating miRNA biomarkers for early diagnosis of MM and as biomarkers for prognostication in MM. Further, we underscore the relevance of the NRF2/MAPK signal transduction pathway that has been implicated in MM which may be useful as druggable targets or as biomarkers of predictive response. In addition, since MM is driven partly by inflammation, we elucidate chemopreventive phytochemicals that are beneficial in MM, either via crosstalk with the NRF2/MAPK pathway or via concerted anticancer mechanisms, and may be of benefit as adjuvants in chemotherapy. Taken together, a multifactorial approach comprising identification of miRNA target hubs and NRF2/MAPK biomarkers along with appropriately designed clinical trials may enable early detection and faster intervention in MM translating into better patient outcomes for this aggressive cancer.

Hypoxia Induces Resistance to EGFR Inhibitors in Lung Cancer Cells via Upregulation of FGFR1 and the MAPK Pathway

Development of resistance remains the key obstacle to the clinical efficacy of EGFR tyrosine kinase inhibitors (TKI). Hypoxia is a key microenvironmental stress in solid tumors associated with acquired resistance to conventional therapy. Consistent with our previous studies, we show here that long-term, moderate hypoxia promotes resistance to the EGFR TKI osimertinib (AZD9291) in the non-small cell lung cancer (NSCLC) cell line H1975, which harbors two EGFR mutations including T790M. Hypoxia-induced resistance was associated with development of epithelial-mesenchymal transition (EMT) coordinated by increased expression of ZEB-1, an EMT activator. Hypoxia induced increased fibroblast growth factor receptor 1 (FGFR1) expression in NSCLC cell lines H1975, HCC827, and YLR086, and knockdown of FGFR1 attenuated hypoxia-induced EGFR TKI resistance in each line. Upregulated expression of FGFR1 by hypoxia was mediated through the MAPK pathway and attenuated induction of the proapoptotic factor BIM. Consistent with this, inhibition of FGFR1 function by the selective small-molecule inhibitor BGJ398 enhanced EGFR TKI sensitivity and promoted upregulation of BIM levels. Furthermore, inhibition of MEK activity by trametinib showed similar effects. In tumor xenografts in mice, treatment with either BGJ398 or trametinib enhanced response to AZD9291 and improved survival. These results suggest that hypoxia is a driving force for acquired resistance to EGFR TKIs through increased expression of FGFR1. The combination of EGFR TKI and FGFR1 or MEK inhibitors may offer an attractive therapeutic strategy for NSCLC. SIGNIFICANCE: Hypoxia-induced resistance to EGFR TKI is driven by overexpression of FGFR1 to sustain ERK signaling, where a subsequent combination of EGFR TKI with FGFR1 inhibitors or MEK inhibitors reverses this resistance. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/21/4655/F1.large.jpg.

Overexpression of sprouty 1 protein in human oral squamous cell carcinogenesis

Abstract Background/purpose

Sprouty (SPRY) has four isoforms, SPRY1–4, and its deficiency produces haphazard ‘sprouting’ of tracheal tubules. This study investigated SPRY1 protein expression in human oral potentially malignant disorders (OPMDs) and oral squamous cell carcinomas (OSCCs).

Materials and methods

90 OSCCs, 10 OPMDs with malignant transformation (MT), 17 OPMDs without MT, and six normal oral mucosa (NOM) tissue samples were subjected to immunohistochemical staining. Three human oral cancer cell lines (OCCLs), an oral precancer cell line (DOK), and a primary culture of normal oral keratinocytes (HOK) were used for western blotting.

Results

Significantly increased expression of SPRY1 protein from NOM and OPMD without MT to OSCC was observed. The protein expressions of SPRY1 in OCCLs were significantly enhanced as compared with DOK and HOK. Increased phosphor/total-ERK expression was observed in OCCLs as compared with HOK. A significantly increased SPRY1 protein level was noted in OPMDs with MT as compared with those without MT, in addition to a significant increase in DOK in comparison with HOK.

Conclusion

Our results indicated that overexpression of SPRY1 protein is potentially associated with human oral squamous cell carcinogenesis.

Fgf10/Fgfr2b Signaling in Mammary Gland Development, Homeostasis, and Cancer

Fibroblast growth factor 10 (Fgf10) is a secreted ligand acting via the Fibroblast growth factor receptor 2b (Fgfr2b). Fgf10/Fgfr2b signaling plays important roles both in the epithelium and in the mesenchyme during mammary gland development. Evidence in mice show that Fgf10 is critical for the induction of four out of five of the mammary placodes and for the formation of the white adipose tissue. Fgfr2b ligands also play important function in the maintenance of the terminal end buds, specialized structures at the tip of the ramified ducts during the postnatal phase of mammary gland development. Finally, in humans, FGF10 has been described to be expressed in 10% of the breast adenocarcinoma and activation of FGFR2b signaling correlates with a worse prognostic. Therefore, Fgf10 plays pleiotropic roles in both mammary gland development, homeostasis and cancer and elucidating its mechanism of action and cellular targets will be crucial to either enhance mammary gland development or to find innovative targets to treat aggressive breast cancer.

MicroRNA-107 Ameliorates Damage in a Cell Model of Alzheimer's Disease by Mediating the FGF7/FGFR2/PI3K/Akt Pathway

Alzheimer's disease (AD), the most prevalent representation of dementia, is a neurodegenerative disease resulting from the degenerative disturbance of the central nervous system. Previous studies have indicated that miR-107 is reduced in the brain neocortex of patients with AD; however, its underlying mechanism is not clear. Therefore, the objective of this study was to explore the question of whether miR-107 participates in AD development. The study confirmed that the miR-107 expression levels were dramatically decreased in patients with AD and in beta-amyloid (Aβ) (Aβ)-treated SH-SY5Y cells compared with control groups. Upregulation of miR-107 reversed the inhibitory role of Aβ on cell proliferation and viability. In addition, miR-107 upregulation also ameliorated the Aβ-induced inflammation and apoptosis of SH-SY5Y cells. Furthermore, using bioinformatic prediction, dual-luciferase reporter assay (DLRA), quantitative polymerase chain reaction (qPCR), and Western blot (WB), miR-107 was confirmed to reduce the expression level of FGF7, and it subsequently deactivated the FGFR2/PI3K/Akt pathway. Moreover, FGF7 overexpression counteracted the role of miR-107 in the viability, proliferation, inflammation, and apoptosis of Aβ-induced SH-SY5Y cells.

miR-187-3p increases gemcitabine sensitivity in breast cancer cells by targeting FGF9 expression

Breast cancer is the most common type of malignancy in women, which remains a significant health concern worldwide. Gemcitabine is a frequently applied anticancer pharmacological agent. However, the efficacy of gemcitabine is limited by chemoresistance. In the present study, a combination of reverse transcription quantitative-PCR, cell viability, flow cytometry, luciferase reporter assay and western blot analysis were performed to elucidate the potential effects of miR-187-3p on gemcitabine sensitivity in the breast cancer cell line, MDA-MB-231. The results revealed that miR-187-3p was significantly decreased in the breast cancer tumor tissues. Moreover, the overexpression of miR-187-3p significantly inhibited cell viability and promoted apoptosis in MDA-MB-231 cells. In addition, miR-187-3p overexpression enhanced the anti-proliferative and pro-apoptotic effects of gemcitabine, indicating that miR-187-3p regulated gemcitabine sensitivity in breast cancer cells. Mechanistically, miR-187-3p negatively regulated the expression of fibroblast growth factor 9 (FGF9) by binding to its 3'-untranslated region. Overexpression of FGF9 reversed the aforementioned effects of miR-187-3p overexpression on cell viability and apoptosis in the presence of gemcitabine. In conclusion, the present study indicated that miR-187-3p increased gemcitabine sensitivity in breast cancer cells by targeting FGF9 expression.

Role of extra cellular proteins in gastric cancer progression and metastasis: an update

Background

Gastric cancer (GC) is one of the most common cancers in the world with a high ratio of mortality. Regarding the late diagnosis, there is a high ratio of distant metastasis among GC cases. Despite the recent progresses in therapeutic modalities, there is not still an efficient therapeutic method to increase survival rate of metastatic GC cases.

Main body

Apart from the various intracellular signaling pathways which are involved in tumor cell migration and metastasis, the local microenvironment is also a critical regulator of tumor cell migration. Indeed, the intracellular signaling pathways also exert their final metastatic roles through regulation of extra cellular matrix (ECM). Therefore, it is required to assess the role of extra cellular components in biology of GC.

Conclusion

In the present review, we summarize 48 of the significant ECM components including 17 ECM modifying enzymes, seven extracellular angiogenic factors, 13 cell adhesion and cytoskeletal organizers, seven matricellular proteins and growth factors, and four proteoglycans and extra cellular glycoproteins. This review paves the way of determination of a specific extra cellular diagnostic and prognostic panel marker for the GC patients.

Molecular mechanism of acquired drug resistance in the EGFR-TKI resistant cell line HCC827-TR

Background

The first‐line standard treatment of non‐small cell lung cancer (NSCLC) with EGFR mutation is EGFR‐tyrosine kinase inhibitors (TKIs). However, most patients will develop acquired resistance after 9–13 months. This study investigated novel molecular mechanisms of acquired resistance to EGFR‐TKIs to identify a potential new treatment for EGFR‐TKI resistant NSCLC patients.

Methods

We established an EGFR‐TKI resistant cell line (HCC827‐TR) by culturing the HCC827‐P cell line through continuous erlotinib culture. We used Sanger sequencing, RT‐PCR, and western blot to rule out known resistance mechanisms in HCC827‐TR cells, including EGFR‐T790M and MET, PTEN, or EGFR expression changes. Next‐generation sequencing was performed and identified differentially expressed genes between two cell lines and examined the genes with GO and KEGG pathway database analyses. We also examined the molecular alterations in COSMIC and GDSC databases and performed hazard predictions using SIFT, PolyPhen‐2, Mutation Taster, and CADD.

Results

Our results identified FGF2 as a differentially expressed gene with a G101T point mutation in HCC827‐TR cells that showed high mutation frequency and hazard score. HCC827‐TR cells showed elevated FGF2 compared to parental cells. It is noteworthy that treatment with the FGFR inhibitor AZD4547 could restore the sensitivity of HCC872‐TR cells to erlotinib.

Conclusions

An erlotinib‐resistant cell line HCC827‐TR was successfully constructed and we identified the EGFR‐TKI resistance mechanism involving the FGF2 gene mutation. Targeted inhibition of the FGF2/FGFR signaling pathway may effectively restore the sensitivity of the resistant cells to erlotinib. These results suggest a novel treatment strategy for EGFR‐TKI resistant NSCLC patients.

Key points

Significant findings of the study: Identifies a novel molecular mechanism for EGFR‐TKI acquired resistance.

What this study adds: A potential novel strategy for the treatment of EGFR‐TKI resistant NSCLC patients.

The Integrated Analyses of Driver Genes Identify Key Biomarkers in Thyroid Cancer

AIM

Thyroid cancer is the most common endocrine cancer, the incidence rate has continuously increased worldwide. However, there are still lack of effective molecular biomarkers for the diagnosis and treatment of the disease. The study was conducted to identify driver genes that may serve as potential biomarkers for the disease.

METHODS

The computational tools oncodriveCLUST, oncodriveFM, icages and drgap were used to detect driver genes in thyroid cancer using somatic mutations from The Cancer Genome Atlas database. Integrated analyses were performed on the driver genes using multiomics data from the TCGA database.

RESULTS

A set of 291 driver genes were identified in thyroid cancer. BRAF, NRAS, HRAS, OTUD4, EIF1AX were the top 5 frequently mutated genes in thyroid cancer. The weighted gene co-expression network analysis identified 4 coexpression modules. The modules 1-3 were significantly associated with patients' tumor size, residual tumor, cancer stage, distant metastasis and multifocality. SEC24B, MET and ITGAL were the hub genes in the modules 1-3 respectively. Hierarchical clustering analysis of the 20 driver genes with the most frequent copy number changes revealed 3 clusters of PRAD patients. Cluster 1 tumors exhibited significantly older age, tumor size, cancer stages, and poorer prognosis than cluster 2 and 3 tumors. 16 genes were significantly associated with number of lymph nodes, tumor size and pathologic stage, such as IL7 R, IRS1, PTK2B, MAP3K3 and FGFR2.

CONCLUSIONS

The set of cancer genes and subgroups of patients shed insight on the tumorigenesis of thyroid cancer and open up avenues for developing prognostic biomarkers and driver gene-targeted therapies in thyroid cancer.

Molecular Signature of Subtypes of Non-Small-Cell Lung Cancer by Large-Scale Transcriptional Profiling: Identification of Key Modules and Genes by Weighted Gene Co-Expression Network Analysis (WGCNA)

Non-small-cell lung cancer (NSCLC) represents a heterogeneous group of malignancies consisting essentially of adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Although the diagnosis and treatment of ADC and SCC have been greatly improved in recent decades, there is still an urgent need to identify accurate transcriptome profile associated with the histological subtypes of NSCLC. The present study aims to identify the key dysregulated pathways and genes involved in the development of lung ADC and SCC and to relate them with the clinical traits. The transcriptional changes between tumour and normal lung tissues were investigated by RNA-seq. Gene ontology (GO), canonical pathways analysis with the prediction of upstream regulators, and weighted gene co-expression network analysis (WGCNA) to identify co-expressed modules and hub genes were used to explore the biological functions of the identified dysregulated genes. It was indicated that specific gene signatures differed significantly between ADC and SCC related to the distinct pathways. Of identified modules, four and two modules were the most related to clinical features in ADC and SCC, respectively. CTLA4, MZB1, NIP7, and BUB1B in ADC, as well as GNG11 and CCNB2 in SCC, are novel top hub genes in modules associated with tumour size, SUVmax, and recurrence-free survival. Our research provides a more effective understanding of the importance of biological pathways and the relationships between major genes in NSCLC in the perspective of searching for new molecular targets.

Prognostic and clinicopathological significance of FGFR1 gene amplification in resected esophageal squamous cell carcinoma: a meta-analysis

Background

Previous studies about the prognostic and clinicopathological significance of fibroblast growth factor receptor 1 (FGFR1) amplification in resected esophageal squamous cell carcinoma (ESCC) are controversial. Therefore, the aim of the current meta-analysis was to determine the association of FGFR1 amplification with prognosis and clinicopathological characteristics of resected ESCC patients.

Methods

The PubMed, EMBASE, Web of Science, The Cochrane Library, CNKI, Wanfang, VIP and SinoMed databases were searched systematically from the establishment date of databases to April 1, 2019 to identify related studies. The correlations of FGFR1 amplification of prognosis and clinicopathological characteristics in ESCC were assessed by the combined hazard ratio (HR) with 95% confidence interval (CI) and combined odds ratio (OR) with 95% CI, respectively. All statistical analyses were performed by the Stata 12.0 software.

Results

A total of nine retrospective studies involving 2,326 patients who received the surgery were included into the current meta-analysis. The results indicated that FGFR1 amplification was significantly correlated with worse overall survival (OS) (HR =1.50, 95% CI: 1.25-1.81, P<0.001), disease-free survival (DFS) (HR =1.58, 95% CI: 1.27-1.96, P<0.001), lymph node metastasis (OR =1.45, 95% CI: 1.13-1.86, P=0.004), higher TNM stage (OR =1.33, 95% CI: 1.03-1.72, P=0.027) and poorer differentiation (OR =1.10, 95% CI: 1.07-1.13, P<0.001).

Conclusions

The current meta-analysis strongly demonstrates that FGFR1 amplification is an independent prognostic risk factor for resected ESCC patients and more prevalent among patients with advanced tumor stage and poorer differentiation.