Characteristics and Prognosis of 8p11.23-Amplified Squamous Lung Carcinomas

BACKGROUND

Copy number alterations are common genetic lesions in cancer. In squamous non-small cell lung carcinomas, the most common copy-number-altered loci are at chromosomes 3q26-27 and 8p11.23. The genes that may be drivers in squamous lung cancers with 8p11.23 amplifications are unclear.

METHODS

Data pertaining to copy number alterations, mRNA expression and protein expression of genes located in the 8p11.23 amplified region were extracted from various sources including The Cancer Genome Atlas, the Human Protein Atlas and the Kaplan Meier Plotter. Genomic data were analyzed using the cBioportal platform. Survival analysis of cases with amplifications compared to nonamplified cases was performed using the Kaplan Meier Plotter platform.

RESULTS

The 8p11.23 locus is amplified in 11.5% to 17.7% of squamous lung carcinomas. The most frequently amplified genes include NSD3, FGFR1 and LETM2. Only some of the amplified genes present concomitant overexpression at the mRNA level. These include NSD3, PLPP5, DDHD2, LSM1 and ASH2L, while other genes display lower levels of correlation, and still, some genes in the locus show no mRNA overexpression compared with copy-neutral samples. The protein products of most locus genes are expressed in squamous lung cancers. No significant difference in overall survival in 8p11.23-amplified squamous cell lung cancers versus nonamplified cancers is observed. In addition, there is no adverse effect of mRNA overexpression for relapse-free survival of any of the amplified genes.

CONCLUSION

Several genes that are part of the commonly amplified locus 8p11.23 in squamous lung carcinomas are putative oncogenic candidates. A subset of genes of the centromeric part of the locus, which is amplified more commonly than the telomeric part, show high concomitant mRNA expression.

Chronic Voluntary Alcohol Consumption Alters Promoter Methylation and Expression of Fgf-2 and Fgfr1

Alcohol abuse accounts for 3.3 million deaths annually, rendering it a global health issue. Recently, fibroblast growth factor 2 (FGF-2) and its target, fibroblast growth factor receptor 1 (FGFR1), were discovered to positively regulate alcohol-drinking behaviors in mice. We tested whether alcohol intake and withdrawal alter DNA methylation of Fgf-2 and Fgfr1 and if there is a correlation regarding mRNA expression of these genes. Blood and brain tissues of mice receiving alcohol intermittently over a six-week period were analyzed using direct bisulfite sequencing and qRT-PCR analysis. Assessment of Fgf-2 and Fgfr1 promoter methylation revealed changes in the methylation of cytosines in the alcohol group compared with the control group. Moreover, we showed that the altered cytosines coincided with binding motives of several transcription factors. We also found that Fgf-2 and Fgfr1 gene expression was significantly decreased in alcohol-receiving mice compared with control littermates, and that this effect was specifically detected in the dorsomedial striatum, a brain region involved in the circuitry of the reward system. Overall, our data showed alcohol-induced alterations in both mRNA expression and methylation pattern of Fgf-2 and Fgfr1. Furthermore, these alterations showed a reward system regional specificity, therefore, resembling potential targets for future pharmacological interventions.

Mutations in FGFR1 were associated with growth traits in sheep (Ovis aries)

For its role in the mediation of myoblast proliferation, fibroblast growth factor receptor 1 (FGFR1) was considered a functional candidate gene for growth performance in Tibetan sheep. Via the polymerase chain reaction-restriction fragment length polymorphism (PCR-PFLP) approach, four single nucleotide polymorphisms (SNPs) including g.14752C > T (intron 1), g.45361A > G (intron 7), g.49400A > G (3'UTR region) and g.49587A > T (3'UTR region), were identified in 422 ewes. The association analysis demonstrated that individuals carrying the AA genotype of g.49400A > G had significantly greater withers height, length than those with GG genotype (p < 0.05). Individuals with genotype AA of g.49587A > T had significantly greater weight and chest circumference than those with genotype TT (p < 0.01). Additionally, the individuals with Hap1/1 diplotypes (CAAA-CAAA) were highly significantly associated with weight and chest circumference than Hap1/2 diplotypes (CAAA-CAAT) (p < 0.05). The quantitative real-time polymerase chain reaction (qPCR) analysis revealed that the FGFR1 was detectable expressed in muscle tissues within three different age stage. Remarkably higher mRNA expression was detected at fetal lamb stage as compared with adult ewes (p < 0.01). The outcome of this research confirmed that both g.49400A > G and g.49587A > T of FGFR1 were involved in growth-related traits, which may be considered to be genetic markers for improving the growth traits of Tibetan sheep.

FGFR1 is an important prognostic factor in oral leukoplakia and tongue squamous cell carcinoma

BACKGROUND

Fibroblast growth factor receptor 1 is a potential prognostic factor for tongue squamous cell carcinoma and is associated with oral epithelial dysplasia grade in oral leukoplakia.

METHODS

Thirty cases of tongue squamous cell carcinoma and 30 cases of oral leukoplakia were analyzed. Fibroblast growth factor receptor 1 and phosphorylated Akt protein expression were analyzed by immunohistochemistry and quantified using a digital algorithm. Fibroblast growth factor receptor 1 gene amplification was analyzed by fluorescent in situ hybridization in the tongue squamous cell carcinoma cases.

RESULTS

Clinical appearance and dysplasia grade were correlated with oral leukoplakia malignant transformation. Oral leukoplakia cases presenting high fibroblast growth factor receptor 1 expression showed a higher risk of malignant transformation (p = 0.016, HR: 7.3, 95% CI: 1.4-37.4). Phosphorylated Akt showed faint to no expression in oral leukoplakia, which did not correlate with dysplasia grade or malignant transformation. High expression of fibroblast growth factor receptor 1 and phosohorylated Akt were associated with poor overall survival and disease-free survival in tongue squamous cell carcinoma, although only fibroblast growth factor receptor 1 expression was significantly associated with poor overall survival (p = 0.024; HR: 4.9, 95% CI: 1.2-19.9). Cases presenting double fibroblast growth factor receptor 1/phosphorylated Akt overexpression (n = 8) showed markedly impaired overall survival (p = 0.020; HR: 6.4, 95% CI: 1.3-31.1) and disease-free survival (p = 0.001, HR: 13.0, 95% CI: 3.0-55.7). Fibroblast growth factor receptor 1 amplification was observed in 16.6% of tongue squamous cell carcinoma cases, being correlated with vascular and neural invasion (p = 0.001 and 0.017, respectively), but not with fibroblast growth factor receptor 1 protein expression, overall survival, or disease-free survival.

CONCLUSION

Fibroblast growth factor receptor 1 protein expression is an important prognostic factor in oral leukoplakia and tongue squamous cell carcinoma.

Molecular Mechanisms Involved in Craniosynostosis

Craniosynostosis refers to the early fusion of one or many cranial sutures, causing craniofacial abnormalities observed in 1:2,500 births worldwide. In most cases (85%), craniosynostosis is presented as sporadic anomaly (non-syndromic craniosynostosis), while in other cases (15%) as part of syndromes (syndromic craniosynostosis). Patients with syndromic disorder usually have more severe symptoms compared to those with single suture synostosis. Most common syndromes of craniosynostosis include Pfeiffer, Apert, Crouzon, Jackson-Weiss, Muenke and Boston type MSX2-related syndrome. The main gene mutations in craniosynostosis involve FGFR1, FGFR2, FGFR3, TWIST1 and MSX2, which encode key factors influencing cranial bone morphogenesis. The main therapeutic approaches are surgical as discussed in this review, and the type of therapy depends on the graveness of the incident.

Non-small cell lung carcinomas with diffuse coexpression of TTF1 and p40: clinicopathological and genomic features of 14 rare biphenotypic tumours

Thyroid transcription factor 1 (TTF1) and p40 are widely-utilized diagnostic markers of lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC), respectively. Diffuse coexpression of TTF1 and p40 has been described in only rare case reports. In a multi-institutional study, we collected the largest cohort of these unusual tumours to-date (n = 14), with the goal of elucidating their clinicopathological and genomic characteristics. Lung tumours with diffuse coexpression (labelling 50-100% tumour cells) of TTF1 clone 8G7G3/1 and p40 clone BC28 were identified. Detailed clinicopathological and immunohistochemical parameters were analyzed. Eight tumours were analyzed by next-generation sequencing (NGS) and the results were compared to those in > 9 K LUAD and > 1 K LUSC. All tumours with diffuse TTF1/p40 coexpression were poorly differentiated non-small cell lung carcinomas (NSCLC), 42% of which had basaloid features. Some tumours exhibited focal keratinization (14%), napsin A and/or mucicarmine labelling (46%) or both squamous and glandular features (7%). NGS revealed a uniquely high rate of FGFR1 amplifications (70%) compared to either LUAD (0.7%, P < 0.0001) or LUSC (11%, P = 0.001). LUAD-type targetable driver alterations were identified in 38% of cases (one EGFR, two KRAS G12C). The tumours were clinically aggressive, exhibiting metastatic disease in most patients. Lung carcinomas with diffuse TTF1/p40 coexpression represent poorly differentiated NSCLCs with frequent basaloid features, but some show evidence of focal squamous, glandular or dual differentiation with a distinctly high rate of FGFR1 amplifications. The presence of targetable LUAD-type alterations (EGFR, KRAS G12C) emphasizes the importance of molecular testing in these tumours.

The FGFR1 Signaling Pathway Upregulates the Oncogenic Transcription Factor FOXQ1 to Promote Breast Cancer Cell Growth

FGFR1 is a receptor tyrosine kinase deregulated in certain breast cancers (BCs) with a poor prognosis. Although FGFR1-activated phosphorylation cascades have been mapped, the key genes regulated by FGFR1 in BC are largely unclear. FOXQ1 is an oncogenic transcription factor. Although we found that activation of FGFR1 robustly upregulated FOXQ1 mRNA, how FGFR1 regulates FOXQ1 gene expression and whether FOXQ1 is essential for FGFR1-stimulated cell proliferation are unknown. Herein, we confirmed that activation of FGFR1 robustly upregulated FOXQ1 mRNA and protein in BC cells. Knockdown of FOXQ1 blocked the FGFR1 signaling-stimulated BC cell proliferation, colony formation, and xenograft tumor growth. Inhibition of MEK or ERK1/2 activities, or knockout of ERK2 but not ERK1 suppressed the FGFR1 signaling-promoted FOXQ1 gene expression. Inhibition of ERK2 in ERK1 knockout cells blocked, while ectopic expression of FOXQ1 in ERK2 knockout cells rescued the FGFR1-signaling-promoted cell growth. Mechanistically, c-FOS, an early response transcription factor upregulated by the FGFR1-MEK-ERK2 pathway, bound to the FOXQ1 promoter to mediate the FGFR1 signaling-promoted FOXQ1 expression. These results indicate that the FGFR1-ERK2-c-FOS-FOXQ1 regulatory axis plays an essential role in the FGFR1 signaling-promoted BC growth. Targeting ERK2 and FOXQ1 should block BC growth caused by a deregulated FGFR1 signaling.

Inhibition of Cancer Cell Proliferation and Bacterial Growth by Silver(I) Complexes Bearing a CH3-Substituted Thiadiazole-Based Thioamide

Ag(I) coordination compounds have recently attracted much attention as antiproliferative and antibacterial agents against a wide range of cancer cell lines and pathogens. The bioactivity potential of these complexes depends on their structural characteristics and the nature of their ligands. Herein, we present a series of four Ag(I) coordination compounds bearing as ligands the CH₃-substituted thiadiazole-based thioamide 5-methyl-1,3,4-thiadiazole-2-thiol (mtdztH) and phosphines, i.e., [AgCl(mtdztH)(PPh₃)₂] (1), [Ag(mtdzt)(PPh₃)₃] (2), [AgCl(mtdztH)(xantphos)] (3), and [AgmtdztH)(dppe)(NO₃)]_n (4), where xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene and dppe = 1,2-bis(diphenylphosphino)ethane, and the assessment of their in vitro antibacterial and anti-cancer efficiency. Among them, diphosphine-containing compounds 3 and 4 were found to exhibit broad-spectrum antibacterial activity characteristics against both Gram-(+) and Gram-(-) bacterial strains, showing high in vitro bioactivity with IC₅₀ values as low as 4.6 μΜ. In vitro cytotoxicity studies against human ovarian, pancreatic, lung, and prostate cancer cell lines revealed the strong cytotoxic potential of 2 and 4, with IC₅₀ values in the range of 3.1-24.0 μΜ, while 3 and 4 maintained the normal fibroblast cells' viability at relatively higher levels. Assessment of these results, in combination with those obtained for analogous Ag(I) complexes bearing similar heterocyclic thioamides, suggest the pivotal role of the substituent groups of the thioamide heterocyclic ring in the antibacterial and anti-cancer efficacy of the respective Ag(I) complexes. Compounds 1-4 exhibited moderate in vitro antioxidant capacity for free radicals scavenging, as well as reasonably strong ability to interact with calf-thymus DNA, suggesting the likely implication of these properties in their bioactivity mechanisms. Complementary insights into the possible mechanism of their anti-cancer activity were provided by molecular docking calculations, exploring their ability to bind to the overexpressed fibroblast growth factor receptor 1 (FGFR1), affecting cancer cells' functionalities.

Infiltrating gliomas with FGFR alterations: Histologic features, genetic alterations, and potential clinical implications

BACKGROUND

Fibroblast growth factor receptors (FGFRs) are frequently altered in cancers and present a potential therapeutic avenue. However, the type and prevalence of FGFR alterations in infiltrating gliomas (IGs) needs further investigation.

OBJECTIVE

To understand the prevalence/type of FGFR alterations in IGs.

METHODS

We reviewed clinicopathologic and genomic alterations of FGFR-mutant gliomas in a cohort of 387 patients. Tumors were examined by DNA next-generation sequencing for somatic mutations with a panel interrogating 205-genes. For comparison, cBioPortal databases were queried to identify FGFR-altered IGs.

RESULTS

Fourteen patients (3.6%) with FGFR-mutant tumors were identified including 11 glioblastomas, Isocitrate dehydrogenase (IDH) - wildtype (GBM-IDH-WT), 2 oligodendrogliomas, and 1 astrocytoma IDH-mutant. FGFR-altered IGs showed endocrinoid capillaries, microvascular proliferation, necrosis, oligodendroglioma-like cells, fibrin thrombi, microcalcifications, and nodular growth. FGFR3 was the most commonly altered FGFR gene (64.3%). The most common additional mutations in FGFR-altered IGs were TERTp, CDKN2A/B, PTEN, CDK4, MDM2, and TP53. FGFR3 alterations were only observed in GBM-IDH-WT. EGFR alterations were rarely identified in FGFR3-altered gliomas.

CONCLUSIONS

Histologic features correlate with FGFR alterations in IGs. FGFR3-TACC3 fusion and FGFR3 amplification are the most common FGFR alterations in IGs. FGFR alterations are a rare, but potentially viable, therapeutic target in asubset of IGs.

Fibrosis-Associated Signaling Molecules Are Differentially Expressed in Palmar Connective Tissues of Patients with Carpal Tunnel Syndrome and Dupuytren's Disease

Carpal tunnel syndrome (CTS) and Dupuytren's disease (DD) are fibrotic conditions that affect the connective tissue of the hand and limit its functionality. The exact molecular mechanism underlying the fibrosis is unknown, and only some profibrotic factors have been investigated. In this cross-sectional study, we analyzed the expression of FGF signaling pathway molecules associated with fibrotic changes in the palmar fascia and the flexor retinaculum of 15 CTS patients and both clinically affected and unaffected palmar fascia of 15 DD patients, using immunofluorescence techniques. The expression of FGFR1, FGFR2, and CTGF in the blood vessel walls and surrounding connective tissue cells differed significantly between the analyzed groups, with changes in expression present even in clinically unremarkable tissues from DD patients. We also found altered expression of the analyzed factors, as well as TGF-β1 and syndecan-1 in DD-associated sweat glands, possibly implicating their role in the pathophysiology of the disease. The increased expression of profibrotic factors in the clinically unaffected palmar fascia of DD patients may indicate that more extensive excision is needed during surgical treatment, while the profibrotic factors could be potential targets for developing pharmacological therapeutic strategies against DD-associated fibrosis.

Aberrations in FGFR1, FGFR2, and RIP5 Expression in Human Congenital Anomalies of the Kidney and Urinary Tract (CAKUT)

This study aimed to explore the spatio-temporal expression patterns of congenital anomalies of kidney and urinary tract (CAKUT) candidate genes, Fibroblast Growth Factor Receptor 1 (FGFR1), Fibroblast Growth Factor Receptor 2 (FGFR2) and Receptor-Interacting Protein Kinase 5 (RIP5), in human fetal kidney development (CTRL) and kidneys affected with CAKUT. Human fetal kidneys from the 22nd to 41st developmental week (duplex, hypoplastic, dysplastic, and controls) were stained with antibodies and analyzed by epifluorescence microscopy and RT-qPCR. The effect of CAKUT candidate genes on kidney nephrogenesis and function is confirmed by statistically significant variations in the spatio-temporal expression patterns of the investigated markers. The nuclear localization of FGFR1, elevated expression score of FGFR1 mRNA, the increased area percentage of FGFR1-positive cells in the kidney cortex, and the overall decrease in the expression after the peak at the 27th developmental week in dysplastic kidneys (DYS), suggest an altered expression pattern and protein function in response to CAKUT pathophysiology. The RT-qPCR analysis revealed a significantly higher FGFR2 mRNA expression score in the CAKUT kidneys compared to the CTRL. This increase could be due to the repair mechanism involving the downstream mediator, Extracellular Signal-Regulated Kinase 1/2 (ERK1/2). The expression of RIP5 during normal human kidney development was reduced temporarily, due to urine production and increased later since it undertakes additional functions in the maturation of the postnatal kidney and homeostasis, while the expression dynamics in CAKUT-affected kidneys exhibited a decrease in the percentage of RIP5-positive cells during the investigated developmental period. Our findings highlight the importance of FGFR1, FGFR2, and RIP5 as markers in normal and pathological kidney development.

Circ_SNX27 regulates hepatocellular carcinoma development via miR-637/FGFR1 axis

BACKGROUND

Circular RNAs (circRNAs) serve as critical regulatory factors in cancer development. Nonetheless, the potential regulatory mechanism of circRNA sorting nexin 27 (circ_SNX27) in hepatocellular carcinoma (HCC) is still unknown.

METHODS

The circ_SNX27, microRNA-637 (miR-637), and fibroblast growth factor receptor 1 (FGFR1) levels were quantified by quantitative real-time polymerase chain reaction and western blot analysis. Next, function experiments were conducted using in vitro assays and in vivo senograft study. The relationship between miR-637 with circ_SNX27 or FGFR1 was uncovered by dual-luciferase reporter and RNA pull-down assays.

RESULTS

The circ_SNX27 and FGFR1 levels were up-regulated, but miR-637 content was reduced in HCC. Circ_SNX27 down-regulation inhibited HCC cell proliferation, motility, and invasion and promoted apoptosis in vitro, as well as weakened tumor growth in vivo. Circ_SNX27 served as a sponge of miR-637 to promote FGFR1 expression. MiR-637 reduction abolished the restrained effect of circ_SNX27 absence on HCC cell development. Moreover, miR-637 curbed HCC cell malignant phenotype by regulating FGFR1.

CONCLUSION

Circ_SNX27 contributed to HCC development via miR-637/FGFR1 axis, offering a new idea for the treatment of HCC.

Identification and function analysis of two fibroblast growth factor receptor (FGFR) from Scylla paramamosain: The evidence of FGFR involved in innate immunity in crustacean

The fibroblast growth factor receptor (FGFR) belongs to the tyrosine kinase family consisting of four members (FGFR1-4). This study involved identification and characterization of FGFR1 and FGFR3 from mud crab Scylla paramamosain for the first time. The obtained cDNAs of SpFGFR1 and SpFGFR3 were 2,380 bp and 2,982 bp in length with a 1,503 bp and 2,310 bp open reading frame, respectively. The predicted SpFGFR1 protein included three immunoglobulin domains and a transmembrane region, while SpFGFR3 protein possessed a typical TyrKc (Tyrosine kinase, catalytic) domain. Real-time PCR analysis showed that SpFGFR1 and SpFGFR3 were highly expressed in the hepatopancreas. Furthermore, the expression levels of SpFGFR1 and SpFGFR3 in the hepatopancreas were enhanced following challenges with Vibro alginolyticus, Staphylococcus aureus, Poly (I:C) and White spot syndrome virus, which shows the involvement of SpFGFR1 and SpFGFR3 in innate immune response to infections from bacteria and virus. There was significant suppression of six antimicrobial peptide genes (SpALF1-5 and SpCrustin) and three NF-κB members (SpDorsal, SpIKK and SpRelish) when SpFGFR1 and SpFGFR3 was interfered in vivo. Also, treatment of the hemocytes with specific inhibitor of SpFGFR for 24 h consistently down-regulated SpDorsal, SpRelish and AMPs. These results suggested that SpFGFR1 and SpFGFR3 played important roles in regulating the Toll signaling pathway and immune deficiency (IMD) pathway through NF-κB signaling pathway. These findings may provide new insights into the role of FGFRs in the innate immune function of crustaceans.

Deficiency of endothelial FGFR1 alleviates hyperoxia-induced bronchopulmonary dysplasia in neonatal mice

Disrupted neonatal lung angiogenesis and alveologenesis often give rise to bronchopulmonary dysplasia (BPD), the most common chronic lung disease in children. Hyperoxia-induced pulmonary vascular and alveolar damage in premature infants is one of the most common and frequent factors contributing to BPD. The purpose of the present study was to explore the key molecules and the underlying mechanisms in hyperoxia-induced lung injury in neonatal mice and to provide a new strategy for the treatment of BPD. In this work, we reported that hyperoxia decreased the proportion of endothelial cells (ECs) in the lungs of neonatal mice. In hyperoxic lung ECs of neonatal mice, we detected upregulated fibroblast growth factor receptor 1 (FGFR1) expression, accompanied by upregulation of the classic downstream signaling pathway of activated FGFR1, including the ERK/MAPK signaling pathway and PI3K-Akt signaling pathway. Specific deletion of Fgfr1 in the ECs of neonatal mice protected the lungs from hyperoxia-induced lung injury, with improved angiogenesis, alveologenesis and respiratory metrics. Intriguingly, the increased Fgfr1 expression was mainly attributed to aerosol capillary endothelial (aCap) cells rather than general capillary endothelial (gCap) cells. Deletion of endothelial Fgfr1 increased the expression of gCap cell markers but decreased the expression of aCap cell markers. Additionally, inhibition of FGFR1 by an FGFR1 inhibitor improved alveologenesis and respiratory metrics. In summary, this study suggests that in neonatal mice, hyperoxia increases the expression of endothelial FGFR1 in lung ECs and that deficiency of endothelial Fgfr1 can ameliorate hyperoxia-induced BPD. These data suggest that FGFR1 may be a potential therapeutic target for BPD, which will provide a new strategy for the prevention and treatment of BPD.

Research on the variants of FGFR1 and CEP290 genes in idiopathic hypogonadotropin hypogonadism

Idiopathic hypogonadotropic hypogonadism (IHH) is a rare endocrine disease characterized by gonadal dysplasia. According to whether the sense of smell is affected, this disorder is classified into Kallmann syndrome (KS) and normosmic isolated hypogonadotropic hypogonadism (nIHH). In this study, we reported a case of nIHH patient and explored the pathogenic mechanism of FGFR1 in nIHH. A FGFR1 variant (c.2008G>A, p.E670K) and a CEP290 variant (c.964G>A, p.D322N) were detected by the whole exome sequencing in this nIHH patient. Bioinformatic analysis revealed that this FGFR1 variant (c.2008G>A) causes structural perturbations in TK2 domain demonstrating that this variant result in FGFR1 loss-of-function and abnormal signaling. The identification of an additional CEP290 variant (c.964G>A) indicated that CEP290 might play a potential role in developmental abnormalities and inhibition of GnRH neuron release. A protein interaction network analysis showed that CEP290 was predicted to interact with FGFR1. In summary, our study identified the potential pathogenic mechanism(s) of the novel FGFR1 variant and indicated that CEP290 might play a role in the GnRH neuron migration route. Our findings expand the mutation spectrum of FGFR1 and CEP290 and provide a reference for clinical diagnosis and treatment of IHH.

The genomic landscape of dysembryoplastic neuroepithelial tumours and a comprehensive analysis of recurrent cases

AIMS

Dysembryoplastic neuroepithelial tumour (DNT) is a glioneuronal tumour that is challenging to diagnose, with a wide spectrum of histological features. Three histopathological patterns have been described: specific DNTs (both the simple form and the complex form) comprising the specific glioneuronal element, and also the non-specific/diffuse form which lacks it, and has unclear phenotype-genotype correlations with numerous differential diagnoses.

METHODS

We used targeted methods (immunohistochemistry, fluorescence in situ hybridisation and targeted sequencing) and large-scale genomic methodologies including DNA methylation profiling to perform an integrative analysis to better characterise a large retrospective cohort of 82 DNTs, enriched for tumours that showed progression on imaging.

RESULTS

We confirmed that specific DNTs are characterised by a single driver event with a high frequency of FGFR1 variants. However, a subset of DNA methylation-confirmed DNTs harbour alternative genomic alterations to FGFR1 duplication/mutation. We also demonstrated that a subset of DNTs sharing the same FGFR1 alterations can show in situ progression. In contrast to the specific forms, "non-specific/diffuse DNTs" corresponded to a heterogeneous molecular group encompassing diverse, newly-described, molecularly distinct entities.

CONCLUSIONS

Specific DNT is a homogeneous group of tumours sharing characteristics of paediatric low-grade gliomas: a quiet genome with a recurrent genomic alteration in the RAS-MAPK signalling pathway, a distinct DNA methylation profile and a good prognosis but showing progression in some cases. The "non-specific/diffuse DNTs" subgroup encompasses various recently described histomolecular entities, such as PLNTY and diffuse astrocytoma, MYB or MYBL1 altered.

TNFAIP3 promotes ALDH-positive breast cancer stem cells through FGFR1/MEK/ERK pathway

Breast cancer stem cells (BCSCs) are a tiny population of self-renewing cells that may contribute to cancer initiation, progression, and resistance to therapy in patients. In our prior study, we found that tumor necrosis factor alpha-induced protein 3 (TNFAIP3) is necessary for fibroblast growth factors receptor 1 (FGFR1) signaling-promoted tumor growth and progression in breast cancer (BC). This study aims to investigate the involvement of TNFAIP3 in regulating BCSCs. In this work, we showed that ALDH-positive BCSCs were increased by activating the FGFR1-MEK-ERK pathway, meanwhile utilizing FGFR1 inhibitor, MEK inhibitor, or ERK inhibitor reversed the phenomenon in BC cells. Moreover, ALDH-positive BCSCs were decreased in TNFAIP3-knockout or TNFAIP3-depressing cells. In vivo analysis displayed that TNFAIP3-silenced MDA-MB-231 xenografts developed smaller tumors and ALDH immunostaining levels were significantly lower in TNFAIP3-depressing or TNFAIP3-knockout tumor tissues. Besides, our results also revealed that TNFAIP3 influences the transcription stemness factors gene expression. Taken together, TNFAIP3 could be a potential regulator in FGFR1-MEK-ERK-promoted ALDH-positive BCSCs.

TTYH3 Modulates Bladder Cancer Proliferation and Metastasis via FGFR1/H-Ras/A-Raf/MEK/ERK Pathway

Tweety family member 3 (TTYH3) is a calcium-activated chloride channel with a non-pore-forming structure that controls cell volume and signal transduction. We investigated the role of TTYH3 as a cancer-promoting factor in bladder cancer. The mRNA expression of TTYH3 in bladder cancer patients was investigated using various bioinformatics databases. The results demonstrated that the increasingly greater expression of TTYH3 increasingly worsened the prognosis of patients with bladder cancer. TTYH3 knockdown bladder cancer cell lines were constructed by their various cancer properties measured. TTYH3 knockdown significantly reduced cell proliferation and sphere formation. Cell migration and invasion were also significantly reduced in knockdown bladder cancer cells, compared to normal bladder cancer cells. The knockdown of TTYH3 led to the downregulation of H-Ras/A-Raf/MEK/ERK signaling by inhibiting fibroblast growth factor receptor 1 (FGFR1) phosphorylation. This signaling pathway also attenuated the expression of c-Jun and c-Fos. The findings implicate TTYH3 as a potential factor regulating the properties of bladder cancer and as a therapeutic target.

FGFR1-4 RNA-Based Gene Alteration and Expression Analysis in Squamous Non-Small Cell Lung Cancer

While fibroblast growth factor receptors (FGFRs) are involved in several biological pathways and FGFR inhibitors may be useful in the treatment of squamous non-small cell lung cancer (Sq-NSCLC), FGFR aberrations are not well characterized in Sq-NSCLC. We comprehensively evaluated FGFR expression, fusions, and variants in 40 fresh-frozen primary Sq-NSCLC (stage IA3−IV) samples and tumor-adjacent normal tissues using real-time PCR and next-generation sequencing (NGS). Protein expression of FGFR1−3 and amplification of FGFR1 were also analyzed. FGFR1 and FGFR4 median gene expression was significantly (p < 0.001) decreased in tumors compared with normal tissue. Increased FGFR3 expression enhanced the recurrence risk (hazard ratio 4.72, p = 0.029), while high FGFR4 expression was associated with lymph node metastasis (p = 0.036). Enhanced FGFR1 gene expression was correlated with FGFR1 protein overexpression (r = 0.75, p = 0.0003), but not with FGFR1 amplification. NGS revealed known pathogenic FGFR2,3 variants, an FGFR3::TACC3 fusion, and a novel TACC1::FGFR1 fusion together with FGFR1,2 variants of uncertain significance not previously reported in Sq-NSCLC. These findings expand our knowledge of the Sq-NSCLC molecular background and show that combining different methods increases the rate of FGFR aberrations detection, which may improve patient selection for FGFRi treatment.

SOHO State of the Art Updates and Next Questions | Myeloid/Lymphoid Neoplasms with Eosinophilia and Gene Rearrangements: Diagnostic Pearls and Pitfalls

The myeloid and/or lymphoid neoplasms with eosinophilia and gene rearrangement (MLN-Eos) are a rare group of hematopoietic neoplasms with diverse and often perplexing presentations that can cause challenges, and even potential pitfalls, for the diagnostic pathologist. However, accurate diagnosis of this group of disorders is of the utmost importance, since the presence of specific gene rearrangements dictates targeted patient therapy. The goal of this review is to discuss the current literature, including emergence of novel molecular data, and equip pathologists and clinicians with morphologic and immunophenotypic clues for diagnosing this challenging group of hematopoietic neoplasms.

TNFAIP3 mediates FGFR1 activation-induced breast cancer angiogenesis by promoting VEGFA expression and secretion

PURPOSE

To investigate the role and mechanism of TNF-inducible protein 3(TNFAIP3) in breast cancer angiogenesis induced by fibroblast growth factor receptor1 (FGFR1) activation.

METHODS

The immunohistochemical assay was used to detect the expression of vascular endothelial cell marker CD31 and CD105 in mice DCIS.COM-iFGFR1 transplanted tumor (previously established by our group). The effects of TNFAIP3 knockout/knockdown breast cancer cell lines on angiogenesis, migration, and invasion of Human Umbilical Vein Endothelial Cells (HUVEC) were detected by the tubulogenesis and Trewells assay. RNA-seq analysis of TNFAIP3 downstreams differential genes after TNFAIP3 knockdown. The expression and secretion of VEGFA after FGFR1 activation in breast cancer cells were detected by qPCR, Western blot, and ELISA.

RESULTS

Immunohistochemistry showed that TNFAIP3 knockout inhibited the expression of CD31 and CD105 in DCIS grafted tumors promoted by FGFR1 activation. Tubulogenesis and Trewells experiments showed that TNFAIP3 gene knockout/knockdown inhibited the angiogenesis, migration, and invasion of HUVEC cells promoted by FGFR1 activation. qPCR assay showed that VEGFA mRNA level in the TNFAIP3 knockdown cell line was significantly down-regulated (p < 0.05). qPCR, Western blot and ELISA results showed that TNFAIP3 gene knockout/knockdown could inhibit the expression and secretion of VEGFA in breast cancer cells induced by FGFR1 activation.

CONCLUSION

TNFAIP3 promotes breast cancer angiogenesis induced by FGFR1 activation through the expression and secretion of VEGFA.

Immune Microenvironment and Lineage Tracing Help to Decipher Rosette-Forming Glioneuronal Tumors: A Multi-Omics Analysis

Rosette-forming glioneuronal tumors (RGNT) are rare low-grade primary central nervous system (CNS) tumors. The methylation class (MC) RGNT (MC-RGNT) delineates RGNT from other neurocytic CNS tumors with similar histological features. We performed a comprehensive molecular analysis including whole-exome sequencing, RNAseq, and methylome on 9 tumors with similar histology, focusing on the immune microenvironment and cell of origin of RGNT. Three RGNT in this cohort were plotted within the MC-RGNT and characterized by FGFR1 mutation plus PIK3CA or NF1 mutations. RNAseq analysis, validated by immunohistochemistry, identified 2 transcriptomic groups with distinct immune microenvironments. The "cold" group was distinguishable by a low immune infiltration and included the 3 MC-RGNT and 1 MC-pilocytic astrocytoma; the "hot" group included other tumors with a rich immune infiltration. Gene set enrichment analysis showed that the "cold" group had upregulated NOTCH pathway and mainly oligodendrocyte precursor cell and neuronal phenotypes, while the "hot" group exhibited predominantly astrocytic and neural stem cell phenotypes. In silico deconvolution identified the cerebellar granule cell lineage as a putative cell of origin of RGNT. Our study identified distinct tumor biology and immune microenvironments as key features relevant to the pathogenesis and management of RGNT.

A truncated derivative of FGFR1 kinase cooperates with FLT3 and KIT to transform hematopoietic stem cells in syndromic and de novo AML

Background

Myeloid and lymphoid malignancies associated with chimeric FGFR1 kinases are the hallmark of stem cell leukemia and lymphoma syndrome (SCLL). In all cases, FGFR1 kinase is constitutively phosphoactivated as a result of chromosome translocations, which lead to acquisition of dimerization motifs in the chimeric proteins. Recently, we demonstrated that these chimeric kinases could be cleaved by granzyme B to generate a truncated derivative, tnFGFR1, which localized exclusively into the nucleus and was not phosphorylated.

Methods

Stem cell transduction and transplantation in syngeneic mice was used to assess the transforming ability of tnFGFR1 in bone marrow stem cells, and RPPA and RNA-Seq was used to examine the related signaling pathways and regulated target genes.

Results

For the first time, we show that this non-classical truncated form of FGFR1 can independently lead to oncogenic transformation of hematopoietic stem cells in an animal model in vivo. These leukemia cells show a mixed immunophenotype with a B-cell B220 + Igm- profile in the majority of cells and Kit+ in virtually all cells, suggesting a stem cell disease. tnFGFR1, however, does not activate classic FGFR1 downstream signaling pathways but induces a distinct profile of altered gene expression with significant upregulation of transmembrane signaling receptors including FLT3 and KIT. We further show that de novo human AML also express tnFGFR1 which correlates with upregulation of FLT3 and KIT as in mouse leukemia cells. ChIP analysis demonstrates tnFGFR1 occupancy at the Flt3 and Kit promoters, suggesting a direct transcriptional regulation. Cells transformed with tnFGFR1 are insensitive to FGFR1 inhibitors but treatment of these cells with the Quizartinib (AC220) FLT3 inhibitor, suppresses in vitro growth and development of leukemia in vivo. Combined treatment with FGFR1 and FLT3 inhibitors provides increased survival compared to FGFR1 inhibition alone.

Conclusions

This study demonstrates a novel model for transformation of hematopoietic stem cells by chimeric FGFR1 kinases with the combined effects of direct protein activation by the full-length kinases and transcriptional regulation by the truncated nuclear tnFGFR1 derivative, which is associated with GZMB expression levels. Genes significantly upregulated by tnFGFR1 include Flt3 and Kit which promote a leukemia stem cell phenotype. In human AML, tnFGFR1 activation leads to increased FLT3 and KIT expression, and higher FLT3 and GZMB expression levels are associated with an inferior prognosis. These observations provide insights into the relative therapeutic value of targeting FGFR1 and FLT3 in treating AML with this characteristic gene expression profile.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-022-01628-3.

Prediction of Response to Cisplatin-Based Neoadjuvant Chemotherapy of Muscle-Invasive Bladder Cancer Patients by Molecular Subtyping including KRT and FGFR Target Gene Assessment

Patients with muscle-invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NAC) have improved prognosis. Molecular subtypes of bladder cancer differ markedly regarding sensitivity to cisplatin-based chemotherapy and harbor FGFR treatment targets to various content. The objective of the present study was to evaluate whether preoperative assessment of molecular subtype as well as FGFR target gene expression is predictive for therapeutic outcome—rate of ypT0 status—to justify subsequent prospective validation within the “BladderBRIDGister”. Formalin-fixed paraffin-embedded (FFPE) tissue specimens from transurethral bladder tumor resections (TUR) prior to neoadjuvant chemotherapy and corresponding radical cystectomy samples after chemotherapy of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, Relative gene expression of subtyping markers (e.g., KRT5, KRT20) and target genes (FGFR1, FGFR3) was analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, Kruskal−Wallis, Mann−Whitney and sensitivity/specificity tests were performed by JMP 9.0.0 (SAS software). The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being node-negative during radical cystectomy after 1 to 4 cycles of NAC. When comparing pretreatment with post-treatment samples, the median expression of KRT20 dropped most significantly from DCT 37.38 to 30.65, which compares with a 128-fold decrease. The reduction in gene expression was modest for other luminal marker genes (GATA3 6.8-fold, ERBB2 6.3-fold). In contrast, FGFR1 mRNA expression increased from 33.28 to 35.88 (~6.8-fold increase). Spearman correlation revealed positive association of pretreatment KRT20 mRNA levels with achieving pCR (r = 0.3072: p = 0.0684), whereas pretreatment FGFR1 mRNA was associated with resistance to chemotherapy (r = −0.6418: p < 0.0001). Hierarchical clustering identified luminal tumors of high KRT20 mRNA expression being associated with high pCR rate (10/16; 63%), while the double-negative subgroup with high FGFR1 expression did not respond with pCR (0/9; 0%). Molecular subtyping distinguishes patients with high probability of response from tumors as resistant to neoadjuvant chemotherapy. Targeting FGFR1 in less-differentiated bladder cancer subgroups may sensitize tumors for adopted treatments or subsequent chemotherapy.

FGFR1 promotes tumor immune evasion via YAP-mediated PD-L1 expression upregulation in lung squamous cell carcinoma

BACKGROUND

Variations in FGFR1 are common driver mutations of LSQCC. And immune checkpoint inhibitors targeting PD-1 and PD-L1 are powerful anticancer weapons. Activation of FGFR1 leads to tumorigenesis through multiple downstream molecules, including YAP, but whether and how FGFR1 regulates tumor immune evasion remain largely unclear.

METHODS

LSQCC cells were modified to increase or decrease the expression of FGFR1, YAP and PD-L1, as assessed by molecular assays. After FGFR1 knockdown, cancer cells were assessed after cocultured with Jurkat T cells in vitro, and the tumor microenvironment were analyzed in C57BL/6 mice. The effect of the combination of FGFR1 knockdown and PD-1 blockade was also explored.

RESULTS

In human LSQCC, activation of FGFR1 was positively correlated with transcription of PD-L1. In H520 and HCC95 cells, FGFR1 upregulated PD-L1 expression via YAP, and YAP initiated the transcription of PD-L1 after binding to its promoter region. FGFR1 knockdown decreased tumor growth, reduced immune escape and induced reactivation of CD8+ T cells. The combination of FGFR1 knockdown and PD-1 blockade synergistically exerted antitumor effects.

CONCLUSIONS

The FGFR1/YAP/PD-L1 regulatory axis mediates tumor-associated immune suppression in lung squamous cell carcinoma, and FGFR1 knockdown reactivates T cells in the tumor microenvironment. Synergistic inhibition of both FGFR1 and PD-1/PD-L1 pathways may be a possible treatment for lung cancer patients.