FERMT1 promotes cell migration and invasion in non-small cell lung cancer via regulating PKP3-mediated activation of p38 MAPK signaling.

BACKGROUND: Fermitin family member 1 (FERMT1) is highly expressed in many tumors and acts as an oncogene. Nonetheless, the precise function of FERMT1 in non-small cell lung cancer (NSCLC) has not been clearly elucidated. METHODS: Bioinformatics software predicted the FERMT1 expression in NSCLC. Transwell assays facilitated the detection of NSCLC cell migration and invasion. Western blotting techniques were employed to detect the protein levels regulated by FERMT1. RESULTS: FERMT1 exhibited high expression levels in NSCLC and was linked to the patients' poor prognosis, as determined by a variety of bioinformatics predictions combined with experimental verification. FERMT1 promoted the migration and invasion of NSCLC and regulated epithelial to mesenchymal transition (EMT) -related markers. Further studies showed that FERMT1 could up-regulate the expression level of plakophilin 3(PKP3). Further research has indicated that FERMT1 can promote cell migration and invasion via up-regulating PKP3 expression. By exploring downstream signaling pathways, we found that FERMT1 has the capability to activate the p38 mitogen-activated protein kinases (p38 MAPK) signaling pathway, and knocking down PKP3 can counteract the activation induced by FERMT1 overexpression. CONCLUSIONS: FERMT1 was highly expressed in NSCLC and can activate the p38 MAPK signaling pathway through up-regulation of PKP3, thus promoting the invasion and migration of NSCLC.

FERMT1 contributes to the migration and invasion of nasopharyngeal carcinoma through epithelial-mesenchymal transition and cell cycle arrest.

BACKGROUND: Fermitin family member 1 (FERMT1) is significantly overexpressed in human cancers and associated with poor prognosis, but its contributions to tumorigenesis and nasopharyngeal carcinoma (NPC) progression remain unclear. METHODS: The public GEO database was examined to investigate the role of FERMT1. Immunohistochemistry (IHC) staining of FERMT1 was performed in NPC tissues to corroborate the results. Western blotting and qRT-PCR were performed to test the expression of related proteins and mRNAs. Cell counting kit-8 assay (CCK8 assay) and colony formation assays were carried out to investigate the association of FERMT1 expression with NPC cell proliferation. The wound healing assay and Transwell assay were used to detect the migration and invasion of NPC cells. Flow cytometric analysis was conducted to detect the cell cycle transition of NPC cells. Co-immunoprecipitation (Co-IP) was employed to identify the correlation of FEMRT1 and Nod-like receptor family protein 3 (NLRP3). Xenograft tumors were generated to investigate the effect of FERMT1 on the growth of NPC cells in vivo. RESULTS: Here, we found that FERMT1 was upregulated in NPC tissues and correlated with the clinicopathological characteristics of NPC patients. Moreover, knockdown of FERMT1 significantly decreased cell proliferation, migration and invasion by mediating epithelial-mesenchymal transition (EMT) and cell cycle arrest of NPC cells both in vitro and in vivo. Knockdown FERMT1 inhibited EMT through directly binding to the NLRP3 and inhibited NF-kB signaling pathway. CONCLUSION: These data indicated that FERMT1 could be a good potential therapeutic target for NPC treatment.

Examination of FERMT1 expression in placental chorionic villi and its role in HTR8-SVneo cell invasion.

Transmembrane integrin receptors mediate cell-extracellular matrix as well as cell-cell adhesion. As placental trophoblast cells undergo differentiation they display changes in integrin expression or switching, but the mechanism(s) of integrin activation that supports this differentiation is still unknown. The Fermitin family of adapter proteins (FERMT 1-3) are integrin activators that mediate integrin-mediated signaling. In this study, we examined the spatiotemporal pattern of expression of FERMT1 in human chorionic villi throughout gestation and its role in HTR8-SVneo substrate adhesion and invasion. Placental villous tissue was obtained from patients undergoing elective terminations at weeks 8-14, as well as from term deliveries at weeks 37-40 and analyzed by immunofluorescence. Additionally, HTR8-SVneo trophoblast cells were transfected with FERMT1-specific siRNA or non-targeting siRNA (control) and used in cell-substrate adhesion as well as invasion assays. FERMT1 was primarily localized to membrane-associated regions at the base or around the periphery of the villous cytotrophoblast and proximal as well as distal cell column trophoblast. FERMT1 was also localized to endothelial cells of blood vessels in chorionic villi. siRNA-mediated depletion of FERMT1 in HTR8-SVneo cells did not markedly alter HTR8-SVneo cell-substrate adhesion but did significantly decrease invasion (P < 0.05) compared to control cells. These novel findings identify the presence of the integrin activator FERMT1 in trophoblast cells and that FERMT1 can regulate HTR8-SVneo cell invasion. FERMT1 may directly influence integrin activation and the subsequent integrin-mediated signaling and differentiation that underlies the acquisition of the invasive trophoblast phenotype in vivo.

FERMT1 knockdown inhibits oral squamous cell carcinoma cell epithelial-mesenchymal transition by inactivating the PI3K/AKT signaling pathway.

BACKGROUND: The metastasis of oral cancer is one of the main causes of death. However, the mechanisms underlying oral cancer metastasis have not been completely elucidated. Fermitin family member 1 (FERMT1) plays an -oncogene role in many cancers; however, the role of FERMT1 in oral squamous cell cancer (OSCC) remains unclear. METHODS: In this study, OSCC cells were treated with 5 ng/ml recombinant human Transforming growth factor-ß1 (TGF-ß1) protein. FERMT1 expression was measured in OSCC cell lines by RT-qPCR and western blotting. The effect of FERMT1 knockdown on the migration and invasion of OSCC cells was evaluated by Transwell assay. The epithelial-mesenchymal transition (EMT) and PI3K/AKT signaling pathway-related mRNA expression and protein levels were assessed by RT-qPCR and western blotting. RESULTS: We found that FERMT1 expression was elevated in TGF-ß1-induced OSCC cell lines, and knockdown of FERMT1 inhibited the migration and invasion in TGF-ß1-induced OSCC cells. FERMT1 silencing inhibited vimentin, N-cadherin, matrix metalloproteinase 9 (MMP-9) expression and promoted E-cadherin expression, suggesting that FERMT1 silencing inhibited EMT in TGF-ß1-induced OSCC cells. Furthermore, FERMT1 silencing inactivated the PI3K/AKT signaling pathway in TGF-ß1-induced OSCC cells. Activation of the PI3K/AKT signaling pathway reversed the effect of FERMT1 silencing on OSCC cell migration, invasion, and EMT. CONCLUSIONS: FERMT1 silencing inhibits the migration, invasion, and EMT of OSCC cells via inactivation of the PI3K/AKT signaling pathway, suggesting that FERMT1 is a novel and potential therapeutic target for anti-metastatic strategies for OSCC.

A novel pathogenic FERMT1 variant in four families with Kindler syndrome in Argentina.

BACKGROUND: Kindler syndrome is a rare genodermatosis. Major clinical criteria include acral blistering in infancy and childhood, progressive poikiloderma, skin atrophy, abnormal photosensitivity, and gingival fragility. METHODS: FERMT1 gene was sequenced in 5 patients with a clinical diagnosis of Kindler syndrome. RESULTS: We report a novel pathogenic variant detected in four unrelated families of Paraguayan origin, where one nucleotide deletion in FERMT1 gene (c.450delG) is predicted to cause a frameshift mutation leading to loss of function. Haplotype analysis revealed the propagation of an ancestral allele through this population. CONCLUSIONS: The identification of this recurrent pathogenic variant enables optimization of molecular detection strategies in our patients, reducing the cost of diagnosis.

FERMT1 promoter mutations in patients with Kindler syndrome.

Mutations in the FERMT1 gene, encoding the focal adhesion protein kindlin-1 underlie the Kindler syndrome (KS), an autosomal recessive skin disorder with a phenotype comprising skin blistering, photosensitivity, progressive poikiloderma with extensive skin atrophy, and propensity to skin cancer. The FERMT1 mutational spectrum comprises gross genomic deletions, splice site, nonsense, and frameshift mutations, which are scattered over the coding region spanning exon 2-15. We now report three KS families with mutations affecting the promoter region of FERMT1. Two of these mutations are large deletions (∼38.0 and 1.9 kb in size) and one is a single nucleotide variant (c.-20A>G) within the 5' untranslated region (UTR). Each mutation resulted in loss of gene expression in patient skin or cultured keratinocytes. Reporter assays showed the functional relevance of the genomic regions deleted in our patients for FERMT1 gene transcription and proved the causal role of the c.-20A>G variant in reducing transcriptional activity.

FERMT1 suppression induces anti-tumor effects and reduces stemness in glioma cancer cells.

OBJECTIVE: Glioma is a leading cause of mortality worldwide, its recurrence poses a major challenge in achieving effective treatment outcomes. Cancer stem cells (CSCs) have emerged as key contributors to tumor relapse and chemotherapy resistance, making them attractive targets for glioma cancer therapy. This study investigated the potential of FERMT1 as a prognostic biomarker and its role in regulating stemness through cell cycle in glioma. METHODS: Using data from TCGA-GBM, GSE4290, GSE50161 and GSE147352 for analysis of FERMT1 expression in glioma tissues. Then, the effects of FERMT1 knockdown on cell cycle, proliferation, sphere formation ability, invasion and migration were investigated. The influences of FERMT1 on expression of glycolysis-related proteins and levels of ATP, glucose, lactate and G6PDH were also explored. Furthermore, the effects of FERMT1 knockdown on cellular metabolism were evidenced. RESULTS: Significant upregulation of FERMT1 in glioma tissues was observed. Silencing FERMT1 not only affected the cell cycle but also led to a notable reduction in proliferation, invasion and migration. The expression of glycolysis-associated proteins including GLUT1, GLUT3, GLUT4, and SCO2 were reduced by FERMT1 knockdown, resulted in increased ATP and glucose as well as decreased lactic acid and G6PDH levels. FERMT1 knockdown also inhibited cellular metabolism. Moreover, FERMT1 knockdown significantly reduced sphere diameter, along with inhibiting the expression of transcription factors associated with stemness in glioma cells. CONCLUSION: These findings demonstrated that FERMT1 could be an ideal target for the advancement of innovative strategies against glioma treatment via modulating cellular process involved in stemness regulation and metabolism.

Kindler Syndrome Presenting as Colitis in an Infant.

Kindler syndrome (KS) is an autosomal recessive genodermatosis characterized by skin atrophy, blistering, photosensitivity, and mucosal inflammation. We present a unique case of KS with early and severe neonatal onset in a two-month-old female who presented with severe failure to thrive (FTT) and chronic diarrhea since birth. The infant also had multiple fluid-filled cysts on her foot since birth, which resolved and reappeared at different sites. Anemia, hyponatremia, and coloboma of the right iris were also observed. Whole exome sequencing revealed a homozygous mutation in the FERMT1 gene, confirming the diagnosis of KS. Our case demonstrates a distinct clinical phenotype involving severe colitis and FTT in addition to the typical skin manifestations of KS. This atypical presentation highlights the need for further investigations to gain insights into the impact of the kindlin-1 defect on organs beyond the skin and to explore potential therapeutic approaches for managing severe colitis in affected patients.

FERMT1 Is a Prognostic Marker Involved in Immune Infiltration of Pancreatic Adenocarcinoma Correlating with m6A Modification and Necroptosis.

As an important member of the kindlin family, fermitin family member 1 (FERMT1) can interact with integrin and its aberrant expression involves multiple tumors. However, there are few systematic studies on FERMT1 in pancreatic carcinoma (PAAD). We used several public databases to analyze the expression level and clinicopathological characteristics of FERMT1 in PAAD. Meanwhile, the correlation between FERMT1 expression and diagnostic and prognostic value, methylation, potential biological function, immune infiltration, and sensitivity to chemotherapy drugs in PAAD patients were investigated. FERMT1 was significantly up-regulated in PAAD and correlated with T stage, and histologic grade. High FERMT1 expression was closely connected with poor prognosis and can be used to diagnose PAAD. Moreover, the methylation of six CpG sites of FERMT1 was linked to prognosis, and FERMT1 expression was significantly related to N6-methyladenosine (m6A) modification. Functional enrichment analysis revealed that FERMT1 co-expression genes participated in diverse biological functions including necroptosis. In addition, the expression of FERMT1 was associated with immune cell infiltration and the expression of immune checkpoint molecules. Finally, FERMT1 overexpression may be sensitive to chemotherapy drugs such as Palbociclib, AM-5992 and TAE-226. FERMT1 can serve as a diagnostic and prognostic marker of PAAD, which is connected with immune cell infiltration and the modulation of m6A and necroptosis.

FERM domain containing kindlin 1 knockdown attenuates inflammation induced by intracerebral hemorrhage in rats via NLR family pyrin domain containing 3/nuclear factor kappa B pathway.

Intracerebral hemorrhage (ICH) is an incurable neurological disease. Microglia activation and its related inflammation contribute to ICH-associated brain damage. FERM domain containing kindlin 1 (FERMT1) is an integrin-binding protein that participates in microglia-associated inflammation, but its role in ICH is unclear. An ICH model was constructed by injecting 50 µl of autologous blood into the bregma of rats. FERMT1 siRNA was injected into the right ventricle of the rat for knockdown of FERMT1. A significant striatal hematoma was observed in ICH rats. FERMT1 knockdown reduced the water content of brain tissue, alleviated brain hematoma and improved behavioral function in ICH rats. FERMT1 knockdown reduced microglia activity, inhibited NLR family pyrin domain containing 3 (NLRP3) inflammasome activity and decreased the expression of inflammatory factors including IL-1ß and IL-18 in the peri-hematoma tissues. BV2 microglial cells were transfected with FERMT1 siRNA and incubated with 60 µM Hemin for 24 h. Activation of NLRP3 inflammasome induced by hemin were reduced in microglia when FERMT1 was knocked down, leading to decreased production of inflammatory factors IL-1ß and IL-18. In addition, knockdown of FERMT1 prevented the activation of nuclear factor kappa B (NF-κB) signaling pathway in vivo and in vitro. Our findings suggested that down-regulation of FERMT1 attenuated microglial inflammation and brain damage induced by ICH via NLRP3/NF-κB pathway. FERMT1 is a key regulator of inflammatory damage in rats after ICH.

Novel biomarkers identified in triple-negative breast cancer through RNA-sequencing.

BACKGROUND AND AIMS: Triple-negative breast cancer (TNBC) is a subtype of breast cancer with a poor prognosis due to its aggressive biological behavior and lack of therapeutic targets. Here, we aimed to identify specific biomarkers for TNBC by using RNA-sequencing and bioinformatics analysis. MATERIALS AND METHODS: Fresh breast tumor tissues were obtained from 34 patients who were admitted to the Breast Center, Peking University People's Hospital, from June 2020 to December 2020; the patients were pathologically diagnosed with primary breast cancer and underwent surgery for the resection of tumor tissues. Tumor-tissue RNA was extracted and the generated cDNA libraries were sequenced using the NextSeq platform, after which the differentially expressed genes (DEGs) between TNBC and other subtypes of breast cancer were identified and DEG functional-enrichment analysis was performed. Next, weighted gene co-expression network analysis (WGCNA) was used to identify the most significant module and hub genes in TNBC, and then the correlations between the hub genes and the prognosis of TNBC patients were analyzed through survival analysis. Lastly, qRT-PCR analysis was used to validate the expression levels of hub genes in tumor tissues from TNBC and other subtypes of breast cancer. RESULTS: Comparison of TNBC tissues and tissues from other subtypes of breast cancer led to the identification of 273 DEGs in TNBC: 172 upregulated and 101 downregulated genes. In Gene Ontology analysis of the DEGs, five terms were significantly enriched, "developmental process," "anatomical structure development," "tissue development," "cell cycle," and "epithelium development," and in Kyoto Encyclopedia of Genes and Genomes pathway analysis, the most significantly enriched pathways for all DEGs were "cell cycle," "mitophagy-animal," and "autophagy-animal." Furthermore, we identified the core module related to TNBC and screened for hub genes by using WGCNA, and after verifying the top 100 genes based on survival analysis, we selected four genes as the hub genes: SERPINB4, SMR3A, FERMT1, and STARD4; elevated expression of these genes was associated with poor overall survival (OS) of TNBC patients. Notably, qRT-PCR results indicated that FERMT1 mRNA expression was significantly upregulated in TNBC samples. CONCLUSION: The DEG profiles between tissues from TNBC and other subtypes of breast cancer were identified using RNA-sequencing and bioinformatics analysis. FERMT1 was significantly upregulated in TNBC tumor tissues, and increased expression of FERMT1 was associated with poor OS of TNBC patients. FERMT1 could serve as a specific biomarker of and therapeutic target in TNBC.

Urological Manifestations of Kindler Syndrome: A Case Report.

Kindler syndrome is a rare autosomal recessive skin disorder. It results from mutation of the FERM domain containing kindlin-1 (FERMT1) that leads to loss of function of kindlin-1, which plays a role in keratinocyte adhesion, polarization, proliferation, and migration. It is characterized by skin blistering, photosensitivity, progressive poikiloderma, and skin atrophy. The mucosae genitourinary system is commonly affected. The urological manifestations include meatal stenosis, urethral stricture, phimosis, and scarring of the glans penis. Skin biopsy with genetic analysis is the gold standard for diagnosis. Genetic counseling and a multidisciplinary approach are the mainstays of treatment.

FERMT1 promotes gastric cancer progression by activating the NF-κB pathway and predicts poor prognosis.

Recent studies have reported that FERMT1, a newly discovered adhesion protein, contributes to an aggressive phenotype in several solid malignancies. However, the function and regulatory mechanism of FERMT1 in gastric cancer remain unknown. We found that FERMT1 was overexpressed in gastric cancer tissues compared with normal tissues. Clinical data analysis indicated that the expression of FERMT1 correlated with the overall survival of gastric cancer patients. Patients with higher FERMT1 expression had lower survival rates than patients with lower FERMT1 expression. We established stable cell lines with FERMT1 knockdown and overexpression. In vitro and in vivo experiments indicated that knockdown of FERMT1 inhibited the proliferation, invasion, metastasis, and epithelial-mesenchymal transition of gastric cancer cells. Mechanistically, FERMT1 was found to activate NF-κB signaling by promoting the degradation of IκBα, thereby promoting gastric cancer. These results provide new evidence of the oncogenic effects of FERMT1 in gastric cancer and suggest that FERMT1 might be a promising target for gastric cancer treatment.

Aggressive periodontitis associated with Kindler syndrome in a large Kindler syndrome pedigree.

Talo-Yildirim T, Acun-Kaya F, Taskesen M, Dündar S, Bozoglan A, Tekin GG, Akdeniz S. Aggressive periodontitis associated with Kindler syndrome in a large Kindler syndrome pedigree. Turk J Pediatr 2017; 59: 56-61. Kindler syndrome (KS) is a rare genetic disorder. The clinical features include aggressive periodontal disease and severe desquamative gingivitis. Five individuals with KS were assessed by oral examination, radiographic analysis and periodontal measurements. All the patients' indexes were recorded prior to periodontal treatment and at the end of the 1th, 3th , 6th, 9th and 12th month respectively. All the patients had improvement of periodontal status and enhancement in index scores. The affected individuals were previously screened for FERMT1 mutations. KS patients' periodontal disease activity could be taken under control with regular follow-up.

A novel large deletion mutation of FERMT1 gene in a Chinese patient with Kindler syndrome.

Kindler syndrome (KS; OMIM 173650) is a rare autosomal recessive skin disorder, which results in symptoms including blistering, epidermal atrophy, increased risk of cancer, and poor wound healing. The majority of mutations of the disease-determining gene (FERMT1 gene) are single nucleotide substitutions, including missense mutations, nonsense mutations, etc. Large deletion mutations are seldom reported. To determine the mutation in the FERMT1 gene associated with a 7-year-old Chinese patient who presented clinical manifestation of KS, we performed direct sequencing of all the exons of FERMT1 gene. For the exons 2-6 without amplicons, we analyzed the copy numbers using quantitative real-time polymerase chain reaction (qRT-PCR) with specific primers. The deletion breakpoints were sublocalized and the range of deletion was confirmed by PCR and direct sequencing. In this study, we identified a new 17-kb deletion mutation spanning the introns 1-6 of FERMT1 gene in a Chinese patient with severe KS phenotypes. Her parents were carriers of the same mutation. Our study reported a newly identified large deletion mutation of FERMT1 gene involved in KS, which further enriched the mutation spectrum of the FERMT1 gene.