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Background: The active metabolite of vitamin A (retinol) is retinoic acid (RA). RA is essential for developing several organs as a signaling molecule that is tightly regulated during embryogenesis. We explored the teratogenic effects of RA on forebrain and spinal cord development modified by cyclin-dependent kinase inhibitor 1B (CDKN1B), as the mechanism underlying RA's teratogenic impacts requires further investigation. The study involved four groups of pregnant mice: the negative control group, the positive control group treated with dimethyl sulfoxide (DMSO) diluted in sunflower oil, the RA-treated group receiving a low dosage (5 mg/kg), and the RA-treated group receiving a high dosage (10 mg/kg). The treatment groups received daily intraperitoneal RA dissolved in DMSO and diluted with sunflower oil on gestational days 10.5, 11.5, and 12.5. On day 13.5 of pregnancy, the pregnant mice were euthanized by cervical dislocation, and immunohistochemical analyses of brain and spinal cord tissues were performed. Results: Morphologically, we observed a decrease in the number of implantation sites and the presence of hematomas in several uterus areas in the high-dose RA (10 mg/kg) group. Additionally, RA was shown to cause adverse changes in uterine weight and length. RA treatment indicated elevated levels of CDKN1B expression in spinal cord development, the diencephalon, and the telencephalon. Conclusion: Our findings demonstrated that by activating CDKN1B as an RA target gene for cell cycle arrest, an excess of RA during brain development in mouse embryos can induce cell undifferentiation during development. [ABSTRACT FROM AUTHOR]

Abstract Background The active metabolite of vitamin A (retinol) is retinoic acid (RA). RA is essential for developing several organs as a signaling molecule that is tightly regulated during embryogenesis. We explored the teratogenic effects of RA on forebrain and spinal cord development modified by cyclin-dependent kinase inhibitor 1B (CDKN1B), as the mechanism underlying RA's teratogenic impacts requires further investigation. The study involved four groups of pregnant mice: the negative control group, the positive control group treated with dimethyl sulfoxide (DMSO) diluted in sunflower oil, the RA-treated group receiving a low dosage (5 mg/kg), and the RA-treated group receiving a high dosage (10 mg/kg). The treatment groups received daily intraperitoneal RA dissolved in DMSO and diluted with sunflower oil on gestational days 10.5, 11.5, and 12.5. On day 13.5 of pregnancy, the pregnant mice were euthanized by cervical dislocation, and immunohistochemical analyses of brain and spinal cord tissues were performed. Results Morphologically, we observed a decrease in the number of implantation sites and the presence of hematomas in several uterus areas in the high-dose RA (10 mg/kg) group. Additionally, RA was shown to cause adverse changes in uterine weight and length. RA treatment indicated elevated levels of CDKN1B expression in spinal cord development, the diencephalon, and the telencephalon. Conclusion Our findings demonstrated that by activating CDKN1B as an RA target gene for cell cycle arrest, an excess of RA during brain development in mouse embryos can induce cell undifferentiation during development.

Abstract Background Extrachromosomal circular DNA (eccDNA), a kind of circular DNA that originates from chromosomes, carries complete gene information, particularly the oncogenic genes. This study aimed to examine the contributions of FAM84B induced by eccDNA to prostate cancer (PCa) development and the biomolecules involved. Methods The presence of eccDNA in PCa cells and the FAM84B transcripts that eccDNA carries were verified by outward and inward PCR. The effect of inhibition of eccDNA synthesis on FAM84B expression in PCa cells was analyzed by knocking down Lig3. The impact of FAM84B on the growth and metastases of PCa cells was verified by Cell Counting Kit-8 (CCK8), EdU, transwell assays, and a xenograft mouse model. Chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) and dual-luciferase reporter assays were carried out to examine the effect of FAM84B/MYC on WWP1 transcription, and a co-immunoprecipitation (Co-IP) assay was conducted to verify the modification of CDKN1B by WWP1. The function of this molecular axis in PCa was explored by rescue assays. Results The inhibited eccDNA synthesis significantly downregulated FAM84B in PCa cells, thereby attenuating the growth and metastasis of PCa. FAM84B promoted the transcription of WWP1 by MYC by activating the expression of MYC coterminous with the 8q24.21 gene desert in a beta catenin-dependent approach. WWP1 transcription promoted by MYC facilitated the ubiquitination and degradation of CDKN1B protein and inversely attenuated the repressive effect of CDKN1B on MYC expression. Exogenous overexpression of CDKN1B blocked FAM84B-activated MYC/WWP1 expression, thereby inhibiting PCa progression. Conclusions FAM84B promoted by eccDNA mediates degradation of CDKN1B via MYC/WWP1, thereby accelerating PCa progression.

Background: Extrachromosomal circular DNA (eccDNA), a kind of circular DNA that originates from chromosomes, carries complete gene information, particularly the oncogenic genes. This study aimed to examine the contributions of FAM84B induced by eccDNA to prostate cancer (PCa) development and the biomolecules involved. Methods: The presence of eccDNA in PCa cells and the FAM84B transcripts that eccDNA carries were verified by outward and inward PCR. The effect of inhibition of eccDNA synthesis on FAM84B expression in PCa cells was analyzed by knocking down Lig3. The impact of FAM84B on the growth and metastases of PCa cells was verified by Cell Counting Kit-8 (CCK8), EdU, transwell assays, and a xenograft mouse model. Chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) and dual-luciferase reporter assays were carried out to examine the effect of FAM84B/MYC on WWP1 transcription, and a co-immunoprecipitation (Co-IP) assay was conducted to verify the modification of CDKN1B by WWP1. The function of this molecular axis in PCa was explored by rescue assays. Results: The inhibited eccDNA synthesis significantly downregulated FAM84B in PCa cells, thereby attenuating the growth and metastasis of PCa. FAM84B promoted the transcription of WWP1 by MYC by activating the expression of MYC coterminous with the 8q24.21 gene desert in a beta catenin-dependent approach. WWP1 transcription promoted by MYC facilitated the ubiquitination and degradation of CDKN1B protein and inversely attenuated the repressive effect of CDKN1B on MYC expression. Exogenous overexpression of CDKN1B blocked FAM84B-activated MYC/WWP1 expression, thereby inhibiting PCa progression. Conclusions: FAM84B promoted by eccDNA mediates degradation of CDKN1B via MYC/WWP1, thereby accelerating PCa progression. [ABSTRACT FROM AUTHOR]

Context Germline CDKN1B variants predispose patients to multiple endocrine neoplasia type 4 (MEN4), a rare MEN1-like syndrome, with <100 reported cases since its discovery in 2006. Although CDKN1B mutations are frequently suggested to explain cases of genetically negative MEN1, the prevalence and phenotype of MEN4 patients is poorly known, and genetic counseling is unclear. Objective To evaluate the prevalence of MEN4 in MEN1-suspected patients and characterize the phenotype of MEN4 patients. Design Retrospective observational nationwide study. Narrative review of literature and variant class reassessment. Patients We included all adult patients with class 3/4/5 CDKN1B variants identified by the laboratories from the French Oncogenetic Network on Neuroendocrine Tumors network between 2015 and 2022 through germline genetic testing for MEN1 suspicion. After class reassessment, we compared the phenotype of symptomatic patients with class 4/5 CDKN1B variants (ie, with genetically confirmed MEN4 diagnosis) in our series and in literature with 66 matched MEN1 patients from the UMD-MEN1 database. Results From 5600 MEN1-suspected patients analyzed, 4 with class 4/5 CDKN1B variant were found (0.07%). They presented with multiple duodenal NET, primary hyperparathyroidism (PHPT) and adrenal nodule, isolated PHPT, PHPT, and pancreatic neuroendocrine tumor. We listed 29 patients with CDKN1B class 4/5 variants from the literature. Compared with matched MEN1 patients, MEN4 patients presented lower NET incidence and older age at PHPT diagnosis. Conclusion The prevalence of MEN4 is low. PHPT and pituitary adenoma represent the main associated lesions, NETs are rare. Our results suggest a milder and later phenotype than in MEN1. Our observations will help to improve genetic counseling and management of MEN4 families. [ABSTRACT FROM AUTHOR]

Background: A recent high-throughput sequencing study revealed an anomalous underexpression of circular RNA UBAP2 (circUBAP2) in acute myocardial infarction (AMI), yet its biological function within this context remains elusive. This study aims to unravel whether circUBAP2 is instrumental in modulating the pathogenesis of AMI and to illuminate the underlying molecular mechanisms at play. Results: circUBAP2 was abnormally low expressed in AMI. Inducing circUBAP2 ameliorated hypoxia-induced myocardial cell injury by enhancing cellular viability, and decreasing lactate dehydrogenase release, apoptosis, inflammation, and oxidative damage. circUBAP2 targeted miR-148b-3p, miR-148b-3p overexpression offset circUBAP2-induced cardioprotection. Cyclin-dependent kinase inhibitor 1B (CDKN1B) was mediated by miR-148b-3p, and CDKN1B upregulation suppressed the deleterious effect of circUBAP2 silencing on hypoxic AC16 cells. In addition, overexpression of circUBAP2 improved myocardial injury, decreased myocardial cell apoptosis, and alleviated inflammation and oxidative stress in AMI mice. Conclusions: circUBAP2 ameliorates AMI by competitively binding to miR-148b-3p and mediating CDKN1B expression.How to cite: Li F, Xu L, Ou J, et al. circUBAP2 ameliorates hypoxia-induced acute myocardial injury by competing with miR-148b-3p and mediating CDKN1B expression. Electron J Biotechnol 2024;68. https://doi.org/10.1016/j.ejbt.2023.11.003.

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally, with the potential to progress to non-alcoholic steatohepatitis (NASH), cirrhosis, and even hepatocellular carcinoma. Given the absence of effective treatments to halt its progression, novel molecular approaches to the NAFLD diagnosis and treatment are of paramount importance. Methods: Firstly, we downloaded oxidative stress-related genes from the GeneCards database and retrieved NAFLD-related datasets from the GEO database. Using the Limma R package and WGCNA, we identified differentially expressed genes closely associated with NAFLD. In our study, we identified 31 intersection genes by analyzing the intersection among oxidative stress-related genes, NAFLD-related genes, and genes closely associated with NAFLD as identified through Weighted Gene Co-expression Network Analysis (WGCNA). In a study of 31 intersection genes between NAFLD and Oxidative Stress (OS), we identified three hub genes using three machine learning algorithms: Least Absolute Shrinkage and Selection Operator (LASSO) regression, Support Vector Machine - Recursive Feature Elimination (SVM-RFE), and RandomForest. Subsequently, a nomogram was utilized to predict the incidence of NAFLD. The CIBERSORT algorithm was employed for immune infiltration analysis, single sample Gene Set Enrichment Analysis (ssGSEA) for functional enrichment analysis, and Protein-Protein Interaction (PPI) networks to explore the relationships between the three hub genes and other intersecting genes of NAFLD and OS. The distribution of these three hub genes across six cell clusters was determined using single-cell RNA sequencing. Finally, utilizing relevant data from the Attie Lab Diabetes Database, and liver tissues from NASH mouse model, Western Blot (WB) and Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) assays were conducted, this further validated the significant roles of CDKN1B and TFAM in NAFLD. Results: In the course of this research, we identified 31 genes with a strong association with oxidative stress in NAFLD. Subsequent machine learning analysis and external validation pinpointed two genes: CDKN1B and TFAM, as demonstrating the closest correlation to oxidative stress in NAFLD. Conclusion: This investigation found two hub genes that hold potential as novel targets for the diagnosis and treatment of NAFLD, thereby offering innovative perspectives for its clinical management. [ABSTRACT FROM AUTHOR]

The cyclin-dependent kinase inhibitor 1B (CDKN1B) gene, which encodes the p27Kip1 protein, is important in regulating the cell cycle process and cell proliferation. Its role in breast cancer prognosis is controversial. We evaluated the significance and predictive role of CDKN1B expression in breast cancer prognosis. We investigated the clinicopathologic factors, survival rates, immune cells, gene sets, and prognostic models according to CDKN1B expression in 3794 breast cancer patients. We performed gene set enrichment analysis (GSEA), in silico cytometry, pathway network analyses, gradient boosting machine (GBM) learning, and in vitro drug screening. High CDKN1B expression levels in breast cancer correlated with high lymphocyte infiltration signature scores and increased CD8+ T cells, both of which were associated with improved prognosis in breast cancer. which were associated with a better prognosis. CDKN1B expression was associated with gene sets for the upregulation of T-cell receptor signaling pathways and downregulation of CD8+ T cells. Pathway network analysis revealed a direct link between CDKN1B and the pathway involved in the positive regulation of the protein catabolic process pathway. In addition, an indirect link was identified between CDKN1B and the T-cell receptor signaling pathway. In in vitro drug screening, BMS-345541 demonstrated efficacy as a therapeutic targeting of CDKN1B, effectively impeding the growth of breast cancer cells characterized by low CDKN1B expression. The inclusion of CDKN1B expression in GBM models increased the accuracy of survival predictions. CDKN1B expression plays a significant role in breast cancer progression, implying that targeting CDKN1B might be a promising strategy for treating breast cancer. [ABSTRACT FROM AUTHOR]

Abstract Background Human health and life are threatened by cancer with high morbidity and mortality worldwide. In many experiments, CDKN1B level is associated with cancer risk, Nevertheless, no pan-cancer analysis has been conducted on CDKN1B in human cancers. Methods With the help of bioinformatics, a pan-cancer analysis was conducted on the expression levels of CDKN1B in cancer tissues and adjacent tissues from the TCGA, CPTAC and GEO databases. The CDKN1B expression levels in tumor patients was further validated using immunohistochemistry (IHC) and quantitative real-time PCR. Results In the study, we first investigated the cancer-related roles of CDKN1B’s in 40 tumors with malignancy. The CDKN1B gene encodes the p27Kip1 protein, which can block the production cyclin-dependent kinase (CDK), which is obviously related to the function and survival of cancer cells and alters the prognosis of cancer patients. Furthermore, CDKN1B function requires both protein processing and RNA metabolism. Additionally, the elevated expression of the CDKN1B gene and protein was validated in several cancer tissues from the patients. Conclusions These results showed that the levels of CDKN1B were considerably different in a number of cancer tissues, offering a potential future target for cancer therapy.

Purpose: Multiple endocrine neoplasia type 4 (MEN4) is a rare multiglandular endocrine neoplasia syndrome, associated with a wide tumor spectrum but hallmarked by primary hyperparathyroidism, which represents the most common clinical feature, followed by pituitary (functional and non-functional) adenomas, and neuroendocrine tumors. MEN4 clinically overlaps MEN type 1 (MEN1) but differs from it for milder clinical features and an older patient's age at onset. The underlying mutated gene, CDKN1B, encodes the cell cycle regulator p27, implicated in cellular proliferation, motility and apoptosis. Given the paucity of MEN4 cases described in the literature, possible genotype–phenotype correlations have not been thoroughly assessed, and specific clinical recommendations are lacking. The present review provides an extensive overview of molecular genetics and clinical features of MEN4, with the aim of contributing to delineate peculiar strategies for clinical management, screening and follow-up of the last and least known MEN syndrome. Methods: A literature search was performed through online databases like MEDLINE and Scopus. Conclusions: MEN4 is much less common that MEN1, tend to present later in life with a more indolent course, although involving the same primary organs as MEN1. As a consequence, MEN4 patients might need specific diagnostic and therapeutic approaches and a different strategy for screening and follow-up. Further studies are needed to assess the real oncological risk of MEN4 carriers, and to establish a standardized screening protocol. Furthermore, a deeper understanding of molecular genetics of MEN4 is needed in order to explore p27 as a novel therapeutic target. [ABSTRACT FROM AUTHOR]

Background: Human gliomas are aggressive brain tumors characterized by uncontrolled cell proliferation. Differential expression of Polycomb repressive complex 2 (PRC2) has been reported in various subtypes of glioma. However, the role of PRC2 in uncontrolled growth in glioma and its underlying molecular mechanisms remain to be elucidated. Objective: We aimed to investigate the functional role of PRC2 in human glioblastoma cell growth by silencing SUZ12, the non-catalytic core component of PRC2. Methods: Knockdown of SUZ12 was achieved by infecting T98G cells with lentivirus carrying sequences specifically targeting SUZ12 (shSUZ12). Gene expression was examined by quantitative PCR and western analysis. The impact of shSUZ12 on cell growth was assessed using a cell proliferation assay. Cell cycle distribution was analyzed by flow cytometry, and protein stability was evaluated in cycloheximide-treated cells. Subcellular localization was examined through immunofluorescence staining and biochemical cytoplasmic-nuclear fractionation. Gene expression analysis was also performed on human specimens from normal brain and glioblastoma patients. Results: SUZ12 knockdown (SUZ12 KD) led to widespread decrease in the PRC2-specific histone mark, accompanied by a slowdown of cell proliferation through G1 arrest. In SUZ12 KD cells, the degradation of CDKN1B protein was reduced, resulting from alterations in the MYC-SKP2-CDKN1B axis. Furthermore, nuclear localization of CDKN1B was enhanced in SUZ12 KD cells. Analysis of human glioblastoma samples yielded increased expression of EZH2 and MYC along with reduced CDKN1B compared to normal human brain tissue. Conclusion: Our findings suggest a novel role for SUZ12 in cell proliferation through post-translational regulation of CDKN1B in glioblastoma. [ABSTRACT FROM AUTHOR]

Gastrointestinal epithelial cells respond to milk‐born molecules throughout breastfeeding, influencing growth, and development. The rapid renewal of the small intestine depends on the proliferation in the crypt that drives cell fates. We used early weaning model to investigate immediate and late effects of breastfeeding on proliferation, differentiation of jejunal epithelial cells. Wistar rats were either allowed to suckle (S) until 21 postnatal days or submitted to early weaning (EW) at 15 days. By comparing ages (18, 60, and 120 days), we found that EW decreased Ki67 indices and villi height at 18 and 60 days (p < 0.05), and at 120 days they were similar between diets. Proliferative reduction and augmented expression of Cdkn1b (p27 gene) were parallel. In the stem cell niche, EW increased the number and activity (Defa24) of Paneth cells at 18 and 60 days (p < 0.05), and Lgr5 and Ascl2 genes showed inverted responses between ages. Among target cells, EW decreased goblet cell number at 18 and 60 days (p < 0.05) and increased it at 120 days (p < 0.05), whereas enteroendocrine marker genes were differentially altered. EW reduced enterocytes density at 18 days (p < 0.05), and at 120 days this population was decreased (vs. 60 days). Among cell fate crypt‐controlling genes, Notch and Atoh1 were the main targets of EW. Metabolically, intraperitoneal glucose tolerance was immediately reduced (18 days), being reverted until 120 days (p < 0.05). Currently, we showed that breastfeeding has a lifespan influence on intestinal mucosa and on its stem cell compartment. We suggest that, although jejunum absorptive function is granted after early weaning, the long lasting changes in gene expression might prime the mucosa with a different sensitivity to gut disorders that still have to be further explored. [ABSTRACT FROM AUTHOR]

Background: Diabetic nephropathy (DN) is a frequent microvascular complication of diabetes. Glomerular mesangial cell (MC) hypertrophy occurs at the initial phase of DN and plays a critical role in the pathogenesis of DN. Given the role of long non coding RNA (lncRNA) in regulating MC hypertrophy and extracellular matrix (ECM) accumulation, our aim was to identify functional lncRNAs during MC hypertrophy. Methods: Here, an lncRNA, C920021L13Rik (L13Rik for short), was identified to be up-regulated in DN progression. The expression of L13Rik in DN patients and diabetic mice was assessed using quantitative real-time PCR (qRT-PCR), and the function of L13Rik in regulating HG-induced MC hypertrophy and ECM accumulation was assessed through flow cytometry and western blotting analysis. Results: The L13Rik levels were significantly increased while the miR-2861 levels were decreased in the peripheral blood of DN patients, the renal tissues of diabetic mice, and HG-treated MCs. Functionally, both L13Rik depletion and miR-2861 overexpression effectively reduced HG-induced cell hypertrophy and ECM accumulation. Mechanistically, L13Rik functioned as a competing endogenous RNA (ceRNA) to sponge miR-2861, resulting in the de-repression of cyclin-dependent kinase inhibitor 1B (CDKN1B), a gene known to regulate cell cycle and MC hypertrophy. Conclusions: Collectively, the current results demonstrate that up-regulated L13Rik is correlated with DN and may be a hopeful therapeutic target for DN. [ABSTRACT FROM AUTHOR]

Abstract Background Osteoarthritis (OA) is the most prevalent age-related disease in the world. Chondrocytes undergo an age-dependent decline in their proliferation and synthetic capacity, which is the main cause of OA development. However, the intrinsic mechanism of chondrocyte senescence is still unclear. This study aimed to investigate the role of a novel long non-coding RNA (lncRNA), AC006064.4–201 in the regulation of chondrocyte senescence and OA progression and to elucidate the underlying molecular mechanisms. Methods The function of AC006064.4–201 in chondrocytes was assessed using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence (IF) and β-galactosidase staining. The interaction between AC006064.4–201 and polypyrimidine tract-binding protein 1 (PTBP1), as well as cyclin-dependent kinase inhibitor 1B (CDKN1B), was evaluated using RPD-MS, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down assays. Mice models were used to investigate the role of AC006064.4–201 in post-traumatic and age-related OA in vivo. Results Our research revealed that AC006064.4–201 was downregulated in senescent and degenerated human cartilage, which could alleviate senescence and regulate metabolism in chondrocytes. Mechanically, AC006064.4–201 directly interacts with PTBP1 and blocks the binding between PTBP1 and CDKN1B mRNA, thereby destabilizing CDKN1B mRNA and decreasing the translation of CDKN1B. The in vivo experiments were consistent with the results of the in vitro experiments. Conclusions The AC006064.4–201/PTBP1/CDKN1B axis plays an important role in OA development and provides new molecular markers for the early diagnosis and treatment of OA in the future. Graphical Abstract Schematic diagram of AC006064.4–201 mechanism. A schematic diagram of the mechanism underlying the effect of AC006064.4–201

Background: Human health and life are threatened by cancer with high morbidity and mortality worldwide. In many experiments, CDKN1B level is associated with cancer risk, Nevertheless, no pan-cancer analysis has been conducted on CDKN1B in human cancers. Methods: With the help of bioinformatics, a pan-cancer analysis was conducted on the expression levels of CDKN1B in cancer tissues and adjacent tissues from the TCGA, CPTAC and GEO databases. The CDKN1B expression levels in tumor patients was further validated using immunohistochemistry (IHC) and quantitative real-time PCR. Results: In the study, we first investigated the cancer-related roles of CDKN1B's in 40 tumors with malignancy. The CDKN1B gene encodes the p27Kip1 protein, which can block the production cyclin-dependent kinase (CDK), which is obviously related to the function and survival of cancer cells and alters the prognosis of cancer patients. Furthermore, CDKN1B function requires both protein processing and RNA metabolism. Additionally, the elevated expression of the CDKN1B gene and protein was validated in several cancer tissues from the patients. Conclusions: These results showed that the levels of CDKN1B were considerably different in a number of cancer tissues, offering a potential future target for cancer therapy. [ABSTRACT FROM AUTHOR]

Abstract Circular RNAs (circRNAs) have been reported to be related to the initiation and progression of chronic obstructive pulmonary disease (COPD) by affecting the function of human bronchial epithelial cells (HBECs). Here, we aimed to investigate the function and mechanism of circ_0006872 in regulating COPD process using cigarette smoke extract (CSE)-induced 16HBEC in vitro. The results showed that circ_0006872 was increased in smokers without or with COPD, especially in smokers with COPD. Also, its expression was dose-dependently up-regulated by CSE exposure in 16HBECs. Functionally, circ_0006872 knockdown dramatically attenuated CSE-evoked proliferation arrest, apoptosis, inflammatory response and oxidative stress in 16HBECs. Mechanistically, circ_0006872/miR-485-3p/cyclin-dependent kinase inhibitor 1B (CDKN1B) formed a competitive endogenous RNA (ceRNA) network. CDKN1B was increased and miR-485-3p was decreased in COPD patients and CSE-induced 16HBECs. MiR-485-3p overexpression or CDKN1B knockdown protected 16HBEC against CSE-induced 16HBEC injury mentioned above. Moreover, rescue experiments showed that circ_0006872 regulated CSE-induced 16HBEC injury via miR-485-3p/CDKN1B axis. Circ_0006872 silencing protected against CSE-induced bronchial epithelial cell injury via miR-485-3p/CDKN1B axis, suggesting the potential application of circ_0006872 in preventing cigarette smoke-induced COPD.

Objective: Multiple endocrine neoplasia type 4 (MEN4) is caused by a CDKN1B germline mutation first described in 2006. Its estimated prevalence is le ss than one per million. The aim of this study was to define the disease characteristics. Methods: A systematic review was performed according to the PRISMA 2020 criteria. A literature search from January 2006 to August 2022 was done using MEDLINE® and Web of ScienceTM. Results: Forty-eight symptomatic patients fulfilled the pre-defined eligi bility criteria. Twenty-eight different CDKN1B variants, mostly missense (21/48, 44%) and frameshift mutations (17/48, 35%), were reported. The majority of patients were women (36/48, 75%). Men became symptomatic at a median age of 32.5 years (ran ge 10–68, mean 33.7 ± 23), whereas the same event was recorded for women at a media n age of 49.5 years (range 5–76, mean 44.8 ± 19.9) (P = 0.25). The most frequently affected endocrine organ was the parathyroid gland (36/48, 75%; uniglandular disease 31/36, 86%), followed by the pituitary gland (21/48, 44%; hormone-secreting 16/21, 76%), the endocrine pancreas (7/48, 15%), and the thyroid gland (4/48, 8%). Tumors of the ad renal glands and thymus were found in three and two patients, respectively. The present ing first endocrine pathology concerned the parathyroid (27/48, 56%) and the pituit ary gland (11/48, 23%). There were one (27/48, 56%), two (13/48, 27%), three (3/48, 6%), or four (5/48, 10%) syn-or metachronously affected endocrine organs in a single patient, respectively. Conclusion: MEN4 is an extremely rare disease, which most frequently affect s women around 50 years of age. Primary hyperparathyroidism as a unigla ndular disease is the leading pathology.

The functional properties of endogenous Schwann cells (SCs) during nerve repair are dynamic. Optimizing the functional properties of SCs at different stages of nerve repair may have therapeutic benefit in improving the repair of damaged nerves. Previous studies showed that miR-221-3p promotes the proliferation and migration of SCs, and miR-338-3p promotes the myelination of SCs. In this study, we established rat models of sciatic nerve injury by bridging the transected sciatic nerve with a silicone tube. We injected a miR-221 lentiviral vector system together with a doxycycline-inducible Tet-On miR-338 lentiviral vector system into the cavity of nerve conduits of nerve stumps to sequentially regulate the biological function of endogenous SCs at different stages of nerve regeneration. We found that the biological function of SCs was sequentially regulated, the diameter and density of myelinated axons were increased, the expression levels of NF200 and myelin basic protein were increased, and the function of injured peripheral nerve was improved using this system. miRNA Target Prediction Database prediction, Nanopore whole transcriptome sequencing, quantitative PCR, and dual luciferase reporter gene assay results predicted and verified Cdkn1b and Nrp1 as target genes of miR-221-3p and miR-338-3p, respectively, and their regulatory effects on SCs were confirmed in vitro. In conclusion, here we established a new method to enhance nerve regeneration through sequential regulation of biological functions of endogenous SCs, which establishes a new concept and model for the treatment of peripheral nerve injury. The findings from this study will provide direct guiding significance for clinical treatment of sciatic nerve injury.

Background & Objective: Breast cancer consists of a heterogeneous group of tumours with different prognosis and is the most common cause of cancer-related mortality among women. In this study, our goal was to evaluate the association of AURKA rs2273535 and CDKN1B rs34330 polymorphisms with risk of female breast cancer in southwest part of Iran. Materials & Methods: This case-control study was done on 50 women with breast cancer and 50 healthy women without any symptoms or family history of breast cancer as the case and control group, respectively. Restriction fragment length polymorphism (RFLP- PCR) technique was designed to determine the AURKA rs2273535 and CDKN1B rs34330 gene polymorphisms. Afterwards, statistical analysis was done by means of SPSS (version 17). Results: In current research, our finding showed that rs2273535 T allele increased the susceptibility of breast cancer (OR:2.58, 95%CI:1.5-31.09, P=0.006). Moreover, T allele in dominant phase could raise the risk of the breast cancer (OR:3.01, 65%CI:1.31-6.92, P=0.009). However, the other polymorphism, CDKN1B rs34330, revealed no associations with increased risk of breast cancer. Conclusion: These findings suggest that AURKA rs2273535 may influence individual’s susceptibility to breast cancer. But we found no associations regarding CDKN1B rs34330 polymorphism and this type of cancer.

Background: Osteoarthritis (OA) is the most prevalent age-related disease in the world. Chondrocytes undergo an age-dependent decline in their proliferation and synthetic capacity, which is the main cause of OA development. However, the intrinsic mechanism of chondrocyte senescence is still unclear. This study aimed to investigate the role of a novel long non-coding RNA (lncRNA), AC006064.4–201 in the regulation of chondrocyte senescence and OA progression and to elucidate the underlying molecular mechanisms. Methods: The function of AC006064.4–201 in chondrocytes was assessed using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence (IF) and β-galactosidase staining. The interaction between AC006064.4–201 and polypyrimidine tract-binding protein 1 (PTBP1), as well as cyclin-dependent kinase inhibitor 1B (CDKN1B), was evaluated using RPD-MS, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down assays. Mice models were used to investigate the role of AC006064.4–201 in post-traumatic and age-related OA in vivo. Results: Our research revealed that AC006064.4–201 was downregulated in senescent and degenerated human cartilage, which could alleviate senescence and regulate metabolism in chondrocytes. Mechanically, AC006064.4–201 directly interacts with PTBP1 and blocks the binding between PTBP1 and CDKN1B mRNA, thereby destabilizing CDKN1B mRNA and decreasing the translation of CDKN1B. The in vivo experiments were consistent with the results of the in vitro experiments. Conclusions: The AC006064.4–201/PTBP1/CDKN1B axis plays an important role in OA development and provides new molecular markers for the early diagnosis and treatment of OA in the future. Schematic diagram of AC006064.4–201 mechanism. A schematic diagram of the mechanism underlying the effect of AC006064.4–201 [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have been reported to be related to the initiation and progression of chronic obstructive pulmonary disease (COPD) by affecting the function of human bronchial epithelial cells (HBECs). Here, we aimed to investigate the function and mechanism of circ_0006872 in regulating COPD process using cigarette smoke extract (CSE)-induced 16HBEC in vitro. The results showed that circ_0006872 was increased in smokers without or with COPD, especially in smokers with COPD. Also, its expression was dose-dependently up-regulated by CSE exposure in 16HBECs. Functionally, circ_0006872 knockdown dramatically attenuated CSE-evoked proliferation arrest, apoptosis, inflammatory response and oxidative stress in 16HBECs. Mechanistically, circ_0006872/miR-485-3p/cyclin-dependent kinase inhibitor 1B (CDKN1B) formed a competitive endogenous RNA (ceRNA) network. CDKN1B was increased and miR-485-3p was decreased in COPD patients and CSE-induced 16HBECs. MiR-485-3p overexpression or CDKN1B knockdown protected 16HBEC against CSE-induced 16HBEC injury mentioned above. Moreover, rescue experiments showed that circ_0006872 regulated CSE-induced 16HBEC injury via miR-485-3p/CDKN1B axis. Circ_0006872 silencing protected against CSE-induced bronchial epithelial cell injury via miR-485-3p/CDKN1B axis, suggesting the potential application of circ_0006872 in preventing cigarette smoke-induced COPD. [ABSTRACT FROM AUTHOR]

Multiple endocrine neoplasia 4 (MEN4) is a rare multiglandular endocrine neoplasia syndrome clinically hallmarked by primary hyperparathyroidism (PHPT), pituitary adenoma (PitAd), and neuroendocrine tumors (NET), clinically overlapping MEN1. The underlying mutated gene – CDKN1B, encodes for the cell-cycle regulator p27. Possible genotype–phenotype correlations in MEN4 have not been thoroughly assessed. Prompted by the findings in three Israeli MEN4 kindreds, we performed a literature review on published and unpublished data from previously reported MEN4/CDKN1B cases. Univariate analysis analyzed time-dependent risks for developing PHPT, PitAd, or NET by variant type and position along the gene. Overall, 74 MEN4 cases were analyzed. PHPT risk was 53.4% by age 60 years (mean age at diagnosis age 50.6 ± 13.9 years), risk for PitAd was 23.2% and risk for NET was 16.2% (34.4 ± 21.4 and 52.9 ± 13.9 years, respectively). The frameshift variant p.Q107fs was the most common variant identified (4/41 (9.7%) kindreds). Patients with indels had higher risk for PHPT vs point mutations (log-rank, P = 0.029). Variants in codons 94–96 were associated with higher risk for PHPT (P < 0.001) and PitAd (P = 0.031). To conclude, MEN4 is clinically distinct from MEN1, with lower risk and older age for PHPT diagnosis. We report recurrent CDKN1B frameshift variants and possible genotype–phenotype correlations. [ABSTRACT FROM AUTHOR]

Effective treatments for prostate cancer (PCa) require further development, and previous studies have reported that PTEN and its downstream target CDKN1B are significantly downregulated in PCa cells compared with normal cells. Therefore, modulation of PTEN and CDKN1B expression might be a promising therapeutic approach for PCa treatment. Expression of PTEN and CDKN1B was verified in specimens from PCa patients and transgenic adenocarcinoma mouse prostate (TRAMP) mice. The effect of PTEN on PCa cell migration, apoptosis, and the cell cycle was analyzed in vitro using a wound-healing assay and flow cytometry. We assessed the ability of intraprostatic and intratumoral injections of recombinant adeno-associated virus (rAAV) 9 expressing Pten or Cdkn1b into TRAMP mice and a subcutaneous tumor xenograft mouse model, respectively, to inhibit PCa progression. PTEN and CDKN1B were significantly downregulated in human and mouse PCa samples, and CDKN1B expression correlated positively with PTEN expression. PTEN overexpression significantly inhibited cell migration and cell-cycle progression and promoted apoptosis in PCa cells by decreasing Ccnd1 expression and increasing that of Cdkn1b. Importantly, treatment with the rAAV9.Pten or rAAV9.Cdkn1b extended the lifespan of TRAMP mice and inhibited the growth rate of tumor xenografts by regulating downstream gene expression. Moreover, neoplasia in treated prostates was significantly diminished compared with that in control prostates, and apoptosis was markedly observed in xenografts treated with Pten or Cdkn1b. These data indicate that rAAV-based PTEN/CDKN1B delivery is promising for the development of novel therapeutics for PCa.

Simple Summary: To date, there has not been adequate research conducted on prostate cancer tumor stem cells, which play an important role in tumor recurrence, invasion, and drug resistance. In this study, we innovatively used a tumor stem cell-associated index (mRNAsi), calculated by a single-class logistic regression machine learning algorithm (OCRL), in combination with multiple databases to identify MBNL1-AS1 as a key lncRNA for prostate cancer stem cells and elucidated via in vivo and in vitro experiments. In addition, the experiments showed that the down-regulation of MBNL1-AS1 promotes the malignance of prostate cancer cell lines through the miR-221-3p/CDKN1B/C-myc axis by stimulating the stemness of tumor stem cells. This provides the basis for theoretical studies of prostate cancer and provides targets for precision therapy. The recurrence, progression, and drug resistance of prostate cancer (PC) is closely related to the cancer stem cells (CSCs). Therefore, it is necessary to find the key regulators of prostate cancer stem cells (PCSCs). Here, we analyzed the results of a single-class logistic regression machine learning algorithm (OCLR) to identify the PCSC-associated lncRNA MBNL1-AS1. The effects of MBNL1-AS1 on the stemness of CSCs was assessed using qPCR, western blot and sphere-forming assays. The role of MBNL1-AS1 in mediating the proliferation and invasion of the PC cell lines was examined using Transwell, wounding-healing, CCK-8, EdU and animal assays. Dual-luciferase and ChIRP assays were used to examine the molecular mechanism of MBNL1-AS1 in PCSCs. MBNL1-AS1 was shown to be negatively correlated with stemness index (mRNAsi), and even prognosis, tumor progression, recurrence, and drug resistance in PC patients. The knockdown of MBNL1-AS1 significantly affected the stemness of the PC cells, and subsequently their invasive and proliferative abilities. Molecular mechanism studies suggested that MBNL1-AS1 regulates CDKN1B through competitive binding to miR-221-3p, which led to the inhibition of the Wnt signaling pathway to affect PCSCs. In conclusion, our study identified MBNL1-AS1 as a key regulator of PCSCs and examined its mechanism of action in the malignant progression of PC. [ABSTRACT FROM AUTHOR]

Dysregulation of the cell cycle is an important factor in a potentially malignant oral disorder. There have not been many studies on the role of the cell cycle regulator p27 in oral non-homogenous leukoplakia. The aim of our study was to characterise the p27 protein in homogenous and non-homogenous oral leukoplakias (OL), in comparison with healthy mucosa and squamous cell carcinoma tissues. The current study included 25 patients with OL, 15 cases with oral squamous cell carcinoma, and 15 samples of healthy oral mucosa, both as comparison groups. Immunohistochemical p27 antigen expression was determined by a standard EnView imaging system. The expression level of p27 in nodular and verrucous leukoplakia was lower than in homogenous OL but higher than in erythroleukoplakia. There was a statistically significant difference (p < 0.05) between the expression of p27 in healthy mucosa and homogenous OL. There was a significantly lower amount of p27 positive cells in oral cancer than in OL (p < 0.0001); however, its intracytoplasmic presence was diagnosed. Our study proved the instability of p27 protein and its dual nature in non-homogenous OL and OSCC, and therefore, it can be used as a predictive marker for the clinical course of these conditions. [ABSTRACT FROM AUTHOR]

As a key approach to mediate cholesterol metabolism, the role of the CYP27A1/27‐HC axis in renal cell carcinoma (RCC) remains unclear. Analysis of CYP27A1 expression from public databases and metastatic cases in our center suggested that CYP27A1 was obviously downregulated in RCC tissues, and survival analysis further showed its correlation with favorable clinicopathological features and prognosis. In vitro, up and downregulation of CYP27A1 expression in RCC cell lines could definitely illustrate its anticipation involving apoptosis, proliferation, invasion, migration, and clonality. This could be achieved through upregulation of 27‐HC concentration, which mediates the activation of signaling pathways of apoptosis and cell cycle arrest. Further, recovery of CYP27A1 expression could definitely inhibit the proliferation of RCC tumors in vivo. This is the first study to explore the role of the CYP27A1/27‐HC axis in RCC. Attempts to maintain the normal function of the axis may be a potential strategy in the treatment of RCC, and the predictive value of CYP27A1 detection on the efficacy of targeted therapy in metastatic RCC is also worthy of attention. [ABSTRACT FROM AUTHOR]

Objective To construct the eukaryotic expression vector carrying the human wild-type p27 and lacking nuclear localization signal p27△NLS coding sequences，and the express them in HEK293T cells，which may contribute to investigating the different locations and roles of p27 in the cytoplasm and nucleus. Methods Total RNA was prepared from human breast cancer MCF7 cells， and cDNA was obtained by reverse transcription-polymerase chain reaction（RT- PCR）. After amplification of the p27 CDs and non-NLS fragments by PCR， full length p27WT （CDKN1B， NM_ 004064. 5）and p27△NLS coding regions were obtained. PCR products were then subcloned into the eukaryotic expression vector pCMV-Blank. After identification with bacterial PCR， double restriction enzyme digestion and sequencing， they were defined officially as pCMV-p27WT and pCMV-p27△NLS，respectively. The recombinant plasmids were transfected into HEK293T cells by electroporation. After 48 h，the levels of p27 protein in the cytoplasm and nucleus were detected by Western blotting. Results The sequencing results showed that the sequences of p27WT and p27△NLS inserted into the plasmids were both correctly consistent with that of NM_004064. 5. After transfection with pCMV-p27WT， total p27 protein expression was increased and distributed in both the cytoplasm and nucleus of HEK293T cells. After transfection with pCMV-p27 △ NLS， p27 protein was significantly increased and almost entirely localized in the cytoplasm of HEK293T cells. Conclusion The eukaryotic expression plasmids of human p27WT and p27 △ NLS coding sequences were successfully constructed and overexpressed in HEK293T cells. This research may lay a foundation for investigating the biological function of p27 in the cell cycle progression of tumor cells. [ABSTRACT FROM AUTHOR]

Background/Aim: Although genetic differences in cell-cycle control genes have been associated with cancer risk, to our knowledge, no report has specifically examined the role of gene variants in childhood acute lymphoblastic leukemia (ALL). Cyclin-dependent kinase inhibitor 1B (CDKN1B; also known as p27/KIP1) is a cell-cycle regulating gene. This study aimed at investigating the association between CDKN1B genotypes and childhood ALL risk. Materials and Methods: In 266 childhood ALL cases and 266 healthy controls, the CDKN1B rs34330 and 2066827 polymorphisms were genotyped, and the association of CDKN1B genotypes with childhood ALL risk were analyzed. Results: The genotypes of CDKN1B rs34330 and 2066827 were similarly distributed between the control and case groups (p for trend=0.8718 and 0.4030, respectively). The allelic frequency also exhibited no statistical difference (p=1.0000 and 0.6666, respectively). There was no significant interaction between CDKN1B genotypes and age or sex. Conclusion: CDKN1B genotypes were not found to be minor contributors to childhood ALL susceptibility in Taiwan. [ABSTRACT FROM AUTHOR]

Rationale: Ovarian cancer is the leading death cause in gynecological malignancies. More than 70% of the patients are diagnosed with progressing disease extending to outside the true pelvis. The 5-year survival of ovarian cancer patients remains low (about 47%) due to frequent relapses and drug resistance. Identification of markers for early diagnosis and relapse prediction could improve the outcomes of the disease.Aim: To assess relative copy number of cancer-associated genetic loci c-Myc, CDK12, CDKN1B, PRPF19, ERBB2, DDB1, GAB2, COL6A3 in the tumor cells of ovarian cancer, in order to identify potential prognostic oncomarkers in ovarian cancer patients.Materials and methods: The study included 50 women aged 27 to 70 years with ovarian cancer T1-3cN0-1M0-1, Gr. 2 (stages I—IV), who received their elective treatment in the National Medical Research Centre for Oncology in 2015 to 2019. The study was based on samples of genomic DNA from paraffinized blocks of tumor and “healthy” tissues. Relative copy numbers of 8 genetic loci (c-Myc, CDK12, CDKN1B, PRPF19, ERBB2, DDB1, GAB2, COL6A3) was assessed by RT-qPCR technique. Relative copy quantitation of a genetic locus was calculated as 2-ΔCt. The dose of the locus studied was considered equal to diploid set (2n) if RCQtumor/healthy was about 1. If RCQtumor/healthy was > 1.5 or < 0.5, then the locus dose was considered increased (≥ 3n) or decreased (≤ 1n), respectively.Results: For all genetic loci, an increase of relative copy quantitation in the ovarian tumor cells was observed compared to that in “healthy” tissues. There was a significant (р

During pancreatic development, proliferating pancreatic progenitors activate the proendocrine transcription factor neurogenin 3 (NEUROG3), exit the cell cycle, and differentiate into islet cells. The mechanisms that direct robust NEUROG3 expression within a subset of progenitor cells control the size of the endocrine population. Here we demonstrate that NEUROG3 is phosphorylated within the nucleus on serine 183, which catalyzes its hyperphosphorylation and proteosomal degradation. During progression through the progenitor cell cycle, NEUROG3 phosphorylation is driven by the actions of cyclin-dependent kinases 2 and 4/6 at G1/S cell-cycle checkpoint. Using models of mouse and human pancreas development, we show that lengthening of the G1 phase of the pancreatic progenitor cell cycle is essential for proper induction of NEUROG3 and initiation of endocrine cell differentiation. In sum, these studies demonstrate that progenitor cell-cycle G1 lengthening, through its actions on stabilization of NEUROG3, is an essential variable in normal endocrine cell genesis.

Abstract Background Although miR-190 has been reported to be related to human diseases, especially in the development and progression of cancer, its expression in human bladder cancer (BC) and potential contribution to BC remain unexplored. Methods RT-qPCR was used to verify the expression level of miR-190 and CDKN1B. Flow cytometry (FCM) assays were performed to detect cell cycle. Soft agar assay was used to measure anchorage-independent growth ability. Methylation-Specific PCR, Dual-luciferase reporter assay and Western blotting were used to elucidate the potential mechanisms involved. Results Our studies revealed that downregulation of the p27 (encoded by CDKN1B gene) protein is an important event related to miR-190, promoting the malignant transformation of bladder epithelial cells. miR-190 binds directly to CDKN1B 3’-UTR and destabilizes CDKN1B mRNA. Moreover, miR-190 downregulates TET1 by binding to the TET1 CDS region, which mediates hypermethylation of the CDKN1B promoter, thereby resulting in the downregulation of CDKN1B mRNA. These two aspects led to miR-190 inhibition of p27 protein expression in human BC cells. A more in-depth mechanistic study showed that c-Jun promotes the transcription of Talin2, the host gene of miR-190, thus upregulating the expression of miR-190 in human BC cells. Conclusions In this study, we found that miR-190 plays an important role in the development of BC. Taken together, these findings indicate that miR-190 may promote the malignant transformation of human urothelial cells by downregulating CDKN1B, which strengthens our understanding of miR-190 in regulating BC cell transformation.

Muscle atrophy is a debilitating condition with various causes; while aging is one of these causes, reduced engagement in routine muscle-strengthening activities also markedly contributes to muscle loss. Although extensive research has been conducted on microRNAs (miRNAs/miRs) and their associations with muscle atrophy, the roles played by miRNA precursors remain underexplored. The present study detected the upregulation of the miR-206 precursor in cell-free (cf)RNA from the plasma of patients at risk of sarcopenia, and in cfRNAs from the muscles of mice subjected to muscle atrophy. Additionally, a decline in the levels of the miR-6516 precursor was observed in mice with muscle atrophy. The administration of mimic-miR-6516 to mice immobilized due to injury inhibited muscle atrophy by targeting and inhibiting cyclin-dependent kinase inhibitor 1b (Cdkn1b). Based on these results, the miR-206 precursor appears to be a potential biomarker of muscle atrophy, whereas miR-6516 shows promise as a therapeutic target to alleviate muscle deterioration in patients with muscle disuse and atrophy. [ABSTRACT FROM AUTHOR]

Pre-mRNA splicing is one of the most important mechanisms in gene expression in eukaryotes, and therefore splicing inhibition affects various cellular functions. We previously reported that the potent splicing inhibitor spliceostatin A (SSA) causes cell cycle arrest at G1 and G2/M phases. Upregulation of the p27 cyclin dependent kinase inhibitor, encoded by the CDKN1B gene, is one of the reasons for G1 phase arrest caused by SSA treatment. However, the molecular mechanism of p27 upregulation by SSA remains unknown. In this study, we found that SSA treatment caused stabilization of the p27 protein and increase of CDKN1B mRNA. SSA did not affect transcription of CDKN1B gene, but stabilized CDKN1B mRNA. Finally, we revealed that the 3′ untranslated region of CDKN1B mRNA was involved in the stabilization. These results suggest that stabilization of CDKN1B mRNA is one of the reasons of upregulation of the p27 protein by SSA. • SSA upregulates CDKN1B mRNA level. • SSA stabilizes CDKN1B mRNA. • The 3′ UTR of CDKN1B mRNA is involved in the stabilization of CDKN1B mRNA by SSA. [ABSTRACT FROM AUTHOR]

Translational control is a fundamental mechanism regulating animal germ cell development. Gonadal somatic cells provide support and microenvironment for germ cell development to ensure fertility, yet the roles of translational control in gonadal somatic compartment remain largely undefined. We found that mouse homolog of conserved fly germline stem cell factor Pumilio, PUM1, is absent in oocytes of all growing follicles after the primordial follicle stage, instead, it is highly expressed in somatic compartments of ovaries. Global loss of Pum1, not oocyte-specific loss of Pum1, led to a significant reduction in follicular number and size as well as fertility. Whole-genome identification of PUM1 targets in ovarian somatic cells revealed an enrichment of cell proliferation pathway, including 48 key regulators of cell phase transition. Consistently granulosa cells proliferation is reduced and the protein expression of the PUM-bound Cell Cycle Regulators (PCCR) were altered accordingly in mutant ovaries, and specifically in granulosa cells. Increase in negative regulator expression and decrease in positive regulators in the mutant ovaries support a coordinated translational control of somatic cell cycle program via PUM proteins. Furthermore, postnatal knockdown, but not postnatal oocyte-specific loss, of Pum1 in Pum2 knockout mice reduced follicular growth and led to similar expression alteration of PCCR genes, supporting a critical role of PUM-mediated translational control in ovarian somatic cells for mammalian female fertility. Finally, expression of human PUM protein and its regulated cell cycle targets exhibited significant correlation with ovarian cancer and prognosis for cancer survival. Hence, PUMILIO-mediated cell cycle regulation represents an important mechanism in mammalian female reproduction and human cancer biology. [ABSTRACT FROM AUTHOR]

Background: The fourth type of multiple endocrine neoplasia (MEN) is known as a rare variant of MEN presenting a MEN1-like phenotype and originating from a germline mutation in CDKN1B. However, due to the small number of cases documented in the literature, the peculiar clinical features of MEN4 are still largely unknown, and clear indications about the clinical management of these patients are currently lacking. In order to widen our knowledge on MEN4 and to better typify the clinical features of this syndrome, we present two more cases of subjects with MEN4, and through a review of the current literature, we provide some possible indications on these patients' management. Case Presentation: The first report is about a man who was diagnosed with a metastatic ileal G2-NET at the age of 34. Genetic analysis revealed the mutation p.I119T (c.356T>C) of exon 1 of CDKN1B, a mutation already reported in the literature in association with early-onset pituitary adenomas. The second report is about a 76-year-old woman with a multifocal pancreatic G1-NET. Genetic analysis identified the CDKN1B mutation c.482C>G (p.S161C), described here for the first time in association with MEN4 and currently classified as a variant of uncertain significance. Both patients underwent biochemical and imaging screening for MEN1-related diseases without any pathological findings. Conclusions: According to the cases reported in the literature, hyperparathyroidism is the most common clinical feature of MEN4, followed by pituitary adenoma and neuroendocrine tumors. However, MEN4 appears to be a variant of MEN with milder clinical features and later onset. Therefore, these patients might need a different and personalized approach in clinical management and a peculiar screening and follow-up strategy. [ABSTRACT FROM AUTHOR]

Abstract In contrast to other solid tumors within the abdominal cavity, epithelial ovarian cancers (EOCs) tend to undergo peritoneal metastasis. Thus, the peritoneal immune microenvironment is crucial for EOC progression. Previous reports indicate that the main immune cells within the peritoneum are M2 macrophages, specifically tumor‐associated macrophages (TAMs). The communication between TAMs and tumor cells plays an important role in EOC development, and exosomes, acting as micro–message carriers, occupy an essential position in this process. Microarray analyses of exosomes revealed that miR‐221‐3p was enriched in M2 exosomes. Furthermore, miR‐221‐3p suppressed cyclin‐dependent kinase inhibitor 1B (CDKN1B) directly. Thus, miR‐221‐3p contributed to the proliferation and G1/S transition of EOC cells. Additionally, low levels of CDKN1B were associated with EOC progression and poor prognosis. These observations suggest that TAMs‐derived exosomal miR‐221‐3p acts as a regulator of EOC progression by targeting CDKN1B. The results of this study confirm that certain exosomal microRNAs may provide novel diagnostic biomarkers and therapeutic targets for EOC.

Abstract Background To characterize the MIAT expression in cervical cancer and elucidate its mechanistic involvement in the tumor biology of this disease. Methods The relative expression of MIAT and miR-150 was determined by real-time PCR. Cell proliferation was measured by the CCK-8 and clonogenic assay. The anchorage-independent growth was evaluated by soft agar assay. The in vivo tumor progression was assayed with xenograft mice model. The regulatory effect of miR-150 on MIAT was interrogated by luciferase reporter assay. The endogenous CNKD1B protein was detected by western blotting. Results The low expression of MIAT was characterized in cervical cancer, which associated with relatively poor prognosis. Ectopic expression of MIAT inhibited malignant growth of cervical cancer both in vitro and in vivo. Mechanistically, MIAT regulated CDKN1B expression via competition with miR-150, and miR-150-inhibition directly suppressed cervical cancer cell growth. Conclusions Our study characterized the anti-tumor property of MIAT in cervical cancer and elucidated its competitively regulation of CDKN1B with miR-150. Our data highlighted the critical role of MIAT-miR-150-CDKN1B signaling axis in cervical cancer.

BackgroundThe fourth type of multiple endocrine neoplasia (MEN) is known as a rare variant of MEN presenting a MEN1-like phenotype and originating from a germline mutation in CDKN1B. However, due to the small number of cases documented in the literature, the peculiar clinical features of MEN4 are still largely unknown, and clear indications about the clinical management of these patients are currently lacking. In order to widen our knowledge on MEN4 and to better typify the clinical features of this syndrome, we present two more cases of subjects with MEN4, and through a review of the current literature, we provide some possible indications on these patients’ management.Case PresentationThe first report is about a man who was diagnosed with a metastatic ileal G2-NET at the age of 34. Genetic analysis revealed the mutation p.I119T (c.356T>C) of exon 1 of CDKN1B, a mutation already reported in the literature in association with early-onset pituitary adenomas. The second report is about a 76-year-old woman with a multifocal pancreatic G1-NET. Genetic analysis identified the CDKN1B mutation c.482C>G (p.S161C), described here for the first time in association with MEN4 and currently classified as a variant of uncertain significance. Both patients underwent biochemical and imaging screening for MEN1-related diseases without any pathological findings.ConclusionsAccording to the cases reported in the literature, hyperparathyroidism is the most common clinical feature of MEN4, followed by pituitary adenoma and neuroendocrine tumors. However, MEN4 appears to be a variant of MEN with milder clinical features and later onset. Therefore, these patients might need a different and personalized approach in clinical management and a peculiar screening and follow-up strategy.

Posttranscriptional regulation of cancer gene expression programs plays a vital role in carcinogenesis; identifying the critical regulators of tumorigenesis and their molecular targets may provide novel strategies for cancer diagnosis and therapeutics. Highly conserved RNA-binding protein Pumilio-1 (PUM1) regulates mouse growth and cell proliferation, propelling us to examine its role in cancer. We found human PUM1 is highly expressed in a diverse group of cancer, including prostate cancer; enhanced PUM1 expression is also correlated with reduced survival among prostate cancer patients. Detailed expression analysis in twenty prostate cancer tissues showed enhanced expression of PUM1 at mRNA and protein levels. Knockdown of PUM1 reduced prostate cancer cell proliferation and colony formation, and subcutaneous injection of PUM1 knockdown cells led to reduced tumor size. Downregulation of PUM1 in prostate cancer cells consistently elevated cyclin-dependent kinase inhibitor 1B (CDKN1B) protein expression through increased translation but did not impact its mRNA level, while overexpression of PUM1 reduced CDKN1B protein level. Our finding established a critical role of PUM1 mediated translational control, particularly the PUM1-CDKN1B axis, in prostate cancer cell growth and tumorigenesis. We proposed that PUM1-CDKN1B regulatory axis may represent a novel mechanism for the loss of CDKN1B protein expression in diverse cancers and potential targets for therapeutics development. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small endogenous non‐coding RNAs that can negatively regulate the expression of their complementary mRNA targets, and have been implicated in various pathophysiological processes. In this study, we examined the effect of miR‐222‐3p on intervertebral disc degeneration (IDD). We found that expression of miR‐222‐3p was significantly higher in IDD tissues than in normal intervertebral disc tissue, and report that overexpression of miR‐222‐3p remarkably increased apoptosis and reduced proliferation of nucleus pulposus (NP) cells. In addition, miR‐222‐3p promoted secretion of matrix metalloproteinase‐3, and decreased collagen type II and aggrecan production. Cyclin‐dependent kinase inhibitor 1B (CDKN1B) was identified as a direct target of negative regulation by miR‐222‐3p in NP cells, and expression of miR‐222‐3p was found to be negatively correlated with that of CDKN1B in IDD tissue. Finally, we observed that transfection with miR‐222‐3p dramatically reduced CDKN1B expression in NP cells. In conclusion, miR‐222‐3p may be involved in IDD development, possibly through targeting CDKN1B.

Abstract Background Cisplatin resistance is a major challenge for advanced head and neck cancer (HNC). Understanding the underlying mechanisms and developing effective strategies against cisplatin resistance are highly desired in the clinic. However, how tumor stroma modulates HNC growth and chemoresistance is unclear. Results We show that cancer-associated fibroblasts (CAFs) are intrinsically resistant to cisplatin and have an active role in regulating HNC cell survival and proliferation by delivering functional miR-196a from CAFs to tumor cells via exosomes. Exosomal miR-196a then binds novel targets, CDKN1B and ING5, to endow HNC cells with cisplatin resistance. Exosome or exosomal miR-196a depletion from CAFs functionally restored HNC cisplatin sensitivity. Importantly, we found that miR-196a packaging into CAF-derived exosomes might be mediated by heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1). Moreover, we also found that high levels of plasma exosomal miR-196a are clinically correlated with poor overall survival and chemoresistance. Conclusions The present study finds that CAF-derived exosomal miR-196a confers cisplatin resistance in HNC by targeting CDKN1B and ING5, indicating miR-196a may serve as a promising predictor of and potential therapeutic target for cisplatin resistance in HNC.

Background: Although miR-190 has been reported to be related to human diseases, especially in the development and progression of cancer, its expression in human bladder cancer (BC) and potential contribution to BC remain unexplored. Methods: RT-qPCR was used to verify the expression level of miR-190 and CDKN1B. Flow cytometry (FCM) assays were performed to detect cell cycle. Soft agar assay was used to measure anchorage-independent growth ability. Methylation-Specific PCR, Dual-luciferase reporter assay and Western blotting were used to elucidate the potential mechanisms involved. Results: Our studies revealed that downregulation of the p27 (encoded by CDKN1B gene) protein is an important event related to miR-190, promoting the malignant transformation of bladder epithelial cells. miR-190 binds directly to CDKN1B 3'-UTR and destabilizes CDKN1B mRNA. Moreover, miR-190 downregulates TET1 by binding to the TET1 CDS region, which mediates hypermethylation of the CDKN1B promoter, thereby resulting in the downregulation of CDKN1B mRNA. These two aspects led to miR-190 inhibition of p27 protein expression in human BC cells. A more in-depth mechanistic study showed that c-Jun promotes the transcription of Talin2, the host gene of miR-190, thus upregulating the expression of miR-190 in human BC cells. Conclusions: In this study, we found that miR-190 plays an important role in the development of BC. Taken together, these findings indicate that miR-190 may promote the malignant transformation of human urothelial cells by downregulating CDKN1B, which strengthens our understanding of miR-190 in regulating BC cell transformation. [ABSTRACT FROM AUTHOR]

Multiple Endocrine Neoplasia type-1 (MEN1) is an autosomal dominant disorder with a combined occurrence of tumours of parathyroid glands, pancreatic islets, and anterior pituitary. About 90% of these patients carry mutations in the MEN1 gene, though the spectrum is not well defined in India. Forty clinically suspected cases of MEN1 were enrolled prospectively over six years; 32 patients (23 index-cases and nine affected relatives) with≥2 classical endocrine tumours of MEN1 were considered definite, and eight were categorised as 'MEN1-like'. Details of their clinical presentation, treatment and mutational analysis including MEN1 gene, 3′ and 5′ untranslated regions (UTR) of MEN1, CDKN1B, and CaSR genes were collated. Asymptomatic first-degree relatives were also screened. Among the 32 definite MEN1 patients, all had primary hyperparathyroidism, 22 (68.7%) had gastroentero-pancreatic neuroendocrine tumours, and 21 (66%) had pituitary adenoma. Of the 23 definite index-cases, 13 (56.5%) carried mutations in the MEN1 gene. Five of nine affected first-degree relatives (55.5%), and four of 10 asymptomatic relatives (40%) also had MEN1 mutations. Seven of 10 MEN1 mutation-negative definite index-cases harboured p.V109G polymorphism in the CDKN1B gene. All eight MEN1-like cases were negative for mutations and large deletions in MEN1, mutations in 3′ and 5′ UTR of MEN1, CaSR and CDKN1B genes. The study has helped to clearly document the pattern of mutations among Indian MEN1 patients. However, the absence of MEN1 mutation in ~44% of cases and the presence of p.V109G polymorphism in CDKN1B gene raise the question whether such polymorphisms could independently contribute to pathogenesis. [ABSTRACT FROM AUTHOR]

Glomerular hypertrophy is an early morphological alteration in diabetic nephropathy. Cyclin-Dependent Kinases have been shown to be required for high glucose (HG)-induced hypertrophy; however, the upstream regulators of CDKN1B in glomerular hypertrophy remain unclear. Herein we describe a novel pathway in which Long noncoding RNA (lncRNA) NEAT1 regulates the progression of mesangial cell hypertrophy via a competing endogenous RNA (ceRNA) mechanism. Real-time PCR was performed to detect the relative NEAT1 and miR-222-3p expressions and further confirmed the relationship between NEAT1 and miR-222-3p. Cell cycle was evaluated by flow cytometry. The related mechanisms were explored by Western blot, RNA immunoprecipitation and chromatin immunoprecipitation assay. We show that NEAT1 forms double stranded RNA (dsRNA) with miR-222-3p, thus limiting miR-222-3p’s binding with CDKN1B. This release of CDKN1B mRNA leads to elevated CDKN1B protein expression, resulting in hypertrophy. In addition, we demonstrated that STAT3 which is activated by HG induces the transcription of NEAT1 by binding to its promoter. Our findings underscore an unexpected role of lncRNAs on gene regulation and introduce a new mode of proliferation regulation in mesangial cells.

The CDKN1B gene, encoding for the CDK inhibitor p27kip1, is mutated in defined human cancer subtypes, including breast, prostate carcinomas and small intestine neuroendocrine tumors. Lessons learned from small intestine neuroendocrine tumors suggest that CDKN1B mutations could be subclonal, raising the question of whether a deeper sequencing approach could lead to the identification of higher numbers of patients with mutations. Here, we addressed this question and analyzed human cancer biopsies from breast (n = 396), ovarian (n = 110) and head and neck squamous carcinoma (n = 202) patients, using an ultra‐deep sequencing approach. Notwithstanding this effort, the mutation rate of CDKN1B remained substantially aligned with values from the literature, showing that essentially only hormone receptor‐positive breast cancer displayed CDKN1B mutations in a relevant number of cases (3%). However, the analysis of copy number variation showed that another fraction of luminal breast cancer displayed loss (8%) or gain (6%) of the CDKN1B gene, further reinforcing the idea that the function of p27kip1 is important in this type of tumor. Intriguingly, an enrichment for CDKN1B alterations was found in samples from premenopausal luminal breast cancer patients (n = 227, 4%) and in circulating cell‐free DNA from metastatic luminal breast cancer patients (n = 59, 8.5%), suggesting that CDKN1B alterations could correlate with tumor aggressiveness and/or occur later during disease progression. Notably, many of the identified somatic mutations resulted in p27kip1 protein truncation, leading to loss of most of the protein or of its C‐terminal domain. Using a gene‐editing approach in a luminal breast cancer cell line, MCF‐7, we observed that the expression of p27kip1 truncating mutants that lose the C‐terminal domains failed to rescue most of the phenotypes induced by CDKN1B gene knockout, indicating that the functions retained by the C‐terminal portion are critical for its role as an oncosuppressor, at least in luminal breast cancer. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Multiple endocrine neoplasia (MEN) is a group of syndromes with a genetic predisposition to the appearance of endocrine tumors, and shows autosomal dominant transmission. The advent of molecular genetics has led to improvements in the management of MEN in terms of diagnosis, prognosis and therapy. The genetics of MEN is the subject of regular updates, which will be presented throughout this paper. MEN1, the first to be described, is associated with the MEN1 gene. MEN1 is well known in terms of the observed phenotype, with genetic analysis being conclusive in 90% of patients with a typical phenotype, but is negative in around 10% of families with MEN1. Improvement in analysis techniques and the identification of other genes responsable for phenocopies allows the resolution of some, but not all, cases, notably non-familial forms suspected to be fortuitous assocations with tumors. MEN4 is a rare phenocopy of MEN1 linked to constitutional mutations in the CDKN1B gene. Though it closely resembles the phenotype of MEN1, published data suggests the appearance of tumors is later and less frequent in MEN4. MEN2, which results from mutations in the RET oncogene, shows a strong genotype-phenotype correlation. This correlation is particularly evident in the major manifestation of MEN2, medullary thyroid carcinoma (MTC), in which disease aggressiveness is dependent on the pathogenic variant of RET. However, recent studies cast doubt on this correlation between MTC and pathogenic variant. Lastly, the recent description of families carrying a mutation in MAX, which is known to predispose to the development of pheochromocytoma and paraganglioma, and presents a phenotypic spectrum that evokes MEN, suggests the existence of another syndrome, MEN5., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background/Aims: MiRNAs are involved in phenotype modulation of neural cells after peripheral nerve injury. However, the roles of miRNAs on the survival of dorsal root ganglion (DRG) neurons have not yet been fully understood. Methods: In this study, the expression of miR-142-3p was measured in rat DRGs (L4-L6) during the initial 24 hours post sciatic nerve transection by microarray profiling and quantitative PCR. The functional assays including the cell viability, colony formation, cell cycle and apoptosis assays were performed in miR-142-3p mimic or inhibitor transfected cell lines. Results: MiR-142-3p was identified to be siginificantly upregulated in rat DRGs (L4-L6) during the initial 24 hours post sciatic nerve transection. MiR-142-3p mimic enhanced cell viability by promoting cell cycle and inhibiting cell apoptosis in cultured DRG neurons. In addition, cyclin-dependent kinase inhibitor 1B (CDKN1B, also known as p27/Kip1) and tissue inhibitor of metalloproteinase 3 (TIMP3) were identified as targets of miR-142-3p. Furthermore, knockdown of CDKN1B or TIMP3 by specific siRNAs could reverse the effect of miR-142-3p. Conclusions: In the conclusion, the results showed that miR-142-3p could promote neuronal cell cycle and inhibit apoptosis at least partially through suppressing CDKN1B and TIMP3 after peripheral nerve injury.

MicroRNAs (miRNAs) exert critical roles in the majority of biological and pathological processes. Recent studies have associated miR-150 with a number of different cancer types. However, little is known about miR-150 targets in cervical cancer. In the present study, the HeLa human cervical cancer cell line was transfected with hsa-miR-150-5p mimics, hsa-miR-150-5p inhibitors or miRNA controls. miR-150 was predicted to bind the 3'untranslated region (3'UTR) of the CDKN1B gene, which encodes the cyclin-dependent kinase inhibitor 1B (p27Kip1). The direct binding between miR-150 and the 3'UTR of CDKN1B was confirmed using dual-luciferase reporter assays. The effects of miR-150 on CDKN1B mRNA expression, p27Kip1 protein expression, cell cycle and cell proliferation were determined using reverse-transcription quantitative PCR, western blot analysis, flow cytometry and WST-8 assays, respectively. miR-150 was demonstrated to directly target the 3'UTR of CDKN1B in transfected HeLa cells. The expression of CDKN1B mRNA and p27Kip1 protein was reduced by miR-150 mimics, and increased by miR-150 inhibitors. Moreover, the overexpression of miR-150 promoted cell cycle progression from the G0/G1 to the S phase and led to a significant increase in HeLa cell proliferation. The results of the present study indicated that miR-150 promotes HeLa cell cycle progression and proliferation via the suppression of p27Kip1 expression. [ABSTRACT FROM AUTHOR]

Background/Aims: To analyze the clinical significance of miR-196b expression in ovarian cancer and predict the function and possible mechanism of miR-196b. Methods: Both Kaplan–Meier (K-M) and Cox proportional hazards regression model were used to analyze the prognostic factors of patients with ovarian cancer. MiR196-b was modulated in ovarian cancer cells, and the cell viability, cell cycle, and cell cycle-related gene expression were analyzed. The target genes of miR-196b were then predicted and checked the relationship between the target genes. Results: MiR-196b was an independent risk factor, while high expression of miR-196b was associated with poor prognosis of ovarian cancer. MiR-196b overexpression increased cancer cell proliferation. Cdkn1b, as one of the targets of miR-196b, was related to cell viability and mitosis. Conclusion: High expression of miR-196b was significantly associated with poor prognosis of the patients with ovarian cancer. MiR-196b could increase the cell proliferation of ovarian cancer by modulating Cdkn1b expression. [ABSTRACT FROM AUTHOR]