Biology Direct最新文献

Background: MicroRNAs (miRNAs) are critical regulators of cancer progression, prompting our investigation into the specific function of miR-630 in pancreatic cancer stem cells (PCSCs). Analysis of miRNA and mRNA expression data in PCSCs revealed downregulation of miR-630 and upregulation of PRKCI, implying a potential role for miR-630 in PCSC function and tumorigenicity.

Results: Functional assays confirmed that miR-630 directly targets PRKCI, leading to the suppression of the Hedgehog signaling pathway and consequent inhibition of PCSC self-renewal and tumorigenicity in murine models. This study unveiled the modulation of the PRKCI-Hedgehog signaling axis by miR-630, highlighting its promising therapeutic potential for pancreatic cancer (PC) treatment.

Conclusions: MiR-630 emerges as a pivotal regulator in PCSC biology, opening up new avenues for targeted interventions in PC. The inhibitory effect of miR-630 on PCSC behavior underscores its potential as a valuable therapeutic target, offering insights into innovative treatment strategies for this challenging disease.

Chlamydomonas reinhardtii, a model organism for unicellular green microalgae, is widely used in basic and applied research. Nonetheless, proceeding towards synthetic biology requires a full set of manipulation techniques for inserting, removing, or editing genes. Despite recent advancements in CRISPR/Cas9, still significant limitations in producing gene knock-outs are standing, including (i) unsatisfactory genome editing (GE) efficiency and (ii) uncontrolled DNA random insertion of antibiotic resistance markers. Thus, obtaining efficient gene targeting without using marker genes is instrumental in developing a pipeline for efficient engineering of strains for biotechnological applications. We developed an efficient DNA-free gene disruption strategy, relying on phenotypical identification of mutants, to (i) precisely determine its efficiency compared to marker-relying approaches and (ii) establish a new DNA-free editing tool. This study found that classical CRISPR Cas9-based GE for gene disruption in Chlamydomonas reinhardtii is mainly limited by DNA integration. With respect to previous results achieved on synchronized cell populations, we succeeded in increasing the GE efficiency of single gene targeting by about 200 times and up to 270 times by applying phosphate starvation. Moreover, we determined the efficiency of multiplex simultaneous gene disruption by using an additional gene target whose knock-out did not lead to a visible phenotype, achieving a co-targeting efficiency of 22%. These results expand the toolset of GE techniques and, additionally, lead the way to future strategies to generate complex genotypes or to functionally investigate gene families. Furthermore, the approach provides new perspectives on how GE can be applied to (non-) model microalgae species, targeting groups of candidate genes of high interest for basic research and biotechnological applications.

Introduction: Dysregulated androgen receptor (AR) activity is central to various diseases, particularly prostate cancer (PCa), in which it drives tumour initiation and progression. Consequently, antagonising AR activity via anti-androgens is an indispensable treatment option for metastatic PCa. However, despite initial tumour remission, drug resistance occurs. Therefore, the AR signalling pathway has been intensively investigated. However, the role of AR protein stability in AR signalling and therapy resistance has not yet been deciphered. Therefore, this study aimed to investigate the role of AR protein changes in transactivity and assess its mechanism as a possible target in PCa.

Methods: LNCaP, C4-2, and 22Rv1 cells were treated with R1881, enzalutamide, cycloheximide, and Rocaglamide. Mass spectrometry analyses were performed on LNCaP cells to identify the pathways enriched by the treatments. Western blotting was performed to investigate AR protein levels and localisation changes. Changes in AR transactivity were determined by qPCR.

Results: Mass spectrometry analyses were performed on LNCaP cells to decipher the molecular mechanisms underlying androgen- and antiandrogen-induced alterations in the AR protein. Pathway analysis revealed the enrichment of proteins involved in different pathways that regulate translation. Translational and proteasome inhibitor experiments revealed that these AR protein changes were attributable to modifications in translational activity. Interestingly, the effects on AR protein levels in castration-resistant PCa (CRPC) cells C4-2 or enzalutamide-resistant cells 22Rv1 were less prominent and non-existent. This outcome was similarly observed in the alteration of AR transactivation, which was suppressed in hormone-sensitive prostate cancer (HSPC) LNCaP cells by translational inhibition, akin to the effect of enzalutamide. In contrast, treatment-resistant cell lines showed only a slight change in AR transcription.

Conclusion: This study suggests that in HSPC, AR activation triggers a signalling cascade that increases AR protein levels by enhancing its translation rate, thereby amplifying AR activity. However, this mechanism appears to be dysregulated in castration-resistant PCa cells.

Background: Biosynthesis of 17β-estradiol (E2) is a crucial ovarian function in mammals, which is essential for follicular development and pregnancy outcome. Exploring the epigenetic regulation of E2 synthesis is beneficial for maintaining ovary health and the optimal reproductive traits. NORFA is the first validated sow fertility-associated long non-coding RNA (lncRNA). However, its role on steroidogenesis is elusive. The aim of this study is to investigate the regulation and underlying mechanism of NORFA to E2 synthesis in sow granulosa cells (GCs).

Results: Through Pearson correlation analysis and comparative detection, we found that NORFA expression was positively correlated with the levels of pregnenolone (PREG) and E2 in follicles, which also exhibited similar alteration patterns during follicular atresia. ELISA was conducted and indicated for the first time that NORFA induced the synthesis of PREG and E2 in sow GCs in a dose- and time-dependent manner. RNA-seq, GSEA and quantitative analyses results validated that CYP11A1, the coding gene of P450SCC which is the first step rate-limiting enzyme of E2 synthesis, was a positive functional target of NORFA. Mechanistically, NORFA promotes SF-1 expression by stabilizing NR5A1 mRNA through directly interacting with its 3'-UTR, and also tethers SF-1 to shuttle into nucleus. Additionally, SF-1 in the nucleus activates CYP11A1 transcription by directly binding to its promoter, which ultimately induces E2 synthesis and inhibits GC apoptosis.

Conclusion: Our findings highlight that NORFA, a multifunctional lncRNA, induces E2 synthesis and inhibits GC apoptosis through the SF-1/CYP11A1 axis in a ceRNA-independent manner, which provide valuable clues and potential targets for follicular atresia inhibition and female fertility improvement.

The expression of TRIM47, a member of the TRIM protein and E3 ubiquitin ligase families, is elevated in various cancers, such as non-small cell lung cancer and colorectal cancer, and is linked to poor prognosis. This study aimed to investigate the role of TRIM47 in gastric cancer development. Using The Cancer Genome Atlas-Stomach Adenocarcinoma (TCGA-STAD) dataset and analysis of 20 patient samples from our center, TRIM47 was found to be significantly up-regulated in gastric cancer tissues and associated with advanced N-stage and poor prognosis. We constructed stable TRIM47 knockdown and overexpressing gastric cancer cell lines. CCK8, EDU, colony formation, wound healing, and Transwell tests were used to evaluate the effects on cell proliferation, invasion, and migration. The results showed that TRIM47 knockdown inhibited the proliferation, migration and invasion of gastric cancer cells, while TRIM47 overexpression promoted these behaviors. These results were further confirmed in vivo. In the mechanism part, we found that TRIM47 interacts with CYLD protein. Moreover, TRIM47 promotes K48-linked ubiquitination, leading to the degradation of CYLD by the proteasome, thereby activating the NF-κB pathway and regulating the biological behavior of gastric cancer cells. Taken together, our study demonstrated that TRIM47 is involved in the proliferation and metastasis of gastric cancer through the CYLD/NF-κB pathway.

Background: Accurately identifying effective biomarkers and translating them into clinical practice have significant implications for improving clinical outcomes in hepatocellular carcinoma (HCC). In this study, our objective is to explore appropriate methods to improve the accuracy of biomarker identification and investigate their clinical value.

Methods: Concentrating on the N6-methyladenosine (m6A) modification regulators, we utilized dozens of multi-omics HCC datasets to analyze the expression patterns and genetic features of m6A regulators. Through the integration of big data analysis with function experiments, we have redefined the biological roles of m6A regulators in HCC. Based on the key regulators, we constructed m6A risk models and explored their clinical value in estimating prognosis and guiding personalized therapy for HCC.

Results: Most m6A regulators exhibit abnormal expression in HCC, and their expression is influenced by copy number variations (CNV) and DNA methylation. Large-scale data analysis has revealed the biological roles of many key m6A regulators, and these findings are well consistent with experimental results. The m6A risk models offer significant prognostic value. Moreover, they assist in reassessing the therapeutic potential of drugs such as sorafenib, gemcitabine, CTLA4 and PD1 blockers in HCC.

Conclusions: Our findings suggest that the mutual validation of big data analysis and functional experiments may facilitate the precise identification and definition of biomarkers, and our m6A risk models may have the potential to guide personalized chemotherapy, targeted treatment, and immunotherapy decisions in HCC.

Background: Centrosomal protein of 55 kDa (CEP55) overexpression has been linked to tumor stage, aggressiveness of the tumor, poor prognosis, and metastasis. This study aims to elucidate the action of CEP55 in ovarian cancer (OC) and the regulation by the alpha-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5)/Forkhead box protein P2 (FOXP2) axis.

Methods: Differentially expressed genes in OC were identified using in silico identification, followed by prognostic value assessment. Lentiviral vectors were constructed to downregulate CEP55 in OC cells, and colony formation, EdU, TUNEL, flow cytometry, Transwell assays, and Phalloidin staining were conducted. Transcription factors regulating CEP55 were predicted and verified, and rescue experiments were performed. The effect of ALKBH5-mediated demethylation on FOXP2 mRNA stability and OC cell cycle and EMT were analyzed.

Results: High expression of CEP55 in OC was linked to unsatisfactory prognosis of patients. Knockdown of CEP55 repressed proliferation, invasiveness, and epithelial-mesenchymal transition (EMT) while inducing apoptosis and cell cycle arrest in OC cells. FOXP2 bound to the promoter of CEP55 to repress CEP55 transcription. FOXP2 regulated transcriptional repression of CEP55 to impede the malignant progression of OC and inhibit tumor metastasis. ALKBH5-mediated demethylation modification induced mRNA degradation of FOXP2. Knockdown of ALKBH5 induced cell cycle arrest and inhibited EMT in OC cells.

Conclusions: ALKBH5 hinders FOXP2-mediated transcriptional repression of CEP55 to promote the malignant progression of OC via cell cycle and EMT.

Background: The growing body of evidence suggests that RNA-binding proteins (RBPs) have an important function in cancer biology. This research characterizes the expression status of fragile X-related protein 1 (FXR1) in esophageal cancer (ESCA) cell lines and understands its mechanistic importance in ESCA tumor biology.

Methods: The role of FXR1, PDZK1IP1, and ATOH8 in the malignant biological behaviors of ESCA cells was investigated using in-vitro and in-vivo experiments.

Results: FXR1 was aberrantly overexpressed at both the transcript and protein levels in ESCA cells. Deficiency of FXR1 in ESCA cells was associated with decreased cell proliferation, viability and compromised cell migration compared to the control group. In addition, the inhibition of FXR1 leads to the promotion of apoptosis and cell cycle arrest in ESCA cells. Furthermore, FXR1 knockdown stabilizes senescence markers, promoting cellular senescence and decreasing cancer growth. Mechanistically, FXR1 negatively regulated PDZK1IP1 or ATOH8 transcripts by promoting mRNA degradation via direct interaction with its 3'UTR. PDZK1IP1 or ATOH8 overexpression predominantly inhibited the tumor-promotive phenotype in FXR1-overexpressed cells. Furthermore, FXR1 inhibition and PDZK1IP1 or ATOH8 overexpression in combination with FXR1-overexpressed cells significantly decreased xenograft tumor formation and enhanced nude mouse survival without causing apparent toxicity (P < 0.01). In the FXR1 knockdown group, the tumor weight of mice decreased by 80% compared to the control group (p < 0.01).

Conclusions: Our results demonstrate FXR1's oncogenic involvement in ESCA cell lines, suggesting that FXR1 may be implicated in ESCA development by regulating the stability of PDZK1IP1 and ATOH8 mRNAs. For the first time, our findings emphasize the importance of FXR1-PDZK1IP1 and -ATOH8 functional modules in the development of ESCA, which might have potential diagnostic or therapeutic implications.

Background: The role of the RING finger protein superfamily in carcinogenesis has been widely studied, but one member of this family, RNF19A, has not yet been thoroughly explored in bladder cancer (BCa).

Methods: The expression levels of RNF19A in BCa samples and cell lines were analysed through data mining of public resources and further experiments. BCa cells in which RNF19A was stably overexpressed or knocked down were generated through lentivirus infection. The effects of RNF19A on cell proliferation, migration, and invasion were explored by performing a series of in vitro experiments, including CCK-8, colony formation, wound healing, and Transwell invasion assays. Using bioinformatics methods and multiple experiments, including western blot, qRT‒PCR, immunoprecipitation, cycloheximide, ubiquitination, and rescue assays, the mechanism underlying the effect of RNF19A on the progression of BCa was investigated.

Results: Here, we found that RNF19A expression was reduced in BCa samples and cell lines and that lower RNF19A expression predicted shorter overall survival of BCa patients. Functionally, forced expression of RNF19A suppressed BCa cell proliferation, migration, and invasion by inactivating the AKT/mTOR signalling pathway, whereas silencing RNF19A had the opposite effects. Mechanistically, RNF19A could directly interact with ILK and promote its ubiquitination and degradation. Rescue experiments revealed that forced ILK expression partially rescued the decreased phosphorylation of AKT, mTOR, and S6K1 caused by RNF19A overexpression and that the increased levels of the p-AKT, p-mTOR, and p-S6K1 proteins induced by RNF19A knockdown were eliminated after silencing ILK. Similarly, the effects of RNF19A overexpression or knockdown on the phenotypes of cell proliferation, migration, and invasion could also be restored by forced or decreased ILK expression.

Conclusions: RNF19A suppressed the proliferation, migration, and invasion abilities of BCa cells by regulating ILK ubiquitination and inactivating the AKT/mTOR signalling pathway. RNF19A might be a potential prognostic biomarker and promising therapeutic target for BCa.

Background: Identifying therapeutic inhibitors of crucial enzymes involved in the peptidoglycan biosynthesis pathway is pivotal for developing new treatments against multidrug-resistant Enterococcus faecalis V583. MurM, an essential enzyme in this pathway, plays a significant role in the bacterium's cell wall synthesis, making it an attractive druggable target for novel antimicrobial strategies. This study explored the potential of natural compounds as inhibitors of MurM, aiming to discover promising drug candidates that could serve as the foundation for future therapeutic development.

Methods: The three-dimensional structure of MurM was predicted, optimized, and its binding pocket was analyzed by comparing it with related structures. Over 4,70,000 natural compounds from the COCONUT database were subjected to virtual high-throughput screening (vHTS). The top lead candidates were selected based on their Lipinski's profile, ADME profile, toxicity profile, estimated binding free energy (ΔG) and estimated inhibition constant (Ki). Interaction pattern analysis was used to evaluate the non-covalent interactions between the inhibitors and key residues in MurM's binding pocket. Molecular dynamics simulations were performed over 300 ns to assess the structural stability and impact of these inhibitors on MurM's enzyme.

Results: Three lead compounds-CNP0056520, CNP0126952, and CNP0248480-were identified and prioritized with estimated ΔG ranging from - 9.35 to -7.9 kcal/mol. Molecular dynamics simulations revealed minimal impact on MurM's overall structure and dynamics, with the candidate inhibitors forming stable protein-ligand complexes. These interactions were supported by several non-covalent interactions between the candidate inhibitors and key residues within MurM's binding pocket.

Conclusion: These findings suggest that the identified natural product candidates could serve as promising inhibitors of MurM, potentially leading to novel therapeutics targeting cell wall biosynthesis in multidrug-resistant E. faecalis.