The incidence of aggressive neuroendocrine prostate cancers (NEPC) related to androgen-deprivation therapy (ADT) is rising. NEPC is still poorly understood, such as its neuroendocrine differentiation (NED) and angiogenic phenotypes. Here we reveal that NED and angiogenesis are molecularly connected through EZH2 (enhancer of zeste homolog 2). NED and angiogenesis are both regulated by ADT-activated CREB (cAMP response element-binding protein) that in turn enhances EZH2 activity. We also uncover anti-angiogenic factor TSP1 (thrombospondin-1, THBS1) as a direct target of EZH2 epigenetic repression. TSP1 is downregulated in advanced prostate cancer patient samples and negatively correlates with NE markers and EZH2. Furthermore, castration activates the CREB/EZH2 axis, concordantly affecting TSP1, angiogenesis and NE phenotypes in tumor xenografts. Notably, repressing CREB inhibits the CREB/EZH2 axis, tumor growth, NED, and angiogenesis in vivo. Taken together, we elucidate a new critical pathway, consisting of CREB/EZH2/TSP1, underlying ADT-enhanced NED and angiogenesis during prostate cancer progression.
Histone lactylation has been reported to involve in tumorigenesis and development. However, its biological regulatory mechanism in endometrial carcinoma (EC) is yet to be reported in detail. In the present study, we evaluated the modification levels of global lactylation in EC tissues by immunohistochemistry and western blot, and it was elevated. The non-metabolizable glucose analog 2-deoxy-d-glucose (2-DG) and oxamate treatment could decrease the level of lactylation so as to inhibit the proliferation and migration ability, induce apoptosis significantly, and arrest the cell cycle of EC cells. Mechanically, histone lactylation stimulated USP39 expression to promote tumor progression. Moreover, USP39 activated PI3K/AKT/HIF-1α signaling pathway via interacting with and stabilizing PGK1 to stimulate glycolysis. The results of present study suggest that histone lactylation plays an important role in the progression of EC by promoting the malignant biological behavior of EC cells, thus providing insights into potential therapeutic strategies for endometrial cancer.
CD147/EMMPRIN (extracellular matrix metalloproteinase inducer) plays an important role in tumor progression and a number of studies have suggested that it is an indicator of tumor prognosis. This current meta-analysis systematically reevaluated the predictive potential of CD147/EMMPRIN in various cancers. We searched PubMed and Embase databases to screen the literature. Fixed-effect and random-effect meta-analytical techniques were used to correlate CD147 expression with outcome measures. A total of 53 studies that included 68 datasets were eligible for inclusion in the final analysis. We found a significant association between CD147/EMMPRIN overexpression and adverse tumor outcomes, such as overall survival, disease-specific survival, progression-free survival, metastasis-free survival or recurrence-free survival, irrespective of the model analysis. In addition, CD147/EMMPRIN overexpression predicted a high risk for chemotherapy drugs resistance. CD147/EMMPRIN is a central player in tumor progression and predicts a poor prognosis, including in patients who have received chemo-radiotherapy. Our results provide the evidence that CD147/EMMPRIN could be a potential therapeutic target for cancers.
Ubiquitin-conjugating enzyme E2C (UBE2C) plays important roles in tumor progression; nevertheless, its function in endometrial cancer remains unclear. This study elucidated the impact of UBE2C on endometrial cancer and its underlying mechanism. Human endometrial cancer and normal endometrial tissues were acquired from patients at Wuhan Union Hospital and UBE2C expression was detected by Western blotting and qRT-PCR. Endometrial cancer cells were transfected with a UBE2C overexpression plasmid or UBE2C-specific short hairpin RNA (shRNA) to up- or downregulate UBE2C expression, respectively. CCK8 and transwell assays were applied to assess the effects of UBE2C on cell proliferation, migration, and invasion. We found a significant elevation of UBE2C expression in patients with endometrial cancer, and that UBE2C upregulation was associated with advanced histologic grade, FIGO stage, recurrence, and shorter overall survival. UBE2C knockdown inhibited endometrial cancer cell proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT), whereas UBE2C overexpression exerted the opposite effects. UBE2C downregulation increased p53 and its downstream p21 expression, with p53 overexpression reversing the EMT-promoting effects of UBE2C. UBE2C enhanced p53 ubiquitination to facilitate its degradation in endometrial cancer cells. Estradiol (E2) induced UBE2C expression via estrogen receptor α, which binds directly to the UBE2C promoter element. Silencing of UBE2C inhibited E2-promoted migration, invasion, and EMT in vitro and in vivo. Implications: UBE2C-mediated tumor EMT promotion by estrogen is a novel mechanism for the progression of estrogen-induced endometrial cancer, which could offer new biomarkers for diagnosis and therapy of endometrial cancer in the future.
Endometrial cancer (EC) is one of the most common gynecological cancers. Ferroptosis is a newly identified form of cell death characterized by iron-dependent lipid peroxide accumulation. Circular RNAs (circRNAs) have emerged as critical regulators for cancer development. However, circRNA-mediated modulation of ferroptosis in EC is yet to be clarified. In this study, we found that circRAPGEF5 expression was elevated in EC tissues compared to the normal endometrial tissues. In vitro and in vivo functional analysis demonstrated that circRAPGEF5 facilitates rapid proliferation of EC cells. RNA binding protein fox-1 homolog 2 (RBFOX2), a splicing regulator, was identified as the protein interacts with circRAPGEF5. Further studies revealed that circRAPGEF5 can bind to the Fox-1 C-terminal domain of RBFOX2 and induces specific exon exclusion of TFRC through obstructing the binding of RBFOX2 to pre-mRNA. As a result, elevated levels of circRAPGEF5 lead to ferroptosis resistance via the decreased labile iron pool and attenuated lipid peroxide production in EC cells. Additionally, a series of gain- and loss-of-function experiments demonstrated that knocking down or overexpressing RBFOX2 reversed the effects of knocking down or overexpressing circRAPGEF5 in EC cells. Finally, it is revealed that circRAPGEF5 promote the formation of TFRC with exon-4 skipping and confer ferroptosis resistance in EC cells through the interaction with RBFOX2. Collectively, these findings provide new insight into the molecular mechanism in which circRNAs mediate mediates ferroptosis via modulating alternative splicing, and circRAPGEF5/RBFOX2 splicing axis could be a promising therapeutic target for treating EC.
Although CRISPR-Cas12a [clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 12a] combining pre-amplification technology has the advantage of high sensitivity in biosensing, its generality and specificity are insufficient, which greatly restrains its application range. Here, we discovered a new targeting substrate for LbaCas12a (Lachnospiraceae bacterium Cas12a), namely double-stranded DNA (dsDNA) with a sticky-end region (PAM−SE+ dsDNA). We discovered that CRISPR-Cas12a had special enzymatic properties for this substrate DNA, including the ability to recognize and cleave it without needing a protospacer adjacent motif (PAM) sequence and a high sensitivity to single-base mismatches in that substrate. Further mechanism studies revealed that guide RNA (gRNA) formed a triple-stranded flap structure with the substrate dsDNA. We also discovered the property of low-temperature activation of CRISPR-Cas12a and, by coupling with the unique DNA hybridization kinetics at low temperature, we constructed a complete workflow for low-abundance point mutation detection in real samples, which was fast, convenient and free of single-stranded DNA (ssDNA) transformation. The detection limits were 0.005–0.01% for synthesized strands and 0.01–0.05% for plasmid genomic DNA, and the mutation abundances provided by our system for 28 clinical samples were in accordance with next-generation sequencing results. We believe that our work not only reveals novel information about the target recognition mechanism of the CRISPR-Cas12a system, but also greatly broadens its application scenarios.