Inhibition of UBE2N-dependent CDK6 protein degradation by miR-934 promotes human bladder cancer cell growth

TAF15 inhibits p53 nucleus translocation and promotes HCC cell 5-FU resistance via post-transcriptional regulation of UBE2N

Chemotherapy resistance is an important factor responsible for the low 5-year survival rate of hepatocellular carcinoma (HCC) patients. Ubiquitin-conjugating enzyme E2N (UBE2N) is a cancer-associated ubiquitin-conjugating enzyme that is expressed in HCC tissues, and its high expression is associated with a poor prognosis. This study explored the role played by UBE2N in development of 5-fluorouracil (5-FU) resistance in HCC cells. Three HCC cell lines (HepG2 [p53 wild type], Huh7 [p53 point mutant type], Hep3B [p53 non-expression type]), and one normal liver cell line (MIHA) were used in our present study. The IC50 value of 5-FU was determined using a cell counting kit-8 (CCK-8) assay. Cell viability was assessed by colony formation assays. TUNEL assays and flow cytometry were used to analyze cell apoptosis. RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to confirm the binding relationship between UBE2N mRNA and TAF15 protein. Our results showed that TAF15 and UBE2N were highly expressed in HCC cells. UBE2N inhibited the translocation of p53 protein into the cell nucleus to increase 5-FU resistance, as reflected by an increased IC50 value, an increase in cell viability, and a reduction in cell apoptosis. Overexpression of p53 reduced 5-FU resistance, but that effect could be reversed by UBE2N overexpression. TAF15 protein bound to and stabilized UBE2N mRNA, thereby inhibiting p53 translocation into the nucleus and promoting 5-FU resistance in HCC cells. Collectively, our present study identified a novel mechanism by which TAF15/UBE2N regulates p53 distribution to increase 5-FU resistance. Our results also suggest potential therapeutic strategies for treating HCC.

SelK promotes glioblastoma cell proliferation by inhibiting β-TrCP1 mediated ubiquitin-dependent degradation of CDK4

BACKGROUND

Glioblastoma (GB) is recognized as one of the most aggressive brain tumors, with a median survival of 14.6 months. However, there are still some patients whose survival time was greater than 3 years, and the biological reasons behind this clinical phenomenon arouse our research interests. By conducting proteomic analysis on tumor tissues obtained from GB patients who survived over 3 years compared to those who survived less than 1 year, we identified a significant upregulation of SelK in patients with shorter survival times. Therefore, we hypothesized that SelK may be an important indicator related to the occurrence and progression of GBM.

METHODS

Proteomics and immunohistochemistry from GB patients were analyzed to investigate the correlation between SelK and clinical prognosis. Cellular phenotypes were evaluated by cell cycle analysis, cell viability assays, and xenograft models. Immunoblots and co-immunoprecipitation were conducted to verify SelK-mediated ubiquitin-dependent degradation of CDK4.

RESULTS

SelK was found to be significantly upregulated in GB samples from short-term survivors (≤ 1 year) compared to those from long-term survivors (≥ 3 years), and its expression levels were negatively correlated with clinical prognosis. Knocking down of SelK expression reduced GB cell viability, induced G0/G1 phase arrest, and impaired the growth of transplanted glioma cells in nude mice. Down-regulation of SelK-induced ER stress leads to a reduction in the expression of SKP2 and an up-regulation of β-TrCP1 expression. Up-regulation of β-TrCP1, thereby accelerating the ubiquitin-dependent degradation of CDK4 and ultimately inhibiting the malignant proliferation of the GB cells.

CONCLUSION

This study discovered a significant increase in SelK expression in GB patients with poor prognosis, revealing a negative correlation between SelK expression and patient outcomes. Further mechanistic investigations revealed that SelK enhances the proliferation of GB cells by targeting the endoplasmic reticulum stress/SKP2/β-TrCP1/CDK4 axis.

The crosstalk between non-coding RNAs and cell-cycle events: A new frontier in cancer therapy

The cell cycle comprises sequential events during which a cell duplicates its genome and divides it into two daughter cells. This process is tightly regulated to ensure that the daughter cell receives identical copied chromosomal DNA and that any errors in the DNA during replication are correctly repaired. Cyclins and their enzyme partners, cyclin-dependent kinases (CDKs), are critical regulators of G- to M-phase transitions during the cell cycle. Mitogenic signals induce the formation of the cyclin/CDK complexes, resulting in phosphorylation and activation of the CDKs. Once activated, cyclin/CDK complexes phosphorylate specific substrates that drive the cell cycle forward. The sequential activation and inactivation of cyclin-CDK complexes are tightly controlled by activating and inactivating phosphorylation events induced by cell-cycle proteins. The non-coding RNAs (ncRNAs), which do not code for proteins, regulate cell-cycle proteins at the transcriptional and translational levels, thereby controlling their expression at different cell-cycle phases. Deregulation of ncRNAs can cause abnormal expression patterns of cell-cycle-regulating proteins, resulting in abnormalities in cell-cycle regulation and cancer development. This review explores how ncRNA dysregulation can disrupt cell division balance and discusses potential therapeutic approaches targeting these ncRNAs to control cell-cycle events in cancer treatment.

CRTAC1 enhances the chemosensitivity of non-small cell lung cancer to cisplatin by eliciting RyR-mediated calcium release and inhibiting Akt1 expression

Sensitivity to platinum-based combination chemotherapy is associated with a favorable prognosis in patients with non-small cell lung cancer (NSCLC). Here, our results obtained from analyses of the Gene Expression Omnibus database of NSCLC patients showed that cartilage acidic protein 1 (CRTAC1) plays a role in the response to platinum-based chemotherapy. Overexpression of CRTAC1 increased sensitivity to cisplatin in vitro, whereas knockdown of CRTAC1 decreased chemosensitivity of NSCLC cells. In vivo mouse experiments showed that CRTAC1 overexpression increased the antitumor effects of cisplatin. CRTAC1 overexpression promoted NFAT transcriptional activation by increasing intracellular Ca2+ levels, thereby inducing its regulated STUB1 mRNA transcription and protein expression, accelerating Akt1 protein degradation and, in turn, enhancing cisplatin-induced apoptosis. Taken together, the present results indicate that CRTAC1 overexpression increases the chemosensitivity of NSCLC to cisplatin treatment by inducing Ca2+-dependent Akt1 degradation and apoptosis, suggesting the potential of CRTAC1 as a biomarker for predicting cisplatin chemosensitivity. Our results further reveal that modulating the expression of CRTAC1 could be a new strategy for increasing the efficacy of cisplatin in chemotherapy of NSCLC patients.

circRNF10 Regulates Tumorigenic Properties and Natural Killer Cell-Mediated Cytotoxicity against Breast Cancer through the miR-934/PTEN/PI3k-Akt Axis

Circular RNA (circRNA), a type of non-coding RNA, has received a great deal of attention with regard to the initiation and progression of tumors. However, the molecular mechanism and function of circRNAs in breast cancer (BC) remain unclear. In the current study, we discovered that hsa_circ_0028899 (also called circRNF10) was significantly reduced in BC tissues, and a higher level of circRNF10 was markedly related to a favorable prognosis. The results of CCK8, colony formation, Transwell, ELISA, and NK cell-mediated cytotoxicity assays indicated that increased circRNF10 expression could significantly repress the proliferation, invasion, and migration of BC cells and enhance the killing efficiency of NK cells against BC cells. According to these biological functions, the possible role and molecular mechanism of circRNF10 in BC cells were further investigated. We used bioinformatics prediction tools to predict circRNF10-bound miRNAs, which were verified by many experimental studies, including FISH, luciferase reporter assays, RIP, and Western blots. These data suggest that circRNF10 serves as a molecular sponge for miR-934 to further regulate PTEN expression and PI3k/Akt/MICA signaling in vitro and tumor growth in vivo. Altogether, these findings reveal that circRNF10 functions as a novel anti-oncogene in BC via sponging miR-934 and suppressing the PI3K/Akt/MICA pathway.

TRIM14 inhibits OPTN-mediated autophagic degradation of KDM4D to epigenetically regulate inflammation

Histone methylation regulates gene transcription through a variety of methylases and demethylases. The regulatory role of autophagy, an important process of protein degradation and recycling, in these histone modifiers is still unclear. We report that TRIM14 stabilized the histone demethylase KDM4D to facilitate the transcription of interleukin 12 (Il12) and Il23 by inhibiting histone H3K9 trimethylation in vitro and in vivo. Mechanistically, TRIM14 recruited the deubiquitinases USP14 and BRCC3 to remove the K63-linked ubiquitin chains of KDM4D and prevented it from undergoing optineurin-mediated autophagic degradation. This study is valuable not only for increasing our understanding of the cross-talk between autophagy and epigenetic regulation, but also for demonstrating the potential of TRIM14 as a target for therapeutic interventions for inflammation-related diseases.

Autophagy is a fundamental cellular process of protein degradation and recycling that regulates immune signaling pathways via multiple mechanisms. However, it remains unclear how autophagy epigenetically regulates the immune response. Here, we identified TRIM14 as an epigenetic regulator that reduces histone H3K9 trimethylation by inhibiting the autophagic degradation of the histone demethylase KDM4D. TRIM14 recruited the deubiquitinases USP14 and BRCC3 to cleave the K63-linked ubiquitin chains of KDM4D, which prevented KDM4D from undergoing optineurin (OPTN)-mediated selective autophagy. Tripartite motif-containing 14 (TRIM14) deficiency in dendritic cells significantly impaired the expression of the KDM4D-directed proinflammatory cytokines interleukin 12 (Il12) and Il23 and protected mice from autoimmune inflammation. Taken together, these findings highlight the cross-talk between epigenetic regulation and autophagy and suggest TRIM14 is a potential target of therapeutic intervention for inflammation-related diseases.

Ubiquitination-Related Molecular Subtypes and a Novel Prognostic Index for Bladder Cancer Patients

Objective: To develop and validate ubiquitination-related molecular subtypes and a novel prognostic index using ubiquitination-related genes (URGs) for patients with bladder cancer (BCa).

Materials and Methods: We downloaded the clinical data and transcriptome data of BCa from TCGA and GEO database. Consensus clustering analysis was conducted to identify ubiquitination-related molecular subtypes for BCa. Besides, we performed univariate and multivariate Cox regression analysis to develop a novel prognostic URGs-related index for BCa. We conducted internal and external verification in TCGA cohort and GEO cohort, respectively. Furthermore, the associations of ubiquitination-related molecular subtypes and prognostic index with tumor immune environment were also investigated.

Results: A total of four ubiquitination-related molecular subtypes of BCa were finally identified. These four molecular subtypes had significantly different clinical characteristics, prognosis, PD-L1 expression level and tumor microenvironment. Besides, we developed a novel prognostic index using six URGs (including HLA-A, TMEM129, UBE2D1, UBE2N, UBE2T and USP5). The difference in OS between high and low-risk group was statistically significant in training cohort, testing cohort, and validating cohort. The area under ROC curve (AUC) for OS prediction was 0.736, 0.723, and 0.683 in training cohort, testing cohort, and validating cohort, respectively. Multivariate survival analysis showed that this index was an independent predictor for OS. This prognostic index was especially suitable for subtype 1 and 3, older, male, high grade, AJCC stage III-IV, stage N0, stage T3-4 BCa patients.

Conclusions: This study identified a total of four ubiquitination-related molecular subtypes with significantly different tumor microenvironment, prognosis, clinical characteristics and PD-L1 expression level. Besides, a novel ubiquitination-related prognostic index for BCa patients was developed and successfully verified, which performed well in predicting prognosis of BCa.

MicroRNA-934 facilitates cell proliferation, migration, invasion and angiogenesis in colorectal cancer by targeting B-cell translocation gene 2

Colorectal cancer (CRC) is a global public health issue with increasing prevalence. MicroRNA-934 (miR-934) is a kind of non-coding RNA involved in the regulation of diverse cancers. Though previous researches have revealed part of association between miR-934 and CRC, the role of miR-934 in CRC pathogenesis has not been completely explored yet. In this study, we aim to investigate the effect of miR-934 on cell proliferation, migration, invasion and angiogenesis in CRC. Accordingly, miR-934 was found to be over-expressed in SW480 and HCT116 cells, two typical CRC cell lines. Meanwhile, miR-934 knockdown significantly inhibited cell proliferation and induced cell cycle arrest in SW480 and HCT116 cells. It was further validated that miR-934 knockdown displayed an inhibitory effect on cell migration and invasion in SW480 and HCT116 cells. Additionally, miR-934 deficiency markedly decreased VEGF expression in SW480 and HCT116 cells and suppressed capability of CRC cells to promote tube formation in vascular endothelial cells, which suggests the pro-angiogenesis role of miR-934 in vitro. Dual luciferase reporter assay further showed that miR-934 directly bound to B-cell translocation gene 2 (BTG2). BTG2 knockdown reversed the inhibitory effect of miR-934 silencing on cell proliferation, migration, invasion, and angiogenesis in SW480 and HCT116 cells. In summary, this study suggests that miR-934 facilitates CRC progression by targeting BTG2, and further highlights the role of miR-934 in pathogenesis of CRC.

Circular RNA CircPPP1CB Suppresses Tumorigenesis by Interacting With the MiR-1307-3p/SMG1 Axis in Human Bladder Cancer

Circular RNA (circRNA) is a newly discovered endogenous non-coding RNA (ncRNA), which is characterized with a closed circular structure. A growing body of evidence has verified the vital roles of circRNAs in human cancer. In this research, we selected circPPP1CB as a study object by circRNA sequencing and quantitative real-time PCR (qRT-PCR) validation in human bladder cancer (BC). CircPPP1CB is downregulated in BC and is negatively correlated with clinical stages and histological grades. Functionally, circPPP1CB modulated cell growth, metastasis, and epithelial-to-mesenchymal transition (EMT) process in vitro and in vivo. Mechanically, we performed various experiments to verify the circPPP1CB/miR-1307-3p/SMG1 regulatory axis. Taken together, our results demonstrated that circPPP1CB participates in tumor growth, metastasis, and EMT process by interacting with the miR-1307-3p/SMG1 axis, and that circPPP1CB might be a novel therapeutic target and diagnostic biomarker in human BC.

MicroRNA-934 promotes colorectal cancer cell proliferation by directly targeting Dickkopf-related protein 2

Increasing evidence demonstrates that dysregulation of microRNAs (miRNAs/miRs) is implicated in the development of colorectal cancer. However, the biological functions of several differentially expressed miRNAs remain unknown. In the present study, a bioinformatic analysis of a previously published microarray data and reverse transcription-quantitative PCR analysis demonstrated that miR-934 expression was upregulated in colorectal cancer samples collected from patients. Mechanistically, Dickkopf-related protein 2 (DDK2) was identified as a novel target gene of miR-934 in colorectal cancer cells. Knockdown of DDK2 reversed the inactivation of Wnt signaling pathway induced using miR-934 inhibitor in colorectal cancer cells. In addition, DDK2 silencing reversed miR-934 inhibitor-induced cell proliferation inhibition and elevation of cell apoptosis. The results demonstrated that DDK2 mRNA expression was negatively associated with miR-934 expression in colorectal tumors. Collectively, the results of the present study demonstrated that the miR-934/DDK2 axis regulated colorectal cancer cell proliferation, suggesting that miR-934 may be a biomarker for patients with colorectal cancer.

miR-934 promotes breast cancer metastasis by regulation of PTEN and epithelial-mesenchymal transition

Breast cancer (BC) is the most commonly diagnosed malignancy and the leading cause of cancer-related mortality among females. Over 90 % of the cases of death in BC patients are attributed to tumor cell metastasis. Therefore, it is urgently needed to investigate the molecular mechanisms of BC metastasis. The expression of miRNA in BC was evaluated by qRT-PCR and bioinformatics analysis. Clone formation, EdU assays, and subcutaneous xenograft model were used to test the growth of BC cells. Wound healing, transwell assays, and lung-metastasis model were used to explore the effect of miR-934 knockdown on cell metastasis. The miR-934 targets in BC were identified through bioinformatics analysis and luciferase reporter assays. The expression of protein was tested by western blot. The binding of mRNA and RNA-binding-protein was verified using RIP assays. miR-934 expression was significantly elevated in BC tissues, especially in those with lymph node metastasis and associated with poor patient prognosis. Experiments in vitro and in vivo showed that that upregulated miR-934 was not necessarily required for the growth of BC cells. However, miR-934 knockdown significantly inhibited the migration and invasion abilities of BC cells. Moreover, PTEN as identified as the direct target of miR-934 in BC, and miR-934 could promote BC cell metastasis by regulation of PTEN and epithelial-mesenchymal transition (EMT). Our results suggested that targeting miR-934 may be a practical treatment for BC cell metastasis.

uc.77- Downregulation Promotes Colorectal Cancer Cell Proliferation by Inhibiting FBXW8-Mediated CDK4 Protein Degradation

Transcribed ultraconserved regions (T-UCRs) are a new type of long non-coding RNA, and the UCR has 481 segments longer than 200 base pairs that are 100% conserved between humans, rats, and mice. T-UCRs involved in colorectal cancer (CRC) have not been studied in detail. We performed T-UCR microarray analysis and found that uc.77- was significantly downregulated in CRC tissues and cell lines. Ectopic expression of uc.77- significantly inhibited the proliferation of CRC cells in vitro and the growth of xenograft tumors in nude mice in vivo. Mechanistic studies showed that uc.77- competed with FBXW8 mRNA for binding to microRNA (miR)-4676-5p through a competing endogenous RNA mechanism and inhibited the proliferation of CRC cells by negatively regulating CDK4. The present findings highlight the role of the uc.77-/miR-4676-5p/FBXW8 axis in CRC and identify uc.77- as a potential novel target for the treatment of CRC.

miR-190 promotes malignant transformation and progression of human urothelial cells through CDKN1B/p27 inhibition

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.

Coiled-Coil Domain-Containing 68 Downregulation Promotes Colorectal Cancer Cell Growth by Inhibiting ITCH-Mediated CDK4 Degradation

Coiled-coil domain-containing 68 (CCDC68) plays different roles in cancer and is predicted as a tumor suppressor in human colorectal cancer (CRC). However, the specific role of CCDC68 in CRC and the underlying mechanisms remain unknown. Here, we showed that CCDC68 expression was lower in CRC than that in corresponding normal tissues, and CCDC68 level was positively correlated with disease-free survival. Ectopic expression of CCDC68 decreased CRC cell proliferation in vitro and suppressed the growth of CRC xenograft tumors in vivo. CCDC68 caused G0/G1 cell cycle arrest, downregulated CDK4, and upregulated ITCH, the E3 ubiquitin ligase responsible for CDK4 protein degradation. This increased CDK4 degradation, which decreased CDK4 protein levels and inhibited CRC tumor growth. Collectively, the present results identify a novel CDK4 regulatory axis consisting of CCDC68 and ITCH, which suggest that CCDC68 is a promising target for the treatment of CRC.

Oncogenic role of MIR516A in human bladder cancer was mediated by its attenuating PHLPP2 expression and BECN1-dependent autophagy

Although MIR516A has been reported to be downregulated and act as a tumor suppressor in multiple cancers, its expression and potential contribution to human bladder cancer (BC) remain unexplored. Unexpectedly, we showed here that MIR516A was markedly upregulated in human BC tissues and cell lines, while inhibition of MIR516A expression attenuated BC cell monolayer growth in vitro and xenograft tumor growth in vivo, accompanied with increased expression of PHLPP2. Further studies showed that MIR516A was able to directly bind to the 3'-untranslated region of PHLPP2 mRNA, which was essential for its attenuating PHLPP2 expression. The knockdown of PHLPP2 expression in MIR516A-inhibited cells could reverse BC cell growth, suggesting that PHLPP2 is a MIR516A downstream mediator responsible for MIR516A oncogenic effect. PHLPP2 was able to mediate BECN1/Beclin1 stabilization indirectly, therefore promoting BECN1-dependent macroautophagy/autophagy, and inhibiting BC tumor cell growth. In addition, our results indicated that the increased autophagy by attenuating MIR516A resulted in a dramatic inhibition of xenograft tumor formation in vivo. Collectively, our results reveal that MIR516A has a novel oncogenic function in BC growth by directing binding to PHLPP2 3'-UTR and inhibiting PHLPP2 expression, in turn at least partly promoting CUL4A-mediated BECN1 protein degradation, thereby attenuating autophagy and promoting BC growth, which is a distinct function of MIR516A identified in other cancers.Abbreviation: ATG3: autophagy related 3; ATG5: autophagy related 5; ATG7: autophagy related 7; ATG12: autophagy related 12; BAF: bafilomycin A1; BC: bladder cancer; CHX: cycloheximide; Co-IP: co-immunoprecipitation; CUL3: cullin 3; CUL4A: cullin 4A; CUL4B: cullin 4B; IF: immunofluorescence: IHC-p: immunohistochemistry-paraffin; MIR516A: microRNA 516a (microRNA 516a1 and microRNA 516a2); MS: mass spectrometry; PHLPP2: PH domain and leucine rich repeat protein phosphatase.

MicroRNA-32-5p inhibits epithelial-mesenchymal transition and metastasis in lung adenocarcinoma by targeting SMAD family 3

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-associated death worldwide. MicroRNA (miRNA)-32-5p is as an important cancer-associated miRNA in different types cancer. To date, the role of miR-32-5p in the migration and invasion of NSCLC remains unknown. In the present study, a Transwell assay was performed to investigate the role of miR-32-5p in lung adenocarcinoma. miR-32-5p expression level was determined via reverse transcription-quantitative PCR in 24 pairs of NSCLC and adjacent normal tissues. SMAD family member 3 (SMAD3) was considered as a novel target gene by luciferase reporter assay and western blot in NSCLC. The present study demonstrated that miR-32-5p is frequently downregulated in NSCLC tissues. The overexpression of miR-32-5p resulted in the inhibition of migratory and invasive abilities in NSCLC cells. Thus, SMAD3 was identified as a target of miR-32-5p, and its expression was negatively correlated with miR-32-5p expression in clinical NSCLC tissues. Overall, these findings indicate that miR-32-5p serves as a tumor suppressor by targeting SMAD3. Thus, miR-32-5p may be a potential therapeutic target for the treatment of lung adenocarcinoma.

Tumor-derived exosomal miR-934 induces macrophage M2 polarization to promote liver metastasis of colorectal cancer

Background

Mounting evidence has demonstrated the vital importance of tumor-associated macrophages (TAMs) and exosomes in the formation of the premetastatic niche. However, the molecular mechanisms by which tumor-derived exosomal miRNAs interact with TAMs underlying premetastatic niche formation and colorectal cancer liver metastasis (CRLM) remain largely unknown.

Methods

Transmission electron microscopy and differential ultracentrifugation were used to verify the existence of exosomes. In vivo and in vitro assays were used to identify roles of exosomal miR-934. RNA pull-down assay, dual-luciferase reporter assay, etc. were applied to clarify the mechanism of exosomal miR-934 regulated the crosstalk between CRC cells and M2 macrophages.

Results

In the present study, we first demonstrated the aberrant overexpression of miR-934 in colorectal cancer (CRC), especially in CRLM, and its correlation with the poor prognosis of CRC patients. Then, we verified that CRC cell-derived exosomal miR-934 induced M2 macrophage polarization by downregulating PTEN expression and activating the PI3K/AKT signaling pathway. Moreover, we revealed that hnRNPA2B1 mediated miR-934 packaging into exosomes of CRC cells and then transferred exosomal miR-934 into macrophages. Interestingly, polarized M2 macrophages could induce premetastatic niche formation and promote CRLM by secreting CXCL13, which activated a CXCL13/CXCR5/NFκB/p65/miR-934 positive feedback loop in CRC cells.

Conclusions

These findings indicate that tumor-derived exosomal miR-934 can promote CRLM by regulating the crosstalk between CRC cells and TAMs. These findings reveal a tumor and TAM interaction in the metastatic microenvironment mediated by tumor-derived exosomes that affects CRLM. The present study also provides a theoretical basis for secondary liver cancer.

miR-934 as a Prognostic Marker Facilitates Cell Proliferation and Migration of Pancreatic Tumor by Targeting PROX1

Background

Pancreatic cancer is an extremely lethal digestive cancer with late diagnosis and poor prognosis. miR-934 has been reported to serve as an oncogene in multiple cancers, such as ovarian cancer and bladder cancer. However, its role in pancreatic cancer remains undiscovered.

Materials and Methods

The expression data of miR-934 were obtained from the Gene Expression Omnibus database and from our own patient samples. The clinicopathological data and corresponding follow-up data were retrieved from The Cancer Genome Atlas database. CCK8 and colony formation assays were conducted to measure cell proliferation capacity in vitro. Wound healing and transwell assays were performed to detect the migration ability of pancreatic cancer cell.

Results

We found that miR-934 was significantly upregulated in pancreatic tumor samples and cell lines. The expression of miR-934 was related to pathological stages. Upregulated miR-934 was associated with poor prognosis in patients with pancreatic cancer. Mir-934 inhibition reduced, while overexpression promoted, cell proliferation and migration. Mechanically, we found  miR-934 could directly bind to 3'-UTR of PROX1 leading to mRNA derogation. Furthermore, increased cell proliferation and migration caused by miR-934 overexpression could be reversed by forced PROX1 expression.

Conclusion

miR-934 is an oncogene in pancreatic cancer and could serve as a prognosis indicator for patients with pancreatic cancer, suggesting that miR-934 is a promising therapeutic target for pancreatic cancer.

An ATF24 peptide-functionalized β-elemene-nanostructured lipid carrier combined with cisplatin for bladder cancer treatment

Objective: In this study, we aimed to develop an amino-terminal fragment (ATF) peptide-targeted liposome carrying β-elemene (ATF₂₄-PEG-Lipo-β-E) for targeted delivery into urokinase plasminogen activator receptor-overexpressing bladder cancer cells combined with cisplatin (DDP) for bladder cancer treatment.

Methods: The liposomes were prepared by ethanol injection and high-pressure microjet homogenization. The liposomes were characterized, and the drug content, entrapment efficiency, and in vitro release were studied. The targeting efficiency was investigated using confocal microscopy, ultra-fast liquid chromatography, and an orthotopic bladder cancer model. The effects of ATF₂₄-PEG-Lipo-β-E combined with DDP on cell viability and proliferation were evaluated by a Cell Counting Kit-8 (CCK-8) assay, a colony formation assay, and cell apoptosis and cell cycle analyses. The anticancer effects were evaluated in a KU-19-19 bladder cancer xenograft model.

Results: ATF₂₄-PEG-Lipo-β-E had small and uniform sizes (˜79 nm), high drug loading capacity (˜5.24 mg/mL), high entrapment efficiency (98.37 ± 0.95%), and exhibited sustained drug release behavior. ATF₂₄-PEG-Lipo-β-E had better targeting efficiency and higher cytotoxicity than polyethylene glycol (PEG)ylated β-elemene liposomes (PEG-Lipo-β-E). DDP, combined with ATF₂₄-PEG-Lipo-β-E, exerted a synergistic effect on cellular apoptosis and cell arrest at the G2/M phase, and these effects were dependent on the caspase-dependent pathway and Cdc25C/Cdc2/cyclin B1 pathways. Furthermore, the in vivo antitumor activity showed that the targeted liposomes effectively inhibited the growth of tumors, using the combined strategy.

Conclusions: The present study provided an effective strategy for the targeted delivery of β-elemene (β-E) to bladder cancer, and a combined strategy for bladder cancer treatment.