ABSTRACT
Myelodysplastic syndromes (MDS) are clonal hematopoietic malignancies and seriously threaten people's health. Current therapies include bone marrow transplantation and several hypomethylating agents. However, many elderly patients cannot benefit from bone marrow transplantation and many patients develop drug resistance to hypomethylating agents, making it urgent to explore novel therapy. RSL3 can effectively induce ferroptosis in various tumors and combination of RSL3 and hypomethylating agents is promising to treat many tumors. However, its effect in MDS was unknown. In this study, we found that RSL3 inhibited MDS cell proliferation through inducing ROS-dependent apoptosis. RSL3 inhibited Bcl-2 expression and increased caspase 3 and PARP cleavage. RNA-seq analysis revealed that MYB may be a potential target of RSL3. Rescue experiments showed that overexpression of MYB can rescue MDS cell proliferation inhibition caused by RSL3. Cellular thermal shift assay showed that RSL3 binds to MYB to exert its function. Furthermore, RSL3 inhibited tumor growth and decreased MYB and Bcl-2 expression in vivo. More importantly, RSL3 decreased the viability of bone marrow mononuclear cells (BMMCs) isolated from MDS patients, and RSL3 had a synergistic effect with DAC in MDS cells. Our studies have uncovered RSL3 as a promising compound and MYB/Bcl-2 signaling pathway as a potential target for MDS treatment.
Subject(s)
Apoptosis , Myelodysplastic Syndromes , Proto-Oncogene Proteins c-bcl-2 , Proto-Oncogene Proteins c-myb , Reactive Oxygen Species , Signal Transduction , Myelodysplastic Syndromes/pathology , Myelodysplastic Syndromes/metabolism , Myelodysplastic Syndromes/genetics , Humans , Apoptosis/drug effects , Proto-Oncogene Proteins c-bcl-2/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-myb/metabolism , Proto-Oncogene Proteins c-myb/genetics , Reactive Oxygen Species/metabolism , Animals , Mice , Cell Proliferation , Mice, Nude , Male , FemaleABSTRACT
Circadian clock perturbation frequently occurs in cancer and facilitates tumor progression by regulating malignant growth and shaping the immune microenvironment. Emerging evidence has indicated that clock genes are disrupted in melanoma and linked to immune escape. Herein, we found that the expression of retinoic acid receptor-related orphan receptor-α (RORA) is downregulated in melanoma patients and that patients with higher RORA expression have a better prognosis after immunotherapy. Additionally, RORA was significantly positively correlated with T-cell infiltration and recruitment. Overexpression or activation of RORA stimulated cytotoxic T-cell-mediated antitumor responses. RORA bound to the CD274 promoter and formed an inhibitory complex with HDAC3 to suppress PD-L1 expression. In contrast, the DEAD-box helicase family member DDX3X competed with HDAC3 for binding to RORA, and DDX3X overexpression promoted RORA release from the suppressive complex and thereby increased PD-L1 expression to generate an inhibitory immune environment. The combination of a RORA agonist with an anti-CTLA4 antibody synergistically increased T-cell antitumor immunity in vivo. A score based on the combined expression of HDAC3, DDX3X, and RORA correlated with immunotherapy response in melanoma patients. Together, this study elucidates a mechanism of clock component-regulated antitumor immunity, which will help inform the use of immunotherapy and lead to improved outcomes for melanoma patients receiving combined therapeutic treatments. Significance: RORA forms a corepressor complex to inhibit PD-L1 expression and activate antitumor T-cell responses, indicating that RORA is a potential target and predictive biomarker to improve immunotherapy response in melanoma patients.
Subject(s)
B7-H1 Antigen , Circadian Clocks , Melanoma , Humans , Melanoma/immunology , Melanoma/pathology , Melanoma/genetics , Melanoma/metabolism , B7-H1 Antigen/metabolism , B7-H1 Antigen/genetics , B7-H1 Antigen/immunology , Animals , Mice , Circadian Clocks/genetics , Circadian Clocks/immunology , Nuclear Receptor Subfamily 1, Group F, Member 1/metabolism , Nuclear Receptor Subfamily 1, Group F, Member 1/genetics , Tumor Microenvironment/immunology , Histone Deacetylases/metabolism , Histone Deacetylases/genetics , Monitoring, Immunologic , Gene Expression Regulation, Neoplastic , Cell Line, Tumor , Mice, Inbred C57BL , Male , Female , DEAD-box RNA Helicases/genetics , DEAD-box RNA Helicases/metabolism , Immunotherapy/methods , PrognosisABSTRACT
BACKGROUND: Women with obesity and polycystic ovary syndrome (OPOS) are at high risk for infertility. However, the reproductive effects of metabolic surgery on women with infertility and OPOS have not been fully elucidated. OBJECTIVES: We investigated the natural conception rates after metabolic surgery, and the variables associated with infertility in women with OPOS. SETTING: Shanghai Sixth People's Hospital, Shanghai, China. METHODS: This study included 72 women with infertility and OPOS who underwent metabolic surgery and were followed up for 4 years after surgery. Finally, 54 patients completed the study. Reproductive outcomes were assessed, along with changes in anthropometric parameters and metabolic indices before and 1 year after surgery (prepregnancy). Logistic regression analysis was used to identify variables influencing natural conception and delivery outcomes. RESULTS: After metabolic surgery, 35 patients (64.8%) became pregnant naturally, while 16 were still unable to conceive naturally. Preoperative body mass index (BMI) tended to be lower in the natural conception group than in the no natural conception group (38.9 ± 6.9 versus 43.6 ± 11.0 kg/m2, P = .070) and there were no significant differences in weight loss between the 2 groups after surgery. Logistic regression analysis showed that the BMI 1 year after surgery (prepregnancy) was an independent predictor of natural conception, and receiver operating characteristic analysis showed that a BMI of 27.0 kg/m2 was the optimal cutoff for predicting successful natural conception after surgery. CONCLUSIONS: Metabolic surgery can improve fertility in women with OPOS. Patients with a BMI < 27.0 kg/m2 1 year after surgery (prepregnancy) are more likely to become pregnant naturally and give birth.
Subject(s)
Bariatric Surgery , Infertility, Female , Polycystic Ovary Syndrome , Pregnancy , Humans , Female , Polycystic Ovary Syndrome/complications , Polycystic Ovary Syndrome/surgery , Retrospective Studies , Infertility, Female/complications , Infertility, Female/surgery , China , Obesity/complications , Obesity/surgeryABSTRACT
Multiple myeloma (MM) is an incurable hematological malignant disorder of bone marrow. Patients with MM receive multiple lines of chemotherapeutic treatments which often develop bortezomib (BTZ) resistance and relapse. Therefore, it is crucial to identify an anti-MM agent to overcome the BTZ resistance of MM. In this study, we screened a library of 2370 compounds against MM wild-type (ARP1) and BTZ-resistant type (ARP1-BR) cell lines and found that periplocin (PP) was the most significant anti-MM natural compound. We further investigated the anti-MM effect of PP by using annexin V assay, clonogenic assays, aldefluor assay, and transwell assay. Furthermore, RNA sequencing (RNA-seq) was performed to predict the molecular effects of PP in MM followed by verification through qRT-PCR and Western blot analysis. Moreover, ARP1 and ARP1-BR xenograft mice models of MM were established to confirm the anti-MM effects of PP invivo. The results showed that PP significantly induced apoptosis, inhibited proliferation, suppressed stemness, and reduced the cell migration of MM. The expression of cell adhesion molecules (CAMs) was suppressed upon PP treatment in vitro and in vivo. Overall, our data recommend PP as an anti-MM natural compound with the potential to overcome BTZ resistance and downregulate CAMs in MM.
ABSTRACT
N6-methyladenosine (m6A) is the most prevalent, abundant and conserved type of internal posttranscriptional RNA modification in eukaryotic cells. Emerging evidence suggests that m6A modifications perform important functions that affect antitumor immunity. Programmed death 1 (PD-1) and programmed cell death-ligand 1 (PD-L1) are the two most well-studied immune checkpoint pathways. The interaction of PD-L1 with its receptor PD-1 inhibits cytotoxic T-cell-mediated tumor responses, and blockade of this interaction has proven to be an effective immunotherapy strategy in various cancers. Unfortunately, few cancer patients benefit from the two tools due to uncertain resistance. m6A plays an important role in affecting RNA biogenesis and process in various cancers. Understanding the molecular mechanism of drug resistance will promote the development of personalized clinical management. In this review, we systematically discussed the mechanisms by which m6A regulates PD-1 and PD-L1 expression and further their functions in the process of tumor immunotherapy and the potential application prospects of m6A-associated molecules. Moreover, mounting m6Ascore is established to evaluate the prognosis of cancer.
Subject(s)
B7-H1 Antigen , Programmed Cell Death 1 Receptor , Humans , Adenosine , Immunotherapy , RNAABSTRACT
Multiple myeloma (MM) is an incurable condition and the second most common hematological malignancy. Over the past few years, there has been progress in the treatment of MM, but most patients still relapse. Multiple myeloma stem-like cells (MMSCs) are believed to be the main reason for drug resistance and eventual relapse. Currently, there are not enough therapeutic agents that have been identified for eradication of MMSCs, and thus, identification of the same may alleviate the issue of relapse in patients. In the present study, we showed that luteolin (LUT), a natural compound obtained from different plants, such as vegetables, medicinal herbs, and fruits, effectively inhibits the proliferation of MM cells and overcomes bortezomib (BTZ) resistance in them in vitro and in vivo, mainly by decreasing the proportion of ALDH1+ cells. Furthermore, RNA sequencing after LUT treatment of MM cell lines and an MM xenograft mouse model revealed that the effects of the compound are mediated through inhibition of transforming growth factor-ß signaling. Similarly, we found that LUT also significantly reduced the proportion of ALDH1+ cells in primary CD138+ plasma cells. In addition, LUT could overcome the BTZ treatment-induced increase in the proportion of ALDH1+ cells, and the combination of LUT and BTZ had a synergistic effect against myeloma cells. Collectively, our findings suggested that LUT is a promising agent that manifests MMSCs to overcome BTZ resistance, alone or in combination with BTZ, and thus, is a potential therapeutic drug for the treatment of MM.
Subject(s)
Antineoplastic Agents , Multiple Myeloma , Humans , Animals , Mice , Bortezomib/pharmacology , Multiple Myeloma/pathology , Luteolin/pharmacology , Drug Resistance, Neoplasm , Apoptosis , Cell Line, Tumor , Neoplasm Recurrence, Local/drug therapy , Signal Transduction , Transforming Growth Factor beta/pharmacology , Antineoplastic Agents/pharmacologyABSTRACT
BACKGROUND: Influenza A (H3N2) virus (A/H3N2) has complex antigenic evolution, resulting in frequent vaccine strain updates. We aimed to evaluate the protective effect of the vaccine strains on the circulating strains from past ten years and provide a basis for finding a broader and more efficient A/H3N2 vaccine strain. METHODS: Eighty-four representative circulating A/H3N2 strains were selected from 65,791 deposited sequences in 2011-2020 and pseudotyped viruses were constructed with the VSV vector. We immunized guinea pigs with DNA vaccine containing the A/H3N2 components of the vaccine strains from 2011 to 2021 and tested neutralizing antibody against the pseudotyped viruses. We used a hierarchical clustering method to classify the eighty-four representative strains into different antigenic clusters. We also immunized animals with monovalent vaccine stock of the vaccine strains for the 2020-2021 and 2021-2022 seasons and tested neutralizing antibody against the pseudotyped viruses. FINDINGS: The vaccine strains PE/09, VI/11 and TE/12 induced higher levels of neutralizing antibody against representative strains circulating in recommended year and the year immediately prior whereas vaccine strains HK/14, HK/19 and CA/20 induced poor neutralization against all representative strains. The representative strains were divided into five antigenic clusters (AgV), which were not identical to gene clades. The AgV5 strains were most difficult to be protected among the five clusters. Compared with single-dose immunization, three doses of monovalent vaccine stock (HK/19 or CA/20) could induce stronger and broader neutralizing antibodies against strains in each of the antigenic clusters. INTERPRETATION: The protective effect of vaccine strains indicated that the accurate selection of A/H3N2 vaccine strains must remain a top priority. By increasing the frequency of immunization, stronger and broader neutralizing antibodies against strains in all antigenic clusters were induced, which provides direction for a new immunization strategy. FUNDING: This work was supported by a grant from National Key R&D Program of China (No. 2021YFC2301700).
Subject(s)
Influenza Vaccines , Influenza, Human , Guinea Pigs , Animals , Humans , Influenza A Virus, H3N2 Subtype/genetics , Seasons , Hemagglutination Inhibition Tests , Retrospective Studies , Antibodies, Neutralizing , Antibodies, ViralABSTRACT
AIM: This study aimed to investigate the role of lncRNA MCM3AP-AS1 in diabetic retinopathy (DR). METHODS: Plasma MCM3AP-AS1 levels in DR patients (n = 80), T2DM patients (n = 80), and Controls (n = 80) were measured by qPCR and compared using ANOVA (one-way) and Tukey test. The expressions of lncRNA MCM3AP-AS1 and miR-211 in Human retinal pigment epithelial cells (hRPE) line ARPE-19 were detected by RT-qPCR. Western blot and annexin V-FITC staining were performed to investigate the role of MCM3AP-AS1/SIRT1 in ARPE-19 cell proliferation and apoptosis in vitro. RESULTS: We observed that MCM3AP-AS1 was downregulated in DR patients 25 comparing to T2D patients without significantly complications. Bioinformatics analysis showed that MCM3AP-AS1 might bind miR-211. However, no significant correlation between these two factors was observed in DR patients. Consistently, overexpression of MCM3AP-AS1 and miR-211 failed to affect the expression of each other in hRPE. Interestingly, MCM3AP-AS1 overexpression upregulated SIRT1, a target of miR-211. Moreover, MCM3AP-AS1 was downregulated in DR patients compared to type 2 diabetic mellitus patients without significant complications. In RPEs, high glucose treatment downregulated MCM3AP-AS1. Cell apoptosis analysis showed that MCM3AP-AS1 and SIRT1 overexpression decreased the apoptotic rate of RPEs, and miR-211 overexpression reduced the effect of MCM3AP-AS1 and SIRT1 overexpression. CONCLUSION: MCM3AP-AS1 is downregulated in DR and promotes cell apoptosis by regulating miR-211/SIRT1.
ABSTRACT
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, particularly those with multiple mutations in receptor-binding domain (RBD), pose a critical challenge to the efficacy of coronavirus disease 2019 (COVID-19) vaccines and therapeutic neutralizing monoclonal antibodies (mAbs). Omicron sublineages BA.1, BA.2, BA.3, as well as the recent emergence of C.1.2, B.1.630, B.1.640.1, and B.1.640.2, have multiple mutations in RBD and may lead to severe neutralizing antibody evasion. It is urgent to evaluate the antigenic change of the above seven variants against mAbs and sera from guinea pigs immunized with variants of concern (VOCs) (Alpha, Beta, Gamma, Delta, Omicron) and variants of interest (VOIs) (Lambda, Mu) immunogens. Only seven out of the 24 mAbs showed no reduction in neutralizing activity against BA.1, BA.2, and BA.3. However, among these seven mAbs, the neutralization activity of XGv337 and XGv338 against C.1.2, B.1.630, B.1.640.1, and B.1.640.2 were decreased. Therefore, only five neutralizing mAbs showed no significant change against these seven variants. Using VOCs and VOIs as immunogens, we found that the antigenicity of variants could be divided into three clusters, and each cluster showed similar antigenicity to different immunogens. Among them, D614G, B.1.640.1, and B.1.630 formed a cluster, C.1.2 and B.1.640.2 formed a cluster, and BA.1, BA.2, and BA.3 formed a cluster.
ABSTRACT
Alpine treeline is highly sensitive to climate change, but there remains a lack of research on the spatiotemporal heterogeneity of treeline and their relationships with climate change at the landscape scale. We extracted positions of alpine treeline from high-resolution Google Earth images from three periods (2000, 2010, and 2020) and analyzed the elevation patterns and dynamics of treeline positions in the Hengduan Mountains. Based on the treeline positions in 2020, a buffer zone of 300 m is established as the treeline transition zone, and the changing trend of the fraction vegetation cover (FVC) from 2000 to 2020 and its relationship with climate are also analyzed. Due to the special geographical and climatic environment, the treeline in the Hengduan Mountains area is high in the middle but lower in the surrounding areas. We found that over the past 20 years, the treeline position did not change significantly but that the FVC increased in 80.3% of the treeline areas. The increase in FVC was related to the decrease in precipitation in the growing season. The results also revealed a special exposure effect on the alpine treeline in the Hengduan Mountains. Because of the lower treeline, isotherm position caused by the monsoon climate, the treeline position on south-facing slopes is lower than that on slopes with other exposures. Our results confirmed that the pattern and dynamics of the alpine treeline are driven by the regional monsoon climate regime.
ABSTRACT
Chronic myelomonocytic leukemia (CML) is a myeloid tumor characterized by MDS (myelodysplastic syndrome) and MPN (myeloproliferative neoplasms). Allogeneic hematopoietic stem cell transplantation, chemotherapy, interferon, and targeted therapy are the main treatment methods for CML. Tyrosine kinase inhibitors (TKIs) are also a treatment option, and patients are currently recommended to take these drugs throughout their lives to prevent CML recurrence. Therefore, there is a need to investigate and identify other potential chemotherapy drugs. Currently, research on CML treatment with a single drug has shown little progress. Fingolimod (FTY720), an FDA-approved drug used to treat relapsing multiple sclerosis, has also shown great potential in the treatment of lymphocytic leukemia. In our study, we find that FTY720 and curcumol have a significant inhibitory effect on K562 cells, K562/ADR cells, and CD34+ cells from CML patients. RNAseq data analysis shows that regulation of apoptosis and differentiation pathways are key pathways in this process. Besides, BCR/ABL-Jak2/STAT3 signaling, PI3K/Akt-Jnk signaling, and activation of BH3-only genes are involved in CML inhibition. In a K562 xenograft mouse model, therapy with curcumol and FTY720 led to significant inhibition of tumor growth and induction of apoptosis. To summarize, curcumol and FTY720 synergistically inhibit proliferation involved in differentiation and induce apoptosis in CML cells. Therefore, synergistic treatment with two drugs could be the next choice of treatment for CML.
Subject(s)
Fingolimod Hydrochloride/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Sesquiterpenes/therapeutic use , Animals , Apoptosis , Cell Differentiation , Cell Proliferation , Disease Models, Animal , Fingolimod Hydrochloride/pharmacology , Humans , Mice , Sesquiterpenes/pharmacology , Signal TransductionABSTRACT
[This corrects the article DOI: 10.1186/s12935-019-1087-4.].
ABSTRACT
Melanoma is a common skin cancer and it can lead to high mortality probably by early invasion and metastasis. LncRNA MIAT is involved in tumor proliferation, invasion and epithelial-to-mesenchymal transition (EMT). However, the roles of MIAT in melanoma still require further investigation. Thus, the aim of the study is to investigate the roles of MIAT in melanoma, especially the effects of MIAT on EMT of melanoma cancer cells. The results showed that the expression of MIAT was significantly upregulated in melanoma tissue and cells compared with the normal skin and normal melanocytes; moreover, miR-150 was confirmed as a target of MIAT. Furthermore, knockdown of MIAT inhibited cell proliferation and invasion in melanoma cancer cells and transfection of miR-150 inhibitors partial abrogated the anti-tumor effects of MIAT siRNA. In addition, MIAT siRNA also inhibited the EMT of melanoma cells, while miR-150 inhibitors can reverse the effects of MIAT siRNA. Finally, knockdown of MIAT also inhibited the carcinogenic effects of melanoma in vivo by targeting miR-150. In conclusion, we reported that MIAT promotes the proliferation, invasion and EMT of melanoma cells via targeting miR-150, which suggested that MIAT might be a therapeutic target for the treatment of melanoma.
Subject(s)
Melanoma/genetics , Melanoma/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/physiology , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Epithelial-Mesenchymal Transition/genetics , Humans , Melanoma/therapy , Molecular Targeted Therapy , Neoplasm Invasiveness/genetics , Skin Neoplasms/therapyABSTRACT
Multiple myeloma stem-like cells (MMSCs) are responsible for initiation and relapse, though novel treatment paradigms that effectively eradicate MMSCs are yet to be developed. Selective inhibition of the cell cycle regulatory kinase Wee1 by MK1775 is being explored as a potential anti-cancer therapeutic. We report that higher expression of Wee1 is correlated with poor survival in multiple myeloma (MM). The MM models and patient-derived CD138+ plasma cells are particularly sensitive to the growth-inhibitory effects of the Wee1 inhibitor MK1775. MK1775 induces Mus81-Eme1 endonuclease-mediated DNA damage in S-phase cell cycle that results in a blockade of replication and then apoptosis. Furthermore, MK1775 strongly suppresses the features of stemness in vitro, in vivo and in primary CD138+ cells by decreasing ALDH1+ cell fraction and the expression of ALDH1. In addition, co-treatment of MK1775 with bortezomib is synergistic in vitro and in vivo. Bortezomib, although it enhances ALDH1+ cells, when combined with MK1775 abrogates this stimulatory effect on stemness. Considering MM as an invariably incurable malignancy due to the presence of heterogenic myeloma stem-like cells, our study presents inhibition of Wee1 as a promising targeted therapy for MM and provides a compelling rationale to further investigate the activity of MK1775 against myeloma in clinical settings.
Subject(s)
Bortezomib/pharmacology , Cell Cycle Proteins/antagonists & inhibitors , Multiple Myeloma , Neoplasm Proteins/antagonists & inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Pyrazoles/pharmacology , Pyrimidinones/pharmacology , Animals , Bortezomib/agonists , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Drug Synergism , Humans , Mice , Multiple Myeloma/drug therapy , Multiple Myeloma/enzymology , Neoplasm Proteins/metabolism , Protein-Tyrosine Kinases/metabolism , Pyrazoles/agonists , Pyrimidinones/agonists , Xenograft Model Antitumor AssaysABSTRACT
Multiple myeloma (MM) is characterised by the proliferation and accumulation of malignant plasma cells in the bone marrow. Despite the progress in treatment over the last few years, MM remains incurable and the majority of patients relapse. MM stem-like cells (MMSCs) have been considered as the main reason for drug resistance and eventual relapse. Currently, therapeutic agents are not enough to eradicate MMSCs, and finding effective strategies to eradicate MMSCs may improve the outcome of patients. Here we showed that lycorine, a natural compound from the Amaryllidaceae species, effectively inhibits the proliferation of myeloma cells from cell lines or patients, mainly through decreasing ALDH1+ cells. Mechanistically, lycorine decreases the MMSC population through inhibition of the Wnt/ß-catenin pathway by reducing the ß-catenin protein level. Moreover, lycorine could overcome the increasing proportion of ALDH1+ cells caused by bortezomib (BTZ) treatment, and a combination BTZ and lycorine have a synergistic effect on anti-myeloma cells. Furthermore, we found a similar reduction of MMSC characteristics by lycorine in BTZ-resistant MM cells and primary CD138+ plasma cells. Collectively, our findings indicate lycorine as a promising agent to target MMSCs to overcome the drug resistance of BTZ, and that, alone or in combination with BTZ, lycorine is a potential therapeutic strategy for MM treatments.
Subject(s)
Amaryllidaceae Alkaloids/pharmacology , Multiple Myeloma , Neoplasm Proteins/metabolism , Neoplastic Stem Cells , Phenanthridines/pharmacology , Wnt Signaling Pathway/drug effects , beta Catenin/metabolism , Cell Line, Tumor , Humans , Multiple Myeloma/drug therapy , Multiple Myeloma/metabolism , Multiple Myeloma/pathology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathologyABSTRACT
BACKGROUND: Melanoma is the most aggressive type of skin cancer with high mortality rate and poor prognosis. lncRNA MEG3, a tumor suppressor, is closely related to the development of various cancers. However, the role of lncRNA MEG3 in melanoma has seldom been studied. METHODS: RT-PCR was used to examine the expressions of lncRNA MEG3 and E-cadherin in melanoma patients and cell lines. Then, the biological functions of lncRNA MEG3 and E-cadherin were demonstrated by transfecting lncRNA MEG3-siRNA, lncRNA MEG3-overexpression, E-cadherin-siRNA and E-cadherin-overexpression plasmids in melanoma cell lines. Moreover, CCK8 assay and colony formation assay were utilized to assess the cell proliferation; Transwell assay was performed to evaluate the cell invasive ability; and tumor xenografts in nude mice were applied to test the tumor generation. Additionally, the target interactions among lncRNA MEG3, miR-21 and E-cadherin were determined by dual luciferase reporter assay. Finally, RT-PCR and WB were further conducted to verify the regulatory roles among lncRNA MEG3, miR-21 and E-cadherin. RESULTS: The clinical data showed that lncRNA MEG3 and E-cadherin expressions were both declined in carcinoma tissues as compared with their para-carcinoma tissues. Moreover, lncRNA MEG3 and E-cadherin expressions in B16 cells were also higher than those in A375 and A2058 cells. Subsequently, based on the differently expressed lncRNA MEG3 and E-cadherin in these human melanoma cell lines, we chose B16, A375 and A2058 cells for the following experiments. The results demonstrated that lncRNA MEG3 could suppress the tumor growth, tumor metastasis and formation; and meanwhile E-cadherin had the same effects on tumor growth, tumor metastasis and formation. Furthermore, the analysis of Kaplan-Meier curves also confirmed that there was a positive correlation between lncRNA MEG3 and E-cadherin. Ultimately, dual luciferase assays were further used to verify that lncRNA MEG3 could directly target miR-21 which could directly target E-cadherin in turn. Additionally, the data of RT-PCR and WB revealed that knockdown of lncRNA MEG3 in B16 cells inhibited miR-21 expression and promoted E-cadherin expression, but overexpression of lncRNA MEG3 in A375 and A2058 cells presented completely opposite results. CONCLUSION: Our findings indicated that lncRNA MEG3 might inhibit the tumor growth, tumor metastasis and formation of melanoma by modulating miR-21/E-cadherin axis.
ABSTRACT
BACKGROUND Dysregulation of the microRNA (miRNA) network is a typical feature of many cancers. However, the key specific miRNAs involved in uveal melanoma carcinogenesis are largely unknown. MATERIAL AND METHODS RT-qPCR was used to detected miR-652 expression in uveal melanoma tissues and cell lines. miR-652 inhibitor was transfected into uveal melanoma cells to decrease miR-652 expression and determine the biological role of miR-652 by CCK-8 and wound healing assays. Bioinformatic analysis and dual luciferase reporter assay were used to predict and validate the target gene of miR-652. HOXA9 siRNA was transfected into cells to confirm that miR-652 relies on regulation of HOXA9 to regulate cell proliferation and migration. RESULTS RT-qPCR showed that miR-652 was overexpressed in uveal melanoma cell lines (MUM-2B, MEL270) compared with melanocyte cells (ARPE-19). Overexpression of miR-652 was also observed in uveal melanoma compared to paired non-tumor tissues. Downregulation of miR-652 inhibited the cell proliferation ability and migration ability of uveal melanoma cells. Using bioinformatic analysis, HOXA9 was found to be a potential target gene of miR-652. The direct regulation of HOXA9 by miR-652 was experimentally validated in uveal melanoma cells by dual luciferase assay and Western blotting. We also observed that miR-652 promoted HIF-1alpha signaling via repression of HOXA9 in uveal melanoma cells. Silencing of HOXA9 attenuated the miR-652 inhibitor decreased cell growth rate and decreased migration ability in uveal melanoma cells. CONCLUSIONS Our data demonstrate an oncogenic role of miR-652 in uveal melanoma, showing that miR-652 may be a useful biomarker for prediction of prognosis for patients with uveal melanoma.
Subject(s)
Homeodomain Proteins/genetics , Melanoma/genetics , MicroRNAs/genetics , Uveal Neoplasms/genetics , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Homeodomain Proteins/metabolism , Humans , Melanoma/metabolism , MicroRNAs/metabolism , Signal Transduction , Uveal Neoplasms/metabolismABSTRACT
The relation between microRNAs (miRNAs) and malignant melanoma has been demonstrated in previous studies, while there was little research about miR-139-5p and malignant melanoma. The aim of this study is to investigate the ability of miR-139-5p in malignant melanoma cells via the modulation of the PI3K/AKT signaling pathway by targeting IGF1R. MiR-139-5p expression in malignant melanoma tissues and 5 malignant melanoma cell lines was detected. The melanoma cells were transfected with miR-139-5p mimic negative control (NC) sequence, miR-139-5p mimic, IGF1R overexpressed recombinant plasmid NC or IGF1R overexpressed sequence. The expression of Akt signaling pathway-related protein was evaluated. The biological functions in malignant melanoma cells were evaluated by a string of experiments. MiR-139-5p expressed a poor level in tissues and cell lines of malignant melanoma. Overexpressed miR-139-5p suppressed the cell proliferation, migration, and invasion, and contributed to the promoted apoptosis of malignant melanoma cells by decreasing IGF1R. MiR-139-5p down-regulated the IGF1R expression, and IGF1R accelerated the activation of the PI3K/AKT signaling pathway. miR-139-5p reversed the promotive impacts of IGF1R on the PI3K/AKT signaling pathway. The study validates that miR-139-5p could suppress malignant melanoma progression through the repression of the PI3K/AKT signaling pathway by down-regulating IGF1R. Therefore, miR-139-5p could pave a new way for the treatment of malignant melanoma.
Subject(s)
Cell Proliferation/genetics , Melanoma/genetics , MicroRNAs/genetics , Receptor, IGF Type 1/genetics , Adult , Apoptosis/genetics , Cell Line, Tumor , Cell Movement/genetics , Female , Humans , Male , Melanoma/pathology , Middle Aged , Neoplasm Metastasis , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Signal Transduction/geneticsABSTRACT
In nature, sophisticated functional materials are created through hierarchical self-assembly of nanoscale motifs, which has inspired the fabrication of man-made materials with complex architectures for a variety of applications. Herein, a kinetic study on the self-assembly of spindle-like micelles preassembled from polypeptide graft copolymers is reported. The addition of dimethylformamide and, subsequently, a selective solvent (water) can generate a "reactive point" at both ends of the spindles as a result of the existence of structural defects, which induces the "polymerization" of the spindles into nanowires. Experimental results combined with dissipative particle dynamics simulations show that the polymerization of the micellar subunits follows a step-growth polymerization mechanism with a second-order reaction characteristic. The assembly rate of the micelles is dependent on the subunit concentration and on the activity of the reactive points. The present work reveals a law governing the self-assembly kinetics of micelles with structural defects and opens the door for the construction of hierarchical structures with a controllable size through supramolecular step polymerization.