Knock-down of CIAPIN1 sensitizes K562 chronic myeloid leukemia cells to Imatinib by regulation of cell cycle and apoptosis-associated members via NF-κB and ERK5 signaling pathway

Tat-CIAPIN1 Prevents Pancreatic β-Cell Death in hIAPP-Induced RINm5F Cells and T2DM Animal Model

It is well known that the cytokine-induced apoptosis inhibitor 1 (CIAPIN1) protein plays an important role in biological progresses as an anti-apoptotic protein. Human islet amyloid peptide (hIAPP), known as amylin, is caused to pancreatic β-cell death in type 2 diabetes mellitus (T2DM). However, the function of CIAPIN1 protein on T2DM is not yet well studied. Therefore, we investigated the effects of CIAPIN1 protein on a hIAPP-induced RINm5F cell and T2DM animal model induced by a high-fat diet (HFD) and streptozotocin (STZ). The Tat-CIAPIN1 protein reduced the activation of mitogen-activated protein kinase (MAPK) and regulated the apoptosis-related protein expression levels including COX-2, iNOS, Bcl-2, Bax, and Caspase-3 in hIAPP-induced RINm5F cells. In a T2DM mice model, the Tat-CIAPIN1 protein ameliorated the pathological changes of pancreatic β-cells and reduced the fasting blood glucose, body weight and hemoglobin Alc (HbAlc) levels. In conclusion, the Tat-CIAPIN1 protein showed protective effects against T2DM by protection of β-cells via inhibition of hIAPP toxicity and by regulation of a MAPK signal pathway, suggesting CIAPIN1 protein can be a therapeutic protein drug candidate by beneficial regulation of T2DM.

Identification of potential pathways and microRNA-mRNA networks associated with benzene metabolite hydroquinone-induced hematotoxicity in human leukemia K562 cells

Background

Hydroquinone (HQ) is a phenolic metabolite of benzene with a potential risk for hematological disorders and hematotoxicity in humans. In the present study, an integrative analysis of microRNA (miRNA) and mRNA expressions was performed to identify potential pathways and miRNA-mRNA network associated with benzene metabolite hydroquinone-induced hematotoxicity.

Methods

K562 cells were treated with 40 μM HQ for 72 h, mRNA and miRNA expression changes were examined using transcriptomic profiles and miRNA microarray, and then bioinformatics analysis was performed.

Results

Out of all the differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) induced by HQ, 1482 DEGs and 10 DEMs were up-regulated, and 1594 DEGs and 42 DEMs were down-regulated. HQ-induced DEGs were involved in oxidative stress, apoptosis, DNA methylation, histone acetylation and cellular response to leukemia inhibitory factor GO terms, as well as metabolic, Wnt/β-catenin, NF-κB, and leukemia-related pathways. The regulatory network of mRNAs and miRNAs includes 23 miRNAs, 1108 target genes, and 2304 potential miRNAs-mRNAs pairs. MiR-1246 and miR-224 had the potential to be major regulators in HQ-exposed K562 cells based on the miRNAs-mRNAs network.

Conclusions

This study reinforces the use of in vitro model of HQ exposure and bioinformatic approaches to advance our knowledge on molecular mechanisms of benzene hematotoxicity at the RNA level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-022-00556-8.

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) accelerates vascular remodelling via p53 and JAK2-STAT3 regulation in vascular smooth muscle cells

BACKGROUND AND PURPOSE

Abnormal vascular smooth muscle cell (VSMC) proliferation and migration lead to neointima formation, which eventually results in cardiovascular hyperplastic diseases. The molecular mechanisms underlying these cellular processes have not been fully understood. Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) has been identified as an anti-apoptotic molecule, but little is known about its target genes and related pathways in VSMC dysfunction or its clinical implication in neointima formation following vascular injury.

EXPERIMENTAL APPROACH

Determination, using loss/gain-of-function approaches by gene delivery, of whether CIAPIN1 modulates VSMC proliferation, migration and neointima formation and the underlying mechanisms was carried out. Balloon injury or ligation and local delivery of lentivirus were performed on rat or mouse carotid arteries. Rat aortic smooth muscle cells, the primary cell, was used as the model to evaluate the effect of CIAPIN1 on proliferation and migration.

KEY RESULTS

CIAPIN1 was overexpressed in the neointimal region of rat arteries. CIAPIN1 deficiency markedly inhibited injury-induced or ligation-induced intimal hyperplasia and suppressed PDGF-BB-induced VSMC proliferation, migration and cell cycle progression, while overexpression promoted proliferation, migration and neointima formation. CIAPIN1 negatively regulated Tp53 transcription, which promoted cell cycle progression and migration via cyclin E1-CDK2/pRb/PCNA and the MMP2 pathway. CIAPIN1 also increased JAK2 expression, enhancing JAK2 and STAT3 phosphorylation by vascular injury, which forced phenotypic switching from contractile to synthetic state in injured arteries.

CONCLUSIONS AND IMPLICATIONS

These findings provide new insights into the mechanism by which CIAPIN1 regulates vascular remodelling and suggest a novel therapeutic target for treating vascular proliferative diseases.

Inhibition of miR-322-5p Protects Cardiac Myoblast Cells Against Hypoxia-Induced Apoptosis and Injury Through Regulating CIAPIN1

ABSTRACT

Hypoxia leads to insufficient supply of blood and nutrients, which is major incentive for cardiomyocyte injury and apoptosis. Previous studies reported the regulation effects of microRNAs (miRNAs) in myocardial infarction, whereas function and molecular mechanisms of miR-322-5p were still unclear. Therefore, our study focused on the biological role of miR-322-5p in hypoxia-induced cardiac myoblast cells apoptosis and injury. The expression levels of miR-322-5p and cytokine-induced apoptosis inhibitor 1 (CIAPIN1) were measured by real-time quantitative polymerase chain reaction in cardiac myoblast cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT), lactic dehydrogenase, and flow cytometry assays were performed to examine proliferation, injury, and apoptosis of cardiac myoblast cells, respectively. The protein expression levels were evaluated with western blot assay. The relationship between miR-322-5p and CIAPIN1 was confirmed by dual-luciferase reporter analysis. We found that miR-322-5p level was increased in cardiac myoblast cells exposed to hypoxia. In addition, miR-322-5p silencing could weaken injury and apoptosis in cardiac myoblast cells induced by hypoxia; meanwhile, inhibition of miR-322-5p activation of phosphatidylinositol-3 kinases (PI3K)/protein kinase B (AKT) signal pathway. Besides, CIAPIN1 was a target mRNA of miR-322-5p based on bioinformatics prediction. CIAPIN1 knockdown reversed the effects of miR-322-5p silencing on hypoxic cardiac myoblast cells. Suppression of miR-322-5p protected cardiac myoblast cells against hypoxia-induced injury and apoptosis through regulation of CIAPIN1 expression and PI3K/AKT signal pathway.

Effect of Ocimum sanctum extract on leukemic cell lines: A preliminary in-vitro study

Background:

Surge of cancer incidence, effects of chemotherapeutic agents and their cost and reduced survival and responsiveness to treatment have led to shift of attention of researchers toward herbal remedies to look for newer dimension in cancer therapy. Ocimum sanctum, Holy Basil or Tulsi, holiest herb well used in the Indian household, has drawn much attention toward its various health benefits, especially anti-cancer property. The present study was carried out to evaluate the cytotoxic effect of O. sanctum on leukemic cell lines K562.

Materials and Methods:

Dry and aqueous extracts of two types of Tulsi leaves (Rama Tulsi and Krishna Tulsi) were evaluated for a dose-dependent cytotoxicity and anti-proliferative against K562 cell lines, leukoerythroid progenitor leukemic cell lines by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Half-maximal inhibitory concentration was evaluated for each of the extracts.

Results:

Both dry and aqueous extracts of both types of Tulsi leaves demonstrated a significant amount of cytotoxicity against the studied cell lines.

Conclusion:

This being preliminary study, we propose the initial finding of cytotoxic abilities of the herb against the leukemic cell lines and recommend a more detailed evaluation of the herb and its components.

Transduced Tat-CIAPIN1 reduces the inflammatory response on LPS- and TPA-induced damages

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1), known as an anti-apoptotic and signal-transduction protein, plays a pivotal role in a variety of biological processes. However, the role of CIAPIN1 in inflammation is unclear. We investigated the protective effects of CIAPIN1 in lipopolysaccharide (LPS)-exposed Raw 264.7 cells and against inflammatory damage induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in a mouse model using cell-permeable Tat-CIAPIN1. Transduced Tat-CIAPIN1 significantly reduced ROS production and DNA fragmentation in LPS-exposed Raw 264.7 cells. Also, Tat-CIAPIN1 inhibited MAPKs and NF-κB activation, reduced the expression of Bax, and cleaved caspase-3, COX-2, iNOS, IL-6, and TNF-α in LPS-exposed cells. In a TPA-induced animal model, transduced Tat-CIAPIN1 drastically decreased inflammation damage and inhibited COX-2, iNOS, IL-6, and TNF-α expression. Therefore, these findings suggest that Tat-CIAPIN1 might lead to a new strategy for the treatment of inflammatory skin disorders.

Re-Evaluating the Mechanism of Action of α,β-Unsaturated Carbonyl DUB Inhibitors b-AP15 and VLX1570: A Paradigmatic Example of Unspecific Protein Cross-linking with Michael Acceptor Motif-Containing Drugs

Deubiquitinating enzymes (DUBs) are a growing target class across multiple disease states, with several inhibitors now reported. b-AP15 and VLX1570 are two structurally related USP14/UCH-37 inhibitors. Through a proteomic approach, we demonstrate that these compounds target a diverse range of proteins, resulting in the formation of higher molecular weight (MW) complexes. Activity-based proteome profiling identified CIAPIN1 as a submicromolar covalent target of VLX1570, and further analysis demonstrated that high MW complex formation leads to aggregation of CIAPIN1 in intact cells. Our results suggest that in addition to DUB inhibition, these compounds induce nonspecific protein aggregation, providing molecular explanation for general cellular toxicity.

Biochanin A protects against PM2.5-induced acute pulmonary cell injury by interacting with the target protein MEK5

Epidemiological studies have shown that exposure to ambient fine particulate matter (PM_2.5) is associated with an increased risk for cardiopulmonary diseases. The MEK5/ERK5 and NF-κB signaling pathways are closely related to the regulation of acute pulmonary cell injury (APCI) and may play an important role in the underlying pathophysiological mechanisms. Related studies have shown that Biochanin A (BCA) effectively interferes with APCI, but the underlying mechanism through which this occurs is not fully understood. Previously, based on proteomic and bioinformatic research, we found the indispensable role of MEK5 in mediating remission effects of BCA against PM_2.5-induced lung toxicity. Therefore, using A549 adenocarcinoma human alveolar basal epithelial cells (A549 cells), we combined western blot and qRT-PCR to study the protective signaling pathways induced by BCA, indicating that MEK5/ERK5 and NF-κB are both involved in mediating APCI in response to PM_2.5, and MEK5/ERK5 positively activated NF-κB and its downstream cellular regulatory factors. BCA significantly suppressed PM_2.5-induced upregulation of MEK5/ERK5 expression and phosphorylation and activation of NF-κB. Furthermore, due to the specificity of the MEK5/ERK5 protein structure, the binding sites and binding patterns of BCA and MEK5 were analyzed using molecular docking correlation techniques, which showed that there are stable hydrogen bonds between BCA and the PB1 domain of MEK5 as well as its kinase domain. BCA forms a stable complex with MEK5, which has potential effects on MEKK2/3-MEK5-ERK5 ternary interactions, p62/αPKC-mediated NF-κB regulation, and inhibition of MEK5 target protein phosphorylation. Therefore, our study suggests that MEK5 is an important regulator of intracellular signaling of APCI in response to PM_2.5 exposure. BCA may exert anti-APCI activity by targeting MEK5 to inhibit activation of the MEK5/ERK5/NF-κB signaling pathway.

Downregulation of miR‑16 protects H9c2(2‑1) cells against hypoxia/reoxygenation damage by targeting CIAPIN1 and regulating the NF‑κB pathway

The aim of the present study was to determine the function of microRNA‑16 (miR‑16) in myocardial hypoxia/reoxygenation (H/R)‑induced cardiomyocyte injury and the possible mechanism underlying its involvement. An H/R model was constructed using H9c2(2‑1) cells in vitro. The results of reverse transcription‑quantitative PCR demonstrated that the expression levels of miR‑16 were significantly upregulated in H9c2(2‑1) cells in the H/R group compared with the sham group (1.53±0.09 vs. 1.0±0.08; P=0.0019). Cell Counting Kit‑8 assays revealed that the relative proliferative ability of H9c2(2‑1) cells was significantly decreased in the H/R + negative control (NC) group compared with the sham group (0.53±0.05 vs. 1.0±0.08; P=0.00005). Upregulation of miR‑16 using miR‑16 mimics further decreased the proliferative ability of cells (0.31±0.03 vs. 0.53±0.05; P=0.0097), whereas downregulation of miR‑16 using an miR‑16 inhibitor increased the proliferative ability of cells compared with the H/R+NC group (0.89±0.08 vs. 0.53±0.05; P=0.000385). Flow cytometric analysis found that the apoptotic rate of H9c2(2‑1) cells was increased significantly following H/R compared with the sham group (25.86±2.62% vs. 9.29±0.82%, P=0.000014). Upregulation of miR‑16 further increased the apoptotic rate (38.62±2.04% vs. 25.86±2.62%; P=0.000099), whereas downregulation of miR‑16 decreased the apoptotic rate compared with the H/R+NC group (15.14±0.92% vs. 25.86±2.62%; P=0.000343). miR‑16 directly bound to the 3'‑untranslated region of cytokine‑induced apoptosis inhibitor 1 (CIAPIN1) and negatively modulated CIAPIN1 expression. Overexpression of CIAPIN1 reversed the changes in the expression of apoptosis‑associated proteins caused by H/R. Western blot analysis revealed that the levels of phospho‑(p‑)nuclear factor‑κB (NF‑κB) and p‑NF‑κB inhibitor α (IκBα) were upregulated following H/R (1.82±0.11 vs. 1.0±0.08; P=0.000152; and 1.77±0.07 vs. 1.0±0.00; P=0.000024, respectively), and these changes were further enhanced when miR‑16 expression levels were increased (3.10±0.14 vs. 1.82±0.11; P=0.000006; and 2.19±0.10 vs. 1.77±0.07; P=0.0017, respectively). Downregulation of miR‑16 exhibited the opposite effect on p‑NF‑κB and p‑IκBα expression levels. The present study illustrates that downregulation of miR‑16 may protect against H/R‑induced injury partially by targeting CIAPIN1 and the NF‑κB signaling pathway.

Therapeutic Delivery of miR-143 Targeting Tumor Metabolism in Poorly Differentiated Thyroid Cancer Xenografts and Efficacy Evaluation Using 18F-FDG MicroPET-CT

Poorly differentiated thyroid carcinoma cells tend to be more aggressive and show enhanced glucose uptake which could be exploited for anti-cancer strategy. Previously, we identified hexokinase 2 (HK2) as a direct target of miR-143. In our current study, the effects of miR-143 on glucose metabolism and tumor biological behavior were investigated in FTC-133 cells which is a poorly differentiated thyroid carcinoma (PDTC). Additionally, tumor-bearing mice xenografts of PDTC were constructed, with encapsulated miR-143 agomir being administered intravenously. 18F-FDG microPET-CT scanning was used for the evaluation of therapeutic efficacy. The tumor-restrained effect of miR-143 was demonstrated in PDTC. Furthermore, microPET/CT imaging exhibited a reduction of 18F-FDG uptake in tumors, corresponding to the downregulated expression of HK2 in tissues. In summary, our results suggest that miR-143 can be an alternative treatment for PDTC and the specific assessment of therapeutic response to miR-143 can be achieved by 18F-FDG microPET/CT in advanced thyroid carcinoma xenografts.

CIAPIN1 Targeted NHE1 and ERK1/2 to Suppress NSCLC Cells' Metastasis and Predicted Good Prognosis in NSCLC Patients Receiving Pulmonectomy

Objective

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) acts as a downstream effector of the receptor tyrosine kinase-Ras signaling pathway and has been reported as a candidate tumor suppressor gene in various cancers. Our current study was aimed at investigating the prognostic impact of CIAPIN1 on Non-Small-Cell Lung Carcinoma (NSCLC) patients and the effect of CIAPIN1 on NSCLC A549 cells' metastasis.

Methods

Western blot analysis was applied to detect CIAPIN1 expression; Kaplan-Meier survival analysis was used to evaluate the effect of CIAPIN1 on NSCLC patients' prognosis. Wound healing assay, Transwell chamber invasion analysis, and tumorigenicity assay in BALB/c nude mice were used to measure the metastasis potential of A549 cells.

Results

We found that CIAPIN1 overexpression indicated good survival duration during the follow-up period. CIAPIN1 overexpression inhibited the migration, invasion, MMPs, and EMT-associated markers in A549 cells. Further, NHE1 (Na+/H+ exchanger 1) expression and ERK1/2 phosphorylation decreased along with CIAPIN1 upregulation. Importantly, treating A549 cells with CIAPIN1 overexpression with the NHE1-specific inhibitor, Cariporide, further inhibited the metastatic capacity, MMP expression, EMT-associated markers, and phosphorylated ERK1/2. Treatment with the MEK1-specific inhibitor, PD98059, induced nearly the same suppression of CIAPIN1 overexpression-dependent metastatic capacity, MMP expression, and EMT-associated markers as was observed with Cariporide. Further, Cariporide and PD98059 exert synergistical suppression of A549 cells' metastatic capacity.

Conclusion

Thus, the current results implied a potential management by which CIAPIN1 upregulation may have a crucial effect on the suppression of NSCLC, indicating that overexpression of CIAPIN1 might serve as a combination with chemotherapeutical agents in NSCLC therapy.

Impact of ERK5 on the Hallmarks of Cancer

Extracellular signal-regulated kinase 5 (ERK5) belongs to the mitogen-activated protein kinase (MAPK) family that consists of highly conserved enzymes expressed in all eukaryotic cells and elicits several biological responses, including cell survival, proliferation, migration, and differentiation. In recent years, accumulating lines of evidence point to a relevant role of ERK5 in the onset and progression of several types of cancer. In particular, it has been reported that ERK5 is a key signaling molecule involved in almost all the biological features of cancer cells so that its targeting is emerging as a promising strategy to suppress tumor growth and spreading. Based on that, in this review, we pinpoint the hallmark-specific role of ERK5 in cancer in order to identify biological features that will potentially benefit from ERK5 targeting.

Novel Application of Radotinib for the Treatment of Solid Tumors via Natural Killer Cell Activation

Radotinib (Supect™) was developed to treat chronic myeloid leukemia (CML) as a BCR-ABL1 tyrosine kinase inhibitor (TKI). Other TKIs, including imatinib and nilotinib, were also developed for treatment of CML, and recent studies were increasing about the therapeutic effects of other TKIs on solid tumors. However, the effect of radotinib on solid tumors has not yet been investigated. In this study, radotinib killed CML cell line K562 directly; however, radotinib did not enhance NK cell cytotoxicity against K562 cells. Because K562 is known as a Fas-negative cell line, we investigated whether radotinib could regulate cell cytotoxicity against various Fas-expressing solid cancer cell lines. Radotinib dramatically increased NK cell cytotoxicity against various Fas-expressing solid cancer cells, including lung, breast, and melanoma cells. Additionally, the efficiency of radotinib-enhanced cytotoxicity was lower in Fas siRNA-transfected cells than in negative controls, suggesting that Fas signaling might be involved in the radotinib-enhanced NK cell cytotoxicity. This study provides the first evidence that radotinib could be used as an effective and strong therapeutic to treat solid tumors via upregulation of NK cell cytotoxicity, suggesting that radotinib has indirect killing mechanisms via upregulation of antitumor innate immune responses as well as direct killing activities for CML cells.

Inhibition of miR-182-5p protects cardiomyocytes from hypoxia-induced apoptosis by targeting CIAPIN1

Myocardial infarction (MI), a type of ischemic heart disease, is generally accompanied by apoptosis of cardiomyocytes. MicroRNAs play the vital roles in the development and physiology of MI. Here, we established a downregulation model of miR-182-5p in H9c2 cells under hypoxic conditions to investigate the potential molecular mechanisms for miR-182-5p in hypoxia-induced cardiomyocyte apoptosis (HICA). RT-qPCR indicated that miR-182-5p levels exhibit a time-dependent increase in the rate of apoptosis induced by hypoxia. The results from the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactate dehydrogenase) assays indicated that cardiomyocyte injury noticeably increased after exposure to hypoxia. Meanwhile, hypoxia dramatically increased the apoptosis rate [which was reflected in the results from the annexin V – propidium iodide (PI) assay], enhanced caspase-3 activity, and reduced the expression of Bcl-2. Downregulation of miR-182-5p can significantly reverse hypoxia-induced cardiomyocyte injury or apoptosis. Importantly, bioinformatic analysis and dual-luciferase reporter assay revealed that CIAPIN1 (cytokine-induced apoptosis inhibitor 1) was a direct functional target of miR-182-5p, and that inhibition of miR-182-5p can lead to an increase in CIAPIN1 expression at both the mRNA and protein levels. Furthermore, the knockdown of CIAPIN1 with small interfering RNAs (siRNAs) efficiently abolished the protective effects of miR-182-5p inhibitor on HICA, demonstrating that miR-182-5p plays a pro-apoptotic role in cardiomyocytes under hypoxic conditions by downregulating CIAPIN1. Collectively, our results demonstrate that miR-182-5p may serve an underlying target to prevent cardiomyocytes from hypoxia-induced injury or apoptosis.

Targeting the Extracellular Signal-Regulated Kinase 5 Pathway to Suppress Human Chronic Myeloid Leukemia Stem Cells

Tyrosine kinase inhibitors (TKi) are effective against chronic myeloid leukemia (CML), but their inefficacy on leukemia stem cells (LSCs) may lead to relapse. To identify new druggable targets alternative to BCR/ABL, we investigated the role of the MEK5/ERK5 pathway in LSC maintenance in low oxygen, a feature of bone marrow stem cell niches. We found that MEK5/ERK5 pathway inhibition reduced the growth of CML patient-derived cells and cell lines in vitro and the number of leukemic cells in vivo. Treatment in vitro of primary CML cells with MEK5/ERK5 inhibitors, but not TKi, strikingly reduced culture repopulation ability (CRA), serial colony formation ability, long-term culture-initiating cells (LTC-ICs), and CD26-expressing cells. Importantly, MEK5/ERK5 inhibition was effective on CML cells regardless of the presence or absence of imatinib, and did not reduce CRA or LTC-ICs of normal CD34+ cells. Thus, targeting MEK/ERK5 may represent an innovative therapeutic approach to suppress CML progenitor/stem cells.

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ERK5 is constitutively active in chronic myeloid leukemia (CML) cells

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ERK5 pathway inhibition reduces the growth of CML cells in vitro and in vivo

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ERK5 pathway inhibition strikingly reduces CML progenitor/stem cell maintenance

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The combination of ERK5i with imatinib reduces the expression of stem cell proteins

Hsa-miRNA-143-3p Reverses Multidrug Resistance of Triple-Negative Breast Cancer by Inhibiting the Expression of Its Target Protein Cytokine-Induced Apoptosis Inhibitor 1 In Vivo

PURPOSE

Multidrug resistance (MDR) remains a major obstacle in the treatment of triple-negative breast cancer (TNBC) with conventional chemotherapeutic agents. A previous study demonstrated that hsa-miRNA-143-3p plays a vital role in drug resistance of TNBC. Downregulation of hsa-miRNA-143-3p upregulated the expression of its target protein cytokine-induced apoptosis inhibitor 1 (CIAPIN1) in order to activate MDR, while upregulation of hsa-miRNA-143-3p effectively enhances the sensitivity of drug-resistant TNBC cells to chemotherapeutics. The present study aimed to further verify these findings in vivo.

METHODS

We established a hypodermic tumor nude mice model using paclitaxel-resistant TNBC cells. We expressed ectopic hsa-miRNA-143-3p under the control of a breast cancer-specific human mammaglobin promoter that guided the efficient expression of exogenous hsa-miRNA-143-3p only in breast cancer cells. Thereafter, we overexpressed hsa-miRNA-143-3p in xenografts using a recombinant virus system and quantified the expression of hsa-miRNA-143-3p, CIAPIN1 protein, and proteins encoded by related functional genes by western blot.

RESULTS

We successfully completed the prospective exploration of the intravenous virus injection pattern from extensive expression to targeted expression. The overexpression of hsa-miRNA-143-3p significantly alleviated chemoresistance of TNBC by inhibiting viability. In addition, we observed that the expression of CIAPIN1 as a hsa-miRNA-143-3p target protein was remarkably decreased.

CONCLUSION

We partly illustrated the mechanism underlying the hsa-miRNA-143-3p/CIAPIN1 drug resistance pathway. HsamiRNA-143-3p as a tumor suppressive microRNA may be a novel target to effectively reverse MDR of TNBC in vivo.

6'-Hydroxy Justicidin B Triggers a Critical Imbalance in Ca2+ Homeostasis and Mitochondrion-Dependent Cell Death in Human Leukemia K562 Cells

Justicia procumbens (J. procumbens) is a traditional Chinese herbal medicine which was used for the treatment of fever, pain, and cancer. A compound 6'-hydroxy justicidin B (HJB) isolated from J. procumbens exhibits promising biological properties. However, the mechanism of action and the in vivo behavior of HJB remain to be elucidated. In this study, we investigated the mechanism of action of HJB on human leukemia K562 cells and its pharmacokinetic properties in rats. The results demonstrated that HJB significantly inhibited the proliferation of K562 cells and promoted apoptosis. Besides, HJB resulted in decreased mitochondrial membrane potential deltaPSIm, increased the level of the calcium homeostasis regulator protein TRPC6 and cytosolic calcium. The activity of caspase-8, caspase-9 and the expression of p53 were significantly increased after treatment with HJB. Additionally, HJB has rapid absorption rate and relative long elimination t1/2, indicating a longer residence time in vivo. The results indicate that HJB inhibited the proliferation of K562 cells and induced apoptosis by affecting the function of mitochondria and calcium homeostasis to activate the p53 signaling pathway. The pharmacokinetic study of HJB suggested it is absorbed well and has moderate metabolism in vivo. These results present HJB as a potential novel alternative to standard human leukemia therapies.

Extracellular Signal-Regulated Kinase 5 is Required for Low-Concentration H2O2-Induced Angiogenesis of Human Umbilical Vein Endothelial Cells

Background. The aim of this study was to assess the effects of low concentrations of H₂O₂ on angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro and explore the underlying mechanisms. Methods. HUVECs were cultured and stimulated with different concentrations of H₂O₂. Flow cytometric analysis was used to select an optimal concentration of H₂O₂ for the following experiments. Cell proliferation, migration, and tubule formation were evaluated by Cell Counting Kit-8 (CCK-8) assays, scratch wound assays, and Matrigel tubule formation assays, respectively. For gain and loss of function studies, constitutively active MEK5 (CA-MEK5) and ERK5 shRNA lentiviruses were used to activate or knock down extracellular signal-regulated kinase 5 (ERK5). Results. We found that low concentrations of H₂O₂ promoted HUVECs proliferation, migration, and tubule formation. ERK5 in HUVECs was significantly activated by H₂O₂. Enhanced ERK5 activity significantly amplified the proangiogenic effects of H₂O₂; in contrast, ERK5 knock-down abrogated the effects of H₂O₂. Conclusions. Our results confirmed that low concentrations of H₂O₂ promoted HUVECs angiogenesis in vitro, and ERK5 is an essential mediator of this process. Therefore, ERK5 may be a potential therapeutic target for promoting angiogenesis and improving graft survival.