[Prognostic value of the Second Revision of the International Staging System in patients with newly diagnosed transplant-eligible multiple myeloma].

Objective: To verify the predictive value of the Second Revision of the International Staging System (R2-ISS) in newly diagnosed patients with multiple myeloma (MM) who underwent first-line autologous hematopoietic stem cell transplantation (ASCT) in a new drug era in China. Methods: This multicenter retrospective cohort study enrolled patients with newly diagnosed MM from three centers in China (Beijing Chao-Yang Hospital, Capital Medical University; the First Affiliated Hospital, Sun Yat-Sen University, and the Second Affiliated Hospital of Naval Medical University) from June 2008 to June 2018. A total of 401 newly diagnosed patients with MM who were candidates for ASCT were enrolled in this cohort, all received proteasome inhibitor and/or immunomodulator-based induction chemotherapy followed by ASCT. Baseline and follow-up data were collected. The patients were regrouped using R2-ISS. Progression-free survival (PFS) and overall survival (OS) were analyzed. The Kaplan-Meier method was used to analyze the survival curve and two survival curves were compared using the log-rank test. Cox regression analysis were performed to analyze the relationship between risk factors and survival. Results: The median age of the patients was 53 years (range 25-69 years) and 59.5% (240 cases) were men. Newly diagnosed patients with renal impairment accounted for 11.5% (46 cases). According to Revised-International Staging System (R-ISS), 74 patients (18.5 %) were diagnosed with stage Ⅰ, 259 patients (64.6%) with stage Ⅱ, and 68 patients (17.0%) with stage Ⅲ. According to the R2-ISS, the distribution of patients in each group was as follows: 50 patients (12.5%) in stage Ⅰ, 95 patients (23.7%) in stage Ⅱ, 206 patients (51.4%) in stage Ⅲ, and 50 patients (12.5%) in stage Ⅳ. The median follow-up time was 35.9 months (range, 6-119 months). According to the R2-ISS stage, the median PFS in each group was: 75.3 months for stage Ⅰ; 62.0 months for stage Ⅱ, 39.2 months for stage Ⅲ, and 30.3 months for stage Ⅳ; and the median OS was not reached, 86.6 months, 71.6 months, and 38.5 months, respectively. There were statistically significant differences in PFS and OS between different groups (both P<0.001). Multivariate Cox regression analysis showed that stages Ⅲ and Ⅳ of the R2-ISS were independent prognostic factors for PFS (HR=2.37, 95%CI 1.30-4.30; HR=4.50, 95%CI 2.35-9.01) and OS (HR=4.20, 95%CI 1.50-11.80; HR=9.53, 95%CI 3.21-28.29). Conclusions: The R2-ISS has significant predictive value for PFS and OS for transplant-eligible patients with MM in the new drug era. However, the universality of the R2-ISS still needs to be further verified in different populations.

Exosomes Derived from Endothelial Cells Inhibit Neointimal Hyperplasia Induced by Carotid Artery Injury in Rats via ROS-NLRP3 Inflammasome Pathway.

This study attempted to investigate whether exosomes derived from rat endothelial cells (EC-Exo) attenuate intimal hyperplasia after balloon injury using hematoxylin and eosin staining, immunohistochemistry, immunofluorescence staining, Evans blue staining, and Western blotting. The results indicated that EC-Exo inhibited intimal hyperplasia in the carotid artery after balloon injury, promoted re-endothelialization, and reduced vascular inflammation and ROS-NLRP3-mediated cell pyroptosis. Thus, EC-Exo can inhibit neointimal hyperplasia after carotid artery injury in rats presumably by inhibiting the ROS-NLRP3 inflammasome and phenotypic transformation of vascular smooth muscle cells.

[Prognostic significance of immunoparesis in newly diagnosed multiple myeloma patients who achieved deep response].

Objective: To evaluate the effect of immune status on disease progression in patients with newly diagnosed multiple myeloma (NDMM) achieving deep response. Methods: Clinical data of 125 NDMM patients at Beijing Chaoyang Hospital from August 2015 to February 2020 were retrospectively analyzed who achieved very good partial response (VGPR) or better after front-line treatment. The immune status and its influence on progression-free survival (PFS) were analyzed. Results: (1) All patients received novel drug regimens, and 50.4% (63/125) patients followed by autologous stem cell transplantation (ASCT). The rate of complete response (CR) as best efficacy was 89.6%, in which 66.4% achieved CR and MRD negativity tested by second generation flow cytometry. (2) Cox multivariate analysis suggested that persistent severe immunoparesis 3 months and 6 months since the best response was an independent poor prognostic factor for PFS. (3) The 3-year PFS rate in the severe immunoparesis group was significantly lower than that in the control group (41.3% vs. 64.4%, P=0.021). (4) The 3-year PFS rates in patients with persistent severe immunoparesis at 3 months or 6 months were significantly lower (30.0% vs. 63.5%, P<0.001; 16.4% vs. 63.8%, P<0.001 respectively). (5) Even in those achieving CR and negative MRD, the 3-year PFS rate when severe immunoparesis lasted 6 months was significantly lower (22.2% vs. 83.2%, P=0.005). Conclusion: The immune status in NDMM patients achieving deep response is closely related to survival. Persistent severe immunoparesis indicates early progression of the disease.

[The prognostic relationship between CD56 expression and newly diagnosed multiple myeloma].

Objective: To evaluate the prognostic value of CD56 expression in newly diagnosed MM (NDMM). Methods: A total of 332 NDMM patients were enrolled in Beijing Chaoyang Hospital, Capital Medical University from January 1, 2011 to January 1, 2021, with a median age of 60 years and a male to female ratio of 1.2∶1. CD56 expression on myeloma cells was detected by flow cytometry before induction therapy. Overall survival (OS) and progression-free survival (PFS) data were collected. In order to reduce the confounding factors, the propensity score matching technique was used to match CD56 positive versus negative patients at a ratio of 1∶1. Results: Among 332 patients, CD56 positivity rate was 65.1% (216/332). Patients with CD56 expression had significantly longer median OS (58.4 vs. 43.1 months, P=0.024) and PFS (28.7 vs. 24.1 months, P=0.013) than those with negative CD56. Univariate Cox proportional hazards regression analyses showed that CD56 expression was positively correlated with OS (HR=0.644, 95%CI 0.438-0.947, P=0.025) and a favorable prognostic factor for PFS (HR=0.646, 95%CI 0.457-0.913,P=0.013). The favorable effect of CD56 expression on PFS was confirmed in multivariate analysis (HR=0.705, 95%CI 0.497-0.998, P=0.049), but OS was not affected (P>0.05).In the propensity score matching analysis, 194 patients with 97 in each group were identified. CD56 positivity consistently predicted longer PFS (34.2 vs.25.1 months, P=0.047), but not OS (63.4 vs.43.1 months, P=0.056). Conclusion: These results demonstrate that CD56 expression is a favorable prognostic factor for PFS of newly diagnosed MM patients.

[Controversies on the diagnosis and treatment of relapsed/refractory multiple myeloma].

With the widely usage of proteasome inhibitors, immunomodulating agents, monoclonal antibodies and autologous stem cell transplantation in the first line, most of multiple myeloma(MM) patients achieved high response rate and prolonged the survival period, but most of MM patients will relapse eventually. There are a lot of unmet needs for the management of relapse and refractory myeloma (RRMM). Although there are several guidelines for the diagnosis and treatment of RRMM, but doctors often find some controversies in clinical practice. The controversies will be discussed in this paper expected to guide the practice of younger doctors.

[Clinical analysis of multiple myeloma with second primary malignancies and multiple myeloma secondary to malignancies].

Objective: To compare the clinical characteristics and survival outcomes of multiple myeloma (MM) with second primary malignancies (SPMs) and MM secondary to malignancies. Methods: The clinical data of MM patients diagnosed and treated in Beijing Chaoyang Hospital, Capital Medical University from January 2002 to January 2021 were included. The patients were divided into two groups: MM with SPMs group and MM secondary to malignancies group. The gender, age at first diagnosis, classification, stage, type of combined malignant tumor and the treatment were analyzed. The clinical characteristics and survival differences were compared between the two groups. Results: There were 20 patients in the MM with SPMs group, 9 males and 11 females, aged [M(Q1,Q3)] 61.5(56.8, 68.0)years, and the overall survival (OS) was 49.5(32, 58) months, while the time to death from secondary tumor was 12(4,21)months. There were 29 patients in the MM secondary to malignancies group, 13 males and 16 females, aged 64.0(57.0, 71.0)years, and the OS was 97(61, 171) months, while the time to death from secondary MM was 32(18, 47) months. The time from patients diagnosed with MM to SPMs was 37(18, 50) months, which was significantly earlier than that of MM secondary to malignancies [53(31,117) months](P=0.016). The type of tumor was also different between the two groups (P<0.001). In the group of MM with SPMs, the most common type of SPMs was hematopoietic malignancies (12/20, 60.0%), whereas in the group of MM secondary to malignancies, MM was most often secondary to genitourinary malignancies (13/29, 44.8%) (P<0.001). Conclusions: Both MM with SPMs and MM secondary to malignancies can affect the survival of patients. Secondary hematological malignancies account for a high proportion of the second tumors in MM patients, while genitourinary malignancies account for a high proportion of malignant tumors associated with MM.

[The prognostic value of dynamic minimal residual disease after autologous hematopoietic stem cell transplantation in patients with multiple myeloma in novel-agent era].

Objective: To investigate the clinical prognostic value of dynamic minimal residual disease (MRD) after autologous hematopoietic stem cell transplantation (AHSCT) in patients with multiple myeloma (MM). Methods: Patients with MM who underwent AHSCT in Beijing Chao-Yang Hospital from February 2016 to December 2019 were enrolled in this study. All the patients in the study had complete baseline data at the diagnosis. AHSCT was performed after induction chemotherapy. Response evaluation was performed after induction therapy. All the patients were assessed at approximately 100 days after AHSCT. Bone marrow MRD by NGF was performed every three months and dynamically monitored for at least 12 months. All the patients were divided into different groups according to cytogenetics and MRD status. Survivals in different groups were analyzed by IBM SPSS 22.0 statistical software. Results: A total of 150 patients with MM were enrolled in this study at last, including 66 patients in the cytogenetic standard risk group and 84 patients in the cytogenetic high-risk group. The median age was 54 years (range 30-68 years) and 87 male patients (58.0%) was in the study. The median follow-up was 36 months (range 16-72 months). Patients in the standard-risk group had better clinical prognosis than those in the high-risk group [median PFS in the standard-risk group was not achieved, and median PFS in the high-risk group was 45 months (P<0.001); median OS of both groups was not reached, and the estimated 3-year OS rate of the standard-risk group and the high-risk group was 95.2% and 78.9%, respectively (P=0.001)]. According to MRD status of patients, patients in each group were divided into three subgroups: persistent positive (Ppos), transient negative (Tneg) and persistent negative (Pneg). The median OS and median PFS of all subgroups in the standard-risk group was not reached (P=0.324 and P=0.086). In high-risk group, the median OS of MRD Pneg subgroup was not reached, and the estimated 3-year OS rate was 100%; The median OS of MRD Ppos subgroup was 52 months, and MRD Tneg subgroup only 31 months (P=0.002); the median PFS of MRD Pneg group was not reached, and the estimated 3-year PFS rate was 85.4%; median PFS of MRD Ppos subgroup was 40 months, and MRD Tneg subgroup only 17 months (P=0.001). Conclusions: MRD Pneg might overcome the adverse prognosis of MM patients with high-risk cytogenetics. However, MRD Tneg might be a poor prognostic factor for the patients with cytogenetic high-risk MM.

Identifying a Generic and Detrimental Role of Fano Resonance in Spin Generation in Semiconductor Nanostructures.

Fano resonance is a fundamental physical process that strongly affects the electronic transport, optical, and vibronic properties of matter. Here, we provide the first experimental demonstration of its profound effect on spin properties in semiconductor nanostructures. We show that electron spin generation in InAs/GaAs quantum-dot structures is completely quenched upon spin injection from adjacent InGaAs wetting layers at the Fano resonance due to coupling of light-hole excitons and the heavy-hole continuum of the interband optical transitions, mediated by an anisotropic exchange interaction. Using a master equation approach, we show that such quenching of spin generation is robust and independent of Fano parameters. This work therefore identifies spin-dependent Fano resonance as a universal spin loss channel in quantum-dot systems with an inherent symmetry-breaking effect.

[Analysis of the clinical effects and outcome of patients with double-hit high-risk multiple myeloma].

Objective: To compare the clinical features, clinical efficacy, and prognosis of patients with double-hit and non-double-hit high-risk multiple myeloma (MM) and explored the clinical significance of high-risk cell karyotype in MM development. Methods: The clinical data of 73 high-risk MM patients admitted to the Department of Hematology of Fujian Provincial Hospital from January 2011 to February 2019 were retrospectively analyzed. Interphase fluorescence in situ hybridization was used to detect their karyotypes. Based on mSMART 3.0 risk stratification, we divided the patients into a double-hit group (28 cases) and a non-double-hit group (45 cases). Results: Fifteen patients in the double-hit group and 26 in the non-double-hit group received bortezomib-based chemotherapy. The median progression-free survival (PFS) in the double-hit and the non-double-hit groups was 8.0 months and 22.0 months, and the median overall survival (OS) was 10.0 months and not reached, respectively. Ten patients in the double-hit group and 12 in the non-double-hit group received bortezomib combined with lenalidomide (RVD) chemotherapy. The median PFS in the double-hit group and the non-double-hit group was 12.0 months and 24.0 months, and the median OS was 14.0 months and not reached, correspondingly. Both the PFS and OS of the double-hit group were significantly shorter than those of the non-double-hit group (P<0.05). Univariate analysis results indicated that cytogenetic abnormalities, revised-international staging system (R-ISS), ß2 microglobulin, and calcium had significant effects on PFS in high-risk MM patients (P<0.05). The cytogenetic abnormalities, R-ISS, and ß2 microglobulin were associated with OS in high-risk MM patients (P=0.001). Multivariate Cox regression analysis showed that the cytogenetic grouping was an independent prognostic factor for OS and PFS in high-risk MM patients. The risk of disease progression was 3.160 times (95% CI: 1.364-7.318) and the risk of death was 2.966 times higher (95%CI: 1.205-7.306) in the double-hit group than those in the non-double-hit group. Calcium was an independent risk factor for PFS in the high-risk MM patients. Notably, the risk of disease progression in patients with calcium levels≥ 2.75 mmol/L was 2.667 times higher than that in patients with calcium<2.75 mmol/L (95% CI: 1.209-5.883). Conclusions: Double-hit patients are a highly specific group with worse high-risk MM prognosis. In such patients, the relapse is more common, the disease progression is faster, and the survival time is shorter than those in the non-double-hit patients.

Effects of Bi incorporation on recombination processes in wurtzite GaBiAs nanowires.

The effects of Bi incorporation on the recombination process in wurtzite (WZ) GaBiAs nanowires are studied by employing micro-photoluminescence (µ-PL) and time-resolved PL spectroscopies. It is shown that at low temperatures (T < 75 K) Bi-induced localization effects cause trapping of excitons within band-tail states, which prolongs their lifetime and suppresses surface nonradiative recombination (SNR). With increasing temperature, the trapped excitons become delocalized and their lifetime rapidly shortens due to facilitated SNR. Furthermore, Bi incorporation in the GaBiAs NW is found to have a minor influence on the surface states responsible for SNR.

Effects of growth temperature and thermal annealing on optical quality of GaNAs nanowires emitting in the near-infrared spectral range.

We report on optimization of growth conditions of GaAs/GaNAs/GaAs core/shell/shell nanowire (NW) structures emitting at ∼1 µm, aiming to increase their light emitting efficiency. A slight change in growth temperature is found to critically affect optical quality of the active GaNAs shell and is shown to result from suppressed formation of non-radiative recombination (NRR) centers under the optimum growth temperature. By employing the optically detected magnetic resonance spectroscopy, we identify gallium vacancies and gallium interstitials as being among the dominant NRR defects. The radiative efficiency of the NWs can be further improved by post-growth annealing at 680 °C, which removes the gallium interstitials.

Measurements of Strain and Bandgap of Coherently Epitaxially Grown Wurtzite InAsP-InP Core-Shell Nanowires.

We report on experimental determination of the strain and bandgap of InAsP in epitaxially grown InAsP-InP core-shell nanowires. The core-shell nanowires are grown via metal-organic vapor phase epitaxy. The as-grown nanowires are characterized by transmission electron microscopy, X-ray diffraction, micro-photoluminescence (µPL) spectroscopy, and micro-Raman (µ-Raman) spectroscopy measurements. We observe that the core-shell nanowires are of wurtzite (WZ) crystal phase and are coherently strained with the core and the shell having the same number of atomic planes in each nanowire. We determine the predominantly uniaxial strains formed in the core-shell nanowires along the nanowire growth axis and demonstrate that the strains can be described using an analytical expression. The bandgap energies in the strained WZ InAsP core materials are extracted from the µPL measurements of individual core-shell nanowires. The coherently strained core-shell nanowires demonstrated in this work offer the potentials for use in constructing novel optoelectronic devices and for development of piezoelectric photovoltaic devices.

Molecular beam epitaxial growth of dilute nitride GaNAs and GaInNAs nanowires.

We report the growth of dilute nitride GaNAs and GaInNAs core-multishell nanowires (NWs) using molecular beam epitaxy assisted by a plasma source. Using the self-catalyst vapor-liquid-solid growth mode, these NWs were grown on Si(111) and silicon on insulator substrates. The GaNAs and GaInNAs shells contain nitrogen up to 3%. Axial cross-sectional scanning transmission electron microscopy measurements and energy-dispersive x-ray spectrometry confirm the formation of the core-multishell NW structure. We obtained high-quality GaNAs NWs with nitrogen compositions up to 2%. On the other hand, GaNAs containing 3% nitrogen, and GaInNAs NWs, show distorted structures; moreover, the optical emissions seem to be related to defects. Further optimisations of the growth conditions will improve these properties, promising future applications in nanoscale optoelectronics.

[Autologous peripheral blood stem cell transplantation for POEMS syndrome].

Six patients with POEMS syndrome who received autologous peripheral blood stem cell transplantation (auto-PBSCT) were retrospectively analyzed. Conditioning regimen was high dose melphalan. Peripheral blood stem cells were collected after mobilization with cyclophosphamide (CTX) and growth factors. One patient presenting hydrothorax and ascites was treated with 3 cycles of lenalidomide and dexamethasone before mobilization. Auto-PBSCT was fairly tolerable. Hematopoietic reconstitution was successful in all patients without transplantation-related mortality. A decrease or normalization of serum vascular epithelial growth factor (VEGF) was observed in all patients at 3 months after transplantation. The neurological remission was seen in 5/6 patients.

Second primary malignancies in multiple myeloma: an overview and IMWG consensus.

Background: Therapeutic advancements following the introduction of autologous stem cell transplantation and 'novel' agents have significantly improved clinical outcomes for patients with multiple myeloma (MM). Increased life expectancy, however, has led to renewed concerns about the long-term risk of second primary malignancies (SPMs). This review outlines the most up-to-date knowledge of possible host-, disease-, and treatment-related risk factors for the development of SPMs in patients with MM, and provides practical recommendations to assist physicians. Design: A Panel of International Myeloma Working Group members reviewed the most relevant data published in the literature as full papers, or presented at meetings of the American Society of Clinical Oncology, American Society of Hematology, European Hematology Association, or International Myeloma Workshops, up to June 2016. Here, we present the recommendations of the Panel, based on this literature review. Results: Overall, the risk of SPMs in MM is low, multifactorial, and partially related to the length of patients' survival and MM intrinsic susceptibility. Studies suggest a significantly increased incidence of SPMs when lenalidomide is administered either following, or concurrently with, oral melphalan. Increased SPM incidence has also been reported with lenalidomide maintenance following high-dose melphalan, albeit to a lesser degree. In both cases, the risk of death from MM was significantly higher than the risk of death from SPMs, with lenalidomide possibly providing a survival benefit. No increase in SPM incidence was reported with lenalidomide plus dexamethasone (without melphalan), or with bortezomib plus oral melphalan, dexamethasone, or thalidomide. Conclusion: In general, the risk of SPMs should not alter the current therapeutic decision-making process in MM. However, regimens such as lenalidomide plus dexamethasone should be preferred to prolonged exposure to lenalidomide plus oral melphalan. SPM risk should be carefully discussed with the patient in the context of benefits and risks of different treatment options.

Application of combined intraperitoneal and intravenous neoadjuvant chemotherapy in senile patients with advanced ovarian cancer and massive ascites.

OBJECTIVE: The aim of this study was to explore the effects of neoadjuvant chemotherapy in senile patients with advanced ovarian can- cer and ascites. MATERIALS AND METHODS: One hundred eight senile patients with advanced ovarian cancer and ascites were randomly di- vided into two groups: experimental and control groups. Patients in the experimental group were treated with two courses of intraperitoneal combined with intravenous neoadjuvant chemotherapy, followed by cytoreductive surgery, and six courses of intravenous chemotherapy, while the patients in the control group only received cytoreductive surgery and six to eight courses of intravenous chemotherapy. RESULTS: The operation duration, blood loss, ideal success rate of cytoreductive surgery, and prognosis of the two groups were then compared. Thirty-eight patients in the experimental group successfully received cytoreductive surgery, accounting for 74.14%, while only 23 patients in the control group received cytoreductive surgery successfully, accounting for 46%, showing signifinificantly less than those in the control group (p < 0.001). However, the median survival and the median progression-free survival showed no statistical difference between the two groups (p > 0.05). CONCLUSIONS: Neoadjuvant chemotherapy can obviously shorten the operation duration, reduce the intraoperative blood loss, and improve the ideal success rate of cytoreductive surgery, but does not obviously improve the prognosis.

[A prospective multi-center trial of non-interventional and observational study of lenalidomide in Chinese patients with multiple myeloma].

Objective: To evaluate the efficacy and safety of lenalidomide in a real-world clinical practice in Chinese patients with multiple myeloma (MM). Methods: It was a prospective, multi-center, observational study. A total of 165 consecutive patients with MM treated with lenalidomide-based regimens were enrolled in 12 hospitals from June 2013 to November 2015. Relevant information was recorded, such as baseline clinical data, cytogenetic abnormalities, treatment regimens, and duration of treatment, safety, and survival. Results: (1)There were 126 relapsed and refractory MM (RRMM) patients, 25 newly diagnosed patients and 19 maintenance patients. The evaluable RRMM patients accounted for 120 cases, among which 74 cases(61.7%) reached the partial response (PR) or above, and a very good partial response (VGPR) in 16 patients (13.3%), a complete response (CR) in 14 cases (11.7%), a strictly complete response (sCR) in 4 cases (3.3%). Thus, a VGPR or above in 34 patients accounted for 28.3%. (2)The median follow-up was 13 months, the median time to progression 12 months. The median survival after receiving lenalidomide was 19 months, and the median overall survival (OS) was 62 months. (3) The univariate analysis in 120 RRMM patients suggested that prognostic factors for significant improvement in PFS included normal karyotype, international staging system (ISS) Ⅰ-Ⅱ, t(4; 14) negative (detected by fluorescence in situ hybridization), non-bortezomib resistance and response to previous regimens. As to OS, non-bortezomib resistance, response to previous regimens and non-primary refractoriness were positive factors. Multivariate analysis showed that the response to previous regimens (PR or better) was an independent good prognostic factor for progress-free survival(PFS), non-bortezomib resistance and non-primary refractoriness for OS. (4) Grade 3 or 4 adverse events that occurred in more than 10% of all enrolled patients were neutropenia (12.7%), leukocytosis(11.5%) and thrombocytopenia (12.7%). Owing to intolerance of toxic side effects, 7 cases withdrew lenalidomide. Conclusions: No matter what combination, regimens containing lenalidomide are effective to RRMM patients with overall response rate 61.7%, a time to progression 12 months and an overall survival 62 months.The toxicity is quite tolerable and manageable. In addition, the response to previous treatment (reached PR or above) is the independent good prognostic factor for PFS, non-bortezomib resistance and non-primary refractoriness for OS. Clinical trail registration: Clinicaltrials.gov, NCT01947309.

[Effect and related mechanism of miRNA-21 on hydrogen peroxide-induced C-kit(+) cardiac stem cells apoptosis].

Objective: To explored the effect and related mechanism of miRNA-21 on hydrogen peroxide-induced C-kit(+) cardiac stem cells apoptosis. Methods: C-kit(+) cardiac stem cells were isolated from SD rats by the methods of enzyme digestion and magnetic bead. Cells were divided into the following experimental groups: (1) negative control mimics (NCM)group: cells were transfected with negative control miRNA-21 mimics for 48 hours; (2)mimics group: cells were transfected with miRNA-21 mimics for 48 hours; (3) NCM+ H(2)O(2) group: negative control miRNA-21 mimics were transfected into cells for 48 hours and then treated with 100 µmol H(2)O(2) for 2 hours; (4)mimics+ H(2)O(2) group: miRNA-21 mimics were transfected into cells for 48 hours and then treated with 100 µmol H(2)O(2) for 2 hours. mRNA of miRNA-21 was detected by RT-PCR. The apoptosis rate of C-kit(+) cardiac stem cells was determined using the annexin V-FITC/PI staining assay. Western blot was employed to measure the expression of apoptosis related proteins(Caspase-3, Bax, and Bcl-2). Results: (1) Compared with the NCM group, the mRNA expression level of miRNA-21 was significantly up-regulated in mimics group, while obviously down-regulated in NCM+ H(2)O(2) group(all P<0.05). Compared with the mimics group, the mRNA expression levels of miRNA-21 in mimics+ H(2)O(2) group was significantly downregulated (P<0.05), but remarkably upregulated compared with the NCM+ H(2)O(2) group(P<0.05). (2) Flow cytometry results indicated that the early apoptosis rates were similar between the NCM group and mimics group ((4.57±3.45)% vs. (5.13±3.21)%, P>0.05). Compared with the NCM group, the early apoptosis rates were remarkably increased ((79.07±5.75)% vs.(4.57±3.45)%, P<0.05) in NCM+ H(2)O(2) group. Compared with the mimics group, the early apoptosis was significantly up-regulated in the mimics+ H(2)O(2) group ((30.27±1.36)% vs.(5.13±3.21)%, P<0.05), which were further down-regulated in mimics+ H(2)O(2) group compared with the NCM+ H(2)O(2) group ((30.27±1.36)% vs.(79.07±5.75)%, P<0.05). (3) Western blot results showed similar protein expression of Caspase-3, Bax and Bcl-2 between NCM group and mimics group(all P>0.05). Compared with the NCM group, the Caspase-3 and Bax protein expression was significantly increased in NCM+ H(2)O(2) group (all P<0.05), but the protein expression level of Bcl-2 was similar between the 2 groups(P>0.05). The Caspase-3 and Bax protein expression was markedly decreased, while Bcl-2 apparently increased in the mimics+ H(2)O(2) group compared with the NCM+ H(2)O(2) group(all P<0.05). Conclusion: Overexpression of miRNA-21 protects the C-kit(+) cardiac stem cells from apoptosis caused by oxidative stress through downregulating proapoptotic and upregulating the antiapoptotic proteins.

[The effect and mechanism investigation of intermedin on the apoptosis of bone marrow derived mesenchymal stem cells induced by hydrogen peroxide].

Objective: To investigate the effect and mechanism of intermedin (IMD)on the apoptosis of BMSCs induced by H2O2 and its mechanism. Methods: BMSCs being cultured in vitro. After 30 min pretreatment with 10-6mol/L IMD, cells were cultured in presence of 100 µmol/L H2O2 for 2 hour, cell apoptosis was determined by flow cytometry; Apoptosis related protein expression was determined by Western blotting and immunofluorescence; Protein and phosphorylation of ERK1/2 was detected by Western blotting and observe the influence of IMD after pretreatment with inhibitor of ERK1/2. Results: IMD could increase phosphorylation of ERK1/2 pathway of BMSCs (P<0.01). Pretreatment of IMD could decrease BMSCs apoptosis induced by H2O2, and up regulation expression of Caspase-3 and Bax, down regulation expression of Bcl-2 (P<0.01), and the effect was abrogated by U0126. Conclusion: IMD can activate ERK1/2 signaling pathway of BMSCs, and can regulate the expression of apoptosis related proteins. Furthermore, it can protect BMSCs from apoptosis induced by H2O2. Activation of ERK1/2 pathway was involved in the effect of IMD on apoptosis.