Sulforaphane-N-Acetyl-Cysteine Induces Autophagy Through Activation of ERK1/2 in U87MG and U373MG Cells

Background/Aims: Sulforaphane-N-acetyl-cysteine (SFN-NAC) is a sulforaphane (SFN) metabolite with a longer half-life and better blood–brain barrier permeability than those of SFN. Previous studies have found that SFN-NAC can act via ERK to destroy microtubules and inhibit cell growth in lung cancer cells. However, the underlying mechanisms are unclear, and it is unknown whether SFN-NAC can inhibit the growth of glioma. Here, we have demonstrated for the first time that SFN-NAC activates autophagy-mediated downregulation of α-tubulin expression via the ERK pathway. Methods: U87MG and U373MG cells, two widely used glioma cell lines, were utilized in this study. Apoptosis assay, western blot analysis, co-immunoprecipitation, immunostaining, and electron microscopy were used to analyze the effect of SFN-NAC on α-tubulin and its interaction with microtube-associated protein 1 light-chain 3 (LC3). Results: SFN-NAC induced cell-cycle arrest in the G2/M phase and dose-dependently induced intracellular ERK activation, autophagy, and α-tubulin downregulation. These SFN-NAC-induced effects were reversed by inhibiting the ERK pathway with its inhibitor PD98059. U87MG and U373MG cells were transfected with LC3 small interfering RNA, and the subsequent inhibition of autophagy reversed the downregulation of α-tubulin by SFN-NAC. Furthermore, co-immunoprecipitation experiments and confocal microscopy confirmed that SFN-NAC promotes the binding of LC3 with α-tubulin in the cytoplasm. Cell viability experiments demonstrate that SFN-NAC inhibits the growth of U87MG and U373MG cell colonies. Conclusion: These findings suggest that SFN-NAC is a novel potential anti-glioma agent

A new score system for predicting response to cardiac resynchronization therapy

Background: The aim of this study was to establish a score system derived from clinical, echocardiographic and electrocardiographic indexes and evaluate its clinical value for cardiac resynchronization therapy (CRT) patient selection. Methods: Ninety-three patients receiving CRT were enrolled. A patient selection score system was generated by the clinical, echocardiographic and electrocardiographic parameters achieving a significant level by univariate and multivariate Cox regression model. The positive response to CRT was a left ventricular end systolic volume decrease of ≥ 15% and not reaching primary clinical endpoint (death or re-hospitalization for heart failure) at the end of follow-up. Results: Thirty-nine patients were CRT non-responders (41.94%) and 54 were responders (58.06%). A 4-point score system was generated based on tricuspid annular plane systolic ex­cursion (TAPSE), longitudinal strain (LS), and complete left bundle branch block (CLBBB) combined with a wide QRS duration (QRSd). The sensitivity and specificity for prediction of a positive response to CRT at a score > 2 were 0.823 and 0.850, respectively (AUC: 0.92295% CI 0.691–0.916, p< 0.001). Conclusions: A patient selection score system based on the integration of TAPSE, LS and CLBBB combined with a wide QRSd can help to predict positive response to CRT effectively and reliably

Skp2 expression unfavorably impacts survival in resectable esophageal squamous cell carcinoma

<p>Abstract</p> <p>Background</p> <p>The correlation of S-phase kinase–associated protein 2 (Skp2) with metastasis and prognosis in esophageal squamous cell carcinoma (ESCC) is controversial. The purpose of this study was to explore whether there was a correlation between the expression of Skp2 evaluated by immunohistochemistry and the clinical outcome of patients with operable ESCC, and to further determine the possible mechanism of the impact of Skp2 on survival.</p> <p>Methods</p> <p>Tissue microarrays that included 157 surgically resected ESCC specimens was successfully generated for immunohistochemical evaluation. The clinical/prognostic significance of Skp2 expression was analyzed. Kaplan-Meier analysis was used to compare the postoperative survival between groups. The prognostic impact of clinicopathologic variables and Skp2 expression was evaluated using a Cox proportional hazards model. A cell proliferation assay and a colony formation assay were performed in ESCC cell lines to determine the function of Skp2 on the progression of ESCC <it>in vitro</it>.</p> <p>Results</p> <p>Skp2 expression correlated closely with the T category (<it>p</it> = 0.035) and the pathological tumor-node-metastasis (TNM) stage (<it>p</it> = 0.027). High expression of Skp2 was associated with poor overall survival in resectable ESCC (<it>p</it> = 0.01). The multivariate Cox regression analysis demonstrated that pathological T category, pathological N category, cell differentiation, and negative Skp2 expression were independent factors for better overall survival. <it>In vitro</it> assays of ESCC cell lines demonstrated that Skp2 promoted the proliferative and colony-forming capacity of ESCCs.</p> <p>Conclusions</p> <p>Negative Skp2 expression in primary resected ESCC is an independent factor for better survival. Skp2 may play a pro-proliferative role in ESCC cells.</p

Characterization of starch structures isolated from the grains of waxy, sweet, and hybrid sorghum (Sorghum bicolor L. Moench)

In this study, starches were isolated from inbred (sweet and waxy) and hybrid (sweet and waxy) sorghum grains. Structural and property differences between (inbred and hybrid) sweet and waxy sorghum starches were evaluated and discussed. The intermediate fraction and amylose content present in hybrid sweet starch were lower than those in inbred sweet starch, while the opposite trend occurred with waxy starch. Furthermore, there was a higher A chain (30.93–35.73% waxy, 13.73–31.81% sweet) and lower B2 + B3 chain (18.04–16.56% waxy, 24.07–17.43% sweet) of amylopectin in hybrid sorghum starch. X-ray diffraction (XRD) and Fourier transform infrared reflection measurements affirm the relative crystalline and ordered structures of both varieties as follows: inbred waxy &gt; hybrid waxy &gt; hybrid sweet &gt; inbred sweet. Small angle X-ray scattering and 13C CP/MAS nuclear magnetic resonance proved that the amylopectin content of waxy starch was positively correlated with lamellar ordering. In contrast, an opposite trend was observed in sweet sorghum starch due to its long B2 + B3 chain content. Furthermore, the relationship between starch granule structure and function was also concluded. These findings could provide a basic theory for the accurate application of existing sorghum varieties precisely

CAMKs support development of acute myeloid leukemia.

BACKGROUND: We recently identified the human leukocyte immunoglobulin-like receptor B2 (LILRB2) and its mouse ortholog-paired Ig-like receptor (PirB) as receptors for several angiopoietin-like proteins (Angptls). We also demonstrated that PirB is important for the development of acute myeloid leukemia (AML), but exactly how an inhibitory receptor such as PirB can support cancer development is intriguing. RESULTS: Here, we showed that the activation of Ca (2+)/calmodulin-dependent protein kinases (CAMKs) is coupled with PirB signaling in AML cells. High expression of CAMKs is associated with a poor overall survival probability in patients with AML. Knockdown of CAMKI or CAMKIV decreased human acute leukemia development in vitro and in vivo. Mouse AML cells that are defective in PirB signaling had decreased activation of CAMKs, and the forced expression of CAMK partially rescued the PirB-defective phenotype in the MLL-AF9 AML mouse model. The inhibition of CAMK kinase activity or deletion of CAMKIV significantly slowed AML development and decreased the AML stem cell activity. We also found that CAMKIV acts through the phosphorylation of one of its well-known target (CREB) in AML cells. CONCLUSION: CAMKs are essential for the growth of human and mouse AML. The inhibition of CAMK signaling may become an effective strategy for treating leukemia

Effect of Low Power Laser Irradiation on the Ability of Cell Growth and Myogenic Differentiation of Myoblasts Cultured In Vitro

As a therapeutic modality, low power laser irradiation (LPLI) has been used clinically in the treatment of skeletal muscle injuries and other myopathic conditions, but the cellular and molecular mechanisms attributed to this therapy were still unclear. Myoblasts are a type of myogenic stem cells quiescence in mature skeletal muscle fibers and are considered as the source cells during the regenerating process. The purpose of this paper was to investigate the effects of LPLI on the proliferation and myogenic differentiation of the cultured myoblasts and to find out the major candidates responsible for LPLI-induced muscle regeneration in vivo. In this study, primary rat myoblasts were exposed to helium-neon (He-Ne) laser. Cell proliferation, differentiation, and the cellular responses to LPLI were monitored by using morphological observation and molecular biological methods. It was found that LPLI at a certain fluence could increase the cell growth potential for myoblasts and further induce more cells entering into S phase of the mitotic cycle as indicated by high levels of bromodeoxyuridine (BrdU) incorporation, while at the same time inhibiting their in vitro differentiation and decreasing the expression of myogenic regulatory genes to a certain extent. Taken together, these results provide experimental evidence for the clinical applications of LPLI in regenerating skeletal muscle

Stimulative Effects of Low Intensity He-Ne Laser Irradiation on the Proliferative Potential and Cell-Cycle Progression of Myoblasts in Culture

Low intensity laser irradiation (LILI) was found to promote the regeneration of skeletal muscle in vivo but the cellular mechanisms are not fully understood. Myoblasts, normally quiescent and inactivated in adult skeletal muscle, are a type of myogenic progenitor cells and considered as the major candidates responsible for muscle regeneration. The aim of the present study was to study the effect of LILI on the growth potential and cell-cycle progression of the cultured myoblasts. Primary myoblasts isolated from rat hind legs were cultured in nutrient-deficient medium for 36 hours and then irradiated by helium-neon laser at a certain energy density. Immunohistochemical and flow cytometric analysis revealed that laser irradiation could increase the expression of cellular proliferation marker and the amount of cell subpopulations in the proliferative phase as compared with the nonirradiated control group. Meanwhile, the expressions of cell-cycle regulatory proteins in the laser-treated myoblasts were markedly upregulated as compared to the unirradiated cells, indicating that LILI could promote the reentry of quiescent myoblasts into the cell division cycle. These results suggest that LILI at certain fluences could promote their proliferation, thus contributing to the skeletal muscle regeneration following trauma and myopathic diseases