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Abstract Background Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Methods Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Results Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg) for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4) hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Conclusion Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment.

MicroRNAs can act as tumour suppressors or oncogenes by regulating cellular differentiation, proliferation and apoptosis, and the dysregulation of miRNA is involved in the occurrence and development of NSCLC. Here, we provided evidence that miR‐92b as an oncogene in NSCLC by targeting PTEN/AKT. We found that miR‐92b was up‐regulated in human NSCLC tissues and cell lines. MiR‐92b knockdown suppressed the NSCLC cells proliferation and migration in both in vivo and in vitro models. Conversely, miR‐92b overexpression induced an aggressive phenotype. Moreover, miR‐92b‐mediated regulation of NSCLC cell proliferation and migration depended on binding to PTEN mRNA, which then led to the degradation of PTEN and activation of the downstream AKT signalling pathway. Overall, this study revealed the oncogenic roles of miR‐92b in NSCLC by targeting PTEN/AKT, and provided novel insights for future treatments of NSCLC patients. Significance of the study: MiR‐92b was up‐regulated in human NSCLC tissues and cell lines. Our study demonstrated that miR‐92b as an oncogene in NSCLC by targeting PTEN/AKT in both in vivo and in vitro models and provided novel insights for future treatments of NSCLC patients. [ABSTRACT FROM AUTHOR]

An in vivo study on enhancing epirubicin hydrochloride (EPI) inhibition on tumor growth by ultrasound (US) was reported. Five-week-old male nude mice were used and HL-60 cells were s.c. (subcutaneous injection) inoculated in axilla of these mice. Six groups were designed and five consecutive treatments were applied to investigate the inhibition on tumor growth and body weight growth. US applied locally to the tumor resulted in a substantially increased drug uptake in tumor cells. The inhibition on tumor growth depended on the position of drug injection and phospholipid-based microbubble (PMB) application. Tumor growth rate under group 1 (PMB+US) was similar to that of blank control. The order of the inhibition on tumor volume growth was: group 4 (s.c. EPI+PMB+US) > group 5 intraperitoneal (i.p. EPI+PMB+US) > group 2 (i.p. EPI) > group 3 (s.c. EPI+US) > group 1 (PMB+US). Similar conclusion was obtained from experimental measurements of tumor weight change. The order of animal survival status for EPI administration groups was: group 4 > group 5 > group 2 > group 3. Chemotherapeutic drug inhibition on tumor growth could be enhanced by local US combined with PMB, which might provide a potential application for US-mediated chemotherapy. [ABSTRACT FROM AUTHOR]

CDK2 forms a complex with cyclin A and cyclin E to promote the progress of cell cycle, but when cyclin A and cyclin E are dissociated from the complex and degraded by the ubiquitin proteasome pathway, the fate of the inactive CDK2 is unclear. In this study, we found that the inactive CDK2 protein was degraded by autophagy-lysosome pathway. In the classic model of G0/G1 phase arrest induced by serum starvation, we found that the mRNA level in CDK2 did not change but the protein level decreased. Subsequently, using PI3K and AKT inhibitors and gene knockout methods, it was found that CDK2 degradation was mediated by the inhibition of PI3Kα/AKTT308. In addition, P62/SQSTM1 was found to bind to the inactivated CDK2 protein to help it enter autophagy-lysosome degradation in a CTSB-dependent manner. Taken together, these results confirm that the PI3Kα/AKTT308 inhibition leads to degradation of CDK2 protein in the autophagy-lysosome pathway. These data reveal a new molecular mechanism of CDK2 protein degradation and provide a new strategy and method for regulating CDK2 protein. • Autophagy-lysosome pathway is involved in serum starvation-induced degradation of CDK2 protein. • The downregulation of CDK2 protein is mediated by the inhibition of PI3Kα/AKTT308. • P62/SQSTM1 mediates the autophagic degradation of CDK2 protein. [ABSTRACT FROM AUTHOR]

Background: CDK4 is highly expressed and associated with poor prognosis and decreased survival in advanced neuroblastoma (NB). Targeting CDK4 degradation presents a potentially promising therapeutic strategy compared to conventional CDK4 inhibitors. However, the autophagic degradation of the CDK4 protein and its anti-proliferation effect in NB cells has not been mentioned., Results: We identified autophagy as a new pathway for the degradation of CDK4. Firstly, autophagic degradation of CDK4 is critical for NVP-BEZ235-induced G0/G1 arrest, as demonstrated by the overexpression of CDK4, autophagy inhibition, and blockade of autophagy-related genes. Secondly, we present the first evidence that p62 binds to CDK4 and then enters the autophagy-lysosome to degrade CDK4 in a CTSB-dependent manner in NVP-BEZ235 treated NB cells. Similar results regarding the interaction between p62 and CDK4 were observed in the NVP-BEZ235 treated NB xenograft mouse model., Conclusions: Autophagic degradation of CDK4 plays a pivotal role in G0/G1 cell cycle arrest in NB cells treated with NVP-BEZ235.

Hematopoietic cells are regulated by many transcriptional factors during their development, among them the Ikaros family is one of the most important representatives. They have characteristic conserved structural motifs, binding with DNA specific short sequences-containing key gene promoter or enhancer, to regulate their transcription activity. Meanwhile, the Ikaros family interact with other related transcriptional regulators to regulate the development and differentiation of hematopoietic cells. The structure of the Ikaros family, which belong to the zinc finger transcription factor, including Ikaros, Helios, Aiolos, Eos and Pegasus, are encoded by IKZF1-5 genes, respectively. They are master regulators of hematopoiesis, playing important roles in the occurrence, development and function of hematopoietic cells such as lymphocytes via individual and joint regulation. When working abnormalities, they are often related with the occurrence and development of the disease. In this review, the research achievements of the Ikaros family in recent years are summarized. On the one hand, it is helpful to understand the role and significance of this family in hematopoietic system; on the other hand, it provides the possible research direction for further research work.

The distinction between chromophobe renal cell carcinoma (ChRCC), clear cell renal cell carcinoma (CRCC) and renal oncocytoma may cause a diagnostic dilemma. The usefulness of DOG1, cyclin D1, CK7, CD117 and vimentin in the differential diagnosis of these renal epithelial tumors was investigated. DOG1 was positive in ChRCC (32 of 32, 100%) and in renal oncocytoma (21 of 21, 100%). In contrast, DOG1 was absent in all CRCC (0 of 30). Cyclin D1 was positive in renal oncocytomas (17 of 21, 81%) but negative in the ChRCC (0/23) and CRCC (0 of 30). CK7 was positive in ChRCC (30 of 32, 94%), but was negative in oncocytoma (only scattered single positive cells), and was only focal positive in two cases of CRCC. CD117 was expressed in 88% of ChRCC (28 of 32), 86% of renal oncocytoma (18 of 21), and was negative in all CRCC (0 of 30). Twenty-six of the 30 cases of CRCC were positive (87%) for vimentin with prominent membrane staining patterns. All 23 chromophobe carcinomas were negative for vimentin and 15 of 21 oncocytomas demonstrated focal vimentin positivity, but less than 10%. The above results demonstrate that: (1) DOG1 was very sensitive and specific marker for distinguish ChRCC from CRCC; (2) Cyclin D1 was a useful marker to discriminate between ChRCC and renal oncocytoma; (3) CK7 and CD117 were useful markers to distinguish ChRCC from renal oncocytoma and CRCC. (4) Vimentin was helpful for distinguishing clear cell RCC from chromophobe and oncocytoma (87% of clear cell RCC positive, negative in chromophobe, only focally positive in oncocytoma). (5) CK8/18, CK19, CD10, β-catenin and E-cadherin could not be used to distinguish ChRCC from renal oncocytoma and CRCC., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Objective: To investigate the relationship between EGFR activation and down-regulation of miRNA-145 in lung cancer., Methods: Normal human lung epithelia cell line (BEAS-2B), human lung adenocarcinoma cell lines with wild-type EGFR (A549 and H292) and human lung adenocarcinoma cell lines with EGFR mutation (H1975 and H1650) were chosen in this study. The levels of miRNA-145 and p-EGFR were determined by quantitative real-time PCR (qRT-PCR) and Western blotting, respectively, and the relationship between p-EGFR and miRNA-145 levels was analyzed. The miRNA-145 levels were determined by qRT-PCR after activating EGFR with EGF or blocking EGFR signal pathway with AG1478. In addition, ERK1/2 inhibitor U0126 was used to inhibit ERK1/2 activation and then the expression of miRNA-145 was detected., Results: The miRNA-145 levels were closely negatively related with p-EGFR in lung cancer cells (r = -0.926, P = 0.024). EGF down-regulated miRNA-145 expression, particularly in BEAS-2B cells (53.0%; t = 30.993, P = 0.001) and A549 cells (42.6%; t = 14.326, P = 0.005).The miRNA-145 was up-regulated after inhibiting p-EGFR with AG1478, and significantly enhanced by 67.5% in H1975 cells when treated with AG1478 (t = 8.269, P = 0.014). The ERK1/2 signal pathway was activated by p-EGFR. U0126 restored the miRNA-145 down-regulation induced by EGFR-activation in lung cancer cells., Conclusion: The activation of EGFR down-regulates miRNA-145 expression through ERK1/2 in lung cancer cells.

Objective: To investigate the relationship between janus kinase2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway and angiogenesis in non-small cell lung cancer (NSCLC) and explore the effects on the mRNA expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) by blocking JAK2/STAT3 signaling pathway., Methods: Immunohistochemistry was used to determine the expression of P-JAK2, P-STAT3 and microvessel density (MVD) in 68 NSCLC tissues and 27 normal lung tissues. And the relationship with their clinical pathological features was analyzed. Human lung cancer A549 cells were treated with different concentrations of AG490. Cell proliferation was measured by MTT assay. Western blot was performed to detect the activation of JAK2/STAT3 signaling pathway. The mRNA expressions of VEGF and bFGF were determined by RT-PCR (reverse transcription-polymerase chain reaction). A549 cells were transfected with STAT3 siRNA. And the protein of STAT3, Phos-STAT3 (P-STAT3) and mRNA levels of VEGF and bFGF were detected., Results: The activation of JAK2/STAT3 signaling pathway was closely related to MVD in NSCLC. AG490 and STAT3 siRNA could block the JAK2/STAT3 signaling pathway and down-regulated the mRNA expressions of VEGF and bFGF in lung cancer cells., Conclusion: JAK2/STAT3 signaling pathway plays an important role in the angiogenesis of NSCLC. Blocking this pathway may inhibit the expression of angiogenic cytokines. JAK2/STAT3 signaling pathway may be a critical therapeutic target for the treatment of angiogenesis in NSCLC.