STEAP4 inhibits cisplatin-induced chemotherapy resistance through suppressing PI3K/AKT in hepatocellular carcinoma.

Chemotherapy resistance is the leading cause for hepatocellular carcinoma (HCC)-induced death. Exploring resistance generation mechanism is an urgent need for HCC therapy. Here, we found STEAP4 was significantly downregulated in HCC patients with recurrence. Patients with low STEAP4 had poor outcome, suggesting STEAP4 might inhibit chemotherapy resistance. Cell viability assay, colony formation assay, apoptosis assay, soft agar growth assay, and tumor animal model showed STEAP4 inhibited cisplatin resistance. Mechanism analysis showed STEAP4 inhibited PI3K/AKT pathway through directly interacting with AKT. Double knockdown of STEP4 and AKT significantly inhibited cisplatin resistance. We also found STEAP4 expression was negatively correlated with PI3K/AKT pathway activity in clinic specimens. In summary, our findings suggested STEAP4 inhibited cisplatin resistance through suppressing PI3K/AKT pathway activity, providing a target for HCC therapy.

Differences and spatial variations of plant leaf calorific value in deserts of the Hexi Corridor, Northwestern China.

The leaf calorific value (LCV) is an important trait that indicates how efficiently a plant utilizes natural resources to capture energy. However, little is known about the LCV characteristics of plants in arid and hyper-arid environments. To investigate the spatial patterns and variations in LCV of desert plants and their possible causes, we collected 343 leaf samples of 52 species along a 1000-km transect in the desert area of northwestern China. We analyzed the gross calorific value (GCV), ash-free calorific value (AFCV), carbon content (CC), nitrogen content (NC), and ash content (AC) of the leaves. The mean leaf GCV and AC were 16.2 kJ g-1 (range from 8.9 to 20.1 kJ g-1), and 189.8 mg g-1 (range from 61.5 to 495.1 mg g-1) respectively, which differ significantly from the values for plants growing in more humid areas of China. Succulence was the dominant trait that drove the differences in leaf GCV and AFCV among plant functional groups. Succulent plants had significantly lower leaf GCV and AFCV, and significantly higher AC, than non-succulent plants, indicating that the investment of energy for succulent plants in response to drought stress may be lower than that for non-succulent plants. Among the biological factors that affected LCV, the CC and AC were the main determinants of leaf GCV, whereas CC and NC were the main determinants of leaf AFCV. Drought stress is an environmental constraint that has a direct negative effect on both leaf GCV and AFCV, but its contribution may be weaker than phylogenetic effects. Our results suggest that LCV is a useful leaf trait that can be used to evaluate plant-environment interactions from an energy perspective.

Application of ultrasound-guided biopsy and percutaneous radiofrequency ablation in 2 cases with phosphaturic mesenchymal tumor and literature review.

Tumor-induced osteomalacia (TIO) is a vanishingly rare paraneoplastic syndrome which is usually caused by phosphaturic mesenchymal tumors (PMTs). The conventional treatment for PMTs is total resection, and ultrasound-guided radiofrequency ablation (RFA) can also be used for the treatment of PMTs patients, especially for patients in whom complete resection may lead to serious complications. We report two cases with PMT who presented syndrome with progressive musculoskeletal complaints and performed ultrasound-guided biopsy and RFA. Ultrasound-guided RFA, which is a safe and effective minimally invasive treatment option, appears to be a valuable alternative to surgery for patients presenting with PMT. We are the first reported case of RFA guided by ultrasonography in the treatment of PMT.

MYB Proto-oncogene-like 1-TWIST1 Axis Promotes Growth and Metastasis of Hepatocellular Carcinoma Cells.

MYB proto-oncogene-like 1 (MYBL1) has been reported to be a strong activator of transcription and plays an important role in the development of cancer. However, the precise biological function and molecular mechanism of MYBL1 in hepatocellular carcinoma (HCC) cells remain unclear. In the present study, we found that the expression of MYBL1 was markedly overexpressed in HCC cell lines and HCC samples, respectively. Moreover, MYBL1 expression positively correlated with tumor progression and inversely correlated with patient survival in 368 human HCC tissue samples. Overexpression of MYBL1 induced, whereas knockdown of MYBL1 reduced, HCC proliferation and metastasis both in vitro and in vivo. Furthermore, we demonstrated that HCC patients with high MYBL1 expression had significantly shorter overall and poorer disease-free survival than those with low MYBL1 expression. MYBL1 transcriptionally upregulated TWIST1 expression by directly targeting the TWIST1 promoter. More importantly, the in vitro analysis was consistent with the significant correlation between MYBL1 and TWIST1 expression observed in a large cohort of human HCC specimens. Taken together, our results demonstrate that MYBL1 plays an important role in HCC growth and metastasis and reveal a plausible mechanism for upregulation of TWIST1 in HCC.

CircRNA has_circ_0078710 acts as the sponge of microRNA-31 involved in hepatocellular carcinoma progression.

Circular RNAs (circRNAs) as new types of endogenous non-coding RNAs have been recently identified important roles in certain types of pathological responses, and in the occurrence and progression of a variety of human malignancies. In the present study, we aimed to evaluate the role of has_circ_0078710, which is back spliced by THBS2 gene in hepatocellular carcinoma (HCC). Expression levels of has_circ_0078710 were tested in both HCC tissue samples and cells using real-time qRT-PCR. Has_circ_0078710 was significantly unregulated in HCC tissues and cells. Moreover, HCC patients with high level of has_circ_0078710 had the advance stage (TNM III-IV). Finally, we constructed an interaction network among circRNA-miRNA-mRNA and we identified miR-31 as the has_circ_0078710-associatedmiRNA. Furthermore, overexpression of has_circ_0078710 in HCC could up-regulate HDAC and CDK2 levels by sponging miR-31, simultaneously mediating the expression of cell cycle components (cyclin A, cyclin D1, CDK4) and negative cell cycle regulator p21. In vitro and in vivo functional studies showed that overexpression of has_circ_0078710 in HepG2, SMMC-7721 cell lines significantly promoted cell proliferation, migration, invasion and tumor growth by inducing the cell cycle progression. In summary, we identified Has_circ_0078710 as a potential HCC biomarker.

MicroRNA-1271 functions as a potential tumor suppressor in hepatitis B virus-associated hepatocellular carcinoma through the AMPK signaling pathway by binding to CCNA1.

Hepatocellular carcinoma (HCC) is mainly associated with hepatitis B virus (HBV) infection and characterized by metastasizing and infiltrating adjacent and distant tissues. Notably, microRNA-1271 (miR-1271) is a tumor suppressor in various cancers. Therefore, we evaluate the ability of miR-1271 to influence cell proliferation, migration, invasion, and apoptosis in HBV-associated HCC through the Adenosine monophosphate-activated protein kinase (AMPK) signaling pathway via targeting CCNA1. HBV-associated HCC and adjacent normal tissues were collected to identify the expression of miR-1271 and CCNA1. To verify the relationship between miR-1271 and CCNA1, we used bioinformatics prediction and the dual-luciferase reporter gene assay. The effects of miR-1271 on HBV-associated HCC cell behaviors were investigated by treatment of the miR-1271 mimic, the miR-1271 inhibitor, or small interfering RNA against CCNA1. The HBV-DNA quantitative assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromid assay, scratch test, transwell assay, and flow cytometry were used to detect HBV-DNA replication, cell proliferation, invasion, migration, and apoptosis. MiR-1271 showed a low expression, whereas CCNA1 showed a high expression in HBV-associated HCC tissues. We identified that miR-1271 targeted and negatively regulated CCNA1. Upregulated miR-1271 and downregulated CCNA1 inhibited the HBV-associated HCC cell HBV-DNA replication, proliferation, migration, and invasion, while accelerating apoptosis by activating the AMPK signaling pathway. MiR-1271 promotes the activation of the AMPK signaling pathway by binding to CCNA1, whereby miR-1271 suppresses HBV-associated HCC progression. This study points to a potential therapeutic approach of downregulation of miR-1271 in HBV-associated HCC treatment.

LncRNA FLVCR1-AS1 acts as miR-513c sponge to modulate cancer cell proliferation, migration, and invasion in hepatocellular carcinoma.

In the present study, we aimed to search for dysregulated lnRNAs in Hepatocellular carcinoma (HCC) tissues, and analyze the relationship of its expression level with the clinicopathological feature and patient prognosis. The biological function of FLVCR1-AS1, the identified lncRNA, in the process of HCC development, and progression was investigated in vitro and in vivo. The underlying molecular mechanism was further explored. We determined FLVCR1-AS1 expression in HCC tissues and peri-tumor tissues by bioinformatic analysis, qRT-PCR, Northern blot and in situ hybridization. The relationship between FLVCR1-AS1 expression level and prognosis was determined by analyzing clinical samples. The effects of FLVCR1-AS1 knockdown on HCC cell proliferation, apoptosis, migration, and invasion were investigated by CCK8, FACS, and tanswell assay, respectively. Tumor xenograft model was used to determine the influence of down-regulated FLVCR1-AS1 on tumor growth and metastasis. lncRNA FLVCR1-AS1 was extremely up-regulated in HCC tissues and cell lines. FLVCR1-AS1 expression level was positively correlated with tumor severity. FLVCR1-AS1 knockdown remarkably inhibited HCC cell proliferation, migration, and invasion in vitro and in vivo while induced cell apoptosis. In mechanism, FLVCR1-AS1 acted as a competitive endogenous RNAs to sponge miR-513c which targeted the mRNA of MET for degradation. By directly sponging miR-513c, FLVCR1-AS1 increased MET expression in HCC, and then promoted HCC progression. It was demonstrated that FLVCR1-AS1 played a positive role in HCC development and progression according to the study in its mechanism, function and clinical manifestation, so that it could be expected to become a new target in HCC prevention and treatment.

IL-25 stimulates M2 macrophage polarization and thereby promotes mitochondrial respiratory capacity and lipolysis in adipose tissues against obesity.

Obesity and associated metabolic diseases are characterized by a chronic low-grade inflammatory state with the infiltration of many inflammatory cells, especially macrophages. Immune molecules, including some cytokines, have a close relationship with metabolism. Interleukin (IL)-25 is a member of the IL-17 cytokine family that can regulate macrophages and alleviate some metabolic dysfunction; however, its role and mechanisms in lipid metabolism remain to be extensively clarified. Human serum and liver biopsy specimens, high-fat diet-induced obesity mice and DB/DB (Lepr-/-) animal models were used to examine IL-25 expression in obesity and nonalcoholic fatty liver diseases (NAFLD). To observe the role of IL-25 in lipid metabolism, model mice were administered with IL-25 or adoptively transferred with IL-25-educated macrophages in vivo, whereas bone marrow-derived macrophages, the macrophage cell line RAW264.7 and adipocytes differentiated from 3T3-L1 were used in vitro. IL-25 was decreased in NAFLD patients and obese mice. In addition, IL-25 reduced body weight gain and lipid accumulation, enhanced lipid uptake by macrophages and increased the expression of lipolysis and ß-oxidation enzymes via alternatively activating macrophages. IL-25 also promoted lipolysis and suppressed lipogenesis in adipocytes co-cultured with the IL-25-educated macrophages. Furthermore, IL-25 improved the mitochondrial respiratory capacity and oxygen consumption rate of macrophages and produced more NAD+/NADH and ATP. In conclusion, IL-25 can stimulate M2 macrophage polarization and thereby promote lipolysis and mitochondrial respiratory capacity, highlighting the potential for IL-25 to be used as a therapeutic agent against obesity and associated metabolic syndromes.

Long noncoding RNA lnc-sox5 modulates CRC tumorigenesis by unbalancing tumor microenvironment.

Long non-coding RNAs (LncRNAs) have been recently regarded as systemic regulators in multiple biologic processes including tumorigenesis. In this study, we observed the expression of lncRNA lnc-sox5 was significantly increased in colorectal cancer (CRC). Despite the CRC cell growth, cell cycle and cell apoptosis was not affected by lnc-sox5 knock-down, lnc-sox5 knock-down suppressed CRC cell migration and invasion. In addition, xenograft animal model suggested that lnc-sox5 knock-down significantly suppressed the CRC tumorigenesis. Our results also showed that the expression of indoleamine 2,3-dioxygenase 1 (IDO1) was significantly reduced by lnc-sox5 knock-down and therefore modulated the infiltration and cytotoxicity of CD3+CD8+T cells. Taken together, these results suggested that lnc-sox5 unbalances tumor microenvironment to regulate colorectal cancer progression.

Deregulation of miR-193b affects the growth of colon cancer cells via transforming growth factor-ß and regulation of the SMAD3 pathway.

MicroRNA-193b (miRNA-193b) is often differentially expressed and is an important regulator of gene expression in colon cancer. The aim of the present study was to determine whether miRNA-193b affects cell growth in colon cancer and to investigate the potential underlying mechanisms. Patients with colorectal cancer (CRC; n=20) and healthy volunteers (n=10) were enrolled from the Department of Gastrointestinal Surgery Center, First Affiliated Hospital of Sun Yat-Sen University (Guangzhou, China). Western blot analysis was used to evaluate the protein expression of SMAD3 and transforming growth factor-ß (TGF-ß) in the patient samples. It was determined that miRNA-193b expression was markedly elevated in the CRC tissue samples. Furthermore, silencing of miRNA-193bin SW620 CRC cells by specific inhibitors significantly reduced the cell proliferation and induced apoptosis. In addition, the downregulation of miRNA-193b significantly activated the protein expression of SMAD3 and TGF-ß, and promoted caspase-3 activity in SW620 cells. The results of the present study suggested that the deregulation of miRNA-193b may affect cell growth in colon cancer via the TGF-ß and SMAD3 signaling pathways.

Special AT-rich sequence binding protein 1 promotes tumor growth and metastasis of esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma is one of the most aggressive malignancies worldwide. Special AT-rich sequence binding protein 1 is a nuclear matrix attachment region binding protein which participates in higher order chromatin organization and tissue-specific gene expression. However, the role of special AT-rich sequence binding protein 1 in esophageal squamous cell carcinoma remains unknown. In this study, western blot and quantitative real-time polymerase chain reaction analysis were performed to identify differentially expressed special AT-rich sequence binding protein 1 in a series of esophageal squamous cell carcinoma tissue samples. The effects of special AT-rich sequence binding protein 1 silencing by two short-hairpin RNAs on cell proliferation, migration, and invasion were assessed by the CCK-8 assay and transwell assays in esophageal squamous cell carcinoma in vitro. Special AT-rich sequence binding protein 1 was significantly upregulated in esophageal squamous cell carcinoma tissue samples and cell lines. Silencing of special AT-rich sequence binding protein 1 inhibited the proliferation of KYSE450 and EC9706 cells which have a relatively high level of special AT-rich sequence binding protein 1, and the ability of migration and invasion of KYSE450 and EC9706 cells was distinctly suppressed. Special AT-rich sequence binding protein 1 could be a potential target for the treatment of esophageal squamous cell carcinoma and inhibition of special AT-rich sequence binding protein 1 may provide a new strategy for the prevention of esophageal squamous cell carcinoma invasion and metastasis.

Roles of mitochondrial transcription factor A and microRNA­590­3p in the development of colon cancer.

Mitochondrial transcription factor A (TFAM) participates in the process of mitochondrial DNA replication and transcription. microRNAs (miRNAs) serve an important role in the regulation of gene expression. However, the roles of TFAM and certain miRNAs and their associations in the development of numerous cancer types remain unclear. The current study demonstrated that the expression of TFAM was significantly upregulated in colon cancer compared with the normal tissue, while the expression of miRNA­590­3p (miR­590­3p) was predicted with a high score using miRWalk software, and the luciferase assay demonstrated that TFAM was the direct target of miRNA­590­3p. miR­590­3p exhibited high expression levels in both colon cancer tissue and the SW480 cell line. Furthermore, downregulated expression of miR­590­3p significantly inhibited the growth of SW480 cells, which was consistent with results indicating downregulated expression of TFAM in SW480 cells from a previous study. In summary, the results of the current study concluded that miR­590­3p, via direct targeting of TFAM, may serve an important role in the tumorigenesis of colon cancer, and may be a promising target for colon cancer therapeutics.

Long non-coding RNA TUG1 promotes colorectal cancer metastasis via EMT pathway.

Colorectal cancer (CRC) is the third most common malignancy in developed countries, and its incidence rate has been continuously increasing in developing countries over the past few decades. Taurine-upregulated gene 1 (TUG1) plays an important role in signal transduction, regulation of cell morphology, migration, proliferation and apoptosis. The aim of the present study was to evaluate the role of TUG1 in CRC, and whether knockdown of TUG1 expression could affect cell proliferation, migration and invasion of CRC cell lines. Here, we reported that TUG1 was upregulated in CRC. Further experiments revealed that TUG1 knockdown significantly inhibited cell proliferation, migration and invasion of CRC in vitro. Above all, knockdown of TUG1 may represent a rational therapeutic strategy for CRC patients in future.

MCL-1 is the key target of adjuvant chemotherapy to reverse the cisplatin-resistance in NSCLC.

Cisplatin is one of the most effective chemotherapeutic agents for the treatment of lung cancer. However, the acquired resistance occurred in cancer cells limits the clinical application of cisplatin. MCL-1, which is an important member in the pro-survival Bcl-2 family, plays a critical role in multidrug resistance (MDR). The aim of the present study is to investigate the value of Pan-Bcl-2 inhibitor as sensitizer for the chemotherapy of cisplatin-resistant non-small cell lung cancer (NSCLC) cells. We found the obatoclax but not the ABT-737 significantly decreased the IC50 (half maximal inhibitory concentration) of cisplatin in cisplatin-resistant NSCLC cells. Furthermore, we demonstrated that the mechanism of obatoclax-promoted cell death induced by cisplatin was dependent on the inhibition of MCL-1, which couldn't be inhibited by ABT-737 but is the target of obatoclax. Moreover, inhibition of MCL-1 recovered the function of NOXA and BAK in cisplatin-resistant NSCLC cells, leading to the promotion of mitochondrial apoptosis induced by cisplatin. Interestingly, our date indicated the obatoclax also reversed the cross-resistance in cisplatin-resistant NSCLC cells. Therefore, we demonstrated that the targeted therapy with MCL-1 inhibitors, such as obatoclax, may represent a novel strategy for cancer therapy.

Relationship between enzyme adsorption and enzyme-catalyzed degradation of polylactides.

The adsorption of proteinase K on PLLA and PDLA films was studied by CA, surface tension, and microscopic measurements. ESEM clearly shows that proteinase K can irreversibly adsorb on PLLA film. In contrast, no enzyme adsorption was detected on PDLA film under the same conditions. The CA of PLLA film rapidly decreases after immersion in Tris buffer containing proteinase K, whereas that of PDLA remains unchanged. These findings indicate that enzyme adsorption may be a prerequisite for enzymatic degradation of polylactide substrates. Surface tension measurements allow calculation of the average area occupied per proteinase K molecule. The results show that the enzyme molecules exhibit a more compact conformation at higher temperature.

Micelles formed by self-assembling of polylactide/poly(ethylene glycol) block copolymers in aqueous solutions.

Copolymers of polylactide (PLA) and poly(ethylene glycol) (PEG) were synthesized by ring-opening polymerization of L- or D-lactide in the presence of mono- or dihydroxyl PEG using nontoxic zinc lactate as catalyst. The resulting diblock and triblock copolymers were characterized by various analytical techniques such as SEC, (1)H NMR, XRD, and DSC. Bioresorbable micelles were prepared from aqueous solutions of the various copolymers without using any organic solvent. The mixed micellar solutions containing both L-PLA/PEG and D-PLA/PEG copolymers appeared more stable than the separate solutions according to critical micellar concentration (CMC) results, which could be assigned to stronger interactions between L-PLA and D-PLA blocks. The properties of the polymeric micelles strongly depend on the chain structure and composition of the copolymers. CMC values in the presence of salt and at 37 degrees C suggested that the micelles could exhibit good stability in vivo. Thermodynamic parameters calculated from the dependence of CMC on temperature indicate that the micellization process is spontaneous and driven by entropy gain. Dynamic light scattering (DLS) measurements showed one or two populations of micelles for dilute and concentrated solutions, the micelle size decreasing upon dilution. TEM confirmed the presence of micelles, but the size estimated from TEM was smaller than that from DLS due to the dehydration and shrinkage during drying.

Laparoscopic splenectomy: the latest technical evaluation.

AIM: To introduce our latest innovation on technical manipulation of laparoscopic splenectomy. METHODS: Under general anesthesia and carbon dioxide (CO(2)) pneumoperitoneum, 86 cases of laparoscopic splenectomy (LS) were performed. The patients were placed in three different operative positions: 7 cases in the lithotomic position, 31 cases in the right recumbent position and 48 cases in the right lateral position. An ultrasonic scissors was used to dissect the pancreaticosplenic ligament, the splenocolicum ligament, lienorenal ligament and the lienophrenic ligament, respectively. Lastly, the gastrosplenic ligament and short gastric vessels were dissected. The splenic artery and vein were resected at splenic hilum with Endo-GIA. The impact of different operative positions, spleen size and other events during the operation were studied. RESULTS: The laparoscopic splenectomy was successfully performed on all 86 patients from August 1997 to August 2002. No operative complications, such as peritoneal cavity infection, massive bleeding after operation and adjacent organs injured were observed. There was no death related to the operation. The study showed that different operative positions could significantly influence the manipulation of LS. The right lateral position had more advantages than the lithotomic position and the right recumbent position in LS. CONCLUSION: Most cases of LS could be accomplished successfully when patients are placed in the right lateral position. The right lateral position has more advantages than the conventional supine approach by providing a more direct view of the splenic hilum as well as other important anatomies. Regardless of operation positions, the major axis of spleen exceeding 15 cm by B-ultrasound in vitro will surely increase the difficulties of LS and therefore prolong the duration of operation. LS is a safe and feasible modality for splenectomy.

Changes in the level of serum liver enzymes after laparoscopic surgery.

AIM: The purpose of this study was to investigate the effect of laparoscopic surgery on liver function in humans and the possible mechanisms behind such effect. METHODS: Blood samples from 286 patients who underwent laparoscopic cholecystectomy (LC) and 40 patients who underwent open cholecystectomy (OC) were tested for liver function by measuring the level of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) before and after the operations. The same tests were also applied to 18 laparoscopic colorectal cancer resection (LCR) patients and 23 open colorectal cancer resection (OCR) patients to determine whether CO(2) pneumoperitoneum could alter the serum liver enzymes. RESULTS: The level of serum ALT and AST increased significantly during the first 48 hours post operations in both LC and LCR patients. However, no significant change of the serum liver enzymes was detected in both OC and OCR patients. As a result, there was statistically significant difference in change of both ALT and AST levels between LC and OC patients and LCR and OCR patients, respectively. By the 7(th) day post operation, the level of both enzymes returned to normal values in LC, OC and OCR patients except LCR patients whose enzymes remained at a higher level. CONCLUSION: Transient elevation of hepatic transaminases occurred after laparoscopic surgery. The major causative factor seemed to be the CO(2) pneumoperitoneum. In most of the laparoscopic surgery patients, the transient elevation of serum liver enzymes showed no apparent clinical implications. However, if preoperative liver function was very poor, laparoscopic surgery may not be the best choice for the treatment of patients with certain abdominal diseases.

[Laparoscopic colorectomy for colorectal cancer].

OBJECTIVE: To evaluate the result of laparoscopic colorectomy in treatment of colorectal cancer. METHODS: Laparoscopic colorectal surgery was performed in 78 patients with colorectal cancer. Operative procedures, complications and postoperative recovery were studied. RESULT: None of the 78 patients died of laparoscopic colorectal surgery or complications. Eleven patients died from tumor metastasis and 2 from other causes. Twenty-one, 17, 8 patients for 1, 3, 5 years survived respectively. In nine patients who had received operation less than 1 year, no tumor recurrence or metastasis was found except in 1 patient 11 months after operation. CONCLUSION: Laparoscopic colorectal cancer resection is essential to colectomy for colon and rectum cancer when indicated.