In Vivo Ultrasound Shear Wave Elastography Assessment of Acute Compartment Syndrome in a Turkey Model.

OBJECTIVE: The aim of the work described here was to evaluate the objectivity and reproducibility of non-invasive intra-compartment pressure (ICP) measurement using ultrasound shear wave elastography (SWE) in a turkey model in vivo and to determine the biological and histologic changes in acute compartment syndrome (ACS). METHODS: Twenty-four turkeys were randomly divided into four groups based on the duration and fasciotomy of ACS created by infusion of up to 50 mm Hg in the tibialis muscle: group 1, ACS 2 h; group 2, ACS 4 h; group 3, ACS 2 h + fasciotomy 2 h; group 4, ACS 4 h + fasciotomy 2 h. For each turkey, the contralateral limb was considered the control. Time-synchronized measures of SWE and ICP from each leg were collected. Then turkeys were euthanized for histology and quantitative reverse transcription polymerase chain reaction (qRT-PCR) examination. RESULTS: All models created reproducible increases in ICP and SWE, which had a strong linear relationship (r = 0.802, p < 0.0001) during phase 1. SWE remained stable (50.86 ± 9.64 kPa) when ICP remained at 50.28 ± 2.17 mm Hg in phase 2. After fasciotomy, SWE declined stepwise and then normalized (r = 0.737, p < 0.0001). Histologically, the myofiber diameter of group 2 (82.31 ± 22.92 µm) and group 4 (90.90 ± 20.48 µm) decreased significantly (p < 0.01) compared with that of the control group (103.1 ± 20.39 µm); the interstitial space of all groups increased significantly (p < 0.01). Multifocal muscle damage revealed neutrophilic infiltration, degeneration, hemorrhage and necrosis, especially in group 4. Quantitative RT-PCR verified that interleukin-6 and heparin-binding EGF-like growth factor were significantly increased in group 4. CONCLUSION: SWE provided sensitive measurements correlating to ICP in a clinically relevant ACS animal model. Once ACS time was exceeded, progression to irreversible necrosis continued spontaneously, even after fasciotomy. SWE may help surgeons in the early detection, monitoring, prognosis and decision making on fasciotomy for ACS.

Clinicopathological features and expression of regulatory mechanism of the Wnt signaling pathway in colorectal sessile serrated adenomas/polyps with different syndrome types.

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide, with the fourth highest mortality among all cancers. Reportedly, in addition to adenomas, serrated polyps, which account for 15%-30% of CRCs, can also develop into CRCs through the serrated pathway. Sessile serrated adenomas/polyps (SSAs/Ps), a type of serrated polyps, are easily misdiagnosed during endoscopy. AIM: To observe the difference in the Wnt signaling pathway expression in SSAs/Ps patients with different syndrome types. METHODS: From January 2021 to December 2021, patients with SSAs/Ps were recruited from the Endoscopy Room of Shanghai Traditional Chinese Medicine-Integrated Hospital, affiliated with Shanghai University of Traditional Chinese Medicine. Thirty cases each of large intestine damp-heat (Da-Chang-Shi-Re, DCSR) syndrome and spleen-stomach weakness (Pi-Wei-Xu-Ruo) syndrome were reported. Baseline comparison of the general data, typical tongue coating, colonoscopy findings, and hematoxylin and eosin findings was performed in each group. The expression of the Wnt pathway-related proteins, namely ß-catenin, adenomatous polyposis coli, and mutated in colorectal cancer, were analyzed using immunohistochemistry. RESULTS: Significant differences were observed with respect to the SSAs/Ps size between the two groups of patients with different syndrome types (P = 0.001). The other aspects did not differ between the two groups. The Wnt signaling pathway was activated in patients with SSAs/Ps belonging to both groups, which was manifested as ß-catenin protein translocation into the nucleus. However, SSAs/Ps patients with DCSR syndrome had more nucleation, higher ß-catenin expression, and negative regulatory factor (adenomatous polyposis coli and mutated in colorectal cancer) expression (P < 0.0001) than SSA/P patients with Pi-Wei-Xu-Ruo syndrome. In addition, the SSA/P size was linearly correlated with the related protein expression. CONCLUSION: Patients with DCSR syndrome had a more obvious Wnt signaling pathway activation and a higher risk of carcinogenesis. A high-quality colonoscopic diagnosis was essential. The thorough assessment of clinical diseases can be improved by combining the diseases of Western medicine with the syndromes of traditional Chinese medicine.

GBP2 as a potential prognostic predictor with immune-related characteristics in glioma.

Guanylate binding protein 2 (GBP2) is a member of the guanine binding protein family, and its relationship with prognostic outcomes and tumor immune microenvironments in glioma remains elusive. We found GBP2 were increased in glioma tissues at both mRNA and protein levels. Kaplan-Meier curves revealed that high GBP2 expression was linked with worse survival of glioma patients, and multivariate Cox regression analysis indicated that high GBP2 expression was an independent prognostic factor for glioma. Combined analysis in immune database revealed that the expression of GBP2 was significantly related to the level of immune infiltration and immunomodulators. Single-cell analysis illustrated the high expression of GBP2 in malignant glioma cells showed the high antigen presentation capability, which were confirmed by real-time polymerase chain reaction (qRT-PCR) data. Additionally, the hsa-mir-26b-5p and hsa-mir-335-5p were predicted as GBP2 regulators and were validated in U87 and U251 cells. Our results first decipher immune-related characteristics and noncoding regulators of GBP2 in glioma, which may provide insights into associated immunotherapies and prognostic predictor.

Superior results of return to sport after double-bundle versus single-bundle anterior cruciate ligament reconstruction in young active patients.

PURPOSE: To compare return to sport and clinical results in young active patients who underwent anatomic single-bundle (SB) versus double-bundle (DB) anterior cruciate ligament reconstruction (ACLR). METHODS: Young active patients undergoing SB or DB ACLR from 2017 to 2019 at our institution were retrospectively reviewed. The primary outcome measures were the rate and time to return to sports, with secondary measures including the Lachman test, pivot shift test, Lysholm scores, International Knee Documentation Committee (IKDC) scores and graft rupture. RESULTS: The study included a total of 90 patients (DB group, 42; SB group, 48), with a mean follow-up of 27.1 ± 6.1 months. Young active patients who underwent DB ACLR had a higher rate of return to pivoting sports than those who underwent SB ACLR (HR = 2.4; 95% confidence interval [CI]: 1.4, 4.1; p = 0.013). The DB group returned to pivoting sports at a mean ± SD of 11.0 ± 2.9 months compared with 12.7 ± 2.7 months in the SB group (p = 0.01). There was one traumatic failure in the SB group and one contralateral ACL rupture in the DB group. There was no significant difference in the rate and time to return to running, Lachman test, pivot-shift test, Lysholm or IKDC scores in either group. CONCLUSION: Both anatomical SB and DB techniques achieved satisfactory clinical outcomes. DB techniques led to superior performance of return to pivoting sports but nonsignificant differences in time and rate of return to running, passive stability measurement, subjective knee function outcome and graft rupture rate in both groups at the 2-year follow-up. The DB ACLR should be considered a viable option to treat young patients with high activity demands. LEVEL OF EVIDENCE: III.

FRAT1 promotes the angiogenic properties of human glioblastoma cells via VEGFA.

Glioblastoma is a common central nervous system tumor and despite considerable advancements in treatment patient prognosis remains poor. Angiogenesis is a significant prognostic factor in glioblastoma, anti­angiogenic treatments represent a promising therapeutic approach. Vascular endothelial growth factor A (VEGFA) is a predominant regulator of angiogenesis and mounting evidence suggests that the Wnt signaling pathway serves a significant role in tumor angiogenesis. As a positive regulator of the Wnt/ß­catenin signaling pathway, frequently rearranged in advanced T­cell lymphomas­1 (FRAT1) is highly expressed in human glioblastoma and is significantly associated with glioblastoma growth, invasion and migration, as well as poor patient prognosis. Bioinformatics analysis demonstrated that both VEGFA and FRAT1 were highly expressed in most tumor tissues and associated with prognosis. However, whether and how FRAT1 is involved in angiogenesis remains to be elucidated. In the present study, the relationship between FRAT1 and VEGFA in angiogenesis was investigated using the human glioblastoma U251 cell line. Small interfering RNAs (siRNAs) were used to silence FRAT1 expression in U251 cells, and the mRNA and protein expression levels of VEGFA, as well as the concentration of VEGFA in U251 cell supernatants, were determined using reverse transcription­quantitative PCR, western blotting and ELISA. A tube formation assay was conducted to assess angiogenesis. The results demonstrated that siRNA knockdown significantly decreased the protein expression levels of FRAT1 in U251 cells and markedly decreased the mRNA and protein expression levels of VEGFA. Furthermore, the concentration of VEGFA in the cell supernatant was significantly reduced and angiogenesis was suppressed. These results suggested that FRAT1 may promote VEGFA secretion and angiogenesis in human glioblastoma cells via the Wnt/ß­catenin signaling pathway, supporting the potential use of FRAT1 as a promising therapeutic target in human glioblastoma.

Effects of purified exosome product on rotator cuff tendon-bone healing in vitro and in vivo.

Exosomes have multiple therapeutic targets, but the effects on healing rotator cuff tear (RCT) remain unclear. As a circulating exosome, purified exosome product (PEP) has the potential to lead to biomechanical improvement in RCT. Here, we have established a simple and efficient approach that identifies the function and underlying mechanisms of PEP on cell-cell interaction using a co-culture model in vitro. In the in vivo trial, adult female Sprague-Dawley rats underwent unilateral surgery to transect and repair the supraspinatus tendon to its insertion site with or without PEP. PEP promoted the migration and confluence of osteoblast cells and tenocytes, especially during direct cell-cell contact. Expression of potential genes for RCT in vitro and in vivo models were consistent with biomechanical tests and semiquantitative histologic scores, indicating accelerated strength and healing of the RC in response to PEP. Our observations suggest that circulating exosomes provide an effective option to improve the healing speed of RCT after surgical repair. The regeneration of enthesis following PEP treatment appears to be related to a mutually reinforcing relationship between direct cell-cell contact and PEP activity, suggesting a dual approach to the healing process.

A useful intraoperative technique for transiliac-transsacral screws: a point-to-point coaxial guide apparatus.

BACKGROUND: The transiliac-transsacral screw placement is a clinical challenge for surgeons. This study explored a point-to-point coaxial guide apparatus assisting the transiliac-transsacral screw insertion and aimed to investigate the feasibility and accuracy of the guide apparatus in the treatment of posterior ring unstable pelvic fracture compared with a free-hand technique. METHODS: A retrospective study was performed to evaluate patients treated with transiliac-transsacral screws assisted by the point-to-point coaxial guide apparatus or free-hand technique. The intraoperative data of operative time and radiation exposure times were recorded. Postoperative radiographs and CT scans were performed to scrutinize the accuracy of screws position. The quality of the postoperative fracture reduction was assessed according to Matta radiology criteria. The pelvic function was assessed according to the Majeed scoring criteria at 6 months postoperatively. RESULTS: From July 2017 to December 2019, a total of 38 patients were included in this study, 20 from the point-to-point guide apparatus group and 18 from the free-hand group. There were no significant differences between the two groups in gender, age, injury causes, pelvic fracture type, screws level, and follow-up time (P > 0.05). The average operative time of the guide apparatus group for each screw was significantly less than that in the free-hand group (25.8 ± 4.7 min vs 40.5 ± 5.1, P < 0.001). The radiation exposure times were significantly lower in the guide apparatus group than that in the free-hand group (24.4 ± 6.0 vs 51.6 ± 8.4, P < 0.001). The intraosseous and juxtacortical rate of screw placement (100%) higher than in the free-hand group (94.4%). CONCLUSION: The point-to-point coaxial guide apparatus is feasible for assisting the transiliac-transsacral screw in the treatment of posterior unstable pelvic fractures. It has the advantages of simple operation, reasonable design and no need for expensive equipment, and provides an additional surgical strategy for the insertion of the transiliac-transsacral screw.

Temporal-spatial characteristics of phase-amplitude coupling in electrocorticogram for human temporal lobe epilepsy.

OBJECTIVE: Neural activity of the epileptic human brain contains low- and high-frequency oscillations in different frequency bands, some of which have been used as reliable biomarkers of the epileptogenic brain areas. However, the relationship between the low- and high-frequency oscillations in different cortical areas during the period from pre-seizure to post-seizure has not been completely clarified. METHODS: We recorded electrocorticogram data from the temporal lobe and hippocampus of seven patients with temporal lobe epilepsy. The modulation index based on the Kullback-Leibler distance and the phase-amplitude coupling co-modulogram were adopted to quantify the coupling strength between the phase of low-frequency oscillations (0.2-10Hz) and the amplitude of high-frequency oscillations (11-400Hz) in different seizure epochs. The time-varying phase-amplitude modulogram was used to analyze the phase-amplitude coupling pattern during the entire period from pre-seizure to post-seizure in both the left and right temporal lobe and hippocampus. Channels with strong modulation index were compared with the seizure onset channels identified by the neurosurgeons and the resection channels in the clinical surgery. RESULTS: The phase-amplitude coupling strength (modulation index) increased significantly in the mid-seizure epoch and decrease significantly in seizure termination and post-seizure epochs (p<0.001). The strong phase-amplitude-modulating low- and high-frequency oscillations in the mid-seizure epoch were mainly δ, θ, and α oscillations and γ and ripple oscillations, respectively. The phase-amplitude modulation and strength varied among channels and was asymmetrical in the left and right temporal cortex and hippocampus. The "fall-max" phase-amplitude modulation pattern, i.e., high-frequency amplitudes were largest in the low-frequency phase range [-π, 0], which corresponded to the falling edges of low-frequency oscillations, appeared in the middle period of the seizures at epileptic focus channels. Channels with strong modulation index appeared on the corresponding left or right temporal cortex of surgical resection and overlapped with the clinical resection zones in all patients. CONCLUSIONS: The "fall-max" pattern between the phase of low-frequency oscillation and amplitude of high-frequency oscillation that appeared in the middle period of the seizures is a reliable biomarker in epileptogenic cortical areas. The modulation index can be used as a good tool for lateralization and localization for the epileptic focus in patients with epilepsy. SIGNIFICANCE: Phase-amplitude coupling can provide meaningful reference for accurate resection of epileptogenic focus and provide insight into the underlying neural dynamics of the epileptic seizure in patients with temporal lobe epilepsy.

Autocrine and paracrine STIP1 signaling promote osteolytic bone metastasis in renal cell carcinoma.

Bone metastases are responsible for some of the most devastating complications of renal cell carcinoma (RCC). However, pro-metastatic factors leading to the highly osteolytic characteristics of RCC bone metastasis have barely been explored. We previously developed novel bone-seeking RCC cell lines by the in vivo selection strategy and performed a comparative proteome analysis on their total cell lysate. Here, we focused on STIP1 (stress-induced phosphoprotein 1), the high up-regulated protein in the bone-seeking cells, and explored its clinical relevance and functions in RCC bone metastasis. We observed high levels of both intracellular and extracellular STIP1 protein in bone metastatic tissue samples. Elevated STIP1 mRNA in the primary RCC tumors remarkably correlated with worse clinical outcomes. Furthermore, both human recombinant STIP1 protein and anti-STIP1 neutralizing antibody were used in the functional studies. We found that 1) STIP1 protein on the extracellular surface of tumor cells promoted the proliferation and migration/invasion of RCC tumor cells through the autocrine STIP1-ALK2-SMAD1/5 pathway; and 2) STIP1 protein secreted into the extracellular tumor stromal area, promoted the differentiation of osteoclasts through the paracrine STIP1-PrPc-ERK1/2 pathway. Increased cathepsin K (CTSK), the key enzyme secreted by osteoclasts to degrade collagen and other matrix proteins during bone resorption was further detected in the differentiated osteoclasts. These results provide evidence of the great potential of STIP1 as a novel biomarker and therapeutic target in RCC bone metastasis.

Crosstalk between ATF4 and MTA1/HDAC1 promotes osteosarcoma progression.

The stress response gene activating transcription factor 4 (ATF4) is involved in metastatic behavior and cellular protection. Here we show that ATF4 is upregulated in osteosarcoma (OS) cell lines and patient clinical samples as compared to matched non-tumor tissue. Overexpression of ATF4 in OS cells promoted cell proliferation, migration and lung metastasis. Furthermore, the expression of ATF4 was markedly reduced in metastasis associated protein (MTA1) or histone deacetylase 1 (HDAC1) knockdown OS cells, but MTA1 overexpression increased the stability and activity of ATF4 protein via ATF4 deacetylation by HDAC1. ATF4 in turn enhanced the expression of MTA1 and HDAC1 at the transcription level, suggesting a positive feedback loop between ATF4 and MTA1/HDAC1. Clinically, the level of ATF4 was positively correlated with that of MTA1 in OS. Mice injected with ATF4-overexpressing cells exhibited a higher rate of tumor growth, and the average weight of these tumors was ~90% greater than the controls. Taken together, these data establish a direct correlation between ATF4-induced OS progression and MTA1/HDAC1-associated metastasis, and support the potential therapeutic value of targeting ATF4 in the treatment of OS.

Eight proteins play critical roles in RCC with bone metastasis via mitochondrial dysfunction.

Most kidney cancers are renal cell carcinomas (RCC). RCC lacks early warning signs and 70 % of patients with RCC develop metastases. Among them, 50 % of patients having skeletal metastases developed a dismal survival of less than 10 % at 5 years. Therefore, exploring the key driving proteins and pathways involved in RCC bone metastasis could benefit patients' therapy and prolong their survival. We examined the difference between the OS-RC-2 cells and the OS-RC-2-BM5 cells (subpopulation from OS-RC-2) of RCC with proteomics. Then we employed Western-blot, immunohistochemistry and the clinical database (oncomine) to screen and verify the key proteins and then we analyzed the functions and the related pathways of selected key proteins with system biology approaches. Our proteomic data revealed 26 significant changed spots (fold change <0.5 and >1.9, P < 0.05) between two cells. The Western blotting results validated for these identified spots were consistent with the proteomics'. From the public clinical database, 23 out of 26 proteins were connected with RCC metastases and 9 out of 23 with survival time directly (P < 0.05). Finally, only 8 out of 9 proteins had significantly positive results in tissues of RCC patients with bone metastasis compared with primary tumor (P < 0.05). System biology analyzing results showed these eight proteins mainly distributed in oxidative phosphorylation which indicates that mitochondria dysfunction played the critical role to regulate cells metastasis. Our article used a variety of experimental techniques to find eight proteins which abnormally regulated mitochondrial function to achieve a successful induction for RCC metastasis to bone.

Alterations in enhancer of zeste homolog 2, matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 expression are associated with ex vivo and in vitro bone metastasis in renal cell carcinoma.

Renal cell carcinoma (RCC) has a high potential for bone metastasis; however, the molecular mechanisms underlying this metastasis have remained to be elucidated. The present study aimed to explore the expression levels of enhancer of zeste homolog 2 (EZH2), matrix metalloproteinase-2 (MMP2) and tissue inhibitor of metalloproteinase-2 (TIMP2) as determinants of RCC-associated bone metastasis. Their expression was evaluated in a newly generated RCC cell subline that has a high potential for bone metastasis, in tissue specimens from metastasized bone tissues from patients with RCC and in RCC tissues without metastasis. A total of 25 RCC tissue specimens without metastasis and 13 RCC tissue specimens with bone metastasis were acquired for immunohistochemical analysis of EZH2, MMP2 and TIMP2 protein expression. The expression levels of EZH2, MMP2 and TIMP2 mRNA and protein were analyzed in the ACHN and ACHN-BO5 cell lines using western blot and reverse transcription polymerase chain reaction (PCR) analyses. Methylation-specific PCR was also used to analyze TIMP2 promoter methylation. EZH2 and MMP2 proteins were found to be expressed at higher levels in tissues from patients where RCC had metastasized to the bone as compared with those in RCC patients without metastasis, whereas there was no significant difference in the expression of TIMP2 protein between the two tissues. Furthermore, the expression of EZH2 protein was correlated with MMP2 expression, but there was no significant correlation between the expression of EZH2 and TIMP2 proteins. The in vitro results using cell lines confirmed the ex vivo findings, indicating that the expression levels of EZH2 and MMP2 protein and mRNA were higher in ACHN-BO5 cells than those in ACHN cells. By contrast, TIMP2 protein and mRNA expression levels were lower in ACHN-BO5 cells than those in the parental ACHN cells. The TIMP2 promoter was highly methylated in ACHN-BO5 cells compared with that in ACHN cells. Upregulation of EZH2, MMP2 and TIMP2 expression was correlated with metastasis of RCC to bone tissues ex vivo and in vitro. Further studies are required in order to elucidate the mechanism underlying the altered expression of these genes.

Suppressive effects of induced pluripotent stem cell-conditioned medium on in vitro hypertrophic scarring fibroblast activation.

Hypertrophic scarring (HS) is a type of fibrosis that occurs in the skin, and is characterized by fibroblast activation and excessive collagen production. However, at present, therapeutic strategies for this condition are ineffective. Previous studies have identified that the mutual regulation of chronic inflammation, mechanical force and fibroblast activation leads to the formation of HS. Induced pluripotent stem cells (iPSCs) are novel bioengineered embryonic­like stem cells, initially created from mouse adult fibroblasts. The current study demonstrated that iPSC­conditioned medium (iPSC­CM) may significantly suppress hypertrophic scar fibroblast activation. It was observed that in the presence of iPSC­CM, the level of collagen I was markedly reduced and α­smooth muscle actin, a marker for myofibroblasts (activated fibroblasts that mediate mechanical force­induced HS formation), exhibited a significantly lower level of expression in human dermal fibroblasts (HDFs) activated with transforming growth factor­ß1. Additionally, iPSC­CM attenuated the local inflammatory cell response by blocking the adhesion of human acute monocytic leukemia cell monocytes and fibroblasts in vitro. In addition, the contractile ability of HDFs may be reduced by iPSC­CM. These observations suggest that iPSC­CM may protect against processes leading to hypertrophic scarring by attenuating fibroblast activation, blocking inflammatory cell recruitment and adhesion and reducing the contractile ability of fibroblasts.

Successful treatment of recurrent Kimura's disease with radiotherapy: a case report.

Kimura's disease is a rare, chronic inflammatory disorder affecting the skin and subcutaneous tissue, predominantly in the head and neck region. It is benign but may be recurrent and difficult to eradicate. A case of recurrent Kimura disease in a 53-year-old man was reported. Radiation therapy was performed for recurrence after surgical excision twice. The prescribed radiation dose was 36 Gy. With a follow-up time of 68 months, the patient was free of the disease.

Decreased osteoclastogenesis, osteoblastogenesis and low bone mass in a mouse model of type 2 diabetes.

The effect of type 2 diabetes mellitus (T2DM) on bone is controversial. Therefore, the present study investigated whether T2DM causes osteoporosis and explored the underlying mechanisms involved in this process. The effects of T2DM on bone physiology were analyzed in a mouse model of T2DM; KK/Upj­Ay/J (KK­Ay) mice develop diabetes after 8 weeks and exhibit stable diabetes symptoms and signs after 10 weeks when fed a KK­Ay mouse maintenance fodder. Diabetic mice exhibited hyperglycemia, hyperinsulinemia and increased body and fat pad weight in comparison with C57BL/6 non-diabetic mice. Furthermore, diabetic mice demonstrated low bone weight and bone mineral density in the femur, tibia and fifth lumbar vertebra. Using von Kossa and tartrate-resistant acid phosphatase (TRAP) staining, alkaline phosphatase and TRAP activity analyses and gene profiling it was demonstrated that osteoblastogenesis and osteoclastogenesis were impaired in diabetic mice. To evaluate the bone biomechanics, the ultimate load of the bone was analyzed. It was found that the ultimate load of the tibia in diabetic mice was lower than that in the controls. The results from the present study suggest that bone metabolism is impaired in T2DM, resulting in decreased osteoblastogenesis, osteoclastogenesis and bone mass.

Metformin inhibits histone H2B monoubiquitination and downstream gene transcription in human breast cancer cells.

Metformin, one of the most widely prescribed antihyperglycemic drugs, has recently received increasing attention for its potential effects with regard to cancer prevention and treatment. However, the mechanisms behind the suppression of cancer cell growth by metformin remain far from completely understood. The aim of the present study was to investigate whether metformin could regulate histone modification and its downstream gene transcription, and its potential function in inhibiting breast cancer cell proliferation. A T47D cell proliferation curve was determined by cell counting following metformin treatment with differing doses or time courses. The cell cycle was analyzed by flow cytometry with propidium iodide staining. Histone H2B monoubiquitination was evaluated by western blotting subsequent to histone extraction. The histone H2B monoubiquitination downstream gene expression level was determined by quantitative PCR. The results showed that metformin changed the cell-cycle check-point and inhibited breast cancer cell proliferation in a dose-dependent manner. AMPK was activated and histone H2B monoubiquitination and downstream gene transcription were inhibited following metformin treatment in the T47D cells. The effect of metformin on T47D cell proliferation was dependent on AMPK activity. It was concluded that metformin can suppress breast cancer cell growth by the activation of AMPK and the inhibition of histone H2B monoubiquitination and downstream gene transcription. This study reveals a novel potential mechanism of cancer cell growth suppression by metformin.

Peroxisome proliferator­activated receptor γ agonist rosiglitazone inhibits migration and invasion of prostate cancer cells through inhibition of the CXCR4/CXCL12 axis.

It has been indicated that the C­X­C chemokine receptor type 4/C­X­C chemokine ligand 12 (CXCR4/CXCL12) axis is involved in promoting invasion and metastasis in tumors. Therefore, novel drugs capable of downregulating the CXCR4/CXCL12 axis may demonstrate potential for the treatment of metastatic prostate cancer (PCa). Rosiglitazone (RSG), a thiazolidinedione ligand of the peroxisome proliferator­activated receptor (PPAR) Î³, has been found to inhibit proliferation, induce apoptosis, suppress angiogenesis and inhibit metastasis. However, the precise mechanisms by which RSG regulates CXCR4 gene expression and the consequent effects on prostate cell migration and invasion are not fully understood. In this study, it was observed that RSG is capable of downregulating the expression of CXCR4 in PCa cells in a dose­, time­ and PPARγ­dependent manner. Furthermore, it was observed that the downregulation of CXCR4 expression occurred at a transcriptional level, as indicated by a reduction in CXCR4 mRNA expression. Suppression of CXCR4 expression by RSG further correlated with the inhibition of CXCL12­induced migration and invasion in PCa cells. Analysis of the predominant intracellular signaling pathways that act downstream of the activated CXCR4/CXCL12 axis, namely the phosphatidyl inositol 3­kinase (PI3K)­protein kinase B (Akt) cascades, revealed that RSG rapidly interferes with the phosphorylation/activation of Akt, which mediates CXCL12­stimulated migration and invasion. Overall, the findings of this study suggest that RSG represents a novel inhibitor of CXCR4 expression and, thus, has significant potential as a powerful therapeutic agent for the treatment of metastatic PCa.

Peroxisome proliferator-activated receptor γ ligands inhibit VEGF-mediated vasculogenic mimicry of prostate cancer through the AKT signaling pathway.

Vasculogenic mimicry (VM) describes functional vascular channels composed only of tumor cells and its presence predicts a poor prognosis for patients with prostate cancer. The present study demonstrated that prostate cancer PC-3 cells were able to form a patterned matrix or tubular VM in 3D cultures in vitro and rosiglitazone (RSG), the ligand of peroxisome proliferator-activated receptor Î³ (PPARγ) and effectively inhibited the formation of VM structures in a dose- and PPARγ­dependent manner. In addition, RSG significantly inhibited prostate cancer cell migration and invasion. The inhibitory effect of RSG on VM formation could be at least partially explained by an RSG-driven downregulation of vascular endothelial growth factor (VEGF) levels and phosphorylation of AKT, which is known to be important in VM. Furthermore, the present study highlighted that VEGF and the phosphoinositide 3-kinase/AKT pathway exert a positive feedback regulation in the process of VM formation. These findings reveal new therapeutic potential for PPARγ ligands in anti­cancer therapy.

SCP, a polysaccharide from Schisandra chinensis, induces apoptosis in human renal cell carcinoma Caki-1 cells through mitochondrial-dependent pathway via inhibition of ERK activation.

This study is the first to investigate the anticancer effect of Schisandra chinensis polysaccharide (SCP) in renal cell carcinoma (RCC) cells. The results revealed that SCP treatment showed high cytotoxic potency in Caki-1 cells by inducing apoptosis, which is associated with the disruption of mitochondrial membrane potential (MMP), release of cytochrome c into the cytosol, increase of Bax/Bcl-2 ratio, activation of caspase-3/9, and cleavage of poly(ADP-ribose) polymerase (PARP). Furthermore, pan-caspase inhibitor (z-VAD-fmk) significantly blocked SCP-induced apoptosis and PARP cleavage in Caki-1 cells. As well, we also observed that SCP inhibited the phosphorylation of ERK1/2, whereas it had no significant inhibition effect on the phospho-p38 and phospho-JNK activity. All the above parameters provided scientific evidence that SCP induced mitochondrial-mediated apoptosis in Caki-1 cells through the inactivation of ERK pathways, which may shed further light on its potential application as a cancer chemopreventive agent against RCC.

Protein-energy wasting and peritoneal function in elderly peritoneal dialysis patients.

BACKGROUND: Nutritional status is important in peritoneal dialysis (PD) patients. We aimed to compare the peritoneal transport (PT) characteristics and indicators of nutritional status in elderly and non-elderly PD patients. METHODS: One-hundred and four consecutive patients were divided into either the elderly (>65 years old; n = 44) or the non-elderly (≤65 years old; n = 60) group. PT was assessed via the peritoneal equilibration test, Kt/V (K dialyzer clearance of urea, t dialysis time, V volume of distribution of urea), total creatinine clearance (CrCl), and glomerular filtration rate. Subjective global assessment (SGA), serum albumin (ALB), hemoglobin, prealbumin (PA), transferrin (TF), fat-free edema-free body mass (fat-free edema-free BM), and normalized protein intake (nPNA) were determined, and were used to indicate nutritional status. RESULTS: Elderly PD patients had higher dialysate to plasma creatinine ratios (D/P Cr) and CrCl, but lower serum creatinine body weights, ALB, PA, TF, fat-free edema-free BM, SGA, and nPNA than the non-elderly group. Multivariate analysis indicated that, after adjusting for PD time, body weight, diabetes mellitus, age, and sex, SGA negatively correlated with D/P Cr, whereas after adjusting for PD time, diabetes mellitus, and sex, D/P Cr positively correlated with age in all patients. CONCLUSIONS: Protein-energy wasting and a high PT are more common in elderly than non-elderly PD patients. Nutritional status should be carefully considered when prescribing the PD dose and frequency, especially in elderly patients.