Percutaneous Mechanical Thrombectomy Using the AcoStream Thrombus Aspiration System for Acute Superior Mesenteric Artery Embolism.

BACKGROUND: This study was performed to summarize our experience in treating acute superior mesenteric artery embolism (SMAE) by percutaneous mechanical thrombectomy (PMT). METHODS: Between January 2023 and October 2023, 18 patients presenting with acute mesenteric ischemia were admitted to our center, including 11 cases of SMAE, 3 cases of superior mesenteric artery thrombosis, and 4 cases of superior mesenteric vein thrombosis. We retrospectively reviewed 8 patients (4 males and 4 females; range, 51-79 years; mean, 62.50 ± 9.67 years) who underwent treatment of acute SMAE using the AcoStream system. The patients had no obvious evidence of intestinal necrosis as shown by peritoneal puncture or computed tomography. Thrombectomy was performed on the superior mesenteric artery (SMA) using an 8F AcoStream thrombus aspiration system (Acotec, China). The demographics, risk factors, therapeutic effect, complications, mortality, and follow-up of the study population were assessed. RESULTS: The technical success rate was 100%. After 1-3 passes (2.38 ± 0.92) and aspiration thrombectomy, complete thrombus removal was achieved in 7 (87.50%) patients. One patient received an adjunctive catheter-directed thrombolysis due to partial thrombus removal. Thrombolysis was conducted for 2 days, resulting in complete resolution of the thrombus. The other 7 patients did not receive adjunctive endovascular intervention due to complete thrombus removal and no residual stenosis. No distal embolization or device-related complications were noted during the procedure. After the procedure, sufficient clinical improvement was seen in 6 patients within 1-2 days. Two patients showed no significant improvement of their symptoms. Laparotomy was performed on day 1 and day 2 after thrombectomy in patients 3 and 7, respectively. Intestinal necrosis was diagnosed operatively and intestinal resection was performed. All patients were discharged 6-15 days (9.50 ± 3.07) after admission without perioperative complication or death. The mean follow-up period was 5.00 ± 3.30 months (range, 1-10 months), and the follow-up rate was 100%. During the follow-up, all patients remained symptom-free. Computed tomography angiography images showed good flow in the trunk and branches of the SMA in all patients. CONCLUSIONS: PMT using the AcoStream system is a minimally invasive, safe, and effective technique for acute SMAE. Early application of PMT can achieve immediate revascularization of the SMA and have the potential advantage of avoiding laparotomy or reducing the extension of enterectomy, as it could theoretically restore intestinal perfusion in less time than open revascularization. If the symptoms do not improve after PMT, exploratory laparotomy should be scheduled as soon as possible. Further studies are necessary on this field to confirm these findings.

Exosomes derived from human urine-derived stem cells ameliorate IL-1ß-induced intervertebral disk degeneration.

BACKGROUND: Human intervertebral disk degeneration (IVDD) is a sophisticated degenerative pathological process. A key cause of IVDD progression is nucleus pulposus cell (NPC) degeneration, which contributes to excessive endoplasmic reticulum stress in the intervertebral disk. However, the mechanisms underlying IVDD and NPC degeneration remain unclear. METHODS: We used interleukin (IL)-1ß stimulation to establish an NPC-degenerated IVDD model and investigated whether human urine-derived stem cell (USC) exosomes could prevent IL-1ß-induced NPC degeneration using western blotting, quantitative real-time polymerase chain reaction, flow cytometry, and transcriptome sequencing techniques. RESULTS: We successfully extracted and identified USCs and exosomes from human urine. IL-1ß substantially downregulated NPC viability and induced NPC degeneration while modulating the expression of SOX-9, collagen II, and aggrecan. Exosomes from USCs could rescue IL-1ß-induced NPC degeneration and restore the expression levels of SOX-9, collagen II, and aggrecan. CONCLUSIONS: USC-derived exosomes can prevent NPCs from degeneration following IL-1ß stimulation. This finding can aid the development of a potential treatment strategy for IVDD.

Thrap3 promotes osteogenesis by inhibiting the degradation of Runx2.

The dysfunction of osteogenesis is a key character in the pathogenesis of osteoporosis, but the network of signaling mechanisms in controlling the differentiation of osteoblast remain unclear. Thrap3 has been proved participating in various biological process, especially in the differentiation of stem cells. Here, we demonstrate that Thrap3 could promote osteogenesis through the inhibition of the degradation of Runx2, which is a key molecular structure in early osteoblast differentiation. Furthermore, we found that the osteogenesis enhancing capacity of Thrap3 was caused by physically binding with Sox9, inhibiting the transcriptional activity of Sox9, and then decreasing the decomposition-promoted effect of Sox9 on Runx2. Our data shows that Thrap3 promotes osteoblast differentiation through the Thrap3-Sox9-Runx2 axis. What we found may help for further clarifying the molecular mechanism of osteogenic differentiation and give a new potential therapeutic target for osteoporosis.

The Association between Dietary Protein Intake and the Risk of Pancreatic Cancer: Evidence from 14 Publications.

Many studies have been published to assess the association about dietary protein intake on the risk of pancreatic cancer, but with inconsistent result. This meta-analysis aimed to evaluate whether protein intake could affect the risk of pancreatic cancer. A systematic literature search was performed in PubMed, EMBASE and Web of Science up to October 1, 2019. Pooled relative risks (RR) and 95% confidence intervals (CI) were calculated using a random-effect model. A total of 14 studies (12 case-control studies and two cohort studies) were included. Overall, total protein intake had no significant association on the risk of pancreatic cancer (RR = 1.02, 95%CI= 0.85-1.22, I2=45.7%). Subgroup analyses showed such relationships were almost not influenced by study design and geographic location. Interestingly, when we performed the subgroup analysis by protein type, the opposite association was found in animal protein intake (RR = 1.37, 95%CI= 0.93-2.01) and vegetable protein intake (RR = 0.78, 95%CI= 0.54-1.14), although these two groups were not statistically significant. In conclusion, this meta-analysis indicated that dietary total protein intake may be not associated with the risk of pancreatic cancer. However, protein type may be affecting the result which was found from our research. Therefore, studies with detailed information, especially protein type, are warranted to further confirm these findings.

Dok5 regulates proliferation and differentiation of osteoblast via canonical Wnt/ß-catenin signaling.

OBJECTIVE: In bone tissue engineering, the use of osteoblastic seed cells has been widely adopted to mediate the osteogenic differentiation so as to prompt bone regeneration and repair. It is hypothesized that Dok5 can regulate the proliferation and differentiation of osteoblasts. In this study, the role of Dok5 in osteoblast proliferation and differentiation was investigated. METHODS: A lentiviral vector to silence Dok5 was transferred to C3H10, 293T and C2C12 cells. CCK-8 assay was used to detect the cell proliferation. Cells were stained by ALP and AR-S staining. Western blot and RT-PCR were used to detect the expression levels of related factors. RESULTS: Dok5 expression level was gradually up-regulated during the osteoblast differentiation. Dok5 silencing down-regulated the expression levels of osteogenic biosignatures OPN, OCN, and Runx2 and suppressed the osteogenesis. Additionally, the osteoblast proliferation and canonical Wnt/ß-catenin signaling were suppressed upon Dok5 knockdown, ß-catenin expression level was significantly down-regulated in the knockdown group, while the expression levels of GSK3-ß and Axin, negative regulators in the Wnt signaling pathway, were up-regulated. Furthermore, overexpression of Dok5 promoted the proliferation and osteogenesis and activated the canonical Wnt/ß-catenin signaling pathway. CONCLUSION: Dok5 may regulate the osteogenic proliferation and differentiation via the canonical Wnt/ß-catenin signaling pathway.

miR-219a-5p inhibits the pyroptosis in knee osteoarthritis by inactivating the NLRP3 signaling via targeting FBXO3.

PURPOSE: This work was to identify the function and mechanism of miR-219a-5p in regulating knee osteoarthritis (KOA). METHODS: Rat fibroblast-like synoviocytes (FLSs) were isolated to construct KOA cell model by lipopolysaccharide and adenosine triphosphate treatment. miR-219a-5p and FBXO3 expression in FLSs was modulated by transfection. Flow cytometry was executed to research FLSs apoptosis. Caspase-1 and IL-1ß expression in FLSs was researched by immunofluorescence. The binding between miR-219a-5p and FBXO3 was identified by dual luciferase reporter gene assay. KOA rat model and miR-219a-5p up-modulation KOA rat model were constructed. Step size of rats was analyzed. Knee joints of rats were experienced Safranin O-fast green staining to evaluate the knee joint injury. FBXO3, pyroptosis-associated proteins, and IL-1ß and IL-18 expression in FLSs and articular cartilage tissues of rats were assessed by Western blot, qRT-PCR and Enzyme-linked immunosorbent assay. RESULTS: KOA cell model had higher apoptosis percentage, expression of pyroptosis-associated proteins, and IL-1ß and IL-18 level. miR-219a-5p up-modulation decreased the above indicators, whereas miR-219a-5p down-modulation increased the above indicators. FBXO3 expression was directly repressed by miR-219a-5p. Loss of FBXO3 suppressed the above indicators. FBXO3 counteracted the suppression of miR-219a-5p on the above indicators. miR-219a-5p agomir attenuated knee joint injury, increased step size of KOA rats, and reduced FBXO3, pyroptosis-associated proteins and level of IL-1ß and IL-18 in the articular cartilage tissues of KOA rats. CONCLUSION: miR-219a-5p suppressed the pyroptosis in KOA by inactivating the NLRP3 signaling via targeting FBXO3, which might be a promising target for ameliorating KOA in the clinic.

Microfibrillar-associated protein 5 regulates osteogenic differentiation by modulating the Wnt/ß-catenin and AMPK signaling pathways.

BACKGROUND: Dysfunctional osteogenesis of bone marrow mesenchymal stem cells (BMSCs) plays an important role in osteoporosis occurrence and development. However, the molecular mechanisms of osteogenic differentiation remain unclear. This study explored whether microfibrillar-associated protein 5 (MFAP5) regulated BMSCs osteogenic differentiation. METHODS: We used shRNA or cDNA to knock down or overexpress MFAP5 in C3H10 and MC3T3-E1 cells. AR-S- and ALP-staining were performed to quantify cellular osteogenic differentiation. The mRNA levels of the classical osteogenic differentiation biomarkers Runx2, Col1α1, and OCN were quantified by qRT-PCR. Finally, we employed Western blotting to measure the levels of Wnt/ß-catenin and AMPK signaling proteins. RESULTS: At days 0, 3, 7, and 14 after osteogenic induction, AR-S- and ALP-staining was lighter in MFAP5 knockdown compared to control cells, as were the levels of Runx2, Col1α1 and OCN. During osteogenesis, the levels of ß-catenin, p-GSK-3ß, AMPK, and p-AMPK were upregulated, while that of GSK-3ß was downregulated, indicating that Wnt/ß-catenin and AMPK signaling were activated. The relevant molecules were expressed at lower levels in the knockdown than control group; the opposite was seen for overexpressing cell lines. CONCLUSIONS: MFAP5 regulates osteogenesis via Wnt/ß­catenin- and AMPK-signaling; MFAP5 may serve as a therapeutic target in patients with osteoporosis.

KIAA1429 regulates cell proliferation by targeting c-Jun messenger RNA directly in gastric cancer.

N6-methyladenosine (m6A) modification regulatory proteins are involved in the development of many types of cancer. KIAA1429 serves as a scaffold in bridging the catalytic core components of the m6A methyltransferase complex. The role of KIAA1429 in gastric cancer and its related mechanism has not been reported upon. The expression of KIAA1429 was detected in human gastric cancer tissues and cell lines by quantitative real-time polymerase chain reaction and western blot. The effects of KIAA1429 on gastric cancer proliferation were evaluated by cell counting kit assays, colony formation assays, flow cytometry assay, and in vivo experiments with nude mice. And messenger RNA (mRNA) high-throughput sequencing, RNA immunoprecipitation assay (RIP), luciferase assay, and a rescue experiment were used to identify the relationship between KIAA1429 and its specific targeted gene, c-Jun. We found that KIAA1429 was upregulated in gastric cancer tissues, and expressed lower in adjacent tissues. The upregulated KIAA1429 promoted proliferation and downregulated KIAA1429 was proved to inhibit proliferation of gastric cancer in vitro and in vivo. Then, we identified the potential KIAA1429 regulating gene as c-Jun by mRNAs high-throughput sequencing and RIP assay. By luciferase assay, we verified that KIAA1429 regulated the expression of c-Jun in an m6A-independent manner. Finally, the overexpression of c-Jun rescued the inhibition of proliferation caused by KIAA1429 knockdown in gastric cancer cells. KIAA1429 could act as an oncogene in gastric cancer by stabilizing c-Jun mRNA in an m6A-independent manner. This highlights the functional role for KIAA1429 as a potential prognostic biomarker and therapeutic target in gastric cancer.

ATP-binding cassette g1 regulates osteogenesis via Wnt/ß-catenin and AMPK signaling pathways.

The dysfunction of bone marrow mesenchymal stem cells (BMSCs) in balancing osteogenesis and adipogenesis plays an important role in the occurrence and development of osteoporosis. It's still unknown that whether ATP-binding cassette g1 (Abcg1), a well-proved regulation gene of adipogenesis, regulates osteogenesis. In our previous study, we identified 30 differentially expressed genes in osteogenesis and found the expression level ofAbcg1 negatively related to osteogenesis among these genes. Abcg1 is a well-proven adipogenesis regulator and cholesterol transporter, but it's role in osteogenesis remained unknown. In this study we found it may control osteogenesis, further elucidating the exact role of Abcg1 in regulating osteoblast differentiation would help propose new strategies to prevent and treat osteoporosis. Therefore, we established Abcg1 up- or down-expressed C3H10T1/2 and C2C12 cell lines and verified that Abcg1 knockdown enhanced expression of osteogenic factors runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP), while Abcg1 overexpression reversed the promoting effect. Furthermore, we confirmed that Abcg1 modulated osteogenesis via the Wnt/ß-catenin and AMPK signaling pathways. taken together, these results suggest that Abcg1 may have an important role in regulating osteogenesis via Wnt/ß-catenin and AMPK signaling pathways, and expect to be a potential therapeutic target for osteoporosis.

DExH-Box helicase 58 enhances osteoblast differentiation of osteoblastic cells via Wnt/ß-Catenin signaling.

Discovering genes with regulatory effect of osteoblast differentiation and revealing mechanism of osteogenesis will enable us to find out more therapeutic methods for treating bone diseases. In this study, we supposed DHX58 may have a close relationship with osteogenesis and we then detected the expression of DHX58 during osteogenesis. We found that DHX58 was increased along with the osteogenic induction time extended. We then analyzed the function of DHX58 on ossification of mouse osteoblasts. The knockdown of DHX58 suppressed osteogenesis, as well as the expression of osteogenic biomarkers Runx2, OCN and Col1α1. Besides, the canonical Wnt/ß-Catenin signaling pathway was found significant inhibited as DHX58 downregulated, indicating it's the downstream pathway of DHX58 in regulating osteogenesis. Furthermore, we overexpressed DHX58 and the results were in accordance with the above findings. Taken together, our results indicated that DHX58 promotes osteogenesis of mouse osteoblasts via the canonical Wnt/ß-Catenin signaling pathway.

Hybrid Therapy Consisting of Bowel Resection and Fluoroscopic-Assisted Balloon Thrombectomy for Small Bowel Infarction Caused by Acute Mesenteric Venous Thrombosis.

BACKGROUND: To investigate the effect of bowel resection combined with fluoroscopic-assisted balloon thrombectomy for small bowel infarction caused by acute mesenteric venous thrombosis (AMVT). METHODS: Between June 2016 and August 2017, nine patients (seven males and two females; range, 40-73 years; mean, 55.11 ± 10.08 years) with small bowel infarction caused by AMVT underwent bowel resection combined with fluoroscopic-assisted balloon thrombectomy. The demographics, risk factors, therapeutic effect, complications, mortality, and follow-up of the study population were assessed. RESULTS: The effective rate was 100% with substantial clinical improvement in symptoms. All patients underwent small bowel resection with primary anastomosis. The length of bowel resection ranged from 60 to 170 cm (108.67 ± 35.05). In none of the cases there was surgery with second look. The patients were discharged 13-42 days (20.11 ± 8.75) after admission without perioperative complication or death. The follow-up period was 8-21 months (12.89 ± 4.65), and the follow-up rate was 100%. All patients returned to normal activities, regained lost body weight, and remained asymptomatic during the follow-up period. CONCLUSIONS: The combination therapy of bowel resection and fluoroscopic-assisted balloon thrombectomy is technically feasible and may be beneficial for small bowel infarction caused by AMVT in removing a thrombus efficiently, relieving symptoms rapidly, averting second-look surgery, lowering extensive surgical resections, and improving the prognosis.

Knocking down clock control gene CRY1 decreases adipogenesis via canonical Wnt/ß-catenin signaling pathway.

Cryptochrome gene 1(CRY1) is a member of circadian clock genes, which play an important role in adipocyte biology. CRY1 was reported to be related with the lipid metabolism, but the molecule mechanism of CRY1 in regulating the adipogenesis remains unclear. Here we report that CRY1 is a key regulator in adipogenic differentiation. We found that the expression levels of CRY1 in 3T3-L1 cells and C3H10T1/2 cells gradually increased during the process of adipogenic differentiation. Knockdown of endogenous CRY1 significantly inhibited the expression of adipogenic markers and lipid droplet formation in cells under adipogenic induction. In addition, knockdown of endogenous CRY1 promoted the expression and nuclear accumulation of ß-catenin, the critical signal molecular in the canonical canonical Wnt signaling pathway, suggesting the regulation effect of CRY1 in adipogenesis was mediated by canonical Wnt/ß-catenin signaling. Taken together, our study suggests that CRY1 regulates adipogenic differentiation through modulating the canonical Wnt/ß-catenin signaling pathway.

Photonic millimeter-wave ultrawideband signal generation using frequency upconversion based on the stimulated Brillouin scattering effect.

We present a novel and simple scheme for photonic generation of a millimeter-wave ultrawideband (UWB) signal free of low-frequency components that is implemented by using a stimulated Brillouin scattering (SBS)-based frequency-doubling method. A dual-parallel Mach-Zehnder modulator is incorporated to generate appropriate optical sidebands and an optical carrier carrying the UWB signal. Then the single-sideband modulation is realized based on the successive SBS frequency shifting process. Eventually, a UWB signal is upconverted to twice the frequency of the radio frequency signal. To vindicate the feasibility of the proposed scheme, an experiment is carried out, and it turns out that a UWB signal with a bandwidth of 7 GHz is upconverted to 21.75 GHz. The spectrum of the generated signal meets well with the Federal Communications Commission mask.

Preclinical Efficacy of Anti-RON Antibody-Drug Conjugate Zt/g4-MMAE for Targeted Therapy of Pancreatic Cancer Overexpressing RON Receptor Tyrosine Kinase.

Aberrant expression of the RON receptor tyrosine kinase, a cell surface protein, is a pathogenic feature in pancreatic cancer, which renders it a drug target for targeted therapy. Nevertheless, development of therapeutics targeting RON for pancreatic cancer therapy is hampered due to the lack of full addiction by pancreatic cancer cells to RON signaling for growth and survival. Here we describe a novel strategy using anti-RON antibody-directed drug delivery in the form of an antibody-drug conjugate for inhibition and/or eradication of pancreatic cancers. Monoclonal antibody Zt/g4 specific to the RON Sema domain was selected as the drug carrier based on its ability to induce robust RON internalization. Conjugation of Zt/g4 with monomethyl auristatin E, designated as Zt/g4-MMAE, was achieved through a protease-sensitive dipeptide linker to reach a drug to antibody ratio of 3.29:1. Zt/g4-MMAE was stable in human plasma with a dissociation rate less than 4% within a 10 day period. In vitro, Zt/g4-MMAE rapidly induced RON internalization, resulting in cell cycle arrest followed by massive cell death. The maximal effect was seen in pancreatic cancer cells with more than 10 000 receptor molecules per cell. Zt/g4-MMAE also synergized in vitro with chemotherapeutics including gemcitabine, 5-fluorouracil, and oxaliplatin to further reduce PDAC cell viability. In vivo, Zt/g4-MMAE exerts a long-lasting activity, which not only inhibited but also eradicated pancreatic xenograft tumors. These finding indicate that Zt/g4-directed drug delivery is highly effective for eradicating pancreatic tumors. Thus, Zt/g4-MMAE is a novel biotherapeutic with potential for therapy of RON-expressing pancreatic malignancies.

Cryptochrome 2 (CRY2) Suppresses Proliferation and Migration and Regulates Clock Gene Network in Osteosarcoma Cells.

BACKGROUND Circadian disruption is a potential cancer risk factor in humans. However, the role of the clock gene, cryptochrome 2 (CRY2), in osteosarcoma (OS) is still not clear. MATERIAL AND METHODS To evaluate the potential role of CRY2 in HOS osteosarcoma cells, CRY2-silenced cell lines were established. Furthermore, we investigated the effect of CRY2 knockdown on HOS cells by CCK-8, colony formation, migration assay, and flow cytometry, in vitro. RESULTS CRY2 knockdown promoted HOS OS cell proliferation and migration. We used a cell cycle assay to show that CRY2 knockdown increased the S phase cell population and reduced the G1 phase cell population. Western blot analyses showed that CRY2 knockdown decreased P53 expression and increased expression of c-myc and cyclin D1. Simultaneously, CRY2 knockdown increased the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, but did not change the phosphorylation of c-Jun N terminal kinase (JNK) and P38. CRY2 knockdown also increased the expression of matrix metalloproteinase (MMP)-2 and ß-catenin, and increased OS cell proliferation and migration by inducing cell cycle progression and promoting mitogen-activated protein kinase (MAPK) and Wnt/ß-catenin signaling pathways. Although it has previously been unclear whether the expression of CRY2 affects the expression of other clock genes in the clock gene network, our results show that knockdown of CRY2 significantly increased the mRNA expression of CRY1, Period (PER) 1, PER2, BMAL1, and CLOCK. CONCLUSIONS Our results suggest that CRY2 may be an anti-oncogene in OS, whose functions involve both downstream genes and other circadian genes.

Variation of sentinel lymphatic channels (SLCs) and sentinel lymph nodes (SLNs) assessed by contrast-enhanced ultrasound (CEUS) in breast cancer patients.

BACKGROUND: The objective of this study was to assess the feasibility of detecting the variation of sentinel lymphatic channels (SLCs) and sentinel lymph nodes (SLNs) in breast cancer patients using contrast-enhanced ultrasound (CEUS). METHODS: A total of 46 breast cancer patients were prospectively recruited in the study. All the participants received intradermal and peritumoral injection of microbubbles as contrast agent, and SLCs and SLNs were assessed preoperatively. Blue dye was injected subareolarly and peritumorally during the surgery. The SLNs detected by CEUS and blue dye were sent to the pathology laboratory for histopathological analysis. RESULTS: At least one SLC and SLN were detected by CEUS in all 46 cases. Three types of SLCs were detected, including superficial sentinel lymphatic channels (SSLCs), penetrating sentinel lymphatic channels (PSLCs), and deep sentinel lymphatic channels (DSLCs). Five lymphatic drainage patterns (LDPs) were found, including SSLC, PSLC, SSLC + PSLC, SSLC + DSLC, and SSLC + PSLC + DSLC. Only SSLC was detected on CEUS in 24 cases; only PSLC was detected in 3 cases; both SSLC and PSLC were detected in 8 cases; both SSLC and DSLC were detected in 7 cases; SSLC, PSLC, and DSLC were all detected in the remaining 4 cases. An actual LDP was defined on the combination of CEUS and dissection of the specimen. The accuracy rate of CEUS was 43/46. Interestingly, a bifurcated SLC was found in 8 patients. In 3 patients, a discontinuous SLC and non-enhanced SLN were found by CEUS. Also, no dyed SLNs were detected during the surgery. The axillary lymph nodes turned out tumor involved histologically. CONCLUSION: CEUS is feasible to assess the variation of SLCs and SLNs preoperatively in breast cancer patients. SLNB is not suggested when a discontinuous SLC and non-enhanced SLN were detected by CEUS.

The effects of triptolide on the pharmacokinetics of sorafenib in rats and its potential mechanism.

CONTEXT: Combining sorafenib with triptolide could inhibit tumour growth with greater efficacy than single-agent treatment. However, their herb-drug interaction remains unknown. OBJECTIVE: This study investigates the herb-drug interaction between triptolide and sorafenib. MATERIALS AND METHODS: The effects of triptolide (10 mg/kg) on the pharmacokinetics of different doses of sorafenib (20, 50 and 100 mg/kg) in rats, and blood samples were collected within 48 h and evaluated using LC-MS/MS. The effects of triptolide on the absorption and metabolism of sorafenib were also investigated using Caco-2 cell monolayer model and rat liver microsome incubation systems. RESULTS: The results showed that the Cmax (low dose: 72.38 ± 8.76 versus 49.15 ± 5.46 ng/mL; medium dose: 178.65 ± 21.05 versus 109.31 ± 14.17 ng/mL; high dose: 332.81 ± 29.38 versus 230.86 ± 9.68 ng/mL) of sorafenib at different doses increased significantly with the pretreatment of triptolide, and while the oral clearance rate of sorafenib decreased. The t1/2 of sorafenib increased significant (p < 0.05) from 9.02 ± 1.16 to 12.17 ± 2.95 h at low dose with the pretreatment of triptolide. Triptolide has little effect on the absorption of sorafenib in Caco-2 cell transwell model. However, triptolide could significantly decrease the intrinsic clearance rate of sorafenib from 51.7 ± 6.37 to 32.4 ± 4.43 µL/min/mg protein in rat liver microsomes. DISCUSSION AND CONCLUSIONS: These results indicated that triptolide could change the pharmacokinetic profiles of sorafenib in rats; these effects might be exerted via decreasing the intrinsic clearance rate of sorafenib in rat liver.

miR-124-3p functions as a tumor suppressor in breast cancer by targeting CBL.

BACKGROUND: The origin and development of breast cancer remain complex and obscure. Recently, microRNA (miRNA) has been identified as an important regulator of the initiation and progression of breast cancer, and some studies have shown the essential role of miR-124-3p as a tumor suppressor in breast tumorigenesis. However, the detailed role of miR-124-3p in breast cancer remains poorly understood. METHODS: Quantitative RT-PCR and western blotting assays were used to measure miR-124-3p and CBL expression levels in breast cancer tissues, respectively. Luciferase reporter assay was employed to validate the direct targeting of CBL by miR-124-3p. Cell proliferation and invasion assays were performed to analyze the biological functions of miR-124-3p and CBL in breast cancer cells. RESULTS: In the present study, we found that miR-124-3p was consistently downregulated in breast cancer tissues. Moreover, we showed that miR-124-3p significantly suppressed the proliferation and invasion of breast cancer cells. In addition, we investigated the molecular mechanism through which miR-124-3p contributes to breast cancer tumorigenesis and identified CBL (Cbl proto-oncogene, E3 ubiquitin protein ligase) as a direct target gene of miR-124-3p. Moreover, we found that ectopic expression of CBL can attenuate the inhibitory effect of miR-124-3p on cell proliferation and invasion in breast cancer cells. CONCLUSIONS: This study identified a new regulatory axis in which miR-124-3p and CBL regulate the proliferation and invasion of breast cancer cells.

Ribosomal proteins and human diseases: pathogenesis, molecular mechanisms, and therapeutic implications.

Ribosomes are essential components of the protein synthesis machinery. The process of ribosome biogenesis is well organized and tightly regulated. Recent studies have shown that ribosomal proteins (RPs) have extraribosomal functions that are involved in cell proliferation, differentiation, apoptosis, DNA repair, and other cellular processes. The dysfunction of RPs has been linked to the development and progression of hematological, metabolic, and cardiovascular diseases and cancer. Perturbation of ribosome biogenesis results in ribosomal stress, which triggers activation of the p53 signaling pathway through RPs-MDM2 interactions, resulting in p53-dependent cell cycle arrest and apoptosis. RPs also regulate cellular functions through p53-independent mechanisms. We herein review the recent advances in several forefronts of RP research, including the understanding of their biological features and roles in regulating cellular functions, maintaining cell homeostasis, and their involvement in the pathogenesis of human diseases. We also highlight the translational potential of this research for the identification of molecular biomarkers, and in the discovery and development of novel treatments for human diseases.

Identification of a new class of MDM2 inhibitor that inhibits growth of orthotopic pancreatic tumors in mice.

BACKGROUND & AIMS: The oncogene MDM2, which encodes an E3 ubiquitin ligase, is overexpressed in pancreatic cancers and is therefore a therapeutic target. Current inhibitors of MDM2 target the interaction between MDM2 and P53; these would have no effect on cancer cells that do not express full-length P53, including many pancreatic cancer cells. We searched for a compound that specifically inhibits MDM2 itself. METHODS: We performed a virtual screen and structure-based design to identify specific inhibitors of MDM2. We tested the activities of compounds identified on viability, proliferation, and protein levels of HPAC, Panc-1, AsPC-1, and Mia-Paca-2 pancreatic cancer cell lines. We tested whether intraperitoneal injections of one of the compounds identified affected growth of xenograft tumors from Panc-1 cells, or orthotopic tumors from Panc-1 and AsPC-1 cells (injected into pancreata), in nude mice. RESULTS: We identified a compound, called SP141, which bound directly to MDM2, promoting its auto-ubiquitination and degradation by the proteasome. The compound reduced levels of MDM2 in pancreatic cancer cell lines, as well as their proliferation, with 50% inhibitory concentrations <0.5 µM (0.38-0.50 µM). Increasing concentrations of SP141 induced increasing levels of apoptosis and G2-M-phase arrest of pancreatic cancer cell lines, whether or not they expressed functional P53. Injection of nude mice with SP141 (40 mg/kg/d) inhibited growth of xenograft tumors (by 75% compared with control mice), and led to regression of orthotopic tumors. CONCLUSIONS: In a screen for specific inhibitors of MDM2, we identified a compound called SP141 that reduces levels of MDM2 in pancreatic cancer cell lines, as well as their proliferation and ability to form tumors in nude mice. SP141 is a new class of MDM2 inhibitor that promotes MDM2 auto-ubiquitination and degradation. It might be further developed as a therapeutic agent for pancreatic cancer.